United States
Environmental Protection
Agency
United States
Corps of Engineers
Environment
Canada
Environmental Research
Laboratory
Corvallis OR 97330
EPA-600/8-79-027
September 1 979
Research and Development
Cold Climate
Utilities  Delivery

Design Manual

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                            ACKNOWLEDGEMENTS


          The creation of this Cold Climate Utilities Delivery Design

Manual took place through the efforts of an eight-member Steering

Committee.  The individual members of this Committee represent eight
different groups involved in either design, research or academic efforts

in the North.  These groups are based in both Canada and the United
States.  The time, material and support of these groups is greatly

acknowledged.

                  James J. Cameron
                  Northern Technology Unit
                  Environmental Protection Service
                  Environment Canada
                  Rm. 804, 9942-108th Street
                  Edmonton, Alberta  T5K 2J5

                  Gary W. Heinke
                  Department of Civil Engineering
                  University of Toronto
                  Toronto, Ontario  M5S 1A4

                  Fred James
                  Department of Public Works
                  Government of the Northwest Territories
                  Yellowknife, Northwest Territories  XOE  1HO

                  Sherwood C. Reed, Co-chairman
                  U.S. Army Cold Regions Research and
                    Engineering Laboratory
                  Box 282
                  Hanover, New Hampshire  03755

                  Barry Reid
                  U.S. Environmental Protection Agency
                  Corvallis Environmental Research Laboratory
                  200 S.W. 35th Street
                  Corvallis, Oregon  97330

                  William L. Ryan
                  U.S. Public Health Service
                  Navajo Area, Indian health Service
                  P.O. Box G
                  Window Rock, Arizona  96515

                  Jonathan W. Seribner
                  Alaska Department of Environmental Conservation
                  Pouch 0
                  Juneau, Alaska  99811

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                  Daniel W. Smith, Chairman
                  University of Alberta
                  Department of Civil Engineering
                  Edmonton, Alberta  T6G 2G7
          Dr. Haldor Aamot of USA CREEL was responsible  for  preparation
of the section on Energy Management.  In addition, the U.S.  Army  Corps
of Engineers District in Anchorage, Ak, contributed  to Sections  10  and
14.  The assistance provided by R&M Consultants, Inc. is acknowledged
and appreciated.
          The technical review and suggestions contributed by  R. S.
Sletten and P. Given ^^ ,*,. are acknowledged.  The editorial  review
provided by Ms. V. Jones, Head, Publications Section (Water),
Environmental Protection Service, Environment Canada, is gratefully
acknowledged by the Steering Committee.

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                                         COLD CLIMATE UTILITIES

                                         DELIVERY DESIGN MANUAL
                                               prepared by
                                             a  committee of
                Daniel  W.  Smith,  Chairman
                University of  Alberta
                Sherwood  Reed,  Co-chairman
                U.S.  Army Cold  Regions Research
                and  Engineering Laboratory

                James J.  Cameron
                Environment  Canada

                Gary W. Heinke
                University of Toronto
Fred James
Government of the
Northwest Territories
Barry Reid
U.S. Environmental
Agency
Protection
William L. Ryan
U.S. Public Health Service

Jon Scribner
Alaska Department of
Environment Conservation
                                         Report  No.  EPS  3-WP-79-2
                                              March 1979
V

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                                DISCLAIMER

This  report has been reviewed by  the  Corvallis Environmental Research
Laboratory, U.S. Environmental Protection Agency,  and approved for
publication. Mention of trade names or commercial  products does not
constitute endorsement or recommendation for use.
 Minister of Supply and Services Canada 1979



 Cat. No. En43-3/79-2

 ISBN 0-662-10349-1



 N de Central En43-3/79-2

 ISBN 0-662-10349-1
Reproduced  by permission of  the
Minister of Supply and Services Canada

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                                FOREWORD

         The concept  for  this manual  emerged  at  the  symposium on
'Utilities Delivery in Arctic Regions' organized  by  Environment Canada in
Edmonton, March 16-18, 1976.  The  several  U.S. and Canadian  agencies
responsible for environmental improvement  in  the  north  were  requested to
assemble a team of experts which would pool  its  knowledge to create a
'state-of-the-art' design manual on planning  and  servicing northern
communities.  In  the  ensuing months efforts  in both  countries resulted in
the creation of a steering committee, and  the commitment  of  staff and
funding to allow  this undertaking.  Meetings  of  the  committee took place
in Anchorage, Seattle, Yellowknife, and Edmonton.  Each member of the
committee was assigned lead responsibility for one or more sections.
         The purpose  of the manual is to provide  guidance and criteria
for the design of utility systems  in  cold  regions to an engineer
experienced in southern municipal  engineering practice.  He  or she may be
working for government, consulting engineers  or  industry, and would be
involved in the planning, design,  construction or operation  of utility
services in a northern community or industrial establishment.  It is
hoped that this manual will help to improve  the  level of  services provided
and to avoid many of  the  mistakes  made in  the past by transferring
'southern engineering' to the North without  proper modifications.  Often,
a new approach utilizing  basic environmental  engineering  principles
suitable to the north is  required.
         It is recognized that errors and  omissions may have occurred
during the preparation of this manual.  The  authors would apppreciate
comments and supplemental information which  could be incorporated into
revisions of the manual.  It is the belief of the authors that this
manual must be updated periodically.  Comments and recommendations should
be sent to the:
                    Northern Technology Unit
                    Environmental  Protection  Service
                    Environment Canada
                    8th Floor
                    9942-108 St.
                    Edmonton, Alberta T5K  2J5

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                                  ii
                              AVANT-PROPOS

         Ce manuel a ete concu a la suite du colloque sur la
"Distribution et 1'Evacuation des eaux dans les regions arctiques",
organise a Edmonton par Environnement Canada les 16, 17 et 18 mars 1976.
On avait invite, lors de cette reunion, les organismes canadiens et
americains responsables de 1'amelioration de 1'environnement dans le
Nord, a former une equipe de specialistes.  Ceux-ci devaient mettre leurs
connaissances en commun en vue de creer un manuel de conception a jour,
destine a planifier 1'installation des localites nordiques et les services
essentiels dont elles ont besoin.  Par la suite, les deux pays se sont
concertes pour creer un comite directeur et ont affecte les fonds et le
personnel necessaires au bon fonctionnement de 1'entreprise.  Le comite
s'est reuni a Anchorage, Seattle, Yellowknife et Edmonton.  Chaque membre
s'est vu confier la responsabilite d'une ou de plusieurs sections.
         Le manuel se propose de fournir, aux ingenieurs formes aux
techniques courantes dans les municipalites du Sud, des conseils et des
criteres applicables a la conception de reseaux de  services pour les
regions du Nord.   Ces ingenieurs peuvent etre au service du gouvernement,
d'une firme d'ingenieurs conseil ou d'une Industrie et participer a la
planification, a la conception, a la construction ou a 1'exploitation du
reseau de services d'une localite ou d'une Industrie situees dans le
Nord.  II est a esperer que ce manuel aidera  ameliorer la qualite des
services et a eviter les erreurs commises dans le passe ou les pratiques
de technogenie applicables aux communautes du Sud etaient raises en
oeuvre, sans modifications prealables, dans les localites du Nord.  La
nouvelle facon d'aborder ces questions repose sur les principes
fondamentaux de technogenie environnementale adaptes aux regions
nordiques.
         Certaines erreurs ont pu se glisser dans ce manuel lors de sa
preparation.  Les  auteurs vous sauraient gre de leur faire parvenir vos
commentaires ou des renseignements qui pourraient s'ajouter au texte lors
des  revisions periodiques.  L'adresse est la suivante:
                    Sous-section de la technologie  nordique
                    Service de la protection de 1'environnement
                    Environment Canada
                    8e etage
                    9942-1086 rue
                    Edmonton (Alberta)  T5K  2J5

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                                  iii
                           TABLE OF CONTENTS
                                                                    Page
FOREWORD                                                              i
TABLE OF CONTENTS                                                    iii

1        INTRODUCTION                                                1-1
1.1      Water Supply                                                1-2
1.2      Water Distribution and Sewage Collection                    1-3
1.3      Waste Disposal                                              1-4
1.4      Solid Waste Management                                      1-5
1.5      Fire Protection                                             1-5
1.6      Energy Management                                           1-6
1.7      Summary and Future Needs                                    1-6

2        PLANNING AND PRELIMINARY CONSIDERATIONS                     2-1
2.1      Objectives                                                  2-1
2.2      Regulations and Legislation                                 2-6
2.3      Type of Installation or Site                                2-9
2.4      Site Considerations                                         2-9
2.5      Project Management                                          2-33
2.6      Water Delivery and Waste Collection Systems                 2-47
2.7      Operation and Maintenance                                   2-53
2.8      References                                                  2-57
2.9      Bibliography                                                2-59

3        WATER SOURCE DEVELOPMENT                                    3-1
3.1      General                                                     3-1
3.2      Water Sources                                               3-3
3.3      Water Requirements                                          3-10
3.4      Structures                                                  3-18
3.5      References                                                  3-31
3.6      Bibliography                                                3-32

4        WATER TREATMENT                                             4-1
4.1      General                                                     4-1

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                                   iv
                        TABLE OF CONTENTS (CONT')
                                                                    Page
4.2      Process Design                                             4-1
4.3      Plant Design                                               4-14
4.4      References                                                 4-17
4.5      Bibliography                                               4-17

5        WATER STORAGE                                              5-1
5.1      Purposes and Capacity Requirements                         5-1
5.2      Tanks                                                      5-2
5.3      Earth Reservoirs                                           5-12
5.4      References                                                 5-18
5.5      Bibliography                                               5-19

6        WATER DISTRIBUTION                                         6-1
6.1      Introduction                                               6-1
6.2      General Assumptions and Design Considerations              6-1
6.3      Self-haul Systems                                          6-3
6.4      Community-wide Haul System                                 6-5
6.5      Piped Systems                                              6-17
6.6      Service Lines                                              6-28
6.7      Materials of Construction                                  6-35
6.8      Appurtenances                                              6-40
6.9      Back-up Freeze Protection Mechanisms                       6-47
6.10     References                                                 6-49
6,11     Bibliography                                               6-50

7        WASTEWATER COLLECTION                                      7-1
7.1      Sources of Wastewater                                      7-1
7.2      Individual Bucket Systems                                  7-4
7.3      Vehicle-haul With House Storage Tanks                      7-7
7.4      Piped Collection Systems                                   7-13
7.5      Lift Stations                                              7-31
7.6      Building Plumbing                                          7-34
7.7      Typical Construction Costs                                 7-37

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                     TABLE OF CONTENTS (cont'd)
                                                                    Page
7.8      References                                                 7-41
7.9      Bibliography                                               7-44

8        UTILIDORS                                                  8-1
8.1      Definition and Overview                                    8-1
8.2      Design                                                     8-4
8.3      Components and Materials                                   8-11
8.4      Appurtenances                                              8-15
8.5      Thermal Considerations                                     8-18
8.6      Maintenance                                                8-19
8.7      Costs                                                      8-20
8.8      References                                                 8-21

9        WASTEWATER TREATMENT                                       9-1
9.1      General Considerations                                     9-1
9.2      Wastewater Characteristics                                 9-2
9.3      Unit Operations                                            9-8
9.4      Unit Processes                                             9-11
9.5      On-site Treatment                                          9-32
9.6      Operation and Maintenance                                  9-34
9.7      Costs                                                      9-36
9.8      References                                                 9-39
9.9      Bibliography

10       WASTEWATER DISPOSAL                                        10-1
10.1     Discharge Standards                                        10-1
10.2     Subsurface Land Disposal                                   10-4
10.3     Outfalls                                                    '0-9
10.4     Intermittent Discharge                                     '0-12
10.5     Land Disposal                                              10-15
10.6     Swamp Discharge                                            10-16
10.7     Sludge Disposal                                            10-18
10.8     References                                                 10-20

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                                  vi
                     TABLE OF CONTENTS (cont'd)
                                                                    Page
11       CENTRAL FACILITIES AND REMOTE CAMPS                        11-1
11.1     Introduction                                               11-1
11.2     Central Facilities                                         11-2
11.3     Remote Camps                                               11-30
11.4     References                                                 11-34

12       FIRE PROTECTION                                            12-1
12.1     General                                                    12-1
12.2     Administration of Fire Prevention Standards                12-1
12.3     Codes and Guidelines                                       12-2
12.4     Fire Prevention Criteria                                   12-2
12.5     Equipment                                                  12-3
12.6     Community Fire Alarm Systems                               12-8

13       SOLID WASTE MANAGEMENT                                     13-1
13.1     General                                                    13-1
13.2     Municipal Solid Wastes                                     13-2
13.3     Industrial and Special Wastes                              13-20
13.4     Human Wastes From Households and Establishments            13-21
13.5     References                                                 13-32

14       ENERGY MANAGEMENT                                          14-1
14.1     Basic Considerations                                       14-1
14.2     Energy Supply                                              14-5
14.3     Energy Distribution                                        14-21
14.4     References                                                 14-43

15       THERMAL CONSIDERATIONS                                     15-1
15.1     Introduction                                               15-1
15.2     Freezing  of Pipes                                          15-2
15.3     Heat Loss From Pipes                                       15-7
15.4     Heat Loss Replacement                                      15-15

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                                  vii
                       TABLE OF CONTENTS (cont'd)
                                                                    Page
15.5     Utility Systems                                            15-21
15.6     Foundations for Pipelines                                  15-23
15.7     Materials                                                  15-28
15.8     Buildings and Structures                                   15-36
15.9     Thermal Calculations                                       15-38
15.10    Example Problems                                           15-58
15.11    References                                                 15-72
ACKNOWLEDGEMENTS
SYMBOLS AND ABBREVIATIONS
GLOSSARY
APPENDIX A - PIPE MATERIALS
APPENDIX B - WATER CONSERVATION ALTERNATIVES
APPENDIX C - THERMAL PROPERTIES
APPENDIX D - TRUCKED SYSTEMS
APPENDIX E - VEHICLE SPECIFICATIONS
APPENDIX F - THAWING FROZEN PIPELINES
APPENDIX G - FIRE PROTECTION STANDARDS
APPENDIX H - ENERGY MANAGEMENT DATA

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                                SECTION 1
                              INTRODUCTION
                                  Index
                                                                    Paee
1        INTRODUCTION                                               1-1
1.1      Water Supply                                               1-2
1.2      Water Distribution and Sewage Collection                   1-3
1.3      Waste Disposal                                             1-4
1.4      Solid Waste Management                                     1-5
1.5      Fire Protection                                            1-5
1.6      Energy Management                                          1-6
1.7      Summary and Future Needs                                   1-6

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                                  1-1
1        INTRODUCTION
         "Cold climate" in this manual means the climate experienced in
the arctic and subarctic regions of the United States and Canada.*  They
include Alaska, the Yukon and Northwest Territories, northern  parts of
some of the Canadian provinces and some high altitude areas of  the
northern contiguous United States.  The special problems of providing
utility services in these regions are addressed in this manual, which may
also be helpful for other cold climate regions, such as the Antarctic,
Greenland, Scandinavia and the U.S.S.R.
         A vast, frozen land inhabited by but a few people; that  is the
impression most "southerners' have of Alaska, the Yukon and the Northwest
Territories.  Much of the evidence supports this impression.   About
500,000 people live in Alaska, about 30,000 in the Yukon Territory and
about 45,000 in the Northwest Territories.  Disregarding national
boundaries, this vast land stretches over 5,000 kilometres, from  Davis
Strait in the east to the Bering Sea in the west.  It extends  2,500
kilometres from the northern parts of the Canadian provinces to
uninhabited lands near the North Pole.  The recent interest in  the energy
and material reserves of the North have made people more aware  of these
regions and of the modern communities of sizeable population,  such as
Anchorage (200,000), Fairbanks (45,000) and Barrow (3,000) in  Alaska, and
Whitehorse (16,000) in the Yukon Territory, and Yellowknife (12,000) and
Frobisher Bay (2,500) in the N.W.T., to name some of the larger ones.  In
total there are about 250 communities with populations between  10(J and
1,000 people.  Most settlements were established long before the
provision of municipal services was considered important.  Their  location
and haphazard layout were based on survival and personal preferences.
This has now resulted in high cost for services, which in turn  delays the
extension of modern community services to these settlements.
         Several factors cause special problems to the development of
services in northern communities.  Among them are:  permafrost, climate,
remoteness, lack of planning for services, inadequate housing,  and often
lack of an economic base.  The degree of influence of these factors
* Terms throughout this manual are defined in the glossary.

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                                   1-2
varies considerably over  this  huge  land.   Permafrost occurs where the
mean annual ground temperatures  are  below  0C  for several years.  Its
thickness varies with location and  can  be  up  to  600  metres.  Climatic
variations are great.  Minimum and  maximum temperatures may average as
low as -50C and as high  as  30C.   Mean annual  total precipitation
(rain and snow) varies from  about 15  to 45 cm,  quite low compared to
southern areas.
         The remoteness of most  communities results  in high transporta-
tion costs.  Most of the  materials  used for services must be imported.
The spread-out, low density  layout  of existing  settlements results in
further high costs.  Replanning  of  a  settlement,  including relocation of
roads and houses, is, or  should  be,  a prerequisite  to construction of
piped water and sewer systems.   In  some cases,  complete relocation of a
settlement may be the most economical solution  for  servicing the community.
Upgrading existing housing and construction of  low  and high density
housing for permanent and transient  populations  are  required.   Central
commercial, educational and  recreational facilities  must be incorporated
in the community plan.  Any  useful  and  practical  plan, be it for housing,
schooling or servicing, must be  both  technically  and economically sound,
and most important, socially acceptable to all  groups of the community,
both natives and newcomers.
1.1      Water Supply
         All traditional  sources of water  are  present in most  parts of
the cold regions but conditions  peculiar to these regions require special
consideration of these sources prior  to selection of a community water
supply.  For example, although there  are many  lakes, they are  generally
quite shallow and many freeze  to the  bottom, or  their effective storage
capacity is severely reduced by  thick ice  that  forms each winter.  This
also tends to concentrate minerals  in the  unfrozen water, which may
render it unsuitable for  consumption.   Surface  water is often  highly
coloured from the organic material washed  into  lakes by runoff.  Because
of low precipitation, water  contained in lakes  may be the result of many
years'  accumulation.  Attempts to utilize  large amounts of this water may
drain the lake and cause  loss  of supply.   During  the winter, clean water

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                                      1-3
 can be obtained from beneath the ice of rivers, but during breakup,
 floating  ice and other debris carried by the flood waters are a hazard to
 any permanent  installation, such as a water intake.  Following breakup,
 the silt  content of the river is extremely high, possibly rendering the
 water unusable for several weeks.  Small rivers and creeks often freeze
 to the bottom, and so their use as a water source may be limited to cer-
 tain times of  the year.  They may also be polluted from waste discharges.
 Reservoirs are difficult to construct where the underlying soil has a
 high ice  content; any attempt to pond water will cause melting of the
 underlying permafrost and possible settlement of the dykes.
     Groundwater is an excellent source of supply in remote northern
 locations.  However, in continuous and discontinuous permafrost regions a
 reliable  groundwater source normally must be obtained from beneath the
 frozen zone.  This often means expensive wells due to thermal protection
 requirements.  In addition, the well water may be highly mineralized.  In
 some locations, ice and snow are melted for water, but the high cost of
 fuel or electricity makes this source of water uneconomical if adequate
 quantities are to be provided.  Water consumption rates show large
 variation depending on the method of distribution and the plumbing
 facilities.  A water supply objective of 50 litres per person per day is
 generally considered minimum for adequate drinking, cooking, bathing and
 laundering purposes.  Only piped systems or a well-equipped trucked
 water system can meet this objective.   In many communities, houses without
 plumbing that are currently served by a trucked water system, only 10 litres
 per person per day is supplied and used.

 1.2  Water Distribution and Sewage Collection
     The dominant characteristic of cold regions utility systems is
 the need to prevent both the water and sewage lines from freezing.   Heat
 may be added to the water or to the mains,  and continuous circulation
 maintained to prevent freezing.   The degree of freeze protection required
 depends on whether the pipes are buried or  built above ground.   Buried
water and sewer lines are preferred for community planning, aesthetic and
 engineering reasons.   In areas with subarctic climate (arbitrarily
defined as one in which one to three calendar months  have mean monthly
temperatures above 10C),  such as Anchorage,  Fairbanks,  Whitehorse  and

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                                      1-4
Yellowknife, underground systems are used.   They differ from southern
systems in that various methods of freeze protection are provided,  such
as insulation, heating, recirculation and water wasting.  Insulation
around pipes also prevents thawing of ice-rich permafrost and consequent
settling of pipes.  In the past, underground services were considered to
be not feasible, technically and economically, in ice-rich permafrost
areas.  Therefore, above-ground utility systems were constructed in such
areas.  They are generally more expensive,  cause difficulties with roads
and drainage, are subject to vandalism, and are not desirable from
community planning and aesthetic points of view.  Recent engineering
developments may allow underground construction in areas where this was
thought not possible in the past.  This will reduce future use of above-
ground utilidors.  However, above-ground utility systems will still be
necessary in thermally-sensitive, ice-rich, permafrost areas, or where
excavation equipment is not available for installation and maintenance
or for temporary facilities.
     Trucked delivery of water and pickup of sewage is an alternate
means of providing services.  Water storage tanks used for homes vary from
an open reused oil drum (180 L) to proper tanks of 1200-litre or more
capacity.  In some settlements, water is delivered only to some homes.
Others must pick up water in pails from a number of water points within
the settlement.  When the house is equipped with complete indoor plumb-
ing, all wastes are generally discharged to a holding tank, which must
be pumped out several times per week.  When indoor plumbing is not avail-
able, toilet facilities may consist of pit privies or chemical toilets
of various designs; however, they usually consist of "honey bags", plas-
tic bags in a container under the toilet.  "Honey bags" are picked up
daily or several times per week on a community-wide basis.  Wash water
wastes, kitchen sink wastes, and laundry water are usually disposed of
to the ground surface in the immediate vicinity of the home, often contri-
buting to localized drainage and health problems.

1.3       Waste Disposal
          Very few communities have sewage treatment plants, although
there are now many package-type plants at industrial facilities in Alaska
which were built as a consequence of the oil discovery and pipeline

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                                  1-5
construction.  Sewage lagoons are the most common method  for  the  treat-
ment of wastewater.  Few of these meet recommended design and  operating
criteria.  In the past, they were often constructed by utilizing  existing
lakes or low areas with suitable addition of dykes.  For  most  of  the year
they provide long-term storage of wastewater, with some anaerobic  decom-
position taking place.  It is during the summer that extensive biological
activity occurs, with resulting reduction in organic matter.   The  rela-
tively lower effectiveness of lagoons for wastewater treatment is  offset
by their lack of need for skilled and costly operation and maintenance.
In certain subarctic locations, septic tanks and tile fields  are  used. In
communities near the ocean, disposal of wastewater is often to the  sea.
This practice may not be permitted without a special study of  local
conditions or some degree of treatment in the future.
1.4      Solid Waste Management
         Human feces in "honey bags" are often disposed of without  any
treatment in a dump, together with solid waste.  In some  cases, pits have
been constructed.  In other cases, the contents are emptied into  a  lagoon
which also receives wastewater.  Solid waste disposal has, until  recent
years, been the most neglected area of sanitation.  Where a community
collection system exists, disposal is generally at a dump.  Because of
lack of proper cover material, sanitary landfill cannot be practised in
most places.  Few dumps are fenced, contributing to widespread and
uncontrolled dumping.  In some cases, ill-chosen dump sites contribute to
water pollution.  Other forms of refuse disposal, such as incineration,
shredding, baling, etc., have found limited application due to high
maintenance and operational costs.
1.5      Fire Protection
         One of the most serious hazards to life and property  in  remote
northern locations is fire.  The seriousness of fire is aggravated  by the
problems of providing adequate quantities of water to fight fires  during
the extremely cold periods of the year, the extreme dryness of wood and
organic materials, and the dependence on heating systems  for  survival.
Fire protection techniques must be approached at all levels:   the use of
fire retardant materials, development and use of early warning devices,

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                                  1-6
the provision of fire control equipment and personnel, and educational
efforts towards fire prevention.
1.6      Energy Management
         Conservation of energy becomes especially important in cold
climate areas.  The costs of heating buildings, lighting, hot water, and
operation of appliances are generally much higher than in southern areas.
Heating expenses can be reduced by heavy insulation of buildings and
increased use of waste heat from generating stations.  Oil, gas, coal,
wood and hydro-generated electricity are now most commonly used as energy
sources.  These may be supplemented by geothermal, solar, and wind energy
where and when feasible.
1.7      Summary and Future Needs
         An evaluation of the present level of sanitation in most of the
smaller northern communities shows that the overall situation is more
primitive than in comparably-sized southern communities, but that the
situation is steadily improving.  Goals have been set out broadly, for
instance, in the "Proposed Water and Sanitation Policy for Communities in
the N.W.T., 1973".  Implementation of these goals will, to a large
extent, depend on available funds.
         Development of the northern areas of Canada and of Alaska will
undoubtedly increase in the next few decades, but the scale and pace of
development is still somewhat uncertain.  Resource development, including
oil, natural gas, mining, hydro-electric works and transportation
facilities, such as pipelines, roads, railroads, bridges, harbours and
airports, will be built.  Several different types of communities will
have to be developed, such as construction and permanent camps, the
expansion and improvement of existing communities, and the building of
new towns.  The engineering community must be ready to plan, design,
construct and operate facilities appropriate for the conditions
encountered.

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                                SECTION 2
                 PLANNING AND PRELIMINARY CONSIDERATIONS
                                  Index
                                                                    Page
2        PLANNING AND PRELIMINARY CONSIDERATIONS                    2-1
2.1      Objectives                                                 2-1
2.1.1    Health                                                     2-1
2.1.2    Social/economic                                            2-4
2.2      Regulations and legislation                                2-6
2.2.1    Water rights                                               2-6
2.2.2    Waste discharge permits                                    2-6
2.2.3    Archaeological clearances                                  2-7
2.2.4    Environmental assessments or impact statements             2-7
2.2.5    Rights-of-way and easements                                2-7
2.2.6    Land use permits                                           2-8
2.2.7    Safety standards during construction                       2-8
2.2.8    Structures in navigable waters                             2-8
2.2.9    Safe drinking water regulations                            2-8
2.2.10   Clearing houses                                            2-9
2.3      Type of Installation or Site                               2-9
2.4      Site Considerations                                        2-9
2.4.1    Permafrost                                                 2-9
2.4.2    Location                                                   2-12
2.4.3    Layout                                                     2-20
2.4.4    Energy                                                     2-25
2.4.5    Utilities                                                  2-25
2.4.6    Building design                                            2-28
2.4.7    Revegetation                                               2-32
2.5      Project Management                                         2-33
2.5.1    Construction season                                        2-33
2.5.2    Transportation                                             2-36
2.5.3    Equipment                                                  2-42
2.5.4    Labour and inspection                                      2-43
2.5.5    Type of construction                                       2-44

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                             Index (Cont'd)
                                                                    Page
2.6      Water Delivery and Waste Collection Systems                2-47
2.6.1    Types of systems including construction, operation and
         maintenance costs                                          2-47
2.6.2    Design life                                                2-52
2.7      Operation and Maintenance                                  2-53
2.7.1    Community and operator training                            2-53
2.7.2    Operation and maintenance manuals                          2-55
2.7.3    Reliability                                                2-56
2.7.4    Management backup                                          2-56
2.8      References                                                 2-57
2.9      Bibliography                                               2-59

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                                List of Figures
                                                                      Page
          Unalakleet,  Alaska                                          2-2
2-2       Ice Stacked  to be Melted for Drinking  Water
          Kotzebue,  Alaska                                            2-2
2-3       "Beaded" Stream                                             2-10
2-4       Frost Polygon on Alaska's North Slope                        2-11
2-5       Ice Wedge                                                   2-11
2-6       Areal Distribution of Permafrost in the Northern
          Hemisphere                                                  2-13
2-7       Permafrost in Alaska                                        2-14
2-8       Distribution of Permafrost and Ground  Temperature
          Observation Sites in Canada                                 2-15
2-9       Ice Deposited by Ocean Waves, Unalakleet, Alaska
          and Ice Deposited by River, Napaskiak, Alaska               2-18
2-10      Building Damaged Because Ice Around the Piling was
          Lifted by Flood Waters, Unalakleet, Alaska                  2-19
2-11      Erosion at Bethel, Alaska, Caused by Flooding of River      2-19
2-12      Deteriorated Roads in Bethel, Alaska,  Caused by Poor
          Drainage                                                    2-21
2-13      Medium Density Apartment Buildings in Godthaab, Greenland   2-23
2-14      Example of Proper Planning                                  2-26
2-15      Self-refrigerating Thermo-piles in Galena, Alaska           2-27
2-16      Sports Complex in Godthaab, Greenland                       2-27
2-17      Open Area Building Construction in the USSR                 2-29
2-18      Aerodynamic Building Design to Reduce Snow Drifting
          Problems, Prudhoe Bay, Alaska                               2-30
2-19      Example of Ice-falling Problems on Building in
          Wainwright,  Alaska                                          2-31
2-20      Problems of Summer Construction on Muskeg, St. Mary's,
          Alaska                                                      2-34
2-21      Temperature Effects on Worker Productivity                  2-34
2-22      Typical Winter Construction Problem, Kotzebue, Alaska
          Cat Fell Through Lake Ice                                   2-35
2-23      Temporary Runway Constructed on Lake Ice, Nondalton, Ak     2-38
2-24      Unloading C-82 Aircraft after Landing on Temporary Ice
          Runway                                                      2-38

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                         List of Figures (con1t)

Figure

 2-25    Cost of Living Comparison for Northern Canada               2-40
                             List of Tables

Table

 2-1     Example of Savings with Proper Planning                     2-26

 2-2     Construction Cost Factors for Alaska                        2-41

 2-3     Costs of Water Distribution and Sewage Collection
         Facilities in Cold Regions (1977)                           2-49

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                                   2-1
2        PLANNING  AND  PRELIMINARY  CONSIDERATIONS
         It  is  advisable  to  apply  the  principals  of  good  planning to
new developments and to extensions of  existing  communities.   Moving to a
new location or rearranging  the  present  layout  according  to  good planning
practices must  be  considered because the  addition of utilities will
"anchor" a community to a specific location.
         Utilities are required  and are  being installed in many existing
communities whose  locations  and  layouts  originated from a subsistence
economy.  They  were located  close  to hunting grounds,  and near the ocean
or rivers for transportation and fishing.  Many of these  locations were
also influenced by the RCMP,  missionaries, Hudson Bay Company outposts,
and government.  Requirements beyond the  immediate needs  were not consi-
dered; population  growth,  utilities, housing, and other modern "essentials'
were usually neglected in the community  location  and layout.   Many of  the
present villages slowly evolved  from a temporary  fishing  or  hunting camp.
For example, nearly all the  Eskimo communities  along the  west coast of
Alaska are located on  sand spits projecting into  the ocean (see Figure
2-1).  These eites suffer  from erosion,  flooding,  lack of room for
expansion, and  long distances to a freshwater source.  The "old timers"
say that they located  there  to be  near the seal hunting and  salmon
fishing, as well as to be where  they could see  and prepare for the
raiding Indians from the  interior  of Alaska.
2.1      Objectives
         The objectives of planning are  to reduce the  cost of construc-
tion, and operation and maintenance (O&M) of utility systems,  while at
the same time, providing  a healthy, functional, convenient,  usable,
attractive community or site.
2.1.1    Health
         The primary purpose  of  providing safe  drinking water and
sanitary waste disposal is to improve  public health  (see  Figure 2-2).
Protection against  water-carried diseases such  as  intestinal  disorders,
hepatitis,  typhoid, polio and cysts, to name a  few is  provided.   Also,
the provision sufficient water for  personal hygiene,  laundry,  and
cleaning of the home reduces  the occurrence of  impetigo and  other  skin

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                          2-2
             FIGURE 2-1.  UNALAKEET, ALASKA.

 The bottom of the picture is Norton sound and the
 water body in the centre is a salt water tidal  slough.
FIGURE 2-2.  ICE STACKED TO BE MELTED FOR DRINKING WATER
             - KOTZEBUE, ALASKA

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                                   2-3
diseases.  A  third  health  consideration  is  drainage  in  and  near  communi-
ties.   Swampy or  low  areas become  contaminated,  stagnant  ponds,  which
support mosquitos and other insects which can  carry  diseases  and be  a
general nuisance.
         Different  degrees of  overall  health improvement  are  accomplished
with various  types  of sanitation facilities [1,2,3],  The provision  of  a
safe source of water  within a  community, but outside  the  home, will
facilitate health improvement.  The improvement  is limited, however,
because:
         1)   It is  impractical  to  have the  source near  all  homes and  many
              people will continue  using  the original  unsafe source,
              particularly  if it is closer.
         2)   Since  all water must  be hauled, it  is used sparingly and
              seldom used for personal  hygiene, house  cleaning, laundry
              or other uses than cooking  and drinking.
         3)   Even though safe  water is supplied  at a  watering point,  it
              often  becomes contaminated  during transport  or storage  in
              the home.
         A considerably greater health improvement can  be accomplished
by safely distributing the water to the  individual users.   Individual
wells are not common  in permafrost areas; therefore,  the  two most common
ways of distributing  water are  through pipelines and  water-hauling
vehicles.  Greater  quantities  of water are made  available and the risk of
contamination during  delivery  is reduced, although the  possibility is
greater for hauled  delivery than for piped delivery.
         In many cold  regions, conditions such as deep  frost, permafrost,
poor soils and rock may preclude the use of individual  outhouses or
septic  tank systems.  Therefore "organized" community systems are
necessary.  In communities where "organized" sewage collection is not
provided, toilet wastes and  grey water tend to be disposed of in an
unsanitary and unhealthy manner.   Several recent hepatitis outbreaks  have
been traced to this problem.  A sanitation facility feasibility  study
conducted for the towns of  Wabasca and Desmarais near Lesser Slave Lake
in northern Alberta,  Canada, showed that a completely subsidized hauled
water system would  provide  the government a return on their investment

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                                  2-4
of at least 62% in one year from health cost  savings  alone  [3,4],   The
discomfort and work time missed because of  intestinal disorders,  etc.,
that would not be reported to  the government-operated hospitals  and
clinics were not considered.
         Cold region communities are usually  isolated;  therefore,  health
problems are usually caused by self-contamination  rather  than  inter-
community contamination.  The health risks  from  discharges  of  domestic
wastes to the ocean or large rivers can be  greatly reduced  if  outfalls
are designed and constructed to protect shellfish  beds  and  the water
source for the individual site or community.   Discharge standards  or  guide-
lines established for heavily populated areas  should  not  be applied
without considering local conditions.  This will avoid  the  installation
of costly treatment schemes which are designed to  provide greater  protec-
tion of water uses than necessary, and which  are usually  far beyond the
ability of small communities to operate and maintain.   Pathogens  have
longer survival times in cold waters and can  be  preserved for  thousands
of years in the frozen state.  Therefore, the  potential public health risk
is greater in cold regions.  However, the low population  density  renders
this somewhat irrelevant for some locations,  especially coastal  areas.
2.1.2    Social/economic
         The World Health Organization (WHO)  has stressed the  importance
of adequate water, sewer, and garbage services to  the economic and social
development of a community.  There will be  poor  health  in a community
without basic sanitation and there is little  prospect of  socio-economic
development without good health.  Sick or incapacitated people cannot
contribute or participate in the labour market.  Moreover,  a healthy
person can relocate to a place of employment  more  readily than a  sick or
unhealthy person.
         Watering points and central facilities  provide a safe community
water supply.  However, commercial or industrial buildings, such  as
hotels, schools or fish processing plants must be  directly  connected  to
the water source by a pipeline.  A sufficient  quantity  of water  cannot be
practically or economically distributed by  truck to large industrial  or
commercial users.  Water and sewer services act  as a  catalyst  to  indus-
trial development.  The location of government centres, canneries  or

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                                   2-5
cold storage plants  is often determined by  the availability of  the
municipal services.
         The provision of sanitary conditions is  probably  the largest
single factor in improving  the  "standard of living"  of  a rural  area.   The
indigenous societies in rural northern Alaska and  Canada are changing
from subsistance to  cash-oriented economies.  The  stresses  of this
transition are major cause  of the high suicide and alcoholism rates  in
northern areas.  Safe water, adequate sanitary facilities  and a healthy
environment will improve productivity and assist  in  this transition.
         The introduction of sanitary facilities  in  a rural community
often provides the initial  contact with such matters as bookkeeping, bill
collection, tax withholding, workmen's compensation  and, usually,
unemployment insurance.  These  along with management and technical
experience, provide  a basis for social growth.  Proper  planning requires
local meetings and decisions, which promote community involvement.
         Participation in the development and implementation phases of
the facilities encourages a feeling of community  ownership  and  responsi-
bility.  The participation  promotes responsible operation and maintenance,
thus increasing the  life of the facility.  If outside assistance,
especially funding,  is needed in a community to provide for the O&M of
the facilities, care should be  taken to preserve  the community's sense of
self-reliance and avoid further dependance on government assistance.   It
is important that outside technical assistance be made available to the
local operators.  There are several different philosophies  as to what
degree, if any, of the O&M costs of facilities should be subsidized by
the government:
         a)  A facility should not be constructed unless it is  competely
             within the community's financial ability to operate, main-
             tain, and manage.
         b)  The entire O&M and management costs should be  subsidized  by,
             or the facilities operated by, the government.
         c)  The facility O&M costs should be subsidized to the extent of
             the savings in health services which are realized  by instal-
             lation of the facility.  In almost all  instances involving
             indigenous people, 100% of the health services are presently
             government-subsidized.

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                                  2-6
         There have been instances where well-intended assistance
programs actually contributed to community disorganization.  Thorough
examination of the social and economic implications of a project are
necessary to select the type and sophistication of facility that is best
suited for a given community.  Legislative, administration, and local
constraints can increase the chance of project failures because they may
limit the types of projects which can be considered.
2.2      Regulations and Legislation
         There are many permits or clearances which must be obtained
before construction can proceed.  This can be time-consuming, and thus
expensive, and must be budgeted into a project in the beginning.  The
major regulations to be followed and clearances to be obtained are listed
below.  Requirements differ in individual Canadian provinces and
territories, and the U.S. in several instances.  Regulations and
procedures change frequently, and it must be emphasized that one should
check with the applicable agencies before proceeding with a project.
2.2.1    Water rights
         In Alaska, the Alaska Department of Natural Resources*
determines water rights and issues water use permits.  They also issue
and administer permits for rights-of-way or easements, use of tidelands,
and special land use on State lands.  In the Yukon and Northwest
Territories, the Territorial Water Boards conduct public hearings related
to applications for water licenses to ensure that a license applicant
submits sufficient information and studies for the Board to evaluate the
quantitative and qualitative effects of a proposed water use, and sets
water quality standards.  Provincial authorities must be consulted for
their regulations and procedures.
2.2.2    Water discharge permits
         Waste discharge permits are required for any discharge (solid or
liquid) to surface or groundwaters.  Permits are issued by the Alaska
Department of Environmental Conservation**.  Further information is
* Division of Land and Water Management, 323 East 4th Avenue, Anchorage,
  Alaska 99501.
**Pouch 0, Juneau, Alaska 99811.

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                                      2-7
available from the U. S. Environmental Protection Agency*, which also
administers oil spill prevention and control plans.
          Any stream supporting anadromous fish in Alaska must receive
clearance from the Alaska Department of Fish and Game**.  Waste dis-
charges in the Territories are regulated by the respective Territorial
Water Boards.  Within the provinces, each authority must be consulted.
2.2.3     Archaeological clearances
          Archaeological clearances must be obtained if excavation or
construction will take place at any possible archaeological sites.  The
Alaska Department of Natural Resources*** administers these clearances
and permits if federal funds are involved.  In the Canadian Territories,
archaeological clearances are dealt with under land use permits.
2.2.4     Environmental assessments or impact statements
          An environmental assessment or impact statement is necessary in
the U. S. for any federally funded or "major" state or private project
changing the environment, for the better or worse.  Which one of the two
is required is usually governed by the degree of the change.
     In the U.S., requirements can be obtained from the U.S. Environ-
mental Protection Agency.  There were requirements for environmental
assessments or impact statements in the Yukon or N.W.T. at the writing of
this manual.
2.2.5     Rights-of-way and easements
          Rights-of-way for construction and O&M must be obtained where
lines will cross private property or other parcels of land not owned by
the constructing agency.  They must include a legal description of the
crossing and be obtained from the property owner.  They must state
exactly what is allowed, and be legally recorded.  In Alaska the U. S.
Department of Interior****, issues rights-of-way across Bureau of Land
Management (BLM) managed lands.  In Canada, these are covered under land
use permits.
*    Alaska Operations Office, 701 C Street, Anchorage, Ak 99513
**   Habitat Protection Section, Subport Bldg.,  Juneau, Ak 99810
***  Division of Parks, 619 Warehouse Avenue, No. 210, Anchorage Ak 99501
**** Bureau of Land Management,555 Cordova, Anchorage, Ak 99501

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                                   2-8
2.2.6    Land use  permits
         Land use  permits  are  issued  by  the  Department of Indian and
Northern Affairs.   The  regulations  are not applicable within the
individual communities.
2.2.7    Safety  standards  during construction
         There are  many  different safety standards.   In the United
States, Occupational Health  and Safety Authority  (O.S.H.A.) standards
usually must be  followed.  However, there are  some  government agencies,
such as the U.S.   Army  Corps of Engineers, which  have their own safety
standards and enforce them.  Within the  State  of  Alaska,  the Department
of Labor* administers safety standards.   In  Canada  these  are covered in
the land use permit.
2.2.8    Structures in navigable waters
         Permits must be obtained before structures  can be  placed near or
in navigable waters.  In the U.S.,  two different  agencies issue permits
depending on the conditions.   They  are the U.S. Army Corps  of Engineers
and the U.S. Coast  Guard.  The Corps  of  Engineers**  issues  permits for
any activity in  navigable  waters and  wetlands.  This is mainly for dredge
and fill operations and  for  the placement of any  structures in navigable
waters.  The U.S.  Coast Guard*** issues  permits for  any bridge construc-
tion over navigable waters.
2.2.9    Safe drinking water regulations
         In the  U.S. the Safe  Drinking Water Act  stipulates the allowable
concentrations of  impurities in drinking water.   The act  is administered
by the individual  state or the U.S. Environmental Protection Agency.  It
is discussed in more detail in Section 4 of  this  manual.   In Alaska, the
Alaska Department of Environmental Conservation should be contacted.  The
Canadian Drinking Water Standards and Objectives, 1968, are similar to
U.S. regulations.   Further information can be  obtained from the Federal
Department of National Health  and Welfare, Ottawa, and from the
Territorial Governments in Yellowknife and Whitehorse.
*   Division of Occupational Safety and Health, P.O.  Box  1149,  Juneau,
    Alaska 99811.
**  P.O. Box 7002, Anchorage, Alaska 99501.
*** P.O. Box 3-5000, Juneau, Alaska 99802.

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                                  2-9
2.2.10   Clearing houses
         The Alaska State Clearing House* clears  projects  for  compliance
with federal regulations, while the Department of Environmental  Conserva-
tion clears projects for compliance with state regulations.  The Alaska
Department of Environmental Conservation must review and approve plans
and specifications of all privately and state-funded water  supply  and
sewerage projects.  It also reviews and comments  on all federally-funded
projects.
2.3      Type of Installation or Site
         Temporary constructions or military camps, resource development
camps, semi-permanent military installations, and new and  existing  cities
or communities are the types of installations present in cold  regions.
The economic base, stability, growth potential and physical permanence of
an installation or community will have very strong influence on  the  type
of utility system which would best serve that community or  site.
Examples of delivery and collection systems are discussed  later.
2.4      Site Considerations
2.4.1    Permafrost
         Permafrost is not a material; it is the  state of  any  material
which stays below 0C for two or more years.  Solid rock in this
state would not usually create an unusual construction problem.  "Beaded"
streams (Figure 2-3) and "frost polygons" (Figure 2-4) are  two indicators
of ice-rich permafrost.  The frost polygon "lines" are actually  ice
wedges, as shown in Figure 2-5.  Marginal or "warm" permafrost is much
harder to work with than cold (less than -4c) permafrost  because
small physical disturbances at the surface have a greater  thermal effect
on the depth of the active layer.  The construction method  used  in
permafrost will depend on the structure or facility being  designed and
the ground stability upon thawing.  The ground's  stability  is  determined
by its moisture (ice) content and soil gradation.
         Active or passive construction methods have been  defined for
application in permafrost areas.  Active construction is essentially the
  Office of the Governor, Pouch 0, Juneau, Alaska 99811.

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            2-10
       '
                      M,

FIGURE 2-3.  "BEADED" STREAM

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                          2-11
,,      ",l*i'"
           '


                                     "'&
   FIGURE 2-4.   FROST POLYGON ON ALASKA'S NORTH SLOPE
                  FIGURE 2-5.  ICE WEDGE

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                                 2-12
prethawing and/or removal of the permafrost or frost-susceptible materials
and their replacement with gravel or some non frost-susceptible material.
Passive construction usually maintains the frozen state of  the permafrost
by construction above the ground on piles, use of refrigeration (such  as
thermopiles), or insulating the ground surface.
         The distribution of permafrost in the Northern Hemisphere  is
shown in Figures 2-6, 2-7 and 2-8.  Definitions of  the extent of the
permafrost at a given location (discontinuous or continuous) are covered
in the glossary.
2.4.2    Location
2.4.2.1  Access.  Access is of prime importance when  selecting a
location for a new community, camp, or installation.  The method, and
thus the cost, of access to a site or community can vary greatly with
remoteness and the factors discussed below.
         Because of  the importance of air transportation, the site  should
provide a suitable location for a runway, considering prevailing winds,
natural obstacles (mountains, etc.) and the availability of construction
materials.  Ships or barges are also a major transportation system  in  the
North, especially for heavy and bulky items.  Consideration should  be
given to whether a deep, protected harbor is available.  If not, could
one be dredged and,  if so, would continuous dredging  be necessary?
Natural beaches suitable for beaching materials must  be available.
Highway and railroad systems are also access considerations in some parts
of the North.  Access roads to main highways and main rail  lines and
availability of construction materials for them are items which should be
considered if a road system is present or planned.
         In most rural or remote locations, snowmachine and dogsled
trails should be considered since they are still important  means of
transportation.
         New developments such as low pressure tire,  off-road vehicles
and air-cushioned vehicles are being tested and may be access considera-
tions in the future.  In northern Canada and Asia  "cat trains" are  used
to deliver materials in the winter.  These often travel on  frozen river
and lake surfaces.   They may be especially useful  in  delivering

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                                    2-13
             120
150
180
150
                                                                           30
            120                           90                          60
    FIGURE 2-6.   AREAL DISTRIBUTION OF PERMAFROST  IN THE NORTHERN HEMISPHERE

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                              2-14
0 kilometres
b
BARROW
                                                             PRUDHOE BAY
                                                  Southern limit of
                                                  continuous permafrost

                                                  Southern limit of
                                                  discontinuous permafrost

                                                  Mean annual air isotherm (C)
              FIGURE  2-7.  PERMAFROST  IN  ALASKA

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                                                                                Southern kmrt of

                                                                                continuom parmglrMI
                                                                                                            I
                                                                                                           I'
                                                                                                           <_n
FIGURE  2-8.   DISTRIBUTION OF PERMAFROST AND GROUND  TEMPERATURE OBSERVATION SITES IN CANADA

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                                 2-16
materials or equipment  for initial construction  before  permanent  access
routes can be developed.  Information concerning  construction  and main-
tenance of ice roads is available from  the State  of  Alaska,  Department of
Highways, and the U.S.  Army, Cold Regions Research  and Engineering
Laboratory (CRREL)  [7,8,9],
2.4.2.2  Soil conditions.  Another very important consideration in
locating and assessing  a site, camp, or community is the local soil
conditions.  A complete soils analysis  of  the  site is important and  must
include:
         1)  percent of soil passing and retained on various sieves;
         2)  accurate in-place moisture or ice contents;
         3)  penetration rates;
         4)  shear  valves ("vane" shear tests  on  organic soils, etc.);
         5)  chloride content and freezing point  at  different  depths;
             and,
         6)  organic content.
Surface vegetation  can  be helpful in predicting  subsurface  conditions
[6].  Also, soil conditions can  vary considerably over  a short distance.
         Temperature profiles are extremely  important;  however, few  sites
have instrumentation and temperature records.  These should be obtained
as soon as possible.  Thermo-couple or  thermister strings are  usually
used [10],  Information has been published on  their  installation and
monitoring.  Temperature information will  indicate presence or absence of
permafrost, ground  temperatures, and the depth and temperature variation
of the active layer.  The changes expected in  active layer  and ground
temperatures due to disturbances of the surface  vegetation  cover must  be
taken into consideration.
         It is usually  best to avoid permafrost  where possible, by
selecting south  slopes  in discontinuous permafrost areas, or by selecting
locations near large rivers or lakes which have  thawed  the  permafrost
over time.  To lessen the resulting settlement and instability when
permafrost thaws,  sites having soils with  low  or no ice content should be
selected.  These are usually well-drained, coarse-grained soils, rather
than fine-grained  marshy soils.

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                                  2-17
         Frost heaving  and  jacking  must  be  considered  in both permafrost
and non-permafrost  areas.   A frost-susceptible  soil  has been defined as a
soil having more  than 3 percent  passing  a no. 200  sieve.  However,
moisture content  also has much to do with frost heaving.  Piling must be
imbedded in the ground  to a depth sufficient  to resist the upward pull
created by the freezing of  the active  layer.  Considerations for frost
jacking and heaving will not  be  covered  in  detail  in this manual [11,12].
         The prevention of  seasonal freezing  under a structure in a
non-permafrost area would be  one method  of  solving frost heave problems.
The subsurface soil analysis  and depth to bedrock, if  present, will help
determine the types of  foundations  possible for a  given structure.  In
permafrost areas, the possibilities are  essentially  piling or gravel pads
with the final choice depending  on  the availability  of materials (gravel
and/or piling) and  the  permafrost temperature.   Several studies [13] have
demonstrated reductions in  gravel depth  are possible with the addition of
layers of plastic foam  insulation.
2.4.2.3  Topography.  Topography should  also  be considered when
selecting the best  site for an installation,  building, camp or community.
The site should be  sloping  so it will  drain (about 1 percent).  Natural
obstacles which would promote snow  drifting should be  avoided.  Most
communities in the  North are  located along  rivers, lakes, or the ocean
and flooding is often a problem.  Serious consideration must be given to
its frequency and extent, its cause (ice jam, precipitation, etc.) or
whether or not there is current  and ice  chunks  which would cause damage
to surface structures.  (See Figures 2-9 and  2-10.)   Erosion by rivers or
wave action and/or  thermal  erosion  are sometimes significant (Figure
2-11) and should  be considered when selecting a site.   South facing
slopes receive more incident  sunlight  and solar energy, in addition to
providing better  protection from colder  north winds.
2.4.2.4  Resources.  An important item in selecting  a  location is the
availability of potable water.   This will be  discussed in detail in
Section 3 (Water  Sources).  The  quality  and quantity of water source must
be evaluated, realizing that both will change with the seasons of the
year.  Late winter  or early spring  is  the critical time for any surface

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                             2-18
   FIGURE 2-9a.   ICE CHUNKS  DEPOSITED  BY  OCEAN
                 WAVES, UNALAKLEET, ALASK
FIGURE 2-9b.  ICE DEPOSITED
BY RIVER, NAPASKIAK,  ALASKA

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                           2-19
FIGURE 2-10.
BUILDING DAMAGED BECAUSE ICE AROUND THE PILING
WAS LIFTED BY FLOOD WATERS, UNALAKLEET, ALASKA
     FIGURE 2-11.
     EROSION AT BETHEL, ALASKA, CAUSED BY
     FLOODING OF RIVER

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                                 2-20
or shallow groundwater  source.  Recharge  from  precipitation through the
surface is essentially  non-existent.  When  ice thickness  on lakes and
rivers is at a maximum, most of the impurities that  were  in the water are
concentrated in the remaining water under the  ice.   In  many cases, it
becomes unfit for domestic use.  Water absorbs tannins  or lignins from
the mosses and lichens  as it seeps through  the tundra  surface in the
summer [14],  Thus, the best quality water  is  usually  obtained in spring
when the melting snow flows over the still  frozen  ground  surface.
         Energy sources available locally,  such as hydropower, wood,
coal, oil and natural gas, should be considered in selecting a site, as
well as the logistics and cost of importing  fuel.
         A very important consideration in  site selection is the
availability of local construction materials.   Probably the most
important materials are sand and gravel.
         Almost any structure or facility will need  gravel and sand for
foundation pads, backfilling around pipes, making  concrete and building
paths, and airstrips.   In many communities  along Alaska's west and north
coast, gravel is non-existent.  In Bethel,  for example, barges must go
over a hundred miles upriver to obtain coarse  sand,  and farther for
gravel.  It is sometimes less expensive to  barge gravel from Seattle at a
cost of about $26/cubic metre.  If bedrock  or  hardrock outcroppings are
present, they can be blasted for "shot rock" and crushed  for fill.  Trees
suitable for building logs, lumber and piling  can  be an important construc-
tion material, and reduce dependence on importing.
2.4.3    Layout
         The topography must be considered  when laying  out facilities.
The slope of the site should be utilized  to  prevent  ponding of water.
Stagnant water becomes  polluted and provides mosquito  breeding grounds, both
of which can create health problems.  Ponding  also causes thermal degrada-
tion of permafrost.  Snow drifting problems  should be  avoided in the
location and design of  structures.  Airports should  be  located to allow
for future expansion.   Most will start with a  single strip and develop a
cross-runway as needed.  The runway should  be  oriented  with the prevail-
ing winds and above the surrounding terrain to reduce  snow drifting.

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                                 2-21
         Tank farms should be  located away  from  the  community,  and  water
sources protected  from possible oil contamination  by diking  or  some other
means.
         Like runways, if the  roads are built  above  the  surrounding
terrain they will  usually blow free of snow, thus  reducing  snow removal
efforts and costs.  Therefore, cuts should  be  avoided where  possible.
Roads should be constructed up and down the  slope  where  possible.   Roads
constructed across the slope inhibit drainage  and  act as dams.   The
backed up water will cause ponding, and saturate and destroy the roadway
subbase and even building foundations uphill from  the roads  (see Figure
2-12).  Culverts placed through roads to prevent ponding will usually
fill with ice at breakup time  when they are  needed the most.  They  can be
steam thawed just  before breakup but this is expensive and  time consuming.
The most satisfactory solution is to eliminate the problem by orienting
the roads up and down the slopes.
         \
           FIGURE 2-12.  DETERIORATED ROADS IN BETHEL, ALASKA,
                         CAUSED BY POOR DRAINAGE

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                                 2-22
         It is not advisable to design layouts with dead  end  roads.
Because of the need to circulate water mains in cold  regions,  dead ends
are difficult and expensive to service.  Snow removal  is  also  more
difficult.  Roads should be designed so there is ample area to place  snow
plowed from the road.  Docks provided for loading and  unloading barges or
ships should be designed to withstand tides, ice movement, spring floods,
and erosion.
         The importance of thorough soils analysis was discussed earlier,
but additional borings should be taken throughout the  site.   The size and
complexity of the utilities or structures to be built  and the  variations
in the ground conditions will determine the number of  soil borings
necessary and the years of record desirable to determine  groundtempera-
tures.  More structures have failed because of inappropriate  foundation
design, probably due to inadequate soils testing, than for any other
reason.  Additional borings should be taken to better  define  the soils
underlying each building at the site.
         Several factors should be considered in locating buildings.
Consideration should be given to moving existing structures to provide
more functional and useful layout.  Taller buildings  should be located so
they do not "shade" smaller ones from either sun or wind.  Where snow
drifting is a potential problem, placement of small structures on the
windward or leeward sides of larger ones must be avoided.  One storm
could completely bury a conventional size house located leeward of a
large building or storage tank.  The size of snow drifts  can  also be
reduced by orienting buildings so the long axis is with the wind.
         The community layout should be as compact as  practicable to
reduce utility construction and O&M costs (see Figure  2-13).   Utilidors
with central heating lines can cost $2000 per metre,  and  buried water and
sewer lines $1000 per metre.  Placing unserviced areas and large open
spaces such as parks, school playgrounds, and industrial  yards on the
outskirts of a camp or community is recommended.
         A typical cost breakdown for a northern utility  project
(utilidor extensions in Inuvik, N.W.T.) is 50 percent  for construction,
33 percent for materials (on site), and 17 percent for engineering (7
percent for design and 10 percent for inspection).

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                                 2-23
          FIGURE 2-13.  MEDIUM DENSITY APARTMENT  BUILDINGS  IN
                        GODTHAAB, GREENLAND
         An evaluation of existing  communities  in the  Northwest
Territories provided  the following  approximate  figures  for  the length of
water and sewer lines required:
Community Population
Length of water line plus sewer
  line per capita* (metres)	
Less than 300
300 to 600
600 to 1000
1000 to 2500
Greater than 2500
              8
              7
              6
              4.5
              3.5
* These figures are based on five persons per residence  and  do  not
  include service lines.  They are also based on utilidor  systems or
  systems with the water and sewer lines in the same  trench.
         Alaskan experience differs somewhat.  The  systems installed
are usually buried pipes with water and sewer lines in separate trenches.
The figures above should be increased 1.5 times for Alaskan  communities.
         Seventy-five percent of the above pipe lengths  was  water and
sewer together, 15 percent was sewer line only and  10 percent was water
line only.  These figures should be used for rough  estimates only.  Actual

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                                 2-24
conditions will make adjustments necessary,  for  instance,  for a community
that is spread out along a  river.  A community of  200  persons could be
estimated to have 1600 m of water and  sewer  lines.   One  thousand
two-hundred metres would be water and  sewer  together (600  m of water and
600 m of sewer), 160 m would be water  line only  and  240  m  would be sewer
line only.
         For a well laid out site, the  following lengths of pipe per
capita are provided as a guide:
         Single family subdivision           3 to 4 m/capita
         Multi-family area                   0.2  to 2 m/capita
         Apartment area                      0.02 to  1  m/capita
         A compact layout may make a central heating plant practical,
and this can reduce heating costs by reducing energy consumption.   The
risk of fire, which is a major cause of accidental deaths  in cold
regions, is also reduced.  Most home fires are caused, directly or
indirectly, by heating stoves and a central  plant will eliminate the need
for these.   The main disadvantage of  central heating  is the difficulty
of expanding the core system when the  community  or camp  unexpectedly
expands.  Heat is also lost during transmission.  Heat loss is much
higher with above-ground distribution.
         Service lines are  the source  of most water  distribution and
sewage collection line freezing problems.  Buildings should be located
as close to the utility lines as possible to minimize  service line
lengths.  If the water and  sewer lines  are to be placed  in the street  or
alley rights-of-way, the buildings should be placed  on the lot within
18 m of the lines, if possible.
         There are advantages to placing the main lines  along rear lot
lines in a right-of-way.  The snow is  usually not removed, as it would be
in the street, providing warmer ground  temperatures.  In non-permafrost
areas the frost penetration is usually  significantly greater under snow
cleared or packed areas.  They are also not  as likely  to be damaged by
vehicles.  Service lines to both rows  of houses  are  shorter because the
rights-of-way for alleys or utilities  do not need to be  as wide as the
streets in front of the lots, and houses can be  placed close to service
lines since "back yards" are not used  very much  in northern communities,

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                                 2-25
especially in the winter.  Manholes, lift stations and valve-boxes  can  be
terminated above-grade, making maintenance easier.  Also, with  above-
ground utilities the service connection will not require a  road crossing.
         Figure 2-14 and Table 2-1 show an example of the savings
possible when the layout of a community is properly planned.
2.4.4    Energy
         Energy is expensive and requirements are high; therefore,
facilities must be designed to conserve energy.  One example  is to  install
heat exchangers on the cooling water jacket and exhaust stack of power
plants, which can more than double the total energy extracted from  fuel
oil.  Usually only 30% of the fuel energy is used.  The cold  temperatures
can also be used as a resource.  Examples of this are self-refrigerating
thermo-piles (Figure 2-15), desalinization using the freezing processes,
and ice roads.
2.4.5    Utilities
         Utility systems must serve the "total" community.  For example,
it is not economical to have several small generators serving separate
buildings or complexes when one larger unit could serve the entire
community.
         In planning communities or camps, it is important  to provide
recreation facilities which can be used during  the long, dark,  cold winters
(Figure 2-16).  These facilities reduce the social and psychological
problems ("cabin fever") prevalent in isolated, cold regions.  Communities
or camps should have large buildings such as gymnasiums and arenas  that
can be used for basketball, volleyball, curling, hockey, and  other  popu-
lar indoor games.  Swimming pools can also be a very worthwhile addition.
Very few of the indigenous people have learned  to swim, even  though they
continuously use the ocean and rivers for transportation, because of the
low water temperatures, even during the summer.  Swimming pools could
remedy this in addition to providing exercise and recreation  during the
winter.  A useful side benefit to having a swimming pool in a school or
recreation complex is that it can double as a fire protection reservoir,
which is usually an important but expensive addition to buildings in cold
regions.

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                                   2-26
                               Water
                                                        Highway
                                      Road crossing
                                      over utilidor
                                    Utilidor
                                                                       -. r Water
Original development proposal
Improved development proposal
                   FIGURE 2-14.  EXAMPLE OF PROPER PLANNING
              TABLE  2-1.  EXAMPLE OF SAVINGS WITH PROPER PLANNING
ITEM ORIGINAL IMPROVED DIFFERENCE
MGn8oh ^ , N 1936 1887 49
New Roads (m)
Utilidor 191? 1646 2?1
Length (m;
Road 10 6 4
Crossings
Water System A ? ?
Loops
Approximate uo 152 ^
Lots
Junctions ~ 1 1 1
& Bends
TOTAL
NET SAVINGS
(1973 DOLLARS)
3,000
109,000
40,000
2,000
84,000
2,000
$240,000

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                      2-27
FIGURE 2-15.  SELF-REFRIGERATING THERMO-PILES IN
              GALENA, ALASKA
FIGURE 2-16.  SPORTS COMPLEX IN GODTHAAB, GREENLAND

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                                 2-28
         Most communities and camps in cold regions are  remote  with  only
intermittent service, even by air, from larger population  centres.
Therefore, it is very important to provide complete standby  for all
essential components of any utility.  Alarms and  safeguards,  such as low
water temperature alarms, low flow alarms, and low or high voltage
alarms must be provided to warn operators of any  pending problems.   The
importance of a reliable, knowledgeable operator  will be discussed later.
         Longer lead times must be allowed when requesting utility
services.  Requests for electrical service to a project  site  must be made
to the local electric utility.  In most remote Alaskan communities this
is the Alaska Village Electric Corporation.  In the Northwest and Yukon
Territories, it is usually the Northern Canada Power Commission.
         When constructing a building or facility requiring  water and
sewer service, notice should be given well ahead  of when the  service is
needed.  It may be necessary to expand the source or storage, which  could
mean bringing materials in on the one and only barge per year.
2.4.6    Building design
         Buildings should be designed for multiple use wherever possible.
It is expensive to heat and maintain a building continuously when it is
only used a few days each week (such as a church) or part  of  the day
(such as a school).  Medium height cubical buildings should  be  used
rather than low and spread out types.  They are more efficient  from  a
heat loss standpoint and provide a more compact arrangement  for utility
service.  There is somewhat more danger in case of fire, but  fire
protection must be designed into any building.  Open areas with plants
are important from an exercise and psychological  point of  view, and  have
been provided in  large buildings in the USSR  (Figure 2-17) and  Prudhoe
Bay, Alaska.
         Windows  are necessary but they are a high heat  loss and main-
tenance  item and  should be designed to provide the most  benefit with the
smallest area.  Window orientation toward the south, multiple glazing,
and wood casings  maximize insulation and energy  savings.  Windows  extend-
ing above or below eye level should be avoided but it  is important  to be
able to  see out sitting or standing.  Windows are of no  value during

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                                 2-29
        FIGURE 2-17.  OPEN AREA  BUILDING CONSTRUCTION IN  THE  USSR
darkness, therefore,  insulated shutters should  be  provided  to reduce  heat
loss.
         Buildings should be well-insulated  to  minimize  the  total annual
cost of heat and amortization of the  insulation costs.   (See  Section  14).
Vapor barriers are also a very important part of any  building in  cold
regions.  Information is available concerning vapor barriers  and  types  of
insulation suitable for different applications  [15,18],   Insulation must
be kept dry.  Absorption of 8 percent moisture  (by volume)  will  reduce
the  insulating value  by one-half.  An impermeable  or  low  water absorption
insulation should be  used in damp or  wet locations.   The  reduction of air
exchange is as important as insulation in reducing building  heat  losses.
Some air exchange in  a room or building is necessary.  Quantities vary
with use and are usually stipulated in building codes, but  anything over
these minimums should be avoided.
         In areas where snow drifting is a problem, aerodynamic  design  of
the building exterior can reduce drift size, and also move  the drifts
which do build up further from the building  [16] (Figure  2-18).

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                                              2-30
Permafrost table
              Top of tundra
                                                            Steel roof truss
                                                                      Stud bearing walls

                                                                                  Plywood & joist floor
                                            Concrete slabs
                                               /I   Steel beam
                                                                                    Steel skid
                                                                                  Concrete pile caps
                           Steel piles .' 
                        ' .  30' below grade
                                   Transverse Section through Composite Building
                                     r
f\. Rectangular-section building

                                                      B. Rectangular-section building with
                                                         leading edge rounded to a half cylinder
                                                 	    C.  Final building form
              FIGURE 2-18.   AERODYNAMIC BUILDING DESIGN  TO  REDUCE  SNOW DRIFTING
                             PROBLEMS,  PRUDHOE  BAY,  ALASKA.

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                                  2-31
         Building  entrances  should  not  be  placed  in  the  windward or
leeward sides of buildings.   If  possible,  all  doors  should be double
doors with a space between them  large enough  so one  is  closed before the
second one is opened.   This  will  greatly reduce the  air  exchange when
going in or out of the  building.  All doors and entrances  must be
protected from snow and  ice  falling  from the  roof  (see  Figure 2-19).
Serious accidents have  been  caused  by ice  falling  on someone leaving a
building when a door  is  slammed.
         Roofs probably  cause more  problems than all other building
components combined in  cold  regions.  Hip  roofs should  be  used if
possible, with flat roofs being  the  last choice.   It is  very important
that all roofs be well  insulated  and provided  with a very  tight vapor
barrier [17].
         Building heating systems must  be  as  fool-proof  as possible with
standby pumps and boilers provided  for  emergencies.   Hot water circulat-
ing systems in remote, cold  region  areas should be charged with a glycol
            FIGURE 2-19.
EXAMPLE OF ICE-FALLING PROBLEMS ON
BUILDING IN WAINWRIGHT, ALASKA

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                                 2-32
solution, but this must be taken into account in  the  sizing  of  boilers,
pumps, expansion tanks and other system components  [18].
         Humidity is an important consideration in  cold  regions,  especially
inland.  Humidity drops extremely low with cold winter weather.   For
comfort, as well as to prevent damage to  furniture,  the  humidity  should
be kept at about 30 percent by using humidifiers.   High  humidity  (above
50 percent, depending on temperature) can cause equally  as numerous and
serious problems due to condensation on windows,  walls and in  insulation.
During warm spells or in the spring this  frozen condensate can  ruin
paint, insulation, and even destroy the building  by inducing wood rot.
In very humid areas, such as pumphouses or sewage lift stations,  moisture
control or dehumidifiers are necessary.
         Building foundations will not be covered in  this manual  but
information is available elsewhere to help the designer  with this most
crucial component of building design in cold regions  [19,20,21],
2.4.7    Revegetation
         Revegetation will usually be required where  the natural
vegetation has been damaged or removed by construction.  It  is  necessary
to prevent erosion and make the site more aesthetically  pleasing. The
purpose of seeded plants is primarily to  provide  some growth to  protect
the soil until the natural vegetation returns.  The U.S. Soil  Conserva-
tion Service and the Alaska State Division of Aviation have  developed  the
following recommendations for seeding tundra areas  [22].  The  best time
for seeding is before mid-summer and after break-up.  However,  scattered
seeding has been successful even when the seeds were  broadcast  on the
snow in the spring.  The grasses will probably die  out in four  to five
years but the natural vegetation should be well on  its way to  recovery by
then.
         Recommended seed rates are:
         1)  Meadow Foxtail (common) = 22.4 kg/ha
         2)  Hard Fescue (Durar) =22.4 kg/ha
         3)  Red Fescue (Arctared) = 33.6 kg/ha
         4)  Annual Ryegrass (Loliun Multiflorum) = 33.6 kg/ha
             TOTAL = 112 kg/ha

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                                 2-33
         The mixture should be seeded, and fertilized immediately and  at
the beginning of the second year with the following fertilizers and
rates:
         1)  10-20-10 - 448 kg/ha,
         2)  33-0-0   - 112 kg/ha.
2.5      Project Management
         Project management is an extremely important part of  planning
for remote, cold regions installations.
2.5.1    Construction season
         The length of the construction season varies with factors such
as soil conditions, length of daylight, and climate.  However, construc-
tion cannot start in any location until the materials and equipment are
on-site.  Barges normally arrive in Barrow, Alaska and  the Eastern Arctic
around the first of September, which is near the end of the construction
season.  This means that materials must be shipped one  year in advance
for construction to start the following summer.  The length of the normal
construction season varies from two to three months along the Arctic
coast, to six or eight months in more southern areas.
         Some soils, such as low moisture contents sandy-gravelly soils,
can usually be excavated more easily when frozen.  When they are thawed,
shoring is necessary to prevent the trenches from caving in.   Some muskeg
or highly organic soils are also easier to excavate in  the frozen
condition (see Figure 2-20).  When thawed, such soils often will not
support equipment or even people.  On the other hand, saturated gravelly
silts are nearly impossible to dig when frozen and must usually be either
thawed or blasted.
         The weather (temperature, wind, snow, rain, etc.) greatly
affects the amount of work accomplished during a constrution period.
Studies have indicated that temperature affects workers and equipment  as
shown in Figure 2-21 when other environmental factors are considered
ideal.  Darkness, wind and rain will reduce productivity further.  The
effects of cold temperatures on oils, diesels, antifreeze solutions,
steels, woods, and plastics are shown in Appendix A.  It is important
that these be understood before cold temperature construction  is attempted,

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                          2-34
    FIGURE 2-20.
PROBLEMS OF SUMMER CONSTRUCTION ON

MUSKEG, ST. MARY'S, ALASKA.
    100
  o

  0)
 'o
  c
  0>

  a
  Q)
 0.
                                                    -40
FIGURE 2-21.  TEMPERATURE EFFECTS  ON  WORKER PRODUCTIVITY

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                                 2-35
         The lack of light can be partially corrected  by using  artificial
light.  A chart showing  the hours of daylight at various latitudes  is
included in Appendix H.  Daylight values will be shortened,  of  course,  in
a location having mountains or other local terrain variations.
         More and more contractors in cold regions are attempting winter
construction of buildings to stretch out the construction  season and take
advantage of lower transportation and equipment costs  with cheaper  and
more available labour.   Concrete work must be kept warm and  aggregates
must be kept from freezing or thawed before use.  Excavation should
usually be done before the ground freezes.  (See Figure 2-22).
           FIGURE 2-22.  TYPICAL WINTER CONSTRUCTION  PROBLEM,
                         KOTZEBUE, ALASKA
         Winter construction can create severe moisture  problems  in
buildings.  Portable heaters used to keep the interior warm  produce
considerable amounts of water in the combustion process  and, unless  they
are vented to the outside, this water accumulates in  the building
interior where it can cause problems for years to come.
         The decision must be made as to whether to work longer hours and
pay overtime, or extend construction into the winter  and/or  another

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                                 2-36
construction season.  This is an economic consideration which may  depend
on weather, overhead costs, and other local conditions.  Also,  studies
have shown that working overtime for an extended period of  time is not
cost effective.
2.5.2    Transportation
2.5.2.1  Methods of shipping.  Construction materials and equipment are
delivered to many construction sites by barge or ship.  It  is very
important to investigate the following items to avoid delays in project
construction.
         1)  The number of sailings per year and the chances of
             nondelivery due to shore ice not moving out, rivers being
             too low, or other natural factors should be known.
         2)  Delivery schedules should be determined so that materials
             and equipment can be at dockside at the point  of disembark-
             ment.  There is usually a specific and limited period of
             time during which materials will be accepted.
         3)  The rates charged and the criterion that they  are  based on
             (volume or weight) should be checked.  There often are
             demurrage charges on shipping company containers.   Rates  for
             barge transportation have steadily increased over  the past
             few years.  There is also a daily charge for non-scheduled
             stops (communities not normally on the route).
         4)  On many scheduled barges space must be reserved in
             advance.  It is important to check the capacity of barges
             serving the area and the capacity of off-loading docks and
             equipment before ordering materials and equipment.
         5)  Chartering barges should also be considered.   The
             economics of chartering will depend on the amount  of
             materials to be shipped and whether the location is a
             scheduled stop on an established route.
         6)  The facilities available for off-loading at the site
             should be determined.  If there are no docks,  are  there

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                                 2-37
             suitable beaches for beaching  the  barge?  What  equipment
             (such as cranes, trucks, cats, etc.)  is available?   Can  the
             barge or ship be brought into  shore or must  landing  barges
             be used to shuttle materials between  the  ship and  shore?
             Ship or barge landings or docking  must usually  be
             coordinated with the tide.
         Air transportation is becoming more and more  competitive in
cold regions and is the only transportation method to  some sites  in  the
Arctic and Antarctic.  The following should be  investigated:
         1)  The landing strip capabilities should be  determined. Is
             the strip useful year-round or just in the winter?   Even
             year-round strips usually have seasonal limitations, such as
             soft spots in the spring and cross-wind limitations, depend-
             ing on the aircraft.  Temporary strips can be constructed on
             lakes or river ice or on compacted snow during  the winter
             [9] (Figures 2-23 and 2-24).  Lake ice is usually  smoother
             than river ice and is thus suited  for a wider range  of
             aircraft and heavier loads.  Equipment must  be  available
             locally or brought in to construct ice or snow  landing
             strips.  Some other items which must  be considered are:
             runway length, approaches, type of surface,  navigational
             aids, runway lights, and elevation.
         2)  A check should be made into the available aircraft and
             their capabilities.  Size limitations, which are usually
             defined by the size of the loading door and  cargo  space, and
             weight limitations must be determined for the different
             sizes and kinds of planes.  The costs (both  flying time and
             standby time) are needed, along with  the  performance
             limitations for each plane.  Some  planes  require special
             fittings for use on gravel strips.  What  type of facilities
             for loading and unloading are available at the  site?  The
             available facilities should be compared with the
             requirements of the aircraft.

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                        2-38

FIGURE 2-23.  TEMPORARY RUNWAY CONSTRUCTED ON LAKE ICE,
              NONDALTON, ALASKA
FIGURE 2-23.  UNLOADING C-119 AIRCRAFT AFTER
              LANDING ON TEMPORARY ICE RUNWAY

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                                  2-39
         Similar  considerations  are necessary  in  areas  served  by roads
and/or railroads.  Are  the  roads useful  year-round  or are  they seasonal,
and do they carry load  restrictions during  the  spring?   Rates  by the
weight or volume  and  the  size  and weight  restrictions must  be  considered.
A check on demurrage  charges on  railcars  or  containers  should  be made.
2.5.2.2  Transportation costs.   When  comparing  the  benefits and costs
of the different  methods  of transportation  available, consider:
         1)  the  gain in  construction time  achieved by  using air
             transportation;
         2)  the  number of  times the  materials  and  equipment must be
             handled  (the amount of shipping damage is  directly related
             to the number  of  loadings or off-loadings  needed);
         3)  the  true shipping costs  (i.e.,  including demurrage cost,
             lighterage costs  and long-shoring);
         4)  the  difference in costs  for  chartering vs.  using  scheduled
             carriers for any  alternative.
         Cost adjustment  indexes have been  developed for the cold
regions of North  America.   Figure 2-25 shows a  Canadian  cost of living
index with an index of  1.0  based on construction  in the  Great  Lakes  area
[23].  Table 2-2  indicates  construction  cost factors for Alaska for  the
construction of repetitive  type  facilities,  such  as buildings, with  an
index of 1.0 assigned to Washington,  D.C.
         The Alaskan  and  Canadian cost indexes  cannot be directly
compared because  the  Alaskan index is for straight  construction costs
while the Canadian index  is only a "cost  of  living" comparison between
different points  in northern Canada.
2.5.2.3  Shipping  considerations.  Because  of harsh environment,  the
shipper's or carrier's  liability for  loss and damage of  the shipment must
be investigated.   Loss  or damage of one  important component could delay
completion of the  project for  one year or more.  Materials  and equipment
must be packed to  prevent damage during  shipment.   Crating  and protection
needed during transit must be  specified.  Items usually  must be handled
several times.  Also, they may be vulnerable to salt water  while  on  barges.

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                                                                 Level of
                                                                 suggested Xtowince
                                                                                          NJ
FIGURE 2-25.   COST OF LIVING COMPARISON FOR NORTHERN CANADA

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                                 2-41
            TABLE 2-2.  CONSTRUCTION COST FACTORS  FOR  ALASKA
NOTE:  The following location factors are applicable  to  the  construction
of repetitive type facilities, such as dormitories, dining halls,  BOQ's,
administrative buildings, fire stations, warehouses etc., which  make
maximum use of local skills, materials, methods  and equipment.   They  are
not applicable to more complex facilities.

       The location factors are multiples of  the  basic value of  1.0
assigned to Washington, D.C.

Taken from U.S. Air Force Publication 83-008-1,  Dated 3/1/62
LOCATION
                        FACTOR
Aleutian Islands
Adak
Attu
Cold Bay
Dutch Harbor
Shemya
Anchorage
Barter Is., North Coastal Area
Bethel
Clear
Coastal Area, North of Aleutians
Eielson AFB
Elmendorf AFB
Fairbanks
Fort Greely (Big Delta)
Fort Yukon
Inland Area, North of Aleutians
Juneau
Kanakanak
Kenai Peninsula
Kodiak
Kotzebue
Naknek
Nome
Northway, Highway Area
Point Barrow
Tanana
Whittier
Seattle
Galena*
3.0
3.0
3.0
3.0
2.5
3.1
1.7
5.2
3.8
1.7
3.5
1.9
1.7
1.9
2.2
2.6
4.0
1.8
2.1
2.1
2.5
3.0
2.1
2.3
2.3
4.6
3.2
1.9
1.0
3.0
* Building cost (heated)
  50 000 ft2.
$150/ft2 with 3 stories and

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                                 2-42
Items such as foam insulation components, paints, polyelectrolytes,
adhesives and other materials must not be allowed to  freeze.
2.5.3    Equipment
           The type of equipment purchased and the careful  preparation  of
equipment for cold weather work are very important time and money savers.
         Equipment must be in top shape before it is  sent to  a  remote
location.  Equipment and tools for repair are usually limited in remote
areas, and importing mechanics and parts is expensive in addition to  the
cost of "down time".  A large inventory of critical spare parts is
recommended and standardization of equipment to reduce the  parts
inventory will prove economical.  Standby units should be provided  for
critical equipment so the job is not stopped completely.
         Equipment should be planned carefully before the initial ship-
ments to the job site, especially large pieces that cannot  be flown in  at
a later date.  For mobility, select equipment that can be flown from  one
location to another in the available aircraft.  Equipment selection for
the conditions that will be encountered, such as heavy-duty rock buckets
for digging frozen ground, and grousers on backhoes,  is important.
However, equipment selected should not be too highly  specialized in order
to reduce the number of pieces needed.  Preventative maintenance is
extremely important.  Schedules should be established and adhered to.
Good maintenance records are important as they will:
         1)  provide back-up data when the time comes to decide which
             brand of equipment to select for future  projects,
         2)  help pinpoint weaknesses and reduce the  spare  parts
             inventory,
         3)  provide checks to ensure that preventative maintenance is
             being performed on schedule.
         The initial cost of a piece of equipment is usually  not as
important as its reliability.  Equipment should be selected for which
there are reliable dealers with adequate parts inventories, service
facilities and staff nearby.

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                                  2-43
 2.5.4     Labour and inspection
          Labour costs are presently escalating at a higher rate than
 material  costs and now attribute to 50% of a project's total expenses.
 Studies and  experience indicate that it is better to use local labour
 whenever  practical.
          There are several reasons for this:
          1)   Local people are more familiar with, and adapted to,
              local conditions, including weather.
          2)   If they live near the project site, camp facilities will not
              be required.
          3)   If they live in the community receiving the facilities they
              have  more at stake because they have to live with the final
              facilities.   Knowledge gained during the installation will
              also  facilitate repairs.
          4)   Local hiring provides an  economic boost to the area in
              addition to  the benefits  provided by the project.
          5)   Local people can be trained as equipment operators,
              carpenters,  and plumbers,  which will help them obtain jobs
              in the future.   Productivity of these trainees is usually
              lower than experienced labour.
          There are some special problems which must be kept in mind:
          1)   In some locations there are not enough skilled and
              reliable workers.
          2)   Local customs and politics must be recognized and honoured.
          3)   Supervisors  and specialists will probably still have to  be
              imported.  They must  be selected carefully,  and they must be
              able  to work and communicate  with the local  people.  They
              must  also  be willing  to tolerate the remote  conditions.
              This  hardship is usually  offset by high wages.
          4)   Union contracts may preclude  using non-union local labour.
          Safety precautions  are very important in cold,  remote locations
because of the  distance to hospital  facilities and the  harshness of the
weather conditions.   In cold weather, workers should use  the "buddy

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                                 2-44
system" whether working or traveling.  This way  there  is  always  someone
to help in case of an accident.  Inspection methods and  frequency  are
extremely important.  A small mistake, or a case of poor  workmanship can
cause an entire facility to fail.  Once equipment  is removed  it  is very
expensive to return it to repair mistakes.  Thorough inspection  is even
more critical when the contractor is from the  south and  not  familiar with
the problems of cold regions.  Inspectors should keep  in  mind  the
following items:
         1)  All irregularities or possible problem areas in  the field
             should be documented immediately.   Polaroid  (or  equal)
             photographs will enable the inspector to  mark discrepancies
             immediately on the photograph, and  he can see that  he has a
             good picture at the time he takes it. Also, thorough daily
             written reports and verbal communications with  the
             supervisor and/or contract officer  are extremely important.
         2)  Changes from the original design  must be  recorded accurately,
             and as-built drawings of the project  prepared.
         3)  The contract documents must be thoroughly understood, and
             who has authority to make changes.   It is important that  the
             inspector does not permit changes in  the  field  that he is
             not authorized to make.
         4)  Regular contact with the project  engineer and contracting
             officer must be maintained.  They should  be well-informed as
             to problems and progress of the  project.
         5)  Accurate measurements of actual  quantities of material used
             must usually be made for payment  purposes.  Most of the
             above duties must also be performed by  the on-site supervisor
             of force account  jobs who,  in  addition, must keep equipment
             maintenance records and  coordinate  all  labour on the
             project.
2.5.5    Type  of construction
         The two most  frequent methods of construction are contract and
force  account.  There can also be a combination  of the two on the same
project.

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                                  2-45
2.5.5.1  Force account.   Force  account  construction  is  where the funding
source hires  its  own  crews,  purchases its  own  materials and equipment,
and accomplishes  the  construction.
         The  following are  some of  the  advantages  of force account
construction:
         1)   It tends to  utilize  local  labour  or contractors to  a
              greater  extent.
         2)   It is usually  lower  in  cost.
         3)   Training of  the operators  and  users can take  place  during
              construction.
         4)   Equipment used  during  construction can  more easily  be left
              at the site  for operation  and  maintenance  of  the  completed
              facility.
         5)   It is easier (and  less  expensive) to  phase a  project or  make
              major changes  during construction should unforeseen
              difficulties arise.
         6)   Shorter  lead times are  usually possible for materials and
              equipment ordering.  (Contracts have  to be advertised,
              awarded, etc.,  and  the  successful bidder still must purchase
              his materials.)
         7)   There is more  flexibility  to  fit  into the  local environment
              and  social conditions.
2.5.5.2   Contract construction.  Contract  construction is where the
funding agency supplies plans and specifications and contracts with a
private firm  to accomplish  the  construction.  Advantages of this
contracting method are as follows:
         1)   There is usually more control  on  the  job,  and inspection
              is usually more thorough.
         2)   Completion times are sometimes shorter  because they are
              specified in the contract.
         3)  The owner or funding agency does not  take  as  high a risk and
             also does not need as large a work force on-site  (inspectors
             only).

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                                 2-46
         Some jobs will combined force account and contract.  For
instance, there are usually parts of a job for which the owner does not
have qualified crews to perform and he must contract those portions.
Large welded (on-site) steel storage tanks, erection of prefab metal
buildings, construction of sewage treatment plants, electrical work,
control and alarm systems and installation of piling are examples of
these specialities.
2.5.5.3  Construction techniques.  There are three main construction
techniques:  "stick built", "prefab", and "modular".   In stick built
construction the materials are shipped to the site, and all cutting and
fabricating is done on-site.  Prefab construction is where parts of a
structure, etc., are prefabricated at the point of manufacture and
assembled at the site.  Modular construction means large components are
constructed at the point of manufacture and shipped to the site already
constructed.
         Each technique can be useful under different  circumstances.
Modular construction has a definite advantage when there is a short
construction season, a labour shortage, or labour is expensive at the
site.  Shipping limitations may dictate stick built or possibly prefab
rather than modular construction.  Modular construction may allow the
facility to be placed in operation with most of the defects worked out at
the point of manufacture, but field changes to fit varying site
conditions are more difficult and expensive to make.
2.5.5.4  Above or below-ground.  The decision whether  to place utilities
above or below-ground must be made.  The major engineering consideration
is the soil conditions at the site.  Poor soil conditions (see Section
2.4.1) and lack of non-frost susceptible backfill will usually force
construction above-ground.  Otherwise below-ground installation is
preferable.  Important considerations are:
         1)  Above-ground lines are subject to vandalism and  traffic
             damage.
         2)  The allowable heat losses and the cost of energy (heat)
             required for above-ground lines must be assessed.

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                                 2-47
         3)  The necessity  of holding grades  with  above-ground gravity
             flow pipelines will  greatly  increase  the  cost.
         4)  Below-ground systems are less  expensive  to  install because
             they eliminate the need for  piles  and road  and  sidewalk
             crossings.
         5)  Below-ground systems allow for more normal  town planning and
             do not artificially  dissect  the  community.
         6)  More expensive equipment is  necessary to  maintain
             below-ground lines.
         Heat loss is directly proportional to  the difference between
the inside and outside  temperatures.  An  above-ground  utilidor or
pipeline will have about three times the  heat loss of  a  similiar line
buried just below the surface.
         If lines are buried, the depth of  bury should be  carefully
determined.  This will  be covered in detail in  Section 14.   Heat losses
from buried lines are considerably less but excavating frozen ground to
find and repair a leak, etc., can be difficult.  Also, a pipeline leak
can travel under the frozen surface layer and surface  through a ground
tension crack several feet  away.
2.6      Water Delivery and Waste Collection  Systems
2.6.1    Types of systems including construction,  operation, and
         maintenance costs
         The major types of water delivery  and  waste  collection systems
used in cold regions are discussed in the following paragraphs.  There are
many variations and alterations which can be  made  to  the basic types
presented here.  Detailed descriptions and  design  information will be
presented in later sections of this manual.
         Consideration  should be  given to phasing  facilities.  The first
phase could be a central watering point,  with a piped  or hauled system
following a few years later.  This would  lessen the economic and cultural
shock to the community  of the immediate installation  of  a  complete
system.
         Initial construction or  installation costs are  presented for the
different types of systems.  They are based on  1977 construction costs

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                                 2-48
and should be considered rough estimates only.  Actual costs can vary
considerably, depending on the sophistication of the facility,  the degree
of water and sewage treatment necessary, foundation problems and other
factors.
         Operation and maintenance (O&M) costs are also  presented  for  the
different types of sanitation facilities.  For most facilities, labour
costs are by far the most significant part of the O&M budget.   A military
site could be an exception because labour is covered under  "general
overhead".
         Two other large O&M costs are oil and electricity.  Both  of
these items are largely dependent on the delivered cost  of  oil.  If no
surface transportation is available it is necessary to fly  in  oil.  A
complicated water or sewer treatment process will make the  cost of
chemicals and their transportation a major O&M item.  The approximate  O&M
costs presented for each type of facility do not include amortization  of
the initial construction costs.  They do include funds to replace
short-lived components such as boilers, pumps, and vehicles (items with
less than 10 years design life).  Construction and O&M estimates are
summarized in Table 2-3.
2.6.1.1  Central watering point with individual haul of  water,  sewage,
and refuse.  This involves the development of a safe water  source  from
which individuals will haul their own water.  More than  one source may be
needed  in a larger community.  In some instances it may  be  feasible to
develop a source at each dwelling.  A self-haul system seldom  results  in
enough  water at the homes for adequate personal and household  sanitation.
         In some instances it is feasible to provide septic tanks, waste
bunkers, or privies at each dwelling.  In other cases users must be
responsible for delivering wastes to a central treatment and disposal
facility.  Treatment and disposal of the wastewater could consist  of a
lagoon  or treatment plant.  Refuse would usually be hauled  (by indivi-
duals to a landfill or fenced disposal site.
         Central watering points with individual hauling are lower  in
initial cost but provide the least health improvement and convenience
compared to other types of facilities.  Costs run  from $250 000 to

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TABLE 2-3.     COST OF WATER DISTRIBUTION AND SEWAGE COLLECTION FACILITIES IN COLD REGIONS (1977).

                                                          OPERATION AND
TYPE OF SERVICE               CONSTRUCTION COST        MAINTENANCE COSTS1            REMARKS
Individual-Haul
Vehicle-haul
$300 000
$500 000
$600/month
$70/month/house
Per facility
3
30 homes
Pipe Facilities                                                                                    3
(with minimimal fire          $35 000/house            $50/month/house               30 to 40 homes
protection)
                                                                       2                     3
Central Facility with         $900 000                 $140/month/house              60 homes
Individual-Haul
                                                                       2                     3
Central Facility with       $1 300 000                 $180/month/house              60 homes
Vehicle-Haul

i
 Amortization of initial construction costs is not included.   However, cost for replacing
 critical components  such as pumps, boilers,  vehicles, etc.,  is included.                                       i
2
 Approximately $30/ family/month can be recovered by using coin-operated showers, saunas, washers,
 and dryers.  Additional costs can be recovered if nearby facilities such as schools can be
 serviced directly.
3
 Five to six people/house.


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                                 2-50
$350 000 per facility.  The number of watering points needed  in  a  given
community will depend on how scattered the houses are, ground  conditions
throughout the community, possible water sources, and other factors.
         Individual-haul facilities also have the lowest O&M  costs  but
provide the least service.  Costs of $500 to $950 per month per  facility
are known.  The variance is primarily due to the sophistication  of  the
water and sewage treatment facilities needed.
2.6.1.2  Central watering point with vehicle delivery of water and
collection of sewage and refuse.  This involves the development  of  a  safe
water source from which a community or contractor will deliver water  to
storage containers in the users' buildings.  Sewage is collected from
holding tanks or in "honeybuckets", and delivered to a treatment/disposal
facility.  Refuse is also collected by vehicle and transported to  a
disposal point.  The sophistication of the plumbing within the individual
buildings can vary considerably, from individual pressure systems  with a
full complement of plumbing fixtures to an open container.
         Vehicle-haul facility costs will vary with the facilities
installed in the individual buildings, distance to the source/disposal
point, storage, and the truck fill point facility.  Initial installation
costs vary from $450 000 to $550 000.
         Operation and maintenance costs for vehicle-haul systems  will
depend on the above items plus the sizing of the building and  vehicle
storage and holding tanks.  The O&M costs run between $60 and  $80  per
house per month.  In northern Canadian communities, total costs  for
vehicle delivery and collection run between 1 and 2fc per litre,  but the
cost to the consumer is subsidized by the government.  Wheeled vehicles
seem to have a useful life of about four years in remote cold  regions and
tracked vehicles even less.  Vehicle-delivery systems are extremely
labour intensive (50 percent of total delivery cost), although this
usually provides several jobs in the community.
         A typical cost breakdown for a vehicle-delivery system  in  the
Northwest Territories is:  vehicle capital = 15 percent (four-year  life),
vehicle O&M = 21 percent, garage capital = 9 percent (10-year  life),  garage
O&M = 5 percent, and labour = 50 percent (@ $13 per hour for  two persons).

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                                 2-51
2.6.1.3  Central facility watering point with laundry and  shower
facilities.  A central  facility would provide water, laundering,  bathing,
and toilet facilities.  The fixtures and facilities are  usually coin-
operated.  "Honeybucket" wastes can also be deposited at the  facility  and
handled with the wastewater from  the facility.  More sophisticated
central facilities include incinerators for refuse disposal and treatment
of grey water for reuse.
         The initial costs for a  central facility with laundry, showers,
and water provided will depend primarily on the degree of  water treatment
necessary and the type  of sewage  treatment and refuse disposal  selected.
Either individual or vehicle-haul can be used in conjunction  with a
central facility.  A facility with individual-haul will  cost  from
$700 000 to $1 100 000  and serve  about 60 dwellings.  One  providing
vehicle-haul would cost between $1 000 000 and $1 600 000  depending,
again, on the degree of fixture sophistication within the  houses  (type of
tanks, flush toilets, etc.).  Central facilities which provide  bathing
and laundry facilities  would have to be financed and maintained by  the
homeowners who would have the other fixtures in their homes.
         The O&M costs  of a central facility would be $65  to  $80  per
family per month with individual-haul and $90 to $120 per  family  per
month with vehicle-haul.  A part  (approximately $30/family/month) of the
O&M costs for central facilities  can be recovered by using coin-operated
saunas, showers, washers, and dryers.  The remainder would have to  be
collected by billing the users and/or coin dispensing of water.   Some
costs can be offset by  providing water and sewer service to nearby
facilities such as schools and health clinics.
2.6.1.4  Complete piped water delivery and sewage collection.   Safe
water is distributed from the source to each building and  sewage  is
collected and transported to a treatment facility using  above or  below-
ground piped systems.   Refuse is  still collected by vehicle.  Piped water
systems may provide fire protection or domestic consumption only.   The
sewage collection system could be gravity, vacuum, or pressure  operated.
         Initial construction costs for complete piped facilities vary
greatly with the community layout and building density,  soil  conditions,

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                                 2-52
whether an above or below-ground system is used and other  factors.
Initial costs are higher than with the other alternatives  but  the
greatest health improvement and convenience is offered.
         Costs usually run between $30 000 and $40 000 per house, includ-
ing the cost of service lines but not house plumbing.  It  would  cost
another $2000 to add a sink, toilet and lavatory with the  proper plumbing
accessories to an existing house.  Piped facilities have lower O&M  costs
than vehicle-distribution and collection systems.  O&M costs  range  from
$40 to $65/family/month depending on the type of system used  (i.e., above
or below-ground, pipe or utilidor, gravity, or pressure or vacuum),
labour costs, compactness of area to be served, and degree of  treatment
needed.  These costs do not include heating water or the electricity  used
in the individual buildings for laundry and bathing.
2.6.2    Design life
         For the most part, the design life for facilities and equipment
in cold regions is shorter than for the same units operated in more
temperate climates.  This is especially true of equipment  which  must
operate outside in the winter.  The following list presents some commonly
used design lives for cold regions:
         Component;                             Design Life (years)
         Wells                                         30
         Pumps and controls                             5
         Boilers                                        5
         Storage tanks                                 40
         Water distribution lines                      40
         Meters                                        10
         Valves                                        10
         Septic tanks                                5 to  10
         Drainfields                                    5
         Sewage collection lines                       30
         Lift stations (not pumps)                     30
         Trucks                                         4
         Tracked Vehicles                            2 to  3
         Buildings                                     30

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                                 2-53
         Paint (outdoor)                               10
         Service connections                        10 to 15
         Backhoes (occasional use)                   6 to 10
         Compressors                                    5
2.7      Operation and Maintenance
2.7.1    Community and operator training
         Where the community operates its own system, successful  opera-
tion is very dependent upon the training and dedication of  people in  the
community, especially the operator.  The operator's dedication  and
acceptance of responsibility is a direct indication of how  successful and
how long the facility will operate well.  It is  usually easier  to ensure
proper operation for government-operated systems.  Training must  be
geared to the operator's education level.  In remote areas, experience
has shown that training carried out with the individual operator  at his
own plant is more successful (also, more expensive) than  bringing several
operators to a central location or educational institution  for  training.
Probably a combination of individual and group training is  desirable. At
least two operators should be trained for each facility to  allow  for
back-up when the main operator is not available.   Operator  training
should be provided in progressive levels, such as:
         Level 1 would provide basic emergency measures to  minimize
         facility damage (e.g. to drain the system or start standby pumps
         or boilers in case of a  failure of an important  part).  It would
         be desirable to have several people in  the community trained to
         this level.
         Level 2 would provide training for minor  repairs to  boilers,
         pumps, chlorinators, etc., to get them  back on line, in  addition
         to the Level 1 responsibilities.  This  level would not include
         much preventative maintenance, but would  provide primarily day
         to day operation.  Both  the main and standby operator  should
         have this level of training.
         Level 3 would include Level 1 and 2 training, and  preventative
         maintenance, such as keeping the boilers  in adjustment,  ete. The
         main operator should be  trained to this level at least.

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                                 2-54
         Level 4 would provide capable and interested Level 3  operators
         with training to a level where they would be able to  qualify  for
         formal certification as water and sewage treatment plant
         operators.
         First priority would be Level 1 training and then on  up  to
Level 4.  Most operators in remote native villages would not need  Level 4
training.  However, local laws or requirements may now, or in  the  future,
specify Level 4 training of all operators.  At construction camps  or
government installations it is probably desirable to train operators to
standards higher than those above because facilities are usually  more
sophisticated.
         Ideally, the operator and alternate operator should be  selected
at the beginning of construction so they can receive on-the-job  training
throughout construction.  The selection should be made  by the  community,
with technical help from the constructing or training agency,  because  the
community must accept and support the operators after they assume O&M
responsibilities for the facilities.  The operator should be selected  for
dedication and abilities, not because of political connections within  the
community.  Operator training is not a one-time responsibility;  it is
on-going.  Operators move on to better jobs, community  administration
changes and new operators are appointed, etc., making it necessary to
carry on a continuous training program.  The operators  must be paid
enough to keep them on the  job and to provide a comfortable living.
         Community education is also an important part  of the  training
process.  The community must realize the importance of  the operators and
support them morally as well as financially.  A community appreciation of
the health and convenience  benefits the facilities bring will  promote
this support.
         In a small community the operator may be responsible  for
collection of the user fees.  In large communities an administrative
staff handles collections,  and this should be considered  for any
community.  It will be more difficult for an operator to  hold  the
community's support if he is also shutting off their water for
non-payment of bills.

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                                 2-55
         The community administration or  the operator must  be  trained  in
bookkeeping, billing, employment  forms (tax withholding, workmen's
compensation, etc.), and  the other  functions needed  to  operate a utility.
The community must also pass and  administer ordinances  to  regulate  the
utilities.  Homeowners must often be trained in  the  correct use and care
of the new facilities installed in  their  homes.
         Whether or not O&M subsidies are  provided,  technical  and
management help must always be available  to the  operator and community.
         Occasional trips should  be made  to the  community  to meet with
the operator and discuss  any problems he may be  having  with his facili-
ties.  In cold regions it is important that one  of these visits be  made
in the fall so any problems or repairs that need  to  be  made can be
done before winter, especially those that  would  jeopardize  the integrity
of the system.  On these  visits,  all critical  components should be
inspected to make sure they (and  their standby units) are  operating
properly.  Another visit  should be  during  the  summer when  all  lines can
be flushed and fire hydrants operated and  cleaned.
2.7.2    Operation and maintenance manuals
         Operation and maintenance  manuals are extremely important  if  the
operator is to correctly  care for his facilities  [25],  They should be
written during construction so that they are available  for  system start-
up.  They should include  many pictures of  all  components discussed.
Arrows can indicate exactly what  part is being discussed.   They must also
be written for the individual operator's education level and include:
         1)  accurate and complete  as-built drawings (layout of system,
             piping, diagrams, etc.);
         2)  complete parts list  and suppliers'  names and  addresses for
             all equipment, chemicals, etc., that must  be  maintained;
         3)  step-by-step troubleshooting  lists  of all  possible problems;
         4)  step-by-step repair  and maintenance  lists  for  all equipment
             and parts;
         5)  a good index so the  operator  can  quickly find  the items he
             needs;

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                                 2-56
         6)  the names and phone numbers of people the operator can call
             day or night in case of an emergency that he is unable to
             handle without help;
         7)  a definition of each part of the facility, what its  function
             is, and why it is important.
2.7.3    Reliability
         The reliability of utility systems depends mainly on  the quality
and quantity of the preventative maintenance performed by the  operator.
Reliability is important because of the expense involved in replacement
or repair in remote areas in cold regions, and because of the  consequences
of catastrophic failure of the entire facility because of the  failure of
an inexpensive control.  Reliability must be a major consideration in
selecting components and equipment.  This includes the availability of
repair parts and service.
         Because of the unreliability of power in cold regions, standby
generation capability must be provided for all critical components of a
facility.
         A facility that is less automated and, therefore, needs  more
operator attention will be very  reliable if the operator is competent.
However, if he is not, a facility which is automated to a high degree
will prove more useful, in spite of the tendency for sophisticated
equipment to malfunction.
2.7.4    Management backup
         In addition to training operators and making occasional  visits,
a responsive backup system to help operators solve problems is essential.
This support involves helping the operator get parts he needs, helping
the bookkeeper work out problems, being readily available to help the
operators with technical advice  and working out complex problems  on-site,
responding with qualified people and materials during emergencies, and
making regularly scheduled visits several times a year to help the
operators maintain a sound preventive maintenance program.

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                                  2-57
 2.8       References

 1.    Ryan,  William L.,  "Design and  Construction  of  Practical  Sanitation
      Facilities  for Small  Alaskan Communities".   Permafrost:   The North
      American  Contribution to  the Second  International  Conference,
      National  Academy  of Sciences,  Washington, D.C.,  1973.

 2.    U.S. Public Health Service Monograph No.  54-1958.   PHS  Publication
      No.  591,  U.S.  Government  Printing  Office, Washington, D.C.,  1958.

 3.    Associated  Engineering  Services, Ltd.,  "Wabasca  -  Desmarais, Water
      and  Sanitation Feasibility Study", prepared  for  the  Northern
      Development Group, Alberta Executive Council,  Government  of  the
      Province  of Alberta,  1974.

 4.    Gamble, D.J.,  "Unlocking  the Utilidor", Proceedings  of  the Symposium
      on Utilities Delivery in  Arctic Regions,  Environmental  Protection
      Service,  Environment  Canada, January,  1977  (Report No.  EPS 3-WP-77-1).

 5.    Puchtler, Bert, "Water-Related Utilities  for Small Communities in
      Rural  Alaska",  Report to  Congress  authorized by  Section  113  Public
      Law  92-500,  U.S.   Environmental Protection Agency, Washington, D.C.,
      1976.

 6.    Muller, Siemon  William, Permafrost or  Permanently Frozen  Ground, and
      Related Engineering Problems, J.W. Edwards,  Inc., Ann Arbor,
      Michigan, 1947.

 7.    Buvert, V.V.  et al, "Snow and  Ice  as Materials for Road Construction",
      translation  #  54, U.S. Army Corps  of Engineers,  (CRREL),  1957.

 8.    Tomayko, D.J.,  "Elevated  Snow Roads  in Antarctica",  The Military
      Engineer, No.  429, January - February, 1974.

 9.    Clark, E.,  et  al, "Expedient Snow  Airstrip Construction Technique",
      U.S. Army Corps of Engineers, Cold Regions Research  and Engineering
      Laboratory  Special Report # 198, 1973.

 10.   Hansen, B.L., "Instruments for Temperature Measurements in Perma-
      frost", Proceedings of the First International Permafrost Conference,
      Purdue, 1963.

 11.   Crory, F.E., "Pile Foundations in Permafrost" Proceedings of the
     First International Permafrost Conference, Purdue, 1963.

12.  Penner, E.,   "Frost Heaving in Soils", Proceedings of the First
     International Permafrost Conference.  Purdue, 1963.

13.  Berg, R.,  "The Use of Thermal Insulating Materials in Highway
     Construction in U.S.", U.S. Army Corps of Engineers, Cold Regions
     Research and Engineering Laboratory,  Report  # MP 539, 1974.

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                                 2-58
14.  Smith, D.W. and Justice, S.R.,  "Clearing Alaskan Water Supply
     Impoundments.  Management Laboratory Study and Literature Review",
     Institute of Water Resources,  Report No. IWR-67, University of
     Alaska, Fairbanks, 1976.

15.  Carlson, A.R.,  "Heat loss and  Condensation in Northern Residential
     Construction",  and "Design of  Floors for Arctic Shelters",
     Proceedings of  Symposium on Cold Regions Engineering, University of
     Alaska, College, Alaska, 1971.

16.  Floyd, P., "The North Slope Center:  How Was It Built?", The
     Northern Engineer, Vol. 6, No.  3., 1974.

17.  Tobiassion, W., "Deterioration of Structures in Cold Regions",
     Proceedings of  the Symposium on Cold Regions Engineering, University
     of Alaska, College, Alaska, 1971.

18.  ASHRAE Handbook of Fundamentals (latest edition), American Society
     of Heating, Refrigerating, and Air Conditioning Engineers, Inc.

19.  Pritchard, G.B., "Foundations  in Permafrost Areas", Proceedings of
     the First International Permafrost Conference, Purdue, 1963.

20.  Tobiasson, W.,  "Performance of the Thule Hanger Soil Cooling
     System", Proceedings of the Second International Permafrost
     Conference, Yakutsk, USSR, 1973.

21.  Miller, J.M., "Pile Foundations in Thermally Fragile Frozen Soils",
     Proceedings of  the Symposium on Cold Regions Engineering, University
     of Alaska, College, Alaska, 1971.

22.  Seeding Recommendations for Revegetation of Arctic and Subarctic
     Soils, personal discussions with U.S. Dept. of Agriculture, Soil
     Conservation Service, Anchorage, Alaska; Institue of Agriculture,
     University of Alaska, Palmer,  Alaska; and Alaska State Division of
     Aviation, Anchorage, Alaska, 1974.

23.  Hamelin, L.E.,  "A Zonal System of Allowances for Northern Workers",
     MUSK-OX, Publication 10, 1972.

24.  Gordan, R., "Batch Disinfection of Treated Wastewater with Chlorine
     at Less than 1C.", U.S. EPA # 660/2-73-005, September 1973.

25.  Squires, A.D.,  "Preparation of an Operations and Maintenance
     Manual", In Symposium on Utilities Delivery in Arctic Regions,
     Proceedings published as Environmental Protection Service Report No.
     EPS 3-WP-77-1,  Environment Canada, January, 1977.

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                                 2-59
2.9      Bibliography

     Alaska Department of Commerce and Economic Development, Directory of
     Permits, Juneau, Alaska, 1978.

     Christensen, Vern, and Reid, John, "N.W.T. Water and Sanitation
     Policy and Program Review", Department of Planning and program
     Evaluation, N.W.T., Canada, December, 1976.

     Cooper, I.A., and Rezels, J.W., "Vacuum Sewer Technology", prepared
     for the U.S. EPA Technology Transfer Seminar Program on Small
     Wastewater Treatment Systems, 1977.

     Grainge, J.E., and Shaw, J.W., "Community Planning for Satisfactory
     Sewage Disposal in Permafrost Regions", paper presented at Second
     International Symposium on Circumpolar Health, 1972.

     Grainge, J.W., "Study of Environmental Engineering in Greenland and
     Iceland", Canadian Division of Public Health Engineering, Department
     of Health and Welfare, Report No. NR-69-5, 1969.

     Heinke, G.W., "Report on Environmental Engineering in Greenland and
     Northern Scandinavia", Dept. of Civil Engineering, University of
     Toronto, October, 1973.

     Kreissl, J.F., "Status of Pressure Sewer Technology", prepared for
     the U.S. EPA Technology Transfer Design Seminar for Small Flows,
     1977.

     Simonen, E., and Heinke G., "An Evaluation of Municipal Services in
     the Mackenzie River Delta Communities", Publication No. 70-60 Dept.
     of Civil Engineering, University of Toronto, 1970.

     Tsytovich, N.A., The Mechanics of Frozen Ground, McGraw-Hill and
     Scripta Book Company, New York, 1975.

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                                 SECTION 3
                        WATER  SOURCE  DEVELOPMENT
                                   Index
                                                                     Page
3        WATER SOURCE DEVELOPMENT                                    3-1
3.1      General                                                     3-1
3.2      Water Sources                                               3-3
3.2.1    Surface water                                               3-3
3.2.2    Groundwater                                                 3-6
3.2.3    Other water sources                                         3-9
3.3      Water Requirements                                          3-10
3.3.1    Water usage                                                 3-10
3.3.2    Demand factors                                              3-14
3.3.3    Fire flows                                                  3-15
3.3.4    Water quality                                               3-15
3.4      Structures                                                  3-18
3.4.1    River intakes                                               3-18
3.4.2    Infiltration galleries                                      3-22
3.4.3    Wells                                                       3-26
3.4.4    Pumping stations                                            3-28
3.4.5    Transmission lines                                          3-31
3.5      References                                                  3-31
3.6      Bibliography                                                3-32

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                             List of Figures
Figure                                                              Page
 3-1     Hydrograph of Mean Daily Discharge, Kuparuk River          3-4
 3-2     Computer Simulation of the Effect of a River on
         Permafrost                                                 3-8
 3-3     Hourly Peak Water Demand in Small Cold Climate
         Communities                                                3-15
 3-4     Water Quality in Upper Isatkoak Lagoon, Barrow,
         Alaska, 1975-1978                                          3-19
 3-5     Water Truck Filling at Water Lake at Cambridge Bay, NWT    3-20
 3-6     Water Intake at Fort MePherson                             3-20
 3-7     Intake House in Peel Channel at Aklavik                    3-20
 3-8     Piping Schematic for Water Intake                          3-21
 3-9     Water Intake Schematic                                     3-23
 3-10    Supply Utilidor at Coppermine, NWT                         3-24
 3-11    Infiltration Galleries                                     3-25
 3-12    Well Seal                                                  3-29
 3-13    Pumphouse at Williamson Lake in Rankin Inlet, NWT          3-30
 3-14    Pump Station                                               3-30
                             List of Tables
Table                                                               Page
 3-1     Recommended Water Usage                                    3-12
 3-2     Examples of Actual Water Use                               3-13
 3-3     Fire Flow, Fire Reserve and Hydrant Spacing Recommended
         by the National Board of Fire Underwriters                 3-16

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                                   3-1
3        WATER  SOURCE  DEVELOPMENT
3.1      General
         Cold climate  conditions require  special  attention when selecting
and developing  water sources.  Hydrologic  conditions  in northern latitudes
differ from those  in sourthem regions  in  several important respects.
This is true of both groundwater and  surface  water in areas of continuous
permafrost.  Throughout much  of the cold  region of North America,  precipi-
tation is light, terrain in populated regions is  relatively flat,  and
yearly runoff is concentrated in the  short  period during ice breakup.
There are many  small,  shallow lakes and ponds and numerous rivers  and
creeks.  Ice cover varies  according to  local  conditions, but generally
lasts from six  to  10 months.  Hydrologic  data on  northern lakes, streams
and groundwater are scarce and typically  cover periods of short duration.
This makes it difficult to predict reliable yields for water supply
purposes.
         Permafrost is impermeable for  all  practical  purposes.  Runoff
from melting and precipitation tends  to occur in  a shorter period  and  is
more complete than in  areas without permafrost.   This phenomenon also
greatly reduces the recharge  of aquifers.  Any construction in permafrost
regions requires special consideration  and unique engineering, particularly
in regard to cost  and  the  technical problems  of maintaining water  flow.
Often, permafrost  conditions  prevent  the  application  of standard techni-
ques and preclude  the  development of  available groundwater sources. The
costs of developing, maintaining, and operating a water source in  cold
climates are greater in all respects  than  in  temperate regions.  Costs
will vary with  each location; however,  they generally increase with
decreasing mean annual temperature and  remoteness of  the site.
         Regardless of the apparent merits of a source under consideration,
there is no substitute for detailed preliminary engineering studies and
direct observation of  local conditions  prior  to final selection.  Some
type of water source may be developed in  virtually any part of the cold
region of North America, but  the physical  difficulty  of operation  and
maintenance or  the associated costs may be highly unattractive.

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                                  3-2
         The governments of both the United States and Canada support  the
collection and publication of basic data of value in planning water
supply systems.
         The Canadian Department of Environment publishes an annual
report entitled "Surface Water Data - Yukon and Northwest Territories",
which lists stream flows at selected stations in the Northwest
Territories.  This publication is prepared by:
         Inland Waters Directorate
         Water Survey of Canada
         Environment Canada
         Ottawa, Ontario K1A OE7
The annual U.S. Government publication, "Water Resources Data for
Alaska", includes information on stream flows and water quality for
selected streams.  This publication is available from:
         U.S. Geological Survey
         District Chief, Water Resources Division
         218 "E" Street
         Anchorage, Alaska 99501
         In addition to these publications, special reports may be
available from the U.S. Geological Survey agency on particular locations
dealing with short-term data, groundwater, or special water quality
studies.  Both nations maintain agencies concerned with weather and  other
climatological factors which regularly publish their data.  One example
is "Ice Thickness Data for Canadian Selected Stations".  Precipitation is
also recorded and published.  For this information the following offices
should be contacted:
         Atmospheric Environment Service
         Environment Canada
         Ottawa, Ontario K1A OH3
         National Weather Service Forecast Office
         632 6th Avenue
         Anchorage, Alaska 99501

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                                   3-3
3.2      Water  Sources
         Water  in cold  regions  comes from the same basic sources as in
temperate  areas,  but  there  are  some peculiarities to arctic and subarctic
surface and  groundwater hydrology which merit comment.
3.2.1    Surface  water
         Surface  water  results  from precipitation and snowmelt and is
replenished  through  the hydrologic cycle.  In northern latitudes surface
waters in  shallow lakes and small streams may be effectively eliminated
in the winter because of complete freezing.   Larger streams and deep
lakes may  remain  liquid beneath an ice  cover but flows and volumes are
reduced since there  is  no contribution  from  precipitation until warm
weather returns.   In  some cases,  pressure between the stream bed and
downward-growing  ice  cover  forces flows to the surface through cracks and
along the  shores  where  it then  freezes.  Frozen water of this type is
called "aufeis" and  is  essentially not  available until breakup and thaw
occur.  This has  a smoothing effect on  the runoff hydrograph by reducing
the peak and increasing the flow during the  melt.  Large snow drifts also
contribute to runoff  in this manner.  Thus,  it becomes apparent that
because of the  cold  climate and quantity of  ice, not all surface sources
are available for continuous water supply.  Sources which are suitable
for continuous  supply are large rivers  and large lakes.   Figure 3-1 shows
a hydrograph for  a typical  medium-sized arctic river.
3.2.1.1  Rivers.   Rivers are an excellent water source in winter
because sediment  transport  is minimal and overland flows, which tend to
lower water quality, do not occur.   The disadvantages of rivers as a
supply source include low water temperatures  and flowing ice during
freeze-up and break-up  periods,  which may damage or destroy water intake
structures.  Also, in alluvial  streams  it is  difficult to locate a
permanent channel  beneath the winter ice.
         Summer river flows,  which tend to be  much higher,  frequently
contain sediments  or glacial flour from overland runoff  or  melting
glaciers which  cause difficult  treatment  problems.
3.2.1.2  Lakes.   Lakes  may  be a good continuous source of water,
depending upon  the size (area and depth)  and  the severity of the climate.

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   100,000
 CO

co"
 o>
 O)
 CO
 _c
 ,o
 CO
 "CO
 "D

 c=
 CO
 CD
     10,000
1000
       100
                                              1970

                                              1971
                                                                                            10.0
                                                                                      1.0
                                                                                           _CD

                                                                                           1
                                                                                           X
                                                                                           CO
                                                                                           O
                                                                                           c
                                                                                           13
                                                                                                          U)
                                                                                                          I
                                                                                            0.1
                     June
                                   July
August
September
                  FIGURE 3-1.  HYDROGRAPH  OF  MEAN DAILY DISCHARGE, KUPARUK RIVER

                               (Data Source:   U.S. Geological Survey).

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                                   3-5
          Shallow lakes may freeze to the bottom in arctic regions or may
 freeze-concentrate impurities below the ice to the extent that the water
 is no longer of acceptable quality.  Ice formation is proportional to the
 air temperature.  A general expression of this phenomenon is called
 Steffan's equation:
                 /2k~l7                                         (3-D
            A -  ;	
                V  L
 in which:  X = ice thickness,
           If = freezing index,
            L = volumetric heat of fusion of water,
            k = thermal conductivity of ice (see Section 15).
          Impurities,  such as  most salts, are rejected from the freezing
 water, making the ice relatively pure.   The more slowly ice is formed,
 the more  efficient this process becomes.  The net effect of this pheno-
 menon is  that impurities become concentrated in the water beneath the
 ice.   It  may be generalized that if the liquid content of a lake or pond
 is reduced  50 percent by ice  formation, dissolved salt concentrations
 will  double.   Careful thermal and chemical  analyses are required to
 identify  a  lake or pond which may freeze deep enough to create this
 condition.   (For details see  Section 15.)
 3.2.1.3   Watershed yield and  quality improvement.   The amount of water
 yielded by  a  given watershed  is related to  the precipitation received by
 the watershed.   Other factors which influence yield are evaporation to
 the atmosphere  and transpiration by vegetation.
          To  estimate  runoff or yield,  records  of  the  precipitation,
 evaporation  and  temperature are needed.   The  agencies listed in  Section
 3.1 maintain  current  data  for many  locations.   Some agencies,  such as the
 U.S.  Geological  Survey,  calculate and  publish  watershed  yields for
 specific  stream  locations.  When  no  other  information is  available these
data  should be  used as  a guide.   For  large  projects where  accurate
information  is  critical, data  should  be  collected  for several  years  prior
to final  design  to  assure  that  the  required  yield  will,  in fact,  be
available.

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                                  3-6
         In cold regions, particularly in  the Arctic, most  precipitation
is in the form of snow.  However, due to winds it does  not  necessarily
remain where it fell initially.  This fact has been  used  to increase  the
annual water yield of small watersheds by  inducing  the  occurrence  and
growth of snow drifts.  Near Barrow, Alaska  the U.S.  Army augmented  the
fresh water supply by using snow fences.   This work  provided  valuable
information for evaluating the technique.  Accumulation of  at least  10.1
 o
mj of water for every metre of 1.5-metre high snow  fence  is possible.
The cost of this water (in 1975) indicated that over  a  10-year amortiza-
tion period for snow fences, 0.2 m^ of water could  be produced annually
for about one penny [1].
         In some areas it may be more economical to  develop only an
intermittant source and depend upon artificial storage  for  periods when
the natural supply is low, e.g., when all  surface water freezes during
the winter, or during periods of highly turbid river  water.
3.2.2    Groundwater
         Groundwater may be considered the most desirable source of  water
in cold regions for several reasons.  Normally, groundwater temperature
in the winter is warmer than surface water and is nearly  constant
year-round.  Mineral quality of groundwater  is more  constant  than  surface
water.  Also, subpermafrost groundwater is almost always  a  year-round
source of supply, so that alternate or dual  source  systems  need not  be
developed.
         The cost of exploring, drilling, developing  and  maintaining
wells in cold remote areas can be high.
3.2.2.1  Groundwater in permafrost.  Groundwater in  areas of  continuous
permafrost may be found in three general locations:   1) above permafrost,
within the active layer (suprapermafrost); 2) within  permafrost in thawed
areas (intrapermafrost); and 3) beneath permafrost  (subpermafrost).
         Waters found in the active layer  above the  permafrost are
generally unsuited for potable water supplies without extensive treat-
ment.  Such water is usually found within  three to  eight  metres of the
surface and frequently has a high mineral  content.   Because they are
shallow, such aquifers are also subject to contamination  from privies and

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                                   3-7
septic  tanks.   The  quantity of  this  water  source is often low and
unreliable.  A system for  use of  suprapermafrost water  was developed for
Port Hope, Alaska  [2].
          Intrapermafrost water  is quite  rare  and usually very highly
mineralized.   Such  water must contain  high concentrations of impurities
which depress  the  freezing point  below that of  the  surrounding perma-
frost.   There  is no reliable method  to locate pockets of intrapermafrost
water with present  state-of-the-art  techniques.   For these reasons it is
not normally a suitable water source.
          Subpermafrost groundwater is  the  most  reliable and satisfactory
groundwater source  in permafrost  regions.   Recharge of  subpermafrost
aquifers  occurs beneath large rivers and lakes  where there is no
permafrost.  In general, when fine-grained soils are frozen the movement
of groundwater is effectively prevented.   Satisfactory  wells have been
located  near rivers or large lakes since the  ground in  these areas may
not freeze.
          Subpermafrost groundwater is  generally  deficient in dissolved
oxygen.   As a  result, high concentrations  of  some salts, such as  those of
iron and  manganese  which may readily dissolve under these conditions,  are
present.  Hardness  is also  common in subpermafrost  groundwater.
Occasionally groundwater will contain  dissolved  organic materials in
addition  to hardness, iron and  other minerals.
          Costs  for  drilling  and well maintenance are higher in permafrost
areas.   The water must be  protected  from the  cold permafrost and  the
permafrost needs to  be shielded from the heat of the water.   This often
requires  special well castings, grouting methods and heat-tracing water
lines, all contributing to  increased cost.
          A computer  simulation  of the  effect  of  a meandering river on
permafrost has been  developed [3].   Figure 3-2 shows a  typical example of
this type of calculation.   The  application  of this  information is greater
for groundwater development  than  for surface  water.  A  well  might
conceivably be located where it would  penetrate  an  aquifer  being
continuously recharged by  a  river.
3.2.2.2   Estimation  of groundwater yield.   The predictable  yield  of
groundwater from a  watershed may  be  estimated in a  manner  similar to  that

-------
Depth (metres)
Depth(metres)
Depth(metres)
                           CD
                                                                                        00
                                                                                        o
                                               O)
                                               o
                                                                             CD
                                                                                                                              CD
                                                                                                                              Ol
                                                                                                                              IV)
                                                                                                                              o
                                                                                                                              o
                                                                                                                        CD
                                                                                                                              o
                                                                                                                              o
                                                                                                                                u>

                                                                                                                                CO
                                                                                                                              05
                                                                                                                              o
                                                                                                                              o
                                                                                                                       CD
                                                   01
                                                   o
                                                   CD
                                                   O)
                                                  to
                                                  o
                                                                                                       en
                                                                                                       o
                                                                                                       CD
                                                                                                       (D
                                                                                                      (Q
                                                                                                       o

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                                      3-9
for estimating surface runoff.  The concept involves balancing all inputs
with the withdrawals.  In practice, however, measuring the inputs and
withdrawals may be quite complex.
     The safe groundwater yield (Y ) is equal to the watershed
                                  o
precipitation (P), less surface flow out of the watershed (Q ), less
                                                            s
evapotranspiration (E) plus the net groundwater inflow (Q ), less the
                                                         o
net change in surface storage  (AS), less the net change in groundwater
storage (AG).
Thus,
               Y  =P-Qs-E+Q  -AS-AG               (3-2)
Only two terms in the above equation can be measured with reasonable
accuracy, P and Q ; the others must be estimated.  Recharge of
                 s
aquifiers in permafrost regions is much more limited than in other areas
because permafrost may be an impermeable barrier.  Hydrologists experienced
in cold region work should be  consulted when estimates must be accurate.
3.2.3     Other water sources
          Snow, ice, and direct catchment of rainfall are potential water
sources which may be considered for small or temporary establishments.
3.2.3.1   Snow and ice.  In general, the natural quality of these
sources is high but contamination of the ice or snow stockpile is a real
hazard.  Also, the cost of melting is significant and there are added
costs for harvesting and storing equipment and melters.  If significant
quantities of waste heat are available (e.g. from a nearby power plant),
this method may be more attractive.
     Induced snow drifting may improve the feasibility of using snow
as a source of water.  However, unless the need is temporary and the
population to be served is small, direct melting will not be practical.
Large volumes of snow are required to obtain even small quantities of
water and the cost of snow melting is high.   It has been estimated that
approximately one litre of "Arctic" diesel is required to produce 70
litres of water from snow [4].  In addition to fuel cost, labour for
operating snow melters and snow harvest equipment must be considered.
     Slaughter et al. [1]  concluded that parallel snow fences  spaced
50 to 100 meters apart would trap a maximum amount of snow.   Fences
should be erected so that they concentrate drifts near stream channels to

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                                 3-10
assure a better runoff  and  easier collection.   Fences  between  1.5 and
3.6 metres high have been used  in various  configurations.   Each installa-
tion should be designed  to  fit  the local situation.
3.2.3.2  Seawater and brackish  water.  Desalinated  seawater has been
used for domestic supply but  the associated  problems are considerable.
Intakes in the ocean or on  the  beach are subject  to ice  forces  of pheno-
menal magnitude.  Ice scour of  beaches at  all  times during  the  year must
be considered because of combinations of wind  and  sea  ice.   During the
winter months, shore-fast ice and frozen beaches  pose  special  problems.
The largest drawback is that  there are no  economical (from  an  operating
and management standpoint) methods to desalinate  seawater on the scale
necessary for a small community or camp.
         Brackish water with  total dissolved solids (IDS) of <  10 000
mg/L is occasionally the only source available.   Such  waters may be
treated by reverse osmosis or distillation but  significant  problems must
be anticipated at small installations.
3.2.3.3  Water reuse.   In the absence of ample  supplies of  fresh water,
water reuse may be considered.  In Alaska, bath and laundry water are
reclaimed and reused at several locations  for  toilet flushing and other
non-potable purposes (see Section 11 for more  details).  Regeneration of
potable waters is not yet state-of-the-art technology  but it is logical
to work toward that end in areas of extreme water  shortage.  Seawater
contains approximately  35 times more dissolved  solids  than  domestic
sewage.  The effluent from existing secondary  or  tertiary sewage treat-
ment plants is basically free from suspended materials and  should be more
economical to treat than seawater [5],
3.3      Water Requirements
3.3.1    Water usage
         The amount of water used by inhabitants of northern communities
depends on several factors.  Cultural background  is particularly impor-
tant since many cold climate communities are populated by Indians and
Eskimos.  Traditionally, native people have not had access  to large quan-
tities of water and as a result they tend  to use water conservatively.
However, as water becomes available, it is used more freely.  In construe-

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                                  3-11
 tion  camps, workers  may  use  large  quantities  of  water  but  this,  too,
 depends on  the  nature  of the  camp.   Residents of temporary camps use  less
 water  than  in base camp  situations.   Availability (or  installation) of
 plumbing  fixtures is another  factor  which  influences use,  perhaps more
 than  any  other  factor.
          The minimum amount  of  water considered  adequate  for drinking,
 cooking,  bathing and laundry  is 60 L per person  per day.   Even  this may
 be difficult to achieve  where piped  delivery  is  not practical or possible.
 Current experience indicates  that  in communities without  residential
 pressure  systems which have  "honeybag" waste  systems water consumption is
 approximately 4 to 12 L/person/d.
          Analysis of three years of  data collected at  Wainwright, Alaska,
 indicated that water use in homes  rose from about  2 L/person/d  in January
 1974,  to  about 5.5 L/person/d in December  of  1976  and  the  upward trend
 appears to be continuing.  Wainwright, however,  has a  central facility
 which  provides  for bathing and  laundry away from the home  which  was not
 included  in these figures.   In  spite of these apparently low quantities
 for household use, significant  health benefits have been observed in  the
 village from improved water quality  and sanitation facilities.
          Table 3-1 presents water  use factors for various  types  of
 communities in cold  regions.
         Water conservation.  Even though  these  recommended  quantities
 are recognized as adequate, many communities  in  Alaska and Canada consume
 large  quantities of  water which are  essentially  wasted.  Table 3-2 gives
 examples  of water use showing excessive quantities in many cases.
          System designers must  be alert to the possibilities  for conserv-
 ing water and potential  reasons why  systems sometimes encourage  waste.
Water  and its treatment  costs money,  as do sewers and  sewage  treatment
which must handle the hydraulic loads.  Appendix B summarizes the various
household water conservation  fixtures, including toilet systems.
         Bleeding.   Users must  be discouraged  from allowing water to  run
 to prevent freeze-up of  service lines.  This  type of wastage  is  most
common in the spring when frost penetration is greatest.   To  compound  the
problem, water sources are lowest in  early spring.  Subarctic cities  seem
to be more prone to  this situation,  probably  because service  lines in  the

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                                     3-12

                      TABLE 3-1,  RECOMMENDED WATER USAGE
                                                         Litres/person/day
Households                                             Average   Normal Range

1.  Self-haul from watering point                        <10       5-25

2.  Truck System
    a) non-pressure water tank, bucket toilet and         10       5-25
       central facilities
    b) non-pressure water tank, bucket toilets, and       25      10 - 50
       no central facilities
    c) non-pressure water tank, waste holding tank        40      20 - 70
    d) pressure water system, waste holding tank and      90      40 - 250
       normal flush toilet*
3.  Piped System** (gravity sewers)                      225     100 - 400
4.  Piped System (vacuum or pressure sewers)             145      60 - 250
5.  Well and Septic Tank and Tilefield                   160      80 - 250

Institutions (piped system)

School:  day student                                     10        2-18
         boarder                                        200      100 - 400

Nursing Station or Hospital:  per bed                   100

Hotels:  per bed                                        100

Restaurants, Bars:  per customer                          5

Offices:                                                 10

Central Facilities:
     Showers (2 per person/week)                         10
     Laundry (2 loads/family/week)                        7

Work Camps

Base Camp                                               200

Drilling pad                                            130

Temporary, short duration camps                         100
*    Conventional flush toilets not to be permitted with truck system  in  future.

**   xhe  figures for piped  systems do not make allowances  for the practice of
     letting  fixtures remain open in cold weather to provide continuous flow
     in watermains to prevent freezing.  Water use under that practice used
     only in  older systems  may be as high as several thousand litres per
     person per day.

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                                 3-13
                   TABLE 3-2.  EXAMPLES OF ACTUAL WATER USE
City
Minto, Ak.

Anchorage, Ak.

Unalakleet, Ak.
Dot Lake, Ak.

Homer , Ak .

Seward, Ak.


Bethel, Ak.

Dillinghara, Ak.

Seldovia, Ak.
Kenai, Ak.
Palmer , Ak .
Fairbanks , Ak .

Clinton Creek, Y.T.

Dawson City, Y.T.

Mayo, Y.T.

Whitehorse, Y.T.

Faro, Y.T.

Inuvik, NWT (1976)

Inuvik, NWT (1970)
Resolute Bay, NWT
Resolute Bay, NWT (1970)
Yellowknife, NWT
Yellowknife, NWT
Aklavik, NWT
Fort McPherson, NWT
Edmonton, Alberta

Litres/
person/
day
190

890*

300
190

1630*

4500**

2300**
270

2300*

680*
380
760*
650*

1140*

6400**

1700*

1680*

1140*

485-550

20
163
23
485
90
63
250
236

Approx.
number of
people
180

120 000

400
50






1 200






25 000

381

745

462

11 217



3 500

1 300

160
10 000

600
850
500 000

Type of System
Circulating water - gravity
sewers
Conventional water and
gravity sewers
same as Minto
Central heat - conventional
water, individual sewer
Conventional water and
gravity sewers
Conventional water and
gravity sewers (winter)
(summer)
Circulating water and gravity
pressure sewer
Conventional water and gravity
sewer
same as Dillingham, Ak.
same as Dillingham, Ak.
same as Dillingham, Ak.
Circulating water and gravity
sewer
Circulating water and gravity
sewer
Circulating water and gravity
sewer
Circulating water and gravity
sewer
Circulating water and gravity
sewer
Circulating water and gravity
sewer
Circulating water and gravity
sewer
Trucked water, honeybags
Circulating water
Trucked water, honeybags
Piped water, gravity sewer
Trucked water, sewage pumpout
Summer piped system
Piped portion of community
Conventional, residential
only

*  some water wasting




** indicates leakage in old water pipes

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                                     3-14
Arctic are better designed for low temperatures and are usually heated or
recirculated.  Four remedies for this problem are to:
          1)  educate water users,
          2)  meter all customers (services),
          3)  provide inexpensive and quick methods of thawing
              frozen service lines,
          4)  construct service lines that are less apt to freeze.
Item 4) is the most important; keys  to its accomplishment are:
          a)  bury lines below frost line until within the thaw bulb of
              the house,
          b)  insulate lines if there is a possibility of the surrounding
              ground freezing,
          c)  recirculate the water  in service lines,
          d)  provide heat tapes on  lines in frost zone,
          e)  add heat to water in distribution system.
          Leakage.  A lot of water is wasted because of leakage from old
or broken service lines and mains and because of poorly maintained plumb-
ing within buildings.  Possible methods of minimizing losses of this kind
are to:
          1)  maintain pressure in mains at the lowest pressure
              necessary (about 25 psi, 172.5 k Pa),
          2)  promptly repair all leaks in mains and service lines,
          3)  check system for leaks frequently by isolating sections and
              pressure testing,
          4)  educate users on the causes of each and train them to repair
              leaking fixtures such  as faucets and toilets.
3.3.2     Demand factors
          Factors used for computation of peak demand in small systems in
cold regions will be somewhat higher than in temperate regions and for
larger communities.
          Maximum daily demand should be computed at 230% of the average
daily demand.  Maximum hourly demand should be computed at 450% of the
annual average daily demand.

-------
                                  3-15
         Figure 3-3  is  presented for estimating hourly peak water  demand
in small cold climate communities.
           o
           CD
           in
           ~O
           tz
           ro
           E
           CD
           T3
           ^
           CO
           CD
           Q_
                       Above 50 dwelling units
                       Demand = [7 9 + 0076(N-50)]
                       Where N = No  of dwelling units
                       Demand = Peak flow in litres/sec
                              40      60      80
                            Number of dwelling units
                                          100
120
 FIGURE 3-3.  HOURLY  PEAK WATER DEMAND IN SMALL COLD CLIMATE  COMMUNITIES
3.3.3
Fire flows
         In larger  towns  and cities water available for the fire  flows
should meet requirements  of the National Board of Fire Underwriters  (see
Table 3-3).   In  smaller northern communities this is not feasible  because
of the distribution system such flows require.  Because of the  overall
demand where  only marginal sources of potable water exist, separate  systems
may be considered which would use untreated water such as seawater or river
water in a normally dry fire system.  This subject is covered in  Section 12.
3.3.4    Water quality
         Water quality is equal in importance to any aspect of  public
utility concern.  Where the water source is concerned, however, quality
need not be given highest priority since raw water can be treated  to make
it potable.

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                                 3-16
   TABLE 3-3.  FIRE FLOW, FIRE RESERVE AND HYDRANT SPACING RECOMMENDED
               BY THE NATIONAL BOARD OF FIRE UNDERWRITERS


Population
1 000
9 nnn
Z UUU
4 000
(. nnn
D UUU
10 000
1 1 nnn
_L j UUU
17 000
o o nnn
27 000
/. n nnn
t-U UUU
c c nnn
J J UUU
7 s nnn
Q R nnn
7 J UUU
i 9n nnn
_LZU uuu
i ^n nnn
J.JU UUU
9nn nnn
zuu uuu
Fire

gpm*
1 000
i >;nn
1 JUU
2 000
2c;nn
JUU
3 000
3cnn
JUU
4 000
A ^nn
** JUU
5 000
6 nnn
UUU
7 nnn
/ uuu
8 nnn
uuu
9 nnn
uuu
i n nnn
_LU UUU
Unnn
uuu
i 9 nnn
_i_z uuu
Flow

mgd*
1.4
9 9
Z. Z
2.9
0 
J.O
4.3
5n
.U
5.8
A ^
o. j
7.2
8
. o
in i
1U. 1
Uc
. J
iin
1J . U
1 L L
it . t
1 ^ H
-L J . O
17 ^
i/ . J
Fire
Reserve
MG*
0.2
Oc
. J
1.0
1 C
1 . J
1.8
9 1
Z.I
2.4
9 7
Z. /
3.0
i ^
J.o
/i 9
4 . Z
A Q
t- . o
^ A
J.H
A n
A ft
7 ?
1  {-
Area
Engine
Streams
120 000
110 000
100 000
90 000
85 000
sn nnn
ou uuu
7n nnn
/ u uuu
An nnn
c c nnn
J J UUU
/, Q nnn
/. o nnn
/, n nnn

per Hydrant,
sq ft*
Hydrant
Streams
100 000
on nnn
yu uuu
85 000
70 nnn
/ o UUU
70 000
55 000
40 000***







                                        o
*   Conversion factors:  gpm x 5.450 = m /d
                         mgd x 4.381 x 10~2 = m3/s
                         MG x 3785 = m3
                         sq ft x 0.0929 = m2
**  For populations over 200,000 and local concentration of  streams,  see
    outline of National Board requirements.
*** For fire flows of  5000 gpm and over.

         The concern for quality of a water source  is  based  primarily
on the ease with which the water may eventually be  treated and  the  cost
for the treatment required.  Reliability in quality is of equal
importance to reliability in quantity.
         Groundwater quality.  Water taken from above  permafrost  (supraper-
mafrost water) must be considered of questionable quality since contamina-
tion by pit privies and septic systems can easily occur.  Subpermafrost
waters are generally unpolluted but may contain high concentrations of
iron (as high as 175 mg/L), magnesium and calcium as well as organics.

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                                  3-17
Iron and hardness  below 7 mg/L and  100 mg/L,  respectively,  are reasonably
easy to remove  during  treatment  and  do not  detract from the value of the
source.  In  the  highly mineralized  areas  of Alaska,  some groundwaters
have been  found  to contain  unacceptably high  quantities of  arsenic.
Extremely  high  concentrations of nitrates have  been  observed in other
groundwaters near  Fairbanks, Alaska,  and  Nunivak Island.
         Surface water quality   Surface waters  are more readily polluted
by man; thus emphasis  should be  placed on bacteriological and biological
quality of the  water and watershed.   It has been demonstrated that
bacteria live for  long periods in cold waters and pose  a potential health
problem for  significant distances downstream  from their entry point.
         Water  sources should be selected and the watershed protected in
a manner acceptable in any  climate.   The  U.S. Public Health Service  [6]
divides water sources  into  three categories:  Group  I water may be used
as public water  supplies without treatment; Group II water  may be used
after disinfection only; and Group  III waters require complete conven-
tional treatment including  coagulation, sedimentation,  filtration and
disinfection.   Because of the high  probability  of contamination of
surface waters  by  wild and  domestic  animals harboring various tapeworms
which cause hydatid disease in man,  it is recommended that  all surface
waters be  filtered  prior to use  in  the public water  supply.
         Surface water sampled for  quality  during warm  weather may
indicate misleading values.  Freeze-rejection of minerals and other
impurities during  ice  formation  causes the  remaining liquid to be of
significantly poorer quality.
         Lake water quality improvement.  It  may be  possible to improve
the quality of water in a small  saline pond or  lake  by  pumping out the
concentrated brines which remain under the  ice  near  the end of the winter
and allowing fresh  spring runoff to  replace it.   Repeated one or more
times, this method may permit the use of  an initially unacceptable water
body as a  source of supply.  The U.S. Public  Health  Service,  in develop-
ing an improved  water  source for Barrow,  Alaska,  used this  method with
good results.  Total dissolved solids concentration  in  the  lagoon was
about 7000 mg/L  when ice cover was  fully  developed.   The range of total

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                                 3-18
dissolved solids in  the lake  is  shown  in Figure  3-4.   In  April  1976,  326
million litres of brine was pumped  from beneath  the  ice,  resulting  in
water of much higher quality.
3.4      Structures
         Structures  relating  to  water  supplies range  from a simple
temporary intake on  river  ice  to a  complex  dam on  permafrost  with a year-
round intake and pumping station.   Wells and  their appurtenances  are
also considered as supply  structures.
         It is not the intent  of this  discussion to  provide a guide for
structural design of any facility but  rather  to  point  out features  which
may require special  attention  in cold  climates.  Designs  should be
prepared by engineers qualified  to  work in  cold  regions.
3.4.1    River intakes
         Intake structures may be either temporary or  permanent.
Permanent structures are more  desirable because  they  permit a certain
freedom from attention at  critical  times such as during freeze-up and
breakup.  On the other hand,  temporary structures may  be  less expensive
and permit a degree  of latitude  of  operation not afforded by  permanent
structures.  Also, because temporary facilities  may  require attention
during critical times of the  year,  they force the operator to become
aware of existing or potential problems.
         Depending upon the overall system  design and  source  capabili-
ties, intakes may only be  required  for a short period  each year.  If
demands are such that they cannot be met by providing  storage,  then more
elaborate intake works will be required.
         Under some  conditions a protected  pump  on the river  shore  or on
the ice may suffice.  This requires little  design attention or  continuing
operator attention (see Figures  3-5, 3-6 and 3-7).   The reverse is  true
of permanent intakes.
         Numerous arrangements and  configurations of  river intakes  have
been designed with varying degrees  of  success.   Figure 3-8 shows  the
piping schematic for a matched pair of intakes in  the  Great Bear  River  at
Ft. Norman in the Northwest Territories.  Such designs are continually
evolving to make use of more  sophisticated  concepts  and materials.

-------
o
                                     o
                                     o
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                                                    Total dissolved solids (mg/L)
                                     O
                                     O
                                     O
                                                                         W
                                                                         O
                                                                         O
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                                Brine pumped from beneath the ice
                                       during this period
                               Spring break-up
                            Spring break-up
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                     3-20
   FIGURE  3-5.   WATER  TRUCK  FILLING AT WATER
                LAKE IN CAMBRIDGE BAY, NWT
 FIGURE 3-6.  WATER INTAKE AT FORT McPHERSON
              NWT                           '
FIGURE 3-7
INTAKE HOUSE IN PEEL CHANNEL
AT AKLAVIK, NWT

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                                 3-22
         Open water intakes in cold regions are  jeopardized  by  flowing
ice during freeze-up and breakup and must be given  special attention.
         Figures 3-9 and 3-10 show a water intake at  Cambridge  Bay in  the
Northwest Territories of Canada.  Note  that the  intake  line  is  installed
to allow water to flow  to the wet well  by gravity so  that  even  if the
intake itself were damaged, water would  remain available  at  the pump.
Note also the construction details, such as insulation, wet  well heater,
heat trace for intake line and recirculation line from  townsite.
         Use of multiple intakes is a recommended approach which may
enhance system reliability.  An intake  normally  submerged  in the summer
may be high-and-dry late in the fall when streamflow  has  been reduced  by
freezeup.  Further reason for multiple  intakes is the option that
provides for continuously circulating water to minimize ice  cover and
prevent freezing of the intake system.
         Frazil ice is  a phenomenon which occurs during freeze-up and
creates problems for operation of  river intakes  in  open water.   Frazil
ice occurs as ice forms in flowing water which is slightly colder than
0C (supercooled) and from which heat is continually  being lost.
Frazil ice adheres to and builds up on  any  submerged  object  it  contacts,
including itself.  Thus intake screens,  trash  racks and the  like may
become choked by frazil ice in a matter of  hours.   Frazil formation can
be prevented by locating the  intake in  a reach of  river where surface ice
forms before the water  is supercooled,  such as  in a long, calm reach.
Surface ice cover prevents  rapid heat loss  from  the water and thus
precludes frazil formation.   Heating  the intake  works bar screens and the
like  to 0.1C will remove supercooling  properties and prevent frazil
ice accumulation.
3.4.2     Infiltration galleries
          Infiltration galleries  offer  some  advantages over conventional
river or  lake  intakes.  The most  obvious is to  remove the structure from
the river and  the hazards  imposed  by  ice during  freeze-up and breakup.
Infiltration galleries  may  be placed  in the thaw bulb of streams  in
permafrost  areas and  collect  water even when  the streams appear  solidly
frozen.   Usually  some  flow  of water will occur within the streambed
itself,  particularly  when  the bed  material  is relatively coarse.

-------
                                             -packed PO-r^ne *****
                                                                                      Normal water level

                                                                        Estimated low water level
Chain hoist

     Electric space heater
                                                HWL-4J1
                                                     
      Vertical turbine
      supply PumPs
                                                                                 Estimated bottom of
                                                                                 ice level           intake
                                                 Electrical panel
                                                       polystyrene insulation

                                                              trace cable
       HWL TV:"'
       LWL ^rr
                          i- Intake valve
^     vVetwell  /.
^    heating coil
                                                                                                                N3
ii^'intake screen
                          (Not to scale)



-------
                                 3-24
                  FIGURE 3-10.  WATER SUPPLY UTILIDOR AT
                                COPPERMINE, NWT
         A second benefit offered by the infiltration gallery is the
filtration of the water by the materials surrounding the collectors.
This may be a very significant advantage in streams which carry a load of
suspended material such as silt or glacial rock flour.
         Infiltration galleries may be constructed parallel to the water
course, across the water course, vertically, or radially.  Schematics of
such systems are shown in Figure 3-11.
         Galleries must be protected against freezing, especially in perma-
frost areas.  Some sort of heating system  is usually installed during con-
struction.  Both electric and steam heating systems have been
successfully used.  Usually steam lines are placed on the upper surface
of the lateral and a second steam line is  installed 0.4 to 0.6 metres
above the lateral.
         Insulation with snow is another way to reduce frost penetration
However, to be effective, the area should  receive no traffic in order to
preserve the uncompacted snow cover [7],
         Periodic gallery cleaning may be  necessary to remove  silt and
other sediments which enter the laterals and sumps.  The use of modern
filter fabrics may reduce this requirement and improve overall system
performance.

-------
                                                            Pumphouse ]
                                                                               Horizontal gallery
                                 Horizontal gallery
Water stratum
                     Radial gallery
                                                      Water stratum
                                                                                               Gravel packed ditch
                                                       Vertical gallery
                                                                                                                           to
                                                                                                                           Ln
French drain
                                    FIGURE 3-11.   INFILTRATION GALLERIES

-------
                                 3-26
         Springs can be developed by  installing  horizontal  infiltration
galleries in the aquifer.  This  is a  generally approved  method  since it
reduces the possibility of water contamination at  the  point of  collec-
tion.
3.4.3    Wells
         A producing well is most successfully located  through  detailed
examination of geologic conditons:  kinds  and permeabilities of soils and
rocks; position of layers; character  of  cracks,  fissures and other large
openings; and a study of performance  records of  other  wells in  the area
[8].  Especially in arctic regions, professional hydrogeologists familiar
with permafrost should be consulted during  the preliminary  stages when
considering groundwater as water supply  source.
         In all cases, wells must be  located a safe  distance from
potential sources of pollution.  Local health departments usually have
specific requirements but in the absence of other  guides, wells should be
at least 60 m from the nearest source of pollution.
3.4.3.1  Well drilling.  There are several  opinions  on  the  best method
for drilling water wells.  Locations, accessibility,  size of well required
and other such factors will influence the  methods  used.   The U.S. Public
Health Service, Indian Health Service, Office of Environmental  Health
believes that because of equipment transportability, cable  tool drilling
is superior in remote areas.  "Jetting"  of  smaller wells has the advantage
of relatively low cost and the machinery is easier to  move  into remote
areas.  Cable tool systems require less water for  the  drilling  operation
than the jetting method, although most water used  in drilling can be
reused.
         Jetting combines hydraulic action  and thawing,  relying upon the
volume of water rather than high pressure  to "drill" the well.   A stream
of water is directed down into the ground,  gradually thawing the soil
which is washed away in the water.  Water  may be reused  repeatedly by
recirculating through a settling basin to  remove cuttings.   Jetting is
best suited to frozen soils which are primarily  sand,  silt, clay, or a
combination of these.  The system is  not effective in  regions where there
are large rocks or layers of rock to  be  penetrated.

-------
                                  3-27
         Cable tool drilling  uses  the  weight  of  a "string" of drilling
tools to penetrate through  all  varieties  of  soil and rock.  Progress may
be from 1.5 m to more  than  30 m per  day,  depending upon geologic condi-
tions.  Tools are lifted, dropped  and  turned  regularly; this pulverizes
the soil or rock and allows it  to  be suspended and carried away by a
minimal amount of water  and a bailer.   In hard formations, no casing is
required until the well  is  completed.   However,  in sand,  silt or clay (or
organic) soils the string of  tools is  operated inside the well casing.
The casing is usually  driven  into  the  ground  and then the well drilled
inside.  This procedure  is  repeated  in a  leap-frog manner until a water-
bearing stratum is penetrated.
         Rotary drilling machinery may also  be used in all types of
geological formations, but  involves  considerable expense  for equipment,
and reasonable degree  of operational experience  and skill.  Whereas
jetting and cable tool drilling equipment may be "broken  down" for
transport in light aircraft,  rotary  drills are not as small nor as easily
moved to remote locations.  Rotary drills are, in general, much faster
than other means of drilling.   As  with cable  tool drilling, a small
amount of water is used  with  the rotary drill.   A special Bentonite
"drilling mud" pumped  down  through the drill  stem and out through ports
in the drill bit and subsequently  to the  surface carries  away the
cuttings.  The drilling  mud coats  the  sides  of the hole and protects it
from scouring action of  the water.   Drilling  mud is used  over and over
during the drilling operation after  the cuttings have been removed.
         In some instances  it may  be necessary to heat the drilling fluid
during the operation,  such  as when drilling  through frozen soil under
winter conditions.  The  heated  fluid prevents the mud from freezing in
the permafrost and aids  in  thawing as  the drill  penetrates.
         Air rotary drilling  is a  variation  of rotary drilling which
employs pneumatic rather than hydraulic action to carry cuttings away
from the drill.
3.4.3.2  Well seals.   Sanitary  well  seals on  top of well  casings will
prevent contamination by surface sources  and  still permit easy removal of
the pump when necessary.  If  pumps and  pipes  to  the building can be

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                                 3-28
installed below the seasonal frost line, a single  pipe  from  the  well  will
suffice.  However, if the well is installed in  permafrost  or pipes  cannot
be installed below seasonal frost, some method  will  be  required  to  prevent
freezing of the well.  One such system is illustrated in Figure  3-12.
The use of Bentonite grout instead of cement provides an adequate seal
and reduces the possibility of frost heave damage  to the well  casing.
3.4.4    Pumping stations
         Pumphouses can provide shelter for pumping  equipment  controls,
boilers, treatment equipment and maintenance personnel  who must  operate
and service the facility.  Structural design will  depend on  the  require-
ments of each location and must be considered individually.   Equipment
housed within the shelter will also depend on the  individual system and
may vary from a simple pump to a complex system with boilers for heat
addition, standby power, alarm systems to alert operators  of malfunction
and the like.  Any system must provide the degree  of redundancy  and
safeguards required by the nature of the operation and  location. Figure
3-13 shows the pumphouse at Rankin Inlet, Northwest  Territories.
         More elaborate pumphouses will include redundant  pumps, standby
power sources and alarm systems to alert the operator in the event  of
failure.  Voltage control devices are recommended  to protect electrical
equipment where power is of questionable consistency or dependability
(see Figure 3-14).
         All pumphouses should be designed with moisture-proof floors since
water will be on the floors frequently.  Pumphouses  in  cold  regions must  be
large enough to accommodate additional equipment  such as heaters and  their
controls.  Oversizing the original pumphouse at an installation  should  be
considered carefully in relation to design life and  the accuracy of
demand predictions.
         Heat addition at the  source is usually desirable  since  the water
will be very cold, often approaching 0C.  Protection  from freezing,
then, is the overriding reason for heating water  at  the source,  although
there are also difficulties associated with treatment of very cold  waters.
Enough heat must be added to at least compensate  for heat  lost in  trans-
mission.  It is generally accepted that water in  transmission lines should

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                                         3-29
Jet pump pitless adapter (altered)
      Machined out area
      between the two
      passage ways in adapter

                     25 Plug

      Air inlet to allow water
      to drain out of drop pipe
      to submersible pump
         FROST PENETRATION
0.5C Water from submersible pump
                                                Sanitary well seal
                                                25 Pump lift pipe

                                                100 Casing

                                                Frost heave protection where necessary
                                                Electric wire for submersible pump
                                                25 Hot water from pumphouse (4.5C)
40 Mixed hot and cold  water from well (3.5C) 
40 Check valve to prevent hot
water from going into well when
submersible pump is not operating

40 W.I. Pipe

Allow for movement around
the connection (insulation, etc.)
                                  FIGURE 3-12.  WELL SEAL

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                            3-30
   FIGURE  3-13.   PUMPHOUSE  AT WILLIAMSON  LAKE
                    AT RANKIN  INLET,  NWT
                                             Vent
                                             Chlorine tank
Vertical turbine deep well pumps
                                          360 Swing beam crane
                                                Fixed beam
   Future pump installation

                \
                                                      Chlormator
                                                      Indicating, recording
                                                      and control
             FIGURE  3-14.   PUMP  STATION

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                                  3-31
be at least 4C to  provide an adequate margin  for  heat  loss  in the  event
of a pump failure.
3.4.5    Transmission lines
         Pipelines  carrying water  from the  intake  and pumphouse to  the
storage reservoir may be either buried or laid  above-ground,  depending
upon local conditions.  In general, buried  lines are preferred to reduce
maintenance and heat loss.  Surface or elevated lines must have additional
insulation and should be protected from climatic and physical abuse which
is likely to occur.  All pipelines should be provided with some form of
heat tracing or thawing method.  More detailed  design information is
covered in Sections 6 and 15.
         Pumps and  transmission lines should be provided with drains,
preferably automatic, to evacuate  the water in  case of  power  loss or
other long-term failure, and thus  prevent rupture  due to freezing.   These
essential provisions may be as simple as the elimination of  check valves
and providing positive gradient.
3.5      References
1.  Slaughter, C.W., Mellor, M., Sellmann, P.V., Brown, J.,  and Brown, L.
      "Accumulating Snow to Augment the Fresh Water Supply at Barrow,
      Alaska".  U.S. Army, Cold Regions Research and Engineering
      Laboratory.   Special Report  217, Hanover, New Hampshire,  January,
      1975.
2.  McFadden T., and C. Collins, "Case Study of a  Water Supply for  Coastal
      Villages Surrounded by Salt Water", Cold Regions  Specialty Conference,
      17-19 May, 1978, Anchorage, Alaska, American Society of Civil
      Engineers, New York, N.Y., 1978.
3.  Smith, M.W. and C.T. Hwang, "Thermal Disturbance due to Channel Shifting,
      Mackenzie Delta, N.W.T, Canada" In:  North American Contribution to
      Permafrost Second International Conference,  13-28 July,  1973,
      Yakutsk, U.S.S.R., National Academy of Science, Washington, D.C.,
      pp. 51-60, 1973.
4.  Alter, A.J. "Water Supply in Cold Regions".  Cold Regions  Science and
      Engineering Monograph III-CS2.  U.S. Army, Cold Regions  Research
      and Engineering Laboratory.  Hanover, New Hampshire, January,  1969.

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                                 3-32
5.  Reed, S.C. "Water Supply in Arctic Regions".  New England Waterworks
      Association.  Vol. 84 (4), December, 1970.

6.  U.S. DREW.  Public Health Service.  "Manual for Evaluating Public
      Water Supplies", PHS Pub. No. 1820, Washington, D.C., January, 1969.

7.  Feulner, A. J.  "Galleries and Their Use for Development of Shallow
      Ground Water Supplies with Special Reference to Alaska".  U.S.
      Geological Survey Water Supply Paper 1809-E, Washington, D.C., January,
      1964.

8.  Longwell, C.R. and Flint R.F. Physical Geology.  John Wiley & Sons,
       New York, 1955.
3.6      Bibliography

    Alter, A.J. "Arctic Environmental Health Problems".  CRC Critical
    Reviews in Environmental Control, Vol. 2, pp. 459-515.  January, 1972.

    Babbitt, H.E., Doland, J. James and Cleasby, John L. Water Supply
    Engineering.  McGraw-Hill, 1962.

    Campbell, Michael D. Water Well Technology.  McGraw-Hill, New York, 1973.

    Dickens, H.B. "Water Supply and Sewage Disposal in Permafrost Areas
    of Northern Canada".  Polar Record. Vol. 9, p. 421, 1959.

    Eaton, E.R. "Thawing of Wells in Frozen Ground by Electrical Means".
    Water and Sewage Works, Vol. Ill (8), August, 1964.

    Foulds, D.M. and Wigle T.E., "Frazile-the Invisible Strangler".
    Journal AWWA. Vol. 69, No. 4, p. 196, April, 1977.

    Gordon, R.C. "Winter Survival of Fecal Indicator Bacteria in a
    Subarctic Alaskan River".  U.S. Environmental Protection Agency
    Report EPA-R2-72-013, Washington, D.C., 1972.

    Heinke, G.W. "Sanitation for Small Northern Communities:  Some
    Problems and Goals".  Canadian Journal of Public Health, Vol. 62,
    1971.

    Hostrup, Lyons and Assoc. "Study of the Mechanical Engineering
    Features of Polar Water Supply".  U.S. Naval Civil Engineering
    Research Lab. Contract No. y 27491.  August, 1953.

    Karr, W.V. "Groundwater, Methods of Extraction and Construction".
    International Underground Water  Institute.  1969.

    McKee, Jack Edward and Wolf, Harold W., "Water Quality  Criteria".
    The Resources Agency of California.  Publication #3-A,  Sacramento,  1963.

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                             3-33
Page W.B., Hubbs G.L., Eaton E.R., "Report on Procedure for Jetting
Wells".  Arctic Health Research Centre, Fairbanks, Alaska, May, 1958.

Rice, E.F. and Alter A.J., "Water Supply in the North".  The Northern
Engineer.  Vol. 6 (2), 1974.

U.S. Arctic Health Research Centre, "Technical Information on Water
Supply Management for North Slope Activities".  Report No. 106,
Fairbanks, Alaska, 1970.

U.S. Department of the Navy, Naval Facilities Engineering Command.
"Cold Regions Engineering Design Manual", NAVFAC DM-9.  Alexandria, Va.,
March, 1975.

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                                 SECTION 4
                              WATER TREATMENT
                                   Index
                                                                     Page
 4         WATER TREATMENT                                             4-1
 4.1       General                                                     4-1
 4.2       Process  Design                                              4-1
 4.2.1     Heat  addition                                               4-2
 4.2.2     Coagulation  and  flocculation                                4-4
 4.2.3     Sedimentation                                               4-6
 4.2.4     Filtration                                                  4-6
 4.2.5     Adsorption                                                  4-8
 4.2.6     Disinfection                                               4-8
 4.2.7     Fluoridation                                               4-9
 4.2.8     Water  softening                                             4-10
 4.2.9     Iron  removal                                               4-10
 4.2.10    Colour removal                                              4-11
 4.2.11    Organics removal                                            4-11
 4.2.12    Desalination                                               4-12
 4.2.13    Ozonation                                                   4-13
 4.3       Plant Design                                               4-14
 4.3.1     Buildings                                                   4-14
 4.3.2     Ventilation                                                 4-15
 4.3.3     Lighting                                                    4-15
 4.3.4     Controls                                                    4-16
 4.3.5     Standby equipment                                           4-16
 4.3.6    Miscellaneous considerations                                4-16
4.4      Reference                                                   4-17
4.5      Bibliography                                                4-17

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                             List of Figures
Figure                                                              Page
 4-1     Dissolved Oxygen Saturation Variation with Temperature     4-2
 4-2     Viscosity of Water at Atmospheric Pressure                 4-5
 4-3     Viscosity Effects versus Temperature                       4-5
 4-4     Settling Detention Time versus Temperature                 4-7
 4-5     Building Partially Insulated with Earth Banks              4-15
                             List of Tables
Table                                                               Page
 4-1     Upflow Clarifier Loading Rates                             4-7
 4-2     Fluoridation Requirements                                  4-9

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                                   4-1
 4        WATER TREATMENT
 4.1      General
          The objectives of water treatment in cold regions are identical
 to those in other areas - to provide high quality potable water to
 improve and sustain health and eliminate the spread of waterborne
 disease.
          Under most conditions the treatment methods used in cold regions
 are the same as those in temperate climates.  However, temperature has a
 significant effect on many processes in water and wastewater treatment,
 sometimes requiring adjustment In design and operation.
          Water is susceptible to a change of state at temperatures of
 0C or less unless properly protected.   When means of replenishing
 lost heat fail, freezing may occur even when pipes and tanks have been
 insulated.   For this reason and because treatment is simplified when
 water is relatively warm (> 5C), it is common practice in cold
 regions to  add heat to water prior to or as  a part of the treatment
 process.
          Cold  climate conditions require that special attention be given
 to certain  aspects of treatment plants  and  processes.  Although these
 considerations sometimes seem trivial,  failure to attend to  them may
 cause serious  difficulty in achieving desired objectives.
          Quality standards have been established for drinking water in
 the  United  States and Canada.   These standards are presented only as a
 guide since provincial or  state standards may be more restrictive.
 4.2       Process  Design
          Standard water treatment processes  may need to be modified when
 they  are  applied  to cold waters.   An alternative to  process  modification
 is  the  option  of  adding heat  as a pretreatment operation; sometimes both
methods are  used  together.
          Water  treatment involves chemical,  physical  and biological pro-
cesses which are,  to  a greater  or lesser extent,  temperature sensitive.
 "Cold water" is  the term used  to  describe water  in the  temperature range
of 0C to about  5<>c.   Exact definition  of the  range  is  not intended
nor is it required  since changes  are  continuous  with  temperature.

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                                  4-2
4.2.1
Heat addition
         Heat addition  is often  practiced  to  protect  the  distribution
system.  When heat is added prior  to  treatment,  other benefits accrue.
Also, as an alternative  to modifying  unit  process  designs to  compensate
for low temperature, the designer  may choose  to  add heat  to  the water as
a preliminary treatment  step.  The annual  temperature variation for
surface waters in cold  regions varies from 0C to  about  20C.   By
adding heat during the  period when the water  is  cold, other  treatment
processes may be used essentially  unmodified.  Higher sedimentation and
filtration rates and reduced mixing times  result,  and overall  plant
requirements for space  and energy  are reduced.   Moreover, pumping
requirements for warm water are  lower than for cold water.
4.2.1.1  Corrosion control.  Cold  water  can absorb more  oxygen than
warm water.  Figure 4-1  shows the  variation of oxygen saturation with
temperature.  As water  is warmed,  oxygen is released. This  oxygen causes
iron and steel pipes, pumps and  tanks to rust.   By controlling the region
in which oxygen is released, corrosion within the  treatment  plant and the
distribution system may  be reduced.
             16
          O)
 c
 g
 2
 i5
 -i1
 CO
 co
 CD
 O)
 X
 O
 CD  4
             8
             0
               0
              4        8       12
                    Temperature (C)
16
20
  FIGURE 4-1.  DISSOLVED OXYGEN  SATURATION  VARIATION  WITH TEMPERATURE.

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                                   4-3
 4.2.1.2  Standardization.  Virtually all "package" type treatment systems
 are  designed for use with water warmer than about 5C.  If incoming
 water  is expected to be colder, heat must be added for the system to
 perform properly at design rates.   This allows the use of standard design
 in areas of varying water temperature.
 4.2.1.3  Method of heating.  Several methods of heating water may be
 used for equally satisfactory results.  It should be remembered that
 purity of drinking water is extremely important and any possibility of
 contamination must be avoided.
          Direct fired boiler.  This system uses a direct-fired oil, gas
 or coal furnace operated so that the water is maintained below boiling,
 usually at  about 90C.   Three basic types of boilers are 1)  water
 tube,  2) fire tube, and 3) cast iron water jacket.  The boiler must be
 operated in a manner which prevents cooling exhaust gases below the dew
 point.   Cold water may reduce exhaust gas temperature significantly and
 if condensation occurs  corrosion will reduce boiler and chimney life.
 Thermal efficiency is optimized when the boiler is operated  at the lowest
 temperature possible without  causing condensation of exhaust gases.
          Liquid-liquid  heat exchangers.   This system employs a closed
 vessel  containing a series of tubes.   An inlet and an outlet manifold  are
 provided for both the jacket  and the tube bundle.  Usually the hot liquid
 is circulated through the jacket and the liquid to be heated is
 circulated  through the  tubes.
          The source of  heat for this system may be a building or city
 central heating  system  or the  cooling water from an engine,  or any other
 suitable source.   Antifreeze  may be used in the hot fluid but caution
must be exercised  because of  the possibility of tube leak and cross-
connection.
          Blending.   Occasionally a  source of hot water is available which
can be  blended with cold  water  to achieve the  desired temperature.   Such
a source  may be  condenser water  from  a steam system.   Fairbanks,  Alaska,
successfully employed this  system of  warming cold well water.   In
Whitehorse,  Yukon  Territory, geothermal  water  is added to raw water  and
provides  a  very  substantial saving.

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                                  4-4
4.2.2    Coagulation and flocculation
         Coagulation is a chemical process  involving  the  destablization
of colloids.  It is slightly temperature-sensitive  in the range  from
0C to 30C.  Flocculation is the aggregation of  destabilized
colloidal particles to a size adequate  for  subsequent settling by gentle
mixing of the fluid in which the colloids are contained.   The inter-
particle contacts necessary for flocculation are  influenced  by fluid
viscosity.  Figure 4-2 shows viscosity  is inversely related  to
temperature.
4.2.2.1  Mixing.  Mixing is an important function in  water treatment
since it is required for flocculation and the dissolving  of  solids in
liquids.  Mixing is strongly dependent  on temperature because of changes
in the viscosity of the liquid.  Figure 4-3 can be  used  to make  the
necessary adjustments in design criteria for temperature-induced viscosity
changes.  It is plotted with 20C as the base level.   The power  input
for mechanical flocculation is directly dependent on  fluid viscosity, as
defined by:
         P = G2Vp                                                   (4-1)
where:  P  = power input (kW),
         i-\
        G  = velocity gradient (m/s/m),
        V  = tank volume (m ),
        U  = absolute fluid viscosity  (Pa/s).
         To maintain the same velocity  gradient in  the tank as the
liquid temperature decreases, it is  necessary to  adjust  the 20C
power requirement by the multiplier  from Figure 4-3.   This relationship
will be valid for any type of mechanical mixing.
         Detention time required for mixing is  determined separately.  It
is influenced by the time required for  desired  reactions  to occur and is
often arbitrarily based on successful  performance of  similar units.
Recommended detention times for flocculation of water range from 15 to 30
minutes.  Increasing this detention  time will compensate for lower water
temperatures.  The multipliers from  Figure  4-3  can  also  be used  for this
purpose.  Multiple basins in series  are the most  effective way  to increase
detention time, provided some basins can be bypassed  during warm weather.

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                                 4-5
1.0       1.1       1.2       1.3       1.4       1.5

                 Absolute viscosity (centipoises)
1.6
                                                                          0
      1.7    1.8
                                                                               O
                                                                               o

                                                                               CD
                                                                               :5
                                                                               03

                                                                               o>
                                                                               Q.

                                                                               E
                                                                               CD
      FIGURE 4-2.  VISCOSITY OF WATER AT ATMOSPHERIC PRESSURE
        Q_

        "5
            1.75
            1.50
            1.25
                                  Multiplier =  1.82 e03T
            1.00L

            o.oof	
                                     10         15

                                Temperature (C)
J	L
3
 20
         FIGURE 4-3.   VISCOSITY EFFECTS VERSUS  TEMPERATURE

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                                  4-6
         One alternative  to extended mixing  time  is  the  use  of  higher
chemical dosage.  Another  is  to adjust  pH  to  the  optimum for the
temperature of the water  being treated.  Optimum  pH  varies  inversely with
water temperature.  It  is  advisable to  evaluate each alternative since
one may be more economical.
4.2.3    Sedimentation
         Settling of particulate materials is  retarded by increased
viscosity in cold waters.  The settling velocity  of  particles is
proportional to the temperature as shown in  Figure 4-4.   Increased
clarifier size is recommended where cold water is to be  treated.
         Upflow clarifiers.   Upflow and sludge blanket clarifiers are not
as sensitive to low temperature as conventional clarifiers.   However,
temperature variations  may cause thermal currents which  can  easily break
through the sludge blanket and ruin efficiency.   Sludge  blanket and
upflow clarifiers should  be operated at nearly constant  temperatures.
Table 4-1 presents some recommended loading  rates for upflow clarifiers
which employ tube modules.
4.2.4    Filtration
         Filtration is  affected by low  water  temperature to  the extent
that head losses through  the  filter are proportional to  viscosity.  The
relative head loss changes about 3.5% per  degree  Celsius temperature
                                                       o  }
change.  Normal sand filter loading rates  are  about  5 mj/m h
                                               O   r\
and mixed media filter  loadings are about  12  m /m h. Therefore,
multi-media filter beds would provide more efficient use of  space in cold
climate facilities.  The  multiplier values from Figure 4-3 should be used
to reduce filtration efficiency.  For example, if the initial design head
loss is 1 m at 20C it  will be about 1.5 m at  5C.
         Backwashing of filters is also affected. Power for pumping will
vary as shown on Figure 4-2.  Adjustments  for  filtration and backwashing
are based on viscosity  changes.  However,  the  minimum upflow velocities
or wash rates to fluidize  and clean filter media  will be reduced because
of increased fluid density.   For example,  if  it takes a  velocity of 0.09
cm/s to fluidize a sand bed at 20C it  will  only  require 0.06 cm/s at
5C.

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                                       4-7
     2.00
     1.75
jj   1.50
Q.
     1.25
     0.75

        0
         0
              35
40
    Temperature (F)
45        50        55
60
65
                    10
                            15
                20
             FIGURE 4-4,
             Temperature (C)
   SETTLING DETENTION TIME VERSUS TEMPERATURE
                    TABLE 4-1.  UPFLOW CLARIFIER LOADING RATES
     Overflow rate based on total
     clarifier area and temp, less
     than 4C.
     Overflow rate based on area of
     clarifier covered with tubes.
     Temperature less than 4C.
      3, 2               ,  2
     m /m  h          gpm/ft
       6.1
       8.6
 2.5
 2.5
                       Overflow rate based on total
                       clarifier area and temp.
                       greater than 10C.
3, 2 ,
m /m h
3.7
4.9
2
gpm/ft
1.5
2.0
3,2,
m /m h
4.9
6.1
2
gpm/ft
2.0
2.5
                       Overflow rate based on area of
                       clarifier covered with tubes.
                       Temperature greater than 10C.
                        3.2               ,2
                       m /m  h          gpm/ft
               4.9
               7.3
   2.0
   3.0

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                                  4-8
4.2.5    Adsorption
         Adsorption is an exothermic process and in  the range of 0C
to 20C is essentially unaffected by temperature change [1,2].
4.2.6    Disinfection
         Disinfection is the process of destroying or  inactivating
disease-causing organisms in the water.  Traditionally, disinfection  has
been directed toward reduction of bacteria and is probably  not  as
effective in destroying either viruses or cysts.
4.2.6.1  Chlorine.  Chlorine has been almost universally  used as a
disinfectant for potable waters throughout this century.  The greatest
advantages are the ability to maintain and measure residuals, low cost
and economy of use.  Also, the availability of chlorine as  G-2  gas,
calcium hypochlorite Ca(OCl)2 and sodium hypochlorite  (NaOCl) make  it
possible to safely handle the disinfectant under a variety  of conditions.
Logistics and operator qualifications should guide the designer in
selecting the chlorine source.
         Solubility of chlorine is theoretically a factor in cold water.
However, chlorine is virtually never dosed at rates  which are insoluble
in water in the normal range of temperatures.
         In recent years there has been significant  concern over  the
byproducts created by using chlorine as a disinfectant in waters contain-
ing organic compounds.  It has been discovered that  some  organic
compounds form carcinogenic substances when exposed  to chlorine in  water.
As a result there is a growing trend away from pre-chlorination in  the
production of potable water.
         Chlorine disinfection is hindered by cold water.  Exposure time
must be increased as water temperature decreases.  Contact  time of  at
least one hour is recommended and residuals must be  maintained  throughout
the contact period to achieve the desired bacteriacidal effects.
4.2.6.2  Halogens.  Aside from chlorine, two other members  of the
halogen group have been used as potable water disinfectants.  These
elements are iodine and bromine.  Both substances have been tentatively
approved but their use has been primarily supplemental  to chlorine  in
swimming pools with only occasional use as potable water  disinfectants.

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                                   4-9
Costs for iodine and bromine cannot compete with  gaseous  chlorine (about
25 to 1); however,  iodine may  be  competitive  with some  forms  of  hypochlo-
rite.
         Iodine has the advantage over chlorine of  producing  minimal
tastes and odours in the presence of  phenols.  Also,  iodine can  be stored
in non-metallic containers  for extended  periods without appreciable loss
or deterioration.
4.2.6.3  Ozone.  Next  to elemental fluorine,  ozone  is the  strongest
oxidizer known and  as  such  it  is  an excellent  disinfectant.   Ozone also
has other possible  uses which  are discussed in Section  4.2.13.
         Ozone is only slightly temperature sensitive so  no appreciable
modification of standard technique is required.   However,  ozonation
equipment is expensive to install and operate.  Where cost is less
important than logistic consideration, ozone  has  the  advantage of being
generated from air  using electricity and is unaffected  by  resupply
problems in remote  areas.
4.2.7    Fluoridation
         Fluoridation of potable  water in cold climates requires  a higher
dosage because per capita consumption of drinking water tends to  be
somewhat less than  in temperate regions.  Normally, fluoride  concentra-
tion should be about 1.4 mg/L  in  cold regions.  Table 4-2  lists  the
recommended ranges of fluoride  in drinking water  at various annual
average air temperatures.
                  TABLE 4-2.   FLUORIDATION REQUIREMENTS
Annual average of maximum
   Recommended control limits
Fluoride concentrations in mg/L
daily air temperature*
C
12 and below
12.1 to 14.6
14.7 to 17.6
17.7 to 21.4
21.5 to 26.6
26.7 to 32.5
Lower
0.9
0.8
0.8
0.7
0.7
0.6
Optimum
1.4
1.1
1.0
0.9
0.8
0.7
Upper
2.4
2.2
2.0
1.8
1.6
1.4
  Based on temperature data for at least five years.

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                                    4-10
4.2.8    Water softening
         Water softening is often required in cold climates where
groundwater frequently contains high concentrations of calcium  and/or
magnesium hardness.  Two methods of softening are well developed:  ion
exchange and chemical precipitation.
4.2.8.1  Ion exchange.  Ion exchange water softening  is affected by  low
water temperature to the extent that it is essentially a  filter-type
system and flow is viscosity dependent.
         Waters derived from subpermafrost aquifers tend  to be  slightly
deficient in oxygen and as a result may contain relatively large amounts
of soluble forms of iron.  Iron can foul zeolite and  greensand  ion exchange
resins and must be removed prior to softening.  (See  Section 4.2.9).
4.2.8.2  Chemical precipitation.  Lime-soda softening is  frequently
used where water to be treated is turbid and requires clarification.
This process is affected by low water temperature since it involves
mixing, f]occulation, sedimentation, filtration and sludge handling.
4.2.9    Iron removal
         Iron is of considerable concern in waters in cold climate areas.
Iron is one of the most abundant elements in nature and its presence  in
varying amounts is to be expected.  It may exist in any of nine valence
states but Fe+^ and Fe -* are most important in water.  In addition
to elemental iron, organic iron complexes present problems.
         Limiting iron in water supplies is more for  aesthetic  purposes
than for health reasons.  Canadian Drinking Water Standards and
Objectives and the U.S. National Secondary Standards  for  drinking water
limit iron to 0.3 mg/L.
         High iron concentrations in cold climate waters  may be explained
as follows.  Groundwaters and waters beneath the ice  in ponds and shallow
lakes are deficient in dissolved oxygen.  As the water dissolves iron it
is oxidized to FeOH+, which is a highly soluble form.  In surface
waters where there is sufficient dissolved oxygen, much less soluble
Fe(OH)3 and Fe2C>3 are formed.
         Treatment of waters containing iron requires oxidation, which may
be accomplished by aeration or by chemical oxidation  with chlorine or ozone,
Simple aeration is not effective for removing iron/organic complexes.

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                                     4-11
          Low temperatures restrict the aeration process.  Although oxygen
is more soluble at low temperatures, overall gas transfer is lower.  This
is explained on the basis of viscosity, gas/liquid contact etc.
Furthermore, the type of aeration system influences gas transfer rates.
Compressed air systems are more efficient than mechanical surface-type
aerators.  Oxygen transfer coefficients have been evaluated over the
temperature range from 3C to 35C with the following results:
                                              /p   rj> N
          - for compressed air system = 1.024   0    2
                                            ff * T ")
          - for mechanical aerators = 1.016   0   2

          Coarse bubble diffusers tend to be more maintenance-free than
other types of aerators.  Aeration can be accomplished by cascade or
"waterfall" systems, but these tend to be associated with humidity
problems in the treatment plant.
          Aeration tanks should have a width to depth ratio of 2 to 1 or
greater to promote good mixing.  Detention time will be on the order of
10 to 30 minutes and the air volume range required will be 0.05 to 1.25
m3 per m3 water treated.
4.2.10    Colour removal
          Objectionable colour concentrations are frequently found in
water originating in tundra regions where organics are leached from
decaying vegetable matter.  Colour may be reduced or removed by chemical
oxidation with chlorine or ozone and with carbon adsorption.
4.2.11    Organics removal
          Organic materials in water, much like colour, are removed to a
limited extent by coagulation and sedimentation.  More complete removal
requires carbon adsorption or ozone treatment.
          Activated carbon Ls effective for removal of organics but when
granular carbon is used, there is a strong potential for enhancing
bacterial growth in the carbon bed.  Organics removed from the water
become food for micororganisms which may eventually be washed through the
carbon bed and into the product water.  Post disinfection is required in
this situation.
          Joint use of ozone and carbon adsorption has been found extremely
effective in organics removal and for treating iron-organic complexes.

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                                     4-12
Ozone destroys microorganisms and breaks  down  many  organics.   The remain-
ing organics are absorbed on the carbon beds.
4.2.12   Desalination
         In coastal areas of the Arctic and  in some areas  where  ground-
water sources are highly mineralized, desalination  may  be  required.
Several desalination methods are available including distillation,
reverse osmosis (RO) and freeze treatment.
4.2.12.1 Distillation.  Distillation  is the  best  known, most  highly
developed means of removing dissolved materials concentrations from
water.  Cold water increases the operational costs  of distillation
slightly.  The relatively high skill  requirement  for operators makes this
                                                                  o
an undesirable process  in remote areas.   Small stills (about  20  m /h)
require about 1 kg of diesel fuel for 175 kg product.
4.2.12.2 Reverse osmosis.  Reverse  osmosis (RO) uses mechanical  energy
to drive water through  a semipermeable membrane.  By proper membrane
selection water may be  produced which is  quite acceptable  for potable
purposes.  RO is temperature sensitive with  the best results  obtained
when water temperatures are in the  range  of  20C  to 30C.
         The cost of RO is relatively high due to equipment operation  and
maintenance requirements.  Small RO units are  available  in sizes from  3.5
m-Vday to 3500 m^/day.  These units require  about 2.4 kWh  of  power
for each cubic metre of water treated.  The  cost/benefit  ratio for RO
desalination is improved by the following factors:
         1)  higher water temperatures,
         2)  industrial/commercial  water  users,
         3)  sewers for brine disposal.
Reduction of the cost/benefit ratio is caused  by  the following:
                         /
         1)  high land  costs,
         2)  high electrical power  costs,
         3)  high population density  per  dwelling unit,
         4)  high interest costs.

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                                     4-13
         Actual costs  for RO in  the United  States  ranged  from 11 cents
per cubic metre of water for a town of  63,000 people  to 55  cents per
cubic metre for a town of 1250 people.
         RO treatment  systems must be protected  from  freezing at all
times.  Membranes which have been frozen  are unreliable even if freezing
has occurred during  shipping prior to installation.
4.2.12.3 Freezing.   Treatment by freezing  is a  system which may be
practical in cold regions where  the cold  may be  used  as a resource.   This
method is based upon the fact that as water freezes,  impurities are
slowly "refined" or  "salted out" and  the  ice contains only  pure water.
Three types of freezing processes have  been used  successfully in pilot
projects.
         The reservoir process involves freezing  a large  volume of water.
When ice containing  the desired  volume  of  water  has been  formed, the
brine below the ice  is withdrawn.  When the ice  is melted,  purified  water
is the product.
         Layer freezing involves a more complex  system of freezing
brackish water in successive sheets.  The  first  water melted off in  warm
weather is wasted because it contains most  of the  impurities.
         Spray freezing involves spraying  brackish water  through a modified
lawn sprinkler to form a cone of ice.   Pure water  is  frozen most quickly
and brine drains away  continuously throughout the  winter.  In a pilot
scale test in Saskatchewan, chloride  content was  reduced  from 2000 mg/L
to 500 mg/L for 75%  of the brackish water  sprayed  [3],  Estimated total
costs for the process were about 22 cents  per cubic metre of product.
4.2.13   Ozonation
         Ozone as a  disinfectant was  briefly covered  in Section 4.2.6.3.
However, European experience with ozone in  water  treatment  for many  years
has shown numerous benefits in addition to  disinfection.
         Iron and manganese are  effectively removed by oxidation with
ozone followed by separation.  Applied  early in  the treatment chain,
ozone rapidly oxidizes iron and  manganese  and aids in flocculation.
* 1977 U.S. dollars.

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                                    4-14
         Organics oxidation by ozone is accomplished by ozone addition  in
the middle of the overall process.  Followed by granular activated
carbon, this is very effective in removing organics and has none  of  the
side effects of taste and odour associated with chlorination.
         Ozone systems are expensive to build.  Costs  for  a system produc-
ing less than 450 kg/d (0^) are approximately $2200 per kg of daily
ozone production.  Operational cost, including amortization over  20
years, ranges from 1/2 cent per cubic metre to 1 cent  per  cubic metre of
water treated.
4.3      Plant Design
         There are several aspects of water treatment  plant design in
cold regions which are important.  Nearly all functions of water  treat-
ment must be housed for process protection as well as  for  ease of
maintenance and operation of equipment.  Certain unit  processes require
heated shelter, while others require shelter only.  Generally, processes
which include equipment such as pumps and exposed  piping must be  housed
and heated to prevent damage from freezing.  Water temperature, not  air
temperature, determines process efficiency.
4.3.1    Buildings
         Combining different functions under one roof  rather  than in a
group of smaller buildings reduces surface area and heating requirements.
Piping and electrical runs may be shorter and less expensive  initially
and possibly easier to maintain.  Possible expansion in the future should
be considered in selecting the single building concept.  The  floor plan
of cold region systems can be critical to building efficiency.  Designers
should place areas which require  stable heat in the building  interior,
and store rooms and other less vital functions against outer  walls.   In
this manner, heat lost from the interior is used to heat other  space
before escaping outdoors.  Building shape can be optimized to  reduce
surface area and oriented to take advantage of sunshine.
         Placement of some functions below ground  and  banking  buildings
with earth on outside walls will  reduce energy requirements (See  Figure
4-5).

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                                     4-15
                                            Fan forced ventilation
                                                 Controls
                                                 Process area
        FIGURE  4-5.   BUILDING PARTIALLY INSULATED WITH EARTH BANKS
          Vapour  barriers are very important  in cold climates and more
so  in  buildings  where  moist  air  is prevalent such as in treatment plants.
Poor vapour  barriers will permit moisture  to penetrate into wall and roof
insulation and reduce  its effectiveness.
4.3.2
Ventilation
         Ventilation  is  important  both  for  human  health and comfort and
building economy.  Moist  indoor  air  in  process  areas  must  be expelled to
prevent condensation  and  related problems.   Air may be reused from one
type of space  to another  to  economize on  the amount of warm-up required.
For example, air may  be moved  from office space to  lab space before
exhaust, or from office  to process areas.   If dehumidification equipment
is installed,  process  space  air  might be  reused in  either  office or lab
space.
         An alternative  to this  direct  reuse of air is to  extract heat
from warm, moist exhaust  air to  preheat incoming  fresh air.   Several
fairly efficient devices  are available  to perform this function.
         Continuous ventilation  may  not be  necessary  in all  spaces.  When
offices and labs are not  occupied  it is unnecessary to force ventilate
them and waste heat.
4.3.3    Lighting
         Adequate lighting is  important both inside and outside  treatment
plants; in cold northern  climates  it is particularly  essential because of
reduced wintertime daylight.   Controls for  lighting circuits  should be
designed so that minimum  light is  provided  in unoccupied areas with

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                                    4-16
supplementary lights available as needed.  Unless relatively small light-
ing circuits are provided, appreciable power may be lost to a function
not actually needed.
4.3.4    Controls
         Process controls are sensitive devices which may be adversely
affected by low temperature or high humidity.  Plant design should
provide controls on interior walls or in special cabinets away from the
influence of moisture and temperature.  Ventilation should be provided to
reduce the possibility of damage by atmospheric changes.
4.3.5    Standby equipment
         In cold regions equipment is subjected to rigorous conditions.
As a result, equipment failure may be more frequent.  Providing redundant
equipment may increase system reliability.
         It is recommended that the designer not place total reliance on
                                                           ^
one item if that reliance could as easily be placed on two smaller items.
For example, rather than one large pump, two or three smaller ones will
generally be more desirable.  This also permits periodic maintenance
without suspending operation entirely.
4.3.6    Miscellaneous considerations
4.3.6.1  Drainage.  Whenever possible, plants should be designed and
built so that they can be drained by gravity if necessary.  This is
particularly true in remote areas and at smaller installations.
4.3.6.2  Auxiliary power.  Auxiliary power supply should be provided to
support minimum operation of the treatment plant and distribution system.
4.3.6.3  Space/process trade-offs.  Under some circumstances the designer
may wish to evaluate the overall benefits of energy-intensive processes
which are space-efficient.  For example, pressure filters or pre-coat
filters which require pumping may have overall advantages compared to
standard or mixed media gravity filters.  Or in another case a centrifuge
may be preferable to a standard clarifier.
         In cold climates these trade-offs must be evaluated carefully
because heating requirements are significant.  Where plant expansion is
contemplated, these considerations may be particularly valuable by
allowing addition of capacity within existing space.

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                                    4-17
4.3.6.4  Replacement parts.  Plant management should maintain a  stock of

replacement parts for equipment subject to failure or wear.  This is

particularly important in remote areas where much time may be lost in

shipment of parts from sources of supply.

4.4      References

1.  Magsood, R. and Benedek, A., "The Feasibility of the Physical-Chemical
       Treatment of Sewage at Low Temperatures", IN Symp. on Wastewater
       Treatment in Cold Climates, Saskatoon, Sask., Aug. 22-24, 1973,
       E. Davis, ed., Environmental Protection  Service, Environment
       Canada, Report No. EPS 3-WP-74-3, pp. 523-548, Ottawa, 1974.

2.  Magsood, R. and Benedek, A., "Low-temperature Organic Removal and
       Denitrification in Activated carbon Columns", Jour. Water Poll.
       Control Fed., 49(10):2107.

3.  Spyker, J.W. and Husband W.H.W, "Desalination of Brackish Water by
       Spray Freezing", Saskatchewan Research Council.  EDC-73-CIV^,
       1973.

4.5      Bibliography

    Alter, Amos, J.  "Water Supply in Cold Regions".  U.S. Army Cold
    Regions Research and Engineering Laboratory, Monograph III-C52,
    January 1969.

    Twort, A.C., Hoather R.C.,  Law P.M., Water Supply, second ed.,
    American Elsevier Publishing Co.,  Inc., 1974.

    Wallis, Craig, Staff, Charles H.  and Melniok, Joseph L.,  "The Hazards
    of Incorporating Charcoal Filters into Domestic Water Systems".
    Water Research,  Vol 8, pp.  111-113,  1974.

    Weber, Walter J. Jr.  Physiochemioal Processes for Water  Quality
    Control.  John Wiley & Sons, Inc.,  1972.

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                                SECTION 5
                              WATER STORAGE
                                  Index
                                                                    Page
5        WATER STORAGE                                              5-1
5.1      Purposes and Capacity Requirements                         5-1
5.2      Tanks                                                      5-2
5.2.1    General                                                    5-2
5.2.2    Insulation                                                 5-3
5.2.3    Design                                                     5-8
5.2.4    Thermal considerations                                     5-9
5.2.5    Foundation                                                 5-11
5.2.6    Costs                                                      5-12
5.3      Earth Reservoirs                                           5-12
5.3.1    General                                                    5-12
5.3.2    Water quality                                              5-12
5.3.3    Dams                                                       5-14
5.3.4    Diked impoundments                                         5-14
5.3.5    Impervious liners                                          5-14
5.3.6    Foundations and thermal considerations in permafrost
         areas                                                      5-15
5.4      References                                                 5-18
5.5      Bibliography                                               5-19

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                             List of Figures
Figure                                                              Page
 5-1     Wood Tank with Insulation and Liner on Inside              5-4
 5-2     Steel Tank with Board Insulation and Metal Cladding        5-4
 5-3     Insulated Buried Concrete Tank                             5-6
 5-4     Above-Ground Concrete Tank, Greenland                      5-6
 5-5     Steel Tank with 75-mm Sprayed on Polyurethane
         Insulation, Barrow, Alaska                                 5-7
 5-6     Installation of an Impervious Liner in a Water Reservoir,
         Eskimo Point, NWT                                          5-16
 5-7     Liner Installation and Anchorage Embankments               5-16
                             List of Tables
Table                                                                Page
 5-1     Water Storage Tank Costs                                    5-13

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                                  5-1
5.       WATER STORAGE
5.1      Purposes and Capacity Requirements
         The total water storage requirement is  the  sum  of  flow equali-
zation, emergency and fire requirements.  The reliability of  the water
source and the community size, i.e., equipment and expertise  available, will
influence the storage requirements.  Typically,  these will  be two days total
water demand plus the fire requirements and any  seasonal requirements.
         Most piped and trucked water delivery systems will require  some
storage capacity to meet daily and hourly water  demand fluctuations.
This storage is called "buffer" or "equalization" capacity.   Piped
systems in small communities typically have a peak hourly consumption of
4.5 times the average daily consumption (see Section 4).  The storage
requirement for buffer capacity is generally one day's consumption.
Also, emergency storage of at least one day's water  requirement should be
provided.  Several days' supply may be necessary when the community  is
served by a long pipeline.  For trucked systems, storage of two days'
consumption within the community is desirable to breach  any supply
interruptions, and to act as buffer capacity where a piped  supply line
from the source is used.
         Storage capacity is also required to act as a buffer and
to breach temporary supply failures where limited-yield wells or
constant-flow treatment plants are used.
         Fire protection requirements for both piped and trucked systems
are outlined in Section 12.  These requirements  should be used  to
calculate the storage capacity needed.
         Water supply systems in some remote northern communities are
operational only on a seasonal basis.  Where a continuous water supply
cannot be obtained, is too expensive, or is impractical  to maintain,
enough water must be stored to supply the demand during  periods of supply
failure.  For example, where a temporary water intake system  is utilized,
short-term storage is required to supply the demand  when the  intake  is
inoperative during river or lake freeze-up and break-up.  Complete winter
storage has been utilized at locations where all water sources  cease,
freezeup, or are inaccessible during the winter.  A  water supply pipeline
from an inaccessible or distant water source may be  used in the summer to

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                                  5-2
fill a winter storage reservoir or  tank.   In  these  instances,  the
duration of the expected  source interruption  and  the  design  rate of
consumption will determine  the storage capacity required.  Local records
must be consulted.
5.2      Tanks
5.2.1    General
         Special cold regions design considerations and  problem areas
include:  icing conditions; insulation; heat  requirements; foundation  design
(particularly in frost-susceptible  soil);  the difficulty and high  cost of
carrying out maintenance  in remote  areas;  and other eold climate construc-
tion and operation and maintenance  (O&M) considerations  such as transporta-
tion, labour, logistics,  and weather (see  Section 2).  Tanks in cold regions
must be insulated and heat  added to prevent ice formation  in the tank.
         Common storage tank construction  materials are  wood,  steel and
concrete.  Small individual tanks of aluminum, plastic and fibreglass
have also been used.
         Wood tanks are particularly useful because they do not have to
be insulated.  They are relatively  light and  the  small pieces  can  be
easily shipped into remote  areas.   They can be erected by  local people
without expensive, special  equipment.  Wood tanks can leak by  sweating.
With very careful erection  and regular maintenance, such as tightening of
bands, leakage can be reduced; however, this  is not always easily
accomplished in northern  utility systems.  Any leakage during  the  winter
will result in icing on the outer surface.  This  ice  buildup is a
nuisance and can result in  damage to the tank and foundation.  Unlined
tanks should be operated with as little water level fluctuation as
practical since the wood  shrinks when it drys out, producing cracks.
Unlined wood tanks must be  allowed  to sweat; therefore,  they must  not  be
painted or coated.  Leakage problems can be overcome  by  installing a
flexible waterproof liner inside the tank.  The liner material must be
rugged enough to withstand  shipping and installation  handling, and may
require low temperature specifications (see section 5.3.5).  Wherever
possible, the liner should  be prefabricated, with the necessary openings
reinforced, and in one piece, to reduce the amount of field work and

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                                      5-3
allow complete replacement.   It is imperative to prevent ice formation
within the tank because this will damage the liner and punctures are
difficult to locate.  This is often impractical and is a major
disadvantag of membrane liners.  Where greater thermal resistance than
the wood itself is required, near-hydrophobic insulation may be placed
on the inside wall of the tank and covered with a liner (Figure 5-1).
          Steel tanks can be either bolted or welded.   Small tanks of
less than 200 m3 could be barged complete but larger ones must be
constructed on-site.  Bolted tanks ar quickly erected; however, any
damage to the plates during shipping will make alignment difficult and
leaks may occur.  Leakage at the joints may occuur due to misalignment,
poor erection or foundation movement.  The insulation and coating must
consider such movements and leakage.  Welding is the preferred method of
construction, particularly for large tanks (i.e., greater than 2000 m3).
However, qualified welders and vacuum and radiographic equipment to check
the welds are necessary.
     Special low-temperature, high-impact steels, such as ASTM A-516
or CSA G40.8, are advisable where the tank may remain empty during the
winter and reach the lowest ambient temperature.  The designer must
assess the risk of this situation.  Because of the high cost of special
steels, conventional steel has been generally used for insulated water
storage tanks.  Welded steel tanks have been insulated with polystyrene
or polyurethane boards and with sprayed-on polyurethane.  Figure 5-2
illustrates a welded steel tank with board insulation and metal
cladding.
          Steel tanks must have an anti-corrosion lining such as an epoxy
paint system.  The minimum temperature conditions required during the
installation and curing are significant to construction scheduling.
Failure to achieve this and follow manufacturer's instructions are major
causes of premature lining failures.  The cost of sandblasting and liner
installation is very high in remote locations; therefore, the liner system
should be selected for the best ovaerall economics, not just the initial
cost.  Alternatives such as membrane liners or electrical corrosion pro-
tection systems such as anodes or impressed current may be considered.

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                                         5-4
                 Access hatch
            Tank diameter = 9 6 m

                          Ladder
                   100 0 Overflow
          65 0 Recirculatmg return line
             Pipe and ladder support
                 Tank base
     300 x 300 mm Tank beams
     Wood pile at 1 4 m spacing
                                                           Wrap in 30 mil PVC liner material
                                                           Bolt
                                                           Tank shell
                                                           Polystyrene
                       LINER SUPPORT DETAIL

                     Liner
                     Tank shell
                     Two-25 mm layers of polystyrene board insulation
                           Metal jacket
                           50 mm Polyurethane insulation
                           300 0  Supply line and carrier pipe
                           Pipe support
                           Drift pin
                                                            Ground level
    FIGURE  5-1.    WOOD  TANK WITH  INSULATION AND  LINER ON INSIDE
                      (on pile  foundation)
                    Access hatch
               Metal cladding
                       M.
      Metal flashing
                                                            Tank roof
                                               50 mm Polystyrene board insulation
                                  - Insulation anchors at 600 mm spacing
                                   Welded steel tank wall
                                  25 mm Polystyrene board insulation
                                  -40 mm Polystyrene board insulation
 20 x 0 5 mm Stainless steel bands 450 mm spacing
 900 x 0 625 mm Metal (aluminum) cladding sheets
 approximately 12 m long
                                200 mm Gravel
                       -Tank floor
                       -Polystyrene board insulation
FIGURE  5-2.   STEEL TANK  WITH  BOARD  INSULATION AND  METAL  CLADDING

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                                       5-5
           Concrete  tanks  have been  used where  adequate  aggregate  is
 available  and  the foundation is  rock  or where  soils permit  slab
 construction.   They should be covered with earth where  practical  to
 reduce  heat  loss and insulated if necessary  (Figure 5-3).
 5.2.2      Insulation
           Insulation may  be earth cover, wood,  fibreglass batt,
 polyurethane or extruded  polystyrene  boards.   The typical 75-mm walls of
 wood tanks provide  some insulation  value, but  the thermal resistance of
 concrete and steel  is negligible.   The thermal inertia  of soil dampens
 out the extreme air and ground surface termperatures, while fibreglass,
 polyurethane and polystyrene provide  thermal resistance to  reduce heat
 loss.   Only  moisture resistant insulation should be installed in  contact
 with storage tanks  which  are inaccessible or below ground,  since moisture
 from leaks,  condensation, rain or groundwater  can drastically reduce the
 insulating value.
          Tanks of  any material  can be enclosed within  a building shell.
 Such an exterior frame and shell may  be constructed against the tank or a
 walkway may  be  provided between  the tank and the exterior wall (Figure
 5-4).   The wind protection and air  gap will reduce heat losses and
 this can be  further reduced by insulating the  enclosure.  Where access to
 the insulation  is provided, such as by a walkway, fibreglass batt
 insulation can  be used (Figure 5-4).
          Near-hydrophobic plastic  foam insulations are readily available
 and commonly used.    Polyurethane may be foamed on-site, reducing the
 shipping costs; however,  field costs may be higher.   Polyurethane boards
 may be  made up, but  the foam is more  commonly  sprayed directly onto the
 storage tank surface  (Figure 5-5).  To ensure a good bond to a metal
 surface loose scale  and paint flakes should be removed, the surface should
 be solvent-cleaned  if it  is oily and a compatible primer applied.   Foamed-
 in-place insulations are particularly useful for insulating curved sur-
 faces or places that are difficult to reach.   Spraying must not be carried
 out in the presence of water,  rain,  fog,  condensation, wind velocities
 greater than 5 km/h, when the  tank surface temperature is below 10C,  or
when the air temperature is below 2C without special techniques  and heating

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                                    5-6
 Backfill mound
Original ground level
                         Sloped
Rolled roofing and granular sufaced
50 x 300 mm Tongue and groove wood decking
       ^^-    mm Polystyrene board insulation

          Galvinized steel joists
                                        1 00 mm Polystyrene  board insulation
                                        250 mm Reinforced concrete walls and floor
                                              0.1 mm Polyethylene film
              FIGURE 5-3.   INSULATED BURIED  CONCRETE TANK

        Ventllatlon L=    ^Asphalt paper
                                             100 mm Rockwool batt insulation 
                          Inner tank
                              Radius = 5 7 m
                                                  Outer tank
                                            Radius = 8 2 m -
                     -Centre column
                     - Reinforced water-tight concrete

                          250mm      250mm-
                            I	
       300 mm
                            r
                           T

                                                                          Metal cladding
                                           Rock
         FIGURE  5-4.   ABOVE-GROUND  CONCRETE TANK,  GREENLAND

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                                   5-7
              FIGURE  5-5.   STEEL TANK WITH 75-mm SPRAYED
                            ON POLYURETHANE INSULATION,
                            BARROW,  ALASKA
equipment.   Quality must  be controlled during  and after foaming.  A high
degree  of skill  is  required in application to  ensure a smooth surface.
Polyurethane  foam must  be  protected from  vandalism,  weather and from
ultraviolet  light (sunlight).   This can be done  with low-temperature
elastomers or other coatings  compatible with polyurethane which are
sprayed onto  the insulation,  usually in two or three coats, with the
first coat applied  within  one  day of foam application.  The walls can be
further protected by  sheet  metal cladding.
         Extruded expanded  polystyrene or polyurethane boards can be
glued and strapped  (typically  with  40  mm  x 0.5 mm stainless steel
banding 450 mm on centre)  to  the outside  of tank.  Large tanks  will
require clips.  The boards  should generally be less  than 75 mm  thick to
allow installation  on the  curved tank  surfaces.   Two layers are
preferable so that  by staggering these, the joints can be covered.   The
insulation must be  protected  from weather,  and vandalism.  This is
commonly done with  metal cladding.   Embossed,  corrugated or ribbed
(i.e., not smooth)  surfaces will  not show bends  or deformities  incurred
during construction or operation.

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                                 5-8
         Near-hydrophobic insulation boards can also  be  used  to  insulate
the walls of below ground level concrete  tanks.  High density foams  with
compressive strengths up to 700 kPa can be placed under  a  tank,  if
desired (Figure 5-3).  These higher density foams also absorb less
moisture.
         Ice is a relatively poor insulator, l/60th that of polystyrene;
therefore, an ice growth on an insulated  tank wall does  not appreciably
reduce heat losses.  However, ice is 20 times a better insulator than
steel and an ice layer will reduce heat loss better than an exposed
surface.
5.2.3    Design
         Ice in water storage tanks can cause serious  damage.  A
floating ice sheet may destroy ladders, structural supports,  pipes and
similar interior appurtenances as it rides up and down in  the tank due
to fluctuations in water level.  If these are attached to  the tank wall,
failure can result.  Ice formed on the tank walls can  suddenly collapse,
e.g., when the walls warm up during warm weather, and  cause failure  or
puncture holes in the bottom of the tank.  Therefore,  water storage
tanks must be designed to prevent the growth of ice in the tank  under
all foreseeable circumstances, including unusual operating conditions,
and they should be completely drainable.  Because of  their vulnerability
to ice damage, interior appurtenances should be installed with caution.
         While it is usually easy to keep the stored water warm,  parti-
cular attention must be paid to the air space above the  free  water
surface.  The air in one Alaskan tank was 2.5C below  the water
temperature, but this will vary with the geometry, insulation and
outside temperatures [1],
         Since water is most dense at 4C, surface icing can  be
prevented by operating the tank at a temperature greater than 4C.
Continuous or intermittent circulation within the tank will also  help to
prevent density stratification and surface or wall icing.  The return
line of a recireulating water distribution system is  often discharged
into the storage tank.  This provides circulation and  temperature
control within the tank, and a large heat reservoir for  the system.

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                                 5-9
         Where practical, breather vents  should  be  located on the
interior of the tank, venting  into an attached  pumphouse or building
rather than to the outside where  ambient  temperatures  are low.  This
will prevent the vent from icing  up due to  condensation and will reduce
heat loss.  The vacuum  created  by a blocked vent when  the water level is
lowered can cause the tank to  collapse.
         Overflow piping should be designed so  that a  trickle flow does
not iee up and eventually block the pipe.   It  should be insulated and
heat traced if located  outside  the tank or  perhaps  run inside the tank
(Figure 5-1).
         Instrumentation should include a non-contact  water level
elevation (head) indicator,  sueh  as a pressure  transducer, since ice
would damage floats.  Temperature monitoring at  various levels for
control and alarms should be installed.
         Seasonal storage, e.g.,  where complete  winter storage is
required, can cause water quality changes,  such  as  reduced oxygen.
Chlorine residuals will also decrease with  time,  though less with colder
waters [2],  Because of the  effects of long-term storage on water
quality, treatment should occur after storage.
         Elevated tanks can  provide the necessary pressures in the
distribution system; however,  they can be a maintenance problem in cold
weather.  The large surface  area  and high winds  increase heat loss,  and
the standpipes must be  freeze-protected.  The  foundation must be
carefully designed.  In small  communities a pneumatic  system or constant
pressure pumps fed from a surface storage tank are  generally more
practical.
         Freezing of a  storage  tank will not usually occur all at once.
Layers of ice are formed over  several hours or days.  Periodic drawdowns
cause such layers or plugs to  become hung up and  separated by air gaps.
If this occurs, precautions must  be taken to prevent the piston action
of a falling ice layer.  Thawing  of an ice  layer  should be carried out
from the top.  The method and  sequence of thawing a particular tank  must
be designed into it and specified in operational  procedure manuals.
Extra equipment required must  be  supplied at the  time  of construction.

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                                  5-10
5.2.4    Thermal considerations
         The thermal characteristics of alternative designs  should  be
considered, although in many oases the size,  shape and  location  are
specified by other constraints.  Elevated  tanks expose  the greatest
surface area and must contend with low air  temperatures  and  high winds.
Tanks at the ground surface will lose less  heat and the  common vertical
cylinder shape is very near optimum, since  heat loss  to  the  ground  is
less than to the air.  Whenever practical,  tanks  should  be buried or
covered with soil to reduce the effect of  low air temperatures.
         All exposed surfaces should be insulated.  This is  particularly
important for steel tanks since the heat loss through exposed  steel,
where the only resistance is air film, will be at least  50 times that  of
a tank surface insulated with 50 mm of polystyrene.   Thermal breaks or
penetrations such as a ladder attached to  the tank exterior  must be
avoided or reduced.   The risers for elevated tanks must also  be
insulated.
         Exposure of inflow, outflow and circulation  piping  should  be
minimized, perhaps by using a common carrier  (e.g., pipe in  a  pipe).   A
common carrier also reduces the number of  connections into the tank,
which is of importance for lined tanks.
         The exterior surface could be painted a  dark colour to  absorb
as much incident radiant heat as possible  during  the  long dark winters.
         The economic thickness of insulation can be  determined  by
comparing the initial capital cost for increased  insulation  thickness
to the accompanying reduced heat loss, and  lower  annual  energy cost and
heating capacity requirements (see Section  15).   Other  considerations
such as a required maximum rate of heat loss  or temperature  drop over  a
specified period may require greater  than  this minimum  thickness.
Thermal calculations are also necessary to  size heating  systems  to  heat
water and to replace heat losses.  For storage tanks, piping and other
utility system components, the required capacity  is based on supplying
the maximum rate of heat loss, whereas the  total  energy consumption is
based on the annual heat loss.  The heating of water  in storage  tanks  by
the practical application of alternative energy sources, such  as wind

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                                   5-11
and low temperature waste  heat  from  electrical  generation,  should be
considered  (see  Section  14).
         Heat  loss can be  reduced  only  slightly by  operating  the tank
near freezing  since it is  the temperature  difference  that  determines
heat loss.  For  example, if  the ambient  temperature is  -20C  then there
will be a 12%  reduction  in heat loss  for a tank operated at 2C compared
to at 5C.  The  lower the  ambient  temperature,  the  less are the savings
by reducing the  tank temperature.  There are, however,  energy benefits
to operating near freezing where the  mean  air temperatures  are not much
below freezing,  and where  this eliminates  or reduces  the need to preheat
raw water supplies.
         Operation at over 4C will  prevent density stratification
and surface freezing, but  operating  at  over 10C is usually unneces-
sary and can result in vent  icing  problems.  The large  mass of water
reduces the potential for  freezing and  damage from  failures,  such as
prolonged stopages of heat input.  In any  case,  the tank should be
completely drainable.
         Small storage tanks may be  located within  a  building.   Some
innovative examples of this  are the  Kemi,  Finland,  multi-story city hall
which incorporates an elevated storage  tank, and the  British  Petroleum
camp near Prudhoe Bay and  several new schools in Alaska where the
swimming pool doubles as water storage  for  fire  protection.
5.2.5    Foundation
         Foundation considerations are  similar  to those for other
northern buildings, with the added concern of the high  weight of
water-filled storage tanks.  In non-permafrost  areas, normal  foundation
precautions should be considered, including those for frost heaving.  In
permafrost areas, active or  passive  design measures can be  used.  Active
measures include pre-thawing, excavation and replacement, and designing
for settlement.  Passive measures include  those  that  separate the tank
from the ground  and those  that maintain  the permafrost.  An example of
the former is the use of piles.  The  heavy loads  require close  spacing
of piles and a design analysis which  considers  the  creep of frozen
ground, particularly in  "warm" permafrost areas.  Examples  of the latter

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                                   5-12
are artificial refrigeration, thermal piles, and air ducts (with  or
without fans).
5.2.6    Costs
         Table 5-1 shows typical costs for water storage  tanks  in cold
regions.
5.3      Earth Reservoirs
5.3.1    General
         Water impoundments for domestic [3] and industrial water supply
[4] and dams  for hydro power generation [5] have been  successfully
constructed in the North.  Special design considerations  are  required in
permafrost areas, particularly in high ice content  soils  [6],
Construction  problems may include lack of specific  soils  required for
embankment construction, excavation and placement of frozen soils, and
other northern construction problems such as logistics and weather (see
Section 2).
         The  effective reservoir volume can be reduced substantially by
ice cover which can at times be 2 m thick.  The most critical years will
be those with low snowfall.  Ice thickness can be reduced to  a  limited
extent by using snow fences to create snow drifts,  thereby insulating
the surface.  Deep reservoirs can be used to minimize  surface area and
thus reduce the volume of frozen water.
5.3.2    Water quality
         The  quality of the water is influenced by  the soils  and  vegeta-
tion that it  comes into contact with.  Leaching from bog  soils  and
oxygen depletion during long periods of ice cover will necessitate water
treatment for colour, pH, taste and odour prior to  use.   These  effects
should be considered in preparing the bottom of the reservoir before
flooding [7].  Water quality is also affected by ice growth.  Thermal
stratification may influence the location of intakes.  It is  normally
desirable to  dyke the edges to prevent unwanted runoff from entering the
reservoir.  Signs, in appropriate languages, and fences are necessary to
deter access  to reservoirs by animals and unauthorized personnel.

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                                TABLE 5-1.   WATER STORAGE TANK COSTS
LOCATION
Ft. McPherson, NWT

Resolute Bay, NWT

Inuvik, NWT

Savoonga, Ak.

Shismaref, Ak.

Unalakleet, Ak.

Twin Hill, Ak.

Stebbins, Ak.

Grayling, Ak.
SIZE
3
450 m
3
450 m
3
2250 m

3
380 m
3
1140 m
3
3780 m
3
230 m
3
1900 m
3
230 m

Tank
Wood

Bolted Steel

Welded Steel

Welded Steel

Welded Steel

Welded Steel

Welded Steel

Welded Steel

Welded Steel
DESCRIPTION
Foundation
Piles

Insulated Pad

Piles

Pad

Pad

Pad

Pad

Pad

Pad


5

5

6.2

7.5

7.5

7.5

7.5

7.5

7.5

Insulation
cm polystyrene

cm polystyrene

cm polystyrene

cm polyurethane

cm polyurethane

cm polyurethane

cm polyurethane

cm polyurethane

cm polyurethane
COST (YEAR)
$166 000 (1975)

$190 000 (1976)

$750 000 (1976)
(estimated)
$106 000" (1977

$176 000- (1977

$308 000- (1977

$ 78 000* (1977

$212 000* (1977

$ 80 000* (1977
Does not include foundation.  Foundation costs in Alaska were $65 000 for a gravel pad or $170 000 for
piling with a floor system.

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                                 5-14
5.3.3    Dams
         Dams may be constructed to raise the Level of an existing  lake
or create a reservoir on a stream or river.  Overtopping is not
permissible; therefore, overflow structures must be provided.  Runoff at
spring breakup from northern watersheds tends to be very short and
violent, thereby increasing the size and complexity of the spillway.
Floating ice and wave action must be considered in large reservoirs.  The
force of ice bonded to dam structures can be significant when it  is
raised or lowered with the fluctuating water level.
5.3.4    Diked impoundments
         Dugout type, generally cut and fill, earth reservoirs may  be
periodically filled by pumping or by siphoning water  from a nearby
source.  This eliminates expensive overflow structures and simplifies
inflow and intake requirements.  The low head reduces seepage and
embankment stability design problems; however, the effective reservoir
volume is reduced by ice growth.  Groundwater seepage into a reservoir
can be a problem, and must be considered in the geotechnical investiga-
tion, even in permafrost areas, since sub-permafrost  or  intra-permafrost
groundwater may be encountered.  Impervious membranes have been  used
successfully in the central and eastern Arctic where  the native  soils
are generally permeable sands and gravels with some silt  [3],
         To reduce or eliminate excavation of frozen  soils, a reservoir
may be constructed by impounding embankments.  The higher head will
increase the importance of seepage control and embankment stability.
         The design of a dugout and diked  impoundment for a wastewater
lagoon is similar to a water  supply reservoir.
5.3.5    Impervious liners
         Many techniques and  types of natural and  synthetic  linings have
been used to reduce or prevent  seepage  from water  reservoirs  and
wastewater  ponds  [8],  In  cold  regions  where  impervious  soils  are not
readily  available, the thin  film synthetic  liners  have  been  popular,
although spray-on liners,  including polyurethane,  have  been  used to seal
petroleum product storage  tank  areas  [9],

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                                  5-15
          Impervious liners may be used within the embankment only, or to
 seal  the  entire  reservoir (Figure 5-6).  Folds may be left in the liner
 to  allow  for  settlement;  however, large differential settlements such as
 in  high ice-content soils should be avoided or designed with caution.
 Groundwater or  the  thawing of permafrost under the reservoir may create
 hydrostatic uplift  pressures or icing conditions.  These can be relieved
 by  underdrains,  well points or pressure relief valves.  The liner must
 be  adequately protected  from ice action to prevent punctures during
 installation  and operation (Figure 5-7).
          The  liner  material must be approved for the application, for
 example,  potable water, must be suitable for low temperatures and
 freeze-thaw conditions, and durable enough for shipping and installation
 [3,10],   The  ease of field seaming and repairing punctures is also
 important in  selecting a  liner system.  There are numerous liner
 materials available but few are suitable for the rigorous installation
 and operating conditions  associated with cold regions.  Thin plastic
 films  (4,  8 and  10  mil polyethylene and PVC) have failed at heat-sealed
 joints.   Exposed portions were punctured by the gravel base and ripped
 by  falling ice as the water level lowered.   If adequately bedded and
 covered,  weak films as thin as 10 mil can perform satisfactorily but
 even the  most suitable material must be installed properly and  with
 care.  Membranes  of  high puncture strength and elasticity will require
 less intensive bedding preparation and installation restrictions than
 more fragile  ones.   Successfully used liner materials include hypalon
 synthetic  rubber, chlorinated  polyethylene  (CPE), and Dupont 3110
 elasticized polyolefin.
         Manufacturers and  suppliers must be made aware of the
 anticipated installation  and  operating conditions.   New materials or
 requirements  should be laboratory tested under extreme conditions such
 as those  outlined by Foster  et al  [3],
 5.3.6    Foundations and  thermal  considerations  in  permafrost areas
         Impounded  bodies of water  disturb  the  natural  ground thermal
 regime.   In permafrost areas,  a  permanent  thaw bulb is  created  beneath
water bodies  that do not  freeze  to  the  bottom.   In  ice-rich soils this
 thawing may cause structural and  seepage problems for the  reservoir  and

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                                   5-17
the containing  embankments  or  dam.   The  structural problems are essen-
tially  two-fold.   Firstly,  the thaw-consolidation of underlying ice-rich
soils creates differential  settlement, and  secondly, excess pore-water
pressure generated in  fine-grained  soils as the  thaw front advances can
cause failure.
         Foundations and  thermal  consideration provide the main design
problems.   The  main construction  problems are  availability of soils and
excavation  and  placement  of frozen  soils.
         The thermal regime and,  in particular,  the thaw boundaries can
be estimated by two and  three-dimensional analysis and the settlement
calculated  from the soil  and temperature conditions [6],  The most
sensitive area  with regard  to  stability  is  under or adjacent to the toe
of the  upstream slope.   Some differential movement may be tolerated in
low head dams as  long  as  the overall stability and seepage control are
adequate.
         Seepage  reduction  or  elimination is important in the thermal
design  as well  as  the  functional  design.  In the former case, sensible
heat transport  by  seepage will result in embankment temperatures only
slightly lower  than that  of the reservoir water  [5], This will promote
deep thawing under the embankment with its  associated  problems.  Icing
will occur  at the  toe  of  seeping  embankments.
         Passive  foundation designs are  based  on preventing the embank-
ment from thawing.  Thawing under the reservoir  is inevitable and would
be impractical  to  arrest.   In  very  cold  regions  with a shallow active
layer,  the  permafrost  may rise in the embankment resulting in a natural
impervious  frozen  core [11].   In warmer  regions, hydrophobic insulation
and/or  cooling  may be  necessary to  maintain a  frozen core and
foundation.  Vertical  air ducts with natural draft or  blowers to induce
winter  air  circulation and  refrigeration  have  been used in dam
construction.   These measures  have  high  capital  and operating costs,  but
may be  necessary for high embankments on  thawing ice-rich soils.
          Active designs  allow thawing but  any resulting settlement or
instability is  considered.   Such "thawed" designs  are  necessary in the
discontinuous permafrost  zone.  Measures  to decrease the total thaw or
rate of thawing may be required.  Settlement can be reduced by natural

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                                 5-18
or artificial pre-thawing or excavation of the high ice content

near-surface organic and soil layers.  These expensive measures may be
limited to the embankment foundation and selected areas.  Where

differential settlement is expected, self-healing semi-impervious
embankment material, such as sand, should be used, although  this allows
seepage which will promote thawing.  Maintenance approaching  rebuilding
may be required in the first few years [12],

5.4      References

1.  Cohen, J.B.  and Benson, B.E.  "Arctic Water Storage", Journal
       American Water Works Association, j>0_(3) :291-297, 1968.

2.  Nehlsen, W.R. and Traffalis, J.J. "Persistanoe of Chlorine Residuals
       in Stored Ice and Water", U.S. Naval Civil Engineering Research
       and Engineering Laboratory, Port Hueneme, California,  Technical
       Note N-206, 1954.

3.  Foster, R.R., Parent, T.J. and Sorokowski, R.A.  "The Eskimo Point
       Water Supply Program", In:  Utilities Delivery in Arctic Regions,
       Environment Canada, Environmental Protection Service,  Report No.
       EPS 3-WP-77-1, Ottawa, Ontario, 1977.

4.  Rice E.F. and Simoni O.W.  "The Hess Creek Dam", In:  Proceedings,
       Permafrost International Conference, Lafayette, Indiana, 1963,
       National Academy of Science, Washington, D.C. pp. 436-439, 1966.

5.  Brown, W.G. and Johnston, G.H.  "Dykes in Permafrost:  Predicting
       Thaw and Settlement", Canadian Geotechnical Journal, _7(4): 365-371,
       1970.

6.  National Research Council of Canada,  "Permafrost Engineering
       Manual - 1 Design and Construction", National Research Council of
       Canada, Ottawa, in preparation.

7.  Smith, D.W. and Justice, S.R. "Effects of Reservoir Clearing on Water
       Quality in the Arctic and Subarctic", Institute of Water
       Resources, University of Alaska, Fairbanks, Alaska, IWR-58, 1975.

8.  Middlebrooks, E., Perman, C.D. and Dunn, I.S.  "Wastewater
       Stabilization Pond Liners", U.S. Army, Cold Regions Research and
       Engineering Laboratory, Hanover, New Hampshire, In preparation.

9.  EBA Engineering Consultants Ltd.  "A Study of Spray-on Liners for
       Petroleum Product Storage Areas in the North", Environmental
       Impact Control Directorate, Environmental Protection Service,
       Environment Canada, Report No. EPS 4-EC-77-2, Ottawa,  Ontario
       1977.

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                                 5-19
10. Thornton, D.E. and Blackall, P.  "Field Evaluation of Plastic Film
       Liners for Petroleum Storage Areas in the Mackenzie Delta".
       Environmental Conservation Directorate, Environmental Protection
       Service, Environment Canada, Report No. EPS 3-EC-76-13, Ottawa,
       1976.

11. Fulwider, C.W. "Thermal Regime of an Arctic Earthfill Dam", In:
       North American Contribution PERMAFROST Second International
       Conference, 13-28 July, 1973, Yakutsk, U.S.S.R., National Academy
       of Science, Washington, D.C. p. 662-628, 1973.

12. Cameron, J.J. "Waste Impounding Embankments in Permafrost REgions:
       The Sewage Lagon Embankment, Inuvik, N.W.T.", In:  Some Problems
       of Solid and Liquid Waste Disposal in the Northern Environment,
       Slupsky J.W. (ed), Environmental Protection Service, Environment
       Canada, Edmonton, Alberta, EPS-4-NW-76-2, pp. 141-230, 1976.
5.5      Bibliography

    Alter, A.J. and Cohen, J.B.  "Cold Region Water Storage Practice",
    Public Works Magazine, October, 1969.

    Branch, J.R.  "Evaluated Water Tank Freeze-up:  A Freeze-up
    Experience", Journal American Water Works Association, 60(3);291-297,
    1967.

    Shoblon, G. and Oliver, R.H.  "An Evaluation of Foamed Polyurethane
    for Containment Dike Liners".  A report prepared for the Technical
    Committee on Petroleum Dyking in the North, G. Shoblom and R.H.
    Oliver, Cominco Ltd., Trail, British Columbia, 1976.

    Eaton, E.R.  "Floating Plastic Reservoir Covers in the Arctic", Solar
    Energy. _8(4):116, 1964.

    Foster, R.R.  "Arctic Water Supply", Water and Pollution Control,
    _3(3):24-28, 33, March, 1975.

    Larson, L.A.  "Cold-weather Operation of Elevated Tanks", Journal of
    American Water Works Association, 68(1):17-18, 1976.

    Toman, G.J.  "Elevated Water Storage Tank Freeze-ups:  Correction of
    Freeze-ups", Journal American Water Works Association, 59(2);166-168,
    February, 1967.

    Wormald, L.W.  "Water Storage Tank Failure Due to Freezing and
    Pressurization", American Water Works Association Journal,
    64(3):173-175, March, 1972.

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                                SECTION 6
                           WATER DISTRIBUTION
                                  Index
                                                                    Page
6        WATER DISTRIBUTION                                         6-1
6.1      Introduction                                               6-1
6.2      General Assumptions and Design Considerations              6-1
6.3      Self-Haul Systems                                          6-3
6.3.1    Watering point design                                      6-3
6.3.2    Types of systems                                           6-4
6.4      Community-Wide Haul Systems                                6-5
6.4.1    Water loading point design                                 6-6
6.4.2    Vehicle sizing and design                                  6-11
6.4.3    Ice haul                                                   6-16
6.5      Piped Systems                                              6-17
6.5.1    Above or below-ground                                      6-18
6.5.2    Types of systems                                           6-18
6.5.3    Other methods                                              6-26
6.6      Service Lines                                              6-28
6.6.1    Method of circulation                                      6-28
6.6.2    Materials                                                  6-30
6.6.3    Dual servicing                                             6-30
6.7      Materials of Construction                                  6-33
6.7.1    Category 1 materials                                       6-34
6.7.2    Category 2 materials                                       6-35
6.7.3    Other types of pipe used                                   6-37
6.7.4    Miscellaneous fittings                                     6-37
6.7.5    Insulation                                                 6-38
6.8      Appurtenances                                              6-38
6.8.1    Hydrants                                                   6-38
6.8.2    Valves                                                     6-40
6.8.3    Metering                                                   6-40
6.8.4    Manholes                                                   6-42
6.8.5    Alarms and safeguards                                      6-45

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                               Index (Cont'd)
                                                                    Page
6.9      Backup Freeze Protection Mechanisms                        6-45
6.9.1    Heat trace systems                                         6-45
6.9.2    Thaw wire electric resistance systems                      6-46
6.9.3    Steam or hot water thawing                                 6-46
6.9.4    Freeze damage prevention                                   6-47
6.10     References                                                 6-47
6.11     Bibliography                                               6-48

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                             List of Figures
Figure                                                              Page
 6-1     Self-Haul Watering Point (Greenland)                       6-3
 6-2     Overhead Truck Fill Point                                  6-7
 6-3     Water Truck Fill Point (Greenland)                         6-7
 6-4     Water Truck Fill Point with Hose Nozzle Fill               6-8
 6-5     Bottom Fill Point                                          6-9
 6-6     Truck with Flotation Tires for Traction in Snow            6-13
 6-7     2225-Litre Water Trailer                                   6-13
 6-8     Water Delivery Truck Tank Body Piping and Equipment
         Diagram                                                    6-15
 6-9     Tracked Vehicle Used for Ice haul                          6-17
 6-10    Layout and Location of Mains for Single-Pipe
         Recirculation                                              6-20
 6-11    Single-Pipe System without Recirculation                   6-22
 6-12    Typical Utilidor and Packaged Preinsulated Pipe            6-23
 6-13    Dual Pipe System                                           6-24
 6-14    Dual Main Sub-System                                       6-25
 6-15    Small Diameter Water Mains                                 6-27
 6-16    Flushing Hydrant System                                    6-29
 6-17    Water Service Line                                         6-31
 6-18    Above-ground Service Line                                  6-31
 6-19    Above-ground Service Line Take-offs                        6-32
 6-20    Underground Valve and Box                                  6-32
 6-21    Dual Servicing                                             6-33
 6-22    Supported Pipe Take-offs                                   6-35
 6-23    Above-ground Hydrant           i                            6-39
 6-24    Below-ground Hydrant                                       6-41
 6-25    Mini Service-centre Manhole                                6-43

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                                      6-1
6         WATER DISTRIBUTION
6.1       Introduction
          Throughout this section the various methods of distributing
water from source to user will be discussed in the following categories:
General:      a general discussion on why or when the particular system
              is applicable and suitable to a given northern situation.
Objectives:   the objectives that should be achieved when designing the
              particular system for northern conditions.
Existing Systems:  descriptions of systems that have or have not worked.
          Water distribution is carried out in three main ways.  These
are self-haul, community-wide haul (trucked water or ice) and piped
systems.  The system which should be used in any given situation depends
on a number of factors:
          - governmental policy,
          - population,
          - geographic and physical site location conditions,
          - economic base of community,
          - health standards,
          - available technical skills,
          - ability and willingness of community to operate and maintain
            the facilities.
          Given the factors involved for a particular northern community,
a detailed economic analysis must be carried out to determine which is
the most appropriate system for that community.
          In the Northwest Territories, general terms of refrence  [1]
have been prepared for use in carrying out the economic analysis.
6.2       General Assumptions and Design Considerations
          Average residential consumption of water in areas serviced by a
trucked water delivery and sewage collection systems is generally 95 I/
person/day for a four person household with conventional plumbing.
Water conservation fixtures (e.g., low water use toilets) can reduce
consumption and should be a necessary part of future building design for
most northern communities.

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                                  6-2
         Present consumption in houses without  plumbing  is  less  than
20 L/person/day.  However, concurrent with the  gradual  improvement  of
housing in the North will be a gradual increase  in  per  person  consumption
of water.  Residential areas serviced by a piped water  delivery  system and
trucked sewage collection system will have an average water demand  of  140
L/person/day immediately.   Communities totally serviced  by a  piped water
distribution and sewage collection system will  have an  average water demand
of 450 L/person/day, including industrial uses.  The average residential
water demand will be 270 L/person/day.
         For communities with a poor road system it is  not  practical  to
design water and sewage trucks to carry greater than 4550 litres per load.
         Building water and sewage tanks should be  sized  for a minimum of
five and seven days capacity, respectively.
         Community population projections are available from the
appropriate government departments:  in the  Northwest Territories and  the
Yukon, the Department of Local Government; and  in Alaska, the  Department
of Community and Regional Affairs.  These projections should be  utilized
in planning community systems.
         Fire protection requirements for system designs incorporating
full fire protection capability or otherwise are noted  in Section 12.
6.3      Self-Haul Systems
         The self-haul system has limited application and a number of
drawbacks which often make  it undesirable for water distribution.
         In northern Canada this mode is practiced  mainly in small unin-
corporated settlements of 50 people or less  where no mechanization yet
exists, e.g., the people obtain their water  from a  nearby lake or river
and haul it to  their house.
         As the community grows, the  increased  population density often
results in sewage contamination of the drinking water  source and the  need
to provide central water  points where people can pick  up safe  chlorinated
water.  These watering points are usually only  installed when  the community
doesn't have  the necessary  infrastructure,  i.e., roads, holding  tanks  for
water  in houses with exterior fill points,  sewage  pump-out tanks, etc.,
to accept a trucked water and sewage  system.

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                                  6-3
         The trucked water system is preferred where  possible  over  a
central pick-up watering point.  The reasons for  this are:
         - more positive means of supplying housing units on regular
           basis with clean safe water,
         - allows increased water usage and thus  better  hygiene,
         - housing units with pressure systems can eventually  be  hooked
           onto piped systems with minimum problems,
         - unsupervised watering points tend to be vandalized  and become
           both unsanitary and quickly nonoperational.
6.3.1    Watering point design
         Watering points (see Figure 6-1) are usually operated in
conjunction with some other form of water distribution or supply
system.  They are often located in older parts of a community  where the
houses are not equipped for a trucked or piped system.   In Alaska they
are constructed as an interim solution to provide safe drinking water
until distribution of some sort is feasible.
            FIGURE 6-1.  SELF-HAUL WATERING POINT  (Greenland)

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                                  6-4
         The failure rate of the self-haul watering  point  is  very great.
Almost six out of 10 are nonoperational after one  year.  This is  mainly
due to vandalism, freeze-ups, poor design, and  lack  of  supervision and
management.  Because of these problems the water points  are usually
abandoned and not repaired.
         Objectives of the ideal self-haul watering  point  are:
         - maximum cleanliness and sanitation in getting water  to the
           container,
         - minimum maintenance,
         - material design to minimize vandalism.
6.3.2    Types of systems
6.3.3.1  Exterior unsupervised.  This is  a small heated  building  con-
taining a water  tank, water  piping and valves.  The  user either pulls a
chain from outside the building or pushes an electrical  button  activating
a solenoid valve which releases water through a spout  into his  container.
When he releases the button  the valve closes and the remaining  water in
the line drains  out the spout.  A similar mechanical spring-loaded lever
can also be used.  A suitable splash base of gravel  and  rocks or  slotted
boards is required below the spout.  A hanger for  the  water  container is
also normally provided.  The exterior of  the building  must be made as
vandal-proof as  possible.  Native logs or heavy duty siding  is  preferable
to normal "metal type" siding.  Concrete  block  would also  be  ideal if
feasible for the location.   The entrance  door is kept  locked  and  only the
maintenance man  should have  access.
         The tank could be filled by truck from the  outside,  and  again
access to the inside would be prohibited. A light outside would  indicate
that the tank is full.  Failure to stop  filling when the light oomes on
would result in  the tank overflowing outside  through a vent pipe.
Usually two lights are used  in case one  burns out, which is also  an
indication for  the maintenance man to replace it.   Similar on-line
systems in conjunction with  water distribution  mains are also used.
6.3.3.2  Interior watering points must be supervised.   Otherwise, the
door to building will be left open, and  the  system will either freeze up
or be vandalized.

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                                  6-5
6.3.3.3  Central facilities are discussed  in detail  in  Section  11.
6.3.4.4  Containers.  The  type of container recommeded  is  a  20  L
enclosed plastic "camper"  type water container  to minimize contamination.
What is used in practise is anything that  will  hold  water, usually  an
open water pail.
6.4      Community-Wide Haul Systems
         Community-wide haul systems are  those  systems  which transport
water from a water or ice  source or watering point  to a fill point  at  the
individual houses.  This is usually accomplished using  a tracked,  towed
or wheeled vehicle.
         The "truck" or vehicle-delivery  system is  used in all  or
portions of most communities in northern  Canada where the  population
ranges from 50 to 1500.  Generally, it  becomes  more economic to pipe
water when the population  reaches a range  between 600 and  1,000 people,
depending on the location  and  conditions.  At  this  point a dual system of
both trucked and piped water continues  until the existing  areas are put
on piped service.  In Alaska the truck-haul  system  has  been  found
expensive to operate and maintain.  Piped  delivery  systems and/or  central
pick-up is preferred in most cases.  However;  circumstances  in  each
community must be considered on an  individual  basis. No subsidy is
offered for operation of water delivery systems in  Alaska.
         In a nonpiped community, the water  loading point  for the  veh-
icles is usually a prefabricated building  on the shore  of  a  lake or river,
or beside a well.  Vehicle system costs can  be  reduced  at  some  communities
by construction of a water supply pipeline from a distant  water source.
6.4.1    Water loading point design
         Objectives for  the design  of the  water loading point are:
         - maximum cleanliness and  sanitation,
         - minimum spillage and subsequent freezing and ice  buildup
           around the water point,
         - efficient truck entry and exit  routes taking into considera-
           tion prevailing winds and snow drifting,
         - minimum maintenance requirements.

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                                  6-6
There are four types of  systems used:
         - overhead pipe  loading,
         - hose nozzle fill,
         - bottom  loading,
         - interior building  fill  point.
6.4.1.1  Overhead  pipe filling system.  Figures  6-2  and 6-3 show
typical overhead systems.   Included  in  such  a  system would be an exterior
key start switch for the  water pump.  Often  the  water delivery is done by
a private contractor, and  only the contractor  is given the key.  All
water pumped out is registered on  a  meter  inside the building.  Access to
the inside of  the  building  is limited to maintenance personnel.
         The loading arm  drains in two  directions after each filling.
From the high  point it drains back to the  heated building and from the
spout into the truck.  Thus  freezing is prevented when the fill point is
not in use.
         A swivel  type elbow allows  the loading  arm  to swing away if hit
by a vehicle.  This often happens  in the winter  when the snow and ice
builds up so that  the top of the  truck  is  close  to touching the fill pipe
         A major problem with this type of fill  design is that,
invariably,  the key gets  turned off  when  the truck tank is overflowing.
This leads to  ice  buildup on the  ground which  makes  it hard for the truck
to park and  often  is the  cause of  the building siding being damaged by
the vehicle.   Guard rails should  be  used  to  protect  the building, and the
water fill pipe should be located  such  that  the  downspout is far enough
away from the  building and high enough  off the ground to compensate for
seasonal snow  and  ice buildup.  To prevent splashing during filling and
to compensate  for  the  seasonal variation  in  height,  flexible low
temperature  rubber hose  should be  connected to  the  bottom of  the
downspout, as  shown in Figure 6-3.
6.4.1.2  Hose  nozzle filling system  (Figure  6-4).  In an effort to
prevent  spillage and  ice buildup,  a  fill  point using a gas tank fill
hose nozzle  has been used.  The  truck drives by a wooden platform, a
small door in  the  loading point building is  opened,  and a hose nozzle is

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      75 Swivel elbow
 6-7

kamlock' quick coupler -
                             Low temperature
                             rubber hose
         w^/^Mm^/j^/^0^mfl

    FIGURE 6-2.   OVERHEAD TRUCK FILL POINT
FIGURE 6-3.  WATER TRUCK FILL POINT  (Greenland)

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                                   6-8
                         Water distribution pumphouse
                                      00 \.\\\  //// 00
        FIGURE 6-4.  WATER  TRUCK FILL POINT WITH HOSE NOZZLE FILL
pulled out through roller guides.   A platform is provided such that the
driver can take out  the  hose  nozzle,  put  it in the top of the truck, and
then turn on the key start.   The nozzle is designed to turn off under
back pressure.  However, more often than  not it is thrown in the open top
hatch of the truck locked in  the open position.  When the driver sees the
tank is full he turns  the key off  and puts the hose back in the cabinet.
The hose is such that  it is long enough to reach the truck but not long
enough that it could touch  the ground.
         While this  design  does not totally eliminate water spillage
because of misuse, it  has greatly  reduced the amount of spillage compared
to the overhead fill pipe.  There  is  some spillage when the driver pulls
the hose out of the  tank and  puts  it  back in the building.
6.4.1.3  Bottom filling  system (Figure  6-5).  The third type of system
utilizes an aircraft refueling technique.  A bottom liquid loading device
as shown in Figure 6-5 is provided and  the truck is filled through the
water source suction inlet  at the  back  of the tank.

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                       Water meter
 Flow control valve
                                   75 0 Bottom liquid loading devi<
                                   mounted on tee flange with 75 6
                                   Kamvalok dry disconnect coupli
Water
supply
     3000
                                                                Elevation   B-B
                            300
            ;>v/.^:^~Yv~i'.:V; vVrrf 15 M at 250 E.W.
                                          _ 900 mm sq.
                                          concrete block
Three way valve 
                    120 L Solution tank with
                    chlorinator
                     Unit heater

                          Flow control valve
              Storage for calcium hypochlorite drums
                                                     Unit
                                                     heater
                                  B
                                                                     100 mm Thick insulate
                                                                     floor, wall, and roof
                                                                     panels and doors
                                                  Truck
                                                  loading zone
                                                                            \  \
                                                                            \ \
                                                                             \>
                                              Water meter
                              FIGURE 6-5.  BOTTOM FILL POINT

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                                 6-10
         Again, the filling  point is  separately  housed  with access for
maintenance.
         To prevent overfilling  the truck a  batch  meter is  provided that
can be set by the  truck driver for the  tank  capacity of the truck.  The
bottom loader is swung out,  connected  to the  back  of the truck via a
quick connect coupling, the  volume desired punched in on the batch meter,
and the pump turned on using key start.  The  meter shuts off the pump
when the preset amount is  reached, the  loader arm  is disconnected and
swung back into the compartment, and  the door is shut.   The quick connect
coupling between the loading arm and  the truck is  spring loaded so that
it closes on disconnection and only a  small  amount of water is
spilled.
6.4.1.4  Interior  fill points.   These  consist of watering points
similar to the overhead type except that the  fill  point is  inside the
water truck garage.  This  is usually  only used when the community size is
small, 200 - 300 population, and the  loading  frequency is only once or
twice per day.
         All new truck filling points  in northern  Canada are designed to
provide a minimum  loading  rate of 450  L per  minute with a desireable rate
of 700 L per minute.  The  basis  for the minimum  filling rate is two-fold.
Firstly and most important fire  trucks  in an  emergency must be refilled
as quickly as possible.  The Fire Marshal has set  a minimum rate of 450 L
per minute or 10 minutes to  fill a 4500 L tank.  The second reason is
economic, i.e., the quicker  the  fill  rate, the less chance  the operator
will sit in the cab and forget about  the truck filling, and the shorter
the turn around time.
         The truck filling points should be  well-lighted because in many
areas there is total darkness  in the  winter  and  the truck's parking
position is critical no matter what the filling  system.
         The truck should  be able to  drive  past  the loading point where
at all possible.   Backing  up requires more  time  and often results in
minor accidents which damage a building or  support structure.  Snow
removal is also easier.  The road should be  built  up higher than the
surrounding tundra and  in  line with the prevailing winds, to keep snow
from building up in front  of the loading point.

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                                 6-11
         Where piped systems are available in a community  the  water  truck
usually obtains water from the firehall or other  suitable  building  that
has piped water service and appropriate connections  for  filling  the
truck.  Often the water truck and  the  fire truck  are stored  in the  same
building and the filling point is  inside  the garage.
6.4.2    Vehicle sizing and design
         Water and sewage pump-out trucks are designed  so  that the  holding
tanks and filling or suction mechanism can be housed on  a  standard  truck
chassis. This is also true of sewage pump-out vehicles.
         The costs for wheeled and tracked water  delivery  vehicles  in
1976 dollars are:
         4450 L insulated tank unit                     $16 000
         Cab and chassis, wheeled  vehicle                10 OOP
         Total Capital Cost                             $26 000
         Tracked vehicle                                $26 000
         2225 L tank unit                                16 OOP
         Total Capital Cost                             $42 000
         Use of tracked vehicles is discouraged as much  as possible
because of their:
         - high initial cost,
         - high annual maintenance costs  and difficulty  in obtaining
           parts,
         - short life expectancy,
         - lower payload,
         - slower speed and longer travel time  from  water
           source to houses and back to water source.
Tracked vehicles are only recommended  for those communities  where there
are no roads or where it is impossible to get to  the water source in
anything other than a tracked vehicle. An example of this would be  a  source
of water close to the community with road access  only in the summer.  In
this situation a pipeline from the source becomes very attractive because of
the high cost of operating the slow tracked vehicles.

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                                     6-12
          There are very few communities in northern Canada that still
use a tracked water vehicle.  It has been found that in normal snow and
winter conditions a wheeled vehicle can adequately do the job.  In areas
where very heavy snow and snow drifting conditions are experienced,
wheeled vehicles with four-wheel drive and large floatation tires are
being utilized with success (see Figure 6-6).
6.4.2.1   Truck and tank sizes.  Larger tanks reduce the number of trips
to the water source.  However, they are heavier and require larger
vehicles.  Often, the condition of the roads in the community and to the
water source, access to buildings and other local conditions will dictate
the practical maximum size of tanks and vehicles.  In very small
communities, truck tank units of 2225 L capacity are usually adequate.
However, 4550 L units are now being ordered even for these communities
since the cost difference between the two is small.  Where roads and
community infrastructure are still rudimentary (no mechanics, etc.), 2225
L water trailer units are being purchased rather than wheeled or tracked
vehicles with the tank assembly mounted on the chassis.  These units are
in all aspects the same as those mounted on truck chassis, except that
they are towed by a farm tractor or other suitable vehicle (see Figure
6-7).
          The number of vehicles required depends primarily upon the total
community consumption, distance to the water source, the vehicle
characteristics and the efficiency of operation.  Equations to estimate
the requirements and costs are presented in Appendix D.  For typical
operations with little or no distance to the source and a water
consumption  rate of 90 L/person/day, one 4550-L water truck can service a
population of approximately 250.  If consumption was only 10 L/person/day,
it could service 1000 persons.  If the source was 3.25 km away, the
number of persons served would be 160 and 850, respectively.
          In the Northwest Territories, the truck tank capacities to date
have largely been sized and directly influenced by the low water
consumption  due to a lack of plumbing.  Public housing provided only
rudimentary  domestic plumbing  systems:  a small water holding tank
(approximately 450 L), a sink  and direct drain pipe to the outside, and a
honey bucket.  With this arrangement water consumption is usually about

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                          6-13
                        >*             
FIGURE 6-6.  TRUCK WITH FLOTATION TIRES  FOR  TRACTION IN SNOW
            FIGURE 6-7.  2225-LITRE WATER  TRAILER

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                                     6-14
10 - 20 L/person/day.  The public housing in the NWT now provides full
plumbing, pressurized systems with 1140 L water holding tanks, and 1140 L
sewage pump-out tanks.  In these houses it is expected that water
consumption will reach 95 L/person/day, as is experienced in four-person
homes with full conventional plumbing on trucked systems in Yellowknife,
NWT.  Water conservation measures can reduce this demand.
          Since truck system costs are directly proportional to the
consumption, they will become more expensive to operate as the residential
and non-residential water demand increases with higher populations and/or
higher standards of housing and plumbing.  At some point, it will become
more economical to install a piped supply line and/or distribution system
since these costs are less sensitive to the capacity requirements.  A
complete evaluation of any given system can be made using the rationale and
equations given in Appendix F.
6.4.2.2   Vehicle design.  Over the years water delivery vehicles and
sewage pump-out vehicles have continually been modified and improved to
meet the needs of northern conditions.
          Truck tanks for northern use must be insulated and all working
systems protected from freezing (see Figure 6-8).
          Vehicle specifications which reflect the state of trucked delivery
design at this time can be obtained form the Department of Public Works,
Government of the N.W.T., Yellowknife, N.W.T., Canada, and the U.S. Indian
Helath Service, OEH,  Box 7-741, Anchorage, Alaska 99510.
          The sewage  pump-out vehicle uses a pressure vessel and vacuum
pump system to evacuate holding tanks.  The inherent maintenance problems
associated with fluid passing through a pump are thus eliminated.
          A prototype using this concept is being developed and tested by
private  industry for  water delivery.  For water vehicles using the pressure
vacuum system the action is the reverse of a sewage vehicle,  i.e., the tank
is  pressurized to force the liquid out.  Such a  system has a high flow rate
and may  have sufficient water flow and pressure  to meet  the unerwriter's
requirements for fire trucks as well as water delivery vehicles.  Advantages
of  this  system include elimination of  the problems of pump maintenance and
freezing.   In addition,  such a water delivery vehicle can be  easily
converted to a sewage pump-out truck.

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        FIGURE 6-8.  WATER DELIVERY TRUCK TANK BODY PIPING AND  EQUIPMENT DIAGRAM

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                                 6-16
6.4.3    Ice haul
         Ice as a water  source and community  ice  haul  as  a  means  of water
distribution is carried  out only where no  other normal water  source is
available.  For example, in arctic Canada  only one  community,  Grise
Fiord, still uses ice as a winter water  source via  icebergs locked  in the
sea.  In Alaska there are still a few communities,  such as  Barrow,  that
use ice to supplement the normal water supply.
         In numerous other communities ice is used  as  a winter water
source because of individual choice and  preference.  That is,  some  local
people in certain communities prefer the taste of water obtained  from ice
to that of the delivered chlorinated water which  is  obtained  from usually
small lakes.  The taste  of water from such lakes  is  affected  by lack of
oxygen after prolonged ice and snow cover  in  the  winter and presence of
organics.  Ice obtained  in this case is  usually on  an  individual  basis
and not supported or organized by the community.
         The inherent high degree of labour and handling  involved in
harvesting ice increases the possibility of contamination.   Any system of
ice harvesting should minimize labour involvement as well as  possible
sources of contamination in all phases of  the operation,  including
harvesting, storage and  distribution.
         When ice is harvested from icebergs, as  is the case  in Grise
Fiord, Canada, the distance from the shore to the bergs could be  as much
as 8 km.  Tracked vehicles are required  to traverse the sea ice and
pressure ridges (see Figure 6-9).
         Tracked vehicles with flat bed  open  boxes  are used to harvest
and distribute ice in winter.  In the summer  the  box is removed and a
water tank with a pumping attachment is  fitted  to the  tracked vehicle.
         The ice is cut  with chain  saws  or axes.  Electric chain saws
powered from the tracked vehicles are recommended to avoid contamination.
This operation is usually done by two men.
         The ice is brought back and, if not  distributed  immediately, is
stored in an unheated parking garage to  prevent contamination.  The ice
delivered to each household is placed in the  water  holding tank to  melt.

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                                 6-17
             FIGURE 6-9.  TRACKED VEHICLE USED FOR  ICE  HAUL
                          (Grise Fiord, N.W.T)
         Grise Fiord has a population of 94 and  the  annual operating
cost of harvesting ice is $36 000.  Because of the  high cost  and  severe
water restrictions in winter, plus the possible  health  hazard due  to
contamination, such systems are replaced as soon as  economic  alternatives
are developed.
6.5      Piped Systems
         As discussed earlier, piping systems are used  because  they are
the most efficient, safe and economical means of distributing potable
water given a population of usually greater than 1000 people.  Alaska,
however, has piped systems in communities considerably  smaller  than 1000
population.  The point at which piping systems become more economical
than trucked systems must be determined for each individual community
with its unique characteristics (see Reference [1]).
         The systems outlined below describe the basic  operation  and
antifreeze mechanisms.  Backup mechanisms will be discussed under  a
separate heading.
         Northern piping systems should be designed  to:
         - minimize energy input for operation,
         - be simple to operate and maintain,

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                                 6-18
         - be protected against mechanical damage, vandalism and severe
           climatic conditions,
         - have a prime antifreeze mechanism with at least one backup
           mechanism, if not two,
         - be drainable,
         - have a minimum 40-year design life,
         - provide easy isolation of sections and service lines at any
           time of the year,
         - minimize on-site labour and,
         - allow maximum use of the short construction season.
6.5.1    Above or below-ground
         Whether the piping system is placed above or below-ground will
depend on the particular site conditions of a given location.  Generally,
below-ground systems are preferred where at all possible.  The criteria
for selection of above or below-ground systems are presented in Section  2.
         Piping systems are described later in this section do not differ
in operation whether the system is above or below-ground.  Only appur-
tenances of the system vary.
         Above-ground systems have been used where ground conditions and
thaw do not permit the use of a buried system with any degree of success.
However, with the advent of more efficient insulating material, these
conditions are becoming less significant factors in choosing between
above and below-ground systems.  Above-ground systems are becoming
economical only where ground conditions are very rocky.
         In areas where there is no permafrost, pipes can be buried below
seasonal frost penetration.  However, this may be impractical or very
expensive due to deep frost or excavation through rock.  An analysis
should be carried out to determine whether a shallow buried, insulated
pipe would be more economical and less of a maintenance  problem than a
deep buried pipe.
6.5.2    Types of systems
6.5.2.1  Single-pipe recirculation.  The single-pipe recirculation
system, whether above or below ground, is recommended as the best piping

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                                     6-19
system for arctic conditions.   This system consists of one or more
uninterrupted loops originating at a recirculating facility and returning
to that facility without any branch loops.
          A well-planned recirculating system minimizes the length of
piping required which, in turn, minimizes energy losses.  Recirculation
eliminates dead ends and any possibility of stagnant water or freezing.
          The system also allows positive simple control of water distribu-
tion.  Flow and temperature indicators on the return lines at the central
facility are all that is required.  Under constant pumping the pretemper-
ing requirement is controlled by the supply and return temperatures.
Normally water is pumped out at between 4-7C and returns at between
1-4C, depending on local preference.  In Greenland, temperatures are
held at 1C, and down to 0.1C return with electric heat tracing
and better sensing devices.  However, this leaves a very low margin of
safety for repairs and is not recommended.
          The obvious disadvantage is that, as the length of the loop
increases, the loss of service increases in case of a shutdown due to a
problem anywhere along the line.  In practice this usually is not a
problem as the loop is extened annually to meet the normal growth rate
of the community, and at the completion of each phase, temporary short
loop links are installed to complete the loop that given year.  The
following year these links are abandoned, valved off and the pipe left
empty.  In the case of an emergency these abandoned links can be opened
up to reroute the flow of water and possible isolate the break.  This
problem is also easily overcome on a short-term basis by bleeding at
appropriate points, especially when combined "mini service-centre
manholes" are used.
          The single-pipe recirculation system is usually designed to
supply water in the normal "return" line as well as the supply line under
fire conditions.  For this reason the return line does not decrease
drastically in size.  A typical pipe size would be 250 mm out and 200   mm
return for a design community population of 2000population.

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                                      6-20
               The recirculating facility could be located at the point of
      treatment or in  a  separate pretempering pumping  facility, or a combinatio
      of the two.  Figure 6-10 illustrates an ideal town  layout for this system.
      The pretempering/recirculating  and/or treatment  facility is preferably
      centrally located  and the community is divided into a number of single-
      looped sections.   By planning community growth in a dense circular pattern
      maximum efficiency can be made  of  this method of servicing.  The worst
      situation would  be a long strung-out community with the facility at one end.
      This usually ends  up increasing pumping requirements and duplication  of lines,
               As noted  in Figure 6-10,  back-of-lot mains are preferred if
      possible.  In arctic communities under 3000 in population there are very
      few, if any, paved roads.  Snow accumulation and drifting is often severe
    Loop links
1111^-7
From source
   t
ruini
          /
                Recirculating
                pumphouse
      Water mains
                        t
                                                            D D
                                                            D O
        FIGURE 6-10.   LAYOUT AND LOCATION OF MAINS FOR SINGLE-PIPE RECIRCULATION

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                                  6-21
and  roads  are  cleared  with a dozer.   If the mains are placed in the
street  (unpaved  gravel roads),  the manholes are subject to physical
damage.  If  the  lines  are shallow buried they are also subject to colder
ambient  temperatures because snow clearing reduces insulation.
         Placing the mains at the rear lot line not only avoids these
problems but reduces service line connections and permits service lines
of equal length  on  both sides of the  main.  With mains in the road
allowance, usually  to  one side,  plus  the normal 8 m requirement between
the  front  of the house and the  road  right-of-way, average service line
length would be  15  m on one side and  23 m on the other.  The cost per
hook-up would  be between $5000  to $7500 for the lot owner.  With the
mains at the rear lot  line, where houses can be placed as close as 3 m
from the lot line,  an  average service line length would be 6 m in either
direction  at a eost per hook-up  of approximately $2000.  There is a
significant  saving  to  the lot owner  in this method of servicing which
encourages development of piped  services.
         "Back yards"  are not used to a great extent in northern
communities.   If houses are placed in a planned fashion similar to
southern temperate  communities,  the  large area between the rear of the
houses could become wasted space. Depending on community attitudes,
this may be one  more reason for  placing mains at the rear lot line and
the houses as  close to it as possible according to fire regulations.
(For more  information  see Section 2.)
         A further  advantage of  mains located along the rear lot line is
that the manholes containing water line valves and hydrants, freeze
protection controls, etc.,  can be elevated in cylindrical shape
approximately  3  feet above grade. This results in easier access during
the winter as  the immediate area around the elevated manhole is blown
clear of snow  by local  winds.
6.5.2.2  Water wasting  -  conventional systems.   In this type of system
the water line network  is layed  out conventionally.  To ensure flow at
dead ends, loops, and  service lines water is bled off to  sewers at a
number of areas.

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                                 6-22
         Disadvantages of this system are the inevitably high water
consumption and possibly high energy input.  Consumption could go as high
as 4500 L/person/day (see Section 3).
         This system should not be used where there is a limited water
source, where water requires expensive treatment, or where  pretempering
of water is necessary as well as wasting.  Possible use would be where a
relatively warm inexhaustible water source exists, allowing  low initial
capital system cost through minimum pipe line lengths and pipe
insulation.
         A further drawback of the system is that sewage with highly
diluted characteristics and large volumes becomes expensive  to treat.
The City of Whitehorse, Yukon Territory, has such a water wasting system
with its incumbent sewage treatment problem.  Whitehorse has the
advantage of being able to  tap relatively warm  groundwater,  which reduces
operational costs.
6.5.2.3  Single pipe - no recirculation.  This  system  is employed to a
great extent in Greenland and requires for its  success complete coordina-
tion with town planning.  High volume users, such as large  apartment
blocks or fish processing plants are strategically located  at  the ends of
main lines to ensure a continual flow in the line without requiring  a
return loop (see  Figure 6-11).
        High density users
Low density users
1
1 ,1 r_
1 c
t lij
1 11 w 
L 	 LJ r"-
1 L_

mm


,1






1 1

P^IJ PI p FI


yl'W.'.'.1.'.'.*.1! f^v-j
l:-;-i!|:'::-l Oj

Mum- family
housinn
I
/ Watermair
/
jf

 . I***"!

r Ul I \\j\ lUUbt?

    Apartment blocks
          FIGURE 6-11.   SINGLE-PIPE  SYSTEM WITHOUT RECIRCULATION

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                                  6-23
         In Greenland, apartment  blocks  accommodating up to 1500 people
in one building are used  for  this purpose.   In  Canada, small community
sizes and the standard of housing make  it  impossible to implement this
type of system.
6.5.2.4  Dual pipe system.  In  this  type of  system a large supply line
and a small return line are placed side  by side either in a utilidor or
in a packaged preinsulated pipe  sysem  (see Figure 6-12).
                              Utilidor
                                     Foam insulation
                            Heat line supply
                               Heat line return
         Main water supply-
               Return water line-
                             Sewer-
Corrugated metal pipe
                            Packaged pre-insulated pipe
                Return line
      Main water supply line
          Foam insulation
           Outer covering
      FIGURE 6-12.  TYPICAL UTILIDOR AND  PACKAGED  PREINSULATED PIPE

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                                  6-24
          This system permits lines to be laid out in the normal manner.
 rhe  main  is  connected to the return line at the end of the line to ensure
 circulation.
          Service lines are taken off the main and return via the return
 line to ensure circulation through the service connection by the pressure
 differential  between the two mains.
          Heating of the mains can be provided either by pretempering the
 main supply  water or by utilizing separate heating lines.
          Control mechanisms for this type of system tend to be elaborate
 because varying consumption in different locations results in stationary
 water in  certain areas at certain times.  Thermostatically controlled
 solenoid  valves are required on "short circuit" branches between two
 lines at  regular intervals to overcome this problem (see Figure 6-13).
                        To building
                            1
Return line
Watermain
                                             Thermostatically operated valve opens
                                             on demand to add heat to return line
                      FIGURE 6-13.  DUAL PIPE SYSTEM
          Even with these or similar control devices it is difficult  to
 ensure 100% movement of water at all times.
          Other disadvantages of this system include:
          - The greater number of lines used increases initial  capital
            cost and energy consumption is high due to the greater  surface
            area.
          - The greater number of lines also increases the risk of  line
            breaks.  However, ultimate flexibility is allowed  in isolating
            line breaks and keeping everything serviced.

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                                 6-25
         While this system is not recommended as a main  system  it does
have application as a sub-system to the single-pipe recirculation system
or in long pipelines where there are no take off branches,  such as  supply
lines from source to community, etc.  The dual  pipe system  is often used
as a sub-system of a single-pipe recirculation  system  to  service existing
houses in small areas that are difficult to service from  the main loop  or
where it is impractical to extend the main loop (see Figure 6-14).

       From recirculating pumphouse
       Pumphouse
       Circulating  pump
         Electric heat  traced
       service line alternative
                                 CL
                                 O
                                 o
                                 c
                                 '03
                                 E
en
c
CO
                                        Circulating  pump
                                         v
  Dual main Sub-system
Small diameter
water pipe
        To recirculating pumphouse
                   FIGURE  6-14.   DUAL MAIN  SUB-SYSTEM
         The  sub system  in effect becomes an  elongated  service line
servicing a number of houses.   The unit at  the  end  of  the  line will have
a circulation  pump between the  two lines to ensure  that pretempering
water  from the main  loop is  circulated through  the  line.

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                                 6-26
6.5.3    Other methods
         Other methods either still in the development  stages  or  less
frequently used are as follows:
6.5.3.1  Small-diameter water distribution lines can be a  more cost-
effective method of delivery for both small and large communities.
         Small-diameter lines mean pipes of diameters from 50  mm  to  152  mm.
If full fire flow and hydrants were used the  lines  would range from  152  mm
to 305 mm in diameter.  The mode of circulation or  main freeze protection
mechanism would be any one of the types previously  described.
         Small-diameter mains require more emphasis to  be  placed  on  fire
protection through building structure, building materials, etc. and  the
use of sprinklers and hose cabinets in lieu of exterior hydrants.
         One advantage of such a system is in the net energy savings.
Less surface area means less heat loss.  There is also  greater movement
of water in the pipes, making the system more reliable. The pipes  can be
placed near or directly under houses due to lower capital  cost,
practically eliminating service line problems.
         Small-diameter piping systems are used extensively in Greenland
(see Figure 6-15), including the capital Godthab with a population  of
12 000, and in Alaska, where 50 mm to 102 mm  have been  used by the  U.S.
Public Health Service.  In Greenland, in lieu of  factory insulated  pipe,
small diameter water mains and sewer lines are insulated and wrapped
on-site.
6.5.3.2  Intermittent or batch water supply has been proposed for small
communities as the most cost-effective method of  distributing water
[2,3],  Under this system, small diameter lines would go into and out  of
each house in a series of continuous loops.   Water  would be distributed
at only certain times or on certain  specified days.  The lines would be
preheated, water distributed say for eight hours  every  Monday, Wednesday
and Friday, and then  the lines would be blown out  with  air.  The  latter,
however, is not a very reliable method  of dewatering lines.
         In houses with existing 1136-L holding  tanks,  it  would be  the
homeowner's responsibility to open and  close  a valve on the water line to
fill his holding tank.  Utilizing  the existing storage  capability in the
house in this manner  is very attractive, especially for those communities

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                                  6-27
                FIGURE  6-15.   SMALL-DIAMETER  WATER MAINS
where water use is restricted  by  the  lack of  a  continuous  source,  where
expensive storage reservoirs had  to be built.   In  such  communities it is
expensive to  truck water; yet  if  fully-piped  systems  were  used,  increased
water consumption would  either deplete the community's  water  source or
very large reservoirs would have  to be constructed.
6.5.3.3  Summer line systems are  useful  in many communities where
permanent lines are not  economically  feasible.   Local  topography and
conditions, plus economics and convenience, may make  uninsulated summer
lines desireable.
         Such lines often take advantage of sources of  water  that  allow
flow by gravity to the  community.  In other oases  they  are used  in
conjunction with pumping systems.  Eliminating  the need for trucked water
for up to four months and using inexpensive above-ground  lines reduces
overall costs.  The summer lines  can  also be  used  to  fill  reservoirs for
winter use.
         There are many  different  forms  of summer  lines but since  they
are not unique to cold  regions no  further detail on this  topic will be
given in this manual.
6.5.3.4  Lines with "flushing hydrants" are used to prevent sewer  lines
from freezing up where  relatively  few hook-ups  are on  the  end of a long

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                                 6-28
line.  A small amount of water (5 to 10 L/min) is bled  into  an  end-of-
line sewer manhole.  The bled water is syphoned  into  the  sewer  line  in
predetermined batches, as shown in Figure 6-16,  at regular intervals
determined by the flow of water and volume held  in the  manhole  before  the
syphon action takes place.
6.6      Service Lines
         Service lines are usually incorporated  as part of a service
bundle or utilidette.  The common service bundle package  used in  arctic
Canada is as shown in Figure 6-12.
         Double recirculation lines are recommended in  all cases.
However, single-line systems with electric heat  trace to  prevent  freezing
have been and are still being used by lot owners.  The  single-line  system
uses a great deal of electric energy which, in isolated communities,
costs as much as $0.25/kWh.  For this reason  its use  should  be  carefully
evaluated.  Service lines entering the house  must be  isolated and/or
protected against movement.
         Main elements of the service line are described  below.
6.6.1    Method of circulation
         The two most common methods are a pump  inside  the housing  unit
and pitorifice circulation.  Pitorifices must have a  0.61 m/s velocity in
the mains to operate properly.  However, they cannot  be used for  service
line circulation if the lines are longer than 25 metres.  Beyond  this
length, a small circulation pump must be added in the house. Observed
head losses across pitorifices are given below.  These  measurements were
made in 1975 in the Kotzebue system to determine the  head loss  in the
main line loops due to the presence of the pitorifice fittings.
Loop
KEA
loop
uptown
loop
centre
loop
Length
(m)
12 300
11 055
8 250
Number of
Services
110
80
93
Head Loss/ Service
(pair of pitorifices)
0.31 kPa/pair (3.3 cm/pair)
0.32 kPa/pair (3.3 cm/pair)
0.34 kPa/pair (3.6 cm/pair)

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                                                       11000 Manhole
From water main
 Valve and vacuum breaker
 End of sewer manhole
(see detail)
                                                                       Overflow and flush well




                                                                       150 x 200 Tee  wye



                                                                          To sewer
                                                        200 to 150  Reducer

                                                        125 Siphon
                                       I
                                      NJ
                                      VO
                                         FIGURE  6-16.  FLUSHING MANHOLE SYSTEM

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                                     6-30
         The measurement of head loss is valid  for  a  101.6  mm main line
flow of 6.75-7.5 L/s and 5 cm-1.9 cm pitorifices.   A  conservative design
loss of 6 cm per pair could be used.
         The head losses in the pumphouse  plumbing  on each  system must
also be calculated.  These losses are substantial on  most systems.
        The main back-up freeze protection  is an electric heat trace ther-
mostatically controlled from  the housing unit,  with high and  low temperature
limits.  If copper  pipe is used as a carrier a  metal  band across the two
pipes at the mains  can provide electric resistance  thawing  from within
the house as a second back-up system (see  Figure 6-17 for details).
         Another method is to insert a small-diameter probe into the
frozen pipe from the house and force hot water  through it.   (See Appendix F).
6.6.2    Materials
         The standard service bundle includes a preinsulated  101.6 mm
diameter sewer line (65 mm water lines and  a 18 mm  conduit  for pulling
in heat trace cable).  The overall diameter is  approximately  300 mm with
a 41 mil yellow jacket placed on the outside.   If the service bundle is
exposed or used as  an above-ground service, a metal outer  jacket is also
recommended.
         Details of above and below-ground service  box take-offs are
shown in Figures 6-18, 6-19 and 6-20.  Note details concerning service
valves and operating stems.   These are a must in order to  isolate a
service without digging it up and damaging the  insulated hook-up box.
Other special precautions are taken, such  as packing  the valve box
assembly with low-temperature nonhardening grease  to  prevent  water from
freezing around the mechanism and making  it inoperable in  winter.  The
top of the valve box assembly is terminated about 10  cm below grade to
prevent damage by playing children,  snowmobiles, etc.
6.6.3    Dual servicing
         When adjacent housing units have  a common  owner,  suoh as in
public housing, common services are  often  used  as  shown in  Figure 6-21.
The water lines are so arranged that the  supply goes  into  one house
through the circulating pump, out  the  return line  to  the main.  In other
words, a small water loop connects two houses using the same service bundle.

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                                                         6-31
                                              li
               Dielectric couphngs-

                    Flortrir, heal tape
                                                         Service line from mam to building-
4/o Copper wire connected  to both
18 0 copper service pipes to form
an electrical connection


                      A*l
                         i    ~~
        f~-	.			^-^~^S-.

        \                    I
                                                                 Foamed in place
                                                                 polyurethane
                                                                 insulation
                          Pitonfice
                                                                                Section A-A
                                     FIGURE  6-17.    WATER  SERVICE  LINE
300
                                                  Polvurethane insulation


                                                  Mam stop and access sleeve


                                                  Insulation cut and filled
                                                  with polyurethane foam

                                                  Metal jacket
                                                 180  Polyethylene supply
                                                 and return lines with
                                                 coupling and removable plug
                             100 0 Sewer service
                             and pipe
                             with grooved end
Polyethylene
nsulation wrap
             150 0 Steel sewer        150 0 Steel watermam


                               FIGURE 6-18.   ABOVE-GROUND SERVICE  LINE
                                                                                                  Filled with polyurethane
                                                                                              Section I

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                            6-32
                                               Pipehanger
                                                              150 0 Sewer line with
                                                              75 mm insulation
                                                              and metal outer  jacket
    Service box
    right access
                                          150 or 200 0 Watermain
FIGURE  6-19.   ABOVE-GROUND SERVICE  LINE  TAKE  OFFS
                                     100 x 101) mm Gt.fi,ir pOSt

                                     Thaw cable
                                     1500 Onto valve

                                     Grade
                                     Granular fill all around

                                   ^_ Cast iron extension bo* with
                                     cover and foamed in place polyurelhane
                                     50 mm Polystyrene plug


                                     100If Polyethylene sleeve

                                     Extension stem to underside of cover


                                     Preformed or foamed in place
                                     polyurethane insulation


                                     Permagum seal between all joints
       FIGURE 6-20.    UNDERGROUND VALVE AND BOX

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                                 6-33
                 To building
          Circulating pump
              SEE DETAIL
              Common service bundle
                  Sewer line
                  Watermain
                               Foam insulated service bundle
                                                            Sewer cleanout
                             Water supply from mam
                                              Return line to mam
                       FIGURE 6-21.  DUAL SERVICING
         This  cuts the capital installation  cost of the service line  to
each house by  approximately 1/3, and  increases the reliability due  to
greater consumption and dual circulation  pumps on the one loop.
6.7
Materials  of  Construction
         Described below are the most common  materials used for  piped
water distribution in northern regions.   The  materials are broken  into
two categories.   Category 1 materials are considered the best materials
for northern  use.   Category 2 materials  should be used only if design
conditions  allow their use in a safe dependable manner.

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                                 6-34
6.7.1    Category 1 materials
6.7.1.1  Copper is mainly used in  service  lines because  it  can  be
thawed using electric resistance.  Type K  only is  recommended.
6.7.1.2  Ductile iron pipe can take  shock  loadings and has  some
flexibility.  Corrosion resistance is low  and lining  should be  used  as
with cast iron.  It is very durable  and fairly heavy.  Its  use  is
recommended through rocky areas and/or where sand  or  gravel bedding
materials are not available.  It is  the best of the steel or east  iron
pipes but relatively expensive (about $11.50/m for 10 cm).   (C  = 125).
         Ductile iron with tyton or  victaulic joints  is  also used  where
bridge strength is required.  This occurs  when spanning  piles above-
ground or where there is a possibility of  isolated settlement below-
ground.  Ductile iron also can be  thawed using electrical resistance.
6.7.1.3  Steel pipe.  The description for  ductile  iron also applies  to
steel, except it is less corrosion resistant, somewhat lighter  and more
flexible.  The flexibility is hard on linings.  Flexible epoxy  linings
are being developed which should be  more durable.   Continuously welded
steel pipe is also used (especially  in above-ground systems) to obtain
maximum spans between piles.  It can be thawed using  electrical
resistance.  Expansion and contraction, including  necessary thrust anchors,
must be taken into consideration.
         Steel pipe can be connected using a method called  "zap lock".
In this method two pipes of the same size  with the ends  bevelled to  fit
into one another are hydraulically rammed  one inside  the other  in  the
field.  A layer of epoxy cement is applied prior to the  ramming process.
The resulting overlap of approximately 35  cm gives a  joint  that is stronger
than the pipe.  This method is a good alternative  to  continuously-welded
steel pipe and can be carried out  quickly  in the field at cold  temperatures.
6.7.1.4  Plastic pipe is just coming into  its own. It is light (5.0 m
section of 10 cm diameter weighs about 12.8 kg), flexible,  and  has a
smooth interior (C = 150).  Bedding  is not as critical but  still must be
done properly.  It is easy to install but  a little more  expensive  than
metal pipes.  It has a higher coefficient  of contraction and expansion

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                                 6-35
than the other materials and this must be taken  into account  at  joints.
The recommended type for northern regions is high molecular weight
polyethelene.
         High density polyethelene (PE) is very  flexible  and  impact
resistant.  It cannot be threaded.  PE is used widely  for service lines
and main lines.  Butt-fused PE pipe is used extensively in Canada for
water distribution and sewage collection lines.  The pipe is  insulated
with urethane and the outer pipe is also PE (the outer pipe joints are
heat shrink couplings).  It is claimed that it can  freeze solid  and  be
thawed using a heat trace line without rupturing or breaking  [4].
         Other materials are used where bridge strength is required.
Precautions must be taken if laid above-ground to account for large
expansion and contraction.
         Pipe take-offs from fixed joints such as pumping stations must
be supported in case of ground settlement, which would cause  unacceptable
stress on the pipe joint (see Figure 6-22).
                                         density polyethylene pipe
                          Pipe support
                  FIGURE 6-22.   SUPPORTED  PIPE  TAKE-OFF
6.7.2    Category 2 materials
6.7.2.1  Cast iron is probably the oldest  (in use  in  Germany since  1455
It is relatively corrosion resistant if cement-lined  and  tar-coated,  and  )
providing the lining is not damaged before or during  installation (damage
occurs easily).  Unlined pipe should not be used.   It  is  heavy and  hard
to handle, but durable (6.1 m section of 10 cm  diameter weighs 225  kg).

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                                 6-36
6.7.2.2  Asbestos-cement pipe is being used extensively in  temperate
climates.  It must be carefully bedded or uneven loading will  break it.
It is extremely corrosion resistant.  It is relatively light (a 4 m
section of 10 cm diameter weighs about 30 kg), easy to install and is
nonmetallic.  It is not costly (about $6.00/m for 10 cm diameter).  It
has a smooth interior (C = 140) and retains it longer than  the metal
pipes.
         Asbestos-cement pipe should never be used for northern work  in
buried conditions in soil subject to settlement or frost heave.
6.7.2.3  Plastic pipe.  Polyvinyl chloride (PVC) pipe is the most
common type used in water mains.  Type I is stronger; Type  II  is more
impact resistant but not rated for as high pressures.  In cold climates  a
Type I/Type II is used to gain part of the benefits of both.   It can  be
threaded and has the same cross-section dimensions as steel.
         PVC pipe is manufactured in two basic types.  First are the  SDR
classes which have constant  pressure ratings for all sizes  throughout
each class.  SDR is an abbreviation for sidewall diameter ratio.   SDR 26
pipe, which is rated for 1103 kPa, is widely used for water mains.
Second are Schedules 40, 80  and 120, which roughly correspond  to iron
pipe sizes and have more uniform wall thicknesses for different  sizes
within each schedule.  This  sizing procedure results in  small-diameter
pipes having much higher pressure ratings than larger pipes in the  same
class.
         Both of these general types are designed for pressure applications
and are used mainly for water systems.  PVC pipe, designed  specifically
for sewer use, has, in the  past, been thin-walled and breakable.   For
this reason, considerable quantities of the SDR 26 pressure-rated  pipe
have been used for sewer lines in recent years.  Non-pressure  rated  pipe
with thicker walls is now being manufactured under the ASTM designation
shown below for PVC sewer pipe and has proven very satisfactory.   PVC
pipe is covered by the latest revisions of  the  following  ASTM  standard
specifications:
         PVC pipe and fittings (SDR classes) - D-2241
         PVC pipe and fittings (Schedules  40,  80 and  120)  - D-1785
         PVC sewer pipe and  fittings - D-3034

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                                 6-37
         The design and installation practices recommended  by  the  PVC
pipe manufacturer should be complied with.  Many manufacturers have
compiled very good booklets covering PVC pipe and are quite willing  to
provide these to actual or potential customers.
         PVC pipe is not recommended for single-pipe buried installations
in permafrost.
         Acrylonite-butadiene-stryrene (ABS) has high impact strength and
flexibility but has low mechanical  strength (half that  of PVC).  It  does
not become brittle at cold temperatures.  ABS is being  used primarily for
non-pressure drainage, waste and vent (DWV) work.
         ABS has also been used by  the U.S. Indian Health Service  for
sewer mains, service lines and drain field installations.   This  pipe is
not as readily available as PVC in  some sizes.  In general, ABS  pipe has
a higher impact strength than PVC in the more common types  but it
requires a thicker wall to be equivalent to PVC in pressure rating.
Ratings and nomenclature for different types of ABS pipe are basically
the same as those for PVC.  ASTM standard specifications covering  ABS
pipe are as follows:
         ABS pipe and fittings (SDR classes) - D-2282
         ABS pipe and fittings (Schedules 40, 80 and 120) - D-1527
         ABS sewer pipe and fittings - D - 2751
         Design information is available from manufacturers and  should
be followed closely.  Again, ABS is not recommended for single-pipe
buried installations in permafrost.
6.7.3    Other types of pipe used
         Regular or prestressed, reinforced concrete pipe is used,
usually for larger transmission lines.
         Wood stave piping is good  in cold regions because  of  its
insulation value.  It is expensive  and corrosion-free (except  for  the
wire).  C = 140 and does not change with age.  It is also able to
withstand freeze-thaw cycles without breaking.
6.7.4    Miscellaneous fittings
         Joints - bell and spigot (rubber o-ring), mechanical  joint,
dresser couplings, solvent welding, threaded, etc.

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                                  6-38
         Service lines are nearly all copper now but polyethelene  is
being used more and more.  The copper has the advantage of  being
electrically thawable, but PE is considerably cheaper, easier  to  install,
and can withstand freeze-thaw.
         Dresser or other type repair clamps should always  be  kept  on
hand for all pipe sizes in the distribution system to  repair leaks.
         Valves should be AWWA approved types, rated for  the pressure
under which they will have to work [5],
         There are four basic groups of valves:  globe, rotary (butterfly,
plug, etc.), slide (gate) and swing (check valves).  Plug and   ball  type
valves are older; gate valves are most widely used now.   All valves  that
need frequent adjustment or operation should be furnished with a  valve
box to the surface.
6.7.5    Insulation
         Pipes of the materials noted above, when used  in individual
piping systems, are normally insulated with high-density  urethane foam
under factory conditions and covered with a 40-mil high-density polyethe-
lene jacket or steel, depending on the exposure of the material when
used.  The factory-insulated pipes are shipped to the  job site complete
with preformed half shells of urethane for the joints.  Heat  shrink
sleeves, or polyken tape is used to complete the  joint  in the  field where
high-density polyethelene is used as an outer jacket.   For  pipes
insulated and covered with a steel jacket, a special metal  jointing
section is used.
         Except  for appurtenances using urethane, insulation  is not
normally done in  situ because of the high cost and high labour
requirement.  There is also a lack of end-product quality.
6.8      Appurtenances
6.8.1    Hydrants
6.8.1.1  Above-ground.  Above-ground hydrant housings  must  be  tailor
made to fit the  particular design.  They are generally of the  Siamese
building wall hydrant type.
         Figure  6-23 shows a  typical above-ground  hydrant with its
individually-designed insulated housing.  The distance from the main is

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       Removable preformed
       polyurethane sections

Foamed in place polyurethane

                Angle valve
                                                     Handwheel
                                                     Metal cap

                                                            Drip lip
C  Siamese
   hydrant
                                                                      Galvanized pin
                                                                      and chain
                                                                       Insulation
                                                                          Watermain
                                                                                      OJ
             FIGURE 6-23.  ABOVE-GROUND HYDRANT

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                                  6-40
kept as short as possible  so  that heat conduction  from the  water flowing
through the main keeps the water in  the  hydrant  from  freezing.   The
hydrant housing is painted fluorescent yellow.
6.8.1.2  Below-ground.  A  typical below-ground hydrant installation is
shown in Figure 6-24.  The hydrant is normally on-line to minimize
possibility of freezing, with a frost-isolating  gasket between  the bottom
of the hydrant barrel and  the tee into the main.   The hydrant barrel is
insulated with 7.62 cm preformed polyurethane and  placed  inside a 50 can
diameter polyethelene series  45 pipe sleeve.  The  cavity  between the
sleeve and the insulated barrel is filled with an  oil and wax mixture to
prevent damage to the hydrant due to frost heave.
         Isolating valves  are normally put on either  side of tee into the
main to allow for hydrant  replacement or repair.
         An appropriate mixture of propylene glycol and water of a grade
acceptable for potable water  systems is  pumped into the empty hydrant to
prevent the hydrant from freezing.   After use, the hydrant  must be pumped
out and recharged, since permafrost  conditions may prevent  self-draining.
6.8.2    Valves
         Above and below-ground valves are basically  the  same,  with the
exception of the valve box and operating stem details. Typical details
for such installations are shown in  Figures 6-19 and  6-20.
         Again, foamed-in-place polyurethane insulation is  used with a
series 45 polyethelene sleeve over the operating stem filler, similar to
hydrants.  Valves generally used for buried installations or where the
valve is completely insulated are nonrising stem-gate valves.  In other
situations, sueh as in manholes, any appropriate valve can  be used.
6.8.3    Metering
         Standard meters are  used to monitor flow  in  the  distribution
system, including magnetic flow meters,  in-line  gear  meters, and orifice
pressure differential recording graph meters.
         Both the supply and  return  lines must be  metered  in circulating
systems with one or more loops.  The difference  gives the daily consump-
tion.  Under fire conditions, a reverse  flow meter or bypass is required
on the return line.

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              6-41
                    Fire hydrant

                     Permagum seal
                     Isolating gasket

                     Metal cap

                     Grade
                     500 0 Polyethylene series 45 pipe sleeve
                     Oil and wax mixture filled to metal cap

                     75mm Preformed polyurethane
                     Shrink sleeve

                     50 mm Polystyrene bottom  plug
                                   Insulation
                                      Watermain
                    Field applied polyken tape
        Field applied sealant on insulation surfaces
FIGURE 6-24.  BELOW-GROUND HYDRANT

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                                6-42
         Most northern communities are relatively small.  This means  the
fire flows are as much as 10 to 15 times greater than the average  flow.
In this case an orifice plate meter which is satisfactory for fire  flows
will give unsatisfactory results under normal conditions.   If it gives a
satisfactory graph under normal conditions then the orifice  plate  is  such
that it restricts flows during a fire situation.  Both magnetic  flow
meters and gear-driven meters are very expensive for large  diameter pipes.
In most instances, the large diameter supply pipe flow is diverted
through a small pipe through one of the latter two meters,  and  then back
to the larger supply size pipe.  During fires the meters are completely
bypassed and flow is directed through the large supply lines.
6.8.4    Manholes
         Manholes for both water and sewer requirements have been
constructed of a number of materials.  Common types are:
         - concrete,
         - corrugated metal, and
         - welded steel.
All of these have varying means of insulation.
         The main problems in the past with manholes were that  they were
too small, leaked excessively, or were subject to damage.   One
alternative which evolved in the Northwest Territories is the manhole
shown in Figure 6-25, known as the "mini service-centre manhole".
         The manhole shown in Figure 6-25 is a comprehensive one  showing
both water and sewer lines as well as a hydrant, but the  same basic
design is used for any situation.  The interior layout and  size  are
designed to fit the requirements.
         The basic concept is that all necessary day-to-day maintenance
of the distribution mains can be carried out in a climate controlled
environment.  This includes maintenance of water line valves, hydrants,
heat trace power point, and sewer cleanouts.
         Some of the features of such a manhole for northern work are:
         Hydrants    - Standard hydrants can be used and  operated  in
                       the normal manner.

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                 6-43
                                                  Concrete
                                                  manhole
                                                 Foam insulatior
FIGURE 6-25.  MINI SERVICE-CENTRE MANHOLE

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                       6-44
            - One isolating valve plus valve boxes and  operating
              stem extension are eliminated, reducing
              installation cost.
            - Replacement is easier; no digging is required.
            - Relatively fool proof compared to glycol  filled
              hydrants.
Main valves - These are placed in manholes giving easy  access
              for operation or replacement and eliminating
              valve boxes.
Manhole
Structure   - The manholes are well insulated for energy
              conservation
            - They are large:  minimum size 1.2 ttr depending
              on interior fittings.
            - All exposed surfaces are metal or concrete:
              relatively vandal-proof and maintenance-free.
Power Point/
heat trace  - Heat trace lines and control points are terminated
              in the manholes.  Replacement heat trace  lines can
              be pulled in from one manhole to the next.
            - A thermostatically controlled electric heater
              keeps the temperature above freezing.
            - There is an electric plug for lights and  small
              power tools.
Sump pump   - The sump pump is located in a prefabricated  steel
              sump pit set in the concrete base.  The pump comes
              on automatically if water from a used hydrant or
              groundwater enters the hydrant and pumps  through
              a back flow preventer into  the closed sewer  line.
Sewer
cleanout    - Closed sewer cleanouts are  provided in the manhole;
              covers have rubber gaskets  so excess pressure can
              be detected.

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                                6-45
6.8.5    Alarms and safeguards
         Alarms and safeguards are a very important  part  of  any system.
Flow alarms are a necessity in any circulation  line  to  warn  of  stopped
circulation.
         Low heat alarms are needed to warn of  impending  freeze-ups.
Flow meters are especially important to adjust  flow  in  the return
circulation loop.
         The alarms should be wired to the operator's house  and be  loud
enough at the pumphouse to wake  someone and get them there to check out
the trouble.  Alarms must be tested at least weekly  to  be sure  they are
operational.  A central control  panel should be provided  either in  the
operator's house or the pumphouse.
6.9      Backup Freeze Protection Mechanisms
         The main backup freeze  protection mechanisms are:
         - heat trace systems,
         - thaw wire electrical  resistance systems,
         - steam or hot water thawing.
6.9.1    Heat trace systems
         This is the standard back-up system used  in most piped water
distribution systems.  While it  is effective, both the  initial  capital
cost and operating cost for this type of insurance are  substantial. The
cost of installing heat trace systems is approximately  $30/m of line,
including material and labour for the overall system.
         Constant monitoring must be carried out on  such  electrical
systems if they are to perform as intended.  If the  controlling thermo-
stats are not working properly or the sensing bulbs  are in the  wrong
location, either too much electric energy will  be  expended at great cost
or it will fail to do the job when required.
         Easy replacement of heat trace lines should be a standard
feature of any system.  The heat trace normally used is the  constant watt
per foot type placed in a conduit or channel next  to the  pipe with  or
without heat contact cement.  Common wattages used are  2.5 watts per foot
for service lines and 4 watts per foot for main lines.  This method of

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                                  6-46
placement of heat trace lines is relatively less  efficient  on plastic
pipes.  In Greenland and Northern Scandanavia  the  heat  trace  is  placed
inside plastic pipes.
         Care must be taken to ensure  the conduits are  sealed.   Otherwise
they will allow groundwater to enter the electrical system  and manholes.
6.9.2    Thaw wire electric resistance systems
         This system can only be incorporated  on  piping  materials  that
will pass an electric current, such as copper  and  steel.  A current is
induced into sections of the pipe through strategically-placed  thaw wires
by a portable electric generating unit.  The resistance  and resulting
heat thaws out the pipe.
         The initial capital cost for  this backup  thaw  system is low.   It
is only used if the pipe is already frozen, as  opposed  to heat  trace
systems which add heat before freezing takes place.
6.9.3    Steam or hot water thawing
         This system uses a source of  steam, such as a  portable  steam
jenny, or hot water introduced under pressure  into the  frozen pipe via a
suitable hose or tube to thaw out the  pipe.  This  system can  be  used on
many types of materials.  It is not recommended for use  on  plastic pipes
which could melt or be damaged if the  procedure used is  improper.
         An example of the difference  in the cost  of heat  tracing  systems
versus steam thawing was noted in Norman Wells, N.W.T.,  where a  portable
steam jenny was purchased in lieu of an electric  heat trace system for
the welded steel pipe system.  The difference  in  initial capital cost  for
approximately 1800 m of mains was $95  000.  This  difference will increase
as more mains are installed because the steam  jenney can be used for
other purposes.
         The great difference in cost  encourages  careful consideration of
the alternatives to a heat trace system.
         While heat trace systems appear to be  the trend in back-up
thawing for single-loop reoirculation  systems,  better prefabricated
insulated pipe packages, and simple control and alarm systems warrant
re-evaluation of the justifications for a heat  trace system.

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                                     6-47
          For thawing small service lines a power pump, a hot water
reservoir and small probe tube as described in Appendix F has proved most
successful and superior to other methods.  Helpful tips, tables and

guidelines for thawing frozen water lines are also given in Appendix F.
6.9.4     Freeze damage prevention

          The reduction of damage to water distribution pipes when
freezing occurs has been discussed by McFadden [6].   The use of a

diaphram at the last point to freeze in each section of pipe was

recommended as a good technique to reduce damage.  The location of the

proper point can be selected and somewhat controlled by careful analysis
of the system and careful placement of additional insulation.
6.10      References
1.   Government of the Northwest Territories, Department of Local
       Government, "General Terms of References for an Engineering
       Pre-design Report on Community Water and Sanitation Systems",
       Yellowknife, August 1977.

2.   James, William and Ralph Suk, "Least Cost Design for Water
       Distribution for Arctic Communities", McMaster University
       Hamilton, Ontario, May 1977.

3.   James, William and Ralph Suk, "Design Examples:   Least Cost Water
       Distribution Systems for Pangnirtung and Broughton Island, N.W.T.",
       McMaster University, Hamilton, Otario, May 1977.

4.   O'Brien, E. and A. Whyman, "Insulated and Heat Traced Polyethylene
       Piping Systems - A Unique Approach for Remote  Cold Regions",  In:
       Utilities Delivery in Arctic  Regions, Environmental Protection
       Service, Environment Canada,  Report No.  EPS 3-WP-77-1,  Ottawa,
       1977.

5.   Edwards, J.  "Valves, Pipes and Fittings", Pollution  November  1971.

6.   McFadden, T.,  "Freeze Damage Prevention in Utility Distribution Lines
       In:   Utilities Delivery in Arctic Regions, Environmental Protection",
       Service, Environment Canada,  Report No.  EPS 3-WP-77-1,  Ottawa 1977.

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                                 6-48
6.11     Bibliography

    Alter, A.J.,  "Water Supply in Cold Regions", Cold Regions Research and
    Engineering Laboratory, Monograph III-C5a, Hanover, New Hampshire, 1969.

    Bohlander, T.W., "Electrical Method for Thawing Frozen Pipes", AWWA
    Journal, May 1963.

    Buck, C., "Variable Speed Pumping has Many Advantages", Johnson
    Drillers Journal, May-June 1976.

    Canada Department of Indian Affairs, "Handbook of Water Utilities,
    Sewers and Heating Networks Designed for Settlements in Permafrost
    Regions", Translated from Russian by V. Poppe, 1970.

    Carlson R. and J. Butler, "Alaska Water Resources Research Needs for
    the 70fs", Institute of Water Resources, Univ. of Alaska, Report
    #IWR-39, Fairbanks, 1973.

    Cheremisinoff, N. and R. Niles, "A Survey of Fluid Flow Measurement
    Techniques and Fundamentals", Water and Sewage Works, December 1975.

    Crum, J.A., "Environmental Aspects of Native Village Habitat Improve-
    ment in Alaska", Standford Eng. Econ. Planning Report, EEP-46, 1971.

    Dawson, R.N.  and J.W. Slupsky, "Pipeline Research - Water and Sewer
    Lines in Permafrost Regions", Canadian Division of Public Health
    Engr., Manuscript Report No. NR-68-8, 1968.

    Easton, E.R., "Reservoir Liners for Use in Arctic Water Supplies",
    Arctic Health Research Centre, Fairbanks, Alaska, 1961.

    Gamble, D. and C. Janssen, "Evaluating Alternative Levels of Water
    and Sanitation Service for Communities in the N.W. Territories",
    Canadian Journal of Civil Engineering. Vol. 1, No. 1, 1974.

    Gardeen, J.,  "How to Fathom Liquid Level Sensing", Water and Wastes,
    May 1976.

    Gaymon, G.L., "Regional Sediment Yield Analysis of Alaska Streams",
    Journal of the Hydraulics Div., ASCE, January, 1974.

    Gordon,  R., "Batch Disinfection of Treated Wastewater With Chlorine
    at Less  than 1C", U.S. Environmental Protection Agency, Report
    # 660/2-73-0, Fairbanks, Alaska, September, 1973.

    Government of the Northwest Territories, Department of Public Works,
    Equipment Specification No. 601, Municipal Water Delivery Truck
    Hydraulic Drive, Yellowknife, NWT.

    Grainge, J.W., "Arctic Heated Pipe Water and Waste Water Systems",
    Water Research, Vol. 3, Pergamon Press, 1969.

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                              6-49
James, William, and A.R. Vieirn-Ribeiro, "Arotie  Hydrology  Project,
Baffin Island Field Program  1971 and 1972", McMaster  University,
May  1977.

James, F., "Buried Pipe  Systems in  Canada's Arctic",  The Northern
Engineer. Fall, 197.

Kill, D., "Cost Comparisons  and Practical Applications  of Air  Lift
Pumping", Johnson Drillers Journal, September-October,  1974.

Page, W.B., "Report on Tests Conducted  to Design  Pitorifiees and to
Measure Heat Losses from House Service  Pipes at Washington  State
College", Pullman, Washington, April, 1953.

Poss, R. J., "Distribution System Problems", AWWA  Journal, Vol.  52,
No.  2, February, 1960.

Reiff, F., "Hydropneumatic Pressure Systems", U.S.  Indian Health
Service,  Anchorage, Alaska,  1967.

Ryan, W.L., "Design and Construction of Practical Sanitation
Facilities for Small Alaskan Communities", Paper  included in 2nd
International Permafrost Conference Proceedings,  National Academy
of Science, Washington, D.C., 1973.

Ryan, W.L., "Methods of Pipeline Construction in  Arctic Areas",
U.S. Indian Health Service,  Anchorage,  Alaska, September 30, 1971.

Ryan, W.  and J. Grainge, "Sanitary Engineering in Russia",  AWWA
Journal,  June, 1975.

Sanger, F.J., "Water Supply, Sewage Disposal and  Drainage in Cold
Regions", U.S.  Army Cold Regions Engineering and Research
Laboratory, Hanover, New Hampshire, 1964.

Simonen,  E., "An Evaluation  of Municipal Services in  the Mackenzie
River Delta Communities", Univ. of Toronto, Masters Thesis  with G.
Heinke, Toronto, Ontario, October,  1970.

Smith, D.W., ed., Proceedings Symposium on Utilities  Delivery  in
Arctic Regions, March 1976,  Environmental Protection  Service,
Environment Canada, Report No. EPS 3-WP-771, January 1977.

U.S. Department of Health, Education and Welfare, Division  of  Indian
Health, "Design Criteria for Indian Health Sanitation Facilities",
Anchorage, Alaska, 1972.

U.S. Environmental Protection Agency, "Manual of  Individual Water
Supply Systems", Publication #24, Washington, D.C., 1962.

Watson, et al., "Performance of a Warm-oil Pipeline Buried  in
Permafrost", Proceedings of  2nd Int. Permafrost Conference, Yakutsk,
USSR, 1973.

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                                SECTION 7
                          WASTEWATER COLLECTION
                                  Index
                                                                    Page
7.       WASTEWATER COLLECTION                                      7-1
7.1      Sources of Wastewater                                      7-1
7.1.1    Domestic waste                                             7-1
7.1.2    Industrial waste                                           7-3
7.1.3    Public uses                                                7-3
7.1.4    Water treatment plant wastes                               7-3
7.2      Individual Bucket Systems                                  7-4
7.2.1    Hauling containers                                         7-4
7.2.2    Disposal point                                             7-5
7.3      Vehicle-Haul with House Storage Tanks                      7-7
7.3.1    Facilities at pick-up point                                7-7
7.3.2    Hauling vehicles                                           7-9
7.3.3    Disposal site                                              7-12
7.4      Piped Collection Systems                                   7-13
7.4.1    Design considerations                                      7-13
7.4.2    Conventional gravity collection lines                      7-15
7.4.3    Pressure sewage collection systems                         7-21
7.4.4    Vaouum sewage collection systems                           7-26
7.4.5    Other collection systems                                   7-30
7.4.6    Piped collection system materials                          7-30
7.4.7    Pressure and alignment testing of sewer lines              7-30
7.5      Lift Stations                                              7-31
7.5.1    Types                                                      7-31
7.5.2    Cold regions adaptations                                   7-31
7.5.3    Foree mains            -                                    7-33
7.6      Building plumbing                                          7-33
7.7      Typical oonstruetion costs                                 7-34
7.8      References                                                 7-34
7.9      Bibliography                                               7-37

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                             List of Figures
Figure                                                              Page
 7-1     Waste Disposal Pit                                         7-6
 7-2     Truck for Collecting Honeybucket Wastes - Barrow, Alaska   7-8
 7-3     Tracked Sewage Pick-up Vehicle - Arctic Village,
         Alaska                                                     7-8
 7-4     Individual House Holding Tank                              7-10
 7-5     Low Water Use, Foot Pedal Operated Toilet                  7-10
 7-6     Filling and Emptying Procedure for Holding Tank Pumpout
         Trucks                                                     7-12
 7-7     Sewage Collection Lines on Piling - Bethel, Alaska         7-14
 7-8     Small Utilidor Laid Directly on the Tundra Surface
         Carrying Water, Sewer and Glyeol Lines - Noorvik, Alaska   7-14
 7-9     Typical Sewer and Water Bedding Details                    7-17
 7-10    Sewer System Manhole                                       7-17
 7-11    Sewer Cleanout Detail                                      7-19
 7-12    Single Line Siphon                                         7-19
 7-13    House Sewer Wall Connection                                7-20
 7-14    House Sewer Floor Connection                               7-21
 7-15    Typical Pressure Sewer Installation                        7-22
 7-16    Typical Pump-grinder Installation                          7-22
 7-17    Pump-grinder Characteristics                               7-24
 7-18    One-pipe Vacuum System Schematic                           7-27
 7-19    Vacuum Toilet                                              7-27
 7-20    Grey Water Valve                                           7-29
                              List  of  Tables
Table                                                                Page
 7-1      Characteristics  of  Wastewater Collection Systems           7-2
 7-2      Types  of  Lift  Stations                                      7-32
 7-3      Unit Construction Costs  (1977)                              7-35

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                                   7-1
 7.        WASTEWATER COLLECTION
          Wastewater collection systems collect wastewater from users
 and transport it to the sewage treatment facility or disposal point.  The
 sources of wastewater and types of collection systems and design para-
 meters are presented in this section.  As presented in Section 2, the
 main types of collection systems are individual bucket haul, vehicle-haul
 with house storage, and piped.  Table 7-1 summarizes the characteristics
 of  wastewater collection systems.
 7.1      Sources of Wastewater
          The main sources of wastewater are domestic and industrial.  In
 the case of domestic waste,  100 percent of the water in northern areas
 ends up as wastewater because there is very little lawn and garden
 watering or car washing.  This also applies for industrial or commercial
 wastes unless local experience or actual measurements indicate otherwise.
 An  exception would be the case of a cold storage-fish processing opera-
 tion or a cannery where a significant portion of the water may be used
 for cleaning floors and equipment and is discharged directly to the  ocean.
 A contrary example would be  the case where salt water was used for clean-
 ing and discharged to the collection system.   Infiltration and inflow
 allowances must be made for  buried lines in high groundwater situations
 or  where water  wasting is practiced.  These problems should be corrected
 before sewers and sewage treatment plants  are  designed.   Inflow and
 infiltration studies should  be performed so the decision can be made to
 either correct  the problems  or design a plant  to treat  the dilute waste.
 7.1.1     Domestic waste
          Water  use rates typical  to  cold regions were  presented in
 Section  3  and sewage design  flows  with peaking  factors  are presented in
 Section  9.   The values  presented  show that  sewage flows  can vary
 considerably.   They  are  lower  in  volume,  and higher  in  strength,  for
 camps  and  facilities with  low  water  use  plumbing fixtures.   Where water
 is wasted  during  the winter  to  keep  service lines from  freezing,  waste-
water  volume  can  be  extremely  high and  of  very  low strength.   There  is  no
 substitute for actually  monitoring sewage  flows,  or  at  least  water use
rates, before sewer  or  sewage  treatment  design  is  undertaken.

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                            TABLE 7-1.  CHARACTERISTICS OF WASTEWATER  COLLECTION  SYSTEMS
TYPE
Gravity
SOIL
CONDITIONS
Non frost
TOPOGRAPHY
Gently sloping
ECONOMICS
Initial construc-
OTHER
Low Maintenance.
                   susceptible or
                   Slightly frost
                   susceptible with
                   gravel backfill-
                   ing material.
                    to prevent deep
                    cuts and lift
                    station.
                   tion costs high
                   but operational
                   costs low unless
                   mus t go above
                   ground or use
                   lift stations.
                     High health  and  convenience
                     improvements.
                     Must hold  grades.
                     Flushing of  low  use  lines  may be
                     necessary.
                     Large diameter pipes necessary.
Vacuum
Most useful for
frost susceptible
or bedrock condi-
tions, but can be
used with any soil
conditions.
Level or gently
sloping.
Initial construc-
tion cost
moderately high
                                                          Operational costs
                                                          moderate
"Traps" every 100 metres.
Low water use.
High health and convenience
improvements.
Must have central holding  tank  for
each 30 to 50 services with  additional
pumps to pump waste  to treatment
facilities.
Can separate gray and black  water.
Uses small pipes.
No exfiltration.
Pressure
Most useful for
frost susceptible
or bedrock condi-
tions, but can be
used with any soil
conditions
Level, gently
sloping or
hilly
Initial construc-
tion costs
moderate.
Operational costs
moderately high.
Low water use if low water use  fixtures
are installed.  High health and con-
venience improvements.
No central facility necessary  units
are in individual buildings.
Number of services not limited.
No infiltration.
Uses small pipes.
Vehicle-Haul
Year-round roads
must be available,
Level, gently
sloping or
hilly.
Initial construc-
tion costs low.
Operational
costs very high.
Low water use and moderate health and
convenience improvements.
Operational costs must be subsidized.
Individual-Haul
Used with any
soil conditions
but boardwalks
are necessary in
extremely swampy
conditions.
Level, gently
sloping or
hilly.
Initial construc-
tion cost and
operational costs
very low.
Low usage by inhabitants and thus low
health and convenience improvements.

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                                   7-3
 7.1.2     Industrial waste
          Industrial waste  output is usually seasonal in cold regions.
 Canneries and  cold  storage wastes occur during the summer fishing season
 only.  Reindeer  slaughtering  and packing plant wastes have a high
 strength  and  flow,  but  usually only last for a couple months during the
 fall.  The amount and  strength of industrial wastes produced must be
 estimated using  information from temperate  areas for similar facilities,
 unless the facility can provide the information for their operation.  The
 kind and  size  of the solids present in an industrial waste may be a
 factor in waste  collection system design.  Screening or comminuting may
 be necessary before discharge to the sewer  system.
 7.1.3     Public  uses
          Nearly  all communities will have schools and hospitals or health
 clinics.   Estimates of  wastewater flows must be obtained for schools,
 considering the  number  of  students, the number of teachers living in
 quarters,  the  type  of  facilities provided (i.e., swimming pool, flush
 valve toilets  or regular gravity flush toilets, urinals, shower facili-
 ties), boarding  student dorms,  etc.  With hospitals or clinics, the
 number of  beds and,  again,  the  type of facilities provided should be
 determined.  It  may also be necessary to consider incineration or other
 special treatment of wastes that are dangerous to health.  Another public
 use waste  would  be  that from  laundromats.  These wastes are not much
 different  from those from  similar facilities in more temperate climates.
 See Section 3  for estimating  water  use to be expected at public
 facilities.  The strength  of  the wastewater is a function of the type of
water distribution  system.
 7.1.4    Water treatment plant  wastes
         Wastes  from water  treatment plants must be estimated if they
cannot be  measured.  The highest flows,  which would be from filter
backwashing, are usually known.   They can be very sporadic (not usually
continuous) and  may  require a holding tank  for flow equalization before
discharge  to the collection system.   Filter backwashing flows are low in
BOD but create a high chemical  and  hydraulic loading.   Consider the
effect of  the chemicals  on  the  collection line materials.  They can be of

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                                      7-4
high pH and/or very corrosive.  Consider electrolysis problems when
wastes are from a salt water distillation unit.  This can usually be
reduced by correct grounding and non-conduction fittings in piping
systems.  When plastic pipe is used corrosion and electrolysis are
usually not problems.
7.2       Individual Bucket Systems
          With a collection system relying on the individual users to
bring their wastes to a disposal point, the important considerations are
the types of containers in which the waste is transported and the
facilities at the point of discharge.
7.2.1     Hauling containers
          Containers used by individuals for transporting wastes will vary
from conventional oil drums to honeybucket pails.  They should be
cleanable so they can be washed or steam-cleaned and disinfected for
reuse (see Section 13).  The containers should be covered so the contents
don't splash out in the owner's house or throughout the community as they
are transported.  The containers should be sized for the way they will be
transported.  In many communities with no roads the children or women
will empty the honeybuckets.  Larger containers can usually be used in
the winter because they can be carried on sleds.  The summer is the
critical time because the swampy conditions around many coastal
communities will mean hauling by hand.  In this case, the pail or bucket
should probably not be larger than 10 litres, which would weigh about 10
kg when full.  If roads are present and individual vehicles can be used
year-round, larger containers may be desirable.  In many smaller
villages, 20-litre containers are readily available because gasoline and
white gas are purchased in them.  They are used for everything from
hauling water to patching holes in the roof.  In larger communities,
individuals use pickups or trucks to transport oil drums filled with
honeybucket wastes to a disposal site.  Individual honeybuckets in the
house are emptied into the oil drum which sits outside the house.
Sometimes the oil drum is emptied and returned to be refilled but
usually, unless cleaning facilities are available at the disposal site,
the drum is discarded with the waste.

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                                   7-5
7.2.2    Disposal  point
         The disposal  point  must  be  designed  to accommodate a wide
variety of  container  sizes and  be convenient  for people;  otherwise the
wastes may  not  be  deposited  according  to  facility design.  The disposal
point Gould be  a landfill site, a facultative lagoon or pond, a waste
disposal "bunker",  or  a  discharge point on  the side of a  building such as
a watering  point or central  facility (see Section 13) where the waste is
then transported to a  treatment facility  by pipes.
         Where  honeybucket wastes are  dumped  at a landfill site they
should be covered  daily  to prevent children,  dogs, and birds from getting
into them.
         If the wastes are deposited in a lagoon or pond  the dumping
point should be designed to  prevent  erosion of the lagoon dykes and yet
allow for easy  access  so the waste doesn't  end up all over the dykes
instead of  in the  lagoon.  A platform  with  a  hole out over the water is
satisfactory.   A major problem with  lagoon  disposal is the plastic bags
which are often used  as  liners in honeybuckets.  They are not bio-
degradable  and  should  not be deposited in the lagoon.  It will be
necessary to empty  their contents into the  lagoon and then deposit the
bags at a landfill  or  burn them.
         Waste  disposal  pits are  constructed  by cribbing  a hole in the
ground, similar to  a cesspool and covering  it with a platform containing
a disposal  hole covered  with a fly-tight, hinged lid (Figure 7-1).  When
the old pit is  full the  platform  is  removed and the bunker is covered
with the material excavated  from  the new  pit.  Most of the liquid portion
of the honeybucket  wastes will seep  out when  the surrounding ground is
thawed.  As with privies, waste pits are  not  a desirable  form of waste
disposal if the soil is  frozen fine  grained silts or when there is a high
groundwater table.  More modern methods such  as sewage treatment plants
or lagoons  are  desirable, but the pits at least reduce the serious health
problem of  having the  honeybucket wastes  dumped over a river bank or
around the  houses.
         The most satisfactory disposal for honeybueket wastes would be
at a central facility  or watering point where the wastes  are a small part

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                                  7-6
                          -
                     FIGURE 7-1.  WASTE DISPOSAL  PIT
of the total waste load to the facility.  The  treatment  would  be
accomplished by one of the methods discussed in Section  9.   A  fly-tight
closeable box, which is convenient to use, should  be  provided  on  the
outside of the building.  It must be vandal proof  and  capable  of  being
thoroughly washed down and cleaned daily.  Above  all,  it must  be
aesthetically acceptable and easy to use; otherwise,  it  will not  be  used.
         Disposal points must be centrally located  to  all dwellings  or
their chances of being used regularly are small.   The  distance that
individuals will haul wastes varies with many  factors.   Two  of the more
important considerations are training and education of the users, and  the
ground conditions over which the wastes must be hauled.  Experience
indicates that the number of individuals that  utilize  a  disposal  point
starts dropping off considerably when the distance exceeds 200 metres.
Also, the people tend to haul longer distances in  the  winter because  in
most communities, it is easier to get around and  snowmobiles can  be  used.
An extensive education program is invaluable in promoting  the  use of a
disposal point with individuals hauling their  own  waste.
         The type of waste dumped at a disposal point  eould  be an impor-
tant consideration in treatment plant design even  though the quantity (by

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                                   7-7
 comparison to  the facility wastes)  may be small.  The waste quite often
 contains  a high concentration of deodorizers such as formaldehyde and
 phenols,  which could affect biological treatment processes.  It also may
 contain plastic bags and other solid wastes and will be very high in BOD
 (up  to 1000 mg/L) and low in hydraulic loading.
 7.3       Vehicle-Haul with House Storage Tanks
          Community-haul  sewage collection deals with the collection of
 wastewater from each dwelling and its transportation by a community or
 contractor-operated  tracked or wheeled vehicle to a treatment and/or
 disposal  facility.
 7.3.1     Facilities  at pick-up point
          The facilities  at the individual user's dwelling or building can
 vary from simply emptying a honeybucket (as discussed under individual-
 haul above)  into a  tank  on a truck  (Figure 7-2), to a holding tank within
 the building from which  the wastes  are pumped  into the collection truck.
          If  the facilities in the building consist only of honeybuckets,
 the same  considerations  listed under individual-haul would apply.
 However,  most  modern vehicle-haul systems consist of a sewage holding
 tank located on or beneath the floor of the house into which the
 household wastes from sinks,  lavatories,  and  toilets drain by gravity.
 The tanks  are  then emptied into  the collection vehicle (Figure 7-3) by
 pumping.
          The efficiency  and operational costs  of this type of collection
 system are  dependent partly on the  sizing of  the holding tanks.  For most
 circumstances,  tanks should be around 1000 litres, but at least 400
 litres larger  than the water  storage tank provided [1,4].  In Canada,
household  tanks  as large  as 4500  litres have been used and it is common
 practice  to make  the sewage holding tank  up to twice as large as the
water storage  tank.   The  size  of  the collection vehicle and reliability
of the service  should  be  considered in  sizing  wastewater storage tanks.
 It is also  important to  provide  the structural support in the house
required  to carry this additional load.   The tank must be constructed
with a large manhole with  removable cover so it can be cleaned  and
flushed out at  least  yearly.   It  must be  well  insulated,  kept within the

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                         7-?
FIGURE 7-2.  TRUCK FOR COLLECTING HONEYBUCKET WASTES
             - BARROW, ALASKA
FIGURE 7-3.  TRACKED  SEWAGE  PICK-UP  VEHICLE
             - ARCTIC VILLAGE,  ALASKA

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                                      7-9
heated portion of the building and/or heat must be added using heating
coils or circulating hot water to prevent any ice formation.  In some
instances, the holding tanks have been buried in the ground beside or
beneath the houses (Figure 7-4).   In permafrost areas this is not
satisfactory and it is even necessary to add heat in areas where the tank
is buried in the active layer.  The tanks must be placed so they are
emptied from the outside of the house.
          The hose connections should be of the quick-disconnect type and
be a different size than that of the water delivery hose, to eliminate
the possibility of a cross-connection.  The pumpout connection at the
building must be sloped to drain back into the tank after pumping so
sewage does not drain outside the house or stand in the line and freeze.
The tanks must be vented into the attic or outside to allow for air
escape or supply as the tank is filled and emptied.  The same considera-
tions should apply to this vent as are discussed at the end of this
section under building plumbing.
          With any haul system, low water use plumbing fixtures (Figure
7-5) are necessary to reduce water usage.
7.3.2     Hauling vehicles
     The type of vehicle used depends upon the conditions at the
site.  Tracked vehicles should be avoided if at all possible because of
the much higher capital, operating and maintenance costs, and slower
speed compared to rubber-tired vehicles.  Typical costs of the vehicles
themselves are presented in Section 6 and Appendix D.  Instead of tracked
vehicles, four-wheel drive trucks with floatation tires can be used where
snow drifting and poor roads are prevalent.  Where there are no roads tracked
vehicles may be necessary.
          Vehicle-haul systems have higher O&M and replacement costs than
piped systems, and the vehicles have a short useful life (see Section
2.6.2).
          The vehicle must be equipped with a tank, pump and hoses to
contain and extract the wastewater (sample specifications are shown
in the Appendix E).  For collecting honeybucket wastes, the most prac-
tical tank is a half-round or round shape with a large manhole with a
hinged lid on the back in the flat cover (see Figure 7-2).  The flat top

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                                     7-11
allows for a lower emptying point.  Steps are provided on the side so the
honeybuckets can be carried up and emptied into the tank.  The trucks should
be kept as small and maneuverable as practical to get around to the houses.
Presently, tanks of 1000 to 5000 litres are used in small communities.  The
tank should be capable of being dumped at the disposal site unless the
contents are to be pumped into a sewage treatment plant.  At the rear, a large
valved outlet pipe of at least 200 cm (8 inches) in diameter is provided which
can be opened to empty the tank.  A small heater may be needed to keep the
short pipe and valve from freezing.  The truck exhaust can also be routed to
keep this valve warm and eliminate the need for a heater.  A full opening,
non-rising stem gate valve has proven best for this application as it must be
capable of passing solids such as plastic bags.
          The tanks on vehicles to
be insulated or enclosed in heated
be used with a pumpout system may have to
units on the backs of the vehicles (see
Figure 7-3).  These units will include the tank, pump, piping, and connection
hose.  The size of tank needed will depend primarily on the distance to the
disposal site and the sizes of the tanks in the houses [1].   Larger tanks will
reduce operating costs, particularly when the disposal site is distant.  Size
and weight of the vehicle, and thus the tank will be limited to the layout of
the community and the condition of the roads.   The truck must maneuver close
enough to the houses to pump out the tanks in a reasonably short time.
          The number of trucks needed in a given community will depend mainly
on the number of buildings to be serviced and volume of wastewater to be
collected [1,4]. Two methods of emptying the house tanks are being used.  With
one, a pressure tank is used on the vehicle.  The tank is held under a vacuum
using a small compressor and a three-way valve.  The contents of the house
tank are withdrawn into the truck tank under vacuum.  At the disposal point
the valve is turned to pressurize the tank, forcing the wastewater out (see
schematic in Figure 7-6).   The advantages to this method are that a compressor
is used instead of a pump, and there are no pipes containing sewage,   which
could freeze.  The other method is similar except that sewage pumps are

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                                   7-12
                                         -Clutch handle
           Negative pressure port
                      Vent to
                     | atmosphere
                           Valve handle
                                Positive pressure
                                relief valve
                                Fill and
                                discharge hose
                                     Positive
                                     pressure port
                                     Pressure gauge
                                     negative and positive
       Butterfly valve open
       while filling holding tank
     LJLJjl
                                                     Wastewater holding tank
                                                     on pumpout vehicle
     Butterfly valve open
     while emptying holding tank
 Filling holding tank by air suction
FIGURE 7-6.   FILLING AND EMPTYING PROCEDURE FOR  HOLDING TANK PUMPOUT  TRUCKS
Emptying holding tank by positive
          air pressure
used instead  of a compressor  and  the vehicle tank  does not have  to  be
pressure  rated.  The suction  hose must be long  enough to extend  from  the
house  to  the  most convenient  parking place for  the truck.  It should  be
at least  7.5  cm in diameter and  kept on a reel  so  it can be rolled  up
inside  the  heated compartment on the truck.  It must also be rugged
enough  that it can be dragged behind the truck  between houses, and  be
flexible  at low temperatures.
7.3.3     Disposal site
          The  disposal point should be in a heated  building with  a  "drive
through"  design to make  the unloading time as  short as possible.   The
building  should also provide  heated storage  for the vehicles while  not in
use or  when they're down  for  repairs.  Where the  disposal point  is  at a
landfill  or lagoon, a ramp  or splash pad or  something similar should  be
provided  to prevent erosion and  still allow  the vehicle to deposit  the
wastes  well within the  lagoon or landfill.   The same problems with
plastic bags  will be present  as  were discussed  under individual-haul.
          The  building in  which the vehicles  are stored and/or emptied
should  also be equipped  with  water for flushing and cleaning  the tanks.
Extreme care  should be  taken  to  prevent any  cross-connections.

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                                  7-13
7.4      Piped Collection Systems
         There are several variations of piped  sewage  collection  systems.
Normally, a conventional gravity system has the lowest life-cycle cost
and should be used whenever  feasible.  However, the  layout  of  the site
and/or the soil conditions may make a vacuum or pressure  sewage collec-
tion system necessary.  An additional advantage of a gravity system  is
that a freezeup seldom causes pipes to break.   The freezeup is gradual
and in layers, in contrast to pressure lines which are full when  freezing
takes place.
7.4.1    Design considerations
         When soil conditions do not allow burying collection  lines  (as
discussed in Sections 2 and  8), they must be placed  on or above the
surface of the ground.  In most locations, the  topography and  building
layout would dictate above-ground lines on pilings (or gravel  berms)  to
hold the grades necessary for gravity sewage flow.   Above-ground  lines
are undesirable because of transportation hinderance (see Figure  7-7),
high heat losses, blocked drainage, vandalism,  and the cluttered  look
they create within the community (see Section 8).  It  may be preferable
to use a pressure or vacuum  system so that the  lines can  be placed on the
ground surface (see Figure 7-8), to minimize the above problems.
         Sewage collection lines may be placed  in utilidors (see  Section
8) with other utilities, depending on the local circumstances. Utilidors
cost between $600 and $1700  per metre to construct,  depending  on  the
utilities included and the roads to be crossed  (see  Section 8).   Buried
pipelines cost (per pipe) between $100 and $300 per  metre to install,
depending on the excavation  conditions.  Above-ground  pipeline costs
depend on the foundation required.  If they can be layed  directly on  the
ground surface they cost $50 to $100 per metre, but  if they have  to  be
placed on pilings the costs  could run as high as $250  per metre.
Assuming the same design, heat losses, and thus O&M  costs,  of  above-
ground facilities are nearly three times as high as  for the same  line
placed below-ground because  of the greater temperature differential
between the inside and outside of the line.  Section 2 includes a more
in-depth discussion of the advantages and disadvantages of  above  or  below
ground facilities.

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                     7-14
!*
m
                 i^r^l


Jfi  i_ .   "tyfc,. <- .'*"

 A ^ **z^^ .^^si^V-> -
>^v..
 A
", 2*-"-.
a. ***  o
 FIGURE 7-7.  SEWAGE COLLECTION LINES ON PILING
              - BETHEL,  ALASKA
 FIGURE 7-8.   SMALL (0.4 m x 0.5 m) UTILIDOR  LAID DIRECTLY
               ON  THE TUNDRA SURFACE CARRYING  WATER,  SEWER
               AND GLYCOL LINES - NOORVIK,  ALASKA

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                                  7-15
         Sewage temperatures are also an important design consideration.
In camps or communities where the individual buildings have hot water
heaters, sewage temperatures usually range between 10 and 15C.
Where hot water heaters are not used and any hot water must be obtained
by heating water on a cook stove, sewage temperatures range from 4  to
10C.  A greater percentage of this heat will be lost between the
users and the point of treatment with a gravity system than with a
pressure or vacuum system.  The sewage is longer in transit and there  is
air circulation above the sewage in the pipes because they are not
flowing full.  It is often necessary to dump warm water at the ends of
little-used laterals in a gravity system to eliminate freezing problems
caused by the lines slowly icing up.  Also, a greater percentage of the
heat will be lost if the lines are above ground.  Sewage heat losses will
not vary considerably from summer to winter with buried lines, but  there
can be a considerable variance in above-ground lines.  (This is discussed
in detail in Section 8.)  Thus, the worst condition is to have gravity
sewage collection lines placed above-ground.
7.4.2    Conventional gravity collection lines
         If lines can be buried and the layout of the site is sloping  a
gravity sewage collection system will have lower O&M costs than other
types of systems.  Initial construction costs will usually be lower
unless there is considerable rock to excavate.  Costs for rock excavation
range between $50 and $75/m3 in the N.W.T. (1977).
         The most important design consideration with gravity sewers is
the minimum grades necessary to ensure adequate velocities in the pipe-
lines.  The following minimums should be used with stable ground condi-
tions (not frost-susceptible):
a)       Main collection lines
Nominal
Pipe Size
(inches)
6
8
10
12
Minimum Slope
(percent)
0.6
0.5
0.4
0.3

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                                     7-16
             14                0.22
             15                0.17

b)        Building service lines
           4 or 6              1.0

          If soil stability is unsure (i.e., a small amount of settling or
heaving is likely), use a minimum slope of one percent for all collection
lines and backfill with non-frost susceptible sand or gravel at least 30
cm at the bottom and sides of the pipe (Figure 7-9).  The 4-inch service
lines should be placed the same way with a two percent minimum slope.
Higher slopes than those above should be used if possible because the
longer the sewage is in the collection system, the more heat it will
lose.  In small communities minimum sewage collection line sizes could be
6 inches instead of the normal 8 inches.
          Lines should be placed deep enough to prevent damage from
surface loadings and the possibility of future expansion should be
considered.  A minimum of 0.7 metres of bury is usually recommended but
less  could be allowed in communities with no roads or vehicles.  Other
depth of bury considerations are given in Section 15.
          Storm water should not be included in sewers in cold regions.
It  can be cold, lowering wastewater temperature, it overloads treatment
facilities hydraulically, and it usually contains sand and grit which
deposits  in  collection lines.   Insulated pipe should always be used
unless lines can be buried well below the active layer and not in
permafrost.
          In addition to  the  steeper slopes  listed  above, provisions
should be made  to  readjust the  slope of a line  if it traverses an  area
where movement  is  likely.  With lines on piling this has been done by
placing blocks  between the piling  and the pipeline, acting as shims.
They can  be  removed  or added  to readjust  the slope.  If  the  lines  are  in
a utilidor  they can  be suspended  from the utilidor  roof  with adjustable
turnbuckles  or placed  on  adjustable yokes or supports.
          Manholes  require protection  from  frost  heaving or  jacking  forces
by use  of plastic film to break the  soils bond  to the  manhole (see Figure
 7-10).   They should  also  be  insulated with  a minimum  of  three inches of
 styrofoam or urethane  around  the  outside.   The  insulation reduces  heat

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                                         7-17
             Hand tamped backfill
           Bedding gravel or sand
                     to top of pipe

                               Pipe

                                                                     Variable
                                                 Compacted
                                                    backfill
                                                                      I: 100
             FIGURE  7-9.   TYPICAL SEWER AND WATER BEDDING  DETAILS
     150 Minimum
3 Wraps of 6 mil polyethelene film

1100 Corrugated aluminum pipe
        Field foamed urethane
                  Concrete
     Corrugated metal pipe
                                                                                   Variable
                                      25
                                      Grout seal
                                        Field cut bore to fit pipe size
             _
      'oarnecl urethane
50 x 100 Support bolted to culvert with 50 x 50 angle clip
                            j^^cfrrrVTrV^^'^'^^ncreteT^^'l 50 Mln /;;^Kjp-,,.,,,,-,-,,,:,,,. ,,,,..-
                       FIGURE  7-10.   SEWER SYSTEM MANHOLE

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                                 7-18
losses and provides an additional  safety factor  against  soil  bonding  and
frost jacking.  An insulated  frost cover to  further  reduce  heat  losses
should be provided inside.  Manholes must have a firm  foundation to
prevent settlement.  This could mean pilings  under  the manhole or, at
least, over excavation and backfill with gravel.  The  invert  should  be
poured over insulation to reduce heat  loss downward  which could  thaw
unstable permafrost and cause  settlement.
         Conventional pre-cast concrete manholes are very expensive  to
ship and install  in remote northern areas.   Bolted  corrugated aluminum
manholes can be used in nontraffic situations.   They can be nested during
shipment and air  freighted in  small planes.   Manholes  should  be  placed
every 90 m or at  any changes  in grade  or alignment.  To  reduce heat
losses, 107-om diameter manholes are used as  a minimum in aretic areas.
Also, solid manhole covers without holes should  be  used  so  that  surface
water does not enter the manhole.  The lids  should  be  looked  down to
prevent the deposit of rocks  and garbage in  the  manholes.  Gravity sewer
lines should be thoroughly flushed out each  summer,  ideally when the fire
hydrants are being cleaned and flushed.
         Cleanouts, as they are known  in temperate  climates,  should  be
used with caution.  They are  susceptible to  frost jacking and hard  to
protect (see an example in Figure  7-11).   In  place  of  a  cleanout on  a
sewage collection line it is  better to use a conventional manhole.
         A special manhole has been developed in the N.W.T. that contains
hydrants and valves for the water  line and an air tight  cleanout on  the
inlet and outlet  sewer lines  for rodding and  flushing.  (See  Section 6).
One must be sure  not to create a cross-connection with a manhole
containing water  line appurtenances.
         As mentioned earlier self-flushing  siphons may  be  required  at
the end of long,  little used  laterals.  They can be set  to  dump a given
quantity of warm  water at different intervals.   The slug of warm water
traveling down  the  sewer  lines will eliminate any glaciering  which may
have built up because of  slow trickles of  water  from normal use.  The
flushing also scours solids which  may  have been  deposited because of low
flows.  They  should not be  used  unless absolutely necessary as they waste
water and create  an additional O&M cost.   It is  better to lay out the

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                                       7-19
               '::?f:-\:::r:?-^^
                  .\- .  '.'.  150 to 300 if under travelled roadway
                     ''
                                                 Cast iron frame
                                                 and bolt-down cover
                                                 with lift hole
                Gravel backfill;;/?
                Urethane insulation

                Corrugated metal pipe
                      Wrap with 3 layers of
                      6 mil polyethelyne film
                    FIGURE 7-11.   SEWER CLEANOUT DETAILS
                                                                      Sewer pipe
                                                        11000 Manhole
From water main
 Valve and vacuum breaker
..i-BW^ff&j^/j^&V^jjI^^/y
                                                                        Overflow and flush well



                                                                        150 x 200 Tee  wye


                                                                           To sewer
                                                        200 to 150  Reducer

                                                        125  Siphon
                    FIGURE 7-12.   SINGLE  LINE SIPHON

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                                    7-20
sewer  system so there  is at least one  large user near  the end of each
lateral  to eliminate  the need for flushing.  They can  be constructed  in a
building  or in a manhole as shown in Figure 7-12.   Again, oare must be
taken  not to create a  cross-connection between the  water and sewer  systems.
          Figures 7-13  and 7-14 show  typical service line connections  to a
building  for a cold region gravity sewage eollection system.  They  should
slope  at  least one  to  two percent to  the oolleetion main, depending on
soil  stability.  Of the two examples  shown, the method of going  through
wall  is  preferable  to  going through  the floor.  The former will  allow for
more  movement of the  house without damage to the sewer service line and
also  permits all house plumbing  to be  kept above the house floor  (this
will  be  discussed  later).
          The preferred method for thawing sewage eollection lines  is  to
push  a small diameter  plastie line through the frozen line while
circulating warm water.  A complete  discussion of  thawing lines  is
contained in Appendix  F.
          Sewage lift  stations will be  discussed later in this section.
They  can be an  important part of a gravity system.
          Wood box with removable
          lid screwed on with
          wood screws
            Filled with polystyrene
            or fiberglass insulation
             To building sewer
                                                 150
                                                Minimum
                                          Hose clamp
90 0x 500 Flexible hose
75PVC
100 x 75 Reducing bell coupling
Band
                 Filled with polystyrene
                 or fiberglass insulation
             Flexible rubber dram housing
                          Band
               Approximate ground line
                      __^^-.
                      ' o'-;~
       Corrugated metal  pipe
       filled-in or smooth to
       reduce frost jacking
                  FIGURE  7-13.   HOUSE SEWER  WALL CONNECTION
          Box-

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                                   7-21
                                              To building sewer
      Detail
                                                         Plug
                                                         Calking
                                                         Building floor
        Flexible rubber drain housing
             Filled with polystyrene
             or fiberglass insulation
      Approximate ground line
                      ..  .-. . *
                      o. :-o-  :
                                            All temperature grease
                                            900 Flexible rubber hose
                                            75 PVC
                                            100x75 Reducing bell coupling
                                            Band
                                                  r- v; -..-
Corrugated metal pipe
(Filled-in or smcfe'dt^l
 to reduce frost   
 jacking)        To Sewer mam
   FIGURE 7-14.  HOUSE  SEWER FLOOR CONNECTION
                                                         1 00 PVC
7.4.3     Pressure sewage collection systems
          If  soil conditions and  community layout make a gravity
collection system not practical  a  pressure or vacuum system  may be
considered.   Pressure sewage collection systems usually have sections
that operate under gravity, and  vice-versa.  A small pump-grinder unit in
or near  each building provides the  motive force for the pressure system
(see Figures 7-15 and 7-16).  The  largest advantage is that  it is not
necessary to maintain grades.  Pipelines or utilidors do  not have to be
on piling or up off the ground.  They can be at the surface  or buried and
small movements due to frost heave  or thawing will not affect operation.
There can be no problems with infiltration of groundwater because the
lines are under pressure; however,  a leak in the sewer line,  if not
repaired,  could contaminate other  lines within a utilidor.   Construction
costs would  probably be lower than  either a gravity or vacuum system, but
O&M costs would be greater than  for a gravity system because  of the pump-
grinder  units in each building.  Smaller collection lines can also be
used with a  pressure system and  normal  elevation differences  throughout a
community will not affect operation.   Pressure collection lines can be

-------
                            7-22
Building gravity sewage piping
           Storage tank ^fr

          Pump-grinder ^<


                On-off level sensor

                  Overflow level sensor
                                                    Drainage field
                                     Existing septic tank
                                  I	1
     FIGURE 7-15.  TYPICAL PRESSURE SEWER INSTALLATION
     .

  -^v'V:-.:l3
.   -o  ...?:vp.v.:-;.'


k 	 ixl
;; Bathroom
i
J
gC=3


R

-*-H










To pressure :/>v'..;..;:; -.o.-.;. -. : ?. . .
3'  *  '   ' P-' '? *
'.'-''l?y::'/''<>:
                      Pump-grinder unit
      FIGURE  7-16.  TYPICAL PUMP-GRINDER INSTALLATION

-------
                                    7-23
sized to handle any number of connections.  Another  advantage,  in a remote
community, is that, with  the pump-grinder unit  in  each  building,  the O&M
costs for the majority of the sewage collection system  will  be  paid by
the building owners as they pay  for the electricity  and maintenance of
their pump.  This essentially eliminates billing and collection of
operational costs from users and  if a unit  fails because of  lack of O&M,
only one user suffers.
         The collection lines must be sized to  maintain a minimum of one
metre per second scour velocity.  The minimum size collection line is
1-1/4 inch, which would be the size for one unit.  If more houses are
added than were originally planned for, velocities will increase  down the
line.  The effect of  this velocity increase is  an  increase in head loss
which, within reason, is  not a problem because  the individual pump-
grinder units have a  very flat pumping rate vs  head  curve.  Pressures
should be held below  275  kPa (40  psi) in the layout, and the lines should
be slightly undersized (higher velocity) rather than oversized  if the
correct size (for one metre per  second) is  not  available.  In the design
of a pressure system, an  assumption that 33 percent  of  the pumps  will be
operating at once is  recommended  for sizing pipes.   The collection lines
should be constructed to  drain to low points if the  system has  to be shut
down during the winter.   In low  flow conditions where heat losses may be
extreme (such as at night in the  winter in  an above-ground situation) or
where the minimum scouring velocity (one metre/second)  cannot be  met, the
pressure collection lines should  be looped  back to a water source so warm
water can occasionally be pumped  through the lines.   Air relief valves
should be installed at major high points in the line.
         The pump-grinder units  can be situated in each building  or
several buildings could drain into one unit by  gravity  (like the  system
in Bethel, Alaska [2]).   The units should be designed to pump against the
design head in the main plus a 40 percent overload (with 33  percent of
them operating at once).  Each unit should  have complete duplication of
controls, sump pumps, and pumps  or compressor,  for standby.   The  extra
unit would take over  if the primary unit is inoperable  and,  at  the same
time, set off a warning device (audible and visual)  to  alert the  operator

-------
                                   7-24
that repairs are required.   Standby power should  be available  in  case of
a power  outage for units  serving several buildings.  The pumping  units
should be  well insulated  and installed on a  stable foundation  if  they are
placed outside or in the  ground.  As with manholes they must be  protected
from frost jacking forces.   Double check valves  should be provided  on
inlet and  outlet to prevent  backflow.  This  is especially important for
pneumatic  type pump stations, discussed later.   Also, weighted check
valves have proven more  satisfactory than spring  loaded valves.
          The pump-grinder units designed to  serve individual buildings
are equipped with positive displacement pumps  which have a nearly
constant pumping rate  over a wide range of heads  (Figure 7-17).   The
grinder  unit reduces all  foreign objects to  6.5  mm size before they go
into  the pump.  The unit  must be able to handle  items flushed  down  the
toilets  such as rook,  wash rags, utensils, etc.   Positive displacement
pumps also require a lower power input to purge  the system of  air pockets
which could form.  The units must be small and  light enough  that they ean
be easily removed from the sump and repaired while the standby unit
continues to operate.
      Grinder pump
 typical performance characteristics

400
                                                   1000 Inlet
                                                     Cover
   
  CD 5
  3 S
  2 g.
  15 
  II
                                                                0
                                                                  J	I
                                                                 0 40 80 120 160 200
                                                                      Number of
                                                                  grinder pumps connected
                                                     Motor breather check valve
                                                       32 0 Discharge pipe
                                                Check valve and
                                                anti siphon valve
          "0  2 4 6 8 10 12
        Discharge (L/ s), Input power (W < 10
         and Input current (amps at 240 VAC)
         FIGURE  7-17.
                PUMP-GRINDER  CHARACTERISTICS  (adapted from
                Environment/One Corp. Ltd.)

-------
                                  7-25
         With a 750-watt  (1 hp)  pump-grinder  unit  and  a water use rate of
190 L per person/day  (50  gpcd),  the  pump would  operate only about three
times per person per  day  with  each operating  period  lasting about one
minute.  Thus, a five-person family  would  use about  0.5 kWh a day.  At
25fc/kWh, this would only  amount  to about $3.75  per month per family for
electricity.
         The sump  or  tank from which the pump draws  must be designed so
that it is cleaned by scouring as the  pump operates.   The outlet check
valves should be located  in a  horizontal run  to prevent solids from
settling out in them  when the  pump isn't running.  Pressure sensors
should be used to  control pumps  and  alarms because rags and grease tend
to foul float switches.   The sump should be sized  (450 to 570 litres) to
provide several houses with storage  in  case of  a temporary power outage
or other problem.  It is  recommended that  they  be  constructed of
fiberglass or plastic for protection from  corrosion.
         Low water use fixtures  should  be  used  with  pressure systems
whenever possible  (see Figure  7-5).
         The pump-grinder units  and  any compressors, pumps, etc. in
larger lift stations  should be supplied with  low voltage protection and a
relay that will stop  the  motors  in case of a  major voltage fluctuation.
This device would  also protect the motor under  a locked rotor condition.
         The pressure system can also  be modified  by using conventional
submersible sewage pumps  in holding  tanks  at  each  building.  The tanks
are similar to septic tanks where the  solids  settle, biodegrade
anaerobically, and are pumped  out by truck occasionally.  The submersible
pump pumps the relatively clear  effluent into the  pressure sewer lines to
a treatment facility.  Some of the advantages of this  type of operation
are:
         a)  Problems with the grinder  on  the pump plugging up are
             eliminated.
         b)  There are no solids to  settle in the  collection lines.
         c)  The treatment facility  Is  not as complicated as for
             conventional  sewage.

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                                 7-26
7.4.4    Vacuum sewage collection systems
         As with pressure systems, a vacuum sewage collection  system  is
sensible only if soil conditions and community layout make  a gravity
collection system not feasible.  The vacuum sewer system  is detailed  in
Figure 7-18.  Toilet wastes, with a small amount of water,  are trans-
ported in the pipes by the differential pressure between  the atmosphere
(air admitted to the system with the flushing action) and a partial
vacuum in the pipe created by a central vacuum pump.  The flow conditions
are slug-type, but the friction in the pipe breaks down  the water  slug.
To reform the slug flow, transport pockets are required  at  intervals  of
about 70 to 100 m [3,5].  Vacuum systems are not limited  to holding grades,
but are limited to 4.5 to 6 metres in elevation differences because  they
are operated at 56 to 70 kPa (8 to 10 psi) vacuum.  The  vacuum toilets
(Figure 7-19) only require 1.2 litres of water to flush  and the collection
lines are small (2").  The requirement for transport  pockets (traps)  is  a
disadvantage of the vacuum system.  The traps will have  liquid standing
in them for extended periods of time so they must be  inside a  heated
utilidor or be well insulated.  They should also be provided with  drains.
Vacuum systems are limited to 30 to 50 services on a  given  collection line.
         Leakage out of  the sewage collection lines is  essentially
eliminated, and there is little possibility of sewage contaminating  a
water line  in a utilidor.  The need for house vents and  P-traps, with the
freezing problems that accompany them, is also eliminated.
         Vacuum systems  can also be used  to collect  sewage  in  large
apartment buildings.
         The vacuum system was developed  in Sweden.   Manufacturers and/or
distributors [6,7] in the U.S. and Canada  should be contacted  to obtain
the latest  design standards as improvements are being incorporated
continuously.
         The collection  line  sizes will depend on  the number  of fixtures
on a  line and  the estimated number which  will be operating  simultaneously.
Usually 2 to 2-1/2 inch  lines  are  used with  the  traps dipping  at least
one and one-half  pipe diameters.   Tests have  shown  that head  losses
increase about  3.37 kPa  (one  inch  of mercury)  for  each  300  m of collec-
tion  line velocities of  4.5 m/s or less.   Because  the lines carry a

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                            7-27
  Vacuum pump
     v.  Air 
                       Vent
                                          Bath
                              Grey water valve
                       Service liquid tank
                       Transport pocket
                              \\
   t;      One-pipe vacuum main

Vacuum  collection tank
  . ) Pressure pump
                                                  Vent
                                                    Sink
                                                          Vacuum toilet
                                               Vacuum toilet
    To treatment and disposal
                                    \_
Grey water valve
       FIGURE 7-18.  ONE-PIPE VACUUM SYSTEM SCHEMATIC
      Vacuum toilet
                                                   Flushing mechanism
           Vacuum main
                                               Discharge valve
      FIGURE  7-19.  VACUUM TOILET

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                                 7-28
combination of air and water, head losses are  nearly  impossible to
compute.  However, when going uphill,  the increase  in head  loss is only
about 20 percent of the actual elevation increase.  Most  fixtures will
not flush if there is less  than 41 to  48 kPa (6  to  7  psi) vacuum in the
collection lines.  Thus, if  several are flushing  simultaneously and the
vacuum drops to 41 to 48 kPa, additional fixtures will not  flush until
the vacuum builds back up.   Grey water (sink,  shower  and  tub wastes)  can
be separated from black water (toilet  wastes)  for treatment purposes  or
water reuse, by having the  toilets on  a different collection line than
the grey water fixtures.  In low use lines  where  it is not  desirable  to
have sewage stand in the traps for extended periods,  an automatic or
timed valve can be installed to bleed  air into the  end of the line and
keep the wastewater moving.  Full opening ball valves should be installed
approximately every 60 m so  that sections of the  lines can  be isolated to
check for leaks or plugs.
         A collection tank  is located  at the end  of the collection lines.
The tank is held under a vacuum at all times by liquid-ring vacuum pumps
which must be sized to evacuate the air and liquid  admitted to the system
by the users with a safety  factor of two.   In  Noorvik, Alaska, the design
figures used were six flushes per person per day  for  the  toilets and  115
litres per person per day for sinks and showers [3],   For 50 houses,
pumps were selected which were capable of evacuating  1.8 m  / minute
at a vacuum of 53 kPa (16"  of mercury).  The collected wastes are then
pumped out of the tank to the treatment facility  using conventional
centrifugal pumps.  They must be designed to pump with a  negative suction
head equal to the maximum vacuum under which the  tank must  operate.  The
collection tank is sized similar to the pressure  tank in  a  hydro-pneumati
system.  One-half of the tank capacity is used for  liquid  storage and thee
other half is space (vacuum) serving as a buffer  for  the  vacuum pumps.
Several alarms should be included in the tank  to  give warning of high
levels of sewage in the holding tanks, low  incoming sewage  temperature,
and low vacuum in the system.
         The plumbing fixtures in the  building are  the third important
part of a vacuum system.  Grey water valves (Figure 7-20)  collect water
from the showers, tubs, sinks, and lavatories.  These individual fixtures

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                                  7-29
                                 Atmospheric air
                      Vacuum
                                        Pneumatic connection
                                                Sensor-timer
            Atmospheric air
                3-Way valve
Rubber sleeve
Vacuum chamber
                Check valve
               Outlet (vacuum)
                      FIGURE 7-20.  GREY WATER  VALVE
are conventional  but the addition of water  use  restricting devices is
recommended.   The grey water valve is activated by pressure from water
upstream  in  the  fixture drain line through  a small pressure-operated
diaphragm.   This  diaphragm is mounted in a  tee  just  upstream from the
valve.  As grey water drains from the fixture,  it  hits the closed valve
and backs up  against the diaphragm, activating  it  and allowing the vacuum
in the collection main line to open the valve.   The  length of time the
valve is  open is  controlled by a timer.  The cycle will continue until no
more grey water  flows into the line and the fixture  is empty.  The grey
water valves  allow equal parts of air and liquid to  enter the system
(e.g., 115 litres of waste and 115 litres of air per person per day in
Noorvik).
         Vacuum  toilets resemble conventional  flush  valve toilets (see
Figure 7-19). They are activated by push buttons  which expose the waste
in the bowl  to the vacuum in the main.  The button activates the
discharge valve and a water valve at the same  time.   The water valve
allows about  1.2  litres of water from the water system to enter the
toilet bowl  for cleaning purposes.  The discharge  valve closes shortly
before the water  valve, allowing a small quantity  of water to remain in

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                                 7-30
the toilet.  The toilet discharge valve allows 100 parts of air  per one
part of liquid into the system or 120 litres of air per flush.   The
fixtures have been relatively trouble free at Noorvik, Alaska, for the
three years that system has been in operation [3].
7.4.5    Other collection systems
         Other collection systems have been investigated, such as the
possibility of using oil or antifreeze solutions to transport the sewage.
However, none of them have proven feasible for a community or camp
collection system.
7.4.6    Piped collection system materials
         (See Appendix A).
7.4.7    Pressure and alignment testing of sewer lines
         Pressure sewer lines should be tested as any pressure water line
would be.  If using water or liquid, use 1-1/2 times the working
pressures with an allowable loss of 10 litres in 24 hours.  If using air,
use 1-1/2 times the working pressure with an allowable loss of 103 kPa
in 24 hours.  Great care must be exercised when using compressed air
because of the possibility of explosion.  Air testing must be used at
below freezing temperatures.
         Standard tests are satisfactory for air testing gravity sewer
lines.  An exfiltration test for water-tightness should be used  where
gravity sewer lines are above the watertable.  The test should be made
between manholes by blocking the lower manhole to a depth one metre over
the top of the valve.  The leakage should be measured by checking the
drop over a period of two hours minimum.  The maximum allowable
infiltration or exfiltration, including manholes, should not exceed 190
litres per 24 hours per 300 metres of sewer per 25 mm of pipe diameter
for each isolated section tested.
         The alignment and grade of the completed sewer main or  one under
construction can best be checked by lamping the line.  This operation  is
performed by simply shining a light through the line  from a manhole and
observing the alignment.  Horizontal and vertical curves in sewer mains
are not recommended but are permitted under most codes.

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                                  7-31
7.5      Lift Stations
         Sewage  lift  stations  are  used  mainly with gravity collection
systems but could  be  used  with pressure sewage collection systems, and
even vacuum systems (to  pump  the waste  from the collection tank to the
treatment  facility).
7.5.1    Types
         Table 7-2 presents the advantages  and disadvantages of each type
of lift station.
7.5.2    Cold regions adaptations
         The following modifications  should be made to conventional lift
stations in cold regions.
         The outside  of  the station  should  be insulated with at least 8
cm of urethane or  styrofoam with an  outer  protective covering to protect
the insulation from moisture.   Insulation  should be placed underneath the
station to prevent settling due to the  thaw of frozen ground.  Visqueen
(plastic) or some  other  bond  breaker  should always be used to reduce
frost jacking in the  active layer.  If  thawing and settling under the
station is anticipated,  pile  foundations extending well into the perma-
frost are  recommended.   All stations  must  be attached to concrete slabs
to provide sufficient weight  to overcome the buoyancy of the station
itself if  it were  completely  submerged  in water.  Pressure coupling
(flexible) type  connections are recommended at the inlet and outlet of
the stations to  prevent  differential  movement from breaking the lines.
         A lift  station  should never  be installed in the ground without
immediately placing the  heater and dehumidifier into operation.
Condensation from  cold surrounding ground  could corrode the controls and
electrical connections.
         Alarms  are an absolute necessity  in any lift station.  All
critical components,  such  as  pumps and  compressors, should be duplicated
in each station.   The controls should allow the operator to specify
operation of a pump or compressor, with the identical standby unit taking
over if one or the other does  not  start.  An alarm (both visual from the
surface and audible) would then warn  the operator that one unit is
malfunctioning.  The alarms can also  be set for the temperature and water
level in the station (to warn  of a sump pump malfunction).  These alarms

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                                     7-32
     TYPE
TABLE 7-2.  TYPES OF LIFT STATIONS

        ADVANTAGES
     DISADVANTAGES
1.   Submersible
2.   Dry Well
3.   Wet Well
4.   Suction Lift
5.   Pneumatic
      Ejector
   Low initial cost; low
   maintenance requirements;
   does not require installa-
   tion of appurtenances
   such as heaters, dehumidi-
   fiers, sump pump, etc.;
   station can easily be
   expanded and increased in
   capacity; available for
   wide range of capacities.
   Little of the structure
   is above ground so
   heat losses are greatly
   reduced.

   Pumping equipment located
   away from wet well; low
   cost per gallon capacity;
   good reliability; high
   efficiency; desirable
   for large installations;
   easily maintained.

   Low initial cost; high
   efficiency; wide range
   of capacity available
   Good reliability; avail-
   able for wide range of
   capacity.
   For low capacity (40 gpm
   or 150 L/minute) low
   head, for short distances;
   generally nonclogging,
   380 L/minute (100 gpm)
   maximum usually.
Difficult to make field
repair of pump, requires
specialized lifting
equipment to remove
pump.
High initial costs;
requires larger
construction site.
Requires explosion proof
electrical motors and
connections; difficult
to maintain pump.

Suction lift limited to
4.5 metres; decrease in
priming efficiency as
pump ages.

Somewhat more complex
than other types of
stations; high mainten-
ances; low efficiency.

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                                  7-33
should be tied back  into  a  central  alarm panel  in the puraphouse or
operator's house,  and  can be  connected  to the  operator's and/or the fire
or police department's phone.   Standby  electrical power should be
provided for each  major lift  station.
         Inlet screens must be  provided to remove items that would clog
pumps or check valves. Each  lift station should be checked by the
operator and the inlet screen cleaned daily.   Submersible types or those
without a heated dry well in which  to work should be housed in a heated
surface structure  with the  electrical controls  and alarms.   All entrance
manholes must extend above  the  ground surface  sufficiently  to be above
any flooding or snow drifts.  Also, manhole entrances or building
entrances must be  kept locked.   All pumps or motors should  be supplied
with running time  meters  for measuring  flow rates; conventional water
meters do not work properly with sewage.   Corrosion protection should be
provided for the metal shell in each station.   Sacrificial  and corrosion
protection systems do  not work  well when  the ground surrounding the anode
or lift station is frozen.
7.5.3    Force mains
         Force mains are  pressure lines into which the pumps in the lift
station discharge.  They  should be  designed to  have scour velocities
during pumping (21/2  to  3  ft/sec or 7.5  to 9 m/s) and to drain between
pumping cycles.  If  this  is not possible  the line must be placed in a
heated utilidor or heat traced  in some  way. Another option would be to
time the pumping cycle so the sewage stays in  the line for  a calculated
period, and to size  the holding tank at the lift station to hold at least
the volume of the  force main.   The mains  should be pressure tested and
they should meet all the  criteria of pressure water transmission
pipelines (see Section 3).  If  they empty into  a manhole, the entrance
should be at least 0.7 m  above  the exit line.
7.6      Building  plumbing
         Service lines and  their connections to the buildings were
discussed earlier.  The special  plumbing  needed with vacuum sewers was
covered in the section dealing  with vacuum collection systems.

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                                  7-34
         The use of floor-mounted, rear-flushing toilets keeps all waste
plumbing lines in the walls of the building and out of  the  floors (10  cm
above the floors).  These toilets are readily available.  Wall-mounted,
rear-flushing units are not recommended unless the wall is  reinforced
because the wall supports the entire weight of the toilet and the user.
The floor-mounted, rear-flushing units must be carefully installed;  over
-torquing the flange bolts will crack the base.  Examples of floor-
mounted, rear-flushing toilets are the "Yorkville" by American Standard
or the "Orlando" by Eljer.  Tubs should be placed upon  blocks so the
entire trap and drain is 10 cm above the floor.  This allows the tub to
drain into the toilet discharge line in the wall.  All  fixtures should be
placed on inside walls which are warm on both sides.  If possible, the
sink should be placed on the opposite side of the bathroom  plumbing  wall
to reduce the length of drain lines.  All fixtures and  lines should  be
installed so that they can be drained or otherwise protected from
freezing.  Drainable p-traps should be used and the user should be aware
that antifreeze solution should be added to his toilet  if there is a
danger of freezing.  Stop and waste valves should be provided at all low
points in house water supply lines.  Home owners must be trained to
maintain the facilities after they are installed.  They need to know how
to order parts, how to repair leaky faucets and toilets, and what not  to
flush down toilets.
         House vents frequently frost over in cold weather.  They should
be constructed of low conductivity material and should  increase in size
as they go into the unheated attic.  One and one-half inch  vents should
be increased to 3" and 3" to 4" and insulated in extreme circumstances.
7.7      Typical Construction Costs
         Table 7-3 gives estimates of 1977 unit construction costs.
7.8      References
1.   Gamble, D.J. and Janssen, C.T.L., "Evaluating Alternative Levels  of
     Water and Sanitation Service for Communities in the Northwest
     Territories", Canadian Journal of Civil Engineering, Vol. 1, No.  1,
     1974.

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                                     7-35
     Item
TABLE 7-3.  UNIT CONSTRUCTION COSTS (1977)

       Cost in Place*                     Remarks
Buried Utilidors
On-surface

Above-surface
Buried
 Pipeline

Rock excavation

Permafrost
 excavation

Normal Excavation

On-surface
 Pipeline

Above-surface
 Pipeline

Sewage grinder
 pump and sump

Manholes

Lift stations
Tracked hauling
  vehicle (2250 1)

Truck hauling
  vehicle (4500 1)

Vacuum toilet
 fixtures
 (plumbing)
       $400 to $l,200/m




       $200 to $300/m

       $600 to $l,700/m



       $90 to $300/m

                   3
       $50 to $75/m
                   3
       $40 to $80/m

                   3
       $20 to $30/m

       $60 to $100/m


       $120 to $300/m


       $3,200


       $1,500 to $2,000

       $18,000


       $45,000


       $25,000


       $2,600
Does not include excavation.
Depends on how many lines
are included.
Depends on backfill material.

Depends on lines included

Costs depend on foundation
(piling, etc.).
Depend on lines included.

Does not include excavation
Depends on Backfill material.
Depends on water content and
time of year excavated.
Depends on foundation
(piling, etc.).

Two pumps in sump.
Does not include excavation

Depends on size, does not
include excavation

With tank, etc.
With tank, etc.
In existing house.

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                                  7-36
Table 7-3.  (CONT'D)
     Item
Cost in Place
                                                     Remarks
Refuse packer
unit on 1-1/2
ton truck
Low water use
toilet
Plumbing a
house
Waste disposal
bunker (cribs)
House holding
tanks
$30 000

$2200

$2100
$800
$3500


In existing house.

Toilet, sink and lavatory.
Includes fixtures.
Includes excavation.
5' deep x 6' x 6'
Water and waste
* All costs vary with  transportation  (see  Section  2).   Those  costs  given
  are representative for mid-arctic conditions.

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                                  7-37
2.   Ryan, W.L. and Rogness, D.R., "Pressure Sewage Collection Systems in
     the Arctic", Proceedings of Symposium on Utilities Delivery in
     Arctic Regions, Report no. EPS 3-WP-77-1, Environmental Protection
     Service, Environment Canada, Ottawa, 1977.

3.   Rogness, D.R. and Ryan, W.L., "Vacuum Sewage Collection in the
     Arctic: Norvik, Alaska - A Case Study", Proceedings of Symposium on
     Utilities Delivery in Arctic Regions, Report no. EPS 3-WP-77-1
     Environmental Protection Service, Environment Canada, Ottawa, 1977.

4.   Cadorio, P.M. and Heinke, G.W., "Draft Manual for Trucking
     Operations for Municipal Services in Communities of the N.W.T.",
     Publication of Dept. of Civil Eng., Univ. of Toronto, Oct. 1972.

5.   Averill, D.W. and Heinke, G.W., "Vacuum Sewer System", Indian and
     Northern Affairs Pub. No. QS-1546-000-EE-A, Information Canada,
     Sept. 1974.  Also available from Dept. of Civil Engineering,
     University of Toronto.

6.   Colt Industries, Beloit, Wisconsin 53511, U.S.A.

7.   Vacusan Systems Ltd., #12, 6115-4th St., S.E., Calgary, Alberta, T2H
     2H9.
7.9  Bibliography

     Alter, A.J., "Sewerage and Sewage Disposal in Cold Regions", U.S.
     Army Cold Regions Research and Engineering Laboratory M3-C56,
     October 1969. 106 p., AD-698452.

     Environment Canada.  Environmental Protection Service, Proceedings
     of Symposium on Utilities Delivery in Arctic Regions, Report No.
     EPS 3-WP-77-1, Environmental Protection Serivce, Environment Canada,
     1977.

     Gamble, D.J. and Janssen, C.T.L., "Estimating the Cost of Garbage
     Collection for Settlements in Northern Regions", Northern Engineer,
     Winter 1974-75.

     Gamble, D.J., "Wabasca-Desmarais Water and Sanitation Feasibility
     Study", prepared for the Northern Development Group, Alberta
     Executive Council, 1974.

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                              SECTION 8
                               UTILIDORS
                                 Index
8        UTILIDORS                                                  8-1
8.1      Introduction                                               8-1
8.2      Design Considerations                                      8-4
8.2.1    Utilidors with central heating lines                       8-5
8.2.2    Utilidors with pipe heat tracing                           8-7
8.2.3    Above-ground Utilidors                                     8-7
8.2.4    Below-ground Utilidors                                     8-9
8.3      Components and Materials                                   8-11
8.3.1    Foundation                                                 8-11
8.3.2    Frame                                                      8-12
8.3.3    Exterior casing                                            8-13
8.3.4    Insulation                                                 8-13
8.3.5    Piping                                                     8-14
8.3.6    Cross-section design                                       8-14
8.3.7    Prefabricated Utilidors                                    8-15
8.4      Appurtenances                                              8-15
8.4.1    Above-ground hydrants                                      8-15
8.4.2    Sewer Access                                               8-16
8.4.3    Vaults                                                     8-17
8.4.4    Utilidor crossings                                         8-17
8.5      Thermal Considerations                                     8-18
8.6      Maintenance                                                8-20
8.7      Costs                                                      8-20
8.8      References                                                 8-21

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                             List of Figures
Figure                                                              Page
8-1      Various Utilidors Installed in Cold Regions                8-2
8-2      Temperature Variation in a Utilidor with Central  Hot
         Water Distribution, Fairbanks, Alaska                      8-7
8-3      Road Crossings for a Utilidor with Central Heating
         Lines, Inuvik, NWT                                         8-8
8-4      Buried Utilidor under Construction, Nome, Alaska           8-10
8-5      Above-ground Utilidor Hydrant                              8-16
8-6      Sewer Cleanouts                                            8-17

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                                  8-1
 8          UTILIDORS
 8.1        Introduction
           Utilidors are  conduits  that  enclose  utility piping which,
 in addition  to  water and sewer  pipes,  may include central heating, fuel
 oil, natural  gas,  electrical  and  telephone conduits.   Utilidors may be
 located  above,  below,  or at ground  level  and have been used  in stable
 and unstable  seasonal  frost and permafrost soils  as well  as  in snow [1].
 They may be  large  enough to provide access for maintenance purposes or
 for use  as a  walkway,  or they may be compact with no  air  spaces.  Single
 pipes or separate  pipes  on a  common pile  are not  Utilidors.   The size,
 shape, and materials used depend  upon  the  number  and  types of pipes,
 local conditions and requirements,  and economics.
           Utilidors have been constructed  in many northern locations  [1].
 Perhaps  the best-known examples of  above-ground Utilidors are in Inuvik,
 NWT [2,11,12].  Utilidors have also been  extensively  used below-ground
 in high  density areas  and in  permafrost areas  in  Russia [8,13].
 Examples of various  Utilidors that  have been constructed  in  cold regions
are illustrated in  Figure 8-1.
           Utilidors  are  not water distribution or  sewage  collection
 systems  in themselves.   They  are  commonly  used  in  cold  regions to
consolidate piping,  and  perhaps other  utilities,  particularly where
central  heating pipes are used and  for above-ground systems.   Also of
significance  are physical protection of pipes  and  insulation,  and
thermal  considerations.   As  with other cold regions  piping,  they  must
be insulated  to reduce heat loss but often  the  insulation is  located  on
the utilidor  exterior casing  rather  than on the individual pipes.   Other
freeze-protection measures, such as  recirculation  to  maintain  a  flow  in
water pipes, may also be necessary.  Most  utilidors have  some  mutually
beneficial heat transfer between the enclosed  pipes.   If  central heating
pipes are included,  heat loss from  these can be sufficient to  replace
utilidor heat losses and prevent freezing, but with this  arrangement
temperature control  within the utilidor is difficult.  This can  lead  to
inefficiency and undesirably  high temperatures in water pipes.   Freeze-
protection alone is  not  sufficient  justification for  the  use of

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                                                  3-2
             ^.
                                        oof panel
                               75 mm Fiberglass insulation
                   	Insulated high temperature water
                       supply and return, 200 0 to 32 0
                       Removable panel 0 759 mm
                       (22 Gauge) aluminum sheeting


                     - - Steel support frame
                       1500 or 2000
                       Asbestos cement watermain
                       200 0 Asbestos cement sewermain
                       U Bolt

                         Drift pin
                         Timber pile cap

                          2500 Timber pile
                          45m into permafrost
    Flexible sealant at overlap points
    150 0 Asbestos cement watermain
       19 mm Galvanized banding at pipe saddles
         Fiberglass or polyurethane insulation
             1 897 mm (14 Gauge)
             Corrugated metal pipe

             Flexible sealant
             2000 or 150 0
             Asbestos cement  sewermain
             Wood pipe saddle
                                                                                                 2000 Timber pile
                                                                        (c)  CMP Utilidor, Inuvik, N WT [2]
 (a) Utilidor with central heating lines, Inuvik, N WT [2]
610
;Wood frame
150 0 Asbestos cement sewermain
Wood tie down clamp
                   38 mm Polystyrene insulation
                  " boards sides and top (glued)
                   2000 or 1500
                   Asbestos cement watermain
                   Loose polystyrene insulation
            -4 jl20 mm Plywood
                   25 0 Drain hole with screen
                   Wood  pipe support
                   150 x  150 mm Fir pile cap
                   75x200 mm  Fir beam
                   Drift pin
             200 0 Timber pile at 4 6 m spacing
                                                                             -1  519 mm (16 Gauge) Steel
                                                                                       , 2 657 mm (12 Gauge) Steel top

                                                                            T \J   ]          \, 100 mm Polyurethane
                                                                          300 mm
                                                                                                     65 0 PVS Vacuum sewer
                                                                                                     25 0 Copper heat trace pipe
                                                                                              -"750'PVC Water
                                                                                       - Wood beam and supports as required
                                                                         (d)  Utilidor with vacuum sewer, Noorvik, Alaska [3]
 (b) Plywood box utilidor, Inuvik, N.W.T. [2]
                                                                          T
                                                                          430
                                                                                     430-
100 mm Polyurethane
            100 0 Sewer force  main
            13 mm  Plywood

            25 0 Copper  heat  trace
                                                                         (e)  Single pipe with heat tracing, Noorvik, Alaska
           FIGURE  8-1.    VARIOUS  UTILIDORS  INSTALLED  IN  COLD REGIONS

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                                                                      8-3
                Polyurethane insulation
                1500 Carrier pipe
                38 0 Potable water
                38 0 Gray water
                38 0 Pipe heat trace-supply
                38 0 Pipe heat trace-return
                38 0 Treated effluent
     300 0 Corrugated metal pipe casing
 (f)  Utilidor with many small pipes,
     Wamwnght, Alaska [4]
                                                                                                Sand pad
                                                                                                Clay trough
                                                                                                Non-heaving soil
                                                        (i)   Buried accessible utilidor, Mirryl, U.S.S.R  [8]
                 300 mm Corrugated metal pipe
                 Polyurethane insulation
                 Electric heating cable
                 18 mm Copper service lines
                40 mm Plastic isolation pipe
                100 mm Carrier pipe
                                                       Active layer
                                                       1 2 to 1 5 m
                                        Ice-rich
                                       permafrost
                                       300mm
                                       Granular base
                                       (minimum)
Granular backfill
Filter fabric

[ Vanes'(6 6 to 1 2 m)
';_L
 50 mm Extruded polystyrene board insulation (1 2 m x 1 8 m)
 Adjustable chain pipe hanger
 200 0 Wood stave sewer pipe
 1 7 m Corrugated aluminum plate, 2 54 mm wall
 1000, 150 0 or 200 0 Steel, cement lined circulated watermain
 when depth of cover less than 09m

 Extruded polystyrene board insulation  (1 2m X 1.8m)
(g) Service connection [5]
                                       (j)   Buried accessible utilidor, Nome, Alaska [9]
445
      178
Fiberglass-reinforced
plastic filament wound pipes
        Insulation surface treated
       ~ with mastic or paint
             - Electric heating cable (optional)
                 500 to 2500
               " Polyurethane foam insulation
                 Fiberglass-reinforced
               "plastic exterior casing
           - Water recirculation pipe (optional)
       - Galvanized bolt
         Aluminum or galvanized
         steel channel
(h) Prefabricated utilidor [6,7]
                                                                                                                                       34m
                                                                                                                                       1 5m
                                                                       (k)  Walkway utilidor, Cape Lisburne, Alaska [1]
                                                     FIGURE  8-1.    (CONTINUED)

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                                 8-4
utilidors since individually insulated pipes could be used.  Utilidors,
or utility tunnels designed for public passage are very expensive, and
are generally not justified for piping alone.  However, where they are
required for passage or transportation, there can be overall economic
benefits by locating utility conduits within them.
          In North America, utilidors are most commonly constructed
above-ground in permafrost areas.  Although below-ground utilities are
preferred, above-ground construction may be necessary where there is
ice-rich permafrost, expensive excavation, or a lack of equipment for the
installation and maintenance of underground utilities.  Temporary pipes
or piping that requires access may also be located above-ground.
          Utilidors have disadvantages.  Their applicability for a
particular location should be carefully assessed before implementation.
Individually insulated pipes, in a common trench or supported by a
common pile (see Figure 6-18) may be a more appropriate and economical
alternative [10].
8.2       Design Considerations
          Inclusion of conduits such as electrical power, natural gas,
and telephone cables, along with water and sewer lines in utilidors can
be cost-effective and aesthetic.  This practice is generally recommended
wherever practical.  The addition of central heating lines may require
significant changes in utilidor design and operation.  The use of central
heat generation and distribution is a more complex economic decision.
Walkways are sometimes constructed between buildings in construction
camps or military facilities or in high traffic and severe snow drifting
conditions.  In these situations placing utility lines within them should
be considered.  In some cases surface utilidors have been designed for
use as sidewalks.
         These common functions of utilidors are often the primary
benefit and reason for their use.  Some of the problems encountered when
other utilities besides water and sewer pipes are included in the
utilidor are:
          a)  jurisdiction problems in installation and maintenance;

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                                 8-5
          b)  coordination between various utility agencies during
              planning and construction;
          c)  differences in routing or other conflicting design criteria
              for various utilities or utilidor uses;
          d)  difficulty or restrictions in expansion or changes to
              utilities;
          e)  piping and utilidor design problems, particularly at
              intersections and bends;
          f)  compatibility of materials; and
          g)  larger size, and perhaps special materials, which increase
              the costs of utilidor construction and above-ground road
              crossings.
In some situations, such as at industrial camps, military bases or in
planned communities, these problems may be overcome with overall cost
savings and aesthetic benefits.
8.2.1     Utilidors with central heating lines
          The decision to use utilidors to carry central heating lines is
secondary to the benefits of central heating.  These benefits include
the elimination of less efficient individual building furnaces and a
significant cause of fires, central fuel storage, and the possible use
of waste heat (see Section 14).  These pipes often require access,
particularly for steam and condensate return lines.  If they are buried,
utilidors are necessary for access.  Separate pipes can be used for
above-ground systems and may be more economical, but consolidating piping
within a utilidor may be more aesthetic.
          When only central heating lines are considered, utilidors or
individually insulated pipes can be used (see Figures 14-8, 14-9 and
14-11).  When central heating and water and sewer lines are installed in
a utilidor, the former can give off enough heat to prevent freezing
temperatures within the utilidor.  This may eliminate or reduce the need
to loop and recirculate the water mains, although circulation is always
desirable in cold regions.  Because the utilidor exterior is insulated,
conventional, uninsulated water and sewer piping and appurtenances are
usually used.  For economical operation the central heating lines are

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                                 8-6
usually insulated.  In some cases it may be necessary  to  remove  some
insulation from around the heating pipes to provide enough heat  during
the coldest ambient temperatures.  The utilidor in Figure 8-1(a)
commonly has 0.25 m of insulation removed every 10 m.
          Problems occur because the heat source  is constant  and must
operate for all or most of the year.  Therefore,  when  the ambient
temperature is warmer, the interior  temperature of the utilidor  will
increase and undesirably high water  temperatures  can occur when  there  is
little or no flow in  the water pipes (see example 15-5).  Users  have
found it necessary to bleed considerable volumes  of water to  obtain cool
water [11].  For this reason it is desirable  to insulate  the  water  pipes
[10].
          The heating of a large air space  in the utilidor is less
efficient than the direct heating of water  and  its recirculation to
prevent freezing.  This inefficiency is more  significant  for
above-ground and large utilidors.  In some  situations  it  will be more
efficient to design and operate the  heating and the water and sewer
systems independently.  If a utilidor is used the benefits will  be
aesthetic for above-ground utilities, accessibility for below-ground
utilities, and structural support for the pipes.
          Thermal stratification can cause  freezing of lower  pipes  in
large open utilidors  when the average temperature is adequate.  Vertical
air  flow barriers may be necessary to prevent air currents along
inclined utilidors [11].  Thermal shielding of pipes and  poor
temperature distribution within a utilidor  are shown  in Figure 8-2  [14].
          Utilidors for central heat distribution pipes and  other
utilities are expensive.  Their large size  increases  the  material  and
construction costs, particularly for above-ground systems and
road-crossings.   Central heating is  only economical  in relatively high
density developments, not  single-family housing areas. With adequate
planning  these utilidors can  form the backbone of large community
systems, with non-heated utilidors  servicing  adjacent  lower  density areas,
           Central heating  systems must  provide continuity of service and
they should  be looped so  that areas  can be  isolated  for maintenance or

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                                  8-7
             	610-
                 50 mm Rigid insulation
              0.813 mm Aluminum cover
                      20 mm Plywood
  350
        50 x 250 mm Wood beam
        20 mm Hot water return
        20 mm Hot water supply
        Approximate isotherm
20 mm Cold water
   Thermocouples
 Ambient air temperature: -29C
 Hot water input temperature: 69C
150 mm Steel channel
                                    100 mm Pipe pile
     FIGURE 8-2.   TEMPERATURE VARIATION IN A UTILIDOR WITH CENTRAL
                   HOT WATER DISTRIBUTION,  FAIRBANKS, ALASKA  [14]
repairs,  long-range planning is  necessary to incorporate future
expansion and to allow  efficient  staging without the need for temporary
or unused lines to complete loops.
8.2.2     Utilidors with  pipe heat  tracing
          Utilidors with  the pipe heat tracing are designed  specifically
to supply the amount of heat necessary to  prevent freezing of the pipes
in the utilidor.   Low temperature,  80C to 98C, glycol solutions or
other non-freezing fluids,  and small-diameter bare pipes are commonly used
(see Section 15.4.3).   They can be  used to heat Utilidors or thaw out
frozen pipes.  Many of  the  inefficiencies  and problems with central
heating lines do not apply.
8.2.3     Above-ground  utilidors
          Below-ground  utilities  are usually preferred, but local
conditions, operating requirements  and economics can make above-ground
utilities and utilidors attractive.   Factors to be considered when
choosing between above  or below-ground utilities are detailed in

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                                  8-8
Section  2.   It  should  be  noted  that  above-ground  utilities were often
necessary in  the  past  because  the  types  of  insulations in common use
required dry  conditions and  accessibility.   For the  same reason, buried
accessible  utilidors were used.   The development  and availability of
near-hydrophobic  rigid plastic  foam  insulations,  such as polyurethane and
extruded polystyrene,  has made  buried systems  feasible and more
attractive  in many situations.
         Above-ground  utilidors  should be as compact and as close to the
ground as practical to reduce  the  obstruction to  traffic.  Low utilidors
also  reduce the elevation of buildings necessary  for gravity sewer
drainage.   Utilidors with central  heating lines are  often large and
require  expensive wood or corrugated metal  arch structures at road
crossings (Figure 8-3).   Vacuum or pressure sewer systems may be
attractive  in undulating  areas  since the utilidor can follow the ground
surface  or  can  be buried  at  a  constant depth.   These systems use smaller-
diameter pipes  than gravity  systems.  When  small-diameter water and
sewer pipes are used,  the utilidor size  can be reduced (see Figure 7-8).
(a)  Wood
(b)  Corrugated Metal Arch
 FIGURE 8-3.  ROAD CROSSINGS FOR A UTILIDOR WITH CENTRAL HEATING LINES
              INUVIK, NWT

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                                  8-9
          Above-ground  util^'dors  are  located  within rights-of-way behind
building  lots  where  both  physical and  legal access  are provided.
Buildings should  be  located  near  the  utilidor to  reduce the length of
service lines.  A minimum of 3  m  between  building and  utilidor is often
specified for  fire protection.  The street layout must consider the
looping of water  mains  for recirculation, the expense  of road-crossings
and vaults, and the  high  cost per metre,  which are  characteristics of
above-ground utilidors.   An  example of  good planning is illustrated in
Figure 2-14.
          Utilidors  have  been routed  through  the  crawl space in buildings
to provide thermal and  physical protection for the  pipes, eliminate the
service connection utilidettes  which  are  the  most freeze-susceptible
portion of cold regions utility systems,  and  reduce the length of
utilidor and right-of-way required.   Problems with  this layout can
include the provision for access  to piping and the  danger of fires which
could jeopardize  the community  utility  system. Fire and smoke can
travel along utilidors  to other buildings.  Fire  resistant materials and
fire cutoff walls have  been  used  to minimize  this danger.
          People  often  walk  on  utilidors, but because  the travelled
surface and utilidor will require increased maintenance this is often
discouraged by design and legislation.  In some locations, they have
been designed as  sidewalks,  but this  is often impractical because of the
routing requirements for  the utilidors  and their  elevation.
8.2.4     Below-ground  utilidors
          Although buried utilidors,  usually  of concrete, have been
constructed in unstable soils in  many large communities in northern
Russia, they have had limited application in  the  cold  regions of North
America and in Antarctica [1].  Few buried utilidors have been con-
structed without  the inclusion of central heating lines and perhaps other
conduits besides  water  and sewer  pipes.  A notable  exception to all of
these generalities is the  corrugated metal pipe utilidor for water and,
sewer lines in Nome Alaska (Figures 8-1(j) and 8-4).   The primary
advantages of buried utilidors are access for maintenance and repairs,
the consolidation of utilities in  a single structure and  trench,  and thermal

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                                8-10
            FIGURE 8-4.  BURIED UTILIDOR UNDER CONSTRUCTION,
                         NOME, ALASKA
considerations which may include freeze-protection and ventilation  to
reduce the thawing of permafrost.  In some cases, individual  pipes  or
utilidors without an air space (for example Figures 8-1(h) and  14-11)
may be appropriate and more economical.
          Below-ground utilidors are subject  to ground movements  from
frost-heaving or thaw-settlement and groundwater  infiltration,  and  this
has caused failures in ice-rich permafrost.   To prevent  progressive
thawing of permafrost, open utilidors with natural ventilation  have been
used in Russia.  Vents are opened during the  winter  to maintain
sub-freezing  temperatures within the utilidor and refreeze  the
foundation soils that  were thawed the previous  summer.   Other foundation
designs that  can be used  in permafrost  areas  include  the provision of
supports, refrigeration,  insulation, and  improving  the  foundation soils
within  the expected thaw  zone (see  Section  15.6.1).   Groundwater, melt-
water and water  from  pipe breaks must be considered  in  both unstable and
stable  soils.  In  the  spring, flooding  can  occur  in  buried  utilidors

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                                 8-11
which have an air space.  Provisions to allow drainage of  the  utilidor
must be made; watertight utilidors are desirable and usually required.
Diversions or cutoff walls in the trench may be necessary  in permafrost
areas to prevent detrimental groundwater flow along the  trench.
8.3       Components and Materials
          Utilidors that are well designed and constructed with high
quality materials have a longer useful life, cost less to  operate and
provide more reliable service.  Utilidors which have performed best were
constructed with metal exterior casing, used closed-cell insulation,
were structurally sound and had a solid foundation [2],  The basic
components of a utilidor are:
a)
b)
c)
d)
e)
foundation,
frame ,
exterior casing,
insulation, and
piping.
Foundation
8.3.1
          Foundation considerations and design will be different  for
utilidors that are below-ground, at ground level or elevated.  Each
requires site investigations and designs that will accommodate, reduce
or eliminate the effects of frost-heaving, settlement and  surface and
subsurface drainage.
          Above-ground utilidors must be supported to provide grades for
gravity sewers and to allow the draining of pipes and the  utilidor.  Pipes
must be adequately anchored to resist hydraulic and thermal expansion stresses.
          Where ground movements are within acceptable limits, utilidors
can be installed directly on the ground, or on a berm, earth mounds,
sleepers or posts.
          In unstable areas utilidors are commonly supported on piles
which are adequately embedded into the permafrost (see Section 15.6.3).
The piles are dry augered if possible because thawing the  permafrost
with steam or hot water increases the freeze-back period and
frost-heaving.  Because of the light vreight of utilidors,  the vertical
loads on the piles are relatively small and frost-heaving  will usually

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                                 8-12
be the most significant design consideration for embedding  piles.
Lateral forces may be significant on some permafrost  slopes, and lateral
thermal expansion and hydraulic stresses must be considered at bends.
Various types of piles have been used to support above-ground piping.
The selection depends upon the availability of local  materials,  the
length of pile required and economics.  Piles used  in Inuvik, NWT, are
usually rough timber poles and are embedded 4 to 6  m.   At Norman Wells,
NWT, frost-heaving is severe and 100-mm diameter steel  pipe is driven  12
m and grouted to the fractured shale bedrock.  Piles  may cost from $200
to over $750 each and may account for 10 to 20% of  the  total cost of
above-ground utilidors.  Small utilidors are usually  placed on a  single
pile, but large utilidors may require double piling for stability.   The
utilidor structure must be adequately anchored to  the pile  foundation.
Pile caps are often used to allow for poor alignment.
          Buried utilidors in stable soils have conventional design
considerations which include surface loads.  Frost-heave must be
considered  for shallow-buried utilidors,  and in ice-rich  permafrost
soils, thawing must be  prevented or considered in  the design  (see
Section 15.6.1).
8.3.2     Frame
          The supporting frame must keep the above-ground  utilidors  rigid
in  spanning piles or other supporting structures.   The utilidor  dead
loads, live loads including people, and  stability  must be  considered  in
the  structural design.   In some  instances  steel  has been used,  but
wooden beams are more common.   Solid utilidors may utilize  the  pipe,
insulation  and  shell for beam strength  (Figure 8-1(g,h)).   An  economic
analysis would  indicate the best  spacing  of  piles  versus increasing  the
beam  strength of  the utilidor frame.  Utilidors  supported  by wooden
beams  in  Inuvik,  NWT, usually span  4.5  m.   Steel  beams or  pipe  can be
used  to span up  to  7.5  m,  which is  generally the  practical limit without
special designs.
           Buried  utilidors must  also  have  some  beam strength to hold pipe
grades and  span  local  poor bedding  or  foundation soils.  Beam strength
is  usually  incorporated into  the exterior  casing.

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                                  8-13
8.3.3     Exterior Casing
          The primary function of the exterior casing  is  usually to  hold
the insulation in place and to protect the pipes  from  the weather and
physical damage.  When the exterior casing is an  integral part  of the
structural strength and rigidity it is usually metal or fibreglass with
polyurethane insulation bonded to it.
          The outer shell of above-ground utilidors should be designed
for easy removal to provide access to piping.  This is particularly
important at appurtenances, but is desirable along the complete utilidor.
The joints in the sections must be designed to seal against  rain, snow
or air infiltration.  Drain holes located in the  bottom should  be prov-
ided periodically to allow drainage in case of a  pipe  break.
         Materials that have been used for the exterior casing  include
corrugated and sheet metal, plywood or wooden beams, and  fiberglass
reinforced plastic.  Concrete has also been used  for surface or buried
utilidors.  Although wooden box utilidors have the lowest capital cost,
they have a low life expectancy and the highest maintenance  costs due to
painting requirements and physical damage.  Wood  is easy  to  work with
and the utilidor, vaults and service connections  can be easily  constr-
ucted on-site even in cold weather.  Wooden utilidors  are sometimes
covered with a thin metal sheet or asphalt paper.  Metal  utilidors may
be difficult to fabricate and install, particularly at bends, junctions
and appurtenances.  They are rugged and have a longer  life expectancy,
and require less maintenance than wooden exterior casing  utilidors.
         Below-ground utilidors require a rigid exterior  casing that
is watertight and provides the structural strength required  by  the
utilidor.
8.3.4    Insulation
          Insulation is probably the most critical component in all  cold
regions piping systems, including utilidors.  Water can enter the
utilidor at joints or from breaks in the pipes, and it is impractical to
keep the insulation dry.  Insulations that absorb moisture lose their
insulating value, particularly when the moisture  freezes; therefore,

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                                 8-14
asbestos fibre, rock wool, glass fibre, wood, sawdust, peat moss  and
similar materials are undesirable and must not be  used in  inaccessible
utilidors.  Polyurethane, and expanded and extruded  polystyrene  are  the
most common insulations used.  Ground or bead polystyrene  and  foamed-in-
place polyurethane can be used to fill the voids in  utilidors.   The
former provides access to pipes for repair and removal.  Fire  resistant
insulations are preferred since they reduce  the  spread of  fire  along
utilidors.
          Thermal characteristics of various insulations are given in
Appendix C and  Section 15.7.2.
8.3.5     Piping
          Leaks from pipes and joints in utilidors may cause water and
icing damage  to the utilidor, and there  is also  a  danger of  contamina-
tion and cross-connections.  Most public health  codes do not allow the
proximity of  water and sewer pipes.  Wavers  or adoption of new codes
will be necessary before  utilidors can be used.   In  the Northwest
Territories,  water and sewer pipes are allowed in  a  common trench or
utilidor if pressure-rated pipes and  joints  are  used and  all  pipes are
tested  for  zero leakage.  Open sewers are not allowed  and  sewer
cleanouts must  be capped.
          Most  types of  pipe materials have  been used  in  utilidors.   Each
has advantages  and disadvantages.  Rigid  pipes with  welded or  equivalent
joints  may  not  require as much support or hydraulic  thrust blocking at
bends,  hydrants and  intersections, but the  design must  allow for thermal
expansion.
8.3.6     Cross-section  design
          The cross-section  design and  piping  arrangement will depend
upon  the access required and  type, size  and  number of pipes to be
included  in the utilidor.  Other  considerations  may include standard
sizes  of materials,  for  example  4  feet x 8  feet  plywood sheets, and  the
routing of  piping.   The  utilidor  size is often  dictated by the maximum
dimensions  of pipe  appurtenances,  repair clamps  and  joints, and the
spacing of  pipes  that  is necessary at deflections and intersections.

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                                  8-15
Pipes with smooth  joints may be  placed closer  together  and  a smaller
cross-section may  be used.  Installation, repairs and maintenance
requirements must  also be considered.
8.3.7     Prefabricated utilidors
          Most utilidors are prefabricated  to  some  extent,  but  all
require some field construction.  The primary  advantage  of
prefabrication is  the reduction  in  field-erection time.   This reduces
labour costs and facilitates installation within the  short  construction
season, but prefabricated utilidors generally  have  high  material costs.
High quality control and special designs are possible in shop
fabrication.  Prefabricated utilidors commonly combine  the  functions of
the basic utilidor components.   The pipes,  rigid insulation and exterior
casing provide beam strength, rigidity, and thermal and  physical
protection.
          One type of prefabricated utilidor consists of a  carrier  pipe,
polyurethane foam  insulation, and a bonded  exterior casing  of sheet or
corrugated metal, glass fiber reinforced plastic or plastic, depending
on the strength requirements (see Figures 8-l(f)(g),  A-l  and A-2).  This
system is commonly used for small-diameter  pipes and  service connections
to buildings.  A completely prefabricated glass fibre reinforced plastic
two-pipe utilidor  system is illustrated in  Figure 8-1(h).   It is
longitudinally segmented and has staggered  joints to  allow  removal  of
individual pipes.
          Appurtenances such as  hydrants, cleanouts, and  bends  are
prefabricated modules that are inserted into the system  where required
[16].
8.4       Appurtenances
          Some appurtenances for piping systems and utilidors must be
specially designed or adapted.   This applies particularly for above-ground
utilidors, where special hydrants, valves, cleanouts and  bends may be
necessary.
8.4.1     Above-ground hydrants
          "In-line" hydrants located directly on a tee in the water main
are recommended.  They may be installed without additional  freeze prot-

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                                  8-16
action if the barrel is  short  enough  that  heat from the water main will
prevent the valve from freezing.   Leakage  through the valve must be
prevented since the freezing of water may  damage the hydrant and make
thawing necessary before use.   Building-type  fire hydrant outlets and
butterfly valves have been  used because  of their small size and light
weight.  One design is illustrated in Figure  8-5.
            Flanged tee
Hydrant housing filled
with loose batt insulation
        Utilidor
                  -Butterfly valve with 50x50mm
                             square operating nut
     Watermain
                                        2-Way Siamese connection
                                        Removable  end cover
                                       Steel stub flange
                FIGURE 8-5.   ABOVE-GROUND UTILIDOR HYDRANT
           The  hydrant enclosure must be rugged, well insulated, and
appropriately  marked and painted.  Access to the hydrants must be  quick
and  easy  but it must also discourage vandalism.
 8.4.2
Sewer access
           For above-ground sewers, and water and sewer pipes within  a
utilidor,  the sewer access cleanouts must be sealed to prevent
cross-contamination.  The flanged tees for pipes larger  than 200 mm
diameter  usually provide an adequate opening to insert cleaning or
thawing  equipment.  Standard fittings for smaller pipes  do  not  provide
adequate  access in both directions.  Special fittings with  larger  slot
openings  that can be sealed have been used (Figure 8-6).  Special  venting
may be necessary when the building vents are not adequate.

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                                  8-17
     Galvanized bolt
            Lid
            Flange
              H-200mm-I
                                               750mm
                            . Rubber gasket
                                                                      Flange
   Brass nut
                                    Fiberglass reinforced plastic
           Cloth impregnated rubber gasket to
           indicate when  pipe is under pressure
                                          Steel
                       FIGURE 8-6.   SEWER CLEANOUTS
 J.4.3
Vaults
          Vaults are  the  above-ground enclosures which contain  the
hydrants, valves,  thrust  blocks,  intersections, bends, and other  piping
system appurtenances,  including  recirculation pumps, heaters and
controls.  Access  to  these  appurtenances is provided through the  vaults,
which can be only  slight  enlargements of the utilidor, or small
buildings.  Usually they  are   individually designed and fabricated.
Thrust blocking and vaults  at  bends may not be required where small-
diameter pipes or  rigid pipes  are used.  The vaults contain the
expensive piping system appurtenances which can be a significant  portion
of the total utilidor  cost.   Vaulted appurtenances accounted for  30%  of
the cost for the two-pipe wooden  box utilidor shown in Figure 8-l(b).
8.4.4     Utilidor crossings
          Pedestrian  and  vehicle  crossings must be provided where
above-ground utilidors are  used.   The cost of these crossings is  a
function of the utilidor  size  and its height above the ground.  Large  or
high utilidors require bridge-type structures for road overpasses
(Figure 8-3).  Costs  in  1977 were approximately $35 000 in Inuvik, NWT.

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                                 8-18
Smaller utilidors can be protected by less expensive corrugated metal
pipe culverts (see Figure 7-8).
          The utilidor and road layout should minimize  the number  of
crossings that are required.  The roadway and drainage  system must  take
into consideration the locations of utilidor overpasses.   Steep
approaches to the crossing can impair driver visibility.   Long
approaches can disrupt the surface drainage system, and  the  overpasses
tend to become drainage paths that accumulate garbage.
          Utilidors and piping can also be elevated above  roadways  or
buried at road crossings.  These alternatives may  require  expensive lift
stations which can impede the complete drainage of the  pipes and
utilidor.  Underpasses can be excavated, however,  this  is  difficult and
expensive in areas of ice-rich permafrost.  In  1974, the roadway
excavation, permafrost protection and utilidor  reinforcing for  an
underpass in Inuvik, NWT, cost $70 000.
          Pedestrian crossings can be a part of the roadway  crossings
but separate wooden stairways may also be required at certain  locations.
8.5       Thermal Considerations
          The placement of pipes within a utilidor provides  possible
thermal benefits in that  the  proximity of water mains to warm  sewer
pipes, and heating pipes  if  they are  included,  reduces  the risk of
freezing and partially compensates for heat loss.   It is important to
minimize the surface area of  the utilidor to  reduce heat loss.   The size
and shape of a  utilidor may,  however, be dictated  by considerations
other  than heat  loss.  Most  utilidors are no more  thermally efficient
than  individual  pipes  with annular insulation,  and utilidors containing
large  air spaces will  be  less efficient.  The  effects of utilidor shape
and size on  heat loss  are illustrated  in Figure 15-5.   Information
required to  estimate heat loss and freeze-up  time  for  pipes and
utilidors is presented  in Section  15.
          All  exposed  utilidor surfaces  should  be  insulated.  Thermal
breaks or penetrations  should be  isolated  from the pipes.    Insulated
flanges  and  extra  insulation at  pipe  anchors  have  been  used.  Additional

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                                  8-19
 insulation  should  be  provided  at  appurtenances  and  vaults with larger
 surface  areas  than the  utilidor.
          Freeze-protection provided  for  utilidor piping can be similar
 to  that  for single pipes,  and  heat  tracing  can  be used  to maintain a
 minimum  temperature.   Temperature control within the  utilidor is
 difficult when control  heating or domestic  hot  water  lines are included.
          While soil  cover and snow provide some natural insulation for
 buried utilidors,  shallow-buried, and  above-ground  piping and utilidors
 are  subject to extreme  air temperatures.  They  must be  designed for the
 lowest expected temperatures and  wind  conditions.  The  design must take
 into  account:
          a)   short freeze-up  time,
          b)   high maximum rate of  heat loss,
          c)   high annual  heat loss, and
          d)   expansion and contraction caused  by changes in air
               temperature  or because the  pipes  have been drained.
          The  most critical expansion  and contraction problems occur
 when  the system is started up,  or when maintenance  or emergencies
 require  that the system be shut down and  drained.
          Two  conditions requiring  calculations are the  maximum movement
 due  to temperature changes and  the maximum  stress if  movement is
 restrained.  With  metal pipe,  it  is generally impractical to restrain
 thermal movements.  Maximum movement can  be provided  by  the  use of
 compression or sleeve-type couplings,  expansion joints,  "snaking"  the
 pipe, or providing  expansion loops.  Most in-line expansion  joints do
 not  perform adequately  under freezing  conditions; however, a
 free-flexing bellows  joint will operate even with residual water frozen
 inside [16].
 8.6       Maintenance
          Repairs  or  replacement  of piping  and  subsequent reclosure of
 the utilidor must  be  considered in the cross-section  design  and
materials selection.  Extra materials  and components  used within the
 system must be  available on-site.  Standardization  of components,
materials and  design greatly facilitates  maintenance.

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                                 8-20
          Below-ground utilidors should be the walkway-type  for easy
access.  Alternatively, no air space should be provided in shallow-
buried utilidors where the only access is by excavation.  Above-ground
utilidors need not have walkways.  Access to pipes and appurtenances  is
facilitated by removable panels.
          Vandalism, accidents, and weathering of exposed utilidors will
result in extra maintenance and must be considered in the materials
selection and design.
          Repairs and service connections must be carried out  only by
authorized personnel.  The service conduit design, particularly the
connection to the utilidor, may be specified to ensure engineering and
aesthetic compatibility.
8.7       Costs
          Capital costs, maintenance and heating requirements, and
service life are important factors in utilidor design and materials
selection [2,11].  Capital costs can be reduced by lowering  standards;
however, this may be offset by higher operating and  replacement costs.
Above-ground utilidors must be particularly rugged to contend  with the
rigorous climatic conditions and vandalism.  Numerous "low-cost"
utilidors have not survived their intended lifespan.
          The capital costs for utilidors depend on  the number, size,
and function of the enclosed pipes, the degree of prefabrication, the
foundation requirements and local conditions.  The cost breakdown for a
two-pipe, wooden box utilidor on piles in Inuvik, NWT (Figure  8-l(b))
was:
                                                            17%
          Engineering - design                     7%
                      - field supervision          10%
          Materials (including transportation)             33%
          Construction                                     50%
Material costs for the carrier pipe utilidor in Figure 8-1(f,g) are
presented in Table A-3.  The cost for the small utilidor  in Figure
8-l(d) was approximately $230/m in 1977.  The water and sewer wooden  box
utilidor on piles constructed in a subdivision of  Inuvik,  NWT,  in  1976,
cost $600/m for straight portions but average costs were  $670/m and

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                                 8-21
$805/m when the costs for vaults and road crossings were included.

Large utilidors with central heating lines are more expensive.  Costs

for the utilidor in Figure 8-l(a) were over $1200/m.

          Estimated annual maintenance costs in 1974 for utilidors in

Inuvik, NWT, ranged from $34 to $91 per service connection.

8.8       References

1.  Tobiasson, W., "Utility Tunnel Experience in Cold Regions",
      American Public Works Association, Special Report No.  41, pp.
      125-138, 1971.

2.  Gamble, D.J. and P. Lukomskyj, "Utilidors in the Canadian North",
      Canadian Journal of Civil Engineering, _2(2):162-168, 1975.

3.  Rogness, D.R. and W. Ryan, "Vacuum Sewage Collection in the Arctic,
      Noorvik, Alaska; A Case Study", IN:  Utilities Delivery in Arctic
      Regions, Environmental Protection Service, Ottawa, Ontario EPS
      3-WP-77-1, pp.  505-522, 1977.

4.  Reid, B., "Some Technical Aspects of the Alaska Village
      Demonstration Project", IN:  Utilities Delivery in Arctic Regions,
      Environmental Protection Service, Ottawa, Ontario, EPS 3-WP-77-1,
      pp.  391-438, 1977.

5.  Ryan, W., "Design Guidelines for Piping Systems", IN:  Utilities
      Delivery in Arctic Regions, Environmental Protection Service,
      Ottawa, Ontario, EPS 3-WP-77-1, 1977.

6.  Gamble, D.J., "Unlocking the Utilidor:  Northern Uilities Design and
      Cost Analysis," IN:  Utilities Delivery in Arctic Regions,
      Environmental Protection Service, Ottawa, Ontario, EPS 3-WP-77-1, 1977.

7.  Fiberlite Products Co. Ltd, "Engineering Guide to Prefabricated
      Utilidors", Edmonton, Alberta, n.d.

8.  Slipchenko, W., (ed) , "Handbook of Water Utilities, Sewers, and
      Heating Networks designed for Settlements in Permafrost Regions",
      Northern Science Research Group, Department of Indian Affairs and
      Northern Developement, Ottawa, Ontario, NSRG 70-1, 1970.

9.  Leman, L.D., Storbo, A.L., Crum, J.A., and Eddy, G.L., "Underground
      Utilidors in Nome, Alaska", Applied Techniques for Cold
      Environments, American Society of Civil Engineers, New York, New
      York, pp.  501-512, 1978.

10. Hoffman, C.R., "Above-ground Utilidor Piping System for Cold-Weather
      Regions", Naval Civil Engineering laboratory, Port Hueneme,
      California, Technical Report R734, 1971.

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                                 8-22
11.  Leitch, A.F. and G.W. Heinke,  "Comparison of Utilidors in Inuvik,
      NWT", Department of Civil Engineering, University of Toronto,
      Toronto, Ontario, 1970.

12.  Cooper, P.F. "Engineering Notes on Two Utilidors", Northern Science
      Research Group, Department of Indian Affairs and Northern
      Development, Ottawa, Ontario, 1968.

13.  Porkhaev, G.V., "Underground Utility Lines", National Research
      Council of Canada, Ottawa, Ontario, Technical Translation TT-1221,
      1965.

14.  Reed, S.C., "Field Performance of a Subarctic Utilidor", IN:
      Utilities Delivery in Arctic Regions, Environmental Protection
      Service, Ottawa, Ontario, EPS 3-WP-77-1, pp. 448-468, 1977.

15.  James, F., "Buried Pipe Systems in Canada's Arctic", The Northern
      Engineer, JJ(11):4-12, 1976.

16.  Gilpin, R.R. and M.G. Faulkner, "Expansion Joints for
      Low-Temperature Above-Ground Water Piping Systems", IN:  Utilities
      Delivery in Arctic Regions, Environmental Protection Service,
      Ottawa, Ontario, EPS 3-WP-77-1, pp. 346-363, 1977.

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                                SECTION 9
                            WASTEWATER TREATMENT
                                  Index
9        WASTEWATER TREATMENT                                       9-1
9.1      General Considerations                                     9-1
9.1.1    Treatment objectives                                       9-1
9.1.2    Period of design                                           9-1
9.1.3    Site selection                                             9-1
9.2      Wastewater Characteristics                                 9-2
9.2.1    Quantity                                                   9-2
9.2.2    Quality                                                    9-4
9.2.3    Flow variation                                             9-8
9.3      Unit Operations                                            9-9
9.3.1    Mixing                                                     9-9
9.3.2    Sedimentation                                              9-9
9.3.3    Filtration                                                 9-10
9.3.4    Gas transfer                                               9-10
9.3.5    Adsorption and chemical reactions                          9-12
9.4      Unit Processes                                             9-12
9.4.1    Preliminary treatment                                      9-13
9.4.2    Primary treatment                                          9-13
9.4.3    Biological processes                                       9-14
9.5      On-site Treatment                                          9-30
9.5.1    Systems with discharge                                     9-31
9.5.2    Low or no discharge systems                                9-31
9.6      Operation and Maintenance                                  9-33
9.6.1    Contents of O&M manuals                                    9-33
9.6.2    Design for O&M                                             9-34
9.7      Costs                                                      9-34
9.8      References                                                 9-37
9.9      Bibliography                                               9-38

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                             List of Figures
Figure
 9-1     Viscosity Effects vs Temperature
 9-2     Settling Detention Time vs Temperature
 9-3     Two-cell Facultative Lagoon Flow Control
 9-4     Stop-log Manhole and Lagoon Outlets
 9-5     Dimensions of Lagoons
 9-6     Power and Air Requirements for 3-m Deep Partial-Mix
         Aerated Lagoon
 9-7     Oxidation Ditch for Subarctic
Page
9-11
9-11
9-15
9-15
9-19

9-20
9-24
                               LIST OF TABLES
Table                                                               Page
 9-1     Typical Per Person Sewage Flow                             9-3
 9-2     Institutional Sanitary Facilities in Cold Climates         9-4
 9-3     Domestic Sewage Sourees                                    9-5
 9-4     Estimated Sourees of Sewage Pollutants                     9-6
 9-5     Raw Sewage Temperatures at Treatment Facility              9-8
 9-6     Variation in Solubility of Typieal Chemicals with
         Temperature                                                9-12
 9-7     Characteristics of Typical Aeration Equipment              9-20
 9-8     Temperature Coefficients for Biological Treatment          9-22
 9-9     Cost Comparison - Construction Camp Wastewater Treatment
         Systems                                                    9-26
 9-10    Typieal Coliform Contents in Cold Regions Wastewaters      9-28
 9-11    Typical Sludge Production Rates                            9-29
 9-12    Construction Costs - Partial-mix Aerated Lagoons           9-35
 9-13    Relative Cost Factors - Partial-mix Aerated Lagoons        9-36
 9-14    Construction Costs - Eielson AFB Aerated Lagoon            9-36
 9-15    Estimated Annual Operation and Maintenance Costs -
         Partial-mix Aerated Lagoons in Alaska                      9-37

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                                    9-1
9        WASTEWATER  TREATMENT
9.1      General Considerations
         This section is not a complete design  text  for  wastewater
treatment systems.   It gives special emphasis to  those factors  which are
unique to the cold regions.  Reference is made  to other  manuals and
texts for basic sanitary engineering criteria and procedures.   The
special factors for  cold regions are not just responses  to  low
temperatures but also include:  remote locations, logistical  problems
during construction  and operational resupply, permafrost and  other
unstable site conditions, lack of skilled manpower, very high energy
costs, rapid turnover of operator personnel, and  in  some cases  unique
environmental aspects.
9.1.1    Treatment objectives
         Basic treatment objectives are not unique to the cold  regions.
The fundamental purpose of wastewater treatment in all locations  is
protection of human  health.  The next priority is to protect  the
receiving environment.  The guidelines, criteria  and standards  set by  the
applicable regulatory agencies must be considered prior  to  undertaking
any design.  Section 10 of this manual discusses  impacts on the receiving
environment.
9.1.2    Period of design
         The design  life (Section 2.6.2) for waste treatment  systems is a
function of the community or facility served.   It can also  be specified
by the regulatory and/or funding agencies.  It is essential to  determine
design life in the initial planning stages since  this factor  determines
the service life and treatment capacity requirements based  on present and
future population.
9.1.3    Site selection
         Most of the basic site selection criteria (i.e., advantageous
topography, suitable discharge point, etc.) are applicable  to the cold
regions.  Of special concern is the presence of permafrost  under  the
intended site.  The  presence of permafrost will strongly influence the
type of system chosen, and the economics of design and construction to

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                                   9-2
ensure long-term stability of the system.  Another factor  requiring more
emphasis in cold regions is easy, continuous access to all critical
points in the system.  Access roads and pathways must not  be  located
where snow drifting or icing will occur.  The layout of  the treatment
system itself must avoid creation of excessive snow drifts.   If  convenient
access cannot be provided, and easily maintained, then winter time
maintenance will probably not be performed.  Distance requirements  to
avoid nuisance conditions are generally applicable in both temperate and
cold regions.  Lagoons should be no closer than 0.4 km (0.25  mi)  from  any
residence.  All treatment systems may experience odour problems  due  to
operational difficulties, so any locations in close proximity to
habitations should be avoided.
9.2      Wastewater Characteristics
         Wastewater characteristics in cold  regions can  be different  from
those in temperate regions, both with respect to quantity  and quality.
In general, the total quantity tends to be close to the  amount of potable
water used by the community.  Storm water  is often excluded  from the
collection systems.   Infiltration is also  not usually a  factor in the
Arctic since collection  systems are usually  insulated and  tightly sealed
to ensure thermal integrity.  Communities  such as Anchorage,  Ak, and
others in the subarctic  experience water wasting and  infiltration,  but
design considerations are not different  from eonventional  practice  with
high  flows and  low organic  loadings.  The  wastewater  at  most  other  cold
regions installations tends  to be lower  in volume and higher  in strength
than  at comparable facilities elsewhere.   The wastewater from most  cold
regions facilities is essentially domestic in character, with the
possible addition of  laundry wastes and  extra amounts of garbage from
institutional type kitchens.
9.2.1    Quantity
         The  requirements  for total quantity of  water  needed  are
discussed  in  Section  3  of  this manual.   The  resulting  per person sewage
flows  depend  on the  type of installation and its permananee.   Table 9-1
summarizes  typical  sewage  flows  for  a  variety  of oold regions situations.

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                                    9-3
         TABLE 9-1.  TYPICAL PER PERSON SEWAGE FLOW (L/person/d*)



 1.   Permanent Military Bases and Civilian Communities

     a)   > 1000 population with conventional piped water and sewage:

         Thule Air Force Base,  Greenland        303
         College,  Ak                            265
         Fairbanks, Ak                          303
         Ski  resorts in Colorado and Montana    345
             Average                            300 L/person/d

     b)   < 1000 with conventional piped water and  sewage:

         Bethel, Ak                             265
         DEW  Line,  Greenland                    208
             Average                            240 L/person/d

     c)   with truck haul systems,  conventional  internal  plumbing:

             Average                            140 L/person/d

     d)   with truck haul systems,  low flush  toilets:

             Average                            90 L/person/d

     e)   no household  plumbing,  water tanks  and  honeybucket  toilet:

             Average                            1.5 L/person/d

     f)   same as (e) above  but with  central  bathhouse  and  laundry:

             Average                             15 L/person/d

2.   Construction Camps

         North  Slope,  Ak (1971)                      189
         "Typical"  Canadian                          227
         Alaska Pipeline (1976)                      258
            Average                                 220  L/person/d

3.  Remote Military with Limited Availability of Water

        McMurdo, Antarctica                         151
         Barrow, Ak  (DBS  Sta)                        114
         "Typical" Army  Field Camp                   129
            Average                                 130  L/person/d

* 1 L/person/d = 0.264  gallons/capita/day US.

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                                   9-4
Separate facilities  such  as  schools, laundries,  restaurants  and  hotels
with conventional plumbing tend  to have  loadings similar  to  conventional
temperate zone practice.
         Whenever possible,  actual data  from  the specific site of
concern, or one  similar,  should  be used  to  establish a design value for
per person flow.  Where such data are  not available, the  average values
on Table 9-1  should  be used  for  the  appropriate  type facility.  These
values are all for permanent residential personnel.   If an accurate
population count is  not available, it  should  be  assumed for design
purposes that there  are 3.6  people per residence for military stations,
and 4.5 people for remote civilian communities.   For day  workers whose
residences are not serviced  by the treatment  system  an allowance of 57
L/person per  eight-hour shift should be  made.  In such estimating, the
same person should only be counted once, either  at work or at home.
9.2.2    Quality
         The  physical, chemical  and  biological characteristics of sewage
in cold regions  are  strongly dependent on the type of installation and
the sanitary  facilities provided.  As  described  elsewhere in this manual,
these  facilities can range from "honey bags"  (as described in Section 13)
and buckets to complete equipment  in the home or centralized for community
use.   Table 9-2  summarizes  the sanitary facilities provided at several
cold regions  installations of the  institutional  type.
     TABLE 9-2.  INSTITUTIONAL SANITARY FACILITIES IN COLD CLIMATES
                                         (units per person)
                           Toilets       Urinals       Sinks      Showers
Thule AFB,
Greenland
P Mountain Radar,
Thule, Greenland
50 Man Winter
Camp Tuto , Greenland
Wainwright, Ak*
1/10

1/15

1/10

1/47
1/27

1/45

1/25

0
-

1/8

1/6

1/94
-

1/14

1/10

1/47
 * See Section 11.  This is a central facility for the village.  Plans  exist
   to supplement with home water delivery and "honey" bag piokup.

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                                    9-5
         The grey water/black water  concept  Is  used  at  the  Wainwright,
Ak, central facility and  should  be considered wherever  water  conservation
is an issue (see Section  11  and  Appendix B).  Black  water  is  considered
to be that related  to  human  wastes from toilets,  urinals,  etc.   Grey
water is then  the remaining  wastewater from  showers,  sinks, laundries,
ete.  Table 9-3 summarizes the sources of domestic sewage  from
communities and military  field bases.
      TABLE 9-3.  DOMESTIC SEWAGE SOURCES (% of average daily flow)
                                              Category
Data Source
Bailey [1]
Witt [2]
Jesperson [3]
Given and Chambers [4]*
Flaek [5]
Snoeyink [6]
U.S. EPA [7]
AVERAGE
Toilet,
Urinal
33
26
41
41
33
39
43
37
Shower,
Sinks
33
29
37
16
37
34
38
32
Kitchen
19
14
11
16
4
7
12
12
Laundry
15
30
11
27
26
20
7
19
*Adjusted for conventional  toilets.  Vacuum units  used  in  study.

                    Field Army  Bases (1000-6000  pop)
	(%  of average daily flow)	
Photographic
Aireraft Washrack
Vehicle Washraok
Hospital
Toilets, Shower, Sinks
Kitchen
Laundry
  5
  9
  3
  1
 60
  6
 16
100%

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                                   9-6
9.2.2.1  Concentration of pollutants.  The concentrations of wastewater
constituents will vary with the amount of water used and the type of
facilities employed.  However, the actual mass loading of organics and
related substances should be relatively constant on a per person basis.
Table 9-4 gives estimated mass values for the major domestic wastewater
sources.  The values are based on a comparative analysis of a number  of
data sources.  The final item, "institutional garbage grinders", reflects
the common practice at military stations and many construction camps  of
grinding most of the kitchen wastes for inclusion in the wastewater
stream.
           TABLE 9-4.  ESTIMATED SOURCES OF SEWAGE POLLUTANTS
                       (g/person/d)*
Source                  BOD5         SS         Total N        Total  P
Toilets
Bath /shower
Laundry
Kitchen
Subtotal
Institutional
Garbage Grinders
Total
60.8
5.33
7.92
16.8
90.8
59.0
150
85.2
5.12
7.70
10.9
109
58.8
165
14.7
0.31
0.23
0.49
15.7
1.31
17.0
1.67
0.04
0.67
0.49
2.83
0.95
3.78
*lb/capita/day =  (g/person/d) T 454.

         All the  values in Table 9-4 are independent  of  the  amount  of
water used for a  particular activity.  Combining  these values  with  data
in Tables 9-1 and 9-3 or other sources will allow determination  of
concentrations for a particular case.  Two examples follow:
         a) 200-man construction camp, all conventional  facilities,
            central dining and kitchen with garbage grinder.
            From  Table 9-1:  Assume flow = 220 L/person/d.

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                                    9-7

            From  Table  9-4:                           g/person/d
                                               BOD5       SS      N     P
            Totals  include  toilets, baths,
            laundry,  kitchen, garbage           150	165	17   3.8
            x 200 people =                   30 000    33  000    3400   755
            Total Flow: 220 x 200  = 44  000 L/day.
            Concentrations:      BOD5         30 000  *  44  = 680 mg/L
                                 SS          33 000  f  44  = 750 mg/L
                                 N            3 400  *  44  = 77  mg/L
                                 P               755  T  44  = 17  mg/L
         b) Small community, truck haul,  internal plumbing low volume
            flush toilets (assume  100 people).
            Table 9-1:  flow = 90 L/person/d.
            Table 9-4:               g/person/d
                        BOD5      SS     Total N     Total P
                        91     109       16            3
            Design  concentrations:
            mg/L  =  g/person/d T  L/person/d x 100 mg/g
            BOD5      1011 mg/L
            SS        1211 mg/L
            N           177 mg/L
            P           33 mg/L
9.2.2.2  Temperature.   The temperature  of the  raw wastewater  entering
the sewage treatment  plant can be  an important physical  characteristic.
The efficiency of most  unit operations  and processes  can be strongly
influenced by temperature.  Temperature control is  also  necessary to
prevent unwanted  freezing either in the system or at  the point of final
discharge.
         The energy level represented by moderate (10C) to high
incoming sewage temperatures should be  considered as  a resource.   The
treatment system  and  its protective elements should be designed to take
full advantage of this  available energy.  For  example, the municipal
treatment plant in  Fairbanks, Ak,  extracts energy from the effluent via  a
heat pump and this  is used to heat the  entire  facility.

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                                   9-8
         The temperature of raw wastewater is a function of  the  raw  water
temperature, the water and sewage system design and characteristics,  the
use, number and plumbing (hot water) of buildings serviced,  and  the
ambient temperatures.  Some values for raw wastewater  temperature  are
presented in Table 9-5.
     TABLE 9-5.  RAW SEWAGE TEMPERATURES AT TREATMENT  FACILITY  (C)
    Location            Winter       Summer               Notes
Fairbanks, Ak
Fairbanks , Ak
College, Ak
Eielson, AFB, Ak
Juneau, Ak
Kenai , Ak
Homer , Ak
Dillingham, Ak
Craig, Ak
Kake, Ak
Soldofna, Ak
Eagle River, Ak

Eagle River, Ak
0
11.8
18.9
21.7
2.2
8.0
3-5



3










3-4
5
4

5

9
2.8
10.9
18.3
20.7
8.9
10-14
9-10



8-9



Individual wells
Water main at 15
Sewers in heated
Sewers in heated



April
January
December

Initial operation
services
After 4 years

C
utilidor
utilidor







, few


Inuvik, NWT
Whitehorse, YT
Clinton Creek, YT
       3-15
17
23
22
Water main bleeders
Emmonak , Ak

Alaska

Hay River, NWT
9.2.3 Flow variation
28

20-24

10-15

Central facility, grey
water only
Construction camps
( Alyeska)
Airport facility

          Institutional  facilities  in  cold  regions,  such as military
stations  and  construction camps, tend to have  strong  flow variations
because a large  portion of the  population  responds  to the same schedule.
The  peak  flow will  usually occur in late afternoon  when personnel are
using  the bath and  laundry.  Two such peaks  will occur at those installa-
tions  operating  on  a  continuous two-shift, 24-hour  cycle.  The peak daily
flow rate for design  purposes should  be  three  times the average daily
rate for  institutional  facilities.

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                                    9-9
         Civilian  communities and  similar  residential  areas  have  less
sharply defined  flow variations.   In  general,  a  single major peak,
approximately at mid-day  will occur.   The  time is  dependent  on trans-
mission distance from  the homes to  the  treatment system.   The daily peak
flow rate of these  communities should  be taken as  two  times  the average
daily rate.  The U.S.  Public Health Service  uses a factor  of 3.5  for
designs in small communities (see  Section  3.4).
         Minimum flow  rates are important  to  the design of grit chambers,
monitoring devices,  dosing equipment,  etc.   A minimum  rate equal  to 40
percent of the average rate should  be  used for design  purposes.
9.3      Unit Operations
         Practically all  of the unit  operations  used in wastewater
treatment are affected by temperature  through viscosity changes in  the
water and/or changes in chemical reaction  rates.   An analysis during
early design stages  is necessary to predict  the  thermal status of major
components in the  system. If warm  sewage  is  expected  and  the entire
system is to be housed in a heated  building,  then  conventional temperate
zone practice can  be used.  If cold sewage is  expected or  significant
temperature changes  are predicted within the  system, then  adjustments
will be necessary  in the  design of  unit operations as  described in
subsequent sections.
9.3.1    Mixing
         Mixing is an  important function in waste  treatment.   It  is
required for flocculation, for the  continual  suspension of solids in
liquids such as the  mixed liquor in activated  sludge,  and  for dissolving
solids.  All of these  mixing activities are  strongly dependent on
temperature because  of changes in the viscosity of the liquid. Figure
9-1 can be used to make the necessary adjustments  in design  criteria for
temperature-induced  viscosity changes.  Further information  on mixing can
also be found in Section  4 since the general  requirements  are the same
for water and wastewater.
9.3.2    Sedimentation
         The settling  of  discrete particles in water is affected  by the
viscosity of the water.   This is a  factor in grit  chambers and in primary

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                                   9-10
settling tanks when flocoulant chemicals are not used.  Detention  times
must be increased to compensate for lower settling velocities  in colder
water.  The multipliers on Figure 9-1 ean be used to adjust design
detention times.  The temperatures shown are for the fluid and  not the
general air temperature.  Alternatives to adjusting design detention
times include housing the tanks in a heated enclosure and/or preheating
the incoming fluid.
         The settling of higher concentration  flocculant  particles is not
as strongly affected by temperature.  As shown  on Figure  9-2,  at concen-
trations of 2000 mg/L or less, temperature-induced viscosity effects are
quite strong.  At 6000 mg/L and higher, the concentration of particles
present has a greater influence than fluid temperature.   The multipliers
shown on Figure 9-2 can be used for the design  of settling tanks and
thickeners.  Values for sludge concentrations  not shown can be determined
by interpolation.  Figure 9-2 demonstrates that settling  units, such as
upflow clarifiers, tube settlers, eta, which are designed for  relatively
high  sludge concentrations, will  require the least  size adjustment for
low-temperature operation.
         Density currents must also be considered in the  design of
settling tanks and thickeners.  If the incoming fluid  is  significantly
different in temperature than tank contents, short  eircuting and/or
excess solids loss may occur.  Protective elements  should be employed  if
necessary to maintain the temperature of tank  contents as elose as
possible to that of the incoming  fluid.
9.3.3    Filtration
         Filtration of wastewater is affected  by temperature-indueed
viscosity changes.  The multiplier values from Figure  9-1 should be used
to reduce filtration efficiency.   Further details on  filtration oan be
found in Section 4 since basic criteria are common  for both water  and
wastewater.
9.3.4    Gas transfer
         The solubility of gases  in water increases as the  temperature
decreases.  Air, oxygen, and  ehlorine are the  commonly used gases  in
wastewater  treatment.  The efficiency of aeration and  other gas transfer

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                                       9-11
                      1.75r
                     1.00 -
                     0.00
                        f\  i  i
                                   5        10        15

                                       Temperature (C)
                                                        .  . ^
                                                           20
                     FIGURE 9-1. VISCOSITY EFFECTS VS  TEMPERATURE
0)

"3.
     2.00
     1.75  *
1.50
         35
                       40
    Temperature (F)

45        50        55
60
                                    Temperature (C)

             FIGURE 9-2   SETTLING DETENTION TIME VERSUS TEMPERATURE

-------
                                 9-12
operations should, in theory, be greater with low temperature wastewaters.
However, the viscosity of the water also increases as the temperature
decreases.  This decreases the number of contacts between gas bubbles and
water molecules.  These two factors tend to compensate for one another,
so the net practical effect is little improvement in overall gas transfer
efficiency with low temperature wastewaters.  Section 4.2.9 provides
additional detail on aeration.
9.3.5    Adsorption and chemical reactions
         Adsorption occurs in biological processes as well as in physical/
chemical treatments with activated carbon.  The rate of adsorption, as
defined by the Gibbs equation, is inversely proportional  to temperature,
so adsorption should be more rapid at low temperatures.   However,  the
increased viscosity of the water at low temperatures has  the same  effects
as described above so there  is no practical improvement in efficiency.
         Both metabolie and  chemical reaction rates tend  to be  slower  at
low  temperatures.  These effects must also be considered  in preparing
chemical solutions for use in wastewater treatment.  The  solubility of
most chemicals decreases as  the water temperature  is lowered.   Table 9-6
gives  some representative values for typical  treatment chemicals.
9.4      Unit Processes
         Processes for preliminary, primary,  secondary and advanced waste
treatment are based on the unit operations or combinations thereof
previously discussed.  This  section will only consider  those  faetors of
special  significance  in eold climates.
             TABLE 9-6.  VARIATION  IN SOLUBILITY  OF  TYPICAL
                         CHEMICALS WITH TEMPERATURE  (grams/litre)*
                                              Temperature
Chemical
Alum
Ferrous sulphate
Sodium hydroxide
Calcium hypochlorite
0C
723
60
287
215
20C
873
120
527
228
 * grams/litre x 0.00834 = Ib/gal

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                                  9-13
9.4.1    Preliminary treatment
         This can include  screening, grit and  scum  removal  and  grinding
or comminution.  The latter can be a component,  such  as  grinder pumps, in
pressure sewage transmission  systems discussed  in Section 7.  The  use and
proper maintenance of grease  traps at appropriate locations,  e.g.,  institu-
tional kitchens, is absolutely essential for the successful  operation of
treatment processes as well as collection systems in  cold regions.
9.4.1.1.  Screening.  The  basic design  for  trash racks and  bar  screens
is not different in cold climates.  Since storm waters are  usually
excluded from cold regions sewer  systems the channel  design  for screens
or racks can be based on wastewater flow rather  than  storm water flow.
In the arctic and subarctic it will be  necessary to enclose  the facility
in a shelter to avoid icing problems and provide easy access  for opera-
tion and maintenance.  If  warm sewage is expected it  may not  be necessary
to provide supplemental heat  for  an insulated  enclosure. Condensation
and icing may occur on the inner  surfaces of exterior walls  so  materials
and coatings should be selected accordingly and mechanical  or electrical
controls located elsewhere.
9.4.1.2  Grit and scum.  Designs  for grit chambers, flotation chambers,
and grease traps are also  similar to temperate  zone practice.  Detention
times should be increased  for low temperature  sewage  as  described  in
paragraph 9.3.2.  Protective  enclosures will be  similar  to  those
described above under 9.4.1.1.  Problems with  grease  traps are  not unique
to institutional facilities in cold climates,  but special attention
should be given to their location and proper maintenance.
9.4.2    Primary treatment
         The design detention time for  settling  during primary  treatment
will require adjustment as described in paragraph 9.3.2. If  soil
conditions permit, settling tanks should be designed  in  the  conventional
manner as partially buried structures.  The presence  of  permafrost,
particularly as ice-rieh,  fine-textured soils, will require  above-ground
tanks and/or special foundations.  Temporary covers are  recommended for
buried tanks for winter operation in the Arctic and subarctic.   Tanks

-------
                                 9-14
above grade will require sidewall insulation and covers,  or  enclosure  in
a protective structure.
9.4.3    Biological processes
         Systems which have been successfully used  in  cold climates
include:  lagoons, both facultative and aerated, activated sludge
variations, and attached growth systems.  Each has  special requirements
for successful cold region performance.
9.4.3.1  Facultative lagoons.  Where  sufficient land area and  suitable
soil conditions exist, facultative lagoons are probably the  most
cost-effective alternative for cold regions.  The major responsible
factors are simplicity, and economy of construction and operation.
         Facultative lagoons should be designed for a  BOD loading  of up
to 3.7 kg/ha.  Winter performance in  cold climates  is  reduced  because  of
ice and snow cover and low temperatures and is roughly comparable  to
primary treatment.  Total retention during this period is often  required.
Controlled discharge from such ponds  in the late spring and  early  fall is
a common practice in Canada and the north central U.S.   Two  or three
cells are commonly used to avoid short circuiting.  Figure 9-3 illustrates
a typical two-cell arrangement.  Figure 9-4 illustrates the  use  of a
stop-log manhole for depth control.
         The amount of ice cover to be expected on  a facultative  lagoon
can be predicted by the method described in Section 5.   If sufficient  data
are not available for such calculations a depth of  1 m should  be  assumed
for most subarctic locations.  The design depth should be based  on winter
conditions and allow 30 cm of freeboard, plus the ice  thickness,  plus  1.5
m from the underside of the ice to the lagoon bottom.   Maximum depth
during the summer period would be 1.5 m as maintained  by the stop-log
manhole.
         Supplemental aeration may be needed for sueh  lagoons  in  very
special oases.  Examples might be where fish canning,  animal slaughter or
other food processing imposes a brief but intense loading on the  lagoon
during the summer months.  In these cases small floating aerators  or
similar devices can be used during the period of concern and removed for
the balance of the year.

-------
                                    9-15
             Raw sewage
               Effluent
                                    PIPING DETAIL
                                          Cell 1
                                    Valve
                                     Cell 2
         Stoplog manhole
            (Figure  9-4)
r                                     1
                             *Y~
                                     T
  SERIES OPERATION
PARALLEL OPERATION    ISOLATE AND DISCHARGE
        FIGURE 9-3.  TWO-CELL FACULTATIVE LAGOON FLOW  CONTROL
                                      Valve box and valve stem extension
                                         Frost heave protection       |ce cover.
                    Gate valve
            Maximum frost penetration
      Insulated, electric heat traced pipe
                        2-3
                            Upturned elbow -
                              Anchor block 

              Frost heave protection if required
                        Insulated cover
                                                                Ice cover 
                                                  '''.'' .' .".''/ ' '/0v]^NSi^i-z---r--------
                                                  L"        '    -."-. "-:oy??%cL.-_---r-_H
Concrete pad or rip-rap
                                                       Gate valve
                            40mm
                              Calking as required
                                  Adjustable stop logs
                                       Detail
       FIGURE  9-4.   STOP-LOG  MANHOLE

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                                 9-16
         Standard temperate zone construction techniques can be  used
except where permafrost is present.  Permafrost consisting  of  fine-
textured, ice-rich soils should be avoided because  thawing  can result  in
failure or at least frequent repair and restoration of dikes and berms.
         Lagoons can be constructed in permafrost that is  physically
stable after thawing.  In this case a two-stage operation  has  advantages
if time permits.  The first stage is limited  to stripping  the  vegetation
and topsoil from the lagoon area.  Actual  eonstruetion can  begin when
thawing has progressed to a suitable depth.   Construction  techniques  for
dikes and berms, and the use of lining materials, are  the  same as
described in Section 5 for water  storage.
         The shape of the lagoon  can affect  performance  by influencing
short circuiting and mixing.   In  general,  square  or rectangular  cells
where the length is not more than  three times the width  are preferred.
The corners should be rounded  in  both cases.   On  occasion  it is  possible
to take advantage of existing  topography  and  use  a  natural depression or
swale with minimum construction;  even the use of  an existing pond might
be considered.
9.4.3.2  Aerated lagoons.  These  systems  require  less  land area, more
energy and more operational and management attention than  facultative
lagoons.  Systems in use  in eold  climates range from low-intensity
systems where  algae may  still  be  a factor to high-rate well-mixed units
whieh are really a variation of aetivated sludge.   Only the partial-mix,
low-intensity  systems will be  considered  in detail  in  this section
because  of  their lower  energy  and O&M requirements.
         Basic process  design  criteria  are similar  to  those used in
temperate  zones.  Design is based on:
 where:   Se = effluent BOD (mg/L),
         S0 = influent BOD (mg/L),
          t = detention time (days) = ,
                                      Q

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                                 9-17
         V = volume of basin,
         Q = daily flow,
         K = overall reaction coefficient (base e).
             winter (0.5C)   = 0.14
             summer (16-20C) = 0.28
For basins in series, the equation becomes:

         Se =    1                                        (9-2)
         S    _ ,  KtvN
          o   (1 + )

where: N = number of basins.
This can be transposed to:
         Kt = N
                       N
- 1
(9-3)
         Using the specified K values, the BOD values required  for  a
particular design, and a range of N values (1-4), equation  (9-3) can be
repetitively solved to determine the optimum number of basins.   In
general, winter conditions govern the number and size of basins, and
summer eonditions are critical to adequate oxygen transfer.
         The effective treatment volume must reflect ice cover  in the
winter and sludge accumulation on a year-round basis.  Ice  will  not
form continuously over the entire surface.  Even in extreme weather there
will be small areas of open water where air will bubble to  the  surface
from the submerged aeration system.  Aerated lagoons in central  Alaska
(freezing index >2800C-days) have been designed for a 30-om
winter iee cover.  A single-cell lagoon near Anchorage, Ak, (freezing
index 1250C-days) receiving warm sewage has a 5-om observed winter
ioe cover.  If specific values are not available, an assumed factor of
15% for depth of ioe cover is recommended.  A factor of 5%  is commonly
used to allow for sludge accumulation on the bottom.  The lagoon volume
required for winter treatment must be in addition to both of these
factors.

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                                 9-18
         A design for minimal heat loss would include vertical sidewalls
but this increases construction costs.  Sloping sidewalls (1:2 or 1:3)
are most common.  A square configuration with rounded corners is recom-
mended to minimize heat loss and hydraulic short circuiting.  The
dimensions of such a basin can be determined as shown on Figure 9-5.
         Some form of submerged aeration is generally used; floating
aerators and other surface devices create icing problems.   Inlet and
outlet structures are similar to those described previously for
facultative lagoons.  The oxygen requirements for aeration design are
based on summer conditions when biological activity is at maximum rate.
For partial-mix lagoons the oxygen required is usually specified as
double the organic loading:
         02 = (2) (BOD) (Q) (10-6)
where:   02 = kg/day oxygen required,
        BOD = influent BOD5 (mg/L),
          Q = flow (L/d).
         Under  standard conditions,  air contains approximately 0.28
kg/m3 oxygen.
                .  J , 3/  .           (2) (BOD) (Q) (10~6)
       Air Required (nrYs) =    	L^d		
                                (E)  (0.28 kg/m3)(86 400  s/d)

                                8.27 x  IP"11 (BOD) Q
                                           E

where:  E = aeration efficiency,
        m3/s x  35.31 = cfs.
         The aeration efficiency depends on a number  of  factors  such as
depth of basin, type of diffuser, mixing turbulence and  basin
configuration.  The E value for partial-mix lagoons with submerged  tubing
is  approximately  16%.  For a  typical case with a  raw  sewage BOD  of  240
mg/L and a flow of 10^ litres per  day,  the air requirements would  be:
                    -  (8.27 x 1Q-H)(240 mg/L)(105 L/d)
        A.
        Air
                     =  0.012  m3/s.

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                                9-19
Calculation of basin volume for any rectangular basin
with sloped sides and round corners

Sd


 	 	 a '
b
                              \
 Volume  = V = d [(a + Sd) (b + Sd) + .0472 S2 d2]

 Note:  The last term (.0472 S2 d2) can
       be dropped for preliminary estimates
                   FIGURE 9-5.  DIMENSIONS OF LAGOONS

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                                  9-20
         Figure  9-6  illustrates the air and power requirements  for a 3-m
deep partial-mix aerated  lagoon.
                          Organic load (kilograms BOD5/day)
                         100            200            300
         20
         15
      03

      I
      55  10
      J3
      QQ
                                                                 800
                                        00
                                        "co
                                                                 600  \
                                                                     ON
                                    400  |
                                        03
                                        CT
                                        03
                                    200  <
                       1000
       2000
     Population
3000
                                                              4000
   FIGURE  9-6.   POWER AND AIR REQUIREMENTS FOR 3-m  DEEP  PARTIAL-MIX
                 AERATED LAGOON
         Table  9-7  summarizes the characteristics of  typical  aeration
equipment  for cold  climate partial-mix lagoons.  An ice  cover will form
over  such  lagoons  in the winter.  However, eve.n under extreme temperature
conditions there is sufficient open water for the applied  air to exhaust
to the atmosphere.   Protective and heated housing will be  required for
blowers, pumps,  and related controls.  Such enclosures must  provide an
external air  intake for the blowers but preheating  of the  air is
unnecessary.
         TABLE 9-7.   CHARACTERISTICS OF TYPICAL AERATION EQUIPMENT
                                  02*
Equipment	(kg, Standard Conditions)	
                              Common Depth**
                                  (m)
Submerged  Tubing
Air  Gun
Helical  Diffuser
0.3-1.0/100 m
0.4-0.7/unit
0.5-1.9/unit
               1-3
             3.5-6
             2.5-4.5

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                                     9-21
          Summertime algae blooms will occur in these partial-mix ponds
throughout the Arctic and subarctic.  The requirements of federal and/or
local regulatory agencies with respect to removal of algae must be
determined prior to design for a specific site.  Techniques for algae
removal are available, and the criteria are not unique to cold regions.
Addition of algae-removal equipment to an aerated lagoon will increase
costs and complexity, and possible resit in the selection of some other
basic process for treatment.  Typical cost relationships for lagoons in
Alaska are given in Section 9.7.
9.4.3.3   Activated sludge variations.  Systems in use in cold regions
include conventional and oxygen activated sludge, contact stabilization,
extended aeration and oxidation ditches.
          Many of these systems are enclosed in heated structures and
receive warm sewage on a year-round basis.  Basic process design criteia
for these situations are no different than conventional temperate zone
practice.
          Speecial attention must be given to system details, appurtenances
and process controls.  The humidity inside such buildings will be quite
high due to exposed water surfaces'.  Condensation and icing can occur on
inner surfaces of exterior walls, doors, and windows.  Control panels and
similar elements should be located away from such surfaces to avoid water
and/or ice damage.
          Ventilation of such structures is necessary, but the impact of
the exhause on the adjacent community must be considered.  Ice fog can be
created under extreme conditions, resulting in aesthetic and safety
problems.  Dehumidification or heat recovery with induced condensation
will control the problem.
          Systems that are exposed to the weather and/or expect to receive
low-temperature wastes may require modification of basic design criteria
in addition to the general factors discussed above.
          Conventional or oxygen activated sludge and contact
stabiliation .   These types of systems will probably be enclosed, but in
either case they may receive low-temperature wastewaters.  Reaction rate
coefficients are presented in Table 9-8 for use in the equation:

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                                 9-22
      TABLE 9-8.  TEMPERATURE COEFFICIENTS FOR BIOLOGICAL TREATMENT
                                                      Temperature Range
Process
Oxidation Pond
Facultative Lagoon
Anaerobic Lagoon
Aerated Lagoon
Activated Sludge
Extended Aeration
Trickling Filter (conventional)
Biofilter (plastic media)
Rotating disc
Direct filter recirculation
Final effluent recirculation
Final effluent recirculation
6
1.072 - 1.085
1.06 - 1.18
1.08 - 1.10
1.026 - 1.058
1.00 - 1.041
1.037
1.035
1.018
1.009
1.009
1.032
C
3-35
4-30
5-30
2-30
4-45
10-30
10-35

10-30
13+
5-13
         Significant ice formation must be avoided  in  the aeration compart-
ments of these systems.  An ice cover will inhibit  atmospheric aeration
and will entrap mixed liquor solids.  Both factors  may reduce treatment
efficiency.  Tank design should provide minimum exposed  surface  area.
Evaporation from liquid surfaces and the cooling effect  of  the wind  are
major factors in winter time heat loss.  An unheated protective  shelter
over the tanks will reduce both and allow satisfactory performance.  An
alternative would be temporary tank covers and wind breaks  during the
winter period only.
         Settling tanks and clarifiers associated with these  systems
should receive protection to reduce heat loss and inhibit formation  of
density currents.  Protective elements in the northern temperate zone can
be limited to those required for operator safety (prevent icing  on walls,
ladders, etc.), and to overflow weirs and scum removal points where
freezing is most likely to occur.
         Extended aeration systems are available as prefabricated "packaged*
units of up to 3800 m^/d capacity.  Smaller sizes are  also  available
completely installed in a prefabricated shelter ready  for direct installa-

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                                  9-23
tion.  Basic process design criteria are comparable  to  temperate  zone
practice if warm sewage  is to be received at an  enclosed  and  heated
treatment unit.
         It is not necessary to provide a continuously  heated  building  to
maintain treatment efficiency; operator convenience  and comfort are  the
only justifications for  such energy inputs.  If  the  incoming  raw  sewage
is about 10C or warmer  there is sufficient heat in  the liquid  to
sustain the process.   Protective elements (i.e., tank covers,  burial,
wind breaks, unheated  shelters) are useful to  reduce heat  losses.  A
stand-by heat source is  also recommended for emergency  situations.
         Extended aeration systems have been successfully  operated with
mixed liquid temperatures of 1 to 5C, producing  effluent  EOD^ and
SS of secondary quality.  Mixed liquor concentrations tend  to  increase
more rapidly under these conditions so more frequent sludge wasting  is
required.  Design organic loadings (F/M ratio) of  up to 0.08  g  BOD/g
MLSS/day and MLSS concentrations of 3000-4000  mg/L are  recommended for
low-temperature operation.  Pumps, motors, blowers,  external  piping,
valves and similar appurtenances require protective  enclosures  and heat.
         Design of these units for military and  construction  camps must
consider the potential for intermittent loading  and  strong  fluctuations
in population.  Equalization tanks can damp out  strong  daily  variations
in flow.  Where regular  population changes are expected the design can
provide two or more smaller units for parallel operation under  peak
conditions. Only one unit would be operated under  low flow  conditions.
         These small-scale systems are particularly  sensitive  to  situa-
tions created by water system bleeding and/or  infiltration  in  the community.
Either ean hydraulically overload the system.  ' The potential  for  these
conditions must be evaluated prior to design.  It must also be verified
that the capability will exist to operate the  type of system  proposed.
         Oxidation ditches have been successfully used  in  subarctic
Alaska.  Basic process design criteria are similar to practice elsewhere.
Design for low-temperature operation should conform  to extended aeration
criteria given above.
         Modifications to temperate zone configurations are required to
reduce heat loss.  As shown on Figure 9-7,  vertical  side walls and a thin

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                                 9-24
          Brush housing (see detail)
                 SECTION A-A
Co
'j"',
.;';' S.
3 '
' ",'
o''v:
nc

;rete  ^
WLV
,_~~__~_~~ ~~_ ~~_ ~~_ ~
^Z-Z^-ZO

-,


V
	
-z-z-z-z-z-z

q


. i) ' .' '*'.- '&
o'- ' , '.'
/aV

BRUSH HOUSING
                                              Air vent
                                         Neoprene skirts
                                                 WLy
                                              -_-: Flow
               FIGURE 9-7.   OXIDATION DITCH FOR SUBARCTIC
vertical centre island  reduce  surface area  and  heat loss in the ditch.
Also shown on the same  figure  are  the protective housing neoprene
skirts to prevent icing around  the  brushes.   The clarifier units for such
systems should be enclosed  but  need  not  be  heated.   Cautions regarding
location of controls, etc.,  on  exterior  walls should be observed.
         These systems  are  potentially applicable over the same range
previously indicated for  extended  aeration.   They can be constructed
on-site and attempts at prefabrication have been made in the past in the
smaller sizes.  All the cautions and limitations previously indicated for
extended aeration apply.
9.4.3.4  Attached growth  systems.   These would  include rotating
biological discs, trickling filters, and similar devices with plastic,
rock, or wooden media.  Since  they depend on a  thin film of water for
treatment they are susceptible  to  freezing.   Units are, therefore,
generally enclosed in a heated  structure.  However, if low-temperature
wastewater is expected, the reaction rate coefficient from Table 9-8
should be used for design.   Clarifier tanks  need not be heated but should
be protected as described in pervious paragraphs of this section.

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                                  9-25
          Configuration of these systems follows temperate zone practice,
 with some form of preliminary clarification and final settling with
 recirculation common.   Basic process  design criteria are not unique for
 cold climates.  Adjustments to the design rates for low-temperature
 wastewater  should be made using the 6 values in Table 9-8.
          Limited experience with disc systems to date tends to indicate a
 greater  level of system reliability with a lesser level of  energy and
 operator skill compared to complete-mix biological or physical/chemical
 treatments.   They can  also be designed to provide nitrification in
 addition to  BOD and  suspended solids  removal.
 9.4.3.5   Physical/chemical processes.  The biological systems described
 in  previous  paragraphs are capable of secondary treatment at best.
 Physical/chemical systems, depending  on the units in the process, can be
 designed to  produce  almost any level  of effluent quality desired.  In
 most  applications they are used to achieve a high level of  organic and
 solids removal and/or  nutrient removal.  As in temperate zone practice,
 they can either  follow preliminary biological treatment or  the entire
 process  train can be physical/chemical.  It is conventional practice, in
 all  climatic  zones,  to install such units in heated buildings.  Basic
 process  design is not, therefore,  unique  to cold regions, except when
 low-temperature  sewage is expected.   Adjustments can then be made as
 described in  Section 9.3.   An alternative is to  warm the raw sewage in an
 equalization  tank in a heated structure.   This will stabilize and enhance
 performance of the system.
          These units were selected for most of the camps during construc-
 tion  of  the Alaska pipeline.   Advantages  claimed included:   minimum space
 requirements;  minimum  site  impact  during  construction and restoration;
 consistant high  quality performance;  and,  operation could be matched  to
 varying  flow  or  organic  loading.   Disadvantages  observed during operation
 included very high costs  due  to  intense labour  requirements,  chemicals
 and energy.
         Estimated chemical costs  for  a typical  95 m^/d  system ranged
 from  $0.32 to  $2.33  per  1000  L.  A comparison  of annual  costs,  manpower
and energy is  given  on Table  9-9.   The  two  systems compared  are capable

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                                  9-26
of producing  generally  equivalent effluents  since  the  physical/chemical
units were only designed  for organic  (i.e.,  BOD) and suspended  solids
removal, not  nutrients.
       TABLE  9-9.   COST COMPARISON -  CONSTRUCTION  CAMP WASTEWATER
                    TREATMENT SYSTEMS*  (1976  $)
Process
Extended Aeration-'-
Capital Equipment
Parts and Chemicals
Physical Chemical^
Capital Equipment
Parts and Chemical
Amortized
Annual Costs
Equipment and Mtl.
($1000)

30.6
11.4-14.8

31.3
19.4-71.9
Manpower Energy
(MH/day) (kW/day)

5-10 180


24 400

* 95 m3/d for Alaska pipeline construction camps
  with:  6-hr equalization, pumps, blowers, aerobic digestor,
           chlorination.  5-year life @ 15%.
2
  with:  12-hr equalization, pumps, blowers, centrifuge, chemical feed,
           chlorination.  5-year life @ 15%.
         Based on experience to date, physical/chemical treatment should
only be considered if very high effluent requirements exist in conjunc-
tion with site conditions that preclude other forms or combinations of
treatment.
9.4.3.6  Land treatment processes.  These concepts are capable of very
high levels of treatment depending on the process and operational mode.
In addition to normal organics and suspended solids, removal of
nutrients, metals, bacteria and virus are possible.
         Basic process design criteria are similar to those used in
temperate regions since these already include factors for general weather
conditions and low-temperature periods.  The land treatment component is
usually preceeded by some other form of treatment, typically a lagoon.
Depending on the concept, additional storage may be required for
inclement weather or other seasonal constraints.  Treatment and storage
functions can be combined in a multi-cell facultative lagoon.

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                                  9-27
         The  practical  range  of  land  treatment options is limited in
permafrost regions.   Shallow  permafrost  and  extreme winter temperatures
limit  the horizontal  and  vertical movement of  water in the soil profile.
During  the summer  it  would  be possible  to operate  an overland flow
process under  the  conditions  described.  Basic process criteria would be
similar to temperate  zone practice.   During  the operational period high
removal efficiencies  for  BOD,  SS, nitrogen and metals are possible with
moderate removal of phosphorus expected.  However,  an alternate discharge
or storage would be necessary for most  of the  year.
         Slow  rate land treatment is  feasible  anywhere in the cold
regions where  silviculture  or agriculture is practiced.   The wastewater
is sprinkled or spread  on the ground  surface and the vegetation is a
component in the treatment  process.   The percolate  can be recovered for
reuse or allowed to move  into the groundwater.   The operational season is
limited to the period of  unfrozen surface soil  conditions.  Peak perfor-
mance is attained  during  the  growth period of  the vegetation.  Percolate
of drinking water  quality can be achieved in a properly designed and
operated system.   Alternative discharge  or storage  would be required
during  the period when  surface soils  are frozen.
         Rapid infiltration has  the greatest promise for cold climates.
It depends on  relatively  high rate applications on  relatively coarse-
textured, free-draining soils.   These can be found  throughout cold
regions in alluvial river valleys and coastal  areas.  Very high BOD, SS,
bacteria, virus and phosphorus removal  can be  achieved,  and moderate
nitrogen removal depending  on the mode of operation.  Rapid infiltration
can also be operated  on a year-round  basis in  some  locations so extensive
storage is not needed.  Treatment to  primary effluent quality is needed
to avoid rapid clogging of  the soil surface.   A facultative lagoon would
more than suffice.  Operation is similar to percolation  ponds except that
a number of beds, or  cells, are  alternately flooded and  dried to improve
treatment and  prevent clogging.
         A thorough site  investigation is required  to ensure that the
applied wastewater will enter  the soil and move down and away from the
application site.  Experience  is limited in the arctic  and subarctic and

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                                 9-28
optimum criteria are not available.  Pilot tests are  recommended  for
large-scale operations.  Experience in northern New England  suggests  a
value of approximately 111 000 m^ per year as a conservative  estimate
of annual application.  That would require one hectare  of  basin  surface
for every 750 m^/d of wastewater flow.
9.4.3.7  Disinfection.  The need for and  the degree of  wastewater dis-
infection to be achieved, and often the agent to be used,  are specified
by the regulatory agencies of concern.  Typical coliform contents of  cold
regions wastewaters are shown in Table 9-10.  Chlorination is the most
commonly used technique in the cold regions but lime  has also been
tested.  Basic process criteria are similar to temperate zone practice
with respect to contact time and properly baffled  chambers to prevent
short circuiting.  The selection of either gas or  hypochlorite as the
chlorine source and the related safety measures also  follow standard
practice as modifed by logistical resupply problems for many cold regions
locations.
  TABLE 9-10.  TYPICAL COLIFORM CONTENTS  IN COLD REGIONS WASTEWATERS*
Waste Type
Weak Sewage
Holding Tank Effluent
Honey Bags
Lagoon Effluent
Typical
Location
Dawson
Aklavik
Aklavik
Inuvik
L/person/d
5915
68
1.3
545
Total Coliforms
number/100 ml
1.0 x 105
1.0 x 107
5 x 108
1.0 x 105
* Source:   International  Environmental  Consultants,  Report on
            Alternatives  to  Disinfection (1978).
         Erosion  type  chlorinators  have  been  used  at small remote facili-
ties in Alaska.   It  is sometimes  difficult  to maintain a specified
dosage but  they offer  operational simplicity.  They should be housed in a
separate compartment constructed  of noncorroding materials, along with the
tablet supply  in  a  sealed  container.  In the  past, extreme corrosion of
metals and  mechanical  parts  has occurred when exposed to the humid
atmosphere  of  an  enclosed  treatment plant building.

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                                 9-29
         Effluents from lagoons and other exposed treatment  units will be
at or near 0C under extreme winter conditions.  Some  thermal  protec-
tion for the contact chamber is therefore essential.
9.4.3.8  Sludge.  Only in-plant sludge management is discussed  in this
paragraph.  Final sludge disposal is described in Section 13.
         Large-scale conventional facilities, and those operating within a
heated environment can be expected to produced sludge  at rates  similar to
conventional temperate zone practice.  Typical values  are summarized in
Table 9-11.
         Aerobic treatment systems designed for low-temperature operation
will tend to generate sludge at a rate similar to moderate temperature
units but, because of lower metabolic activity, cannot oxidize  it as
fast.  There will, therefore, be a higher rate of accumulation  in the
winter than experienced in conventional practice.  As  a result, winter
               TABLE 9-11.  TYPICAL SLUDGE PRODUCTION  RATES*
Process                             Dry Solids           Solids Content
                                   g/person/day          of  Wet Sludge
Primary Settling
Trickling Filter
Secondary
Primary plus T.F.
Secondary
Primary plus high-
rate Activated Sludge
Conventional Activated
Sludge Secondary
Primary plus conventional
A.S. Secondary
Extended Aeration
Secondary
Lagoons
54
18
72
82
32
86
40
60
6
4
5
5
0.5-1
2-3
2
20**
*  Average 24-hr values, from temperate climate experience.
** High value due to long-term consolidation of sludge on lagoon  bottom!
   Data from partial-mix aerated lagoons in Alaska.

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                                 9-30
sludge wasting from exposed extended aeration plants will be required
about twice as frequently as in more temperate climates.
         Temperature inhibitions on digestion increase  the rate of  sludge
                                                               O
accumulation in all types of lagoons.  Values of 0.25 to 0.40 mj/1000
people/d have been reported for sludge accumulation in  cold climate
facultative lagoons.  Sludge will also accumulate at a  faster rate  in
aerated lagoons and available data indicates that the assumption  of  5%  of
total lagoon volume for sludge (9.4.3.2) is conservative, so that
cleaning and sludge removal might be required on a 10-15 year cycle.
         The accumulation of undigested winter sludge imposes a high
oxygen demand on a lagoon when liquid temperatures warm up in the spring.
Supplemental surface aeration may be helpful for odour  control during
this period.
         Procedures for sludge digestion follow temperate zone practice.
It is necessary to provide additional heat and/or insulation to maintain
anaerobic digestion in cold climates.  Burial of digester tanks is  common
in the subarctic to provide natural  insulation.  Aerobic digestion  is
less temperature-sensitive but produces a less stable product.
         Dewatering of sludge prior  to disposal also  follows conventional
temperate zone practice.  One exception is the use of natural  freeze-thaw
cycles for dewatering.  If sludge is flooded on exposed beds and  allowed
to freeze, the solid particles will  settle readily upon thawing.
Approximately 50% of the  total volume can be decanted from  the beds as
supernatant and returned  to the treatment plant.  The thickened  sludge
can  either be left on the beds for complete drying or disposed of
directly.
9.5      On-Site Treatment
         These systems might directly serve a  single  dwelling  or  a
cluster of dwellings.  Any system that does not depend  on centralized
collection and treatment  for an entire community  falls  in  this eategory.
Discharging systems such  as septic  tank/soil adsorption combinations,  or
low  to no discharge units represented by a variety of toilet  units and
recycle systems, are included.

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                                  9-31
9.5.1    Systems with discharge
         Septic tanks and similar units fall in this category.   Basic
process design criteria are similar to those used in temperate  zones.
Section 10 discusses special aspects of cold climate septic  systems.
         Small-scale aerobic units, usually based on the extended
aeration process, are available for individual dwellings or  clusters of
dwellings.  These are generally heated and housed so design  is  conven-
tional.  If properly operated these units can, in theory, achieve  secon-
dary quality effluent and could, if allowed by the applicable regulatory
agency, be designed for point discharge to surface waters.   If  properly
operated, the reduction in BOD and suspended solids achieved would  permit
effluent disposal in a leach field smaller than that required for  septic
tank effluents.  In all cases, the critical aspect is proper operation,
plus a method for positive solids separation and solids disposal.
General experience has shown that neither the average homeowner or
similar personnel have the competence and dedication required to service
such units.  They should only be considered if some permanent provision
can be made for management and maintenance of the units on a regular
basis by some outside authority.
         Intermittent or seasonally occupied facilities are  common  in
cold regions.  Several arrangements are available for small-seale  opera-
tions either with or without discharge.  In the former ease, a  small
physical/chemical packaged plant ean be run intermittently and  still give
satisfactory removal efficiencies.  Operator skills, resupply and  sludge
management ean be problems.  For a small facility a two-eell, controlled-
diseharge pond, operating in parallel might be suitable.  Residence time
prior to discharge would be a full year.  If occupancy is only  in  the
warm summer months, an evapotranspiration bed preceded by a  septic  tank
or aerobic unit will provide a no-discharge system.  Design  would  be the
same as for a temperate zone location, with inclusion of climatic data
specific to the site and consideration of permafrost under the  bed.
9.5.2    Low or no discharge systems
         These include pressure or vacuum toilets, vault toilets, and a
whole variety of toilet units for the individual home based  on
electrical, mechanical or biological proeesses.

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                                  9-32
         Low water use toilets, as well as other conservation devices,
reduce the volume of liquid to be managed but not the mass of pollutants.
The same is true of separation of waste streams into "black" and  "grey"
water.  Both streams require comparable treatment even  through  the  total
volume may be reduced.  Although the volume of liquid may be less,
leaching fields or other soil adsorption systems receiving such wastes
should be conventionally designed and not otherwise reduced in  size  if
BOD loading is unchanged.  Tank size for other forms of  "packaged"
treatment for such wastes may be reduced but the energy  and/or  chemical
requirements will be higher because of higher concentrations of
pollutants.
         Vault toilets are best suited for seasonal use, particularly in
the summer.  They are most widely used at camps and recreational  sites.
There can be problems in these cases because of indiscriminant  dumping  of
trash and garbage which increases the clean-out frequency.  In  any  event,
periodic cleaning and disposal of vault wastes is required.  Basic  design
is similar to conventional practice.
         Appendix B describes various types of household water
conservation alternatives, including toilet systems.  Recirculating
chemical toilets are in common use in airplanes and travel trailers.
Capital costs are high ($100-$1000) and chemicals are expensive.  The
mechanisms are complex, maintenance is required, and periodic disposal  of
collected material is still necessary.
         Variations include single-pass or reeyole  toilets which  use a
fluid other than water.  Fuel oil has been tried on a single-pass basis
with the entire mixture then burned for heat.  The  fire hazard  at the
toilet was considered significant.  An alternative  ia to mix  the  waste
from low water use toilets with fuel oil  for burning in boilers.   Either
approach requires complex equipment and skilled maintenance.  Recycle
toilets based on mineral oil are available.  The specific  gravities are
sufficiently different  that the oil and waste  separate  in  a holding tank
and the oil is recycled.  Disposal of the colleeted wastes is  still required
and costs for a  single  unit may approach  several thousand  dollars.
         Ineinerating toilets, whether based on oil, gas or electricity,
require considerable energy, are complex  to maintain, and  can  be

-------
                                  9-33
 aesthetically  objectionable,  particularly  where  a temperature inversion
 exists  and  vent  stack emissions  sink rather  than rise.
          Composting  toilets are  in  wide  use  in Scandanavia for vacation
 homes.   A full-scale  unit  can receive all  feces, urine,  and kitchen
 wastes  from a  household.   Wash water and other liquids must be discharged
 elsewhere.   Successful operation  requires  a  degree of commitment and
 dedication  not commonly found in  the North American Arctic and subarctic.
          The most  common nonwater carriage system in use is the honey bag
 toilet.   Pickup, handling  and disposal of  the bags creates potential
 health  problems.   Efficient systems  of this  type are in  operation in
 coastal  communities in Greenland, where  pickup and disposal is a reliable
 municipal service.   Section 13 discusses ultimate disposal.
 9.6       Operation and Maintenance
          Repeated  studies  of  treatment systems in cold climates have
 shown that  performance does not achieve  the  design goals due to poor
 operation and maintenance.  Initial  operator training is essential  to
 successful  system  performance.  Another  critical element in the design
 process  for wastewater treatment  is  the  preparation of the operations and
maintenance manual.   It is even more important in the arctic and
 subarctic because  of  the remote locations, the general lack of skilled
 personnel,  and the relatively rapid  turn-over of operators at both
military  and civilian  treatment systems.   In the former  case, a one-year
 tour of duty is normal.  This lack of continuity and experience results
 in a situation where  the operator's  only routine source  of guidance and
assistance  is the manual.  Minor  details which may appear  self-evident to
 the designer/author may be critical  to the operater/reader.
 9.6.1     Contents of O&M manuals
         The basic requirements for  process  operation and  maintenance may
not differ  from eonventional  temperate zone  practice but  the  cold regions
O&M manual  should explain them in greater  detail  since it  may be the  only
information source.  Special  winter  operational  requirements  must be
clearly defined.  These may include  draining lines, winterizing  pumps,
activating heat tapes, etc.   Equipment for emergency or  future  use  must
be clearly identified.  For example, a heat  tape  intended  to  thaw a pipe

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                                 9-34
need not be continuously operated, and extra pumps and blowers may only
be for standby.
9.6.2    Design for O&M
         Attention to detail during design of a system will help relieve
or avoid subsequent operational or maintenance problems.  Many typical
examples, such as condensation and control panel locations, were
discussed previously in this chapter as they relate  to a  particular
process design.  Other generally applicable items would include:
         a)  Alarm systems  to indicate failure in the process (i.e.,
             power failure, overflow, etc.) are essential, particularly
             for small units that receive  intermittent attention.
         b)  The air circulation and heat  distribution in an enclosing
             structure must be carefully planned.  Often  the temperature
             at the floor level and in "blind" spots can  be below
             freezing, resulting in freezing of pipes and appurtenances.
         c)  The depth and  location of winter  ice and snow cover must be
             considered to  ensure easy access  to all critical  components.
         d)  Pumps and other intermittently used facilities must either
             be protected or winterized each year.
         e)  Coordination must be established  with other  critical
             elements in  the community or  camp to avoid unexpected  or
             adverse effects on  the system.  Dumps or spills of  toxic
             materials must be controlled. An improperly maintained  or
             located grease trap could  freeze  or  impose excessive  organic
             loads on a  system.
         f)  Some  remote  systems may  be  subject  to  power  failures  and
             voltage variations.   Provisions  should  be made  to  protect
             electrical  equipment  from  burning out due  to low  voltage.
 9.7      Costs
         There are no  simple  rules  of  thumb for  estimating  costs of cold
 regions  waste  treatment  systems  because  of the limited  data  base,  the
 extreme  variability  of  logistical  problems,  and  high labour  rates.  Most
 temperate  zone cost  data  do not  include  the small-scale  systems commonly
 required in the Arctic.   The  selection of  appropriate  indices  and trend

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                                  9-35
factors can also be a problem; extrapolation  from  temperate  zone values
is not recommended except for large communities.   Two  sources  of cost
data for waste treatment in Alaska were available.  The  first  compares
construction costs for facilities at the Alaska pipeline camps and  is
summarized on Table 9-9.  The other is from a series of  partial-mix
aerated lagoons constructed by the U.S. Army  Corps of  Engineers, Alaska
District, in 1972 at various locations in Alaska.  These data  are
summarized on Tables 9-12 through 9-15.
         Anchorage, Ak, was adopted as the base and the  individual  costs
from remote sites were used to generate the relative cost factors shown
on Table 9-13.  This gives an approximation of the variation in costs due
to location.
         Construction costs for a large (3800 m^/d) partial-mix
aerated lagoon near Fairbanks, Ak, are summarized  in Table 9-14.
Estimated O&M costs for smaller lagoons are given  in Table 9-15.
   TABLE 9-12.  CONSTRUCTION COSTS - PARTIAL-MIX AERATED LAGOONS (1972 $)
   All single-cell, membrane-lined, including control  building with blowers
   and erosion chlorinators.  Size range:  10 000  - 14 000 gpd (38-53
   nr/d)   Cost values are the average of six installations* and are
   expressed in dollars per 1000 gal (3.785 m3) of average daily flow.
            Lagoon
              Materials and equipment                $3 400
              Labour                                  2 900
                                                     $6 300
            Control Building
              Materials and equipment                $1 600
              Labour                                  1 100
                                                     $2 700
            Actual Construction                       9 000
            Mobilization and Demobilization (15%)     1 400
            Design, Inspection, Misc. (13%)           1 200
                                      Total Cost    $11 600

            * Locations:  Tin City, Cape Lisburn, Tatalina, Indian
                          Romanzof, Cape Newenham (Alaska).

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                                  9-36
TABLE 9-13.  RELATIVE COST FACTORS - PARTIAL-MIX AERATED LAGOONS (1972 $)

All single-cell, membrane-lined, including control building with blowers
and chlorination.  Size range:  10 000 - 30 000 gpd (38-114 m3/d).
Based on total costs including all construction, mobilization demobilization,
design and inspection.  Costs expressed as an index relative to Anchorage.

             Location	Cost Factor
             Anchorage                                   1
             Cape Romanzof                              3.3
             Cape Newenham                              3.6
             Indian Mountain                             4
             Cape Lisburne                              4.3
             Tin City                                   4.6
TABLE 9-14.  CONSTRUCTION COSTS - EIELSON AFB AERATED LAGOON (1972 $)
        o
A 3800 mj/d, two-eel! lagoon, lined with butyl rubber membrane.
Helical aeration diffusers, 28 m  control building with blowers,
and a chlorine contact chamber.


 Lagoon

   Materials and Equipment                          $280 000
   Labour                                            108 OOP
                                                    $388 000

 Control Building
   Materials and Equipment                            81 000
   Labour                                             47 OOP
                                                    $128 OOP
 Actual Construction                                $516 PPP
 Mobilization and Demobilization (9%)                 46 000
 Design, Inspection, Misc. (13%)                      73 OOP

                                     Total Cost     $635 OOP
 Cost by engineering discipline:

   Civil Engineering                                45%
   Mechanical Engineering                           50%
   Electrical Engineering                            5%

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                                  9-37
    TABLE 9-15.
ESTIMATED ANNUAL OPERATION AND MAINTENANCE COSTS
PARTIAL-MIX AERATED LAGOONS IN ALASKA (1972 $)
                                  Labour
                                       Materials
Elendorf AFB
11 m3/d
sigle-cell

Widwood, AFS
60m3/d
tw-oell

Kig Salmon AFB
30m3/d
sigle-eell
                 $4 000
                 $2 200
                 $7 300
$1 000
$1 000
$4 000
The influence of remote location is apparent when the values  for

Elmendorf AFB, in Anchorage, are compared to those for King Salmon AFB,

which is on the Alaska Peninsula.

9.8      References

1.   Bailey, J.R.  et al, A study of flow reduction and treatment of
        wastewaters from households.  U.S.  Federal Water Pollution
        Control Administration, Contract Report 14-12-428, 1969.

2.   Witt, M.D. et al, Rural household waste eharaeterization.
        Proceedings of the National Home Sewage Disposal Symposium, ASAE
        pubs., Proo. 175, 1974.

3.   Jespersen, F., The vacuum sewage system.  Utilities Delivery in
        Arctic Regions.  D.W. Smith (ed.), Environment Canada Rpt. EPS
        3-WP-77-1, pp. 364-387, Ottawa, 1977.

4.   Given, P.W. and H.G. Chambers, Workeamp sewage disposal.  Some
        problems of solid and liquid waste disposal in the northern
        environment, Environment Canada Rpt. EPS-4-NW-76-2, pp. 1-42,
        Edmonton, 1976.

5.   Flaek, J.E., Design of water and wastewater systems for rapid growth
        areas.  Environmental Resources Center, Colorado State University
        Press, 149 pp, 1976.

6.   Snoeyink, V.L. et al.  USAF Mobility Program Wastewater Treatment
        System, U.S. Air Force Teeh. Rpt. AFWL-TR-71-169,  60 pp, 1972.

7.   U.S.  Environmental Protection Agency, Process design manual for
        wastewater treatment faeilities in sewered small communities,
        EPA-625/1-77-009,  1977.

-------
                                 9-38
9.9      Bibliography

     Alter, A.J.  Sewage and sewage disposal in cold regions.  U.S.
     Army, Cold Regions Research and Engineering Laboratory.  Monograph
     III-C5b, 106 pp, 1969.

     Alter, A.J.  Water supply and waste disposal concepts applicable in
     permafrost regions.  Proceedings of the 2nd International Permafrost
     Conference, Yakutsk.  North American Contribution.  Academy of
     Sciences, National Research Council, pp. 557-581, 1973.

     Alter, A.J.  The polar palace.  The Northern Engineer, University of
     Alaska, 5:2, 4-10, 1973.

     Antonie, R.L.  Rotating biological contactors for secondary waste-
     water treatment.  Lake Tahoe Wastewater Treatment Seminar Manual,
     1976.

     Benjes, H.H., Small community wastewater treatment facilities -
     biological treatment systems.  Design Seminar Handout, Small
     Wastewater Treatment Facilities, U.S. Environmental Protection
     Agency, Cincinnati, Ohio 1978.

     Buens, G.E., Evaluation of aerated lagoons in a cold climate.
     Proceedings 22nd meeting Western Canada Water and Sewage Conference,
     pp. 21-40, 1970.

     Christiansen, C., Cold climate aerated lagoons.  Proceedings 2nd
     Int. Symp. on Cold Regions Engineering. J. Bwolich and P. Johnson
     (ed.), University of Alaska, Fairbanks, pp.  318-351, 1977.

     Clark, S.E. et al, Biological waste treatment in the far north.
     U.S. Environmental Protection Agency (FWQA), Project Report 1610, 36
     pp, 1970.

     Clark, S. et al, Alaskan industry experience in arctic sewage
     treatment.  Working paper No. 13 at 26th Purdue Industrial Waste
     Conf., Purdue Univ, Lafayette, Indiana, 1971.

     Clark, S., Coutts, H., and Christiansen, C., Design considerations
     for extended aeration in Alaska.  Murphy, R. and Nyquist, D. (ed.),
     Water Pollution Control in Cold Climates, U.S. Environmental
     Protection Agency, Water Pollution Control Research Series 16100 EXH
     11/71.  pp. 213-236, 1971.

     Clark, S.E. et al, Alaska Sewage Lagoons.  2nd Intl. Symp. on Waste
     Treatment Lagoons, U.S. Federal Water Quality Administration,
     Washington, B.C., pp. 221-230, 1970.

     Coutts, H., Arctic Evaluation of a small physical-chemical sewage
     treatment plant.  U.S. Environmental Protection Agency, Arctic
     Environmental Research Lab., Fairbanks, Alaska, 1972.

-------
                            9-39
Eckenfelder, W.W. and A.J. England, Temperature effects on
biological waste treatment processes.  Symposium on Water Pollution
Control in Cold Climates, R.S. Murphy and 0. Nyquist (ed.),
University of Alaska, Fairbanks, pp. 180-190, 1970.

Gordon, R. and Davenport, C., Bateh disinfection of treated
wastewater with chlorine at less than 1C.  U.S. Environmental
Protection Agency, Washington, B.C., EPA-660/2-73-005, 1973.

Grainge, J.W. et al, Management of waste from arotie and subarctic
work camps, report for Task Force on Northern Oil Development.
Report 73-19, Information Canada Cat. No. R72-10173, 153 pp, 1973.

Grainge, J., Impact of community planning on quality of life in the
north.  Proceedings of Third National Hydrotechnical Conference,
Quebec, pp. 483-500, 1977.

Grainge, J.W., Shaw, J.Q. and Slupsky, J.W., Report on Toilet Units.
Public Health Engineering Div., Dept. of Environment, Edmonton,
Alberta.  Manuscript Report NR-71-2.  21 pp, 1971.

Grube, G. and Murphy R., Oxidation ditch works well in subarctic
climate.  Water and Sewage Works, Vol. 116, No. 7, pp.  267-271,
1969.

Heinke, G.W. and D. Prasad, Disposal of concentrated wastes in
northern areas, Environment Canada Report EPS 4-NW-76-2, pp.
87-140, Edmonton, 1976.

Rickey, J. and Duncan, D., Performance of single family septic tank
system in Alaska.  JWPCF 38:  1298-1309, 1966.

LeGros, P.G., and N.L. Drobny, Viruses in polar sanitation - a
literature review.  U.S. Navy, Civil Engr. Lab. Tech Rpt. R-505, 15
pp, 1966.

Lin, K.C. and G.W. Heinke.  Plant data analysis of temperature
significance in the activated sludge process.  JWPCF, 49(2):286-295.

Metcalf and Eddy Inc.  Wastewater Engineering:  Treatment, Disposal,
Reuse.  McGraw-Hill Book  Co., New York, 920 pp, 1979.

Middlebrooks, E.J., C.D. Perman and  I.S. Dunn, Wastewater stabiliza-
tion lagoon linings, U.S. Army Cold  Regions Research and Engineering
Laboratory, Special Report, in press, 70 pp, 1978.

Morrison, S.M. et al, Lime disinfection of sewage bacteria at low
temperature.  U.S. Environmental Protection Agency.  EPA 660/2-73-
017, Washington, D.C., 90 pp., 1973.

-------
                            9-40
Murphy, R. and Ranganathan, K., Bio-processes of the oxidation ditch
in a sub-arctie climate.  IN:  Davis, E. (ed) , International
Symposium on Wastewater Treatment in Cold Climates, Environment
Canada Report EPS 3-WP-74-3, Ottawa, 1974.

Murphy, R.S., et al, Water supply and wastewater treatment at
alaskan construction camps.  U.S. Army  Cold Regions Research and
Engineering Laboratyr, Report in press, 1978.

Orr, R.C. and D.W.  Smith.  A review of  self-contained toilet systems
with emphasis on recent developments.   Utilities Delivery in Arctic
Regions.  D.W. Smith (ed.).  Environment Canada Rpt. EPS 3-WP-77-1,
pp. 266-308, Ottawa, 1977.

Otis, R.J., et al.  On-site disposal of small wastewater flows.
U.S. Environmental  Protection Agency, Washington, D.C.,
EPA-625/4-77-011, 1977.

Puchtler, B., Reid, B., and Christiansen C., Water-related utilities
for small communities  in rural Alaska.  U.S.  Environmental Protec-
tion Agency, Washington, D.C., EPA-600/3-76-104, 1976.

Reed, S.C. and R. S. Murphy, Low temperature activated sludge
settling.  Journal  S.E.D.  ASCE, SA4, 747-767, 1969.

Reed, S.C., Alternatives for upgrading  USAF wastewater  lagoons in
alaska.  U.S. Army  Cold Regions Research and  Engineering Laboratory,
Hanover, New Hampshire, 94 pp., 1976.

Reed, S.C. et al, Land treatment of wastewater for Alaska.
Proceedings Second  International Symposium  on Cold Regions
Engineering, J.  Bordiek and P. Johnson  (ed.), Univ. of  Alaska,
Fairbanks, pp.   316-318, 1977.

Reid, B.H., Some technical aspects of the Alaska village
demonstration project. IN:  Utilities  Delivery in Arctic Regions,
Enviro-nment Canada  Rpt.  EPS 3-WP-77-1, pp.   391-438, Ottawa,1977.

Reid, L.C. Jr.,  Design and operation of aerated lagoons for  the
arctic  and subarctic.  Presented at  the U.S.  EPA Technology  Transfer
Design  Seminar,  Anchorage, Ak., April 9-10, 1975,  29 pp, 1975.

Ryan, W., Design and  construction of practical  sanitation  facilities
for small Alaskan villages.  Permafrost.  Proa, of the  2nd
International Conference, Yakutsk.   North American Contribution.
National Academy of Sciences, National  Research Council, pp.
721-730, 1973.

Sletten,  R.S., Land application of wastewater in  permafrost  areas.
3rd International  Permafrost Conference,  National  Academy  of
Science,  Washington,  D.C., 1978.

-------
                             9-41
Smith, D.W. and P.W. Given, Evaluation of northern extended aeration
sewage treatment plants.  Proceedings 2nd International Symposium on
Cold Regions Engineering, J. Burdick and P. Johnson (ed.)> Univ.  of
Alaska, Fairbanks, pp.  291-316, 1977.

Tilsworth, T. et al.  Freeze conditioning of waste activated sludge.
Proceedings 27th Industrial Waste Conference.  Purdue University,
486-491, 1972.

U.S. Army.  Domestic wastewater treatment TM 5-814-3, in press.
U.S. Army Corps of Engineers, Wash. D.C., 1978.

U.S. Environmental Protection Agency, Process design manual for land
treatment of municipal wastewater, EPA 625/1-77-008, Washington,
D.C., 1977.

U.S. Navy.  Design Manual, Cold Regions Engineering, NAVFAC DM-9.
Dept. of Navy, Naval Facilities Engineering Command.  Alexandria,
Va., 1975.

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                                 SECTION 10
                            WASTEWATER DISPOSAL
                                  Index
                                                                    Page
10       WASTEWATER DISPOSAL                                        10-1
10.1     Discharge Standards                                        10-1
10.1.1   Environmental conditions                                   10-1
10.1.2   Standards                                                  10-3
10.1.3   Microbiological considerations                             10-4
10.2     Subsurface Land Disposal                                   10-4
10.2.1   Septic systems                                             10-5
10.2.2   Mechanical systems                                         10-9
10.2.3   Seepage pits                                               10-9
10.3     Outfalls                                                   10-9
10.3.1   Receiving water                                            10-10
10.3.2   Types of outfalls                                          10-11
10.4     Intermittment Discharge                                    10-12
10.4.1   Thermal considerations                                     10-12
10.4.2   Seasonal discharge                                         10-14
10.5     Land Disposal                                              10-15
10.5.1   Soil conditions                                            10-15
10.5.2   Annual cycle                                               10-15
10.5.3   Loading rates                                              10-15
10.6     Swamp Discharge                                            10-16
10.6.1   Area affected                                              10-16
10.6.2   Management                                                 10-18
10.6.3   Effects                                                    10-18
10.7     Sludge Disposal                                            10-18
10.7.1   Sludge drying/freezing                                     10-19
10.7.2   Sludge pits                                                10-19
10.7.3   Lagoon sludge disposal                                     10-20
10.7.4   Landfill                                                   10-20
10.8     References                                                 10-20

-------
                             List of Figures
Figure
10-1
10-2
10-3
10-4
10-5
Soil Profiles
Insulation in Soil Adsorption Fields
Maximum Ice Thiekness Observations, 1969-70
Example of an Ocean Outfall Design
Lagoon Weir Design
                                                           Page
10-6
10-8
10-10
10-12
10-13
10-2
10-3
                               LIST OF TABLES
Winter Dissolved Oxygen Concentrations in Selected
Streams
Efficiency of Septic Tanks
Results of Spray Application of Lagoon Effluent at
Eielson Air Force Base (15 em lysimeters)
Page

10-2
10-5

10-17

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                                 10-1
10       WASTEWATER DISPOSAL
10.1     Discharge Standards
         A total water management program requires the return of the
water to the environment.  The treatment requirements in northern loca-
tions must normally be based on winter receiving water characteristics,
which include critically low flows and dissolved oxygen levels.  Two
general approaches used to control man-created wastewaters are:
         1)  basic effluent standards, and
         2)  specific stream standards.
         Most North American locations make use of a combination of the
two types of standards.  The important aspects of the two approaches  to
water management are presented below.  Details of subsurface disposal,
outfalls, intermittent discharges, land disposal, swamp discharge and
sludge disposal follow the discussion of standards.
10.1.1   Environmental conditions
         Present knowledge of how arctic and  subarctic river, lake and
estuary systems respond to wastewater discharges is limited.  Some basic
information on the physical and chemical conditions, and the ecology  of
streams and rivers has been gathered.  The annual cycles in  subarctic
lakes are just now becoming subjects of more  interest and study  [1,2].
Not only is information on how aquatic systems function limited, but  the
situation is compounded by extremely varied conditions throughout the
North.
         The environmental conditions within  northern rivers and lakes
vary considerably with time of year and location.  Winter flow in many
rivers is negligible, while summer flows may  be high and carry heavy
sediment loads.  Ice cover is the rule, rather than the exception, with
water temperatures at 0C in the winter, and  generally low during the
remainder of the year.  During periods of iee cover, the concentration of
dissolved oxygen (DO) progressively reduces.  Near the mouths of most
major rivers in Alaska, natural winter DO levels are well below generally
recommended minimums, as shown in Table 10-1  [3],  The organisms present
have adapted to these harsh conditions through such methods  as reduced
metabolic rates and migration.  However, tolerance levels have not been
well defined.

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                                 10-2
  TABLE 10.1  WINTER DISSOLVED OXYGEN CONCENTRATIONS IN SELECTED STREAMS
Stream/Location
Yukon River
near Eagle, Ak (1664 km upstream)
near Alakanuk, Ak
Tanana River
near Fairbanks
at Yukon River
near Fairbanks
at Yukon River
Colville River
at Umiat
Kuparuk
Dissolved
Oxygen
mg/L

10.5
1.9

9.9
5.7
10.8
6.5

7.5
8.4
8.4
Date of
% saturation Sample

73
13

69
40
75
46

52
58
58

Mar. 1971

23 Feb. 1970

5 Mar. 1970


Mar. 1969
Mar. 1969
Feb. 1971
Based on Reference [3],
         Few studies of the effects of wastewater discharges on these
waters have been conducted.  Gordon [4] showed in laboratory experiments
that indigenous bacteria exerted an oxygen demand at low temperatures,
and the addition of organic and inorganic nutrients increased the rate of
oxygen utilization.  Murray and Murphy [5] also studied the biodegrada-
tion of organic substrates at low temperatures.  They found that the
food-to-microorgandsms (F/M) ratio was more important than temperature in
determining the rate of DO depletion.
         In another study, the effect of ice cover on the DO content of
the Red Deer River in Alberta was measured [6],  In this river, which
receives municipal effluent, the initial five-day, 20C biochemical
oxygen demand  (BOD) of the river below the outfall and the rate constants
established by BOD bottle tests were found to bear little relation to
oxygen uptake  in the ice-covered, shallow river.  Total organic carbon
(TOC) was closely related to oxygen depletion.  It was concluded that
biological oxidation under river ice was a complex reaction and the bottom
characteristics and benthic demand were very important.  The bottom of

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                                  10-3
Red Deer River  is mainly  gravel  and  rock,  allowing  a large  surface area
for the growth  of microorganisms.
         In  evaluating  the  effect  of wastewater  discharges  from construc-
tion camps,  Greenwood and Murphy [7]  estimated  that a 300-man  camp
located near the mouth  of the  Colville River, Alaska, could store
wastewater for  nine months, discharge it during  a one-month period in
June, and increase the  stream  BOD  by only  0.0026 mg/L with  proper
dilution.  This approach, the  use  of dilution,  is a very real  alternative
which warrants  careful  consideration.
         The results of many of  the  studies and  evaluations differ but
are not necessarily contradictory, because each  study was conducted under
different conditions.   There are many gaps in the knowledge of aquatic
kinetics yet to be filled before the assimilative capabilities of a
northern receiving water  can be  accurately assessed or predicted.
         Assimilative capacities of  northern rivers in the  winter are
undoubtably  lower, and  perhaps much  lower, than  rivers of similar
physical characteristics  located in  temperate zones.   Considering the
complexity of the ecosystem, the great range of  physical characteristics,
and the impossibility of  comparing these rivers  to  those in areas where
much more research and  experience  has been documented, it will be quite
some time before northern water  systems can be accurately modelled.
Oxygen utilization rates  and reaeration coefficients  at temperatures near
0C need further development.  In  the interim, the  aquatic  integrity
must be protected by knowledgeable utilization of the limited  data
coupled with common sense.
10.1.2   Standards
         Standards to protect  the  ecological, aesthetic and sanitary
integrity of  receiving  waters ean  be  divided into three types  [8]:
         1)   standards  based solely  on receiving water quality,
         2)   standards  based on  the  quality of the  effluent discharge,
         3)   standards  which combine  both of the above.
         Physical, ecologieal, and assimilative  capacity characteristics
of receiving waters vary  considerably, as do land use  and population
density.  These variations, together with the economic limitations  and

-------
                                 10-4
social structure, make standards based on a combination of receiving
water quality and effluent discharges appear the most reasonable.
         The interim guidelines for wastewater treatment for the Yukon
and Northwest Territories were established on a community-by-community
basis [12],  Decisions on treatment recommendations were based on
comprehensive studies of expert opinion on public health and environ-
mental needs.  Of course, they are subject to modification as community
conditions or environmental requirements change or as more information
becomes available.  Exact treatment techniques were not specified;
rather, general effluent quality objectives were established.  This
appears to be a sound approach to meeting the environmental quality needs
of the North.
         Presently, the State of Alaska and the U.S. Environmental
Protection Agency require mandatory secondary treatment, with further
treatment of the wastewater required if it is to be discharged to
sensitive receiving waters.  These standards were established on a
nationwide basis.   Contact should be made with the appropriate
territorial water board, provincial government agency, federal government
agency or, in Alaska, the Department of Environmental Conservation, to
establish the required quality for discharge to available receiving
waters.
10.1.3   Microbiological considerations
         The survival of pollution indicator microorganisms has been
shown to be longer  in cold water than in warm.  Gordon [9], Davenport et
al  [10] and Bell et^ ja_l  [11] have pres.ented detailed information on  the
extended survival of these organisms in northern rivers.  This informa-
tion  identifies the need for careful consideration of disinfection  to
ensure that water uses are not seriously affected.
10.2     Subsurface Land Disposal
         Several methods of wastewater disposal into  soil are or  have
been  practiced, including absorption field disposal of septic  tank  or
aerobic treatment effluents, direct burial in  pits, disposal  in  ice
crypts or  snow  sumps, and dumping  and covering  in a landfill.

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                                 10-5
10.2.1   Septic systems
         Septic systems can be used in some arctic and subarctic
locations.  The presence of, and depth and thickness of permafrost, the
type of soil and its percolation rates, and the frost penetration depth
will influence the use of septic systems.  General septic system design
information is available from several sources, such as the "Manual of
Septic Tank Practice" [13], and the "Private Sewage Disposal Systems
Instructions to Installers, 1978"  [14].
         The basic functions of septic tanks are:  a) removal  of
settleable and flotable solids, b) sludge and scour storage, e) some
anaerobic biological treatment, and d) to condition liquids  for ground
adsorption (hydrolyze solids).
         Some efficiency information for septic tanks used in  cold climate
regions are presented in Table 10-2.
                 TABLE 10-2.  EFFICIENCY OF SEPTIC TANKS
                                       Percent       Removal
Conditions	BOD	SS    Total Solids  References
Average of 10 Air Force Base sites  33     42         22            [15]
 in Alaska
Tanks in heated houses              46     64         48            [15]
Tanks - steam heated                40     31         34            [15]
Tanks - unheated                    14     38         30            [15]
Field study at College, Alaska,
 2.5-day detention  time             28     43         -             [16]
Lab study, U.S. PHS, temperature
 4-10C, 2-day detention  time       49-52  83-89      31-41        [17,18]
Lab study, University of  Washington,
 temperature 4.4 and 15C,  4.5-day
 detention time                     49-52  83-86      31           [17,18]
Normal primary sedimentation        20-40  45-70                   [17,18]

         The sizing of the  system should follow procedures in the
"Manual of Septic Tanks Practice" [13].

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                                             10-6
          10.2.1.1  Soil conditions.   The most critical  aspect of arctic and sub-
          arctic septic systems design is the soil  condition.  Figure 10-1 shows
          examples  of  soil profiles  found in subarctic  areas of Alaska.  The type
          of soil will influence  the frost penetration  depth.  Its  location with
          respect to  surface and  groundwater will also  influence frost penetration
          and frost heave.  In locations where permafrost is deep  it  may be possi-
          ble to install an absorption field.  However, groundwater (suprapermafrost
          water) movement patterns  should be investigated, along with potential
          groundwater  supply locations.   Percolated  water from the  absorption  field
          may move  down to the frozen soils and  then tend to move  horizontally.
          Depending upon the total  temperature regime,  the wastewater may cause
          additional  thaw of the  permafrost.
                    Thermal protection for the tank  and  adsorption  field should be
          designed  for the worst  winter  conditions,  minimum or no  snow, and low
 Boring number
   Date drilled
  Water tables
After boring
While drilling
 Frozen ground
Sample location
                                   Typical Boring Log
                                          Elev. 108m
                                                         0
                                                         0.5m
      Organic material	
    Consid Visible Ice  ICE + ML
         106-SJ It estimate 65% Visible Ice
1)280, 56.2%, 1200 kg./m3, ML
                           2.0m
                                       Sandy silt
                               Little to No Visible Ice  4.3-10.0m  0-2 Om Vx 
                                 220,57.1%, 1300 kg./m3,-2, GP,
                                       Sandy gravel
                                                         8.0m
                                 300
                                          Schist
                          10.0m
                                        Elevation
                                        Strata change
                                        Approximate strata change
                                        Ice, description and classification
                                           (Corps of Engineers method)
                                        Unified or FFA classification
                                        Temperature C
                                        Dry density
                                        Water content
                                        Blows/m
                                        Sample number
                                        Drill depth
                                                                       Generalized soil or rock description
                                   FIGURE 10-1.   SOIL PROFILES

-------
                                 10-7
temperatures.  Freezing prevention should be designed  into  the  system.
Year-round operation will require continuous heat additions  in  the  form
of warm wastewater or external heating inputs.  Methods of  preventing
freezing which have been used include:
         1)  housing the septic tank in a warm structure above  or below
             ground;
         2)  placing a steam line along pipes or around septic  tank;
         3)  placing an electric heat tape along pipes or around septie
             tank;
         4)  applying insulation around septic tank and over top of pipes
             (foam, sheets, snow cover, earth cover, etc);
         5)  use of warm water to increase the heat input of wastewater.
         In locations where the need  for wastewater disposal is seasonal,
such as in recreational areas, the tank may be pumped  out after the
recreational activities have ceased.  A minimum of one week between the
cessation of flow and pumping should be allowed.  When the  facilities
remain in operation year-round, but at a reduced flow  during the winter
months, more than one system may be used in parallel to allow part  of  the
unit to be shut down and pumped.
10.2.1.2 Absorption field design.  The soil absorption system serves as
an additional sewage treatment unit.  This component is a subsurface
distribution system which delivers the settled sewage  flowing from  a
septie tank to the soil found suitable for ultimate disposal.  A soil
absorption system may be one of three different types: absorption
trenches, mound seepage beds, and seepage pits.  The absorption trench
system provides the advantage of discharging the settled  sewage near the
surface of the ground and over a wide area.  The seepage  pit, in
comparison, discharges into deeper soil strata at concentrated  points.
         Heat loss control is the key consideration in eold climate
systems.  Figure 10-2 shows how insulation can be used to reduce heat
loss during winter periods.  It should be noted that the  freezing  front
will move down between trenches and may cause the formation of  a finite
thawed area.

-------
                                     10-8
             Top view
                o - }:.'
100 mm Polystyrene 'VTv -V <>--0-
                       '


lank

i
	 1
	 1

1 [
I 	 1
...
:
1 "
L.-..J
1 	 1
i
i r
i 	 1

i i
                               n    n 1000 Drain
                                            Detail
                                               Minimum 2 m
                                                      J_
                                                             0-::-f*-j- Native backfill
                                                                'b 
                                                                   Drain lateral
                              Screened gravel
                                                            1 00 mm Polystyrene
                                                            1 00 mm Drain manifold (header)
Building
                                     Septic tank
                                                         See detail
               FIGURE 10-2.  INSULATION IN SOIL ABSORPTION FIELDS
    10.2.1.3  Dosing tank techniques.  When the quantity  of sewage exceeds the
    amount  that can be discharged in approximately  150 linear metres of absorp-
    tion  field tile, a dosing tank should be used.   Suah a tank allows proper
    distribution of wastewater to different parts of the field.  This technique
    also  allows the absorption field a period of time to percolate the water.
             In cold climates a small continuous discharge may freeze due to
    rapid heat loss to the soil.  In this case., a dosing tank allows a larger
    volume  and a greater amount of heat to be discharged at one time.  This
    provides  for greater penetration of the absorption field.  In some locations
    it may  be desirable to pump the effluent to a suitable absorption area.
             The dosing tank should be equipped with an  automatic siphon whieh
    discharges the tank once every three or four hours.   The tank should have
    a capacity equal to about 60 to 75 percent of the interior capacity of
    the tile  to be dosed at one time.  (See Section 7.)
    10.2.1.4  Clean-out requirements.  Due to the normally low temperatures
    during  all or part of the year, sludge digestion and hydrolization rates

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                                 10-9
will be low and sludge accumulation higher than in  temperate  climates.
This condition results in a more frequent need to remove  sludge  from  the
tank.  Sludge removal frequency should be every 12  to 24  months  in Alaska
and northern Canada.
10.2.2   Mechanical systems
         Several mechanical treatment systems are available  for  small and
moderate quantities of wastewater.  These are discussed in Section 9.
Subsurface disposal of effluent from such plants requires special
consideration.
10.2.2.1 Soil conditions.  The most critical aspect of aerobic effluent
disposal is the solids loading.  Aerobic systems frequently  have excessive
suspended solids concentrations in the effluent.  These systems  should,
therefore, include positive solids separation.
10.2.2.2 Absorption field design.  As with septic systems the key
consideration must be freeze prevention.  With a properly designed solids
separation system clogging of the field will be minimized.
10.2.2.3 Sludge disposal.  To prevent clogging of the absorption field,
sludge must be removed frequently from systems in use in  cold regions.
Disposal practices are discussed in a later section.
10.2.3   Seepage pits
         Deep pits are used in some areas for the disposal of wastewater.
Normally, the area required is fairly large and, therefore,  use  is
limited to a small number of dwellings.  The major  concerns  are  proper
freeze protection and prevention of nitrate and bacterial contamination
of the groundwater.  They are generally much easier to protect from
freezing than an absorption field, and much less excavation  is usually
required.
10.3     Outfalls
         Outfalls to surface water are the most common wastewater discharge
technique.  Design and operation of the discharge systems requires under-
standing of the receiving water quality and quality of the discharge.  It
may be necessary to operate the discharge on an intermittent  or  seasonal
basis.  It is advisable to design the outfall pipe  so that is does not

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                                 10-10
pass through a water-air interface.  This will prevent damage during
periods of ice cover.
10.3.1   Receiving water
         The type of receiving water bodies and the effluent standards
which pertain are important factors in the type of outfall structure
designed.
10.3.1.1 Ponds and lakes.  Ponds are generally shallow, with depths up
                                                                  o
to two metres.  Surface areas range from a few 100 to a few 1000 m  , and
retention times are often extremely long, one to six months.  Freeze depths
may vary from 0.5 to 1.5 m.  Figure 10-3 shows ice thicknesses reported
for different locations.  Ice thickness can be estimated mathematically
by assuming worst conditions of no snow cover and minimum heat input.
         The use of a pond to receive treated wastewater would
effectively convert it to a polishing lagoon.  Fencing and posting  to
that effect is required.  Local regulatory agencies should be consulted
before this approach is adopted.
         FIGURE 10-3.   MAXIMUM ICE THICKNESS OBSERVATIONS, 1969-70
                              (Values in cm )

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                                 10-11
         Lakes may have  the ability  to absorb a greater volume  of
wastewater; however, regional  regulations must be  reviewed.   Important
considerations include surface area, depth, volume-inflow  relationships,
nutrients, flora and fauna, and  benthic  populations.   Effluent  quality,
especially with regard to microorganisms, must be  high if  there is  a
potential for fishery or recreational use of the lake.
10.3.1.2 Streams and rivers.   Northern streams and  rivers  are the most
common receiving waters  for wastewater.  Flow, iee  depth and  movement are
the most important factors to  be considered.  Dissolved oxygen  conditions
through the winter and downstream uses are of particular importance in
selection of the type of outfall structure to be used.
10.3.1.3 Oceans.  Where  possible, ocean  discharge  is desirable.
Normally, the ability to absorb  quality  variations  is  very great.   If
initial dispersion by outfall  design and tidal movement is not  obtained,
however, wastewater will concentrate on  the surface, because  fresh  water
and sewage are less dense than salt water.  The result is  a visible
slick.  The major advantage of sea disposal is dilution.
         The design of the outfall must  consider ice movement due to
tidal action, currents, near-by  rivers and wind action.  Figure 10-4
shows the general design of an ocean outfall for the north eoast.
10.3.2   Types of outfalls
         Three basic types of  outfalls exist:  free fall from a pipe,
submerged diffusers, and weir  structures.
10.3.2.1 Freefall.  Freefall structures  utilize an  insulated  pipe to
transport treated wastewater from the treatment facility to the  discharge
point.  Provisions must be made  for freeze prevention.  Cold  air penetra-
tion into the end of the pipe could create ice blockage of the  line.
10.3.2.2 Submerged pipe.  Unique factors of concern in the design of
submerged outfalls are the problems associated with ice scour,  and  freeze
and iee damage protection of any portion of pipe crossing  the air and
water interface.
10.3.2.3 Weirs.  Weirs develop a number of problems if not properly
designed.  During winter operation the unfrozen effluent must move  to the

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                                  10-12
             Insulated electric heat
                traced outfall pipe
       Wastewater
        discharge
Break-away couplings so that ice
movement may destroy pile
without interruption of service
      Draft control over end of pipe
                              Pile supports
             FIGURE 10-4.  EXAMPLE  OF  AN OCEAN OUTFALL DESIGN
surface where  cooling will occur.   The  effluent is then  discharged to the
surface of  a stream or channel.  Serious icing problems  can  result.
Figure 10-5 shows a design which has  been used successfully.
10.4      Intermittment Discharge
          Winter dissolved oxygen conditions in many streams  will preclude
wastewater  discharge.  In other locations, the volume of effluent may be
so small  as to require slug discharge to prevent freezing.
10.4.1    Thermal considerations
          Due to the location or type  of discharge system used, heat loss
may be so great and the volume so  small, that the effluent  will freeze
before or right at the end of the  discharge line.  The  potential for
freezing  can be determined through the  procedures given  in  Section 15.
Such problems  are most common when freefall systems are  used.  To
eliminate this condition treated effluent should be stored  in a manner
that will prevent freezing, and discharged when sufficient  volume has
accumulated that complete expulsion from the discharge  line is ensured.

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                             Valve box and valve stem extension
                                 Frost heave protection        |Ce cover.
                                                  r-~~-~ 1.5m minimum
      Gate valve -
Gravity outfall
                                                  Upturned elbow
                                                     Anchor block
                   Maximum frost penetration
           Insulated, electric heat traced pipe
                                   2-3
                              Frost heave protection if required
                                        Insulated cover
                                                                          Gate valve
   Concrete pad or rip-rap
                                    -- 40mm
                                          Calking as required
                                               Adjustable stop logs
                                                      Detail
L
                                                                                                                    o
                                                                                                                     I
                                       FIGURE  10-5.   LAGOON WEIR  DESIGN

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                                 10-14
The discharge mechanism could be a syphon or pump, but must ensure that a
trickle discharge does not occur.
10.4.2   Seasonal discharge
         Discharge of wastewater at times of maximum or substantial
stream flow is highly desirable because this eliminates the addition of
oxygen demanding materials to receiving water during the winter period.
The timing of this type of discharge will vary with the location.
10.4.2.1 Flow management lagoons.  Flow management lagoons are used to
control discharge of organios or nutrients to streams or lakes during
periods of concern.  Such systems were used at Trans-Alaska Pipeline camps
to hold wastewater for extended periods through the year.  The holding
lagoons were pumped out during open water periods.  Discharge to the
lagoons was through French drains.
10.4.2.2 Polishing lagoons.  Discharge of treatment facility effluent
to a polishing lagoon may be necessary where the only available receiving
water is sensitive to nutrient additions.  Polishing lagoons provide
additional BOD removal and phosphorus removal by chemical coagulation
during ice-free periods.  Conventional or pumped discharge can be used.
10.4.2.3 Total retention.  Total retention lagoons rely on percolation
and evaporation to dispose of the accumulated water.  Percolation can be
provided by proper selection of the location of the lagoon.  Gravel and
sand gravel areas can be formed in some northern areas.  The lagoon
should be sized to hold an entire winter's wastewater flow (approximately
250 days).  This allows for a particularly severe winter during which the
percolation route is sealed off by freezing.  Discharge facilities also
should be included.
         The water source of the community should be monitored for
contamination if groundwater is used.  The peraolate and groundwater flow
patterns should be studied to ensure that health problems will not oceur.
         Net evaporation can be estimated only roughly from wet and dry
bulb data and precipitation records.  Normally, evaporation is estimated
on the basis of evaporation pan tests and corresponding coefficients;
however, very little data is available in the North.  Care must be taken
in the design to discourage abnormal snow accumulation.

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                                 10-15
10.5     Land Disposal
         Land application of wastewater  requires maintenance  of the  soil
permeability.   In  some cold climate  areas  this may  be  possible  through
special design.  However, many areas are unsuitable.   The  presence of
permafrost will limit vertical movement  of  the wastewater,  and  winter
freezeback of the  active layer may prevent  horizontal  movement.  It  may
be possible to  design a suitable  system  in  areas where thawed zones
extend to a water  body which does not completely freeze.
         Another approach warranting consideration  is  the  use of a
retention-land  disposal system, making use  of land  disposal during the
warmer parts of the year and retention through the  winter.
         In general, land disposal is similar and subject  to  the same
constraints as  land treatment.  The major  difference is that  land
disposal systems are mainly concerned with  getting  the effluent into the
ground and away from the site.  The major  concern is that  the effluent
moves in an acceptable direction  and does not present  a hazard  to public
health.
10.5.1   Soil conditions
         Arctic areas underlain with permafrost generally  will  be limited
to non-infiltration land disposal techniques.  Overland flow  techniques
may be suitable; however, little  or no control studies have been
conducted.  Essential considerations include winter storage requirements.
         Suitable  areas can be located for  infiltration approaches in
areas of disoontinous permafrost.  Again the winter storage requirements
are paramount.  Design details are available in the U.S. Environmental
Protection Agency's "Technology Transfer Design Manual of  Land  Disposal"  [22],
10.5.2   Annual cycle
         Annual cycles involve the management of wastewater in  conjunction
with winter and summer conditions.  Complex installations  may allow  land
disposal of effluent during the summer and  fall, discharge  during early
winter, and ice mounding in late winter.
10.5.3   Loading rates
         As with absorption fields, the  allowable application rate is  a
function of the soil hydraulic capacity.  Methods for  estimating
application rates are given in the "Design Manual of Land  Disposal"  [22].

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                                 10-16
         The effects of untreated wastewater disposal  in cleared  areas
were studied in the Northwest Territories [23].  Only  one  application of
wastewater was made to the test plots.  The soils were identified  as fine
glacio-lacustrine sands with no permafrost at the Fort Simpson  site, and
a 30-cm thick organic layer underlain by high ice content  clayey  till at
the Normal Wells site.  The loading rates varied from  1.3  cm  to 20.3 cm,
and results indicated no apparent adverse effects on the vegetation.
There were indications that pioneer vegetation in disturbed areas  with
low nutrient availability may benefit from sewage irrigation.   Suitable
loading rates were not examined.
         Slow infiltration land application was studied at an interior
Alaska location [24].  The soil, classified as a sandy-silt, was  able to
accept 15.2 cm of secondary lagoon effluent per week for the  summer  test
period.  Performance data is presented in Table 10-3.
10.6     Swamp Discharge
         The use of natural swamps for treating or  polishing wastewater
has received considerable attention in recent years.   Swamp discharge has
been practiced in several places in the North; however, detailed  studies
have been limited.  It is important to design the outfall  diffuser for
maximum dispersion into the swamp.
10.6.1   Area affected
         Discharge of untreated wastewaters to a swamp at  Hay River,
Northwest Territories was investigated in detail by Hartland-Rowe  and
Wright [26].  Assuming no equilibrium, they estimated  that the  effect of
                                                 r\
the effluent could be detected in an area of 35 m  per each man-year
of sewage discharged.  If equilibrium conditions were  assumed after  five
years of operation it was estimated that 110 m^ were ecologically
influenced by each contributing person.
         Higher quality effluents would be expected to influence  less
area.  In a study by Fetter _et Jil. [27] the polishing capability of a
natural marsh of 156 ha with an average depth of 0.5 m was assessed.  The
wastewater flow was approximately 1000 m^ per day, which constituted
about 20 percent of the flow into the marsh.  The discharge was found to
attain the following reductions:

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                                 10-17
      TABLE 10-3.  RESULTS OF SPRAY APPLICATION OF LAGOON EFFLUENT
                   AT EIELSON AIR FORCE BASE (15-cm lysimeters)*

Test
Cell
1974
A


B


C


1975
A


B


C


Application
rate
cm/m/wk

0.75 Mean
Max
Min
1.20 Mean
Max
Min
1 . 7 Mean
Max
Min

Mean
Max
Min
Mean
Max
Min
Mean
Max
Min

TOG
mg/L

22
47
13
25
34
10
23
36
13

-
-
-
_
-

_
-


BOD
mg/L

-
-


-

_
-


3
8
0
11
50
2
5
18
0

SS
mg/L

6
10
3
4
8
2
13
28
5

136
511
11
11
29
4
63
428
7

FC
per 100 ml

-
-

-
-

_
-


802
2 400
0
20 350
102 000
0
7 656
36 000
16
* References [24] and [25].

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                                  10-18
         Parameter	Percent Reduction
         BOD                                       80.1
         Coliform                                  86.2
         Nitrate                                   51.3
         COD                                       43.7
         Turbidity                                 43.5
         Suspended Solids                          29.1
         Total Phosphorus                          13.4
10.6.2   Management
         In general, swamp areas can provide effective  polishing  of
effluent from treatment plants.  If excessive BOD and suspended  solids
are allowed to enter the area, normal aerobic-anerobic  relationships  may
be shifted severely to the anaerobic side.  Such a  condition  could result
in the release of excessive odours and decreased performance  of  the
area.
         The area should be well posted at 50 to 100-metre  intervals.
The signs should identify the area as part of the wastewater  treatment
system.
10.6.3   Effects
         The principal effect of swamp use is that  the  area must  be
assumed to be a part of the treatment system and access limited  or
discouraged.  Depending upon the quality  of the effluent applied  and  the
degree of disinfection, the area will function as a facultative  lagoon.
         The wastewater discharge will increase the number  of pathogenic
bacteria present.  It will also add heat  to the system  during the winter.
         Considerable icing may occur due to the shallow water.   Ice
build-up may retard break-up in the spring.
10.7     Sludge Disposal
         All wastewater management techniques require the disposal of
sludge.  This section presents only those techniques which  make  use  of
unique cold climate conditions.

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                                 10-19
10.7.1   Sludge drying/freezing
         Sludge drying is a common practice at most wastewater  treatment
facilities.  However, very few sludge drying facilities have been
constructed in cold regions.  Sludge dewatering by freezing has  been
investigated by several groups [28].  It was found in one  study  that
application of 10 to 15 cm of sludge during freezing conditions  resulted
in good freeze-assisted coagulation.
10.7.2   Sludge pits
         Sludge disposal pits are one of the most commonly used  methods
of disposal.  Pits can be excavated in almost any material.  Permanent
ice, snow, permafrost, various soils and rock have been used.   Several
years ago, considerable work was done by the U.S. Army Cold Regions
Research and Engineering Laboratory (U.S. ACRREL) on the use of  ice
crypts [29].
         Snow pits were also studied by U.S. ACRREL.  In this case,
sewage diseharged to snow will travel downward, forming a  sump until  it
freezes.  The depth of the sump is dependent on the rate of heat addition
(volume and temperature of the sewage).  The vertical pit will develop
until the percolating liquid freezes to form an impermeable bottom  [30].
         The performance of pits in permafrost or periodically frozen
soil was investigated by Heinke and Prasad [31],  Their recommendation is
presented below:
         "Based on the results of a two year laboratory study, simulating
         a waste pit, it is concluded that it does not provide satisfac-
         tory treatment of human wastes (honey-bags).  The waste pit
         served as a holding tank only at -5C operation.  When  the
         pit was operated at +5C for about three months each year to
         simulate summer conditions, insignificant changes in the values
         of the physical-chemical parameters were observed.  The sole
         significant change was a four-fold increase in the production of
         volatile acids.  A significant increase in the heterotrophio
         bacterial population was observed each year in the latter part
         of +5C operation.  No increase in psyohsophilic bacteria
         was noticed.  Pathogens are likely to remain viable in  the pit
         for many years.
         "Although a waste pit is not a satisfactory treatment method, it
         is considered better than disposal at an open dump or in a
         lagoon, which is designed to receive sewage.  Location of the
         pit is most important.  It should be as far away as practical

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                                 10-20
         from the community and on a site that will not be needed for
         other purposes in the future and which does not drain towards
         water supply sources.  The pit should be sized on the basis of
         20 cu ft per person per year.  For a community of 5000 people, a
         pit of 100 x 25 x 4 ft deep would be required.  A freeboard of 2
         feet should be allowed, the contents to be covered by 2 feet of
         soil when the pit is full and a new one dug.  Where soil condi-
         tions require it, the pit should be lined with heavy plastic
         sheets to prevent seepage through soil to prevent possible
         contamination of ground and surface water.  Truck access for
         easy dumping is required.  A honey-bag disposal station, on the
         Greenland model and as described in the report, could be consi-
         dered together with a waste pit installation.  It would improve
         considerably the solids handling aspect but at a sizeable
         cost."

10.7.3   Lagoon sludge disposal

         Disposal of sludge accumulated in lagoons has seldom been

eonsidered.  Removal of sludge from lagoons is infrequent.  Normal
practice is to move the sludge to a separate holding area, preferably

near the landfill, and cover it with 0.5 to 1.0 metres of soil.

10.7.4   Landfill
         Although landfill dumping of undiluted and treatment plant

sludge is practiced, it is not a recommended procedure without proper

evaluation of the impacts.  Principal considerations are proper  isola-

tion, frequent cover, knowledge of soil conditions and permability,
groundwater depth and direction of movement, and access control  for
people and animals.

10.8     References

1.   LaPerriere, J.D., T. Tilsworth and L.A. Casper, The Nutrient
        Chemistry of a Large, Deep Lake in Subarctic Alaska.  Institute
        of Water Resources Report No. IWR-80, Univ. of Alaska, Fairbanks,
        1977.

2.   Alexander, V., Dynamics of the Nitrogen Cycle  in Lakes.  Institute
        of Marine Science Report Number R71-7, Univ. of Alaska,
        Fairbanks, 1970.

3.   Schallock, E., Low Winter Dissolved Oxygen  in  Some Alaskan  Rivers.
        U.S. Env. Prot. Agency Report No. EPA-660/3-74-008,  Corvallis,
        Oregon,  1974.

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                                 10-21
4.   Gordon, R.C., Depletion of Oxygen by Microorganisms  in Alaskan
        Rivers at Low Temperatures.  IN:  R.S. Murphy, Water  Pollution
        Control in Cold Climates Symposium, U.S. Env. Prot. Agency,
        Washington, D.C., 1970.

5.   Murray, A.P. and R.S. Murphy., The Biodegradation of Organic
        Substrates Under Arctic and Subarctic Conditions.  Institute of
        Waster Resources Report No. IWR 20, Univ. of Alaska,  Fairbanks,
        1972.

6.   Bouthillier, P.H. and K.  Simpson, Oxygen Depletion in Ice Covered
        Rivers.  Jour, of the  Sanit. Eng. Div.. ASCE, 98_, SA2, 341, 1972

7.   Greenwood, J.K. and R.S.  Murphy, Factors Affecting Water management
        on the North Slope of  Alaska.  Institute of Water Resources
        Report No. IWR 19, Univ. of Alaska, Fairbanks, 1972.

8.   Cleary, E.J., Effluent Standards Strategy:  Rejuvenation of an Old
        Game Plan. Jour. Water Poll. Control Fed., 46, 1,9, 1974.

9.   Gordon, R.C., Winter Survival of Feeal Indicator Bacteria in a
        Subarctic Alaskan River.  U.S. Env. Prot. Agency  Report No.
        EPA-R2-72-013, Corvallis, Oregon, 1972.

10.  Davenport, C.V., E.B. Sparrow and R.C. Gordon, Fecal Indicator
        Bacteria Persistence Under Natural Conditions in  an Ice Cover
        River. J. Appl. and Env. Micro., 1977.

11.  Bell, J.B., W. Macrae and J.F.J. Zaal, The Persistence of Bacterial
        Contamination in the North Saskatchewan River in  the Vicinity of
        Edmonton, Alberta.  Environmental Protection Service, Edmonton,
        Alberta, 1977.

12.  Canada. Dept. of Environment.  Interim Guidelines for Wastewater
        Disposal in Northern Canadian.  Water Pollution Control
        Directorate.  Environmental Protection Service, Dept. of the
        Environment, Ottawa, Ontario, 1974.

13.  Anon, Manual of Septic-Tank Practice.  Public Health Service
        Publication no.  526,  Superintendent of Documents, U.S.
        Government Printing Office, Washington, D.C., 1967.

14.  Alberta Labour.  General  Safety Services Division, Plumbing
        Inspection Branch, Private Sewage Disposal Systems Instruction
        to Installers, 1978.  Edmonton, Alberta, 1978.

15.  Straughn, R.O., Septic Tanks at Remote Air Force Installations in
        Alaska.  Environmental Engineering Section, Arctic Health
        Research Center, College, Alaska, 1967.

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                                 10-22
16.  Lamphere, E.M.,  Operation of Experimental Septic Tank Units Under
        Subarctic Conditions.  Proceedings, Third Alaskan Science
        Conference, Sept. 22-27, 1952, Mt. MeKinley National Park.
        Alaska Div. Am. Assoo. for the Advance of Science, Fairbanks,
        1952.

17.  Hindin, E., R.H. Green and G.H. Dunstan, Septic Tank Performance at
        Low Temperatures.  Report No. 27, Div. of Industrial Research,
        Inst. of Technology, Washington State Univ., Pullman, 1962.

18.  Hiekey, J.L.S.,  and D.L. Duncan, Performance of Single Family Septie
        Tank Systems in Alaska.  Jour. Water Pollution Control Federation
        213, 8, 1298,  1966.

19.  Grainge, J.W. and J.J. Cameron, Sewage Lagoons in Northern Regions.
        Presented at the U.S. Environmental Protection Agency Technology
        Transfer Design Seminar, Anchorage, Alaska, 1975.

20.  Reid, L.D., Jr, Design and Operation of Aerated Lagoons for the
        Arctic and Subarctic.  Presented at the U.S. EPA Technology
        Transfer Design Seminar, Anchorage, Alaska, 1975.

21.  Murphy, R.S., G.V. Jones, S.F. Tarlton, Water Supply and Wastewater
        Treatment at Alaskan Construction Camps.  U.S. Army Cold Regions
        Research and Engineering Lab. report in press, Hanover, New
        Hampshire, 1977.

22.  Technology Transfer Design Manual of Land Disposal, U.S. Env. Prot.
        Agency, Washington, D.C., 1977.

23.  Fahlman, R. and R. Edwards, Effects of Land Sewage Disposal on
        Sub-Arctic Vegetation.  IN:  Arctic Waste Disposal, Report No.
        74-10, Environmental-Social Program, Task Force on Northern Oil
        Development, Government of Canada, Ottawa, Ontario, 1974.

24.  Sletten, R.S., Feasibility Study of Land Treatment at a Subarctic
        Alaskan Location.  IN:  R.C. Loehr, Land as a Waste management
        Alternative, Ann Arbor Science Publishers, Michigan, 1977.

25.  Smith, D.W., Land Disposal of Secondary Lagoon Effluents, Pilot
        Project.  Institute of Water Resources Report No. 59, Univ. of
        Alaska, Fairbanks, 1975.

26.  Hartland-Rowe, R.C.B. and P.B. Wright, Swamplands for Sewage
        Effluents, Final Report.  Environmental-Social Committee,
        Northern Pipelines, Department of  Indian Affairs and Northern
        Development, Ottawa, Ontario, 1974.

27.  Fetter, C.W., Jr., W.E. Sloey and F.L. Spangler, Use of a Natural
        Marsh for Wastewater Polishing.  Special Report of the Dept. of
        Geology, Univ. of Wisconsin, Oshkosh, 1976.

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                                 10-23
28.  Tilsworth, T. , Sludge Production and Disposal for Small Cold Climate
        Bio-Treatment Plants.  Institute of Water Resources Report No.
        IWR-32, Univ. of Alaska, Fairbanks, 1972.

29.  Ostrom, T.R. , et_ al, Investigation of a Sewage Sump on the Greenland
        Icecap. Jour. W.P.C.F., 34_, 1, 56, 1962.

30.  Reed, S. and Tobiasson, Wastewater Disposal and Microbial Activity
        at Ice-Cap Facilities, Jour. Water Poll. Control Fed.  40, p.
        2013, 1968-70.                                     ~

31.  Heinke, G.W. and D. Prasad, Disposal of Human Wastes in Northern
        Areas.  IN:  Some Problems of Solid and Liquid Waste Disposal in
        the Northern Environment.  Environment Canada Report EPS
        4-NW-76-2 pp. 87-140, 1976.  Also in Proe. 3rd Canadian
        Hydrotech. Conf., Canadian Soc. Civ. Eng., Laval University,
        Quebec, 1977. pp. 578-593.

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                                 SECTION 11
                    CENTRAL FACILITIES AND REMOTE CAMPS
                                    Index

                                                                     Page
11       CENTRAL FACILITIES AND REMOTE CAMPS                         11-1
11.1     Introduction                                                11-1
11.2     Central Facilities                                          11-2
11.2.1   Level of service                                            11-2
11.2.2   Design population and flows                                 11-7
11.2.3   Selecting and sizing services                               11-8
11.2.4   Space considerations                                        11-14
11.2.5   Water supply and treatment                                  11-15
11.2.6   Wastewater treatment and disposal                           11-16
11.2.7   Energy conservation                                         11-19
11.2.8   Fire protection                                             11-26
11.2.9   Construction techniques                                     11-27
11.2.10  Cost factors                                                11-29
11.3     Remote Camps                                                11-30
11.3.1   History                                                     11-30
11.3.2   Facility description                                        11-31
11.4     References                                                  11-34
11.5     Bibliography                                                11-35

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                              List of Figures
Figure                                                                Page
11-1     Environmental Service Module                                 11-4
11-2     Aerial View of Central Facility                              11-6
11-3     Ground View of Central Facility                              11-6
11-4     Typical Honeybucket Dump Station                             11-18
11-5     Water, Wastewater and Heat Flow AVDP -Wainwright,  Alaska    11-20
11-6     Example of Energy Recovery from a Diesel  Generator           11-21
11-7     Schematic of Incineration Process                            11-25
11-8     Relationship Between Fuel Consumption and Moisture
         Content of Solid Waste During Incineration                   11-25
11-9     Road/Pipeline Construction Camp                              11-32
11-10    Drilling Rig Camp                                            11-32
11-11    Layout and Utilities for a Pipeline Construction  Camp        11-33
Table
11-1
11-2
11-3
11-4

11-5
                             LIST OF TABLES
Central Facilities in Alaska:  Services Provided
Distribution of Space in a Typical Central Facility
Typical Laundry Wastewater Characteristics
Construction and Operating Costs for Three
Central Facilities
Remote Camp Sizes and Durations
                                                            Page
11-5
11-15
11-17

11-29
11-34

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                                    11-1


11        CENTRAL FACILITIES AND REMOTE CAMPS
11.1      Introduction
          Many cold climate communities are located where  it  is  difficult,
if not impossible, to construct and operate conventional water  supply  and
wastewater systems piped  to the individual homes.  Ice-rich  permafrost,
soils with deep frost penetration,  rock, and low density distribution  of
housing are among the factors limiting the use of conventional water
supply and wastewater system services in some communities.   Nearly  all
such communities are native villages with less than 600 people.
          One alternative  for these communities is to  provide at least one
facility, centrally located, where  certain sanitation  services  can  be
obtained.  For example, a  central facility might provide a place to obtain
safe water to drink, a  sanitary means of waste disposal, a place to bathe
and a place to launder  clothes.  Any combination of these  sanitation
services may be provided.
          This section  discusses the design considerations for  providing a
central facility in communities where piped services to individual  houses
are not feasible.  Considered in the discussion are the level of service
to be provided, sizing  of  utilities and services, energy conservation,
fire protection, construction techniques and cost factors.
          In addition to  those people who have lived in the  cold climate
regions for thousands of  years, the search for oil, gas and  minerals has
brought industrial workers to the far north in large numbers.  Also man
eomes to the cold regions  for purposes of national defense,  research,
communications, and development of  other natural resources.   Early  housing
and utility services were  crude.  Now, however, improved temporary  and
permanent camp facilities  enable workers to live in relative  comfort,
safety and health with  a minimum impact on the environment.
          The central facility concept for achieving sanitation  services
has application in remote  camps as  well as in villages.  The  need for
sanitation services and environmental protection is similar  in  remote
camps and in the villages, but they are discussed separately  in  this
manual because the economic, social, cultural, institutional, and operation
and maintenance aspects of the facilities are so different.

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                                   11-2
          Remote camps include those used by the natural resource
development industries in support of their efforts to explore, develop,
and produce natural resources.  In addition, there are large  temporary
pipeline construction camps, small permanent pump station camps and
industrial services camps.  The military uses remote camps to  support
its DEW line facilities, and is interested in more efficient  remote  camps
for troops in the Arctic.  There are also remote eamps for road
constructors and developers of other natural resources.
11.2      Central Facilities
11.2.1    Level of service
          Central facilities can provide a variety of levels  of service,
depending on the needs and desires of a community, convenience, the  cost
of operating and maintaining the system, and funds available.
          Defining the level of service to be provided is not  always easy,
but it is one of the most important considerations in the early stages  of
a project.  Decisions on the types of services  to be provided  should be
made only after carefully considering funds available for construction;
operation and maintenance available within the  community and  from  outside
sources; what the community wants; social and cultural customs; community
willingness to participate in  the project; availability of good operators;
and availability of technical  and management expertise.  Section 2
provides other useful information to consider during  the planning  stage of
a project.
          Realistic consideration of these factors with  the meaningful
participation and involvement  of the community  in the decision-making
process is essential  to, but in no way a guarantee of, a successful
project.  A successful  project is one which  satisfies the  sanitation needs
of the people for whom  it is built.
          A minimum level of service for a central  facility might  be a
simple watering  point from which people  can  obtain  safe  water to drink.
This single service may  be appropriate  for  some communities based  on the
above considerations.   It is discussed  in detail in  Section 6.
          Other  services  to be considered include  providing a place to
wash and dry clothes, bathing  facilities, a  place  to  safely dispose of

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                                    11-3
honeybucket and other  wastes,  toilets  and wash  basins.   Saunas can
supplement the use  of  showers, but  local custom,  and  willingness to  use
them and pay for  their use, must  be  carefully considered  before they are
installed in the  facility.  Figure  11-1 from Brown, et  al [1]  shows  a
floor plan for a  typical  central  facility.  Table 11-1  lists the services
provided in 14 typical central facilities constructed in  Alaska.
          Central facilities often may be constructed as  the first
installment on a more  complete system.  Therefore, each central facility
should be designed  so  that  its basic water  supply and wastewater treatment
systems can be expanded to  provide  increased service.  Typical expanded
services might be a haul  system,  or  in some cases, a  water  and sewer
system piped to individual  houses.
          Whenever  possible, arrangements should  be made  for the central
facility to serve or be served by other major community facilities such  as
schools, health clinics and power generating facilities.  The  revenue
produced by serving these facilities can be substantial and  provide
stability to the  income derived from community  use of the central
facility.  Also,  the use  of electricity and waste heat  from  community or
other large power plants  can result  in fuel savings and significant
increases in overall system efficiency.
          Experience with central facilities has  been limited  to
communities between about 25 and  600 people.  Most of the facilities have
been one or two storey structures with between  80 and 325 square metres  of
total floor space.  Roughly half  the space  is used directly  by the
consumer, while the mechanical operations,  storage space  and operator work
areas account for the  remainder.  Typical central facilities are
illustrated in Figures 11-2 and 11-3.
          When facilities are constructed in remote areas of the North,
where the climate can  be exceedingly unforgiving  and  where  electrical
power service may be unreliable,  the most important design  criteria  are  to
simplify construction  and operation, and provide  a high degree of
reliability.  Unfortunately, this is easier said  than done.   To deal
effectively with the harsh climate and with some  of the difficult water
supply and waste disposal problems encountered  in the Arctic,  some degree
of complexity is frequently unavoidable.

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03
CD
s_
03
c:
o
       Toilets and bathing
CD ^^>
O  /
  /
Laundry
cc d
       Toilets and bathing
                             Sauna
                                  Water
                                production
O  Process
 , control  i
   laboratory
O
                                       Waste treatment
                         /oauna
                    s  v.
                                       o
                                         o
                                               Drive-way
               FIGURE 11-1.  ENVIRONMENTAL SERVICE MODULE [1]
                                                                I
                                                               -p-

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                              TABLE 11-1.  CENTRAL FACILITIES  IN  ALASKA:   SERVICES  PROVIDED
Community
Wainwright I*
Wainwright II
Emmonak


Northway
Chevak
Nulato

Selawik

Alakanuk

Pitkas Point
Koyukuk
Beaver
Kongiganak
Tanana
Council

Population

341
545


40
447
330

521

512

85
124
101
200
450
25

Water Point
yes
yes
yes


yes
yes
yes

yes

yes

yes
yes
yes
yes
yes
yes

Washers
4
4
4


3
3
4

4

4

3
3
3
4
6
no

Dryers
4
5
3


3
3
4

4

4

3
3
3
4
6
no

Showers
8
8
8


2
,2
4

4

4

4
3
3
6
8
no

Toilets
8
8
6


2
0
6

6

6

4
3
3
4
4
(privies)
yes
Saunas
2
2
2


no
no
2

2

2

2
no
2
no
no
no

Incinerator
yes
no
yes


no
no
yes

yes

yes

no
no
no
no
no
no

Honey-
bucket
Dump
yes
yes
yes


no
no
yes

yes

yes

yes
yes
yes
yes
yes
no

Other
Facilities
Served
Schools
Schools
Schools,
Community
centre
Clinic
Clinic
School ,
Clinic
School ,
Clinic-
School,
Clinic
School
School
School
School
School
none

*Wainwright I was destroyed by fire in 1973.

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                      11-6
FIGURE  11-2.  AERIAL  VIEW  OF  CENTRAL FACILITY
FIGURE 11-3.  GROUND VIEW OF CENTRAL FACILITY

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                                   11-7
11.2.2    Design population and flows
          Specific design criteria for the services selected  are as varied
as the communities.  First, the design population, water  supply
requirements, and the amount and type of wastewater must  be considered.
          The following example, from the Alaska Department of
Environmental Conservation (ADEC) [2], is presented to  illustrate one way
to estimate these design criteria.  The approach was used  to  design a
central facility for the small community of Pitkas Point  on the lower
Yukon River in Alaska.  (Minor modifications have been  made in the example
for this manual.)
          The community had a population of approximately 80  people.
There were about 15 houses within a radius of 0.5 km.   A  small creek by
the community provided a good, reliable source of water.   There was a
one-teacher school located near the centre of the community.  No
permafrost existed and soils were generally silty sandy gravel with a
water table over 7 m deep.  Electrical power was available from the nearby
community of St. Marys and a good gravel road connected the two; no other
utility services were available.  Water was carried in  pails  from the
creek to the homes and honeybuckets were dumped into the  Yukon River.
          Allowing for growth, the following assumptions  for  design
populations and per person loadings were used:
          - 120 people and 20 families @ 10 L/person/day;
          - one teacher plus a family of three @ 375 L/person/day;
          - 40 students @ 60 L/student/day;
          - one honeybucket per family/day @ 20 L/bucket  and
            50 000 mg/L BOD loading (includes some grey water);
          - two showers/person/week;
          - three water closet uses/person/week (assume low
            water use toilets);
          - one washer load/family/day.
Daily water flows were determined as follows:
           Laundry:  20 x 160 L/use                  =  3 200
           Showers:  120 x 2/7 x 120 L/use           =  4 115
           Water Closets:  120 x 3/7 x 15 L/use      =     475

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                                    11-8
          Teacher (and family):  4 x 375 L/person   =   1  500
          Students:  40 x 60 L/person               =   2  400
          Honeybuckets:  20 x 20 L/family           =     400
          Miscellaneous:                            =     375
               Subtotal (wastewater)                =  12  365  L/d
          Offsite use:  102 x 10 L/person           =   1  200
               Subtotal                             =  13  565  L/d
          Total Water Consumption (less honey-
           bucket wastes) = 13,565 - 400            =  13,165  L/d
          Based on the assumptions and calculations outlined  above,  a
water supply rate of 14 000 L/day and wastewater flow  of  13 000 L/day  were
selected for design purposes.
          At the present time no definitive studies exist  to  provide the
designer with exact criteria on water supply and waste  flows  for  central
facilities.  Until such data can be obtained from existing and future
central facilities, rational approaches to arrive at these design
criteria, such as illustrated above, can be used.
11.2.3    Selecting and sizing services
          Selecting sizes and types of service (showers,  laundry,  saunas,
sewage dump station, washrooms, etc.) must be done on  a case-by-case basis.
Careful consultation with people in the community (perhaps even with the
use of a well designed, administered and interpreted questionnaire [3]) is
essential to providing the best possible service.  The  questions  that  must
be answered include:  How many hours per day and per week  will the facility
be open?  How often will people use the services provided  per day  and per
week?  How much are the people willing to pay for the  services?   Given the
community responses to the questions, some design estimates can be made.
          One formula used by ADEC [3] for determining  the number  of units
(showers, washers, and dryers, etc.) is as follows:
          NUMBER  =    uses/week x cycle time/use  x p.p.              (11-1)
                           time available/week
where:  P.F. is a peaking factor to account for the fact  that use  of a
        service will not be spaced evenly throughout an entire week.
        Typical P.F. values for design might range between 1.5 and 3.5.

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                                    11-9
11.2.3.1  Washers.   Commercial washers  should  be  used.   They range in
capacity from 6.8 kg  (weight  of  dry  clothes  that  can  be  placed in them)
up to about  15.9 kg.   An  average washer cycle  is  about  40 minutes
including loading and  unloading  time.   Smaller  units  are significantly
cheaper, but larger  ones  can  handle  bulky  items such  as  sleeping bags,
small blankets, and  parkas, and  have proved  particularly useful.
          Horizontal  axis washers, and  especially washer-water
extractors,  tend  to  vibrate during use  [4],  It is, therefore, necessary
to provide a solid base such  as  concrete or  heavy timbers to prevent  the
vibration.  Vertical  axis washers do not vibrate  as much, but they are
normally available only in  smaller sizes.  Top  loading vertical axis
washers also use about 40% more  water than the  front  loading horizontal
axis machines for an  average  wash load  [5].
          Past facility designs  have frequently used  two loads/family/
week to estimate  the  number of washing  machines needed.   In  smaller
communities where the  facility will  be  conveniently located, designs  of
one load/family/day  have  been used.   As noted  earlier it is  important to
seek guidance from the community involved  to arrive at a suitable use
factor.  As a practical matter,  a minimum  of three washers and three
dryers should be provided, regardless of community size.  This will
enable service to continue on a  more or less uninterrupted basis when one
or more of the machines is out of service.   Dependability of service  is
important to user satisfaction with  the central facility. Also, the
units should be installed so  that they  are readily accessible for
maintenance and repair.
11.2.3.2  Dryers.  There  are  many types of dryers available:  hot water,
electric, steam, hot air, and hot liquid.  It  is  difficult to choose  the
"best" type for a particular  application.
          Electrically operated  dryers  are the  easiest to maintain but
they are also the most expensive  to  operate.  According  to ADEC [2],
electrical energy can cost over  ten  times  as much as  that derived from
bulk fuel oil.  ADEC  [3]  calculated  that for an 8.2 kg capacity dryer
requiring 21.6 MJ/h (5.9  KW), 45 minutes/load and $0.056/MJ  ($0.20/KWh),
a very low electrical cost in remote areas,  the electrical cost for

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                                  11-10
heating alone would be $0.89/load.  Comparable heating  costs  using  oil
were calculated to be about $0.11/load.
          Hot water has been used for dryers in  several  central
facilities with satisfactory results.  One major disadvantage of  hot
water is the likelihood of broken or damaged pipes and  heat exchangers  in
the event of freezing.  Hot water as a source of dryer  heat is also of
marginal quality.  In order to  provide sufficient heat  to  the dryers,  the
hot water system must be operated at its upper limit  for temperature  and
pressure.  This increases the chance of vapour locks  in  the system  due  to
"flashing".  Hot water dryers are not commercially available, although
steam operated dryers can be used with virtually no modification.   The
primary advantage of hot water  dryers is that they can  be  run directly
off of a single hot water furnace, which may also provide  building  heat
and a domestic hot water supply.  Also, remote community operators  are
generally more skilled in the operation of hot water  heating  systems  than
steam heating systems.
          A hot air furnace with appropriate duct work  can provide  dryer
heat.  Such a system requires one less heat exchanger and  is  not  damaged
by freezing, but ducting must be well insulated  to reduce  heat losses
and, most important, an extra furnace is required [3],   Advantages  and
disadvantages of separate vs multipurpose  furnaces are  discussed  in
Section 11.2.7.3.  Dryers heated by hot air furnaces  are not  commercially
available, but typical electric dryers can be converted readily  for this
application.
          Steam operated dryers would appear to  be a  good  choice  because
of the excellent heat carrying  capacity of steam.  However, few  people  in
the remote areas are familiar with the principles and operating
characteristics of steam systems.  In addition,  the relatively high
operating temperatures and  pressures require more maintenance.  Freezing
can damage steam dryers (although the potential  is somewhat less  than
with hot water) and  the heat exchanger coils tend to  require  frequent
cleaning to maintain efficiency.
          Hot organic fluids such as "Dowtherm"  or "Therminol" can  also
supply dryer heat  [6,7].  These systems can be  efficient,  although they

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                                   11-11
operate at relatively high  temperatures (177C).   Numerous  operational,
maintenance, and safety problems can occur,  particularly  if initial
construction is poor [5],   One advantage, besides  efficiency,  is  that
freezeups do not result in  damage  to this type  of  heating system.
          Experience indicates that dryers generally  should be sized at
least 1.5 to two times larger than the washers.  This will  accommodate
the tendency for people to  put more than one washer load  in a  dryer and
will also account  for the fact that it generally takes longer  to  dry
clothes than to wash them.  Appropriate dryer  sizes can be  determined
after the washers  are selected.
          Drying cycle times vary  with the type of system used.
Manufacturers' literature can provide this information.  For hot  water
systems, the cycle  time will be about 45 minutes.  An additional  10
minutes to load and unload  clothes can be used  when estimating total
cycle times.
          There are many acceptable brands of  washers and dryers  readily
available on the market.  After the type and size  of  equipment have been
selected, the choice of model should be based  on the  availability of
spare parts and the range of sizes available.
11.2.3.3  Showers.  The number of  showers required can be estimated using
Equation 11-1.  The showers normally should  be  divided between men's and
women's shower rooms.  Previous designs have frequently used two
showers/person/week for usage rates and an average use time of about  10
minutes.
          Because  of the great expense of heating  water,  shower  flows
should be limited  to the extent practicable.   Inaccessibility  of  a water
source and difficult treatment requirements  will also dictate  the  need
for water conservation.  Timers, flow regulators and  flow shower  heads
are the most useful devices for oonserving water.  Reid [6]  reports
adequate and satisfying showers using only 23  L/shower with these
devices.  Conventional shower heads use about  25 L/minute,  while  low flow
shower heads with  flow rates of 5  to 12 L/minute are  readily available at
a cost of approximately $10 [5],

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                                   11-12
          Minuse Systems Inc.  [8] reports a device  which  ean  give  an
adequate shower using only  1-2 L/minute.  The  special  shower  head  mixes
water with air from a small electrically operated blower  to create a fine
stream effect.  A glass or  rigid door  is required for  the  shower  stalls.
The increased complexity and oost of this system must  be  compared  with
the apparent water and energy  savings.  Alternatively, with a simple self-
closing hand-held shower unit, developed by the U.S. Navy, an adequate
shower can be obtained with only 10 L  of water [9].  More  detailed infor-
mation is available in Appendix B.
11.2.3.4  Saunas.  Early central facilities included saunas primarily as
a means to reduce water consumption, based on  the premise  that actual
"bathing and cleansing" would  take place in the sauna  and  the showers
would then be used simply to rinse off.  Since saunas  use  virtually no
water, savings were anticipated to be  substantial.  However,  experience
has shown that persons taking  saunas take showers not  only to rinse, but
to cool off as well.
          The other reason  saunas were included is  that they  are  a part
of the native culture in many  southwest Alaska communities.   In those
communities where saunas are not part  of the local  custom, they are not
used enough to justify their installation.  If not  used,  saunas do not
generate enough money to pay for operation and maintenance.   Reid  [6]
reports that saunas consumed 14.2 percent of the total fuel used  in the
central facility at Emmonak, Alaska.
          Nevertheless, the saunas in  the central facilities  at Emmonak,
Alakanuk, and Pitkas Point  in  Alaska are extremely  popular and
successful.  Saunas are a local custom in these communities and the
people are attracted to the central facilities to use  the  saunas  and
socialize.  These saunas produce substantial revenue;  for  example, in
Alakanuk and Pitkas Point, approximately 2/3 of the total  revenue  from
the village is attributable to use of  the saunas.   These  people are
clearly willing to pay the  cost of providing the sauna service, and
more.
          Saunas represent a special challenge because it  is  very
difficult to provide the high  quality  of heat needed to make  them operate

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                                   11-13
satisfactorily.   Saunas  constructed  in  central  facilities so far have
used  sauna  stoves  as  a  source  of  heat except  for one that has used waste
heat  from an  incinerator [4],   Electric sauna stoves are the easiest to
maintain; however,  they  can  be prohibitively  expensive to operate.  Also
used  are fuel oil  fired  sauna  stoves.   They perform adequately and are
reasonably  efficient, but  can  be  a safety  hazard.   Overheating can cause
cracks in the fire  box allowing fumes to escape  into the sauna room.
          One promising  concept uses hot water  from the central building
heating system in  series with  an  electric  heater.   The bulk of the
heating needs can  be  provided  by  the low cost oil-fired system.  The
electric heater must  only  provide the small increment of heat which is
not available from  a  conventional hot water system.
          With a regulated heat source  and plenty  of insulation, the cost
of operating a sauna  can be  reduced. Maintenance,  of course, is
negligible  other than that needed for the  heating  source.
11.2.3.5  Restrooms.  Most central facilities providing more than just
a simple watering  point  also should  provide restrooms.  There should be
separate men's and  women's restrooms, each with  lavatories and toilets.
Equation 11-1 can be  used  to derive  the number needed.  In central
faeilities  serving  large communities, urinals should be provided for the
men's room.
          Lavatories  are not unique  to  central facilities and need little
discussion  except to  suggest that where water is scarce or expensive to
treat, they should  have  automatic closing  valves.
          Where water is readily  available at low  cost, flush tank
toilets are appropriate.  They are simple  to  operate and require no
additional  power source.  Nevertheless, conventional flush toilets which
use an average of 20 L/flush are  unnecessary.  Flush toilets which
operate on  the same simple principles as the  conventional variety but use
only about  3 to 12  L/flush are  readily  availalbe [5,  10].  For virtually
the same operation  and maintenance costs,  considerable savings can be
realized over procuring, treating  and pumping  the  water,  and treating and
disposing of the wastewater.

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                                  11-14
          Where water is in short supply, or procurement or  treatment
costs are high, other types of toilets should be considered.  One  such
toilet has a vacuum rather than gravity collection  system  and only uses
about 1.5 L/flush [5],  Recireulating chemical  toilets use only about  10
to 30 L of water per 150 flushes [5],  The contents of the reoirculating
toilets can be transported to the treatment system  by vacuum, gravity, or
manually.  Substantial water savings can be realized with  these systems,
but there are chemical costs and mechanical systems to be  maintained.
Units are available which flush mechanically or electrically.   Reid  [7]
concluded that recirculating toilets installed  in central  facilities  were
of poor design for the application and were fragile.  Refer  to Appendix B
for details on available toilet units.
11.2.3.6  Water storage.  Central facilities should have storage
capacity for treated water.  Depending on the reliability  and
availability of the water source, water source  flow capacity, and  fire
flows, storage may range from less than one day's to nine  months'  design
flow.  The amount of storage should be sufficient to ensure  a minimum
level of service for the duration of any anticipated power outage  or
equipment breakdown.  Storage capacity amounting to about  one day's total
design flow has been used frequently for central facilities  where  water
sources are reasonably available and water treatment requirements  are not
unusually difficult.  Water conservation will ensure several days  reserve
to provide minimum services such as drinking water  supply  and showers.
Details for sizing and designing water storage  systems are contained  in
Section 5.
11.2.4    Space considerations
          Lack of sufficient spaee has been a serious problem in  previous
central facilities.  The early emphasis on saving space  resulted  in
problems for both operators and users of the facilities.   Equipment and
facilities were squeezed together so much that  vital repair  and
maintenance functions oould not be performed without major efforts to
move  piping and equipment.  Inaccessibility breeds  frustration and
inattention by operators and necessary maintenance  routines  are not
performed.

-------
                                   11-15
           Vital components must be easily accessible.  Piping must be
 arranged so it does not interfere with basic maintenance and repair
 functions.  Critical piping joints should not be located in walls.  If
 they must be placed in walls, then removable panels should be provided
 for easy access.   In addition, cramped space in the user's portion of the
 facility discourages use.
           One of  the more frequently overlooked space requirements for
 central facilities in remote areas is storage space.  Transportation of
 bulky items like  chemicals and general supplies to many remote
 communities is often limited to once per year.   Hence, storage areas need
 to  be sized to accommodate this quantity of supplies.  Another often
 overlooked requirement is space to work on pumps and motors and to
 perform other general repair and maintenance functions.  Table 11-2 shows
 the distribution  of space among services and operating functions in a
 typical central facility with average water supply and wastewater
 treatment requirements.
     TABLE 11-2.  DISTRIBUTION OF SPACE IN A TYPICAL CENTRAL FACILITY
 SPACE	PERCENT OF TOTAL	
 OPERATION
      Chemical/materials storage                    10
      Operator repair/office                        10
      Water treatment                                5
      Wastewater treatment                          10
      Heating/ventilating                            5
           Subtotal                                  40
 SERVICE
      Laundry                                        25
      Sauna/shower                                   15
      Restrooms                                      10
          Subtotal                                  50
MISCELLANEOUS                                       10
	TOTAL	100  percent	
11.2.5    Water supply and treatment
          A central facility must  provide water  that is  chemically  and
bacteriologically safe, which is more convenient  than  other  sources,

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                                  11-16
and which tastes and appears better than alternate sources.  Providing
the degree of water treatment to meet these requirements is essential if
the facility is to be used.
          The central facility concept has some options for water  supply
and treatment that are not normally available to piped utility  systems.
For example, where good water is scarce or treatment is difficult,  the
central facility can use a small system for potable water only  (showers,
lavatories and drinking).  Other needs for toilet flushing and  laundering
might be met with recycled water or water of less than drinking water
quality.
          Special effort should be made to ensure the best raw  water
quality possible before it is brought to the central facility for
additional treatment prior to being used.  For example, an infiltration
gallery might be used, where appropriate, to provide a minimum  level of
pretreatment and reduce the need for more extensive in-house treatment.
          Otherwise, water supply and treatment requirements for central
facilities are not particularly unique compared with other water supply
needs in the Arctic.  Details on water supply and treatment systems are
discussed in Sections 3, 4 and 6.
11.2.6    Wastewater treatment and disposal
          Detailed wastewater treatment and disposal alternatives  are
discussed in Sections 9 and 10.  These alternatives, with modification,
are appropriate for central facilities.  For example, special
consideration must be given to treating laundry wastes, large variations
in influent temperatures, foaming, shock loads from honeybucket wastes,
and the fact that, hydraulically, flows will be limited to the  operating
periods of the facility unless other users, such as schools, are serviced,
          A major portion of the wastewater flow in a typical central
facility will come from the washing machines.  Laundry wastewater
resembles domestic wastewater in many ways (see Table 11-3)  [11] but it
does not contain all of the essential nutrients to sustain the  organisms
necessary for effective biological treatment.  This problem can be
overcome by adding domestic wastewater from toilets and honeybuckets, and
by serving other facilities such as schools.

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                                  11-17


TABLE 11-3.  TYPICAL LAUNDRY WASTEWATER CHARACTERISTICS
                                            Range (mg/L)
Substance
ABS
Suspended Solids
Dissolved Solids
COD
Alkalinity
Chloride
Phosphates
PH
Nitrates
Free Ammonia
Sulfates
BOD*
Temperature*
Coliforms*
Minimum
3.0
15.0
104.0
65.0
61.0
52.0
1.4
5.1


80.0
20C
Average
44.0
173.0
812.0
447.0
182.0
57.0
148.0
1.0
3.0
200.0
1260
21C
2000/100 ml
Maximum
126.0
784.0
2064.0
1405.0
398.0
185.0
430.0
10.0


371.0
22C
*Based on data reported by Aulenbaok, et al [11].

          Sudsing detergents can cause excessive foaming.  The  use of  low
suds detergents is essential to control this problem.  Large  temperature
variations due to laundry (hot), toilet flushes (cold) and showers (warm)
ean be upsetting to treatment systems.
          Central facilities should be designed to handle honeybucket
wastes, but experience shows it is very difficult to get people to use  it
for that purpose.  Many people seem to be self-conscious about  carrying
their own honeybuckets to the central facility for disposal and prefer,
instead, to dump the wastes near their homes.  Figure  11-4 shows a
typical honeybucket dump station in a central facility.
          A large flow equalization system is essential to overcome
treatment problems due to flow variations.  Where package sewage
treatment systems are used, the rule of thumb for conventional  design  is
10-20 percent of the average daily flow volume.  For central  facilities
where the entire flow can be assumed to eome in 10 hours or less, it could
be necessary to provide holding capacity for over 50 percent  of the
average daily flow for proper equalization.  Therefore, for design
purposes the flow should be spread over a 24-hour period (at  least for
small biological package treatment systems).  The volume of the
equalization system depends on the actual flow regime, with at  least
50 percent of the average daily flow volume being needed in many,

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                                     11-18
if not  most, cases.   In addition, multiple package  treatment  systems  in
parallel can often be used  effectively  to handle  large variations in  flow.
           Data on  the characteristics of  wastewater from central facilities
are very limited.   Nevertheless, data from three  facilities which provide
all services offered in central facilities in addition to  servicing adjacent
schools suggest  that BOD,  COD and total  solids are  roughly 300 mg/L,  700
mg/L and 1600 mg/L,  respectively [4].   Suspended  solids ranged from about
400 mg/L to 1365 mg/L, with no apparent  reason for  the higher  value which
was an  average of  five samples.
          Treatment of wastewater at central facilities can consist of any of
the conventional  techniques,  including  lagoons, aerated lagoons, lagoons
with pretreatment  (such as  simple aeration), biological extended aeration
and physical-chemical.  Even  wet oxidation has been suggested  for remote
military camps by  Brown et  al [1],  No  single technique can be recommended.
Once effluent standards are established,  however,  the system which offers the
least  operation  and  maintenance requirements should be used where possible.
                       25L Toilet flush tank
                Galvanized metal wainscot
                1200 above floor
                25 Supply line connected
                to flush ring in cone
                50 x 100 Nailed to wall
Provide handle in dump room
to operate flush tank
 Wall brace
  1 0 Copper line for bucket rinse
            Fabricated strainer from
            No 8 Copper rod spaced
            50 apart Braze all joints
       25 Copper pipe around perimeter
       Provide 3mm holes in bottom at
       25 OC solder to cone
                                                           Overlap to top and secure
                                                           with nichol plate F H screws
                                                           Galvanized 20 guage steel cone
                                                           100 Spigot
                                                           No hub coupling
                                                           100 ABS-DWV to trap
                                                Note Seal all pints with silicone sealant
                 FIGURE 11-4.   TYPICAL  HONEYBUCKET  DUMP STATION

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                                   11-19
          Puchtler et al  [4] concluded  that  the cost  of operating  and
maintaining water-related utilities in  rural Alaska  is directly  related
to the level of waste treatment  provided.  Although  costs  can  be
substantially higher for  complex wastewater  treatment systems, the Alaska
Department of Environmental Conservation operating experience  suggests
that wastewater treatment is not a major factor when  compared  with the
total cost of providing the other services in a central facility.
11.2.7    Energy Conservation
          Section  14 provides details on this subject.  The  following
discussion pertains primarily to those  aspects of energy conservation
related to central facilities.   Figure  11-5  shows a  detailed energy
balance diagram for a central facility  at Wainwright, Alaska,  using
several energy conservation techniques.
11.2.7.1 Electrical power.  A dependable source of electrical  power is a
critical ingredient in operating a central facility  in remote  areas.
Seldom, however, do the small communities in cold climates have  reliable
sources of electricity, due primarily to the difficulty of operating and
maintaining diesel-powered generator systems.  In many communities,
operators are poorly paid and funds are rarely sufficient  to support even
minimum preventive maintenance routines.  Other communities  do not have a
source of electrical power and it must, therefore, be provided as  part of
the central facility.
          In all cases, standby  power is essential.   A standby source of
power for building heat would be the minimum acceptable.   Capability to
provide the other central facility services  is based  on the  importance of
the service to the community and judgement on the reliability  of the
primary electrical energy source.
          Electrical power in remote areas frequently varies greatly in
voltage and frequency.  Such fluctuations reduce the  useable life  of
electrical high and low voltage and frequency protectors.  Here  again,
however caution must be exercised.  Rarely can the operators of  central
facilities repair or adjust these electrical controls without  training
and assistance.  Skilled electricians must sometimes be sent to  the com-
munity to perform necessary repairs.  This is a significant  disadvantage of

-------
-UTILIDOR  DUCT   OO' long - 2"4> Water Lines
84'$x24'Ht 1
Capacity - Max
25' - U Factors
Roof 0 066 , F
Maintained obo-
OOO.OCO Gol /
^d DifferentKil /
Walls 0092, 1
oor 0 147 f
*e Freezing 	 ^ 	 )  	 	
1464 - Operating H
STORAGE TANK 'JJ *" '
Not; Full tank sufficient for
8 month operation based
anon annual usage factor
of 60%
Des 651
f
""
	 ) 	
(55n F I
Des 651
(55-F ^
covered with 2 nsulation in
10" Duct with (" Insulation
and Alum num Clad
2115-24 Hrs/Day
-^ 143F)

1
Flow dur ng 24 Hr Period
, 2115 hi at 43'F a heated to
) < 55F U = 0 15
f 55F 1 	 1
RAW WATER STORAGE
| 2800 Gal

Overflow to Beach j
Des 350 *
160' F I
1 TREA

Des 468
f *~ (65-F) >
	 1
~ \-
TED WATER STORAGE
1400 Gal
RAW WATER TREATMENT 1

l_
\~~^^~
1000 GPD to Schoo
2000 GPD to Homes "5  ^ 	


	
POTABLE WATER STORAGE
2800 Go
Mox 725
	 	 Av9 351,
(Row during Oper-~l (55F) "
Avo9 ""9pl!"<)'ly
"?:? In of 55-F heated
ulu h IOIK3-F 24Hrs/ Mox 635
Day Insulated with ^ JQQ
" U = OII5g (55
POTABLE
WATER HEATER

F
Max 90
Avg 42
C55"F) ' '
I f ( (
Max 540 1 Max 66 Max 60|_ Max 15
Avg 270V ' 'Avg 32 Avg 2OT ' 'Avg 5
(I10F) I (55F (llOF) I (55F)
SHOWERS -
8 LAVATORIES- 4
Operating Period Only Operating Period Only
Mo Usage 75% of Time Max Usoge 12^% of Time
Avg Usage37 /?/,<$ Time Avg Usage 4 l/4%of Time
Mixed ShwrTemp )04F Mixed Temp 99F
Based on One Heod Use Based on One Sink Use
of I/^GPM 1 0F 8 of 2GPM IIOF a
0 I6GPM 55F VzGPM 55F
I
Max 700 1
Avg 332 1
&5F T

T
Max I5j_ Max 4
Avg 4T ' 'Avg 1
lllOeF)I (55F
_ABORATORY SINK- 1
Operating Period Only
vtax Usoge l2'/2%ofTime
fivg Usoge 3 'A %of Time
Mixed Temp 99F
Based on Sink Use of
2GPM IIOF a
'/SGPM 55 F
T
/ 	
TRE
Max I3
Avg 9C
' '(160-F
_, 	 ' 	 -^ Max 178
' ^^ Ava 1 18
Flow during Oper- <6nn
ating Perod only (6 F)
n of 60F heated
to!60F24Hrs/
Day Insulated with
2"Fiberqlass ^
U-II5 ^^
ATED WATER HEATER
575 Gol
Max 43
Avg 28
(60-F)

"j
Max 20 1 1 Max 5
Avg I5T T^vg 4
[||0F)I I(55F]
LAUNDRY SINK - 1
Operating Period Only
Max Usoge l67%ofTtme
Avg Usage l27%ofT.me
Mixed Temp 99 F
Based on Sink Use of
2GPM IIOFa
'/SGPM 55F
Neal(55F)
SAUNAS - 2
Heated 24 Hrs/Day In Use
ForOoeratina period On Iv
Normal Temp BOF with N
240F Capability mate A
up Air at 60"F Based N
on 4 Air Changes /Hr C
Operating Period K3% S
Losses During Off -Peak

V
2700 GPD (at Off -Peak
Ppnnd) r^turrtM fmm .*
(55 F by Truck * 	 ^- 	

Oes 468 n at 70 F
^ ^ 1 65-F
I4OO Gal
V
1
^-JF

CARBON FILTERS CLEAR FLOW UNIT

\ ^ ^
Max 60
Avg 40
160 F
Max 20 Max 75 Max 21 Max 2
1 ' 'Avg 13 AvgSO1 ' < 'Avq 14 Avg 1 ' '
160-F) (leVF (60-F) (60-F)
WASHERS SMALL-2 WASHERS LARGE-2 W C S - 6
Dperatmg Period Only Operating Period On y Operating Period Only
tax Usoge 75% of Time Max Usage 75% of Time Max Usoge837%of Tme
flgUsage 5O%of Time Avg Usage 5O%ofTime Avg Usage 50% of T me
achine Cycle 22 '/a Mm Machine Cyde 30 Mm Based on 6 Uses/ Hr
ycle Uses 15 Gal I60F Cycle Uses 25GaJ I60F (l6Uses Equal 1 Go )
5 Go 60F Water a 7 Gal 60F Water
T T V Y v
^ * I. V J ]To Incinerator |
^ 7

Occasional Washdown Only
WASHER SURGE 1


  ^. 	

200 Go Tola
1 Max 201 1

Des 136 . J
1 	 1 90F
Des 332 ^
                                                                                                                                                                                           I  The operating period is defined as lOhrs per day, 7 days
                                                                                                                                                                                             per week The off-peak period is the remaining Whrs per
                                                                                                                                                                                             day
                                                                                                                                                                                           2 Water flows are indicated beside the f tow lines An flows
                                                                                                                                                                                             are in G P H unless otherwise slated Maximum is the flow
                                                                                                                                                                                             tobeexpexted in anyone hour durng the operating period
                                                                                                                                                                                             and is used for the design of individual units Average is
                                                                                                                                                                                             the flow to be expected over the lOhr operating period
                                                                                                                                                                                             and is used for the overall system design Design is the
                                                                                                                                                                                             avg uniform flow to maintain a operate the system
                                                                                                                                                                                           3 Additional design criteria is given inside the illustrated
                                                                                                                                                                                             equipment boxes
                                                                                                                                                                                           4 Area heating calculations are based en
                                                                                                                                                                                              Outside ombient at -30 F
                                                                                                                                                                                              Minimum outside temp -56F
                                                                                                                                                                                              Building U-foctors (all U-factors in BTU/F/ftVrir)
                                                                                                                                                                                              Inside walls =0306 ,    Ceiling = 0036
                                                                                                                                                                                              Outside walls = 0057,
                                                                                                                                                                                              Sauna U - factors
                                                                                                                                                                                              Inside walls = 0 073,
                                                                                                                                                                                              Outside walls=0 033.
                                                                                                                                                                                                                   Floor =003O
                                                                                                                                                                                 Ceiling = 0025
                                                                                                                                                                                 Floor = 0 030
                                                                                                                                                            Drive thru U-foctors  as for building
                                                                                                                                                           The community complex area (washrooms, laundry,
                                                                                                                                                           entrance a center hall) is heated directly The drive
                                                                                                                                                           thru area is to be heated with a standard type unit
                                                                                                                                                           healer The raw and threated water areas are heated
                                                                                                                                                           both directly by the community complex area heater
                                                                                                                                                           and indirectly by heat transfer from process The inciner-
                                                                                                                                                           ator area is heated indirectly by heat transfer only
                                                                                                                                                         5 This flow sheet is intended only as an overall criteria
                                                                                                                                                           guide and does not indicate such items as pumps,
                                                                                                                                                           valves  etc
HEAT DATA IN BTUs / HR
Heat Use
Dryers
Community Complex
Heater
Treated Water
Heater
Potable Water
Heater
Raw Water Tank
Process ( 67.180)
Outside
Storage (140,7001
Saunas
Drive Thru Heater
Future
Total
Operating
Period
I40.0OO
151,600
76,900
143,500
207.B80
24,190
12,960
757.050
Off Peak
Period

24,750
1.900
1,900
142,680
6.020
4,430
181,680
Unit
Desian
105,000
(210.000)
183,000
168. 60O
218.200
265, 300
25.600
(51,200)
17,900
N A
                                                                                                                                                                                                COMMUNITY COMPLEX  HEATER
                                                                                                                                                                                          Based on maintaining Temp in Complex , Row Water
                                                                                                                                                                                          and Treated Water Areas at 60F 24 Hrs /Day
                                                                                                                                                                                          Washroom Shower Areas to be maintained at  TO'F
                                                                                                                                                                                          during Operating Period  PlemmTempat 100 F
                                                                                                                                                                                          4 Air Changes / Hr during the Operating Period 10%
                                                                                                                                                                                             Loss during  the  Otf -Peak Period  Make  Up Air
                                                                                                                                                                                          at Outside Ambient
                                                                                                                                                                                                                                                       NJ
                                                                                                                                                                                                                                                       O
SHOWER  SURGE TANKJ
     480 Go I lota I
                                   FIGURE   11-5.     WATER,   WASTEWATER  AND  HEAT   FLOW   AVDP  -  WAINWRIGHT,   ALASKA.

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                                  11-21
voltage and frequency protectors and must be considered  carefully  against
the need to replace or repair damaged electrical equipment.   In  spite  of
these problems the U.S. Public Health Service and ADEC use voltage
protectors because of their experience with damaging voltage  fluctuations
in villages.
11.2.7.2  Heat Recovery.  Heat recovery is discussed in  detail  in  Section
14.  Central facilities offer a unique opportunity to capitalize on  waste
heat recovery because of the relative closeness and availability of  heat
sources within the facility.  These sources may include  generators,
heating furnaces, building exhaust air, dryer exhaust air, incinerators
and warm water.  Recoverable waste heat can be used to supplement  heating
needs of a central facility including heat for saunas, hot water,  clothes
dryers, and building air.  Figure 11-6 illustrates an example where  80
percent of the total energy can be recovered from a diesel generator.  By
using efficient heat exchanges Reid [6] estimated that it is  possible  to
recover up to 50 percent of the net heat input to an incinerator.
                             Recoverable
                                exhaust
    FIGURE 11-6.  EXAMPLE OF ENERGY RECOVERY FROM  A DIESEL  GENERATOR

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                                  11-22
11.2.7.3  Heating system.  Another Important design  consideration for
central facilities is choosing a heating  system.  The  basic  questions to
be answered are:  What type of system  is  most  desirable  -  hot  water,  hot
air or steam? and should  there be a single  source of heat  to meet the
facilities heating needs  or should there  be separate sources of  heat
designed especially for the services where  they are  needed?  Answers  to
these questions require considerable analysis  of the heating needs and
the relative difficulty of maintaining  the  desired level of  service in a
central facility.  Nevertheless, the following is provided for general
guidance to the designer.
a)  Choosing the type.  Hot water heating systems are  the  most popular in
remote areas, probably because they are better understood  than other
systems.  With proper maintenance they  can  be  as serviceable as  other
choices.  The primary disadvantage of  a hot water heating  system is its
potential for damaging piping systems  during facility  freeze-ups.  Also,
hot water systems cannot  provide the high quality heat needed  for saunas,
and the heat available for hot water dryers is marginal.  Ethylene or
propylene glycol can be used with hot  water.   These  fluids can prevent the
freezing problems with hot water but they are  slightly less  efficient
(10-20 percent) in heat exchange properties than water,  require  more
attention in handling and maintenance,  and  can be corrosive.
          Inhibitors can  be used to control corrosion  but  they tend to
break down at high temperatures and maintaining  the  proper concentration
becomes another chore for operators.   One way  to achieve the higher
quality heat for all services in a central  facility  and  avoid  damage  due
to freezing is to use special organic  fluids instead of  water  or glycols.
These systems operate on  the same principle as hot water,  but  the fluids
can be fairly expensive and the plumbing  system must be  more elaborate to
handle higher temperatures.  Sloppy installation of  the  plumbing system
can be difficult to repair, and faulty joints  can leak hazardous fumes
into the central facility [4],
          Steam has a relatively high  capacity to carry  heat;  hence,  a
steam heating system can  readily meet  all of the heating needs in a
central facility.  The main disadvantages of a steam system are  that

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                                   11-23
people in remote areas are generally unfamiliar with  the  higher
temperatures and mechanics of  steam, and  the  hot  pressurized  vapour  is
more hazardous.  This makes operation of  the  steam  system more difficult
and results in higher maintenance  costs and down  time compared with  hot
air or hot water systems.  Pipe damage due to  freezing is generally
limited to low points or  restrictions in  the  piping system.
          Hot air does not have the heat  carrying capacity of water  or
steam, but it can be used effectively for dryers  and  saunas  if separate
heat sources are used and the  furnace is  close to the place  where  heat is
needed.  Hot air furnaces can  be used for building  heat also, although
controlling building pressure  becomes a problem,  and  ducting  consumes
more space than the plumbing for hot water systems.
b)  Single versus multiple heat sources.  A single  heat source (e.g., one
central boiler serving all heat needs) for a  central  facility offers
simplified maintenance requirements and reduced fire  hazards  compared
with several heat sources (e.g., separate heating vents for  building
heat, hot water dryers and other services).   Stand-by capability for a
single heat source can be partially achieved  by providing complete spare
burners.  Control systems for  distributing heat from  a single source are
more complex than individual control for  each  of  several  heat sources.
          Multiple heat sources can be used to meet the specialized
heating needs in the central facility.  They  can  serve as back-up  sources
of building heat since all units are not  apt  to be  out of operation  at
one time.  If multiple sources are selected,  compatible equipment  with
interchangeable parts should be used.  This will  reduce the  need for a
large spare parts inventory and make maintenance  easier.
11.2.7.4  Water conservation and reuse.   Fresh water  is extremely
difficult to obtain in many remote communities and/or complex treatment,
sueh as distillation, reverse  osmosis, or freeze-thaw techniques,  may be
required.  In addition, energy costs to run treatment equipment and
provide hot water can be  substantial.  Hence,  every effort should  be made
to reduce total water use.
          Where fresh water is scarce, or costly  to provide,  the designer
should consider ways to provide water based on quality needs. For

-------
                                  11-24
example, one can provide high quality water  for drinking water  fountains,
watering points, showers and lavatories by using a  small complex
treatment system.  A less complex  treatment  scheme  may  be  appropriate  for
toilets and washing machines.  Also, saline  or brackish water may  be
adequate for toilet flushing if it is readily available.
          Recycled water may be used for washing machines  and toilets  to
conserve water [6],  However, caution should be used  because of the
difficulty of providing consistently good effluents from wastewater
treatment systems.  In practice, physical-chemical  systems are  capable of
providing a fairly stable effluent suitable  for reuse in toilets and
washing machines, if they are operated properly.  Biological treatment
systems tend to produce erratic results and  secondary effluent  should  not
be reused unless additional treatment, such  as filtration,  is provided.
Dissolved solids in recycled water further complicate the  usefulness of
this water conservation technique.
          In summary, water reuse  involves costly and complex treatment
systems and equipment.  Where they are not absolutely necessary, water
conservation and reuse practices which add to the operating and
maintenance cost of a central facility probably have  limited value.
Water reuse is not recomended unless raw water is extremely scarce or  it
is difficult to treat.  It is usually more economical and  simpler  to use
to flow reduction techniques to reduce consumption  [9],
11.2.7.5  Incineration.  Incinerators have been installed  in several
central facilities for the primary purpose of disposing of waste
treatment plant sludges, honeybucket wastes, and other  solid wastes in a
sanitary manner.  Incineration theoretically offers an  "ultimate"
solution to the problem of organic waste disposal;  therefore, environmental
and health effects from these wastes can be  avoided.  Recognizing  that
incineration requires a substantial amount of fuel  oil, and electrical input
to "burn" the relatively wet wastes, extensive efforts  have been made  to
capture waste heat for reuse in central facilities.   Figure 11-7 illustrates
a typical incineration process used at several central  facilities  [7].
Figure 11-8 shows the relationship between fuel consumption and moisture
content of solid wastes during incineration.  Clearly,  significant fuel

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                                           11-25
                                                             Vapor to atmosphere
Dry refuse and garbage from
   Central facility
   School
   Homes
"Wet" wastes from
   Home "honey buckets
   School
   Toilets
   Process sludges
                              'Waste" heat used in
                                 Building
                                 Utihduct
                                 Clothes dryers
                                 Saunas
     Ash to land disbosal
 Combustion gases and heat
    
                                Co. for Wastewater treatment
                                   Secondary burner
                                   for pollution control
                                                                     Fuel oil and electrical inputs
                    FIGURE  11-7.   SCHEMATIC OF  INCINERATION PROCESS

                    Incineration  has been designed here to be  integral with
                    sewage  and solid waste disposal, and building heating.
                                 t
                                 o
                                 Q.
                                 E
                                 12
                                 OT
                                 C
                                 O
                                 o
                                  0
                                    0
          Solid waste
          moisture content
                   FIGURE  11-8.
RELATIONSHIP BETWEEN FUEL  CONSUMPTION
AND  MOISTURE CONTENT OF  SOLID WASTE
DURING INCINERATION

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                                  11-26
savings can be realized by dewatering high water content solid wastes.
An optimum moisture content can be determined by comparing  the cost of
removing the moisture to the corresponding cost of incineration.  This
optimum moisture content usually falls in the range of  25 to 40 percent.
          Little work has been done to establish good design criteria for
incinerators in central facilities.  The following information is based
on limited data [7]:  a heat recovery system performed  at 25 percent
efficiency (ability to achieve 50 percent recovery was  calculated by
making minor equipment modifications); the heat content (thermal value)
of dewatered black water sludge ranged between 2481 calories/gram and
3808 calories/gram, based on four samples analysed; and, about one  litre
of fuel oil was required to "burn" 15 L of sludge.
          In spite of the environmental and health benefits, incinerators
have not proved very successful in central facilities.  They are costly
to operate and controls are much too complex for  the  semi-skilled
operators in most small communities.  On the other hand, for remote
industrial camps where environmental concerns are great and costs of
operation and maintenance are not so critical as  for  community central
facilities, incineration offers excellent treatment  for combustible solid
waste  and sludges.  Section 13 provides additional information on
incineration.
11.2.8   Fire protection
          Conventional fire protection  systems are often  inappropriate
for central facilities in remote communities.  Unless a fire  is
controlled within seconds or minutes after it starts, there is  little
that can be done.   Partial measures  that can be  helpful are:   smoke
detectors, sprinkler heads or Halon  systems  for  critical  fire  hazard
areas, accessible and  clearly marked, and a  liberal  number  of
hand-operated  fire  extinguishers.
          Loud  sirens  or  alarms can  be  used  to  alert  the  entire  community
to  fire problems.
          Puchtler  et  al  [4] made  the  following  conclusion  on  fire
protection  for  central  facilities:

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                                   11-27
          "Providing  full  fire  protection  for  public  facilities in rural
          Alaska  is unusually difficult  and  expensive.   However,  since
          fire is a major  threat  to  facilities  in  cold  climate regions,
          a decision  not to  provide  this protection requires  careful
          consideration of resources  available  for replacement.  Insurance
          is generally not available  exeept  at  very high premiums."
          The ADEC has concluded  that the  level of fire protection
required by fire  codes designed  for  larger communities  in warmer  climates
is not practical  in the North.   Its  approach has been to provide  only
that level of protection which  is  convenient.   For example, water storage
tanks designed to meet the routine water supply needs for the central
facility can be used  to supply  sprinklers.   While  this  may not protect
the entire facility according to  fire codes, it makes the water that  is
stored available  for  fire  suppression at least  until  the water is gone.
Section 12 provides additional  detailed  information on  fire protection
for utilities in  the  cold  climate  regions.
11.2.9    Construction techniques
          In addition to choosing  the method of construction, the
designer must consider whether  to  use preassembled modular units,
prefabricated sections or  precut material  ready for assembly  at the job
site, or to "stick build"  the facility on-site.  Puohtler et  al [4]
concluded:
          "There  is no single best method  of constructing water-related
          utility facilities in rural Alaska.   Local  conditions,
          accessibility, etc.,  are so varied that  a limited number of
          standard designs could not  be  expected to effectively meet  the
          wide range of conditions."
The three basic options must be thoroughly analysed in  relation to each
specific project.
11.2.9.1  Modular.  Since  skilled  labor  in remote  communities is
generally unavailable, there are apparent advantages  to  using prebuilt
component modular construction, particularly for the  relatively complex
systems often found in central  facilities.

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                                  11-28
          Among these advantages are [7]:
          1)  components can be built more cheaply in the South where
              equipment can be installed and where preassembled modular
              units can be tested prior to shipment north, and
          2)  modular units can be more economically "mass" produced.
          The conceptual design for an environmental service module  by
Brown et al [1] stressed the importance of complete factory preassembly,
testing, and debugging of modular facilities prior to shipment and
installation at the site.  This is confirmed by the U.S. Environmental
Protection Agency which found, in its limited experience, that modular
construction was not very successful, due in large part  to inadequate
testing of component systems prior to shipment to the field [4],
          Another major consideration associated with modular
construction is the tendency to compact the equipment and service areas
in the modules to facilitate shipping and reduce structure costs.  As
stressed earlier, adequate space and accessibility to perform routine main-
tenance and equipment overhaul are essential, and crowded user space will
discourage use of even the most needed services in the central facility.
11.2.9.2  Prefabrication/precut.  Prefabricated buildings and component
pieces of equipment have frequently been used in remote  construction with
good results.  Advantages, compared with modular construction, include
ease of shipment and minimum wasted space (crowded conditions and
inaccessibility can be avoided), some flexibility to make minor changes
to meet field conditions, and operators have an opportunity to become
familiar with the central facility as it is being constructed.  Compared
with "stick-built" construction, assembly can be facilitated, fewer
skilled labourers are needed at the job site to assemble complex  systems,
and there is less waste of materials.  Preeut construction is similar  to
the prefabrication technique and shares many of the same advantages  and
disadvantages except that there are more "pieces" to assemble.
11.2.9.3  On-site fabrication.  The ADEC has had satisfactory experience
with conventional wood frame construction.  The main advantages are
simplicity of construction and ability to use local labour.  In addition,

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                                   11-29
 the operators  selected  for  the  facility  can  participate  fully in the
 construction from  the ground  up.   This helps  them  to  better  understand
 how the  facility operates and will  facilitate  operation  and  maintenance
 functions.  This technique  offers  the most flexibility to  modify designs
 to meet  field  conditions.   On the  other  hand,  complete on-site
 construction can take longer  and there will  be more waste  of materials
 than with the  other  techniques.
 11.1.10   Cost factors
          Table 11-4 shows  construction  and  operating  costs  for three
 central  facilities in Alaska.   They represent  facilities with minimum,
 average, and extensive  degrees  of complexity and levels  of service,
 respectively.
 TABLE  11-4.  CONSTRUCTION AND OPERATING  COSTS  FOR  THREE  CENTRAL FACILITIES
Community
Council , Ak
Pitkas Point, Ak
Nulato , Ak
Population
53
85
330
Year
Completed
1978
1976
1976
Capital
Construction
Cost
118 000
350 000
860 000
Annual
Operating
Budget 1977*
20 000**
60 400
85 700
*   Does not include amortization
**  Estimated
          The Council facility consists of a simple watering  point and
three outhouses located conveniently for the village.  The higher than  usual
construction costs can be attributed to the installation of a windmill  to
provide electrical power.  It is backed up with a small fuel  oil-fired
generator.  The well is about 65 feet deep and has no  treatment other than
provision for disinfection with chlorine.  The village selected this minimum
level of service because this was all they felt they could afford to
operate.
          The Piktas point central facility is considered to  be of average
complexity.  It provides a watering point, secondary sewage treatment,
showers, washers, dryers and saunas, and also water and sewer  service to a
school.  It was designed for simple operation, has several redundant

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                                  11-30
features to prevent freeze-ups, and was constructed using  the construction
management technique.
          Conventional competitive bidding was used for construction  of  the
Nulato facility.   It is a very complex system electrically and mechanically.
A high level of service is provided, including washers, dryers,  saunas,
tertiary sewage treatment, complex water  supply  treatment,  sewer and  water
service to a school, watering point showers, and  incinerator  for solid waste
and honeybucket waste disposal.
          Due  primarily to the fact that  water supply  and  wastewater
treatment requirements vary  so much among  the central  facilities, dependable
cost factors for  estimating  purposes cannot be established.  The cost
factors given  in  Section 2 may be used for general guidance,  with special
consideration  for specific water supply requirements and wastewater
treatment and  disposal needs.
11.3      Remote  Camps
11.3.1    History
          Remote  camps in  the  far North were used primarily to  support
military activities until  the  early  1960's.  These camps were used for
the military's DEW Line  stations spaced across the top of  North America,
and for oil and gas exploration activities in  the northwestern corner of
Alaska.  During the  1960's,  private  industry used remote camps  in their
search  for oil and gas in  the  North.   The early  camps  had  few amenities
for the workers and  living conditions  were crowded and often unsanitary.
They served up to about  50 people.
          With the discovery of commercial quantities  of oil and gas  at
Prudhoe Bay in 1968,  exploration activities virtually  exploded.   During
the summer of  1969,  a comprehensive  survey of  35 active camps and 30
inactive  sites on the north  slope was  conducted  [12].   The survey found
crowded living conditions, but  generally  good  dining  facilities.
Twenty-three  camps used  electric heat  and all  had some form of
pressurized water system.   Sewage was  almost  exclusively dumped on the
ground  or  into shallow pits  chipped  out  of the  permafrost.  Garbage was
generally  dumped  indiscriminately on the  ground  or into water bodies.

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                                   11-31
           For  all  camps,  the average consumption of water on a per person
basis  was  estimated  at 210 L/day.   Eighteen sources of water were from
rivers and seventeen were from tundra lakes.   Most of the camps consisted
of  prebuilt  modules  which were transportable  by Lockheed Hercules aircraft;
a few  were built on-site.
           Due  to concern  by government,  labour unions and environmental
groups,  industry has greatly improved remote  camps and minimized their
impact on  the  environment.   Housing is comfortable; dining facilities are
excellent;  recreational  facilities  are provided;  water is safe to drink;
various  types  of package  systems are available to treat sewage; and
combustible  garbage  and  sludges are incinerated prior to controlled land
disposal.   Recent  camps have housed from 10 to over 1500 persons.
11.3.2    Facility description
           Present  day camps in the  far North  are  generally quite similar
in  basic design and  configuration.   For  mobile camps, geophysical crews
(population  20 - 30)  use  prebuilt trailer modules on skids or tracks.
The  trailers each  serve a specific  purpose, including housing, dining,
clothes washing/laundry,  office, equipment/supply,  water supply, and
waste  treatment.   These trailers are particularly rugged and relatively
small  in size  (approximately 2.7 m  x 2.7 m  x  6.8  m).
           Semi-permanent  camp  configurations  and  facilities depend
primarily  on the number of  people served.   Modular  trailer units can  be
combined with  relative ease to meet specific  needs.  In the larger camps,
recreational facilities are added to  increase  worker  morale.   Typical
layouts for mobile camps  and  semi-permanent camps  are shown in Figures
11-9,  11-10, 11-11.   Permanent base  camps to  serve  between 150 and 300
people have been constructed  on-site,  and by  assembling complete
prefabricated modules  transported to  the site  by  barge  and large crawler
tractors.  Figure  11-9 shows one of  these facilities  located  at Prudhoe
Bay in Alaska.
          A large majority  of remote  camps in  cold  climates are
associated with the extraction and  transportation  to  market of oil and
gas reserves.  Table  11-5 shows the  types of  petroleum  industry related
camps,  populations served,  and duration.

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                       11-32
  FIGURE 11-9.   ROAD/PIPELINE  CONSTRUCTION  CAMP
FIGURE 11-10.  DRILLING RIG CAMP

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                                                     11-33
                 Access road
                                   Sewage treatmen
                                         Warehouse

                                    Warehouse
                                                                                Road to airstrip
                                              Valves and fittings enclose in insulated
                                              box with removable top     I  I

                                                   5 Day raw sewage 30 mil liner

                                                   Camp fuel supply 50,000 L diesel

                                       IIMIT   i	Sewage treatment

                                       ^y  :  t.	 Power plant

                                       '    I/I     56 Man housing (typical)

                                                  -52 Man hous
              52 Man housing (typical)

               Shop

               Shop

            Butler shop I    1

            Butler shopf~]

               Shop [^

                 Shop |     J
                                                                         age lift station
                                                                             ed)
                                                           ^-Office
                                                           First aid
                                                          Laundry
                                                        Recreation hall
Hydran

56 Man housing (typical)
                                            Equipment and material storage area
                                                                                       56 Man housing (typical)

                                                                                       52 Man housing (typical)
                                                                       S  Sewer
                                                                       W Water
                                                                       F  Fuel oil
                     250 000 L diesel emergency fuel supply
             900 Corrugated mela! pipe
             utihdor 14 guage
                                 100 Sewage line with 50
                                 nsulation field fit as required

                                 100 Waterlme with
                                 50 insulation
                                       General notes
                                       Indoors   A Sanitary sewers  all Sch 40 rigid P V C
                                                B Fuel oil all sizes black iron Sch 40 socket weld
                                                C Treated water all sizes copper

                                       Outdoors  A Sanitary sewers all sizes Sch 40 rigid PVC
                                                  pre-msulated with 50 urethane foam with heat tracing
                                                B Fuel oil as noted for  indoors
                                                C Treated water all sizes pre-insulated with
                                                  50 urethane foam and with heat tracing
                                                       Removable top
  ')0 Fuel oil
100 x 100 x 900 Wood
sleeper at 1200 centres .' '.

           Road Crossing
            Section  A-A
                                Handle
                                Lag bolts
              Gravel pad  ';'.'  '.'-.'.'
              Original ground level  ' 
                                 Alternative  Utilidor  Designs
                                                                                                 Section  B-B



n(o>(5)




                                                                               Alternative
                                                                           Walkway  Designs
      FIGURE  11-11.    LAYOUT  AND UTILITIES  FOR  A PIPELINE  CONSTRUCTION  CAMP

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                                  11-34
                 11-5.  REMOTE CAMP SIZES AND DURATIONS

Type of Camp	Population	Camp Duration	

Oilfield

     Exploratory              3-5                2-3 days
     Geological               20-30              3-7 days (winter)

Development
     Drilling                 50                   30 - 90 days
     Service                  50 - 100             Varies

Production
     Base                     150 - 300            20 years

Pipeline

Construction
     Road                     200 - 300            3-9 months
     Pipeline                 600 - 1000           3-9 months

Pump Station O&M	15	20 years
11.4      References
1.  Brown, C.K., et al, "Conceptual Design of an Environmental Service
      Module", Report No. 75-01 for Defense and Civil Institute of
      Environmental Medicine.  Ontario Research Foundation, July  1975.

2.  Dowl Engineers, "Design Narrative for Pitkas Point Village Safe Water
      Facility", for the Alaska Department of Environmental Conservation,
      Juneau, Alaska,  1975.

3.  Arctic Environmental Engineers, "Conceptual Design for Tanana, Alaska
      Facility", for the Alaska Department of Environmental Conservation,
      Juneau, Alaska,  1978.

4.  Puchtler, B. et al, "Water-Related Utilities for Small Communities in
      Rural Alaska".  Report No. EPA-600/3-76-104 (Ecological Research
      Series), U.S.  Environmental Protection Agency, Corvallis,  Oregon,
      1976.

5.  Cameron, J.J. and B. Armstrong, "Water and Energy:  Conservation
      Alternatives for the North", Presented at Symposium on Utilities
      Delivery in Northern Regions, March 19, 20, 21, 1979, Edmonton,
      Alberta, Environmental Protection Service, Ottawa, Ontario, (in
      preparation).

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                                  11-35
6.  Reid, Barry H., "Some Technical Aspects of the Alaska Village
      Demonstration Projects", IN:  Utilities Delivery in Arctic Regions,
      March 16, 17, 18, 1976, Edmonton, Alberta, Environmental
      Protection Service Report, EPS 3-WP-77-1, pp. 391-438, Ottawa,
      Ontario, 1977.

7.  Reid, Barry H. "Alaska Village Demonstration Projects:  First Generation
      of Integrated Utilities for Remote Communities".  Working Paper No.
      22, U.S. Environmental Protection Agency.  Arctic Environmental
      Research Laboratory, College, Alaska, 1973.

8.  Minuse Systems, Inc., "A New Way to Reduce Household Water Use by
      30%", Minuse Systems, Inc., 206 N. Man, Suite 300, Jackson, Calif.

9.  Schatzbert, P. et al, "Energy Conservation Through Water Resource
      Management - A Reduced Flow Bathing Shower", Second National
      Conference on Water Reuse:  Water's Interface with Energy, Air and
      Solids,  Chicago, May 4-8,  1975.

10.  Bailey, J.R. et al, "A Study of Flow Reduction and Treatment of
      Waste Water from Households".  Water Pollution Control Research
      Series 11050 FKE, Dept. of Health, Education and Welfare,
      Washington, D.C., 1969.

11.  Aulenback, D.B. et al, "Treatment of Laundromat Wastes", Report No.
      EPA-R2-73-108 (Environmental Protection Technology Series), U.S.
      Environmental Protection Agency, Washington, D.C., 1973.

12.  Alaska Department of Health and Welfare, Federal Water Pollution
      Control  Administration, Arctic Health Center, "The Influence of Oil
      and Exploration and Development of Environmental Health and QualityM
      on the Alaska North Slope", Fairbanks, Alaska, December 1969.
11.5      Bibliography

    Anon,  "Waste Disposal Systems for Polar Camps".  Technical Note
      N-377,  U.S.  Naval Civil Engineering Laboratory, Port Hueneme, Calif.,
      November 1959.

    Anon,  "Review of  Polar Camp Sanitation Problems and Approach to
      Development  of  Satisfactory Equipment for a Polar Region 100 Man
      Camp".   Technical Note N-032,  U.S.  Naval Civil Engineering
      Laboratory,  Port Hueneme, Calif.,  August 1952.

    Given  P.W. and H.G. Chambers, "Workcamp Sewage Disposal, Washcar -
      Incinerator  Complex, Ft.  Simpson,  NWT",  IN:  Some Problems of
      Solid  and Liquid Waste Disposal in  the  Northern Environment,
      J.W.  Slupsky [ed],  Environmental Protection Service, Northwest
      Region,  Edmonton, Alberta,  EPS-4-NW-76-2, pp. 1-42,  1976.

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                            11-36
Mecklinger, Sheldon, "Servicing of Arctic Work  Camps".  Department
    of Civil Engineering, University of Toronto,  Toronto,  Canada,
    April 1977.

Nehlsen, W.R., "A Development Program for Polar Camp Sanitation",
    Technical Note 476, Armed Forces Technical  Information Agency,
    U.S. Naval Civil Engineering laboratory, Port Hueneme, Calif.,
    December 1962.

Sargent, J.W. and J.W. Scribner, "Village Safe Water Project  in
    Alaska - Case Studies".  Alaska Department  of Environmental
    Conservation, March 1976.

Sherwood, G.E., "Specifications for a 25-Man Pioneer Polar Camp".
    Technical Note N500, U.S. Naval Civil Engineering Laboratory,
    Port Hueneme, Calif., 1963.

U.S. Defense Documentation Center, "Temporary Polar Camp  Concept and
    Design Criteria".  Technical Note N-436, Virgina, March,  1964.

U.S. Environmental Protection Agency, "Alaska Village Demonstration
    Projects".  Report to the Congress, Washington, D.C.,  July
    1973.

U.S. Naval Civil Engineering Laboratory, "A Temporary Polar Camp".
    Technical Note R 288, Port Hueneme, Calif., March  1964.

U.S. Naval Civil Engineering Laboratory, "Self  Contained  Sanitation
    Systems for 2 to 15 Man Polar Facilities".  Technical  Report
    R759, Port Hueneme, Calif, March  1972.

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                               SECTION 12
                             FIRE PROTECTION
                                  Index
12       FIRE PROTECTION                                            12-1
12.1     General                                                    12-1
12.2     Administration of Fire Protection Standards                12-1
12.3     Codes and Guidelines                                       12-2
12.4     Fire Prevention Criteria                                   12-2
12.4.1   General                                                    12-2
12.4.2   Water supply fire protection requirements                  12-3
12.5     Equipment                                                  12-3
12.5.1   Trucks                                                     12-3
12.5.2   Other methods                                              12-7
12.6     Community Fire Alarm Systems                               12-8
12.6.1   General system description                                 12-8
12.6.2   System operation                                           12-9
12.6.3   System components                                          12-10
12.6.4   Alternate system design                                    12-12
12.6.5   Cost                                                       12-13

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                             List of Figures




Figure                                                              Page




12-1     Graphic Annunciator Panel Detail                           12-11
                               List of Tables




Table                                                               Page




12-1     Fire Protection Guidelines for Water Supply                12-4

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                                 12-1
12       FIRE PROTECTION
12.1     General
         Fire prevention, fire alarm and warning systems, and methods of
combatting fire in isolated northern communities present unique problems
that cannot be practically resolved by superimposing southern fire codes
and prevention standards.
         The high cost of construction; the harsh climatic conditions
(very low ambient temperatures, generally extreme winds, drifting and
blowing snow); low population densities (most communities under 1000 in
population, almost all with volunteer fire departments); the very long
heating season; the dryness of materials and air; the generally poor
community infrastructures, i.e., rough gravel roads, no piped water in
most communities, little or no telephone service, are all factors which
make it difficult to guard against and fight fires in cold regions.
         The proposed design guidelines for fire protection given in this
section are the result of experience and methods developed in the
Northwest Territories, Canada, since 1970.  Techniques and methods used
in Alaska and Greenland are also noted.
12.2     Administration of Fire Prevention Standards
         The following is a list of the governing authorities for fire
prevention standards.  In other northern regions or jurisdictions, local
regulatory authorities should be consulted.
LOCATION                  ACT (If applicable)          AUTHORITY
Northwest                 Fire Prevention              N.W.T. Fire
Territories,              Ordinance                    Marshal, Government
Canada                                                 of the N.W.T.,
                                                       Yellowknife, N.W.T.,
Yukon Territory,                                       Yukon Fire Marshal,
Canada                                                 Government of the
                                                       Yukon, Whitehorse,
                                                       Yukon
Alaska,                                                State Fire
U.S.                                                   Marshal's Office,
                                                       Dept. of Public
                                                       Safety, Juneau,
                                                       Alaska 99811

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                                 12-2
12.3     Codes and Guidelines
         Codes with respect  to  building  spacing  and  water requirements
for fire protection purposes vary with  the  location  and  governing
authorities.
         The main codes  in use  in temperate climates are:
         - National Board of Fire Underwriters,
         - National Fire Code,
         - Uniform Fire  Code, Insurance  Advisory Organization,
         - National Building Code.
         Some of the guidelines are not  practical or applicable for
small northern communities and  must be  constantly adapted or altered to
meet specific conditions under  approval  of  the authority having
jurisdiction.
         Two sets of guidelines for water flow and storage requirements
are given in Appendix  I.  Appendix I.I  gives  a draft standard for water
supplies for small rural isolated communities (such  as Indian reserves
throughout the various provinces of Canada)  prepared by  the Canadian
Dominion Fire Commissioner's office.  Appendix 1.2 gives a guideline for
water works design, prepared by the Province  of  Ontario.
12.4     Fire Prevention Criteria
12.4.1   General
         Fire prevention criteria, such  as  building  spacing, building
location distances from  roadways, access to buildings, fire escapes,
building occupancy, requirements for  sprinklers  and  smoke detectors and
requirements for water distribution system  flow  and  storage capacity in
the North, are generally adopted from existing codes,  such as the
Building Codes and Fire  Codes referred  to previously,  and as formulated
by the authority having  jurisdiction.
         Although the  purpose of fire protection systems is universal,
the capability of water  supply  and distribution  systems  to meet the rigid
requirements of codes  cannot always be  provided  in small rural  communi-
ties.  Economic and physical constraints have dictated the limits of
water supply and distribution systems,  which  in  turn may prohibit meeting

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                                 12-3
present codes and guidelines  for  fire  protection.   In  such  cases,  the  best
practicable fire protection system developed  often  employs  alternatives  to
water for fighting fires.  Also,  when  a  fire  is  extinguished  with  water  at
below 0C temperatures  the resulting iee can  do  more damage to  the
building than the fire.
         There are numerous communities  in both  Alaska and  northern
Canada where there are  no funds for necessary infrastructures,  such as all
weather roads to allow  a fire  truck to operate,  let alone funding  for  the
purchase of a fire truek.  Despite the above,  assuming communities are to
be viable entities and  fire protection treated seriously, the reoommenda-
ations made in this section are considered to  be the achievable, practical,
minimum level to be strived for.
12.4.2   Water supply fire protection  requirements
         General assumptions  used when determining  water supply values
required for fire fighting are as follows:
         - The water supply fire  protection requirements are  considered
           concurrently with  the  total community utility development
           planning.  For instance, an indoor  swimming pool can be also
           used to satisfy community fire storage capacity.
         - Population is based on a 20-year forecast.
         - Each community has  its own  unique  set of characteristies.
           Population levels  used to determine the  standard of  fire
           protection which should be  provided will depend  on a detailed
           economic analysis.  The choice between a trucked or  small
           piped or large piped system will be based on an  economic
           evaluation over the 20-year forecast  period.
         The guidelines for water supplies in  northern communities
recommended in Table 12-1 are based on Appendix  I and  experience gained
in Alaska and northern  Canada.
12.5     Equipment
12.5.1   Trucks
         Communities of less  than 150 in population.   The water truck  can be
         used as the fire truck.  See Section  6  for description and cost.

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                         TABLE 12-1.  FIRE  PROTECTION  GUIDELINES  FOR WATER SUPPLY
 TYPE OF
 SERVICE
   COMMUNITY CHARACTERISTICS
  FIRE  PROTECTION WATER  DELIVERY
        SYSTEM  REQUIREMENTS
 Trucked
 Water
 Delivery
- Trucked water supply only.

- Bldg. spacing 12 m (minimum)

- Community fire alarm system
  in operation.

- Volunteer fire brigade.
Community water  point must  be  capable
of delivering  a  minimum  of  450 litres/
minute.

Fire  truck/pumper  is left with full
tank  in heated garage.

Domestic water truck is  left full  in
heated garage  as back up.
Small
Diameter
Piped System
- Small diameter piped system (flow
  based on consumption requirements
  only).

- Hydrants can be provided to
  allow limited access to water
  for fire fighting.

- Building spacing 12 m (minimum).

- Community fire alarm system in
  operation.

- Volunteer fire brigade.
Water storage  tank for  fire  fighting
purposes to be  supplied  and  located  in
central or strategic location  in  the
community.  Size of storage  capacity  to
be based on the formula  described  in
Appendix G.

Piping capacity of a minimum of 2500
litres/minute  either from a  truck  mounted
pump or insitu  pump that will  deliver water
directly from  the storage tank through an
appropriate hose delivery system  capable of
servicing a 150 m radius from  the  storage
tank.

A truck water  point from the storage  tank
location will  be provided capable  of delivering
700 litres/minute for refilling the fire
truck to combat fires in those areas not
capable of being reached directly  by hose.

All available  fire and water delivery trucks
to be kept in heated garages at all times.
N3
i

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TABLE 12-1.  (CONT'D)
 Large
 Diameter
 Piped Core
 System
- Large diameter core system with
  hydrants.

- Remainder of community serviced
  by small diameter piped system
  with no fire flow provisions.

- Building spacing core area with
  hydrant coverage 3 m (minimum).

- Building spacing elsewhere 12 m
  (minimum).

- Community fire alarm system in
  operation.

- Volunteer fire brigade.
Water storage tank for fire fighting
purposes to be supplied and located in  the
community.  Size of storage capacity  to
be based on the formula described  in
Appendix G.

Pumping capacity of a minimum of  2500
litres/minute either from a truck  mounted
pump or insitu pump that will deliver
water directly from the storage tank
through an appropriate hose delivery
system capable of servicing a 150  m
radius from the storage tank.

All hydrants on large diameter core system
to be capable of providing 2500 litres/minute
through either an in place pumping system
or truck mounted pumps.  Each hydrant
should service a circular area with a
radius of 70 m.

A truck water point from the storage  tank
location will be provided capable  of
providing 700 litres per minute for refilling
of fire truck to combat fires in  those
areas not capable of being reached directly
by hose.
                                                                                                               NJ
                                                                                                               i
                                                                                                               Ul
 Large Diameter
 Piped System
 Throughout
 Community
- Larger diameter piped system,
  i.e. minimum pipe size 150 mm or
  greater.  All lines with hydrants
  in place every 70 m or less and
  capable of producing required
Storage tank capacity as  per  formula
given in Appendix G.

Water fire flow capacity  as
outlined in Appendix G.

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TABLE 12-1.  (CONT'D)
 (cont1d)
- Building spacing minimum 3 m or
  as specified by the appropriate
  authority.

- Community fire alarm system in
  operation.

- Paid fire chief.

- Volunteer fire brigade.
- Fire flow capacity can be provided
  through in place pumping system  or  truck
  pump.
                                                                                                              Isi
                                                                                                              I

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                                  12-7
         Houses  should  be  equipped with cartridge  fire  extinguishers  and
         detectors.
         Communities with  no  piped water.
         A 4500-L capacity truck  should be  provided with  a  2800  L/minute
         pump output rating.
         Truok cost including  assessories   $  50  000
         Fireball cost  (one bay)            $100  OOP  ($500/m2)
         Communities with  small diameter piped water, no  hydrants.
         Same as above.
         Communities with  large diameter piped water, with  hydrants.
         A 2273-L capacity truck  should be  provided with  a  3800  L/minute
         pump output rating,  to be used in  conjunction  with hydrant or
         storage tank  facility.
         Truck cost including  accessories   $  60  000
         Fireball cost  (one bay)            $100  OOP  ($500/m2)
12.5.2   Other methods
         Foam equipment, either cylinder or truck-mounted,  is  not
recommended for northern use  during  low ambient  temperatures of  -25C
or eolder.  Such cold  temperatures do not allow  the aspirator  to mix
properly with the foam; a  "soup"  is  produced.
         Dry chemical.  Large  350-lb  ABC dry chemical extinguishers have
been used in most communities  in  the Northwest Territories,  Canada, with
satisfactory results when  properly utilized.  Because of  the large size
of the unit, it is difficult  to move in a hurry  and should  really be
incorporated in a truck kept  in a heated garage  and ready to go.  In
those communities where it  is  best utilized,  the unit is  placed  on a
stand ready to be rolled onto  a half ton truck or  dump  truck and taken to
the fire.  The unit must be serviced after  each  use.
         Halon gas is useful  in high hazard buildings and where
electrical or mechanical equipment could be destroyed by  wet system
malfunction.  This system  is expensive and  is not  applicable in  all
buildings at this time.

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                                     12-8
          Fire extinguishers for house use are recommended and should be
the cartridge dry chemical ABC type.   These have proven the most reliable
and most economical to maintain.  Commercially available units of various
sizes have fusible links which automatically discharge when exposed to
fire.
          Smoke detectors are usually actived by sensing the products of
combusiton.  Such units may be installed in kitchens or next to furnaces.
They are becoming more prevalent and in some cases are mandatory.  All
public government buildings and staff houses in the Northwest Territories,
for instance, must have a permanently wired smoke or heat detector devices.
          There are anumber of smoke detectors on the market, and as long
as the unit has been approved by the Canadian Standards Association (CSA)
and Underwriters' Laboratory (ULC) it will do a satisfactory job when
used in accordance with the manufacturer's direections.
12.6      Community Fire Alarm Systems
          Community fire alarm systems in the North, while highly desired
by the communities, have been an extreme source of frustration for users,
maintainers and designers over the years.  A system is a failure unless
it works when it is needed and works every time.  Considering the factors
of climate, lack of technically competent tradesment, constant turnover  in
personnel, et., a perfect operational record is a monumental achievement
for a designer who must also produce an economical system.
          The community fire alarm systems described in this section were
delveoped by Mr. Ray Stoodley of the Government of the Northwest
Territories, based on previous  experience and personal knowledge of
northern  conditions gaind over  the past two decades as an  electrical
contractor, and  in his present  position with the Government  of the
Northwest Territories.
           It  is  essential to  involve the  local people  in the design and
installation process to the point where they see the merit of  regular
checks  and any preventative maintenance required.
12.6.1     General  system  description
           The previously  adopted  southern systems  used  standard  drop  zone
annunciator panels  (8-12  zones) and 1 hp  single-phase  repulsion  induction

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                                 12-9
motorized sirens.   The  present  state-of-the-art  in  the  North employs
supervised multi-zone annunciator  solid  state  equipment and  leased
telephone company  cable pairs for  call box  signal and multi-siren
activation.
12.6.2   System operation
         Call boxes are located  strategically  throughout the community to
provide maximum coverage.   In the  event  of  a fire the call  box button is
pushed, which sets  off  the  sirens  and  thus  marshalls  the volunteer fire-
fighters at the fire hall.  At  the same  time,  a  graphic readout annuncia-
tor panel is activated  at the fire hall.  In other  words, a  red light on
a large scale map  of the community shows  the location of the tripped pull
box.  The firemen  note  the  location and  proceed  to  the  fire.  The sirens
continue until the  annunciator  panel alarm  light is acknowledged by the
arriving firemen.   If in the interim another call box has been tripped,
it will light up after  the  first light has  been  acknowledged and again
set off the alarm.  The system  is  constantly supervising itself, which
means that a short  in a cable pair or  a  severed  line will sound a trouble
alarm altering the  appropriate  staff to  the problem.
         A test button  is provided, which by-passes the timing circuit
and allows control  of the siren  for up to two  minutes,  at the discretion
of the operator.   (Two  minutes  is  the maximum  recommended time to operate
these sirens.)
         The system can aoeept  signals such as low  temperature, intrusion
or any other dry contact, by simply adding  the required annunciation and
audible devices separately  from  the  siren circuit.  This allows the      ,
system to be integrated with other critical community utilities suoh as
water supply, etc., since in most  small  communities the diesel-generated
power is unreliable.  Under and  over voltage protection is  provided by a
voltage limiter, whieh  will disconnect the  supply voltage when it drops
to 105 volts AC and pick up again  at 120  volts AC.  A time delay of two
to five seconds is  fitted to prevent relay  chatter.  Disconnection of the
system is preferred to  a previously designed battery powered system which
used AC power for charging-up as required.  Even with battery standby

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                                 12-10
provision, no power would be available during a power outage  for  siren
operation; therefore, standby battery power is really superfluous.  The
system is fitted with a program clock device to sound a daily curfew for
a predetermined time (constant blast of approximately 20 seconds).  This
also provides daily testing of the sirens.
12.6.3   System components
         Sirens may be electronic or rotary multidirectional.  Electronic
sirens are used in smaller settlements with populations of 350 or less
and restricted to a maximum community distance in any direction of  3 km.
         Characteristies of this type are:
         - low capital costs ($130 each);
         - minimum or no maintenance;
         - coverage of 110 DB @ 3 m in still air;
         - uses 120 volt AC;
         - lightweight (one man can change a defective unit);
         - daily testing required to prevent heavy ice build-up.
         Rotary multidirectional sirens are more cost-effective for
larger communities.  In general, where adequate coverage for  a community
requires 12 or more electronic sirens then one or two rotary
multidirectional sirens are used.
         Characteristics of this system are:
         - 5 hp three-phase, 208 volts, high horse power required to
           ensure any ice build-up is sheared away on start-up;
         - thermistor sensors in motor winding wired with normal motor
           overload circuit to prevent burn out;
         - life expectancy of 20 years;
         - coverage of 115 DB @ 30 m with an effective sound  range  in
           still air of 1050 m.
         - cost of $2500 each.
         Leased telephone cable pairs are preferred  to individually
installed and maintained cable plants for signal circuits because of
lower capital and maintenance costs.

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                                  12-11
         Graphic readout  panels  in  the  fire  halls  display all station
call boxes with indicating  lamps superimposed  on a large-scale plasticized
map of the community  (see Figure 12-1).   Also  included  are acknowledge,
reset and trouble  lights, and  test  buttons.  The panel  must be tailor
made but eliminates any confusion as  to  where  to go in  situations where
firefighters are made up  of people  with  different  languages.
                  FIGURE  12-1.   GRAPHIC  ANNUNCIATOR
                                 PANEL  DETAIL
         Station indicating lamp  call  box assembly.   Based  on
experience and past  problems,  the best  call  box  for  northern use  is a
CEMA-3 enclosure of  special design  to  prevent  entry  of  rain, sleet or
driving snow.  On opening  the  enclosure door,  the  caller  merely pushes
the red button for a moment.   Behind the facia holding  this  push  button
is a pair of line fuses.   One  spare fuse provides  protection for  the
station indicating lamp circuit.  The  indicating lamp used  is rated at  60
watts, 8000 hours for long life and low maintenance.  All related wiring
between the indicating lamp higher up  the utility  pole  and  the call box

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                                 12-12
is eontained in a rigid PVC conduit.  The rigid PVC results  in  a  good,
water-tight, noncorrosive and very easy field installation.   Each call
box is grounded at the base of the PVC.  Where permafrost  or soil
conditions prevent the use of ground rods, a grounding mat buried a
minimum of 60 cm for a length of 16 m is used.
         Solid state relay equipment operates at between 5 and  35 volts
DC and is capable of switching an AC load of up to 16 amperes.  The relay
is completely sealed and has an expected life of 20 years.  Unlike
previous designs, the solid state relays do not require matching  relays
on call box circuits located up to 8 km away from  the main control
system.  Problems with end of line resistors or diodes are also
eliminated since the new configuration does not require these components.
Lightning surges and possible stray currents to call  circuits are
prevented by the telephone company lightning arrestor equipment.
12.6.4   Alternate system design
         A system has been installed and is operating in Cape Dorset
(population approximately 900) which is based on the  use of  a Bell Canada
type 700 "Code-A-Phone" device.  This device replaces both the  solid
state relay equipment and the graphic read-out panel.  All other
components, i.e., call boxes, sirens, etc., remain the same. Using a
pre-coded number (e.g. 2222), any telephone in the community is able to
set off the fire sirens.  At the same time, a prerecorded  message will
ask in whatever language applicable, "Where is the fire?".  The caller
can then give  the name and location.  The firemen  responding would play
back the tape  to ascertain the caller's identification and location.
         ADVANTAGES:     - very low installation cost (40% of a standard
                           system);
                         - assuming 80% telephone  coverage,  increased
                           safety factory by virtue  of  quicker  alarm
                           activation;
                         - minimal maintenance;
                         - system will  easily adapt  to  any number of
                           sirens.

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                                 12-13
         DISADVANTAGES:  - possible false alarms;
                         - possible confusion when  the  caller  tries  to
                           tape the information;
                         - forgetting  to reset  the  tape  (although good
                           for 12 hours it would be desireable to have
                           the unit reset itself after  each  call  has been
                           acknowledged);
                         - cannot easily be  tied in to  equipment  for
                           other alarms, e.g.,  water  flow, etc.
12.6.5   Cost
         The average cost per signal circuit pair per month  is $3.50.
Between 12-36 pairs will be needed, depending on the  size of the
settlement.  The average coverage per  call box  is one for every five
homes or 30 people.  Major buildings and installations  must  be considered
separately.  The installed cost of these systems is approximately
$1 000 per call station.  This includes the  cost of siren and  annunciator
equipment.
         The cable cost would be additional  to  the  above figure and
varies considerably between the western and  eastern territories.
Examples are Rankin Inlet, where the installed  cable  cost for  36  pairs
was $2 300 and Fort Resolute, where the cable cost  for  26 pairs was
$8 300.  Line pair rentals run approximately 50% lower  in the  east and
central, compared with the western territories.

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                                 SECTION 13
                           SOLID WASTE MANAGEMENT
                                  Index
13       SOLID WASTE MANAGEMENT                                      13-1
13.1     General                                                     13-1
13.2     Municipal Solid Wastes                                      13-2
13.2.1   Quantity and composition of wastes                          13-2
13.2.2   Household storage and collection                            13-3
13.2.3   Disposal methods                                            13-7
13.3     Industrial and Special Solid Wastes                         13-20
13.4     Human Wastes from Households and Establishments             13-21
13.4.1   Storage at the house and collection                         13-22
13.4.2   Quantity and composition of human wastes                    13-27
13.4.3   Disposal                                                    13-27
13.4.4   Costs and Charges                                           13-30
13.5     References                                                  13-32

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                             List of Figures
Figure                                                               Page
13-1     Garbage Collection                                          13-6
13-2     Garbage Barrels on Raised Wooden Platforms                  13-6
13-3     A Poor Example of Garbage Storage at the Home               13-8
13-4     Garbage Cart and Stand                                      13-8
13-5     A Difficult Solid Waste Handling Problem                    13-12
13-6     A Proper Garbage Dump Truck would Help Considerably         13-12
13-7     Attempt to Create a Dumping Slope on Flat Terrain  (a)       13-13
13-8     Attempt to Create a Dumping Slope on Flat Terrain  (b)       13-13
13-9     How would You Like This Job?                                13-14
13-10    Disposal of Garbage and Honeybags at the Same  Site.
         This should not be done                                     13-15
13-11    Storage Tank Disposal on Garbage Dump                       13-15
13-12    Typical Bucket Toilet                                       13-23
13-13    Manual Handling of Honeybags Stored in Drums in  Front
         of the House until Collection                               13-24
13-14    Metal Buckets Used for Collection of Human Waste           13-25
13-15    Rear View of Honeybag Suction Vehicle                       13-26
15-16    Disposal Station for Human Waste at Egedesminde,
         Greenland                                                   13-31
13-17    View of Inside of Disposal Station, Egedesminde,
         Greenland                                                   13-31
                               List of Tables
Table
13-1     Quantities of  Solid Waste from  Camps
13-2     Quantities of  Solid Waste from  Communities
13-3     Composition of Solid Wastes
13-4     Domestic Refuse  Composition  for a Typical Aretic
         Community
13-5     Garbage Collection Costs
13-6     Characteristics  of Human Waste  (Honeybags)
13-7     Honeybag Collection Costs
13-2
13-3
13-4

13-4
13-19
13-28
13-30

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                                  13-1
13       SOLID WASTE MANAGEMENT
13.1     General
         Solid wastes are one of  the most  important  visual  parts  of an
overall sanitation program for northern communities.   Many  priorities
must be met with limited funds by those charged with the  responsibility
to provide for and improve social and environmental  conditions  in
these communities.  Providing jobs, housing,  heat, light, water and
sewage disposal have been given higher priority than solid  waste
management in the past, but  it has recently  received greater  attention.
Emerging legislation, research and pilot projects  for solid waste
management are evidence of increasing concern.
         For the purpose of  this  manual, solid wastes are divided into
three groups:
         - municipal solid wastes:  from households,  commercial or
           institutional establishments;
         - industrial and special wastes;
         - human wastes from households and  establishments.
         The disposal of sludges  from water  and wastewater  treatment
plants is covered in Section 10.   The disposal of  human wastes  without
water carriage occurs because of  the lack  of  piped water  and  sewer
systems in many of the smaller communities.   Because of the similarities
in the storage, collection and disposal of garbage/refuse and human
waste, the latter is discussed in this section, with reference  made to
other sections where relevant.
         The objectives of solid  waste management, north  or south, must
be to dispose of wastes without creating hazards,  nuisances,  or aesthetic
blights for people and for the environment,  and to achieve  this in the
most economical manner for a given situation.  To  achieve these
objectives, it is necessary  that  each component of the solid  waste
management system, namely, storage in or at  the house, collection and
treatment/disposal, is properly carried out.  Reviews of  northern
practices in solid waste management with recommendations  for  improvements
have been carried out by a number of agencies [1-8,19,30,33],

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                                 13-2
13.2     Municipal Solid Wastes
         Municipal solid wastes include all unwanted or discarded  solid
or semi-solid material from households, commercial and institutional
establishments.  While the type and quantity of wastes from these  will be
similar to those in southern communities, there are special considera-
tions to be taken into account in northern communities.  Most of the
'goods' consumed must be shipped from the South.  This leads to greater
quantities of packaging material in the waste.  The isolation and  high
transportation costs make recycling of used machinery, mobile homes,
automobiles, etc., as scrap raw material uneconomical and increase  the
quantities to be disposed of locally.  Finally the combination of  past
social customs, inadequate health and sanitation habits and education
make it difficult to implement effective solid waste management.
13.2.1   Quantity and composition of wastes
         Data on refuse from work camps, military bases and airport
facilities, which in many aspects are similar to southern communities,
are shown in Table 13-1.
            TABLE 13-1.  QUANTITIES OF SOLID WASTE FROM CAMPS

   Camp                                              Quantities

Air Force Base [10]                                 2.3 kg/person/day
Pipeline Construction Camps [11]                    2.7 kg/person/day
Alaska-Federal Facilities [5]                       2.7 kg/person/day
Fort Greely [5,15]                                  6.1 kg/person/day
         Recently Wardrop ^t al^  [37] reported that facilities  such as
these in the Northwest Territories generated refuse at a  rate  of  2.7 to
4.4 kg/person/day.  The Alaska Department of Environmental Conservation
(ADEC) uses a generation rate of 3.6 kg/person/day for design  purposes.
         Little information regarding the density of refuse  from  such
facilities is available.  However, a recent survey at Alert, N.W.T., made

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                                      13-3
by Wardrop et al  [37]  concluded that the refuse generated at this site
had  a  density of  91 kg/m3.
          Table 13-2 tabulates orae recent information on solid waste
quantities for communities with little industrial activity.

            TABLE 13-2.  QUANTITIES OF SOLID WASTE FROM COMMUNITIES
          Camp                               Quantities

Tuktoyaktuk, N.W.T. [9]            0.014 m3/person/day (0.5 ft3/person/day)
Alaska  [5]                         2.8 kg/person/day
  (average of communities > 500)   0.015 m3/person day (0.54 fts/person/day)
Northern ONtario  connumities  [12]  0.005 ms/person/day (0.18 ft3/person/day)

          For such communities, an average volume of about 0.005-1.015 m3
should be used for planning purposes.  The lower figure would apply when
burning at the household or establishment is practised.   Without special
compaction or burning the average density may be about 130 kg/m3 but
considerable variation must be expected.   On a weight basis, therefore,
1.8 kg/person/day can be used for design purposes.
          Tables 13-3 and 13-4 provide the only available information on
compostion of solid waste in residential communities.  Table 13-3 reports
a survey of two northern communities, Juneau and Anchorage, and provides a
compparison with a southern community,  Madison, Wisconsin,  and the U.S.
national average.   It should be noted that both Juneau and Anchorage are
larger, more temperate zone communities than many other norther communities.
          Table 13-4,  on the other hand,  provides an estimate of domestic
refuse composition for typical northern communities which may be helpful in
small community design.  This information is based on unpublished data
collected by W.L.  Wardrop and Associates  Ltd.  personnel  during visits to
several Arctic communities.
13.2.2    Household storage and collection
          In the larger communities the practice of storage and collection
of waste does not  differ substantially  from the practices in southern
communities.   In smaller northern communities  garbage and refuse are

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                                 13-4
               TABLE 13-3.  COMPOSITION OF SOLID WASTES
Classification
                                 Percent of Total Sample

Food Waste
Paper Products
Plastics
Rubber and Leather
Textiles
Wood
Metals
Glass and Ceramics
Garden Waste
Inerts (dirt)
Totals
Juneau,
Alaska
15.2
45.8
4.0
1.3
3.0
0.6
12.5
17.1

0.4
99.9
Anchorage,
Alaska
15.2
43.7
4.1
0.9
2.1
1.2
10.0
14.5
6.5
1.7
99.0
Madison,
Wisconsin
15.3
42.4
1.8

1.6
1.1
6.7
10.1
13.8
7.2
100.0
U.S. National
Average
17.6
31.3
6.0

1.4
3.7
9.5
9.7
19.3
1.4
100.0
TABLE 13-4.  DOMESTIC REFUSE COMPOSITION FOR A TYPICAL ARCTIC COMMUNITY
Component
Composition by Weight
Combustibles (wood, paper, etc.)
Metal
Organic Wastes
Moisture
        50%
        15%
        15%
        20%

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                                  13-5
commonly  stored  at  the  house  in  readily available oil drums.  They are
probably  the  only  type  of  container capable of sustaining the abuse by
weather,  people  and animals.   They are large enough to hold animal
carcasses and other bulky  refuse and heavy enough not be be upset by wind
or dogs.  Also,  one can burn  combustible waste in them for volume
reduction.  This practice  should be encouraged.   They are, however,
difficult to  lift manually onto  the collection vehicle (Figure 13-1).
Mechanical  lifts can be attached to the side of  the collection truck to
avoid this  problem.   In some  communities raised  wooden platforms have
been constructed to hold drums for garbage and honey bags so that they
can be easily emptied (Figure 13-2).   In many instances this attempt has
been a failure,  either  because the platforms were not rugged enough, or
they became an eyesore  since  they were covered much of the time with
spillage.   This  eventually caused them to be abandoned.  In other
communities smaller metal  or  plastic pails are used.  They are easier to
handle, but are  blown over by wind or upset by dogs, do not hold bulky
waste, and  burning  cannot  be  practised.  Plastic containers are also
brittle at  low temperatures.   In all containers  garbage will freeze to
the walls, making it difficult to empty them in  cold weather.  A pilot
study program using paper  sacks  was carried out  by Environment Canada in
two northern  Canadian communities.   The results  were disappointing; the
project had to be abandoned soon after its start, since the local
population  did not  perceive it as an improvement over previously used
methods [29],  In summary,  there is much to recommend the continuation of
the use of  the readily  available oil  drums for storage at the house, but
it also should be coupled  with educational efforts to avoid the situa-
tions shown in Figure 13-3.   Periodic cleaning and painting of drums is
recommended.
         In many communities  there  is some organized collection of
garbage and refuse  on a weekly or twice-weekly basis.  Mandatory or
universal collection is  currently required in more than 50% of Alaskan
communities greater  than 500  people [5],   In all but the very small
communities weekly  collection, whether public or private,  should be
required.  Garbage  and  refuse  collection should  be separate from the
collection of  bagged toilet waste,  since the latter requires daily

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                    13-6
FIGURE 13-1.  GARBAGE COLLECTION

FIGURE 13-2.  GARBAGE BARRELS ON RAISED
              WOODEN PLATFORMS

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                                  13-7
 frequency and  a separate disposal site.   Vehicles vary in sophistication
 from  the  garbage packer truck as used in the south to tractor-drawn open
 carts (Figure  13-4).   Most vehicles are  of the open type and lose garbage
 within the community  and along the road  to the dump.  This sets a bad
 example  to the people and negates any educational efforts for cleanup.
 Enclosed  or covered vehicles should be required with the appropriate
 degree of sophistication depending on the size of the community.
          Garbage crews should also be made responsible for general street
 cleanup and maintenance, and thus set an example to the citizen.  Without
 this,  the appearance  of many northern communities suffers from the
 indisoriminate disposal of garbage, refuse,  vehicles and scrap items of
 all sorts in yards, on roads and beaches.  This becomes progressively
 worse  as  the winter goes on, mercifully  covered snow.  Massive spring
 cleanups  occur in most communities.  Community-wide cleanups should be a
 general practice several times a year and their need particularly
 impressed upon the  young in school.
 13.2.3   Disposal methods
          Alternatives for disposal of solid  wastes in northern communi-
 ties and  eamps  include:
          1)  open dump/landfill;
          2)  modified landfill;
          3)  ocean  disposal;
          4)  incineration;
          5)  milling  and compaction;
          6)  recycling and  reuse  (haulback).
 Currently the  most  often used  method  is  the  open  dump,  which in some
 cases  can  be termed a modified  landfill.   Seventy-six percent of Alaskan
 communities  use  a form of open  dump/landfill method,  13% use ocean
 disposal  and 11% employ  incineration  (all of these are  U.S.  federal
 facilities  [5]).  The  open  dump/landfill  is  also  widely used in Canadian
 communities.   The advantages and  disadvantages  of each  method are
discussed  below.

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co
 i

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                                  13-9
 13.2.3.1  Open  dump/landfill.   The  main reasons for the use of the open
 dump  are  its simplicity of operation,  its  low cost, and the lack of
 suitable  alternatives.   The main arguments against its continued use are
 the many  instances  of  complete disregard of even the most simple techni-
 ques  of discrimination in the  selection and operation of existing
 disposal  sites.   These  poor practices, which are avoidable, make it
 difficult  to convince  regulatory authorities and the public to accept the
 open  dump/landfill.
          Parameters  for disposal site  selection include:  avoidance of
 water  pollution  problems, avoidance  of air pollution problems, feasibility
 of construction  and  maintenance of access  road, site topography and size,
 availability of  cover  material, and  wind exposure.  The most important
 site  selection criterion is that it  should be located outside the water-
 shed  of the water supply source to eliminate any possible pollution
 effects.   The  site  should be on high,  dry  ground to avoid drainage and
 groundwater problems [27].  If there is a  prevalent wind direction, the
 site  should be located  down-wind from  the  community, so that unpleasant
 odours or  smoke  from burning at the  dump are directed away from the
 settlement.  The ground between the  disposal site  and the community must
 allow  for  the  construction and maintenance of a year-round access road.
 The distance from the  site  to  the  nearest  homes should be at least 1 km
 where  possible.  When  there is a choice between alternative sites, the
 construction and maintenance costs for a multiple-use access road should
 be considered  against  those for a  single-purpose waste disposal site
 access road.
         A sloping  site is  preferable  since it  facilitates dumping and
 spreading operations.   On flat land  a  slope can be created through
 deposition of  waste  and cover  material, where available.  The area for
 the dump/landfill operation should be  large enough to allow for 5-10
 years or longer operation,  particularly when the cost of the access road
 is high.  Usually land  area is not a problem.   A smaller area may be
 prepared and fenced  for current usage,  with adjacent room for expansion
 available.  The fenced  site should be  large enough to allow for deposition
of garbage and refuse and  a close-by storage  of cover material.  The cold
northern climate makes  biological  degradation of putrescible matter so

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                                 13-10
slow that the value of occasionally covering  the  waste  is  really only in
preventing garbage and paper from being blown  around  the site,  and in
reducing the danger of disease  transmission through insects,  birds and
animals.  Periodic compacting and covering of  the waste  is,  therefore,
recommended where at all economically  possible.   Availability of nearby
cover material is, therefore, important.  In  some cases, snow has been
used as a cover material.  The  requirement for fencing  is  based on
similar reasoning.  It will confine the blowing of waste to  the site and
may keep out larger land animals.  It  has also the psychological advantage
of creating the impression of an "engineered"  operation.   Where there is
a choice, a protected, less windy site will be preferable.   The controlled
burning of combustible material at the disposal site  serves  the useful
purpose of volume reduction and odour  control,  but may  create air pollu-
tion and smoke problems.  In some areas it may also not  be permitted.
         The provision of space for dumping of large, discarded items
such as automobiles, machinery, demolition material,  etc. must  also be
considered.  Where space allows, it is preferable to  locate  such an area
near the garbage dump.  This eliminates the need  for  a  separate road and
allows the periodic bulldozing  and "compacting" of that  area.  Not
providing such a facility will  encourage indiscriminate  dumping.  It is
also necessary to have available a tow truck  or other vehicle capable of
loading, hauling and unloading  inoperable vehicles and  machinery.
         If these simple guidelines of site selection and  operation are
adhered to, the environmental effects  of the  open dump/landfill are
minimized.  Under these circumstances, the advantages of cost and ease of
operation make it the most sensible method of  waste disposal  at the
present time.  The site should  be selected by  experienced  people with the
help of aerial photographs and  inspection of  alternative sites.  It
should not be left up to the garbage crew to  choose the  site(s).
Reclamation of land from the ocean by  the building of a berm off shore
and the filling in with solid waste, earth and rock are  carried out in
Godthab, Greenland, and Pangnirtung, N.W.T.   This may have application in
other areas where land is scarce.
         Because of the different nature of the waste,  bagged human
wastes should be disposed of separately from  solid waste,  as  discussed
later (see Section 13.4.3).

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                                  13-11
          Figures  13-5 to 13-11 show some of the situations experienced at
existing  disposal sites.
13.2.3.2  Modified landfill.   The proper application of sanitary
landfill  procedures  is usually impossible in permafrost areas.  The low
temperature  does  not permit  the degradation of putrescible matter to
occur, but merely places the waste in cold storage.  Excavation is
extremely difficult  and may  create difficulties through destruction of
the  insulating  layer.  Earth cover material must often be transported
considerable  distances to the disposal site and is therefore expensive.
Daily or  even weekly covering becomes economically impossible.  The small
size of most  communities makes it  seldom practical to keep a bulldozer on
the  site  continuously, as it is needed for other tasks in the community.
For  these reasons sanitary landfill is generally not a practical method
of disposal  in  permafrost areas.   In discontinuous permafrost areas, and
where cover material is available  at reasonable cost and the size of the
operation allows  the continuous presence of equipment, a form of land-
fill approaching  the practices of  sanitary landfill in southern areas is
a practical alternative.   The comments on site selection and preparation
given earlier in  the discussion of the open dump should be adhered to.
Articles  by Straughn [13]  and Cohen [14]  provide further information.
          Another  form of  the modified landfill is  a trench method.  In
communities which have piped service systems,  tractor-mounted back-hoes
are normally  available for systems maintenance.   These can be used to dig
trenches  at the solid waste  disposal site,  up  to about 3 m deep.  The
refuse is dumped  into these  trenches and,  when nearly full,  they are
covered with  excavated material  (about 1 m).   New trenches ,are then dug.
This method can be used in permafrost  areas, provided the machinery is
able to dig such  trenches.
         Another  possible  variation,  not  yet tried on a community scale
in northern regions,  is composting [31]  of  garbage,  kitchen  wastes and
human waste either on  an  individual  household  basis  or on a  community
basis.  Experience with municipal  composting operations  in Europe would
indicate  that it  is  not  likely  to  be  economically  feasible in most of the

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                  13-13
FIGURE 13-7.
ATTEMPT TO CREATE A DUMPING
SLOPE ON FLAT TERRAIN  (a)
FIGURE 13-8.
ATTEMPT TO CREATE A DUMPING
SLOPE ON FLAT TERRAIN (b)

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                   13-14
 FIGURE 13-9.  HOW WOULD YOU LIKE THIS JOB?
FIGURE 13-10.
DISPOSAL OF GARBAGE AND HONEY
BAGS AT THE SAME SITE.  THIS
SHOULD NOT BE DONE.

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                                  13-15
                 FIGURE 13-11.   STORAGE  TANK DISPOSAL
                                 ONTO GARBAGE DUMP
northern communities  because  of  their  small size and  because of the
climate.
13.2.3.3 Ocean disposal.  Many of  the  smaller  communities  on the ocean
dispose of their garbage  and  "honey bag" wastes by placing them on the
ice in the winter, relying  on spring breakup to wash  away  the material
[5],  The remoteness  of the communities, the relatively small quantities
of waste involved and  the vastness of  the  ocean make  this  practice
tolerable for small communities.  Future legislation  may prohibit this
practice.
13.2.3.4 Incineration.  Incineration is  a  controlled  process for
oxidizing combustible  waste to carbon  dioxide, water  and ash.   Normal
domestic garbage and  refuse has  an average heating value of  about 11.6
megajoules/kg and thus can be considered a valuable fuel resource,
particularly in northern areas where fuel must be  brought  in at great
expense.  Some years ago it was  thought  that incineration  had  great
potential for Alaskan  communities and  might replace the  practice of open
dumps [5],  However, the experience of the few installations that have
been built at federal  facilities [5,10] and in parts of  the  Alaska

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                                 13-16
Village Demonstration Project (AVDP) has been that incineration of  solid
wastes is not economically feasible for communities because of high
operative and maintenance costs.  As a result, many installations are  in
fact not being operated now.
         Zaidi and Curran [38] recently carried out three  test runs on a
new type of forced-air open  pit incinerator constructed at the Gordon
Indian Reserve in northern Saskatchewan.  The rate of generation of
domestic solid waste at Gordon, excluding the waste generated at the
residential school, was in the range of 907-1360 kg/week,  or 4.2-7  m
week.  The average composition (weight %) of the waste  samples burned  was
46% paper, 37% food, 3% plastic, 8% metal and 6% glass.   It should  be
noted that approximately 50% of the paper waste was disposable diapers.
         The incinerator is  a skid mounted, single chamber open pit type
incinerator capable of burning approximately 227 kg/h of  municipal
type solid wastes.  The combustion chamber is a refractory-lined metal
box with an inside volume of 2.7 m .  It is designed to achieve a
temperature of 871C by supplying up to 840 m /h of underfired
and overfired air through manifolds and nozzles mounted on both sides  of
the combustion chamber.
         From these three test runs it was found that the  uncombustible
residue obtained from the incinerator indicated a  fairly  complete
combustion.  The residue volume was approximately  15% of  the refuse.
Also, to get a good fire burning in the incinerator, the  volume of  the
refuse at the beginning should be kept to a minimum.  Therefore, it was
recommended that the collection of refuse be done  in three batches  with
the first one being the smallest [38].  Further testing of this facility
is planned.
         Incineration is one of the most common methods of disposing of
solid wastes from industrial and military camps [36].   It  is most
effective in reducing animal  scavenging of the camp site  and  the
environmental effects of incineration are low.  For very  small, short
duration camps for exploratory purposes backhaul or open  burning  is
practised.  For larger  temporary and all permanent or  semi-permanent
camps incinerators of various designs are used; they are  normally  oil
fired.  Because of much better qualified operators than in communities,

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                                  13-17
maintenance problems and  costs are  substantially  reduced.   Operating
costs are generally not available.   They are  probably high  when
considered within an economic framework of a  community,  but  are  not
significant when considered against  the overall cost of  industrial or
military camp operations.
13.2.3.5 Milling and compaction.  The purpose of  milling and compaction
is to reduce volume, and  thereby make handling and disposal  of the wastes
cheaper and more manageable.  Included here are methods  to  shred, mill or
grind wastes, and to compact or bale wastes.  They may be used ahead of
landfilling, incineration or in conjunction with  materials  recovery.  To
date the record of a number of pilot or full-scale projects  appears to
increase overall disposal costs, rather than  decrease them.
         Refuse milling (or shredding, or grinding) is a process by which
refuse is passed through  a mechanical device, such as a  hammer mill,
which grinds it to a homogeneous mixture of a specified  maximum  size.  This
mixture is inoffensive, light, highly compactable, and easily handled.
Paper plastic, wood, and  cardboard  are generally  broken  into three to four
inch pieces.  Glass is shattered so  thoroughly into sandlike particles that
it is impossible for the  casual observer to detect it.   The  raw  garbage is
generally absorbed and is so finely mixed with paper and other materials
that there is very little odour.  The biggest problem is with soft plastic
bags, which tend to stretch rather  than tear  apart [5].
         Milling ahead of landfilling reduces the need for  daily cover
and the "nuisance aspects" of open  dumps (odour,  flies,  rats, windblown
material).  It also reduces the volume to be  transported and disposed of.
Difficulties in northern  operation  of a hammermill, or other type of
mechanical equipment, are with the  input of frozen wastes and increased
frequency of mechanical breakdown and difficulty  of repair.   Many
communities are too small to justify the high capital cost  and operating
costs.  Forgie [16] reported on a Canadian pilot  project on  shredding of
solid waste. It showed that shredding by a hammermill may be technically
feasible but failed to provide information on the economic  feasibility
for northern applications.

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                                 13-18
         Compacting or baling is a process whereby waste, raw or milled,
is compressed into bales, with a significant increase in density (up to .
kg/L, which is about the density of water).  After being banded, these
bales are hauled to a landfill site, where they can be stacked  in place.
In this manner, greater landfill density can be achieved, and
transportation costs are reduced, since greater payloads can be hauled.
High pressure baling, which does not require banding, is planned for
Fairbanks, Alaska.
         There is a lack of published economic analyses of these methods
which prevents a firm conclusion about their possible application in
northern areas.  At present it appears that their benefits can  be
achieved by simpler methods and managements as discussed previously
[24].
13.2.3.6 Recycling and reuse (haulback).  Recycling of waste into
regenerated products is now popular.  There are difficulties achieving
this objective in the economic framework of southern communities, and in
remote northern communities the picture is even less attractive.
Recycling and reuse requires, in many cases, sorting and separation of
wastes, as for instance in the recovery of metal cans, glass products,
etc.  The size of the operation and the availability of markets for the
'usable' waste products are important economic considerations.  A
northern location compounds the difficulties experienced in  the southern
communities.  Populations are generally small; therefore, volumes of
recovered materials are small.  There are usually no local markets and,
therefore, material must be shipped south over long distances and at high
costs.
         Some apparently successful projects of recycling scrap metal
have been reported by Kelton [5],  In one project, approximately 40 000
tons of heavy metal scrap was removed from a Fairbanks junkyard and
transported by the Alaska Railroad to Seward, where it was shipped  to
Taiwan for recycling, all without a government subsidy.  Another example
is in Anchorage, where a private wrecking firm collects, crushes and
transports junked automobiles to Seattle, at a government subsidy of $22
per vehicle (1975).  The problem of junked automobiles is discussed
further in Section 13.3.

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                                 13-19
13.2.3.7 Costs and charges.  Actual charges to the homeowner  are not well
documented.  However, information is available on the actual  cost  for
garbage collection and disposal in some northern communities.   It  is
important to differentiate between actual costs and charges.   The  latter
are mostly subsidized, and set without knowing real costs.
         Gamble and Janssen [28, 32] describe a method  to estimate  the cost
of garbage collection in small communities.  For the example  illustrated,
Tuktoyaktuk, N.W.T., the cost per bag ranged between $1.49 and  $2.89.
There is a need to document costs of collection and disposal  in a number
of typical communities.
         In Alaska, the average charge to the homeowner  for collection of
garbage (one drum per week) in incorporated municipalities of  over  500
population was $4.80 (2.50 to $15.00) per month per household  in 1974  [5],
or about $1.20 per drum.  In communities of the N.W.T.,  charges varied
between 40fc and $1.00 per drum in 1972 [20].
         In Table 13-5, some typical values are given for the  actual
costs (labour, vehicle O&M, overhead, etc.) to maintain  garbage collec-
tion and disposal in some representative northern communities  [39].  The
costs are given as either a flat rate charged per pick-up and/or as the
cost per person per year to maintain such a system.
                  TABLE 13-5.  GARBAGE COLLECTION COSTS
Community
Coppermine
Fort Liard
Fort Resolution
Gjoa Haven
Fort Good Hope
Fort McPherson
Fort Norman
Paulatuk*
Aklavik
Chesterfield
Inlet*
Year of
Survey
1976
1977
1976
1976
1976
1976
1976
1977
1976
1976
Population
Serviced
758
225
600
420
443
710
232
147
781
243
Cost
$1.30/pick-up
$1.25/pick-up
$1.10/pick-up
$1.86/barrel
$1.28/pick-up


$1.15/pick-up



$15/person/yr



$16 . 25/person/yr
$14 . 25/person/yr
$38. 47/person/yr

$12. 17 /per son/ yr
$44 . 90/per son/yr
* Labour contract only.

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                                 13-20
         From Table 13-5 it can be seen that the  smaller  communities  have
the higher per capita cost.  This is reasonable because each  community
will require similar infrastructures to allow for  the  garbage  collection
system.
13.3     Industrial and Special Solid Wastes
         Included under this heading are solid wastes  generated  from
industrial activities, special wastes such as discarded automobiles,
mobile houses, ski-doos, vessels, oil barrels, machinery  and  other bulky
waste, as well as special wastes associated with  temporary  or  permanent
camps.
         It is believed that no comprehensive survey has  been  done of the
solid waste problems of industry in Alaska and the Canadian northern
territories and provinces.  Kelton [5] has provided some  information  on
the special problem of seafood processing wastes  in Alaska, which are
disposed of in the ocean or in a landfill.  A great part  of industrial
activity in the North is connected with the extraction of raw materials
(oil, gas, various minerals, etc.).  It is beyond the  scope of this
manual to discuss the special solid waste management problems  of these
industries in detail.  Reference should be made to the relevant
information on such industrial wastes in other areas.
         Special wastes, other than garbage and refuse,  from  communities
and camps include discarded automobiles, mobile homes, construction
equipment and materials, ski-doos, bulky containers and  shipping
material, and others.  These wastes do not accumulate  on  a  frequent basis
and are normally not collected and disposed of routinely.  However,
provisions must be made to provide an incentive for reuse,  where this is
feasible, and more importantly, for a dumping area, which is  controlled
and operated by the municipality.  In the absence of this,  discarded
material seems to be left almost everywhere.  This contributes greatly to
the too often justified impression of unorganized and  poorly  managed
communities.
         Some quantity information is available.   Alter  [6] stated:  In
cold regions it may be assumed that the following percent of  the total
weight or volume of each item becomes solid waste annually:

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                                  13-21
         - Lumber,  steel  and  other  building  material  used
           in  construction  of fixed facilities  such as
           buildings                                                   3%
         - Heavy  equipment, tractors, machinery and vehicles         10%
         - Miscellaneous  freight  such as  canned goods,
           furniture,  appliances, etc.                              2-10%
         - Magazines,  books,  newspapers,  etc.                         90%
         - Office and  household furnishings                         5-10%
         - Clothing                                                   30%
These estimates may, in fact,  be  on the low  side.   For  example,
machinery and  cars  accumulate more  likely at a  higher rate.   Kelton [5]
estimated that of the  170 000 vehicles registered  in  Alaska  in 1973 about
20 000 are junked each year.   At  an average  weight  of 1.5 tons per
vehicle this amounts to 30  000 tons of scrap per year.   Recycling in the
larger and less remote communities  may be economically  feasible,  but not
likely to be the  case  in  the  more remote  communities  because of  high
freight rates.  There  is  a  choice to be made either between  subsidizing
backhaul or providing  local junk  yards.   Forgetting about the problem is
not acceptable.   In the absence of  state-or  territory-wide policies, the
minimum that a local community must do is to establish  'controlled'  junk
yards, prohibit the indiscriminate  abandoning of discarded material on
public and private  property,  and  establish a collection  method at a fee
and on demand.
         The special problems  of  solid waste management  for  temporary and
semi-permanent camps (together with their water supply  and wastewater
disposal problems) have been  discussed thoroughly  by  Grainge et  al [18],
13.4     Human Wastes  from Households and Establishments
         The replacement  of the "honeybag/honeybucket"  system for human
waste disposal with other methods would be the  greatest  single
improvement in the  living conditions of northern communities and  would
contribute to a reduction in  waste-borne  diseases  [2],
         Hanks [21] has conducted an exhaustive literature study  on the
relationship of solid  wastes  and disease.  While the  literature  failed to

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                                 13-22
permit a quantitative estimate of any solid waste/disease relationship,
this was said in summary:
         "The communicable diseases most incriminated are those whose
         agents are found in fecal wastes - particularly human fecal
         wastes.  Where these wastes are not disposed of in a sanitary
         manner, the morbidity and mortality rates from fecal-borne
         diseases in the population are high.  Despite the fact that
         other factors are known to contribute to some reduction  of these
         rates, the inescapable conclusion is that the continued  presence
         in the environment of the wastes themselves is the basic
         causative factor.  Therefore transmission - whether by direct
         contact vector transfer, or indirect contact - is due to
         environmental contamination of these wastes."
       No other place in North America exists where this statement
applies more than in northern communities.  There is a lack of conclusive
data for solid waste/disease relationships in northern communities, but
the problem is there.
         The bucket toilet system, better known as the 'honeybag1 or
1honeybueket' system, exists because of the high cost of conventional
piped sewer systems, and the unsuitability of the septic tank-tile bed
system in most northern areas.  Piped water and sewer systems, above or
below ground, suitably modified to northern conditions, have been
installed in many of the larger communities.  The essential goal  appears
to be the replacement of the honeybag system by a piped system, by a
holding tank/truck system, or by new methods such as internal recycle
systems.  However, because of the many priorities for funds, it is
reasonable to expect that the honeybag system will continue to be widely
used for a considerable number of years.  Improvements in current
praotioes are possible and discussed here.  Surveys of communities'
municipal servicing standards, including human waste, were made  for  the
N.W.T.  [19], the Yukon Territory [30] and Alaska [34].
13.4.1   Storage at the house and collection
         Figure 13-12 shows a typical bucket toilet.  Health officials
recommend that honeybags be collected from all households daily.  This
also assists the collection procedure since a half-full bag  is less
likely to break.  Daily collection, however, is the exception rather  than
the rule.

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                                  13-23
                   FIGURE  13-12.   TYPICAL BUCKET TOILET
         There are  three  methods  of  honeybag  storage and collection [20]:
         a)  collection from  oil  drums  in  front of  each household,
         b)  collection from  the  bathroom  of  each household,
         c)  collection from  the  service porch  of each household.
a)       The householder  is supposed  to  remove  the  honeybag from the
bucket toilet and  place the sealed bag  in  a drum, reserved for this
purpose, in front  of his  house.   Often,  the bag is  left on the ground,
where it is broken  by birds,  dogs or  children,  or where it can freeze to
the ground in winter.  The presence  of honeybags  lying around the
settlement is aesthetically unpleasant.  If broken,  they constitute a
danger to health.   Removal of honeybag debris is  unpleasant,  inconvenient,
and difficult.  Handling, first by the householder  and then again  by the
collector, increases the  possibility  of  breakage.   This method is  not
recommended (Figure 13-13).
b)       A system of in-house collection of honeybags  from the bathroom
has been implemented in some  communities.  The  honeybag collector  enters
the house and removes the honeybag and pail to  the  truck.   After dumping,

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                                 13-24
               FIGURE 13-13.  MANUAL HANDLING  OF HONEYBAGS
                              STORED IN DRUMS  IN FRONT  OF THE
                              HOUSE UNTIL COLLECTION
a new bag is placed in the pail and the pail is returned to  the  bathroom.
The system is advantageous in that handling of the honeybag  only once by
the collector minimizes the chance of breakage.  It is  convenient to  the
householder, requiring no conscious actions on his part.  Honeybags are
not left around the roads of the settlement where they  may be  broken.
Residents in at least one community have objected strongly to  collection
from the bathroom as a serious inconvenience,  which dirties  up the house
and invades their privacy, and about which they were  not consulted before
the system was placed in operation.
c)       A variant of b) is the service porch  or "two-bucket"  system.
Each household has two plastic or metal pails  for its toilet (Figure
13-14).  Each morning the householder ties the top of the bag  and places
the plastic pail and full bag in the service porch for  collection. The
second pail, with an empty unused plastic bag  inside, is placed  in the
toilet for use.  The collector removes the used bag from the pail and
replaces it with a fresh bag.  The pail is left on the  service porch  for

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                                  13-25
                  FIGURE 13-14.  METAL BUCKETS  USED FOR
                                 COLLECTION OF  HUMAN WASTE
use the next day, and  the  "full" honey bag  Is  taken to the collection
vehicle for disposal.  The  two-bucket  system is advantageous in that it
minimizes handling  of  the  bag,  is  clean,  and does  not leave honeybags
lying around the  settlement.   The  major objection  to the in-house system
- the invasion of privacy  - is  not present.   The two-bucket system requires
that all homes have an accessible  service porch and two toilet pails.
         Trucks, on which  tanks or drums  are mounted for storage, are
used to haul the wastes to  the  disposal site.   The most practical tank is
a half-round shape  with a  large manhole having  a hinged lid on the back
in the flat cover.  The flat  top allows for a  lower emptying point.
Steps are provided  on  the  side  so  that honey buckets can be carried up
and emptied into the tank.   The tanks  usually have a capacity of 2000 to
3000 litres.  The truck should  be  kept as small and manoeuvrable as
possible to get close  to the  houses.   The tank  should be capable of being
dumped at the disposal site.  At the rear a large  valved outlet pipe (at
least 20 cm in diameter) is  provided which  can  be  opened to empty the
tank.  A small heater  is needed to keep the  short  pipe and valve

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                                 13-26
from freezing.  The truck exhaust  can also  be  routed  to  keep this valve
warm and eliminate the need  for a  heater.   A full  opening,  non-rising
stem gate valve has proven best for  this application  as  it  must be
capable of passing solids such as  plastic bags.  A steam cleaner should
be mounted on the side of the tank so the honeybuckets can  be cleaned
before replacement in the house.   Typical costs  for the  truck,  tank and
cleaning unit would be about $40 000 (1977).
         Another type of truck has a large  holding tank  which is equipped
with a dumping drum with spikes on the  interior  of the drum.  The full
honeybag is placed in the drum by  the driver and broken  on  the  spikes by
an upward hand motion.  The  contents flow or are sucked  into the holding
tank, and the ripped bag is  placed in an oil drum  for the purpose of
storage before disposal (Figure 13-15).  In a  simpler case,  honeybags are
placed in oil drums on the back of a tractor-driven cart or  pick-up
truck.  The drums with their contents are dumped at the  disposal area and
the drums reused.
                                                         J
                  FIGURE 13-15.  REAR VIEW OF HONEYBAG
                                 SUCTION VEHICLE

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                                  13-27
         In some communities, homeowners must  carry the  bagged wastes to
a disposal point.  Normally, several  disposal  points are located in the
village, and wastes are  hauled  from  there  by  truck to the disposal site.
Disposal points must be  centrally  located  to  all  dwellings;  otherwise
their chances of being used  regularly are  small.   The distance that
individuals will haul wastes varies  with many  factors.  Two  of the more
important considerations are training and  education of the users and the
ground conditions over which the wastes must be hauled.   Experience
indicates that the number of individuals who  utilize a disposal point
starts dropping off considerably after the  distance exceeds  200 metres.
Also, the people tend to haul longer  distances in the winter because in
most communities it is easier to get  around and snowmobiles  can be used.
An extensive education program  is  invaluable  in promoting the use of a
disposal point when individuals are  hauling their own waste.
13.4.2   Quantity and composition  of  human wastes
         Heinke and Prasad  [22,23] have provided  data for honeybag wastes
(Table 13-6).
         Data from a Canadian community [9] substantiate the estimated
volume of about 1.3 L/person/day.
13.4.3   Disposal
         Disposal of the contents  of  honeybags can be accomplished in
several ways.  They are:  at a  treatment plant or a lagoon treating
sewage from a piped system; at a sludge pit-lagoon;  at a disposal site
next to the garbage dump; on the ice;  and  in  the  ocean.
         The most satisfactory disposal method for honeybucket wastes
would be at a central facility, such  as a  treatment plant where the
wastes are a small part  of  the  total  waste load to the facility.  The
treatment would be accomplished by one of  the methods discussed in
Section 9.   A fly-tight closable  box should be provided on  the outside
of the building which is convenient  to use.  It must be  capable of being
thoroughly washed down and  cleaned daily.  Above  all,  it must be
aesthetically pleasing and  easy to use; otherwise it will not be used.
It must also be vandal-proof.  This  disposal method depends, of course,
on the existence of a partial sewer  system and treatment facility, where

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                                 13-28
         TABLE 13-6.  CHARACTERISTICS OF HUMAN WASTE (Honeybags)
Parameter
Volume, litres per person per day
PH
Alkalinity, mg/L
Total solids, mg/L
Volatile solids, percent of total solids
Dissolved solids, mg/L
COD, mg/L
Supernatant COD, mg/L
TKN, mg/L
NH3-N, mg/L
Org. N, mg/L
Phosphorus (PO^, mg/L
Volatile acids, mg/L
Total Coliform Count, no. per 100 ml
Average
1.3
8.78
14 990
78 140
77.53
39 290
110 360
48 510
8070
3920
4150
3730
2490
5.4xl08
Range
-
8.6 - 8.9
11 900 - 17 000
65 990 - 85 030
71.53 - 80.18
32 500 - 53 620
80 750 - 134 820
39 990 - 61 280
7280 - 9520
3470 - 4060
3696 - 5520
3400 - 4250
2300 - 2670
1.5xl08-2.3xl09
honeybags are used only in a portion of the community.   If  the  wastes  are
deposited in a lagoon a dumping point should be designed  to  prevent
erosion of the lagoon dykes yet allow for easy access  so  the  waste
doesn't end up all over the dykes instead of in the  lagoon.   A  platform
with a hole cut out over the water seems to be satisfactory.  Another
problem with lagoon disposal is the plastic bags  which are  often  used  as
liners in honeybuckets.  They are not biodegradable  and should  not  be
deposited in the lagoon.   It will be necessary to  empty their contents
into the lagoon and then deposit the bags at a landfill or  burn them.   If
honeybag wastes are dumped at a treatment facility this must  be taken
into account in their design.  Although the hydraulic  load  is small the
organic and solids loading is quite considerable  (see  Table 13-6).   The
waste may also contain a high concentration of deodorizers  such as
formaldehyde and pinesol,  which could affect biological treatment
processes.

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                                  13-29
          If  a  sewage  treatment  plant  or  lagoon does not exist, the most
satisfactory method  is  to  build a sludge pit,  lagoon or trench.  It must
be accessible  for  easy  dumping  of the contents of haulage tanks.  One way
would  be  to  cover  it  with  a  platform  which contains a disposal hole, and
covered with a fly-tight,  hinged lid. The waste pit should be located on
a site which will  never be needed for other purposes, and as far away as
practical  from the community and water supply  source.  It should be sized
                 o
for about  0.55 m  per person per year, and covered after one year's
operation  and  a new pit dug. If the  community has a partial sewer system
and a  lagoon is used  as the  treatment method,  the sludge pit should be
constructed  adjacent  to the  lagoon and liquid  overflow directed to the
lagoon.   Some  of the  liquid  portion of the honeybucket wastes will seep
out when  the surrounding ground is thawed.  As with privies, sludge pits
are not a  desirable form of  waste disposal if  the soil is frozen
fine-grained silts or where  there is  a high groundwater table.  If no
other  site is  available, lining of the pit to  prevent contamination of
the groundwater may be  required.
         A laboratory study  carried out  at the University of Toronto
[22,23] on a simulated  waste pit  showed  that it is possible to treat
honeybag waste  by  anaerobic  digestion at  20C  and that the process
may be applicable  at  lower temperatures,  but at the expense of very long
detention times.
         However,  it  does  not appear  economically reasonable to build an
anaerobic digester, with its requirement  for heating,  mixing and further
treatment of supernatant effluent,  for the overall primitive honeybag
system.  Disposal  in  a  properly located,  designed and  operated waste pit
or trench is preferable to disposal in a  garbage  dump  or in the ocean.
The two-year laboratory study,  simulating  a waste pit  in permafrost,
showed that  it  acts as  a holding  tank only.  No waste  treatment occurs.
Pathogens are  likely  to remain  viable in  the pit  for  many years.
         An improved  method  of  handling and disposal  of  honeybags  is
practised in Greenland  [8].  Two  communities (Holsteinsborg and
Egedesminde) have  changed  from  the  'bucket-toilet1  system to a 'bag'
system.  Homeowners are provided with strong paper  bags  lined with
plastic,  and closing  clips,  which  are  placed inside  the  bucket.  The bags

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                                 13-30
are picked up and transported by a flat truck to a disposal station  (see
Figure 13-16).  One man at the disposal station empties the bags  into a
discharge pipe (see Figure 13-17) leading to the ocean, below  low water
level.  The paper bags are burned.  This system is considered  a big
improvement in Egedesminde.  In Holsteinsborg plastic bags are used,
rather than paper bags with plastic liners, and problems are experienced
in burning the plastic bags.  The cost of the disposal station could not
be established but may be considerable, perhaps $150 000 (1973).  It
makes the solids handling much more acceptable to the operators.  The
expense of such a disposal station is justified only where the honeybag
system will continue to be used for many years.
         The dumping of honey bags at a landfill site, on the  ice or in
the ocean should not be encouraged, although there may be circumstances
which make this practice tolerable.  If honeybags are deposited at a
landfill site, this should be separate from the garbage.  Daily covering
with at least minimal material will prevent animals and birds  from
getting into it.  This is important to prevent disease transmission.
13.4.4   Costs and Charges
         Presented in Table 13-7 are the actual costs involved for a
honeybag collection system in some northern communities [39].  These
costs are either given as a set charge per pick-up and/or as the  actual
annual cost per person.  This includes labour, material, vehicle  O&M, and
overhead and profit costs for service provided by a contractor.
                 TABLE 13-7.  HONEYBAG COLLECTION COSTS
Community
Coppermine
Gjoa Haven
Fort Good Hope
Fort McPherson
Paulatuk*
Chesterfield
Inlet*
Year of
Survey
1976
1976
1977
1976
1977
1976
Population
Serviced
758
420
443
710
145
243
Costs
$1.20/pick-up
$2.l5/pick-up
$1.85/pick-up
$1.50/pick-up
$l.!5/pick-up


$32/person/yr
$50/person/yr

$32.10/person/yr

$56.80/person/yr
* Labour and materials  only.

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                      13-31
  FIGURE 13-16.  DISPOSAL STATION FOR HUMAN WASTE
                 AT EGEDESMINDE, GREENLAND
FIGURE 13-17.  VIEW OF INSIDE OF DISPOSAL STATION,
               EGEDESMINDE, GREENLAND

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                                 13-32
         Since all population sizes require similar infrastructures for

the honeybag system, it can be seen that the smaller population sizes

will have a higher per person cost.  This, in fact, is supported by the
above data.

13.5     References

1.   Associated Engineering Services Ltd. "Solid Waste Management in the
        Canadian North", Environment Canada, Ottawa, March 1973.

2.   Heinke, G.W., "Solid Waste Management in the Canadian North",
        Environment Canada, Ottawa, March 1973.

3.   D.R. Stanley Associates Ltd. "Solid Waste Management in the Canadian
        North", Environment Canada, Ottawa, March 1973.

4.  Underwood and MoLellan, "Solid Waste Management in the Canadian
        North", Environment Canada, Ottawa, March 1973.

5.   Kelton, K., "Comprehensive Plan for Solid Waste Management", Alaska
        Department of Environmental Conservation, Juneau, Alaska,
        January 1975.

6.   Alter, A.J., "Solid Waste Management in Cold Regions", Scientific
        Research Data and Reports, Vol. 2, No. 2, Dept. of Health and
        Welfare, State of Alaska, College, Alaska, August 1969.

7.   Grainge, J.W., "Study of Environmental Engineering in Greenland and
        Iceland", Manuscript Report No. NR-69-5, Div. of Public Health
        Eng., Canada Dept. of Nat. Health and Welfare, Ottawa,  1969.

8.   Heinke, G.W., "Report on Environmental Engineering in Greenland and
        Northern Scandinavia", Publ. Dept. of Civil Eng. 73-05, Univ. of
        Toronto, October 1973.

9.   Associated Engineering Services Ltd, "Report on Tuktoyaktuk Water
        Supply and Waste Disposal" to Govt.  of N.W.T., Yellowknife, July
        1974.

10.  Smith, D.W. and Straughn, R.O. , "Refuse Incineration at Murphy Dome
        Air Force Station", Arctic Health Research Centre, Fairbanks,
        Alaska, 1971.

11.  Grundtwaldt, J.J., Tilsworth, T. and Clark,  S.E., "Solid Waste
        Disposal in Alaska".  In  :  Smith, D.W. and Tilsworth,  T.,
        Environmental Standards for Northern Regions,  A Symposium,
        Institute of Water Resources, U. of Alaska, Fairbanks,  1975.

12.  Can-Brit. Engineering Consultants Ltd., "Study of Solid Waste
        Management at Indian  Settlements in Northern Ontario",  for
        Environment Canada, Ottawa, March 1975.

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                                 13-33
13.  Straughn, R.O., "The Sanitary Landfill in the Subarctic", J. Arctic
        Inst., Vol. 25, No. 1, March 1972.

14.  Cohen, J.B., "Solid Waste Disposal in Permafrost Areas", Proc.
        Second Int. Conf. on Permafrost, Yakutsk, pp. 590-598, Nat. Acad.
        Sci., Washington, D.C., July 1973.

15.  U.S. Army Corps of Engineers, "Technical Evaluation Study,  Solid
        Waste Disposal, Fort Greely, Alaska, Office of the District
        Engineer, U.S. Army Corps of Engineers, Anchorage, Alaska, July
        1972.

16.  Forgie, D.J.L., "Shredded Solid Waste Disposal", IN Some Problems of
        Solid and Liquid Waste Disposal in the Northern Environment,
        Environment Canada Report EPS-4-NW-76-2, pp. 43-85, Edmonton,
        November 1976.

17.  Black, R.J., Munich, A.J., Klee, A.J., Hickman, L.H. and Vaughn,
        R.D., "The National Solid Wastes Survey - An Interim Report",
        U.S. Dept. of Health, Ed. and Welfare, October 1968.

18.  Grainge, J.W., Edwards, R. , Heuchert, K.R. and Shaw, J.W.,
        "Management of Waste from Arctic and Subarctic Work Camps",
        Environmental-Social Committee, Northern Pipelines, Task Force on
        Northern Oil Development, Government of Canada, Ottawa,  1973.

19.  Heinke, G.W., "Report on Municipal Services in Communities of the
        Northwest Territories", Information Canada, Ottawa, Cat. No.
        R72-12674, INA Publ. No. QS-1323-000-EE-A1, 1974.

20.  Cadario, P.M. and Heinke, G.W., "Manual for Trucking Operations for
        Municipal Services in Communities of the Northwest Territories",
        University of Toronto, Publication of Department of Civil
        Engineering, October 1972,

21.  Hanks, T.G., "Solid Waste/Disease Relationships, A Literature
        Survey", Publ. of Public Health Service, U.S. Dept. of Health,
        Education and Welfare, Report SW-K, Washington, D.C., 1967.

22.  Heinke, G.W., "Preliminary Report on Disposal of Concentrated Wastes
        in Northern Areas", in Report 74-10, Environmental-Social
        Committee, Pipelines, Task Force on Northern Oil Develop., Inf.
        Canada, Cat. No. R72-13474, QS-1577-000-EE-A1, Ottawa, 1974.

23.  Heinke, G.W. and Prasad, D., "Disposal of Concentrated Wastes in
        Northern Areas", IN Some Problems of Solid and Liquid Waste
        Disposal in the Northern Environment, Environment Canada Report
        EPS-4-NW-76-2, pp. 87-140, November 1976.  Also in Proc. 3rd Can.
        Hydrotech. Conf., Can. Soc. Civ. Eng., Laval University, Quebec,
        pp. 578-593, 1977.

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                                 13-34
23.  Stanley Associates Eng. Ltd., "Baling for Solid Waste Management at
        Baker Lake, N.W.T.", prepared for Northwest Region, Environmental
        Protection Service, Environment Canada, Edmonton, 50 pp., 1974.

24.  Underwood McLellan and Assoc. Ltd., "Report on Study of Pollution
        Control Systems, Resolute, N.W.T.", Report to:  Government of the
        Northwest Territories and Environment Canada, Environmental
        Protection Service, Edmonton, 1974.

26.  Watmore, T.G., "Problems of Waste Disposal in the Arctic
        Environment", Industrial Wastes, Zl(4), 24, 1975.

27.  Zenone, C., Donaldson, D.E., and Grunwaldt, J.J., "Groundwater
        Quality Beneath Solid Waste Disposal Sites at Anehorage, Alaska",
        Groundwater, 1.3_(2), 180-190, 1975.

28.  Gamble, D.J. and Janssen, D.T.L., "Estimating the Cost of Garbage
        Collection for Settlements in Northern Regions", The Northern
        Engineer, _6(4):32-36, 1974.

29.  Heuchert, K.R., "Refuse Sack Collection System Study", IN Arctic
        Waste Disposal - Social Program, Northern Pipelines, Task Force
        on Northern Oil Development, Report No. 74-10, pp. 1-22, 1974.

30.  Stanley Associates Eng. Ltd., "Final Report on Community Services
        Improvement Program, Yukon Territory", prepared for:  Dept. of
        Local Government, Government of the Yukon Territory, Whitehorse,
        292 pp., 1974.

31.  Lindstrom, C.R., "Clivus-Multrum System:  Composting of Toilet
        Waste, Food Waste and Sludge within the Household", IN:  Rural
        Environmental Engineering Conference on Water Pollution Control
        in Low Density Areas, September 26-28, 1973.  Warren, Vt.,
        Published by University Press of New England, Hanover, N.H., pp.
        429-444, 1975.

32.  Gamble, D.J.- and Janssen, C.T. , "Evaluating Alternative Levels of
        Water and Sanitation Services for Communities in the Northwest
        Territories", Can. J. of Civil Eng.. 1(1): 116-128, 1974.

33.  Ryan, W.L., "Village Sanitary Problems", In:  Environmental
        Standards for Northern Regions, June 13-14, 1974.  D.W. Smith and
        T. Tilsworth, eds., Inst. of Water Resources, Univ. of Alaska,
        pp. 315-320, 1975.

34.  Village Sanitation in Alaska - Inventory.  Office of Environmental
        Health, U.S. Public Health Service, Anchorage, Alaska.

35.  Alaska Department of Environmental Conservation, "Waste Oil/Water
        Quality Problem Description" (Draft Report), Juneau, Alaska,
        November 1977.

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                                 13-35
36.  Associated Engineering Services Ltd., "Waste Management for Northern
         Work Camps", Environment Canada, Northern Technology Centre,
         Edmonton, April 1978.

37.  W.O. Wardrop and Associates Ltd., "Burning Practices in the
         Northwest Territories", (Draft Report), Regina, March 1978.

38.  Zaidi, A. and Curran, B., "Open Pit Incinerator", Report of
        Saskatchewan District, Environmental Protection Service,
        Northwest Region, Environment Canada, Regina, April 1978.

39.  Doulton, B., "Water and Sanitation Operation and Maintenance Costs -
        A Consolidation of Historic Information", prepared for the
        Dept. of Looal Govt., Government of the Northwest Territories,
        Yellowknife, 1978.

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                                 SECTION 14
                              ENERGY MANAGEMENT
                                    Index

                                                                     Page
14       ENERGY MANAGEMENT                                           14-1
14.1     Basic Considerations                                        14-1
14.1.1   Energy requirements                                         14-1
14.1.2   Climate design information                                  14-3
14.1.3   System utilization and feasibility                          14-4
14.2     Energy Supply                                               14-5
14.2.1   Fuels and storage                                           14-6
14.2.2   Heat and power production                                   14-12
14.3     Energy Distribution                                         14-21
14.3.1   Electric power distribution                                 14-22
14.3.2   Heat distribution                                           14-29
14.3.3   Gas distribution                                            14-38
14.4     References                                                  14-43

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                              List of Figures
Figure                                                                Page
14-1     Kinematic Viscosity as a Function of Temperature  for
         Various Fluids                                               14-7
14-2     Output Characteristics of Various Common Electric
         Generating Systems                                           14-14
14-3     Determination of Optimum Energy Cost and Plant  Size
         for Base and Peak Load Generating Plants                     14-16
14-4     Winter Sea Temperatures off Alaska                           14-18
14-5     Hot Water Accumulator for Thermal Storage Showing
         Typical Interface Characteristics                            14-19
14-6     Overhead Aerial                                              14-25
14-7     Underground Cable Guidelines                                 14-25
14-8     Directly Buried Hot Water Distribution Piping                14-32
14-9     Installation of Heat Distribution Lines in Seasonal
         Frost Areas                                                  14-33
14-10    Diagram for Determining the Required Insulation for
         Frost Protection of Soils and Pipelines                      14-35
14-11    Installation of Heat Distribution lines in Permafrost
         Areas                                                        14-36
                             List of Tables
Table                                                                 Page
14-1     Residential Energy Requirements                              14-1
14-2     Commercial and Institutional Energy Requirements             14-2
14-3     Rubber and Plastic Compounds Comparison                      14-24

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                                   14-1
 14         ENERGY MANAGEMENT
 14.1       Basic Considerations
           A community requires energy for heating buildings, for lighting,
 for operating  appliances and for domestic hot water.  Transportation energy
 needs  are  not  supplied by utilities.   Industrial energy needs can be
 supplied by utilities, but they are identified and added separately and are
 not considered in this manual.
           The  energy requirements for heating depend on the climate and
 vary with  the  season.  Based on the pertinent climate design information,
 the requirements can be estimated.   Climatic information is also used for
 the design  of  thermal protection for  utility lines.
           The  strong seasonal variation in heating requirements and, to a
 modest  extent,  the  variation in electrical requirements, namely for
 lighting,  affect utilities and, therefore, their cost and feasibility.  The
 utilization can be  estimated and used as a basis for selection of the
 appropriate equipment.
 14.1.1     Energy requirements
           The  heating requirements  for buildings are controlled primarily
 by the  outside  air  temperature.  Wind and sun have a lesser, more temporary
 influence.   The  design and construction of a building determines its
 thermal efficiency,  of course,  and  affects its annual heating requirement
 compared with  another building.  For  planning purposes,  typical values can
 be used, based  on the heating index.   The heating index is  expressed in
 degree-days.   The usual  base in 18C.   Table 14-1 lists  typical values for
 residential  heating  requirements.
                TABLE  14-1.   RESIDENTIAL ENERGY REQUIREMENTS
                                  Space        Domestic       Lights and
                                  heat          hot water     appliances
                                 kWh/C d         kWh/d           kWh/d
 Single residence  houses             9              12           12-24
Multi-residence  buildings           6              12           12-24

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                                14-2
          Domestic hot water requirements are nearly constant  throughout
the year.  Table 14-1 shows typical daily requirements which may be
supplied through the heating system or through electricity.  With
electricity, off-peak power can be used to heat water in  individual
accumulators.  With district heating, a low baseload is provided for  the
summer season.
          The typical lighting and appliances requirements of  residences
are also shown in Table  14-1.  The lower values are for summer conditions;
the higher values are for the winter.  The difference is  primarily due  to
lighting requirements which are near zero in the  summer.
          Table 14-1 does not include electrical  requirements  for car
engine heaters, which are about 5 to 10 kWh/d per car during  the cold
season.
          The values for electricity use are typical daily totals.  The
ratio of daily peak to average demand is 2 to 3 for a community.  The ratio
for an individual residence is much higher.
          The design heating system capacity is based on  the  winter design
temperature.  The difference between the heating  index base  temperature and
the winter design temperature gives the number of degree-days  and the
corresponding heating requirements per day.  The  daily peak  load on a
district heating system  is influenced mainly by the effeots  of morning
warm-up after night set-back, and by heating needs during dropping ambient
temperatures, e.g., in the evening.  The ratio of daily peak to average
load is about 1.2.
          The commercial and institutional heat and electricity
requirements are summarized in Table 14-2.  Electricity requirements  are
more cyclical with the time of day than residential requirements.
      TABLE  14-2.  COMMERCIAL AND INSTITUTIONAL ENERGY REQUIREMENTS

Schools, offices
Schools, offices
Shops and retail
Food stores

< 1500 m2
> 1500 m2
stores

Space heat,
Wh/m2/C d
65
65
60
60
Lights and
equipment, Wh/m /d
600
720
850
1400

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                                   14-3
14.1.2    Climate design information
          Climatic design  information  is given  in Appendix  H.
          The heating  index  is a measure of  the  heating  requirements  of
buildings in a particular  location.  Table H-l  gives  the  heating  index  for
various Alaskan communities, Table H-2 for various  Canadian communities.
Degree-days are Fahrenheit.  For conversion  to  degree-days  Celsius, divide
by 1.8.  Figure H-l shows  the heating  index  distribution  across Alaska,
Figure H-2 the distribution  across Canada.
          The design temperatures indicate the  lowest  temperatures  that
can be expected in a particular location and  provide  a measure of the
needed capacity of the heating system.  Table H-3 gives design
temperatures for various Alaskan communities, Tables  H-4  and  H-5  for
Canadian and Greenland communities.  Temperatures are  in  degrees
Fahrenheit.  Figure H-3 shows the distribution  of design  temperatures
across the contiguous  United States.
          The freezing index is a measure of below-freezing (below  0C)
weather conditions and is  used for computing frost  penetration into the
ground.  Frost penetration information is needed to define  the depth  of
water line burial or the amount of insulation necessary for protection.
Figure H-4 shows the freezing index distribution across Alaska, Figure
H-5 across Canada.  Values are based on degrees  Fahrenheit.
          The thawing  index  is a measure of  the  summer climate.   When
it is significantly smaller  than the freezing index,  the  chances  for
permafrost conditions  increase.  In permafrost  areas,  the thawing
index is used to compute the seasonal  thaw penetration.   Figure H-6
shows the thawing index distribution across Alaska, Figure  H-7 across
Canada.
          The mean annual  air temperature is used in  conjunction  with the
freezing index for computing the ground frost penetration.   Figure H-8
shows the mean annual  temperature distribution  across  Alaska.  Table  H-6
gives temperatures for northern Canadian communities.  The  same table
also gives ground temperatures.  Ground temperatures,  including permafrost
temperatures, are typically a few degrees higher than  the mean annual air

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                                 14-4
temperatures.  Alaskan ground temperatures are given  in Table H-7  for
various communities.
          Groundwater temperatures are a good ground  temperature
indicator.  In Alaska, the locations of many thermal  wells  are  known,
even in permafrost areas, mainly because they are artesian.   It is very
likely that there are many more thermal wells (non-artesian)  or
undiscovered aquifers.
14.1.3    System utilization and feasibility
          Electric and thermal utility systems are  capital  intensive.
For electric systems, the generating plants are  the most  expensive part;
for thermal systems, the distribution lines are  most  expensive.   That
means, in turn, that thermal distribution  systems have  a  smaller  range of
coverage  than electric systems, because  they are limited  to higher
density areas.  Dispersed residential areas must use  either delivered  fuel
or they may be able to use off-peak electricity  economically,
supplemented with solar heat.
          To ensure economic feasibility,  the  system  utilization  must  be
as high as possible.  That means that the  amplitude of  the  peaks  and
valleys of the load curve should be minimized.
          With electric systems, this goal can  be achieved  through
various demand management techniques which shift loads  from peak  to off-
peak periods.  Heating of domestic hot water and electric storage heating
are examples of deferrable demands.
          With thermal systems  (district  heating),  the  loads are  governed
by the weather.   Daily demand  fluctuations are  smaller  than the seasonal
fluctuations.  Seasonal  storage  has not  yet been shown  to be feasible.
The demand closely  corresponds  to  the weather,  and  known  climatic data
can be used  to estimate  the  anticipated  plant  utilization.
          The  intensity  of  the  winter weather,  i.e.,  the  winter design
temperature, determines  the  required  plant capacity.   The duration of the
cold weather,  i.e.,  the  heating  index,  determines  the annual plant
output.   The ratio  of  actual annual  output to  possible annual output
(at  full  capacity)  is  the measure  of  plant utilization.  It is expressed
in hours  per year of  equivalent full  capacity  output.  Full capacity is

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                                    14-5
 8760 h/a (hours per annum).  For a district heating system, 2000 to 2500
 h/a is a feasible utilization.
           The anticipated plant utilization is computed from climate
 information by:
              heating index x 24             (h/a)                 (14-1)
           18C - design temperature
           The actual utilization may be only about 90% of the value
 computed from equation (14-1), or less, because the system usually has
 excess capacity,  e.g., to allow for growth and reserve.
           As  an example,  the anticipated utilization is computed for
 Anchorage  Alaska,  and Edmonton, Alberta.  From Tables H-l and H-2 the
 heating  index values are  10789 and 10320 F d, respectively.  The values
 of  -25F and  -39F from Tables H-3 and  H-4 can be  used for the design
 temperatures.   The resulting values for utilization are 2877 and 2381
 h/a,  respectively.  Using 90% to obtain the anticipated actual
 utilization,  the  following values result:
           Anchorage          2590 h/a
           Edmonton           2143 h/a
           Figure  H-10 shows a plant utilization distribution across the
 contiguous  United  States  which corresponds closely to utilization values
 that  result from  the above calculation  method.
           A higher value  for system utilization means that lower density
 areas  may  be  served economically,  other things being equal.
           As  with  electric systems,  it  is  advantageous to have a mix of
 baseload and  peak  load plants.   Baseload plants are characterized by high
 capital  but low energy cost,  for example,  cogenerating plants (heat and
 power).  Peak  load and reserve  capacity plants have the opposite
 characteristics and are used  only intermittently.   Gas turbines  (without
 heat recovery)  are examples of  peak load plants for electricity
 production; boiler plants  are  examples  for heat production.
 14.2  Energy Supply
          Energy supply in  arctic  climates is  similar  to  that in other
climates.  Some methods are employed  to  greater or  lesser degrees due to
aretie conditions.

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                                   14-6
14.2.1    Fuels and storage
          The fuels and storage of  fuels used  in  the  arctic  climate are,
generally speaking, the same as in  temperature climates.   However,  there
are some special design elements which must be considered  to ensure
reliable operation.
14.2.1.1  Selection of fuels.  The  petroleum products (gasoline,  diesel,
etc.) used in arctic climates to power motor vehicles,  trucks and air
craft are identical to fuels used in  temperate climates, except  for
possible octane levels, grades or additives which are controlled  by the
different petroleum producers.
          The one area in which fuel  use varies is in the  use of  diesel
fuel.  The one main property of fuel  oil which is readily  affected  by the
cold climate is viscosity.  Viscosity is the property of a substance
which makes it resist the tendency  to flow.  From Figure  14-1,  it ean be
seen that fuel oil at moderate temperatures of 20F to  60F  has  a
kinematic viscosity of between 9 to 3.5 oentistokes.   But  when  the
temperature drops to arctic conditions of -10F to -60F,  the viscosity
of the fuel oil becomes extremely high, 25 to  500 centistokes.   This high
viscosity presents a problem in that  the fuel  oil becomes  so thick  that
it refuses to flow.  Fuel oil in above-ground  tanks and piping which are
exposed to arctic temperatures often  becomes too  thick for burner pumps
to handle.
          There are several solutions to this  high viscosity problem.
One solution is to bury the fuel piping and storage tank to  avoid
exposure to the cold temperatures.  This is only  practical for  small tanks
of up to 190 nr.  Another solution  is the use  of  arctic grade diesel
fuel, DF-A, which has a much lower  kinematic viscosity. From Figure 14-1,
it can be seen that DF-A fuel has a kinematic  viscosity of 11.4
centistrokes at -30F.  This is a great improvement over other  figures.
14.2.1.2  Storage and transport of  petroleum fuel. The basics  of fuel
storage are the same as those for water storage presented  in Chapter 5.
The most common means of storing large quantities of  petroleum  products,
both in temperate and arctic climates, is large above-ground steel
storage tanks.  The storage tanks used in both climates are  generally the

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-60
              -40     -20
0
 25       50
Temperature C
100
150
200  250
FIGURE 14-1.  KINEMATIC VISCOSITY AS A FUNCTION OF TEMPERATURE FOR VARIOUS FLUIDS.

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                                  14-8
same and are constructed  to  the  standards  set  by  the  American Petroleum
Institute, Standard 650.  The  structural design of  the  tanks, in most
eases, is the same unless extreme  snow and  ice loads  are  expected,  in
which case the structure  is  re-designed to  carry  the  loads.   One major
difference in storage  tank design  in  the Arctic is  the  steel  materials
used.  Standard grade  steel  plates become  less flexible and  somewhat
brittle at extremely eold temperatures.  For  this reason, a  different
grade of steel with good  cold  weather characteristics is  used for tank
construction.  The tank appurtenances also  vary from  temperate to aretie
climates.  Water  in the product  is a  very  serious problem in  any climate,
but in the Arcti it presents  some different  problems.  The  water
draw-off connection on the tank  is used to  remove the water  which
accumulates within the tank.   Because of the  arctic cold, the water
draw-off valve must be a  non-freeze type valve.   The  design  of a
non-freeze valve  is such  that  the  valve seat  is mounted well  back into
the inside of the storage tank,  where the  temperature of  the  product and
water is above freezing.  If a conventional valve is  used, the
probability of water in the  valve  freezing  and cracking it is quite high.
This oould create a serious  problem because when  the  frozen,  cracked
valve thaws out,  fuel  will escape  resulting in a  spill.
          Some storage tanks equipped with vapour-saving  tank breathers
also present problems. The  breathers will freeze up  in cold  weather
unless they are equipped  with  a  flexible frost and  ice resistant diaphragm
material.  The breather screens  also  have  a tendency  to frost shut during
periods of extreme cold.  Therefore,  it is  recommended that  the screens
be removed during winter.
          For the most part, petroleum products are transported by
pipeline, tank trucks, rail  tank oars, and barges on  sea  and  rivers,
whichever proves  to be the most  efficient  and economical.  In some cases,
petroleum products have to be  air  lifted into remote  sites due to the
lack of road or rail service.   In  these oases, the  petroleum products are
transported in drums or flexible bladder tanks.
          Pipelines are probably the  most  efficient way of transporting
large quantities  of petroleum  products.  Arctic  construction of a

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                                  14-9
 pipeline is similar to methods used elsewhere in the world.  There are,
 however, a few problems encountered when routing a pipeline through the
 arctic climate and terrain.  Pipelines are generally not buried in
 permafrost areas because the warm flow of product would melt the perma-
 frost  and the  pipeline would gradually sink in the quagmire slurry
 produced.  If  a pipeline is buried some form of thermal protection must
 be  provided for the permafrost.
           Pipelines in permafrost areas are supported above-ground on
 refrigerated  pile supports.  The refrigerated piles prevent the
 permafrost from thawing, thus providing a solid foundation for the
 pipeline.
           Moisture or water in petroleum products presents a very serious
 problem  when  the product is transported through pipelines or any other
 system where  it is exposed  to freezing temperatures.  The water freezes
 and builds up  by glaciering until a plug is formed.  Damage to valves,
 pumps, and other equipment  could result.  Therefore, it is essential that
 water  be removed from the  product through water separators.  These water
 separators, along with other product transfer equipment, should be
 enclosed in a  heated  shelter to protect the equipment and'provide a warm
 working  area in which to perform routine repairs  and maintenance.
           Transfer components,  which are not enclosed in warm shelters
 but are  used in pipelines and other systems, require cold weather
 considerations  in their  design.  Control valves,  flexible hoses,  meters,
 etc.,  should be designed from materials and components that will  stay
 flexible  and operable at cold temperatures,  such  as polybuthylene
 flexible  plastic  pipe.
 14.2.1.3   Storage and transport of  solid fuels.   The most  commonly used
 solid  fuel  is coal.   The storage  and  transport  of  coal is  virtually the
 same in  both arctic and  temperate climates.   However,  unloading and
 storing  of coal  in  arctic temperatures  presents some problems.  The coal
 is usually washed  at  the mining operation  prior to  loading  into the rail
 oars.  At cold  temperatures,  the  wet  coal  quickly  freezes  into  a  large
rail-ear-shaped  chunk  of coal.   The  unloading area  must  be  enclosed by a
shed type structure built onto  the  power  plant over  the  traeks.  The

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                                  14-10
frozen coal oars are placed  in  the warm  sheltered  area for unloading.
The frozen coal is thawed and unloaded with  steam  probes  and coal car
shakers.  The coal, via conveyor belt, is  then  stored  either in the plant
bins or in piles outside the plant.  When  coal  is  required from outside
storage piles, steam probes, bulldozers  and  loaders  are used to thaw and
move the coal into the power plant storage bins.   Once the coal is inside
the plant, one would think that no other problems  would .exist.   However,
because of the mass involved, the coal is  still quite  eold, contains
moisture and, once allowed to sit, will  generally  refreeze in the bins or
in the ooal chutes on  the way to the boilers.   This  condition is usually
remedied with shakers  attached  to the chutes or bins.
14.2.1.4  Storage and  transport of liquified gaseous fuels.  The most
common fuel of this type used in the Arctic  is  propane gas.  Propane is
transported the same way in  both arctic  and  temperate  climates, in
specially designed pressure  tank cars and  trucks.   Propane is distributed
and stored in small pressure vessels which serve homes and small
businesses.
          The one major problem with propane in the  Arctic is related to
its vaporization characteristics.  Propane,  at  temperatures below -45C,
remains a liquid.  This situation can become dangerous because a liquid
stream of propane is sometimes  allowed to  pass  into  piping leading to
utilities and appliances, causing fires  and  explosions.  Propane tanks
exposed to these eold  temperatures either  require  thick insulation or
enclosure in heated structure.   If a heated  enclosure is used, an
additional problem arises in  that the enclosure must be ventilated to
prevent a build-up of  explosive vapours.  Another  problem with propane at
sub-zero temperatures  is that when  the gas passes  through the tank
regulator and valve, its expansion  causes  a  drop in temperature,
resulting in frosting  and freeze up  of the regulator and valve.
14.2.1.5  Reliability, maintenance,  security.   The reliability of
petroleum product systems in  the Arctic  is basically the same as systems
constructed in warm climates, provided  that  the materials and components
used in the arctic construction are  appropriate to the climatic
conditions.  If arctic design procedures are followed, there should be no

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                                  14-11
problem concerning reliability.  Maintenance of  petroleum  product  systems
in cold regions again does not present any serious  problems.
          Security of petroleum product systems  in  the Arctic  is no
different from temperate climates.  Tank farms,  pump  stations,  etc.,  are
usually manned 24 hours a day and are enclosed with high security
fencing.  Pipelines are inspected regularly by vehicle or  helicopter.
14.2.1.6  Fuel spills and containment.  The probability of a fuel  spill
is virtually the same anywhere in the world.  The largest  cause of fuel
spills is related to human error or negligence of operating personnel.
Large spills generally start out as small leaks  which can  be stopped  or
avoided by performing regular maintenance and inspections.
          Containment of large or small petroleum spills is basically the
same in any climate.  The most common methods of containing and
collecting spills consist of dike areas around tanks, collection weirs in
drainage ditches, drip pans, absorbents, etc.  Dikes  in cold regions  are
generally constructed of gravel and rook with a  layer of impervious local
soil as a liner.  Membrane materials which remain flexible at  low  temp-
eratures, such as PVC and CPE, may also be used.  Concrete dikes are  not
always practical in the North because freeze-thaw action causes cracks in
the concrete walls to the point where spilled fuel  would leak  out.
          Some problems are encountered in dike maintenance and operation
during the winter.  Large snow falls are not uncommon and  they are
usually followed by warm thawing temperatures and rain, which  creates a
quick snow melt situation.  This quick melt produces  large quantities of
water which must be drained from the frozen dikes.  A sump is  usually
provided and a portable pump is used to pump out water which
accumulates.
14.2.1.7  Corrosion and grounding.  Corrosion of petroleum storage and
transport systems in the Arctic presents virtually  the same problems  as
found elsewhere.  Arctic soil and atmospheric conditions vary  from
location to location, some being more corrosive  than  others.   For
instance, those systems whieh are located along  the arctic coast are
exposed to the corrosive action of salt air, whereas  those systems inland
are only exposed to normal conditions.  Soil conditions also vary

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                                 14-12
considerably from one area to another.  Areas containing  peat  bog  are
usually acidic and very corrosive.  Preventative measures  taken  against
corrosive conditions in cold regions are standard measures  used  elsewhere
in the world.  Pipelines are cleaned, primed and wrapped  before  burial.
Storage tanks are protected inside and out with special coatings,  etc.
Cathodic protection measures, magnesium anodes, are  also  used  to help
prevent corrosion of buried product lines.
          The battle against corrosion of steel used  in product  storage
and transfer systems is a universal problem and cold  regions provide no
special problems.
          Grounding of petroleum product systems is  very  important and  is
required in all climatic conditions.  Arctic designs  are  no different
concerning grounding of equipment and product lines  to guard against
static discharge.  In areas without permafrost conditions,  the product
systems, including storage tanks, piping, buildings,  water  lines,  metal
sewer lines, etc., are all bonded together and connected  to grounding
rods whieh are driven into the ground.  In some areas of  the Arctic, the
ground conditions provide good grounding systems.  Some areas  may  require
several ground rods or even a grounding plate set in  a salt solution.
          Permafrost areas present another situation. Areas with
underlying permafrost do not provide acceptable grounding  conditions
due to the high resistance of frozen ground.  In these areas,  everything
is bonded together, including electrical wiring, POL piping, metal
building structures, storage tanks, water and sewer  lines,  etc., to form
one large grid network which can then be connected to a water  well casing
which penetrates the permafrost layer, which in turn provides  an
acceptable ground.  If no well casing exists, then the grid system is
connected to a ground rod which does not penetrate the permafrost.  This
will provide a common floating ground with everything at  the same
electrical potential.  This is acceptable as long as  everything  is bonded
to that common ground.  Another practice is to place  a grounding grid  of
cable into a lake.
14.2.2    Heat and power production
          The boilers and machinery that generate heat and  electricity
are the same in cold regions as in temperate climates.  Special

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                                 14-13
considerations apply to the structures that support and contain  them,
their reliability, their operating characteristics, their
construotibility, and other factors.
14.2.2.1  Central vs. independent generation.  Electricity  is generated
in central plants and distributed in cold regions as in temperate
climates.  The reliability advantages of central plants with multiple
generating units are desirable, but added consideration must be  given  to
achieving corresponding reliability in the distribution network, which is
exposed to the severe climate conditions.  The same holds true for
heating plants within the feasible distribution limits, even more so than
in temperate climates:  heating needs are greater, favouring the eoonomie
benefits of district heating; the greater reliability is a  vital factor;
and fire safety is enhanced by the elimination of combustion equipment in
every building.
14.2.2.2  Cogeneration.  Whenever heat is generated, particularly for  low
temperature uses such as space heating, the simultaneous generation of
electricity should be considered because most electricity is generated
from heat.  Conversely, whenever electricity is generated,  the
utilization of the waste heat should be considered.  The advantage of
cogenerated electricity is the high fuel efficiency it attains compared
with single-purpose generated electricity.  The amount of cogeneration
that is feasible is determined from an analysis of the thermal and
electrical loads supplied by the central plants, the output
characteristics of the generating equipment, and the ability to  store
output (e.g., heat) for load management.  Typical generating efficiencies
of different types of plants are summarized in Figure 14-2.
14.2.2,3  Strategic considerations.  These are influenced not only by  the
severity of the climate and the possible difficulties with  logistics due
to remoteness, but also because the isolation of most installations or
communities requires a greater degree of self-sufficiency than with
interconnected systems.  Diversity should be built into the system so
that alternate fuels can be used.  Redundancy of equipment  as well as
standby capacity must also be considered.

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                             14-14
                       63
                       33
                              23
                                     1-75:
                                            120;
                               25
L_J
W77A
 BCD

Exhaust
Auxiliary losses
Waste heat
District heat
Electricity
                           40  Value in percent
                                                    30
                                                    35
                                      35
                                                    H
                                                   35
             A.  Fossil fuel steam turbine power plant.
             B.  Fossil fuel steam turbine heat and power plant.
             C.  Fossil fuel heating plant.
             D.  Nuclear steam turbine power plant.
             E.  Nuclear steam turbine heat and power plant.
             F.  Gas turbine generator.
             G.  Gas turbine with heat recovery.
             H.  Diesel engine generator.
             J.  Diesel engine with heat recovery.
FIGURE 14-2.
OUTPUT CHARACTERISTICS OF  VARIOUS  COMMON ELECTRIC
GENERATING SYSTEMS.   The output  called  "District Heat'
represents recoverable thermal  output in the
temperature range of 80 to 120C.

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                                   14-15
14.2.2.4  Electric generating plants.  Hydroelectric  plants  are
independent of fuel logistics problems and have  the possible added
advantage of providing pumped hydro  storage  in conjunction with
eogeneration.  They use renewable resources.  In  cold  regions,
hydroelectric plants may be limited  by icing  or  seasonally reduced
output.  Large thermal eleetrie  plants are typically  baseload plants;
they are also likely candidates  for  eogeneration.   Smaller units, usually
for peak load and reserve, may be gas turbine or  diesel  engine
generators.  They require special consideration  in  the design of air
intakes and filters to avoid congestion by snow.  This is achieved  by
installing a heat exchanger in the intake plenium to  sublimate  the  snow
or melt any possible ice build-up.   It is not sufficient to  depend  on
open doors or windows in a generator building for air  intake.  The
combustion air requirement for diesel engines is  about 3 std. m-Vh
                                             n
per kW, and for gas turbines about 55 std. mj/h  per kW output.   Use
of wind energy, such as a vertical axis wind  turbine,  is limited by icing
problems that would be encountered on the turbine blades.
14.2.2.5  Heating plants.  Fuel  burning heating  plants,  also called
boiler plants, are low cost plants but the heat  output is relatively
expensive because the cost of the fuel is high (fuel  oil or  natural gas),
and because electricity is not co-produced to offset  the fuel cost.
Therefore, boiler plants are typically peak  load  and  reserve plants.
Figure 14-3 shows how the overall cost is minimized by combining a
baseload plant with high first cost  but low  operating  cost with a peak
load plant with lower first cost but higher  operating  cost.   The baseload
plant is efficient at high utilization rates (above 4000 h/a in the
example), the peak load plant at low utilization  rates.   Boiler plants
burning coal, peat, or solid waste have lower fuel  costs but higher first
costs.  They are more like baseload  or intermediate load plants.
          When an indigenous source  of low-temperature heat  is  available
for utilization through heat pumps,  it offers an  alternative with the
important advantage of independence, particularly when the electricity
used for the heat pumps is also  generated from renewable resources.
Examples of low-temperature sources  are ocean water, with year-round

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    $    __$__
  kWa   MWh
                                14-16
                   Specific energy cost at optimum utilization
                                             8x 103h/a
                  30 + 0.009 h/a
                                    60 + 0.0015 h/a
                               i     i    i	i	i
        // Peak load
        V///////M
                                  Optimum plant size
                                            The specific annual cost curves of
                                            two different generating plants
                                            intersect at an abscissa value
                                            which determines the cost
                                            effective utilization of the plants
                                            and their respective sizes from
                                            the normalized load curve.
                                             8x 103h/a
FIGURE 14-3.
DETERMINATION  OF OPTIMUM COST AND PLANT  SIZE FOR BASE AND
PEAK LOAD GENERATING PLANTS.  The specific annual cost curves
of two different generating plants intersect at the abscissa
value which determines the cost-effective utilization of the
plants and their respective sizes from the normalized load
curve.

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                                   14-17
temperatures of at least about 5C, and groundwater (hydrothermal
sources), with those same minimum temperatures.  Higher  souree
temperatures are advantageous because the coefficient of  performance
depends also on the temperature of the heat output; lower  output
temperatures permit a higher coefficient of performance.   For example,
with a source water temperature of 10C and a delivery water temperature
of 60C, a coefficient of performance of about CP = 2.6  can be  expected.
That means that for each unit of electric energy used to  drive  the  heat
pump, 2.6 units of thermal energy are delivered, while 1.6 units of
thermal energy are extracted from the source.  If only 50C is  required
or, if instead the source temperature is 20C, then the  coefficient of
performance approaches CP = 3.0.  Suitable sea water temperatures are
found along the coast of eastern Alaska (east of Valdez)  and the west
coast of Canada (see Figure 14-4).  Suitable ground water  temperatures
are found in southwestern Canada.
14.2.2.6  Alternate energy sources.  Alternative indigenous sources of
heat and electrical power generation are being seriously considered for
many northern locations.  Although the benefits in terms  of economics and
self-sufficiency are attractive, the technical and climatic limitations
are often greater in northern locations.  For example, the use  of solar
energy is limited by the shortness or absence of daylight  hours during
the winter.  Also, the use of wind generators may be limited by icing
conditions.
14.2.2.7  Storage.  Hot water accumulators for heat distribution,
providing load management capability and reserve capacity, are  feasible
in relatively larger sizes in cold regions than in temperate climates
because heating loads are greater and because greater reserve capacity
requirements are desirable.  Figure 14-5 illustrates a storage
accumulator.  Large insulated accumulator tanks do not have to  be inside
buildings but the connecting lines and valves must be sheltered and
protected to reduce the danger of freezing.
14.2.2.8  Waste heat.  All electricity generated from heat has  also
"waste" heat as a byproduct, as stated by the Second Law of
Thermodynamics.  This waste heat is unavailable to the process  and

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U-18

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                                   14-19
                      Diffuser
                           Discharging
                            Charging
                                                 Charging
                                            Discharging
                                              -Insulation
                                              - Water tank
                                            Centre of interface
                                             (charge level)
                                            Charging
                                               Discharging
 FIGURE  14-5.   HOT WATER ACCUMULATOR  FOR  THERMAL STORAGE SHOWING  TYPICAL
                INTERFACE CHARACTERISTICS
represents  usually about twice as much  energy as that converted to
electricity (Figure 14-2).  In ease of  a  steam turbine, the condenser
heat is  produced  at a temperature which is  too low for space heating.   If
a higher back  pressure is used or steam is  extracted before the last
stages,  then it is less a case of waste heat  utilization than a
modification for  cogeneration.
          Gas  turbines provide heat from  compresser intereooling  and  from
exhaust  gases  (after recovery for air preheating)  at temperatures which
are suitable for  district heating.  Diesel  engines provide heat from
jacket cooling  and exhaust gases which  is also suitable for district
heating.  In these cases, cogeneration  is possible using rejected "waste"
heat without process modification.

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                                 14-20
          Heat is recovered from exhaust gases from producing  hot  water
or steam with an economiser.  This is basically a water  tube boiler
without combustion chamber.  Frequently, a boiler has an  economiser  built
to its back end for feed water preheating.  When the economiser  is
combined with a gas turbine or diesel engine, the engine  serves  as
combustion chamber and the economiser is the boiler.  Jacket heat
recovery from the diesel engine is with a water-to-water  heat  exchanger
connected to the engine cooling loop.  Such heat recovery boilers  and
heat exchangers are standard equipment.
          To recover heat from exhaust gases from a boiler or  a  gas
turbine for preheating combustion air, gas-to-gas heat exchangers  are
available in the form of plate or tubular air preheaters, or Ljungstrom
rotating cylinder air preheaters.
          The low-temperature heat, at 20 to 30C, from  a typical  steam
turbine condenser is useable for such applications as municipal  water
supply heating, including storage, and sidewalk, street  or runway  heating
for snow and ice control.  The advantage of using low-temperature
heat is its low cost (low economic value) and frequently its great
abundance.
          Waste heat which cannot be used must be dissipated.   The
equipment required to dissipate waste heat represents a  cost which must
be considered when evaluating  the cost of equipment  for  utilizing  it.
Also, the environmental  impact of the waste heat must be considered.
14.2.2.9  Environmental  impact.  The thermal modification of a river or  a
lake due to condenser heat dissipation from a steam  power plant  may  be
either detrimental or beneficial to aquatic life.   In any case,  it will
cause more open water during  the winter, and  increased  fog formation.
The same results  from artificial cooling ponds.  Open water cooling  is
restricted in cold climates, even when abundantly available, and cooling
towers must be  used.  Wet cooling  towers will also  frequently  cause  fog
problems; therefore, dry cooling  towers or wet/dry  cooling towers  must be
used.  Cooling  towers are more  expensive  than taking  available water from
a  stream and usually more expensive  than constructing  a cooling  pond.

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                                   14-21
Wet cooling towers are smaller and less expensive  than  dry  towers  but  dry
towers have no adverse environmental impact.
          Fog and air pollution  problems are greatest in  low lands or
valleys, particularly river valleys.  Therefore, a  power  plant  is  best
located away from a valley or at least downstream  from  a  community to
avoid contributing to air pollution problems.  When  a power plant  must be
located in a low area, its chimney must be especially high  to lift the
exhaust gases above the inversion and fog levels that occur normally
during the winter.  A concentric chimney and cooling tower  (i.e.,  chimney
inside of cooling tower) can improve lofting of the  pollutants  and reduce
the visible smoke plume.
14.2.2.10 Foundations.  Permafrost presents special  requirements for
foundations, different from those in seasonal  frost  areas.   Foundations
of buildings containing machinery must also take into account vibration
in the design.  Since foundations can shift in permafrost or severe
seasonal frost areas, the following measures should  be  taken:
          a)  Each boiler should be on a rigid slab  with  provisions for
              levelling.
          b)  Turbine and generator or engine  and generator units  should
              be on a common rigid slab with provisions for levelling.
          o)  Ducts and pipes should be routed overhead in  the  structure
              and suspended to provide freedom for  independent  movement.
          d)  Points of transit of ducts, pipes and  conduits  through
              building walls should be flexible so  that swing movement is
              possible on both sides of the wall.
          e)  Floor drains should lead into appropriate containments for
              separation of water from oils, etc.
          Where earthquake resistant designs are necessary,  such design
features are basically compatible with and similar  to the above
requirements.
14.3      Energy Distribution
          The distribution of various energy forms  in the Arctic is
similar to methods in other climates.  However, many problems which are
unique to the Arctic require use of special equipment and techniques.

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                                  14-22
14.3.1    Electric power distribution
          The distribution of electric power in arctic and  subarctic
regions is generally similar to those practices which have  also  proven
safe and economical in temperate climates.  The specific  environmental
considerations related to extreme low temperatures, snow, ice, wind,  and
permafrost are the important factors that the designer, contractors,  and
maintainers of electrical distribution systems must be concerned with.
14.2.1.1  Distribution methods^  Both aerial and underground methods  of
electrical distribution have been successfully used.  Wood  pole  lines,
and both self-supporting and guyed metal towers have been used for  high
voltage transmission and distribution lines.  The design  of foundations
for these structures in localities where seasonal frost and active  layers
vary is of prime consideration.  Foundation soils must be carefully
evaluated.  Underground distribution methods must employ means to
stabilize, equalize, and protect buried cables from mechanical damage.
Non frost-susceptible materials must be used in all pads, foundations,
and trenches for electrical distribution systems.  Utilidors and duct bank
systems, if used, must be reinforced to withstand structural displacement.
Prime consideration should be given to placing structural gravel and  non
frost-susceptible material pads on top of the active freeze-thaw layer,
effectively burying cables above the existing or surrounding ground level.
Surface laid wood utilidors placed on gravel pads have also been used
successfully.
14.3.1.2  Aerial.  Aerial electrical distribution systems should be
selected and designed for the basic economic factors that normally  dictate
standard voltage, conductor, transformer, and substation  sizes.  Increased
safety  factors which consider the extremes of the climate  are the
important parameters to consider.  Extreme wind chill factors make  routine
repairs "slow".  Simplicity of construction is essential.
          Additional structural, conductor, and apparatus strengths are
required where severe wind, snow, ice loads, and low temperatures are
anticipated.
          Indoor/outdoor modular apparatus designs are desirable where
severe weather conditions are anticipated.  Cable terminal  buildings, sub-

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                                   14-23
 stations,  and power transformers should be designed to protect equipment
 from the  elements.   Snow sheds,  frost shields,  and windbreaks are
 desirable  features  wherever possible.  Localized heated compartments
 within  larger structures in substations are helpful and provide the
 necessary  ambient temperatures  for standard apparatus.
           In  aerial distribution construction,  wood poles have been set
 into the  permanently frozen soils during the cold season when the top
 active  zone is  also frozen.  This permits easier construction on and
 across  tundra,  swamp,  and small  pond/lake areas.  Specifications for pole
 depth settings  have generally used the  gravelly soils  criterion of 10
 percent pole  length plus another additional four feet  (e.g.,  50-ft poles
 set  9 ft).  These wood pole structures  were in  the average range of 50
 feet, classes 2 to  4.
           Consideration can also be  given to "tripod"  pole configuration
 without pole  burial;  gravel-filled oil  drums or rock-filled cribbing will
 provide stability.   For camp distribution systems, masts supported on the
 buildings  can serve to distribute secondary power, a common practice in
 Europe.
 14.3.1.3   Underground.   Underground  electric power distribution systems
 should be  selected  and designed  with the same economic factors relevant
 to the aerial  system,  i.e.,  voltage,  ampacity,  and loss considerations.
 In addition,  the  flexibility of  cable insulations and  jackets are
 important  factors where extreme  low  temperatures are found.
           Both  primary (above 600V)  and  secondary cables  must be
 installed  so  that bends,  tensions, splices,  and  terminations  are properly
made.  Underground  distribution  standards  that  cover such items as the
grounded neutral  insulation ratings,  basic  impulse levels (BIL), and
corona extension  levels,  etc., are available to  the designer.
Construction may  warrant  special  conditions  and  additional  safety
factors. Lines  should  be  placed  below the  seasonally active depth.   Table
14-3 provides a comparison  of rubber  and  plastic  compounds.   Figures  14-6
and 14-7 illustrate items considered  of  prime importance  for  both under-
ground and overhead aerial  systems.

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                                                      14-24
                        TABLE  14-3.   RUBBER AND PLASTIC  COMPOUNDS  COMPARISON


Rubber Insulation



Oxidation Resistance
Heat Resistance
Oil Resistance
Low Temperature Flexibility
Weather, Sun Resistance
Ozone Resistance
Abrasion Resistance
Electrical Properties
Flame Resistance
Nuclear Radiation Resistance
Water Resistance
Acid Resistance
Alkali Resistance
Gasoline, Kerosene, Etc. (Aliphatic
Hydrocarbons) Resistance
Benzol, Toluol, Etc. (Aromatic
Hydrocarbons) Resistance
Degreaser Solvents (Halogenated
Hydrocarbons) Resistance
Alcohol Resistance
SBR
(Styrene
Butadiene)



F
F-G
P
F-G
F
P
G-E
E
P
F-G
G-E
F-G
F-G

P

P

P
F
Natural





F
F
P
G
F
P
E
E
P
F-G
G-E
F-G
F-G

P

P

P
G
Syn-
thetic
Natural



G
F
P
E
F
P
E
E
P
F-G
E
F-G
F-G

P

P

P
G
Poly-
buta-
diene



G
F
P
E
F
P
E
E
P
P
E
F-G
F-G

P

P

P
F-G
Neo-
prene




G
G
G
F-G
G
G
G-E
F
G
F-G
G
G
G

G

P-F

P
F
Hypalon
(Chloro-
sulfo-
nated
Poly-
ethylene
E
E
G
F
E
E
G
G
G
G
G-E
E
E

F

F

P-F
G
NBR
(Nitrile
or Buta-
diene
Acrylo-
nitrile)
F
G
G-E
F
F-G
P
G-E
P
P
F-G
G-E
G
F-G

E

G

P
E
EPR
Ethylene
Propy-
lene
Rubber

G
E
F
G-E
E
E
G
E
P
G
G-E
G-E
G-E

P

F

P
P
Butyl





E
G
P
G
E
E
F-G
E
P
P
G-E
E
E

P

F

P
E
Silicone





E
0
F-G
0
0
0
F
0
F-G
E
G-E
F-G
F-G

P-F

P

P-G
G

Plastic Insulation

Oxidation Resistance
Heat Resistance
Oil Resistance
Low Temperature Flexibility
Weather, Sun Resistance
Ozone Resistance
Abrasion Resistance
Electrical Properties
Flame Resistance
Nuclear Radiation Resistance
Water Resistance
Acid Resistance
Alkali Resistance
Gasoline, Kerosene, Etc. (Aliphatic
Hydrocarbons) Resistance
Benzol, Toluol, Etc. (Aromatic
Hydrocarbons) Resistance
Degreaser Solvents (Halogenated
Hydrocarbons) Resistance
Alcohol Resistance
PVC
(Poly-
vinyl
Chloride)
E
G-E
E
P-G
G-E
E
F-G
F-G
E
P-F
E
G-E
G-E

G-E

P-F

P-F
G-E
Low-
Density
Poly-
ethylene
E
G
G-E
G-E
E
E
F-G
E
P
G
E
G-E
G-E

P-F

P

P
E
Cellular
Poly-
ethylene

E
G-E
G-E
E
E
E
G
E
P
G
E
G-E
G-E

P-F

P

P
E
High-
Density
Poly-
ethylene
E
E
G-E
E
E
E
E
E
P
G
E
G-E
G-E

P-F

P

P
E
Poly-
propylene

E
E
E
P
E
E
F-G
E
P
F
E
E
E

P-F

P-F

P
E
Poly-
urethane

E
G
E
G
F-G
E
0
P-F
P
G
P
F
F

F

P

P
P
Nylon


E
E
E
G
E
E
E
F
P
F-G
P-F
P-F
E

G

G

G
P
Teflon


0
0
0
0
0
E
G-E
E
0
P-F
E
E
E

E

E

E
E
P  =  poor
E  =  excellent
=  fair      G =  good      These ratings are based on average performance of general purpose
     0   =  outstanding      compounds.  Any given property can usually be improved by the use
                          of selective compounding.

-------
                                       14-25
INSULATOR
 CONDUCTOR
                                            Alternate method for
                                            dead end assembly
      STRUCTURE
                     
      Freeze/thaw zone

         Permafrost

      FOUNDATION
Foundation - Recommend polyethylene pole "blanket" and/or non-frost
         susceptible materials in active zone. In permafrost, 10% +
         1.2 m for pole setting depth
         Favor wood pole when less than 60 ft. for helicopter setting.
         Safety factors considered.
         In low rain arctic areas use extra dead end suspension bells
         to reduce contaminant flashover. Recommend tongue and clevis
         for suspension assembly.
Conductor - Standard ACSR sizes: Secondary insulated/low temperature
         flexibility.
                   FIGURE 14-6.  OVERHEAD AERIAL
        DIAGRAMETRIC-CABLE SYSTEM     SECTION VIEW OF PAD OR ROADWAY
               TERMINATIONS
          II
        SPLICES
     INSULATION/JACKET
                            Cables buried in
                             toe of roadway


        Gravel pad -\   [Roadway *j
                     % XJ.l fl- ....'.'  . U- ' '' "T^^^TT^ M
                I     v^^^i** tf"*?.' ' t9"Q"V,** "   *." f ".,' * 'J
                                               Active layer
                                                          .
                              Freeze/thaw zone
                         Permafrost
         Recommendations
         Insulation/Jacket - Low temperature flexibility favor solid dielectrics, and
                          ethylene propolene types.
         Splices - Manufacturers kits, instant slip-on terminators to eliminate pouring
                hot compounds, and building taped stress cones in field.
         Terminations-  Taped stress cones in field.
                   FIGURE 14-7.  UNDERGROUND CABLE  GUIDELINES

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                                   14-26
14.3.1.4  Special considerations.  There are certain  special
considerations and problems that pertain to construction of electric
distribution utilities in cold regions.  These are not necessarily
impossible to solve but require care and thought in the selection of
materials, methods of installation, and followup maintenance.
          A general list of items is as follows:
          1)  Nylon jacketed conductors (types THWN).  When used at low
              ambient temperatures, the insulation tends to separate  from
              the jacket.
          2)  Cold weather starting of gaseous discharge lighting.
              Mercury vapour type is especially hard  or impossible to
              start.  Ballast low-temperature ratings must be  checked  for
              minimum starting temperatures; otherwise luminaries must
              remain energized continuously during extreme lows or
              provided with integral thermostats to start luminaries  when
              the temperature drops below -30C, the  present low limit  of
              ballast manufacturers' ratings.
          3)  Molded ease circuit breakers and stored potential switches
              are not 100 percent dependable at extreme low ambient
              temperatures.  The alternative use of fuses and  an adequate
              supply of spares must be evaluated, or  supplemental heat
              provided to raise the ambient temperature of the equipment
              enclosure.
          4)  Pole jacking occurs when frost heaves and soil freeze/thaw
              conditions displace alignment of overhead pole lines.
              Polyethylene pole blanket sleeves have  been specified and
              used for some utilities.  A pole sleeve of 10 mil black
              polyethylene can be slipped over the base of the pole and
              sealed moisture tight.  This permits seasonal frost heaving
              without pole jacking.  The plastic double-walled sleeve
              prevents frost bonding to the wood pole surface.
          5)  The resistance of grounding electrodes  and earth grounds  in
              frozen soils varies according to the temperature.  Aretic

-------
                       14-27
    research papers by the U.S. Army Cold Regions Research and
    Engineering Laboratory (CRREL) have treated this subject [1].
6)  Cold-temperature special alloy steel is being specified for
    transformers, circuit breakers, and other exterior electrical
    distribution apparatus and specifications for equipment
    subject to extreme low temperatures is described in
    reference [2],
7)  Aerial conductor vibrations, aoelian and galloping.  Arctic
    environments, especially near coastal regions, present
    unpredictable storm combinations that make normal service
    access impossible.  The extreme low temperatures mandate
    critical evaluation of mission objectives.  Power
    interruptions of several hours may result in building
    freeze-ups.  Added safety factors must be applied.
    Consideration should be given to the use of steel
    conductors to provide melting of ice on conductors, or the
    use of strain gages on conductors to sense critical ice
    loading and sound an alarm or pre-schedule line "short-
    circuiting" to melt ioe.  All deadend primary insulators
    should be tongue and clevis type.  Reliance on cotter keys
    alone is inadequate.  All pole-mounted hardware should be
    nut and cotter key to nut and "pal" lock-nut.
         Aeolian vibration control is covered in Stockbridge
    [3], and dumbell torsional dampers plus armor rods should
    be used at all primary cable conductor supports.
    Cataclismic failures are not associated with aeolian
    vibrations.  Frequent conductor inspection is required to
    identify areas of severe conductor fatigue to prevent
    conductor failure.
         The "galloping" conductor phenomenon is endemic to all
    areas.  In general, conductor spacing must allow for
    elliptical loop dancing in the single conductors to prevent
    short circuit phase-to-phase faults.  Mechanical

-------
                                  14-28
              considerations, however, present the greatest area of
              challenge.  It is not possible with the present
              state-of-the-art to eliminate "galloping".  In severe
              galloping areas, conductors should be dead-ended at each
              pole, or preferably the transmission line should be
              rerouted or an underground cable routing selected.  Dense
              cold winds from glaciers and ice fields have been known to
              reach velocities of over 300 km/h near the sea, coincident
              with 152 mm of radial ice [4],  Catastrophic mechanical
              damage to towers, insulators, and hardware can be minimized
              by the use of slack spans in relatively short runs of 90 m
              or midspan spacers in longer runs of up to 300 m.
          In general, cold regions do not always have a recorded history
of meteorological data upon which to base a pole/tower line design.  For
this reason conservative design must be used.
14.3.1.5  Reliability, maintenance, and security.  Reliability of
electric power distribution is the norm rather than  the exception.  If
the major items offered in the previous paragraphs on special
considerations are acknowledged and the weak  links are eliminated,  then
reliability is measured further by adoption or use of the  following
individual job features:  dual feeders, loop/radial  circuits, parallel
transformers, dual busses, additional switohgear and generation units.
These all add up to planned reliability.
          Maintenance is enhanced by enclosing complex apparatus  in
modules or enclosures where  the cost of such  structures warrant  their
use.  Consideration should also be given  to providing "line-men" weather
shelters with emergency survival gear in  inaccessible areas.  Helicopter
access is not predictable and  ground  crews  in all-terrain  vehicles  may  be
required to make emergency  repairs in nonflying weather conditions.
During helicopter  operations,  rather  than  use standby time,  options are
usually for return piek up.   Sudden weather changes  have  isolated  line
crews for as long  as  a  week  [4],   Buried  multiplate  steel  culvert
storerooms have been  considered  expedient  in  instances  where  fast,

-------
                                   14-29
efficient helicopter supported erews must work many miles  from  larger
warehouses.  If an area is a severe environmental hazard or has a  low
safety factor then, for example, spare insulators, hardware, and
accessories may be kept looked and secure from the elements.
          Security is usually handled with scheduled maintenance and
inspection trips.  "Flying the line" or overland inspection trips  are
considered most expedient where daylight in the Arctic- is  reduced.  When
darkness prevails, operation, maintenance and security lighting becomes
an important factor.  Vehicles equipped with inspection lights and/or
banks of auxilliary lighting and standby generators for power are
considered important.  Small helicopters equipped with high intensity
spot/flood lights are being used for security and maintenance
purposes.
14.3.1.6  Communications lines.  Design, construction, operation and
maintenance of communications lines in cold regions are considered
standard practices of 'outside plant work'.  Until recently long haul
communications in the Arctic have been via tropospheric radio and
microwave methods.  Satellite communication is now being used for  some
remote military and civil bush communications links.  Communications at
remote sites, villages, military encampments, experimental and operation
stations are normally handled by telephone or radio telephone equipment.
In these locations standard local telephone exchange equipment practices
are used.  Outside plant overhead and underground installations are
usually constructed during the summer months.  Protection  of overhead
lines and underground communications systems from failure  presents the
same mechanical/electrical environmental problems as with  electric
distribution.
14.3.2    Heat distribution
          Heat distribution networks in cold regions require particular
attention to the seasonally restricted conditions for construction, and
the influence of frost on operation and maintenance.  The  greater  heating
needs in cold regions enhance the feasibility of providing district
heating.  Minimum density limits of 15 to 25 MWh/km^ are typical of

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                                 14-30
Swedish district heating experience.  This corresponds to about four
residences per acre.  The lowest densities can be served economically
where they are an expansion of an existing system or where a residential
area is adjacent to a trunkline leading to another large area being
served.  Another factor influences the feasible density limit:  a coastal
climate location with a long heating season but without extremely cold
weather will provide a greater system utilization (more equivalent  full
load hours) than a continental climate location with its greater
temperature extremes and will, therefore, make lower load densities
feasible.  For example, in Sweden and Finland, the typical system
utilization is 2000 to 2500 h/a; in  Iceland, it is nearly 4000 h/a.
14.3.2.1  Temperatures and fluids.   It is principally advantageous  to
use the lowest practical fluid temperatures for heat distribution because
losses and total costs are minimized.  The temperatures required inside
the building for heating purposes are usually no more than 80C during
the coldest weather, and less during milder weather.  Heating  systems
requiring supply temperatures not exceeding 50C and even less are  being
built.  Temperatures over 100C are  only needed in special  situations
such as in buildings with process heat requirements.  These may be  met
more economically with auxiliary heating equipment than by using high
temperature distribution throughout  the whole  system.
          Water has important advantages over  steam  for heat
distribution.  Low  distribution temperatures are  possible;  both
temperature and flow rate can be varied  to  permit  almost  infinite
delivery modification; the ability  to operate  with low  temperatures
minimizes heat losses and permits more  pipe material  alternatives;
thermal  storage facilities can be readily  incorporated  into  the  system
because water  itself is  an efficient storage medium.
          A glycol-water  solution can be used  instead  of  plain water for
freeze-prevention,  e.g.,  in  an  intermittantly  operating  system.   The
disadvantages  of  the glycol  solution are greater  viscosity and lower
specific  heat  than  water, resulting in  greater pipe  size,  fluid  cost and
pumping  power  requirements.

-------
                                  14-31
 14.3.2.2  Buried distribution piping.  This concerns directly buried,
 insulated  piping.  A wide variety of insulating methods or pre-insulated
 pipe  systems  are being used.   Figure 14-8 shows examples of the principal
 types of systems being used.   Their selection and applicability depends
 somewhat on the  soil moisture conditions.  Directly buried piping is less
 expensive  to  install than piping in conduits but its service life
 expectancy is also  less.
           The primary distinction is between installations in seasonal
 frost areas and  permafrost areas.  Within these areas there are
 considerations based on the frost-susceptibility of the soils.  Peat,
 clay  and silt are frost-susceptible soils;  they retain large amounts of
 water.   Sand, gravel and  rock are non frost-susceptible;  they drain the
 water.   Frost penetration is  deepest in the least frost-susceptible soils
 and under  snow-free  areas.
           In  seasonal frost areas it is always  safe to place the piping
 below the  seasonal  frost  depth (Figure  14-9A).   Shallow burial is less
 expensive.  In non  frost-susceptible soils  it can be accomplished without
 special  measures  (Figure  14-9B).   In frost-susceptible soils a frost
 shield must be added (Figure  14-9C)  to  prevent  heaving and rupture of the
 lines.   Installation on grade  is  less expensive than burial  and  is
 efficient  where  it causes  no  interference.   The soil cover provides
 protection  (Figure  14-9D).  The  frost shield  protects from heaving in
 frost-susceptible soils and from  excessive  cooling  in non  frost-
 susceptible soils.   Elevated  construction may be  necessary in some areas
 where obstacles,  high groundwater  or other  reasons  make  it necessary
 (Figure  14-9E).
          The  purpose  of the  frost  shield is to  prevent  the  soil under
 the pipes from freezing and heaving.  The water  in  the  pipes  themselves
 is hot and  protected,  as opposed  to  cold  water  pipes,  which  are  not
 insulated themselves,  and  depend  on  the  shield  for  protection.   The  heat
dissipation from  the  insulated hot water  pipes  is greater  than from  bare
cold water  pipes.  Therefore, more extreme  frost  conditions  can  be
encountered than with  cold water  pipes.   In fact, cold water  pipes can be
protected by co-location with the heat distribution  pipes.   The  most

-------
                                       14-32
                         Conduit pipe
                         Insulation
                         HW Pipe
 B
                                                                   Steel carrier pipe
                                                                   Fiber reinforced polyester pipe
High density polyethylene cover
High temperature polyurethane foam insulation
   Vapor permeable water barrier
    Insulating concrete
    Drain pipe
    Structural concrete base
' '>.' o
                           Steel or copper carrier pipe
                        '   Polyurethane or
                           glass fiber insulation
                           High density polyethylene jacket
 A.   Pipe-in-pipe  system.  Supply and return service  lines  in common
      conduit pipe.

 B.   Individual  pipe-in-pipe  main distribution  lines.

 C.   Pre-insulated  distribution piping with integral  extruded jacket.

 D.   Pre-fabricated insulating culverts  for slip-on assembly.

 E.   Cast-in-place  insulating concrete block.


         FIGURE  14-8.   DIRECTLY BURIED HOT WATER DISTRIBUTION PIPING

-------
 fs

U>
Co

-------
                                 14-34
severe exposure is in the case of pipes on grade under a berm (Figure
14-9D) because it is desirable to keep the berm height to a minimum.   The
dimensions of the U-shaped frost shield can be determined by the method
given by Gundersen [5] and illustrated in Figure 14-10.  The
determination is based on soils of sand and gravel which experience
greater frost penetration than clay and silt.  Figure  14-10 applies only
to non frost-susceptible soils.
          In permafrost areas, direct burial is possible in non
frost-susceptible soils.  A thaw zone develops around  the pipes (Figure
14-11A).  A drain pipe is necessary if burial is shallow so that the
seasonal thaw depth reaches the thaw zone around the pipes, permitting
surface water to drain into it.  In frost-susceptible  soils a thaw shield
is necessary to avoid instability problems (Figure 14-11B).  Trenching in
permafrost requires appropriate equipment for cutting.  This cost  is
avoidable where on-grade installation is acceptable.   A thaw shield is
necessary to avoid soil thaw instability and water accumulation (Figure
14-11C).  The soil cover provides protection.  Elevated construction  is
possible where necessary in all soils, as in seasonal  frost areas  (Figure
14-11D).
14.3.2.3  Distribution piping in conduits.  Conduits include all kinds of
utilidors, culverts and ducts, whether below or above-ground.  They are
discussed in Section 8.  The piping is installed in  the conduit on
supports using either preinsulated pipe or insulating  it separately after
installation.  The installation is basically the same  as inside a
building.  There must be fixed-point supports and also sliding supports
to allow movement due to thermal strain of the pipes,  as well as for
movement of the conduit due to frost (or seismic) action.   In large,
walk-through utilidors the piping is accessible for  installation and
maintenance at all times.  Smaller buried ducts are  only open during
installation with normal access subsequently limited to manholes.
Elevated ducts can be made with removable side panels  for later access or
installation of additional lines.  A buried duct with  its top at ground
level can be made accessible through removable cover plates; the top
surface can serve as a walkway.

-------
                                    14-35
                                Insulation thermal resistance (m2K/W)
                                	 1.4   50mm 1  Extruded
                                	2.1    75mm  >  polystyrene foam
                                	2.8  100mm J
                                                  Freezing index (h.C)
                                                        40000     60,000
                                                         j.	L	1
              4.0   3.0   2.0   1.0
                 Insulation width (m)
FIGURE  14-10.  DIAGRAM FOR  DETERMINING THE REQUIRED INSULATION FOR FROST
                PROTECTION OF  SOILS AND PIPELINES
                Source:  P.  Gundersen, Norwegian Building Research Institute [5].

-------
                                  14-36
       .'D.

                   Seasonal thaw depth
                                                                          Earth berm
                                                                          Insulation
                                                                \   Seasonal thaw depth
                                         OPC '
VL.
                      Drain pipe to sump

Gravel
and /or sand
Insulation
Drain pipe to
(p^
'':';:  Baekfijft
' .-/I'- $$%1%!<&
'U[g) (ojl
^z
sump  '
Sea:
L.i .
^

5onal thaw depth "? ; v '';?
0C 	 r.
-oc "'"''
D





(01
i
V V
'*& 
?! ' Seasonal thaw
L
\ 	 Pipe sleeve
frost heave p
depth
rotecti
 B
A.  Deep or shallow  burial  in non frost-susceptible soils.

B.  Shallow or deep  burial  in frost-susceptible soils.
C.  On-grade installation with earth cover on frost-susceptible  and
    non frost-susceptible soils.
D.  Elevated installation over all soils.
FIGURE 14-11.   INSTALLATION OF HEAT DISTRIBUTION LINES  IN  PERMAFROST AREAS

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                                  14-37
          For the design and construction of  the  conduits,  the
considerations for  frost are the  same as for  directly  buried  piping.
Heaving as a result of  freezing and  instability due  to thaw must  be
avoided.  Inside the conduit, water  from leaks or infiltration  must be
able to drain freely to sumps with pumps at low points of  the route.   The
conduits also should have vent pipes extending above-ground at  intervals
of not more than 50 m for venting and drying  with suction  blowers or
compressed air.  In areas with severe or bad  water conditions in  the
ground, drain tiles should  be placed under the conduit leading  to a dry
well or sump with pump at low points of the route.
          The conduit does  not need  to be heated  but its cover  should  be
insulated to prevent condensation followed by dripping on  the pipe
insulation.  When sewer lines or  uninsulated  oold water lines are placed
in the same conduit, its walls should be insulated and heating  can be
provided by reducing or eliminating  the insulation on  the  return  pipe  of
the heat transmission line  so that the temperature in  the  conduit remains
above freezing.  For conduits above-ground the heating requirements can
be calculated from  the heat transmission factors  ("U"  values) of  the
conduit walls and the anticipated ambient air temperatures.  For  buried
conduits, the heating requirements can be determined from  information
given by Gundersen  [5],
14.3.2.4  Reliability, maintenance, security.  The distribution network
is the most expensive and vulnerable part of  the  utility system.   The
consequences of failure are more  severe in cold elimates than under
temperate conditions.  The  reliability of a distribution network  can be
increased by interconnecting adjacent service areas, and by forming a
ring of trunk lines so that a pipe failure or shutdown  can  be isolated
and loss of service can be  avoided as much as possible.  The maintenance
of lines is easiest in large walk-through utilidors but these are only
feasible for trunk lines, particularly where  several utilities  use the
same utilidor.  Buried duets are less maintainable than elevated  ducts  or
box utilidors but their security is greater.  The  duct with its top cover
at ground level is a good compromise for these diverging characteristics.

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                                  14-38
14.3.2.5  Corrosion and grounding.  Insulated  buried  pipes  are  isolated
from the ground by dry insulation so  that corrosion on  the  outside  of  the
pipe is seldom a problem.  When the outer pipe or  the conduit is  of
metal, corrosion must be considered in cold  regions as  elsewhere.   A
special problem arises in permafrost  where grounding  is complicated by the
presence of ice.  The conduit may be  coated  and a  parallel  grounding wire
may be installed (e.g., zinc wire).
          Internal corrosion of the pipes is controlled by  the  addition
of rust inhibitors to the closed circulating water systems.  Steam
distribution systems have a characteristic corrosion  problem in the
condensate return pipes because air enters the system and supports  the
oxidation of steel pipes.  One solution is to  use  (fiber reinforced)
plastic pipes for condensate return lines.
14.3.6  New product developments.  There is  a  need for  materials  and
products to make the installation of  individual service lines more
economical because they are the relatively most expensive part  of the
whole network.  Pre-insulated piping  in lengths up to 25 m  is becoming
available for this purpose, including pre-insulated T-pieces and  bends.
The tube is copper or steel, the insulation  is plastic  foam or  glass
wool, and the continuous outer jacket is HD  polyethylene.   The  solder  or
braze joints are covered with insulation shells and a heat  shrink sleeve
for tightness.  Installation is by direct burial in a simple trench.
          Another development uses a  flexible, corrugated tube, plastic
foam insulation, flexible, corrugated outer  tube and  extruded plastic
jacket.  This "cable-pipe" is produced in long continuous lengths and
supplied on large reels.  Installation is extremely fast; the pipe  can
also be pulled through conduits (currently available  in Europe).
          A plastic insulating culvert that  is becoming popular is  used
as a loose fitting sleeve over bare steel pipes.   Standard  2 m  long
lengths are slipped over the pipes and joined with heat shrink
sleeves.
14.3.3    Gas distribution
          Design and construction of  gas distribution systems in  arctic
and subarctic regions (regions underlain with  permafrost) must  deal with

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                                 14-39
special problems not encountered  in other areas.  The  basic  engineering
principles governing design of gas distribution  systems  in  temperate
climates also apply in cold regions.  The special problems  encountered
are discussed in the following paragraphs.
14.3.3.1  Scope.  The gas distribution system  consists of the  piping,
supports, valves, meters, and all such necessary appurtenances from the
gas transmission line (or other primary source)  to  the gas  piping  at the
buildings.
14.3.3.2  Locations.  The gas piping may be buried,  installed  at ground
level, or may be an overhead distribution system, depending  upon the site
conditions and the overall concept and usage of  the  installation.   The  type
or types of soil at the site, depth and structure of the permafrost, water
content, surface drainage, etc., must be known.  The method  to be  used  to
preserve site stability is determined by other disciplines.  The type of gas
distribution system to be designed must be consistent  with  the overall
concept.  For example, if a thick insulating gravel  pad  is  to  be provided
for the construction site, a direct burial system may  well  be  selected.
14.3.3.3  Direct buried systems.  Where soil types  and the  natural
drainage patterns permit, the direct buried gas  distribution system is most
desirable from standpoints of economics, security,  and area  utilization.
The soils must be non frost-susceptible, and seasonal  moisture must readily
drain from the area.  Where soils consist of frost-susceptible mateials, and
where surface water stands without draining away, the  gas piping should not
be direct buried.  Metal and plastic piping is used  for  gas  distribution
systems.  If piping is installed  in soil which is frost-susceptible or water
saturated, the water can freeze to the pipe, forming ice anchors.   A section
of piping secured between two ice anchors can  fail  (usually  at the
connecting points) due to axial stress from further  temperature reduction.
          Where direct buried gas piping must cross  road and traffic
lanes, the piping should be installed in a protective  sleeve or culvert.
The piping within the sleeve should be provided with supports  or spiders
which will position the gas pipe concentric with the sleeve.  Where the
ends of the sleeves are buried, the ends should  be  sealed tightly  to the

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                                 14-40
gas pipe with flexible boots and drawbands or clamping devices.   Several
types of these boots are available.  Where the ends of the  sleeves  extend
to daylight due to area grading or to road elevation, the ends may  be
left open.  The sleeve or culvert should be pitched slightly  to  ensure
proper drainage of moisture.
          The design and installation of the gas distribution system must
include provision for the expansion and contraction of the  piping caused
by changes in temperatures of the soil and/or the gas.  Where the system
supply is obtained from an above-ground transmission line,  the product
temperature may range from 27C to -50C.  The range of ground temperature,
of course, is less.  It also changes more slowly.  Flexibility may  be
worked into the system layout, making use of ell-shaped and zee-shaped  runs,
with properly located anchors.  On long straight runs, expansion loops  must
be provided.  Legs of the loops should be encased in suitable resilient
material to allow space for pipe movement when required.  It  is  recommend
that the loops be pre-stressed when installed, and adjusted so that the
loop will be in the neutral position at minimum design temperature.
          Drip pockets for moisture or gas condensate accumulations with
blow-off pipes and valves are required at all low points  in the  system
and at the base of risers.  Natural gas in cold regions may have a
sufficient water or moisture content to require dehydrating.  This, of
course, is done at the well heads or at a collecting point  in the gas
fields.  Dehydration is accomplished with diethelyne glycol,  triethelyne
glycol, or alcohol process.  In each process, there is a  carry-over which
collects at the system low points and must be removed periodically.  For
buried piping systems, a small diameter (13 mm) return bend from the  drip
leg, with a pipe extension to above-ground level, and terminated with a
blow-off valve will serve to remove accumulated liquids at  the drip
collection points.  The blow-off pipe should extend well  above  the
expected snow level, and should be protected from physical  damage by a
guard post.
14.3.3.4  Ground level systems.  A gas distribution system  installed
just high enough above the ground  to be exposed to  the normal snow  level
is called a ground level system.   It is the most simple and economical

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                                  14-41
system, but is vulnerable  to  damage  and  its  use must be carefully
considered.   In general, the  concept can only be employed in areas
requiring a limited  number of service connections and where the piping
can be routed to  avoid  the planned  traffic  patterns.
          Holes for  support posts  should be  made with a drill or soil
auger.  The diameter of  the hole  should  be  approximately 8 cm larger than
the diameter  of the  greater axis  of  the  support member.  Depth of the
hole should extend sufficiently into the permafrost to ensure sufficient
anchor, when  re-frozen,  to resist  the lifting force of seasonal thawing
and freezing.  The required depth  will depend upon the climate, the soils
and the permafrost conditions at  the particular site, and should be
determined by soil experts assigned  to the  project.  As a rule, the
required depth of penetration into  the permafrost will be approximately
two-and-a-half times the depth of  seasonal  thaw.  The void space around
the support member in the  hole should be filled with a slurry prepared
from suitable water  and  fine  soil.   The  water should be free of minerals
and acid so that  the freeze point  will not be depressed.  The soil should
be a fine sandy type.   The slurry  should be  poured or ladled into the
hole up to grade  level  and allowed  to freeze in place.  Freezing time in
the permafrost strata will vary somewhat with the temperature of the
permafrost and with  the  ambient temperature, but generally should be
between two and seven days.
          Supports must  be spaced  at intervals which will prevent
excessive sag and stress in the piping.   The load on the pipe consists of
the weight of the pipe,  the ice and  frost build-up (up to 5 em thick),
and the wind  loads.
          Tops of the support posts  should be trimmed as required to
provide proper grading  of  the gas  piping.  The piping should be supported
on or by the  posts in a  manner to  restrain longitudinal movement but
permit free axial movement caused  by expansion and contraction of pipe.
On wooden posts, a two-piece  clamp,  similar  to an offset pipe clamp
serves very well.  Legs  of the clamp may be  secured to the post with
thru-bolts or lag screws.   On steel  posts, a wall bracket hanger may be

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                                  14-42
bolted or welded in place and the pipe supported  from  elevis-type  hangers
and hanger rods.  Hanger rods should be as short  as  possible  to minimize
pipe sway due to wind pressure.
         Expansion loops must be supported in a manner  to  preclude
additional stress on the piping and permit proper  function of the  loop.
The loops should be designed and installed in such manner  that the loop
stresses occur at maximum design temperature and  will move toward  the
un-stressed or neutral position as the pipe temperature decreases.
Expansion loops are usually considered to be on a horizontal  plane.
Where it is to the advantage of the system design or layout,  vertical
loops may be best.  Vertical loops should be sized at  least as required
for allowable stress in the piping, and may be oversized if the loop is
to be used for a pedestrian or vehicle passageway.  Drip pockets and
blow-off valves should be provided at the base of the vertical legs of
the loop. Supports for the vertical loops must be designed for ioe and
wind loads as well as for piping loads.
          Anchors, for controlling pipe expansion, must be properly
located at the time of design.  Where possible, the  anchors and loops
should be uniformly spaced to minimize unbalanced thrusts  on  the anchors.
Commercial type anchor elamps may be adapted to the  support posts,
whether of wood or of steel, or field-fabrieated  anchors may  be designed.
          Slip-type expansion joints or couplings are not  recommended  for
use in gas distribution systems in cold regions.   At extremely low
temperatures, the seals of the joints harden and  lose  the  elasticity
required for the sealing effect.  The use of slip joints or couplings  can
be avoided by proper use of bends, loops or offsets, eliminating an
unnecessary risk of system failure.
14.3.3.5  Overhead Distribution Systems.  An overhead  system, as
diseussed herein, is a system in which the gas piping  is installed a
minimum of 2 m above the finished grade of maximum snow line.  The
purpose of such a system would be to permit free  use of all the area for
pedestrian or low vehicle (snowmobile) traffic.   Higher clearances may be
provided across streets and roads for passenger cars and trucks.   An
overhead system is most expensive.  It is also the most vulnerable to
damage from traffic and from storms.

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                                     14-43
          Support for the overhead system are designed and installed as

described for ground-level systems, with due consideration given to wind

and ice loads.  Where long pipe spans are required,  such as at road and

street crossings, a cross-beam must be provided from which the pipe can

be suspended.  The beam may be of open-web bar joist design, or wood beam

suitable for the span.  Traffic signal arches of tubular construction

should also be considered.

14.4      References
1.   U.S. Army CRREL/Alaska District, "Electircal Groundings of Power and
     Communications Facilities for Tactical Operations in Arctic Regions".
     Hanover, New Hampshire, February 1973.

2.   Special Alloy Steel for Extreme Low Ambient Conditions.  British
     Petroleum and Westinghouse Street Corp.

3.   Stockbridge, G. VI. "Overcoming Vibration in Transmission Cables".
     Electrical WorkL  (Dec. 26, 1925) Vol. 86, No.  26.

4.   Alaska District Corps of Engineers and Alaska Electirc Light and Power
     Company experience with 'Taku' winds- in the Juneau,  Alaska area.

5.   Gundersen, D., "Frost Protection of Buried Water and Sewer Pipes",
     Draft translation TL666, U.S. Army Cold Regions  Research and
     Engineering Laboratory, Hanover, New Hampshire,  1978.

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                               SECTION  15
                         THERMAL CONSIDERATIONS
                                 Index
15        THERMAL CONSIDERATIONS                                      15-1
15.1      Introduction                                                15-1
15.1.1    Site considerations                                         15-1
15.1.2    Design considerations                                       15-2
15.2      Freezing of Pipes                                           15-2
15.2.1    Freeze-protection                                           15-4
15.2.2    Thawing of frozen pipes                                     15-6
15.3      Heat Loss from Pipes                                        15-7
15.3.1    Pipe environment                                            15-8
15.3.2    Physical methods of reducing heat loss                      15-12
15.4      Heat Loss Replacement                                       15-15
15.4.1    Fluid replacement                                           15-15
15.4.2    Point sources of heat                                       15-15
15.4.3    Pipe heat tracing                                           15-17
15.4.4    Electric heat tracing                                       15-18
15.4.5    Friction                                                    15-21
15.5      Utility Systems                                             15-21
15.5.1    Thermal analysis                                            15-22
15.5.2    Operation                                                   15-22
15.6      Foundations for Pipelines                                   15-23
15.6.1    Buried utilities in permafrost areas                        15-23
15.6.2    Frost effects                                               15-27
15.6.3    Above-ground pipes                                          15-28
15.7      Materials                                                   15-28
15.7.1    Piping materials                                            15-28
15.7.2    Insulation                                                  15-30
15.7.3    Soils                                                       15-32
15.8      Buildings and Structures                                    15-36
15.8.1    Thermal design                                              15-36
15.8.2    Foundations                                                 15-36

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                             Index (Cont'd)
                                                                     Page
15.9      Thermal Calculations                                       15-38
15.9.1    Steady-state pipeline solutions                            15-39
15.9.2    Subsurface temperatures                                    15-49
15.10     Example Problems                                           15-58
15.11     References                                                 15-72

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                           List of Figures
Figure                                                               Page
15-1      The Freezing of Water Pipes                                15-3
15-2      Frost Penetration and Heat Loss from Bare and Insulated
          Pipes Within Seasonal Frost                                15-10
15-3      Methods of Insulating Buried Pipes                         15-11
15-4      Relative Heat Loss from Single Pipes Insulated with
          same Volume of Insulation                                  15-14
15-5      Relative Heat Loss from Two Pipes Insulated with same
          Volume of Insulation                                       15-14
15-6      Thawing and Settlement of Buried Pipe Test Loop in
          Ice-rich Permafrost, Bethel, Alaska                        15-25
15-7      Effect of Insulation Thickness on Thaw Perturbation        15-25
15-8      Effect of Depth-of-Bury on Thaw Perturbation               15-26
15-9      Unfrozen Moisture Content in Soils                         15-33
15-10     Steady-State Thermal Equations for Above-Surface Pipes     15-42
15-11     Steady-State Thermal Equations for Below-Surface Pipes     15-43
15-12     Steady-State Thermal Resistance of Various Shapes
          and Bodies                                                 15-44
15-13     Temperature Change and Freeze-up Time in Pipes             15-45
15-14     Thermal Resistance of a Hollow Cylinder                    15-46
15-15     Thermal Resistance of a Soil Mass Covering a Pipe          15-47
15-16     Dimensions of a Thaw Cylinder Around a Pipe Buried
          in Permafrost                                              15-48
15-17     Ground Temperatures Around Buried Water Pipe,
          Yellowknife, N.W.T.                                        15-50
15-18     Sinusoidal Air and Ground Temperature Fluctuations         15-51
15-19     Ground Temperatures and Thawing Around Buried Pipes
          Pipes in Permafrost                                        15-52
15-20     Correction Coefficient                                     15-55

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                            List of Tables
Table                                                                Page
15-1      Comparison of Insulation Properties of Various
          Materials                                                  15-32
15-2      List of Symbols                                            15-40
15-3      Thermal Conductivity of Common Materials                   15-41
15-4      Some Examples of n-Factors                                 15-57
15-5      Some Examples of m-Factors for Ice Thickness               15-58
15-6      Conversion Factors to SI Units                             15-59

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                                  15-1
15        THERMAL CONSIDERATIONS
15.1      Introduction
          Cold regions utility  systems must  function  under  severe
climatic conditions.  Since  thermal  considerations  are  as  important,  or
more important than,  the hydraulic and structural  features,  they must be
included in the selection  and design of materials,  components,  and
processes [1,2,3].  Thermal  analyses are  necessary  to design for freeze-
protection, foundation stability, thermal  stress and  economy.   In this
section the major emphasis is on  the thermal  design of  piped water  and
sewer systems.  Thermal aspects are  discussed,  and  simple  equations and
illustrative examples are  presented  solving  some of the thermal problems
encountered in utility system design.  Cold  regions building design and
foundation considerations  are only briefly considered;  other references
must be consulted for detailed  design information  on  these  subjects.
15.1.1    Site considerations
          Climatic and geotechnical  site  information  is necessary for
thermal analysis and  design.  Adequate air temperature  data, which
include the range, mean and  various  indices,  are usually available  from
nearby weather stations or from published  charts and  reports [4,5,6], but
the local micro-climate will modify  these  values (see Appendix  H).   Local
ground temperatures are often not available,  and extrapolations are
inadvisable since they can vary significantly with  the  air  temperature,
snow cover, vegetation, drainage, topography, and  soil  properties.   The
most reliable approach is  to obtain  long  term actual  site  measurements.
Limited data must be modified to  estimate  the extreme climatic  conditions,
or to make allowances for  surface changes  resulting from construction and
development.
          Geotechnical conditions are frequently highly variable within a
small area and site-specific surveys consistent with  the thermal and
structural design considerations  are imperative.   Of  primary concern  is
movement and possible failure due to the  freezing  and thawing  of the
surface.  Therefore,  the maximum  thickness of the  active layer  and  the
soil thermal properties and  frost-susceptibility must be determined.   In

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                                  15-2
permafrost areas, particularly  in  high  ice  content  soil,  the  soil survey
must extend to the maximum  range of  anticipated  major thermal  effects,
and surface conditions  and  drainage  patterns  must be noted.
15.1.2    Design considerations
          The primary areas of  concern  in  the design of utilities in cold
regions are failure of  pipes due to  freezing  of  water,  thaw-settlement or
heaving of foundation soil,  thermal  strain  and associated stress, and
economical operation.
          Utility systems in cold  regions  are thermally designed with a
conservative  safety factor, and often  the  worst  conditions that could
occur simultaneously are considered.  This  is justified by:
          a)  simplifications and  assumptions within the  thermal
              equations and models;
          b)  limited data  and  random  nature  of  the climatic  and physical
              site conditions;  and
          c)  variations and assumptions in the  physical  and  thermal
              properties of materials  such as insulation, soils and pipes,
Although  the  thermal characteristics may be precisely defined, the
application and  control is  complicated.  In practice, it  is  often the
unexpected or unforeseen conditions  that result  in  damage or failure.
Thermal design must consider more  than  the  precise  thermal analysis.
Experience and  judgement are also  essential.
15.2      Freezing of Pipes
          Freeze damage to  containers  of fluid,  including pipes, occurs
due to  the expansion of water changing to ice [7].   This imposes a
pressure  on the  still unfrozen  liquid  that can reach hundreds of
atmospheres.  Failure  is caused by hydrostatic pressure,  not by  the ice
expanding directly on  the  walls [8],  The freezing  of quiescent  water in
pipes occurs  in  stages  as  illustrated  in Figure  15-1(a)  [9],   Water must
always  supercool,  typically -3 to -7C in quiescent pipes with  slow
cooling,  before  nucleation  and  freezing produces dendritic ice growth.
Further cooling  results in  the  growth  of an annulus of ice inwards  from
the pipe  walls.

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                                   15-3
    PIPE CROSS SECTION
    FREEZING STAGES
        .  .x. ,    Dendritic
        Initial     | jCe  |
      co (-down  growth
    Annular ice growth
  Final
cool-down
    i            ii     i r
    TEMPERATURES
   0

  -4
                 Water temperature
                 Pipe wall temperature
Nucleation temperature
                           Time
 (a) The  stages in the freezing of a quiescent water pipe [9J.
                                Water
(b) Ice bands formed during  the freezing of flowing  pipe [10].

 FIGURE  15-1.   THE FREEZING OF WATER  PIPES
          Dendritic ice formation increases  the start-up pressure
required  to  reinstate flow, particularly  in  small-diameter pipes and  slow
fluid  cooling  rate, and can effectively block the pipe in much less time
than that required for the pipe to become blocked by annular growth of
ice [9].
          The  freezing process for fluid  flowing in pipes is not simply
by annular growth  and such an oversimplification can lead to false
conclusions  and  errors in design.  Gilpin [10]  observed  that for flowing
pipes  ice does  not grow as a uniform  thickness  along the pipe but occurs

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                                  15-4
as cyclical ice bands  of  a  tapered  flow passage (Figure 15-1(b)).
Further cooling will freeze  off  the  narrow neck,  arresting flow, and
subsequent freezing can result  in  pipe  breaks between each ice band.  No
ice formation  in  pipes can  be  safely tolerated and fluid temperatures
should not be  allowed  to  drop  below 0.5C.
          As soon as the  water  temperature drops  to freezing,  ice
formation may  start somewhere  in the system,  usually on metal  valves and
fittings.  Ice plugs formed  in  this  manner can prevent start-up or
draining of the pipes  long  before  the entire  system freezes.  The
recommended design freeze-up time  is only the time available before water
in an inoperative system  reaches the freezing point.  This time period
must be sufficient to  permit repairs or to drain  the system, and depends
upon the availability  of  maintenance personnel and equipment.
Understandably, the design  freeze-up time may have to be several days in
small communities, while  in  larger  centres the time may, with  caution, be
reduced to less than one  day.   The  shortest freeze-up time and the
largest number of freeze-ups are associated with  small-diameter service
lines.  The maximum safety  factor  freeze-up time  is the time necessary
for the fluid  to  drop  to  -3C,  the  nucleation temperature.  No portion of
the latent heat for complete pipe  freezing should be included  in freeze-
up calculations.  (See  Figure 15-13,  Example 15.9).
          Gravity pipelines  or  open channels  may  also freeze by icing up.
The initial filling of water or sewer pipelines is often a critical
period with respect to freezing in  this manner.  Additionally, frosting
and icing may  occur in the  crown of uninsulated sewer lines when the heat
input is low;  however, this  may melt out when the flow is increased.
15.2.1    Freeze-protection
          The  design freeze-up  time can be increased by higher operating
temperatures,  increased insulation,  and locating  pipes where ambient
temperatures are  warmer.  Excess temperature  increases heat loss,
introduces inefficiency,  and is expensive.  Utility systems that are
highly insulated  are preferable, since they require less heating and
provide a longer  freeze-up  period.   A similar argument applies to buried
systems as compared to exposed  pipes.  Insulation only retards freezing,

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                                  15-5
and whenever  ambient temperatures are below freezing, heat loss from
pipelines must  be  replaced.   With respect to freeze-protection,
insulation  can  be  less  important than the addition of warmer water and
the maintenance of flow.
          Small-diameter  pipes,  such as service connections, have less
specific and  latent heat  available and the design freeze-up time is
usually only  a  matter  of  minutes or a few hours.  They are particularly
vulnerable  to any  interruptions  in flow,  and freezing usually occurs in
them  first.   Thawing capability  is therefore mandatory for small-diameter
pipes.
          Buried insulated  piping will not usually significantly affect
the ground  temperatures,  but  bare or high-temperature pipes will have a
warmed and  thawed  zone  around them.  This should not be relied upon to
increase the  freeze-up  time,  since soil texture and moisture content vary
significantly,  and the  freezing  temperature of moisture in soils is often
below 0C,  particularly in  cohesive soils [11],  Therefore, the
deliberate  thawing of ground  is  not recommended.
          Water intakes and  sewer outfalls which have intermittent or low
flows and wells that have static water levels within the freezing zone
may require freeze-protection.   This can  be accomplished with insulation
and heat tracing or circulating  raw unheated water (see Figure 3-8).
Alternatively,  air pressure  has  been used to lower the static water level
in small-diameter  pipes to  below the ice  or frost level when not in use
[12].
          Since fire protection  may be a  major function of piped water
systems, freeze-protection  of fire hydrants is imperative.  Conventional
hydrants on buried  piping within frozen ground may not drain; therefore,
they must be  pumped  out after use and  can be filled with a non-toxic
anti-freeze mixture  such  as  propelene  glycol.   In-line hydrants (see
Figures 6-22, 6-23 and  8-5) or hydrants located within manholes (see
Figure 6-24)  are preferred  since the water within the pipe to conven-
tional offset hydrants  will be static  and must  be freeze-protected.
          Where the  demand  is very low or intermittent,  it may be more
economical to fill  and  operate a pipeline as required and  drain it

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                                  15-6
between uses, than to incorporate measures  to  prevent  the  freezing of its
contents.  Such systems  usually  require  pre-heating  and  post-heating of
the pipeline during an operating  cycle.   This  principal  is the basis of a
long water supply line to  a  small arctic  community [13],  and a proposed
water distribution system  to buildings equipped  with water storage tanks
[14],  For both of these situations,  uninsulated surface  pipelines have
been utilized during  the summer,  then drained  and not  operated during the
winter.  Storage and  intermittent discharge has  also been  used to prevent
the icing-up of low flow or  long  sewer lines or  outfalls  [15].
          Independent back-up  systems should be  provided  for critical
components, such as circulation  pumps.   Systems  with heating cables
should prevent freezing  even if  flow ceases, provided  of  course that
electricity to operate these is  available.   In cold  regions, all utility
system components must be  capable of being  conveniently and quickly
drained.  If freezing is imminent,  pipelines should  be manually flushed
or drained through hydrants  or special  fittings  judiciously located at
low points in the  system [16],  Wherever practical,  water and pressure
sewer  systems should  be  sloped to central draining facilities. Compressed
air [12,17] or "pigs"  [18] may be used  to force  the  fluid from small-
diameter lines.
          Some flexible  pipe materials,  such as  polyethylene and  small-
diameter copper  lines, may not rupture  upon freezing but the expansion
depends  upon  the manner  of freezing and, at present, no pipe  should be
relied upon  to provide  service after freeze-thaw cycles.  Various methods
to  prevent or limit  the  freeze damage of pipelines have been  proposed
[7],   These  provide  additional thermal  resistance at convenient,  pre-
determined  locations  where the hydrostatic  pressure that occurs with
freezing can  be  dealt with by a pressure relief valve, bursting
diaphragm,  expandable section, or other  device, or  else that  short
section  of  pipe  can  be  sacrified.
 15.2.2   Thawing  of frozen pipes
          It  is  prudent  and  often mandatory to  provide for  the  thawing  of
all  water  and  sewer  pipes  and wells  that may  freeze.  Remote  electrical
 thawing  methods  which must be incorporated  into  the briginal  design

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                                  15-7
Include skin effect,  impedence,  and  various resistance wire and commer-
cial heating cable  systems.   Frozen  wells have been thawed by applying a
low voltage from a  transformer  to  a  copper wire located inside the drop
pipe [19],  Once a  small  annulus  is  melted, the flow can be reinstated
and it will thaw the  remaining  ice in the pipe.  A common approach to
thawing frozen  small-diameter metal  pipes is to pass an electrical
current from a  welder  or  transformer through the pipe [20],  This
operation is greatly  facilitated  if  readily accessible thaw wire
connections are provided.  A frozen  pipe can also be thawed by passing
warm water through  a  small-diameter  pipe which is installed on the
exterior surface of the pipe.  This  thaw tube system can also be used as
a carrier pipe  for  electric  heat  tracing, a return line for
recirculation,  or a bypass of the  main line.  The capital cost of this
system is much  lower  than electric heat tracing but it requires manual
operation.  Utilidors  that incorporate pipe heat tracing can be thawed,
provided that these heating  lines  use an antifreeze solution or they were
drained prior to freeze-up.   Exposed pipes may also be thawed with warm
air.  Injection thawing with steam or hot water can be used to thaw water
and sewer lines if  adequate  access and room for hoses, equipment and
personnel is provided  at  manholes.  Small-diameter water lines of any
material can also be  quickly thawed  by pumping warm water into a
smaller-diameter plastic  hose that is inserted into the frozen pipe [21].
These thawing methods  are detailed in Appendix F.
          The energy  required to  thaw a frozen pipe is largely the heat
necessary to melt the  ice.   Knowing  the heat that must be supplied and
the energy output of  a thawing  system, the time to melt the ice can be
calculated.  In practice, an opening that permits a flow to commence may
be all that is  necessary  to  thaw the remaining ice, provided that the
flushing water  is warm.   Long lengths may be thawed this way in stages.
In many cases,  heat tracing  systems  are sized to thaw or reopen the line
in a reasonable length of time  and not just to supply the heat loss
necessary to prevent  freezing.
15.3      Heat  Loss From  Pipes
          The thermal  design must  prevent the freezing of water and
wastewater within pipes or tanks  that are exposed to below-freezing

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                                  15-8
temperatures, and provide  for  economical  operation.   The primary and
complementary methods are  by reducing  and replacing  heat losses.  Heat
loss is proportional to  the difference between the  fluid and the ambient
temperatures, and the thermal  resistance  of  the intervening materials.
Measures that provide a  more favourable environment, such as buried
pipes, and measures that increase  the  thermal  resistance, such as
insulation, will reduce  the rate of  heat  loss.  These methods do not
eliminate freezing, rather they  retard it;  therefore, heat losses must be
replaced by removing the cooled  water  before it freezes, or by heating
the fluid or the pipe surface.
          Estimates of  the maximum rate of  heat loss are required to
determine the freeze-up  time and to  design  heaters,  circulation pumps and
heat tracing systems.  Annual  heat loss estimates are necessary to
determine total energy  requirements  and assess methods of reducing
these.  Solutions to these thermal problems  are outlined in Section 15.9.
15.3.1    Pipe environment
          The freeze-up  time and the total  heat loss are dependent upon
the temperatures encountered in  the  pipe  environment.  Above-ground
piping systems must be  thermally designed for  the lowest expected air
temperatures, perhaps -40C to -60C.   For  reliable and economical
operation during the winter, exposed piping  must be completely insulated
and usually a flow must  be maintained. Some heating of water is
necessary.
          Extreme air temperatures are significantly moderated by the
ground surface conditions, primarily snow cover and vegetation, and the
thermal properties of the  soil.  Of  importance to heat loss and the
design of buried pipes  are the minimum ground  temperatures and the
maximum depth of freezing  or  thawing.   Surface temperature variations are
attenuated with depth,  depending upon  the thermal diffusivity (thermal
inertia) and latent heat (moisture content)  of the soil.  While air
temperatures may have an annual  range  of  90C, the temperature at a depth
of 2 m may vary from 2C in saturated  organic  soils in undisturbed areas,
to as much as 25C in exposed  dry  soils or rock.  At a depth of 10 m,
seasonal temperature fluctuations  are  usually negligible.  Daily air

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                                  15-9
temperature  fluctuations  are  negligible below aproximately 0.5 to 1.0 m
of bare soil or  ice  or  0.5 m  of  undisturbed snow.   Air temperature
fluctuations are moderated with  depth and their influence is Telt some
time later.  The lag time depends  upon the surface conditions and soil
thermal properties,  and at a  depth of 2 m may be one to five months.
Therefore, minimum ground temperatures and maximum frost penetration may
occur when the extreme  winter temperatures have long passed.  Frost
penetration  will be  greatest  in  rock or bare, dry soils.  Undisturbed
snow cover itself may reduce  the depth of frost by an amount equal to its
own thickness [22],   Locating utility lines away from travelled, plowed
areas, such  as at the back of lots rather than under roadways, may
significantly reduce heat loss and increase the freeze-up time, but years
with little  snowfall, snowdrifting and man-induced changes must be
considered.
          Conventional  municipal piping can be installed below the
maximum depth of seasonal frost.   In cold regions, the frost penetration
is often greater than the common pipe depths of 2  to 3 m, and may be 6 m
or more in exposed dry  soil or rock.  Deep frost penetration, high
groundwater, hilly terrain, rock or other factors  may make it more
practical and economical  to install all or portions of the utility system
within the frost zone [23,24,25].   In these cases, the degree of freeze-
protection necessary will depend upon the ground temperatures at the pipe
depth.  Where pipes  are only  intermittently or periodically within frost,
conventional bare pipes may be adequate,  provided  a minimum flow can be
maintained by circulation, bleeding or consumption.  Frost-proof
appurtenances, stable backfill and some heating may also be necessary.
Even in these marginal  cases,  insulating  pipes in  shallow or low
temperature  areas will  greatly increase the reliability of the system and
is highly desirable.  Heat loss and freeze danger  are significantly
reduced by insulating the pipes.   This is illustrated in Figure 15-2.
          Insulated  pipes can be installed in shallow trenches or within
berms at the ground  surface.   In these cases, there is often little
thermal advantage in deep bury, but the minimum desirable cover should be
such that daily  temperature fluctuations  are not "felt".   This is 0.5 to

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                                  15-10
       Nov D J  F M A M  J J  A S O N Dec
Ground
                Pipe insulated with
                50mm polyurethane
  FIGURE 15-2.  FROST  PENETRATION  AND HEAT LOSS FROM BARE AND INSULATED
                PIPES  WITHIN  SEASONAL FROST [27]
1.0 m for exposed surfaces.   The minimum depth of cover is also governed
by the ability of the  insulation and  pipe to withstand anticipated
traffic loads, and  this  depth is usually approximately 1 m.  Other
factors which will  influence  the average and local depth of bury are  the
pipe grade and terrain;  frost heaving problems, which are greater for
shallow pipes; and  access  for maintenance.  In some cases, it may be
possible to balance  the  reduction  in  excavation cost with the cost of
insulation and other  freeze-protection measures necessary for shallow
buried pipes within  the  seasonal frost zone [23,24,25].
          Buried pipes within seasonal frost can be pre-insulated,
usually with polyurethane,  or a layer of insulating board, usually
polystyrene, can be  placed  above  the  pipe (Figure 15-3).  The latter
method uses bare pipes and  fittings and the board insulation is often
less expensive; however, the  installation cost will be higher and the
effectiveness of the  insulation is lower than direct insulation of the

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                     15-U

                               placed 
              o
                  ot
inched.

ejec
                ted
-



                                poW
                                                          of   
                                                                         <)t
                                .ty,.          or 1-0 .

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                                  15-12
          Buried pipes at any depth  in  permafrost  areas  must  be protected
from freezing, and pipes and appurtenances must  be insulated.   Deeper
pipes will experience less extreme ambient temperatures, lower maximum
rates of heat loss and longer freeze-up  times.   However, the  heating
period will be longer and pipes  installed  below  the  seasonally thawing
active layer may require freeze-protection and heating  all  year.  The
total annual heat loss is relatively constant with depth.   The most
important function of soil above  buried  insulated  pipes  is  in reducing
the ground temperature amplitude  by  its  thermal  inertia  and latent heat.
The thermal resistance of the soil is often  insignificant  (see Example
15.3).  Depth-of-bury considerations in  permafrost areas are  similar to
those for pipes within seasonal  frost,  with  the  possible additional
problems associated with the thawing of  ice-rich permafrost.
15.3.2    Physical methods of reducing  heat  loss
          The primary physical method of reducing  heat  loss is
insulation.  It is impractical  to prevent  ground moisture,  humidity or
water from pipe failures from reaching  the insulation and,  since moisture
content is a key factor  in determining  the thermal performance of
insulations, only near-hydrophobic insulations  should be used.  Even
these insulations will usually  require  some  physical and moisture
protection.
          Systems that are liberally insulated  are generally preferred
since they require minimum heating and  circulation,  provide a longer
freeze-up period, and have less  influence  on the ground thermal regime.
An economic analysis to  balance  heating and  insulating  costs  should be
performed to determine the minimum amount  of insulation that  is required
(see Example 15.11).  Other  factors, such  as the freeze-up time, the
maximum rate of heat loss and practical dimensional considerations, must
also be considered in the selection  of  insulation  thickness.
          Heat loss estimates for piped systems  must adequately allow for
poorly insulated or exposed  sections of pipes,  joints and appurtenances,
and thermal breaks such  as at pipe anchors.   A 150-mm gate valve has a
surface area equivalent  to 1 m  of bare  pipe.  If this valve were left
exposed it would lose as much heat as about  60 m of 150-mm pipe insulated

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                                  15-13
with 50 mm  of  polyurethane  insulation and freezing will occur at the
valve first.   Therefore,  the  thermal  resistance around appurtenances
should be 1.5  times  that  required around connecting pipe lengths.  This
illustrates  the danger  of restricting thermal analysis and design to
straight sections  of  piping  and  the  importance of fully insulating the
piping system.
          Heat loss  and the  volume of materials can be reduced by
minimizing  the perimeter  and  exposed  surface area.  This is most
important for  above-ground  pipes  and  facilities.  Insulation is most
effective when it  is  placed  directly  around the source of heat.  These
characteristics are  illustrated  by simple shapes in Figures 15-4 and
15-5.  Where there is an  air  space,  the thermal resistance of the pipe
air film can be quite significant and must be considered.  For a single
pipe, insulation  is  best  applied  in  an annulus directly around the pipe.
Heat loss from pipes  in a utilidor is less than that of separate pipes
insulated with the same total  volume  of insulation, if the utilidor is
compact.  This is  often not  possible.  The spacing requirements for
pipes, appurtenances, installation and maintenance, particularly for
central heating lines,  often make it  necessary to design utilidors with
large air spaces  and  these  utilidors  will be thermally less efficient
than separately insulated pipes.   Heat supplied from warm sewer pipes,-
central heating lines or  heat  tracing may make utilidors thermally
attractive.  Pipes within utilidors may also have a longer freeze-up time
because of  the larger heat  source available compared to separate pipes.
This is particularly  important for small-diameter pipes.  Heat loss can
also be reduced and  freeze-protection improved by installing one water
pipe inside of a  larger one, rather  than using two separate pipes.  This
technique is applicable for  freeze-protection of small-diameter
recirculation  pipes  used  to maintain  a flow in supply lines, or dead ends
within a water distribution  system.
          Heat loss  can also be  reduced by lowering the operating
temperature of water  pipelines,  but  the benefits of this are only
significant where  the ambient  temperatures are just slightly below
freezing.  The heat  loss  from  insulated storage tanks and pipes is

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                             15-14
               1.5 r
With air film    1.0        N/A
  No air film    1.0        1.1
                       1.5 r
                     1.5
                     2.8
                          1.9
                          4.6
FIGURE 15-4,
    1.5r
With air film
  No air film
 RELATIVE  HEAT LOSS  FROM SINGLE PIPES  INSULATED
 WITH  SAME VOLUME OF INSULATION
1.0
1.0
n
Q
V.V
 0.64
 0.78
                                   X
0.78
1.0
                                     2r
0.93
1.25
 With air film       0.93
   No air film      1.25
                        0.50
                        0.50
                            0.80
                            0.80
 FIGURE  15-5.   RELATIVE  HEAT LOSS FROM TWO PIPES  INSULATED
                WITH  SAME VOLUME OF  INSULATION

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                                  15-15
 often  small  compared to the energy requirements to raise the source water
 to  the  system operating temperature.  Therefore, lower operating temp-
 eratures  may significantly reduce energy requirements for preheating
 rather  than  heat  losses within the piping system.  Because of the greater
 relative  reduction  in heating requirements, utility systems in the sub-
 arctic  are'often  operated nearer freezing than those in arctic regions.
 Any reductions in heat loss and preheating requirements must be balanced
 with the  reduction  in freeze-protection when systems are operated nearer
 the freezing point.
 15.4     Heat Loss  Replacement
          Heat loss  cannot be completely prevented.  If ambient tempera-
 tures are below freezing, it is simply a matter of time before freezing
 will occur unless heat is added to the fluid or it is replaced with
 warmer  fluid.   Heat  can be added either continuously or at point sources.
 15.4.1    Fluid replacement
          Freezing will not occur if the liquid residence time in the
 pipeline  is  less  than the time necessary for it to cool to the freezing
 point.  The  quantity and temperature of the replacement water (i.e.,  the
 total heat available)  must be sufficient and the flow must be reliable.
 Operation without additional heating is restricted to situations where
 relatively warm water  supplies, such as groundwater,  are used and/or
where the flow rate  is reliable and  high, such as in some water supply
 pipelines or  trunk mains.   Bleeding  of water has been used to maintain or
enhance the  flow  in  service lines, dead ends and intermittent flowing
pipelines but  the wasting of large quantities of water can be inefficient
and  lead  to  water supply and wastewater treatment problems.   Recircula-
tion will maintain a flow and a uniform temperature within the system,
and  prevent  premature  freezing at  locations with lower than  average
ambient temperatures  or  at  poorly insulated sections.  However,  the  water
temperature will  decline  unless warmer water is added  or the
recirculating water  is  heated.
15.4.2    Point sources  of  heat
          Water may  be  heated  at  the  source,  treatment  plant,  pumping
stations and/or along  the  pipeline or  within distribution  systems  as

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                                  15-16
required.  Heat is commonly  obtained  from fuel  oil fired boilers;
however, simple electric water  heaters  have  been used where the heat
requirements are very  low.   The  heating of water can be a practical use
for low-temperature waste heat,  such  as from electric power generation,
and this should always be investigated  in order to reduce energy costs.
The heating capacity required  to  replace heat losses is based on the
maximum rate of heat loss expected; whereas  annual heat loss energy
requirements are calculated  from the  cumulative heating index (see
Example 15,3). Where the raw water  temperature  is too low and must be
raised to a specified  operating  temperature, the required heating
capacity is determined by the  maximum flow rate, and the annual energy
requirements are determined  by the  total water  demand during the heating
period.
          There must be  sufficient  flow within  the piping system to
distribute the heat which is added.   If the  normal water demand is too
low or is intermittent,  then bleeding or recirculation is necessary.  A
minimum water  temperature can  be maintained  within the piping system by
increasing either  the  flow  rate  or  the  input water temperature while
keeping the other  parameters constant,  or by adjusting them
simultaneously.  High  temperatures  enhance heat loss and introduce
inefficiency.  As  a general  rule, the temperature drop along a pipeline
should always  be kept  to less  than  5C, and  preferably less than 2.5C,
by insulation, higher  flow  rates, or  intermediate heating along the
pipeline or within the system.   However, there is usually little
reduction in heat  loss by limiting  the  temperature drop to less than
0.5C.  By the same analogy, velocities greater than 0.1 m/s for 150-mm
pipes and 0.5  m/s  for  50-mm pipes are of little benefit in reducing total
energy input to maintain a  specified  minimum water temperature.  Higher
velocities, such as for  pitorifice  systems that require a minimum
velocity of 0.75 m/s,  must  be  balanced  with  the electrical energy
requirements for pumping  (see  Example 15.10).
          Sewer lines  are generally warmer than water mains, but freezing
can occur where flows  are  intermittent  or low.   In these cases, a  flush
tank  can be used to periodically discharge wastewater or warm water into

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                                  15-17
the sewer line (see Section  7.2.3.2).   Bleeding water directly into the
sewer lines also adds heat but  this  practice  is usually only recommended
as a temporary measure.  Direct  heating of  wastewater is not
practised.
15.4.3    Pipe heat tracing
          Heating  requirements  to  replace heat  losses and to maintain a
minimum temperature (i.e., prevent freezing)  can be supplied by pipe heat
tracing systems.   Such  systems  are more commonly used in multi-pipe
utilidors but have been  used for single pipes.   Heat is provided by
warming air spaces by convection,  and  in some cases by conduction.  The
pipe heat tracing  system may be  part of a central heating system, or
designed only to heat a  utilidor.   In  the former case, for above-ground
utilidors some of  the high-temperature pipe insulation may have to be
removed (typically 0.25  m every  10 m)  to provide enough heat to prevent
freezing at the lowest ambient  temperatures.   The heat source cannot be
manipulated and when the ambient temperature  increases, inefficient and
undesirable overheating  of the  utilidor and water main occur (see Example
15.5).  Freezing of pipes can result from thermal stratification in large
utilidors or the shielding of small-diameter  heat tracing pipes [30],
          For pipe heat  tracing, low-temperature fluids, generally
between 80C and 98C, are much  simpler to  use  than either steam or
high-temperature water,  and  the  fluid  mixture can be adjusted to depress
the freezing point to the lowest expected ambient temperatures.  The use
of an antifreeze solution protects the heat trace piping, allows start-up
during winter and  provides a means of  thawing frozen pipes.  The
viscosity of low freezing point  glycol and  water mixtures is greater than
that of water; therefore, the required pumping  capacity and friction
losses will be higher.   The  heat transfer characteristics are also poorer
than for water.  For example, a  50%  mixture of  glycol and water would
require a 14% increase in flow  rate  to achieve  the same heat transfer.
Design information on these  heating  systems is  available from the
American Society of Heating,  Refrigeration  and  Air-Conditioning Engineers
(ASHRAE) [31,32].  It should be  remembered  that ethylene glycol is
toxic and cross-contamination must be  prevented.  Alternatively,

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                                  15-18
propylene glycol, which is non-toxic, can  be  used.   These  solutions  are
corrosive to zinc and they can  leak  through  joints  and  pump seals that
will not leak water at the same pressures.  Mechanical  seal pumps should
be utilized.  Some boiler manufacturers  void  their  warranty if glycol
solutions are used.  Special  organic  fluids  can  also be used instead of
water-glycol mixtures.
15.4.4    Electric heat tracing
          Electric heat tracing systems  are  relatively  easily installed
and controlled.  They may be  installed continuously on  water and sewer
pipelines, or only at low ambient  temperature,  freeze-susceptible or
critical locations, such as  road crossings,  service connections or at
appurtenances such as fire hydrants.  Because of the relatively high cost
of electrical energy, these  systems  are  usually installed  for freeze-
prevention in the event of operating upset,  such as a prolonged no-flow
condition, rather than as the primary method  of maintaining a minimum
operating temperature or to  heat up  the  fluid.   The capability and ease
of remote thawing is also important  in many  situations.  The designer
must weigh these advantages  against  the  risks,  costs of electric heat
tracing  systems, and alternate freeze-protection methods.   They are more
attractive where the freeze-up time  is  short and where  the lines cannot
be blown clear  or drained.
          A  variety of electric heat tracing systems and products are
available  [33].  Resistance-type cables  and  wires are available for
installation within pipes  or for exterior tracing [34],  Small-diameter
metal  pipes, such as service lines,  can  be heated or thawed by induction
heating  from an alternating  current  in  a wire wrapped around  the pipe
which  induces eddy  currents  within the  pipe  [35].  Skin-effect current
tracing, which  requires  only one source  of power and control, may have
application  for long  steel  pipelines [36].  The most common electric  heat
tracing  systems used are  zone-parallel  and self-limiting continuous
parallel heating cables  and  strips [37].  They contain separate conductor
wires  and  resistance  buss  wires or conducting material in  the  same  casing
so  they  produce a  constant  heat output  per unit length, and can be
conveniently cut to the  desired length.   Maximum lengths are  usually 75 m

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                                  15-19
to 200 m, depending on  the  type  and  heating  capacity,  although a 400-m,
13 W/m-cable is available.   One  type has  a carbon-filled polymeric
heating element with  self-adjusting  properties that decreases heat output
as the temperature increases.  This  cable will not burn itself out or
overheat plastic pipes,  and  the  heat output  modulates, to some extent,
with temperatures along  the  pipe.
          For maximum heat  transfer  efficiency,  heating cables can be
installed within pipes.   The coating and  joints  of only a few cables,
such as mineral insulant (M.I.)  resistance cable,  are  approved for
installation within pipes or for submerged conditions.  In-line cables
are more practical for  long  water  supply  pipelines or  similar
applications because  valves  and  other such fittings must be bypassed.
They may be subject to  vibration damage when fluid velocity is greater
than 1.2 m/s [38], and  the  cables  must be removed  to clean the pipes and
when some types of pipe  repairs  are  made.  Heating cables are more
conveniently and commonly located  on the  pipe surface.  The capacity of
such heating cables should  be  increased by a factor of 1.5 for insulated
metal pipes [38], unless flat  or wide heating strips or adequate contact
between the cable and the pipe,  preferably with  heat transfer cement, is
maintained.  Since the  thermal resistance of plastic is significant (125
times that of steel), the heat tracing capacity  for plastic pipes must be
increased.  Hence, Schedule  40 pipe  up to 150-mm diameter and Schedule 80
pipe up to 75-mm diameter typically  require  1.4  times  the exterior heat
tracing capacity of a steel  pipe with the same volume  of insulation [39],
Exterior cables for pre-insulated  pipe are commonly installed within a
raceway or conduit attached  to the pipe surface, which facilitates
fabrication, installation,  removal and replacement.  In this
configuration, the air  space and poor contact of the heating cable with
the pipe can further  reduce  the  heat transfer efficiency, and for plastic
pipes the heat input  may need  to be  two to six times that for a heating
cable within the pipe [40].   It  is difficult to  make the joints in the
exterior heating cable  channel watertight, as is required for most cables
and/or their joints when used  underground.
          The location  of the  heating cable  is not significant for
insulated water pipes,  unless  it is  loose within a channel, in which case

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                                  15-20
placing it on top will  improve  the  contact  and  heat  transfer efficiency.
For above-ground pipes, heating  cables  are  placed  in the bottom quadrant
for mechanical protection.  The  cable is  usually located on top of buried
water pipes for easier  access [41]  but  for  partially full sewer lines the
cable is best located in  the bottom quadrant.
          Plastic pipes,  insulation and the electric heat tracing system
itself must be protected  from overheating unless the self-limiting
heating cable is used.  For conventional  cables, a high-temperature
thermostat cut-off  is usually installed and set at about 30C, and the
sensor is placed on  the surface  of  the  heating  cable.  For plastic pipes,
heating cables with  an  output over  12 W/m are  not  advisable unless
manufacturers of pipe and cables concur.
          To provide freeze-protection, automatic  control systems must
activate the electric heat  tracing  system at a set point above 0C to
provide some lead time  and  allow for variances  in the temperature
detection sensitivity of  the  thermostat and sensor.   To provide
economical operation, the controls  also cut off the  power supply when
heating is not required.   These  controls are often a major cause of
malfunction and wasted  energy.   Mechanical thermostats with capillary
tube  sensing bulbs  are  limited  to about 5 m in length and temperature
control is only possible  within a few degrees.   Electronic thermostats
are much more sensitive but  they are expensive.  The resistance sensors
they  use can be located any practical distance from the controller and
the system can be selected to maintain  fluid temperatures within 0.1C.
This  type of system, which is  commonly used in Greenland  [38], allows the
utility system  to be reliably operated  at near-freezing temperatures,
which reduces or eliminates  the raw water pre-heating requirements, the
utility system  heat losses,  and the need for recirculation.  The sensors
must  be located with care to  provide proper control, freeze-protection,
and prevent the waste of  energy.  To accurately measure the fluid
temperature,  they should  be put in a pipe well or attached to  the pipe
surface with heat transfer cement,  particularly for plastic pipes.  They
should be located where the lowest  pipe temperatures within the section
being controlled are expected,  such as at exposed windswept areas or
shallow sections.

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                                  15-21
          Sometimes heating  cables  are  installed  without thermostat
controls and they are manually  operated.   They can be left on throughout
the period when freezing  can occur  but  this  wastes energy.  In some sit-
uations manually operated heating cables  are used for thawing only.  For
complex piping or temperature conditions,  primarily industrial operations,
a single ambient temperature sensor and thermostat control have been used.
          The electric heat  tracing must  maintain at least 0C at the
lowest ambient temperature conditions.   The  minimum capacity required
must compensate for the pipe or utilidor  heat loss and heat transfer
inefficiencies, and include  a safety factor.  In  some cases, the capacity
will be increased to shorten the time required to thaw the pipe or pipes
if they become frozen.  The  performance of various heating cables within
a service connection utilidor are illustrated in  Figure F-3.  Commonly
used capacities are 8 W/m for service connections and 12 to 25 W/m for
mains.  Typical installed cost  for  heating cables and controls is $30/m.
15.4.5    Friction
          The amount of heat generated  by friction depends on the flow
rate, fluid viscosity, and the  pipe size  and roughness.  Friction heating
is negligible for smooth  (new)  pipes with fluid velocities less than 2
m/s, which is about the desirable upper limit for flow in pipes, but for
high fluid velocities it may be significant  [42],  Since this energy is
supplied by pumping, deliberately increasing the  velocity (friction) is a
very inefficient method of heating.  Equations for friction heat input are
presented in Figure 15-13.
15.5      Utility Systems
          Many thermal considerations must be based on the characteristics
of the total utility system  rather  than any  single pipeline, cross
section, or portion of the system.   Some  of  these considerations include:
the efficient integration of freeze-protection of service lines and the
less freeze-susceptible mains;  the  identification of trunk and subdivision
pipelines that require recirculation to maintain  a flow; and the decisions
related to the necessity, timing, and location and method of heat input.
These considerations must be assessed in  conjunction with alternatives and
factors that influence the thermal  design including:  the location of

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                                  15-22
pipes above or below-ground, under roadways  or  at  the  back of  lots;  the
depth of bury; the selection of insulation  thickness,  if  any;  and  alter-
natives such as non-gravity sewer systems and non-fire flow water
systems.  Some of these options are only appropriate  for  certain  physical
or climatic conditions.  Large utility  systems  may combine various
strategies or use different alternatives within the  serviced areas as is
economical or necessary.
          The thermal design must also  be a part of  the  physical  planning
and staging of development.  This is  particularly  important for  recircula-
tion systems, which must be looped, to  avoid stretches of pipeline
without connections, and temporary connections  or  over-building  (see
Sections 2.4.3 and 6.5).
15.5.1    Thermal analysis
          Thermal analysis of a large water distribution  system  with many
loops, recirculation pumps and intermediate heating  is much more complex
than the analysis at one cross-section  or for a single pipeline  or loop
in a recirculating system.  For large systems,  simultaneous hydraulic and
thermal analyses must be performed to determine the  flows and  water
temperatures at junctions and within  each pipe  length under various water
demand and ambient temperature conditions.   This analysis lends  itself to
computer solution [43,44],  Features  such as circulation  pumps and check
valves require rather sophisticated hydraulic models which can be com-
bined with the analogous thermal  equations  to estimate flow and  tempera-
ture patterns.  Of particular concern is  the identification of locations
or sections of the system  that experience little or no flow, flow
reversals, low-temperature and short  freeze-up  times.  The benefits and
strategic location of circulation pumps and heat input can be quickly
assessed.  Large  systems are  usually  best operated with different temp-
erature zones, and many pipes, such as  trunk mains,  will  have sufficient
demand  flow and freeze-up  time  that recirculation  and/or heating will not
be necessary.
 15.5.2    Operation
          The design of the  utility system, including storage,
distribution, circulation  and  heating,  must allow for maximum operating
flexibility and adjustments,  based  on actual operating requirements and

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                                  15-23
experience.  Procedures  for  emergency  situations  such as prolonged power
failure, freeze-up, and  start-up  during  the  winter,  as well  as heating,
circulation, draining, thawing  and  other  cold  regions characteristics
must be clearly outlined  in  an  operator's manual  [45],  Regular
surveillance, monitoring  and  recording of flows,  heating,  and fluid and
ambient ground or air  temperatures  must  be conducted to maintain and
improve the thermal performance,  and  to  indicate  potential problems.  In
some cases, soil and pipe movements may  be measured.
          Temperatures can be remotely measured  with sensors such as
thermocouples, resistance temperature  detectors  (RTD) and  thermistors
[46,47],  The latter are  commonly used because  the  lead wires can be of
practically unlimited  length, and the  off-the-shelf  accuracy of 0.1C to
0.25C can be improved by simple  calibration if  desired.  They are
rugged, but must be protected from  moisture.  A multi-cable  can be used
to carry the wires from  many sensors.  Heat  flux  transducers that measure
heat loss directly are available.  These  various  sensors can be monitored
with portable or fixed meters,  or recorded on  strip  charts,  printout or
magnetic tape.  Frost  penetration is  indicated  by a  colour change in a
0.01% solution of methyl  blue in  a  clear  plastic  tube inserted into a
casing in a bore hole.
15.6      Foundations  for Pipelines
          Frost heaving  and  thaw-settlement  are  more significant
foundation considerations than  the  foundation  load-carrying  capacity.
Frost heaving and thaw-settlement may  have conflicting solutions.  In
some cases, above-ground  piping may be necessary  but buried  utilities are
usually preferred (see Section  2.5.5.4).   The  method of installing
utilities can be selected after careful  study  of  the local conditions, in
conjunction with geothermal  analysis  of  installation alternatives.
15.6.1    Buried utilities in permafrost  areas
          Heat loss from  buried warm  pipelines  and  thermal disturbances
resulting from their installation will cause thawing that  is greater than
the natural thawing in undisturbed  areas. Possible  thaw-settlement of
ice-rich foundation soils requires  that  special  attention  be given to the
thermal regime and the stability  of the  soils  and piping.   The degree of

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                                  15-24
concern and countermeasures depends upon  the  thermal  sensitivity and ice
content of the permafrost.  For example,  at locations  where  the  mean
annual ground temperature is  just  below  freezing  (-2C to  0C),  it is
often impractical to prevent  complete  thawing of  permafrost  once the
surface vegetation has been disturbed.   For this  reason, utilities in the
discontinuous permafrost zone are  usually designed  for thawing  and
possible settlement [48,49],  In the high arctic, ground temperatures are
colder and thawing is more easily  prevented.   In  considering buried
utilities, a distinction must be made  between the relatively small and
cool water and sewer pipes, and large  utilidors  or  high-temperature
heating pipes.  With the latter, the foundations  of nearby structures can
be adversely affected.  It must also be  kept  in  mind  that  thaw-
settlement is only significant where permafrost  contains ice lenses and
excess ice content and the following considerations should not  be applied
to other permafrost conditions.
          Measures to prevent unacceptable settlement are:  reducing the
thermal influence; replacing  ice-rich  foundation  soils; anchoring pipes;
and freezing foundation soils [50].
          The thermal influence of water and  sewer  pipes can be
controlled by placing insulation around  or below them.  Insulation will
reduce the rate of thawing and  the settlement of  pipes in  ice-rich
permafrost.  This is indicated  by  the  results of  a  test loop which are
illustrated in Figure 15-6.   With  practical  thicknesses of insulation,
the heat loss can be reduced  such  that it is  no  longer the criterion for
the practicality of installing  buried  utilities  in  ice-rich permafrost.
For large or hot conduits  in  warm  permafrost, the insulation requirements
for complete permafrost protection tend  to become excessive, but moderate
amounts of insulation result  in a  significant reduction in the  rate of
thaw  [52],  Heat loss and  thermal  influence  can  be  reduced by minimizing
the surface area of insulated pipes  and  utilidors,  lowering the operating
temperature of the water  pipes, and  restricting  the temperature of
wastewater discharges.  The  placement  of pipes further from the depth of
maximum thaw will also  reduce thawing.  The  relative effects of insula-
tion  and depth of bury, which can  be  estimated for  simple  conditions from
equations in Section  15.9,  are  illustrated in Figures 15-7 and 15-8.

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                                     15-25
               0 C Isotherm
            1  Start (November, 1968)
            2  After 5 months (April, 1969)
            3  After 9 months (August, 1969)
   fs^f '''.*.'    '.' r .":'.'    v
              1.2m

  Active layer

0C	*	^J	1
    Permafrost
                           Mean annual ground
                           temperature (TG)^  -0.5C
 750 Pipe -uninsulated
        r
          0
        -20
        -40
                                     Initial location
                                     Final location
               o
        r60  ^f
              "5.
        -80  &
                                -100
                               V't?1;* "/'''"''.'. ".''"'/'.'.'''''.''. .'"''
                               ' ..V .Vjj  ', .. .'.'. -WC? '.. '^-
                                           Active layer
                                                                             0C
                                                                Permafrost
                                  75 0 Pipe  insulated
                                  with  50 mm polyurethane
FIGURE 15-6.   THAWING AND  SETTLEMENT  OF BURIED  PIPE  TEST LOOP
                 IN ICE-RICH  PERMAFROST,  BETHEL, ALASKA [51]
           0  Q2 04 0.6 0.8 1.0
                                   Mean  annual ground  temperature  (TG) = ~3.3C
          0.2

          0.4

          0.6

        0.8

       Q. 1.0

       Q  1.2

          1.4

          1.6

          1.8

          2.0
                 ..<>


200 0 Pipe
Fluid temperature 12.8C
                                                       Active layer
                                                Normal active layer depth
                                    Active layer with pipes
                     Insulation thickness (mm)
                     (kr= 0.021 Cal/m-h-C)
                                   Soil properties
                                   Va= leookg/m3
                                   kf = 1.5Cal/m-h-0C
                                   kf = 1.9Cal/m.h.C
                                   W = 25%
              Note' With no insulation, thaw depth under pipe = 4.3 m

FIGURE 15-7.   EFFECT OF INSULATION THICKNESS ON  THAW  PERTURBATION [50]

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                                   15-26
5.
Q
        0
       0.2
       0.4
       0.6
       0.8
       1.0
       1.2
       1.4
       1.6
       1.8
      2.0
       2.2
       2.4
       2.6
         0  0.2  0.4  0.6  0.8  1.0
                               Mean annual ground temperature (TQ) = -5C
                              i .^.:: "".	"'.'	.;  .
                              ' . ..;.; .); ;. O. .;.-.^.- '. V-"-'' .:.?.'<>;. . ;_
                 200 0 Pipe
                 65 mm Polyurethane insulation
                -Fluid temperature (Tw) = 10C
Soil properties
Bd= 1600 kg/m3
kf = 1.9Cal/m- h-C
kt = 1 5Cal/m-h-C
w= 15%
                                               Active layer
             Normal active layer depth 
            T- -r -r -i
            0.9 and 4.6
                             Active layer with pipe
               > Depth of bury of pipe              Permafrost
FIGURE  15-8.  EFFECT OF DEPTH-OF-BURY ON THAW PERTURBATION [50]
The effects of changes in surface conditions,  groundwater  movement,  and
soils  due to the  installation  of  utilities  and other developments are
more complex and  difficult  to  predict.   Sophisticated  computer programs
can be helpful [53,54],  It may be necessary to install  utilities only
during periods when the air temperature  is  below freezing  in order  to
reduce the thermal  disturbance, including heat input from  backfill  and
open excavations.  Groundwater and fluid from breaks flowing along  a
trench can increase thawing and,  in pervious soils,  impervious backfill
or  cut-off walls  every 50 to 200 m may be required  [11,55].
           Ice-rich foundation  soils must be pre-thawed or  replaced  to  the
maximum depth of  expected thaw.  Natural or artificial pre-thawing  may be
used  in the discontinuous permafrost  zone,  usually  as  part of the overall
development strategy.  More commonly,  soils are mechanically excavated
and replaced with compacted unfrozen  soil.
           Limited thawing can  be tolerated  if buried rigid pipes  or
utilidors are anchored to the  permafrost.   Pile supports [2] or

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                                  15-27
horizontal beams [56] can be used.  These must  extend  beyond  the maximum
thaw bulb and into the permafrost  sufficiently  to  ensure  anchorage.
These alternatives must consider the  thermal  disturbance  created by  their
installation, and frost-heaving and overburden  stresses  on the piping
between the supports.
          Refrigeration of  the foundation is  possible  but it  is complex [52,
57],  In Russia, some large utilidors with  central heating networks  are vent-
ilated during the winter to refreeze  and cool the  foundation  soils that
thawed the previous  summer  [58],   A major problem  with these  open utilidors
is groundwater infiltration and movement along  the trench [59].
          In most cases, some  thawing and differential settlement must be
anticipated, and the pipe and  joints  should be  selected  with  this in
mind.  Brittle pipe  materials  such as asbestos  cement  must not be used.
Strong ductile pipes, such  as  welded  steel, which  can  tolerate consider-
able deformation without rupture,  have  been successfully used [60].
15.6.2    Frost effects
          Frost heaving effects must  be considered for pipes  and
appurtenances located within the seasonally freezing and  thawing zone in
both seasonal frost  and permafrost areas.   The  two primary methods to
reduce heaving effects on pipes are deeper  burial, and over-excavation and
replacement with non frost-susceptible  soils  within the  trench.  Where
adequate backfill material  is  not  available,  it may be necessary to
construct utilities  above-ground.  Flexible pipes  and  joints  may be
necessary where differential movement  is expected, such  as at building
connections (see Figures 7-13  and  7-14).  To  reduce the  heaving force,
appurtenances such as fire  hydrants,  which  protrude through the freezing
zone, can be encased in an  oil and wax  collar (see Figure 6-16), wrapped
with polyethylene, and/or backfilled  with non frost-susceptible soil.  At
Norman Wells, NWT, where frost heaving  is severe,  metal  manholes were
fabricated in an inverted cone shape  to reduce  heaving forces [61].
          Frost penetration significantly increases earth loading on
buried pipes [62,63] and coupled with live  loads,  can  cause beam breaks
where pipe bedding is not uniform  or  the pipe has  inadequate  strength and
ductibility.

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                                  15-28
15.6.3    Above-ground pipes
          Above-ground utilities have  been  used  where  access  is
necessary, where excavation or backfill material would be  costly,  and
where disturbance of permafrost is  potentially hazardous.   Piping  can be
installed at the ground  surface within berms, on gravel pads,  or  on posts
or piles.  The design of  piles is similar  to  building  foundations  but,
because of the light loads, except  perhaps  for thrust  blocking,  the major
design criterion is to provide sufficient  anchorage  to resist  frost
heaving.  In permafrost  areas, piles of 4  to  12  m may  be required, the
shorter piles being used  where the  active  layer  is thinner [64],
Unanchored surface piping must allow for ground  movements  due  to  frost
heaving.  Surface drainage must be  considered since  ponding and  erosion
can adversely affect the  thermal regime, frost heaving and the foundation
soils.
15.7      Materials
          Unsuitable materials are  a significant cause of  failure  and
these often relate to their thermal performance  or characteristics.  Of
concern are:  the thermal expansion with temperature change and  freezing;
the change in thermal properties with  moisture and freezing;  the  effects
of freeze-thaw cycles; and, the influence  of  temperature on strength and
durability.  Other considerations are  essentially similar  to those in
warmer climates.  Composite structures,  such  as  pre-insulated  pipes and
utilidors, and appurtenances  must be compatible.  Since environmental and
design conditions are varied  and often opposite  properties are desirable,
no material is universally applicable. General  data on materials is
available from manufacturers, but comparisons are often difficult and
those characteristics which are important  to  cold regions  may not be
emphasized or available.
15.7.1    Piping materials
          Although some  northern engineers prefer certain types  of pipe,
virtually every  type of  pipe  used for  watermains and sewers elsewhere has
been used in cold regions.  The generally  desirable qualities of northern
piping materials are:  low  thermal  conductivity, low thermal expansion co-
efficient, high  thermal  inertia; resistance to  freezing damage and freeze-

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                                  15-29
thaw cycles; fire resistance; ease  of  heating  and  thawing;  convenience in
applying insulation; low  sensitivity to  deformation  of  foundation soils;
good transportability; and  low weight.   As  not all of  these character-
istics are available in one  type  of pipe,  the  selection must be based
upon the best material for  the specific  job, keeping in mind that it is
desirable to standardize  for maintenance purposes.  The characteristics
and properties of pipe materials  are presented in  Appendix  A.
          Some pipe materials, such as wood stave  pipe, which were used
in the past have largely  been supplanted by modern plastics.  The ability
to withstand movement due to thaw-settlement or frost  heaving is a major
reason for the use of ductile iron  and steel pipes.   Plastic pipe is
attractive because of its light weight,  which  eases  shipping and
installation.  For service  connections,  copper is  very popular, in part
because it can be electrically thawed.
          The thermal conductivity  of  metal pipes  is insignificant and
although the thermal resistance of  polyethylene is about 125 times
greater than that of steel,  its insulating  value is  usually not very
important when pipes are  insulated  (see  Example 15.1).   The heat capacity
of the pipe is not usually  considered  in temperature change and freeze-up
calculations but materials  with low heat capacity, such as  aluminum, would
be an advantage for pipelines designed for  intermittent flow [15],
          Thermal stress  and strain result  from changes in  the pipe
temperature.  The worst conditions  often occur during  the installation
and initial filling of pipes, or  if the  lines  are  drained and allowed to
cool when the ambient temperatures  are at  a minimum.  The maximum ambient
temperature range is naturally higher  for  above-ground  piping.  The
calculations required are:   the change in  length (Al = 1'u'AT); stress
(a = E'u'AT); and the load  (P = Aa),  where:   1 =  length of pipe;
Al = change in length; u =  coefficient of  thermal  expansion; AT = change
in temperature; E = Young's modules; o = stress; P = load;  and A = cross-
section area of pipe (see Example 15.12).
          For rigid pipes with high coefficients of  thermal expansion,
such as metal and fibreglass, it  is impractical to restrain movement
because the load would be very high.  Movement can be  accommodated by
flexible joints, expansion  joints,  expansion loops,  or  by allowing pipe

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                                  15-30
movement.  In-line expansion  compensation  mechanisms  do not  perform as well
at low temperatures and when  coated  with ice.   In  these conditions, free-
flexing bellows which have  no  sliding  parts  generally provide better
service [65],
          The expansion of  flexible  pipe,  such as  plastics,  is greater than
for rigid pipes, but their  low tensile  strength makes it possible to restrain
this type of pipe to eliminate  movement.   This can be done by:  fixing the
pipe to stationary anchors; encasing the pipe  within  rigid insulation or
casing, provided that the  insulation shear strength and bond are adequate;
or by burial, provided that the soil friction  and  weight are adequate.
15.7.2    Insulation
          Insulation of piping  and  structures  in cold regions is usually
necessary.  The appropriate type  and thickness must be selected.  The
thickness may be determined from  economic  analysis (see Example 15-11),
or other considerations such  as freeze-up  time or  building comfort.
Common insulating materials are plastics,  minerals and natural fibers, or
composite materials.  For  design  purposes, the structural and thermal
properties for the worst conditions  should be  used.  These conditions
occur after aging, compaction,  saturation  and  freeze-thaw cycles.  Other
selection considerations are  ease of installation, vapour transmission,
burning characteristics, and  susceptibility  to damage by vandals,
animals, chemicals and the  environment.
          The insulating value  of a  material depends  more or less direct-
ly on the volume of entrapped  gas in the material. If the material
becomes wet and the voids  filled  with  water, the insulating  properties
are lost since the thermal  resistance  of air is about 25 times that of
water and 100 times that of ice.  This  is  the  case when peat moss or
similar materials are used  around underground  pipes [66],  In the past,
the lack of a near-hydrophobic  insulation  made the design of piping in
moist environments very difficult [11],  and  is a major reason for the
development of above-ground utilidors  [3],  The advent and availability
of rigid closed-cell plastic  foam insulations  with low thermal conducti-
vity and high resistance to water absorption has dramatically influenced
northern utility systems.   They have limitations and  knowledge of their
properties is essential.

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                                  15-31
          Polyurethane  foam  is  used  extensively in cold regions to
insulate pipes and  storage tanks,  and  is  also  used in some buildings and
foundations.  Urethane  will  bond  to  most  materials.   Piping or other
components can be pre-insulated  or polyurethane can  be applied on-site
from the raw chemicals, which are  about  l/30th the final volume.  Field
applications are restricted  by  climatic  conditions,  and the density and
thermal conductivity will often  be higher than values attainable under
factory conditions  (see Section  5.2.2).   The  foam must be protected from
ultraviolet radiation during  shipping  and use.  Only a metal skin has
proven effective to prevent  "aging"  (the  loss  of entrapped heavy gas),
which increases the thermal  conductivity  by about 30% above the theoret-
ical minimum value  [67],  Depending  upon  the  formulation, urethanes can
have a higher flame-spread rating  than other  building materials, but they
are combustible and a flame-protective barrier is usually required by
building insurers and some building  codes.  If ignited, plastic foams
release smoke and toxic gases.   Densities over 100 kg/m-^ are
essentially impermeable, but  lighter foams, which are better insulators,
require coatings to prevent  water  absorption,  since  freeze-thaw cycles of
the moisture can lead to deterioration of the  insulation.
          Extruded  polystyrene,  particularly  the high density products
(50 kg/m^), suffer  the  least  from  moisture  absorption and freeze-thaw
[68], but the outer 5 mm of  unprotected  buried insulation should be
disregarded in thermal  analyses.   Molded  polystyrene will absorb some
moisture and should not be used  in moist  conditions.  Polystyrene is
available in board  stock or  beads.  The  former has been extensively used
to reduce frost penetration.  Beads  are  useful for filling voids in
utilidors while retaining easy  access  to  pipes (see  Figure 8-1B).
Although the thermal conductivity  of polystyrene is  higher than
urethanes, the volumetric cost  is  usually less (Table 15-1).
          Glass fiber batt insulation  is  the  most common building
insulation, primarily because it is  fire-resistant and relatively
inexpensive.  Its insulating value is  significantly  reduced when wet, and
is reduced by half  if 8% by  volume is  water.   For this reason, glass
fiber should not be used underground but  may  be considered wherever dry
conditions can be ensured.   Cellular glass  is  very water-resistant but is

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                                  15-32
  TABLE 15-1.  COMPARISON OF  INSULATION  PROPERTIES  OF  VARIOUS MATERIALS
Material
Polyurethane
New
Aged
High Strength
Expanded Polystyrene
Molded Polystyrene
Sulfur Foam
Insulating Concrete
Glass Fiber
Glass Foam
Vermiculite
Sawdust (dry)
Fine Grained Soil
Moisture 10% (Frozen)
Moisture 307. (Frozen)
Coarse Grained Soil
Moisture 5% (Frozen)
Moisture 15% (Frozen)
Water
Ice
Thermal
Conductivity (0
Cal/h-m-C
0.014
0.02
0.07
0.025-0-030
0.026-0.033
0.036
0.09 - 0.52
0.03  0 . 04 5
0.05
0.06
0.05-0.08
0.9 (0.9)
1.5 (2.0)
1.4 (1.0)
1.8 (2.6)
0.50
1.90
Density
kg/m3
30
30
65
15-45
15-30
175
300-1500
2 555
150-200
200
150-250
1600
1600
1750
1750
1000
900
Compressive Effect of Relative
Strength at Moisture Content (w) Volumetric
5% Deflection on Thermal Cost
kg/m2 x 10"1* Conductivity (k)
2 Negligable 4 to 6.5
2 Negligable
7 Nil
2-3 Negligable 3.5
0.7 - 1.8 Absorption, w= 32 max. 2
3.2 Absorption, w= 2% max.
7-60 Non-repellent
w= 8%, k= 0.06
7 (Ultimate) Nil
Deteriorates
Deteriorates
Increases
Increases


  (1) Cal/h-m-C x 1.1622 = W/m-k
seldom used because  it  is  brittle,  difficult to work with, and deteriorates
with freeze-thaw cycles.   Lightweight  insulating concrete made with poly-
styrene beads, pumice or expanded shale can be formulated with relatively
high strength and  thermal  resistance.   It can be poured in place around
piping but should  be protected  from moisture to prevent freeze-thaw deter-
ioration.
          Many other insulating materials, including new products such as
sulphur foam and UREA-Formaldehyde, may also find specific applications
in cold regions engineering.
15.7.3    Soils
          Soil thermal  properties are  discussed in many reports  [69,70,71,
72,73,74] and in this manual  they are  only considered in general terms.
These include the  thermal  conductivity, volumetric heat capacity, thermal
diffusivity, latent  heat and  strength.  These properties are necessary to

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                                  15-33
determine  the  depth of seasonal freezing or thawing, and variation  in
ground  temperatures due to surface temperature fluctuations.   They  are
also  important  in  determining heat loss from buried pipes and  in
foundation design.   In the field,  soil composition can vary drastically
within  short distances and profile, and may be altered by development.
Thermal  properties  derived from limited samples and indirect measurements
must  be  used with  caution.  Satisfactory estimates may often be obtained
by assuming the  worst  soil properties or conditions.
          In general,  the  soil thermal properties relate to the moisture
content, the state  (frozen or thawed), the size and shape of the mineral
particles, and  the  temperature.  When water changes to ice, its thermal
conductivity increases by  a factor of 4;  its volumetric specific heat
decreases by one-half; and it releases enough heat to change the
temperature of  an  equal volume of  rock by 150C.  Water content plays a
prominent role  in  soil thermal considerations because of this  behaviour
[73].   For fine-grained soils (silts and clays), not all the soil
moisture freezes at 0C, although for practical purposes all moisture is
frozen  by -20C  (Figure 15-9).  In this range, particularly 0C to  -5C,
thermal-related  properties are in  transition.
                           -10
                                                Clay
                                                Pleistocene clay
                                                Clayey silt with some clay
                                                Silty sand with some clay
                                                Sand
-20
-30
                        Negative soil temperature (C)
          FIGURE  15-9.   UNFROZEN MOISTURE CONTENT IN SOILS [72]

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                                  15-34
          The specific  heat  capacity  of  a  substance  is the  ratio of the
heat capacity of a  substance to  the heat capacity of water  and is therefore
dimensionless.  The volumetric heat capacity  (C)  is  a measure of the heat
required  to raise  the  temperature of a  unit  volume  of material by one degree.
The value for soils is  the aggregate  of  the constituents, water and mineral,
and since these are relatively consistant,  the  soil  heat  capacity is deter-
mined by their proportion.   The  only  unknown  is the  moisture content.
For thawed soil:

          Ct - YS   Cms  + Cmw _w_                                  (15-1)
                  |~
                  L
and for frozen soil:

          Cf = YS  Cms + Cmi
                               100
where: C = volumetric heat  capacity  (J/m3c),
      Ys = dry unit weight  (kg/m^),
      Cm = mass heat capacity  (J/kg*C),
     Cms = 837 J/kg'C for  dry soil  (mineral matter),
     Cmw = 4184 J/kg'C  for water,
     Cmi = 2092 J/kg'C  for ice.
          The soil thermal  conductivity (k) is  a  measure  of  the  rate at
which heat moves through a medium under a  unit  thermal  gradient.   A
satisfactory formula is  not available  in terms  of the aggregate  of the
constituents to account  for thermal  conductivity.  Values can be
determined by direct measurement, but  they are  more commonly approximated
from tables or graphs based on the soil type and  moisture content (see
Appendix C).  Thermal conductivity increases with soil  moisture,  density
and on freezing.  For example,  undisturbed dry  sand is  several times
better an insulator than moist  compacted sand,  while the  thermal
conductivity of silt is  about  half that of coarse-grained soil and
several times greater than  rock.
          Thermal diffusivity  (a) is a measure  of the rate at which a
temperature change spreads  through a material and is:
        a = k/C (m2/s)                                                  (15-3)

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                                  15-35
Temperature propagation  is most  rapid  in materials  with high thermal
conductivity and low heat capacity,  such as  rock, dry soils or
insulations.  Soils of higher moisture  content  have decreasing thermal
diffusivity; therefore,  saturated  soils will change temperature slower
than dry soils.
          The volumetric latent  heat of fusion  (L)  is the  heat which is
required to thaw (or is  liberated  on freezing)  a  unit volume of soil.  It
depends on the moisture  content  of  the  soil  and is:
          L =7S  (-!*-}   (J/m3)                                  (15-4)
                  Vioo/
Where:  L = volumetric latent heat  of  fusion of soil (J/m3),
       Lw = volumetric latent heat  of  fusion of water,
          = 334720 J/kg.
The latent heat of soil  is important in calculating the depth of freezing
or thawing.
          The physical properties  of frozen  soil  depend almost entirely
on the amount of ice the soil contains  and the  soil temperature,
particularly when it is  just below freezing  ("plastic frozen") and
unfrozen moisture is present.  In  terms of stability, the  soil
temperature is usually more important  than the  load.  Settlement
associated with the thawing of frozen  soil can  be estimated from the
moisture content and the dry unit  weight of  the soil [75],  If the rate
of thawing and generation of water  exceeds the  soil drainage capacity,
excess pore pressures are generated, the bearing  capacity  is drastically
reduced, and failure can occur [76],
          Frost heaving  results  primarily  from  the  siphoning or vapour
movement of groundwater  (moisture)  to  a freezing  front  where it forms ice
lenses.  Only a minor amount of  the  heaving  is  caused by the volume
expansion of freezing water.  The  potentially damaging  mechanisms are the
heaving and progressive  frost-jacking  of objects  within the freezing
zone, as well as settlement and  softening  (loss of  bearing capacity) of
the soil upon thawing.   The frost-susceptibility  of soils  is primarily a
function of the size of  the soil particles but  a  uniformly accepted
criterion does not exist.  Non-cohesive materials such  as  crushed rock,

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                                  15-36
gravel and sand are non frost-susceptible.   Soils  with  greater  than 3%
passing sieve size 200 (0.074 mm) should  be  treated  as  frost-susceptible
unless laboratory testing  proves otherwise.
15.8      Building and Structures
          The functional and structural design  of  buildings  and
structures that are part of cold regions  utility  systems  are similar to
conventional requirements.  Many design aspects are  covered  by  local or
national codes.  Northern  characteristics, such as transportation
requirements or the lack of skilled  tradesmen, must  be  considered to
ensure appropriate and economic design.   Building  thermal design
considerations differ from temperate  areas only in degree, while
foundations in permafrost  areas require unique  solutions.
15.8.1    Thermal design
          The shape of buildings, tanks or other  structures  cannot always
be adjusted, but the designer should  bear in mind  that  compact  cubes or
cylinders have the lowest  heat loss  of all practical shapes. Windows
have very high heat loss,  even with  double or triple thermopane, and they
should only be installed where they  are of significant  benefit  or
required.  The insulation  thickness  requirements  can be determined from
an economic analysis.  For building  walls, a minimum of 150  mm  of glass
fiber or equivalent insulation should be  used.  Air  infiltration, which
usually accounts for a significant portion of heating requirements,
should be reduced through  design and  good workmanship.  A double door
entrance reduces air and heat loss.   Humidity can  be a  severe problem and
hazard in utility buildings particularly  those  with  open  aerated water
surfaces, but these can sometimes be  covered or enclosed. Vapour
barriers must be meticulously installed to prevent air  leakage  and
moisture penetration into  the insulation.
          Buildings are often prefabricated  to  some  degree.   Walk-in type
freezers with urethane foam-insulated metal  panel  walls have been used
for small pumphouses or truck water  fill  points (see Figure  6-4).
15.8.2    Foundations
          Utility buildings and structures such as treatment plants and
storage tanks can be very  heavy and  deformations  must be  limited because

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                                  15-37
of the piping and equipment.  Conventional  bearing  and  frost  heave
considerations apply in non-permafrost  areas.   In  permafrost  areas,  the
foundation must be designed for  the  thermal and mechanical  interaction
due to construction and operation, and  allowances  must  be made for
physical and thermal changes which may  occur as a  result  of future
development or other operations.  The  primary concerns  are:   the possible
settlement due to thawing of ice-rich permafrost;  frost heaving;  and,  for
heavy structures on warm permafrost,  creep  must also be considered.   The
two general methods of permafrost foundation design are:  the active
method, which uses the foundation in  the  thawing or thawed  state; and  the
passive method, which maintains  the  permafrost. The applicable strategy
depends upon the thermal and physical characteristics  of  the  structure
and the permafrost.  In thaw-unstable soils, the most  commonly used
approach is to ensure preservation of the permafrost [77],
          Active designs may entail:  the replacement  of  ice-rich soils;
natural or artificial thawing and compaction prior  to  construction
(usually only in permeable, thaw-stable soils); and, allowing thawing
during construction and use, provided that  the  estimated  settlement  is
acceptable.  These solutions are  recommended when  bedrock or  stable
soils are at shallow depths; where settlement  is tolerable; in
discontinuous permafrost where soils  are  plastic frozen (warmer than
-1.5C); or if the retention of  the  frozen  state is not technically
feasible, such as under a reservoir.
          Passive designs include:   putting buildings  on  piles to isolate
them from the ground; building on top of  gravel pads that may include
foam insulation to reduce foundation  heating or be ventilated with ducts
through which cold winter air is  forced or  naturally flows; or the
foundation can be cooled either  by artificial  refrigeration or the use of
thermal piles.
          The design of bases and foundations  in permafrost is not dealt
with in detail in this manual, and other  references [64,70,71,72,73,74,77,
78,79] and specialists with a thorough  understanding of geotechnical and
thermal geotechnics should be consulted.

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                                  15-38
15.9      Thermal Calculations
          Unfortunatly, many of  the  thermal  problems  that  are  encountered
in practice either do not have exact mathematical  solutions  or other
complexities make precise solutions  impossible.  The  second-order  dif-
ferential equation which describes the  conduction  of  heat,  the diffusion
equation, succumbs to a limited  number  of  closed-form solutions, and  these
generally relate to geometrically simple boundaries,  relatively homogenous
materials, and steady state conditions  [80].   However,  such  solutions are
useful since their explicit nature allows  for  relatively easy  numerical
computation and encourages quantitative insight  into  thermal problems.
          The analytical thermal equations presented  in this Section  imply
severe idealizations.  The analyst must assess their  applicability for
particular problems and use the  results as a guide to engineering  design.
The analyst is advised to consider various models  and a range  of values
for physical and temperature conditions.   More accurate results are
obtained when reliable data is available.   In  many cases,  the  analyst must
be content with approximate solutions  and  it will  be  necessary to  assume a
large safety factor and/or the worst conditions  to arrive at conservative
estimates.
          It should be noted that boundary temperatures in the field  vary
continuously with both random and periodic components,  and are often  a
result of very complex heat exchange effects.   The materials encountered
in practice frequently represent rather poor approximations of homogenous,
isotropic media.  Soil, for example, is a  complex, multi-phase, heter-
ogenous medium, the behaviour of which is  further  complicated  by the  water
component, which undergoes phase transitions in the temperature regime of
concern.  Some of these physical and thermal complexities may be taken
into account by using  strictly numerical techniques to solve the appro-
priate differential equations  [53,54,81].   Even the most sophisticated
computer  programs still incorporate  many restrictive approximations,
particularly with respect  to determining the ground surface temperatures
and  the near-surface  ground  thermal  regime [81].  Further, because of  the
associated high manpower  and computing costs,  such numerical methods may
often only be  utilized  for  design projects of  a considerable magnitude.

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                                  15-iiy
          Portions of  this  section,  including  time-independent,
steady-state problems  of heat  flow in  this  section are  adapted from
Thornton [82].  As well, equations to  calculate  ground  temperatures and
depth of freezing and  thawing  are  included.  The symbols used are defined
in Table 15-2, and the  thermal  conductivity  of some common materials are
presented in Table 15-3.  Solutions  to a  number  of utility system
problems are presented  to illustrate the  computational  procedures and
typical results.
15.9.1    Steady-state  pipeline solutions
          Figure 15-10  deals with  heat flow  from:   a bare pipe;  an
insulated pipe; a single pipe  in an  insulated  box; and,  a utilidor
carrying multiple pipes.  In each  case,  some of  the major approximations,
in addition to the implied  time-independent  steady-state assumptions, are
indicated.  Some comments intended to  facilitate application of  the
formulae are also included.  Where applicable, expressions are presented
for relevant thermal resistance, rates of heat flow and  insulation
thicknesses.
          Figure 15-11  gives similar information for uninsulated and
insulated buried pipes.  In each of  these two  cases, the presence of
thawed ground around the pipe  is considered, and formulae are included
which indicate the dimensions  of the resulting thaw cylinder.
          Figure 15-12  contains expressions  for  the thermal resistance of
various shapes and bodies from  which heat loss can be calculated.
Formulae are given in  Figure 15-13 for estimating  the temperature drop
(or gain) along a pipeline  system, and simple  expressions relating to
freeze-up times under  no-flow  conditions  are included.
          To ease the  process  of computation,  numerical  values for
certain variables in some of the calculations  may  be read directly from
Figures 15-14, 15-15 and 15-16.  These curves  summarize  information
pertaining to the thermal resistance of a hollow cylinder (insulation
shell or pipe), the thermal resistance of a  soil mass covering a pipe,
and the physical dimensions of  a thaw  cylinder around a  pipe buried in
permafrost.
          Steady-state  thermal  influences in isotropic,  homogenous soils
can be summed and geometric modifications and  approximations can be made

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                                   15-40
                      TABLE  15-2.   LIST  OF SYMBOLS
         List of Symbols
   List of Subscripts
A = Amplitude
A = Thaw factor = T* arccosh Hp/rp
B =/irCf/k-p
c =/H2 - r2, m (ft)
Cm = Mass heat capacity, J/kg (BTU/lb-F)
C = Volumetric heat capacity, J/m3-K (BTU/ft3-F)
d & t = Thickness, M (ft)
D = Scaling parameter, m (ft)
E = Young's modulus, kg/m2 (lb/ft2)
F = arccosh (H/r)
h = Thermal film coefficient  (or surface conductance),
    W/m2-K  (BTU/h-ft2'F)
H = Depth of bury, m (ft)
I = Freezing or thawing index, K-s (F'h)
k = Thermal conductivity, W/m-K (BTU/h-ffF)
 = Length, m  (ft)
L = Volumetric latent heat, J/m3 (BTU/ft3)
p = Period, S(h)
P = Perimeter  (mean), m  (ft)
q = Fluid flow rate, m3/s  (ft3/s)
Q = Rate of heat loss per unit longitudinal length,
    W/m  (BTU/ffh)
r = Radius, m  (ft)
R = Thermal resistance of unit logitudinal length,
    K-m/K (h-ffF/BTU)
t = Time, s(h)
T = Temperature, K  (F)
T* =  (TX -  TG)/(TO  - TG)
u = Coefficient of  thermal expansion, m/m-K - m/m-K
    (ft/ffF)
w = Moisture content by  dry weight, %
V = Velocity,  m/s  (ft/h)
x = Depth
X = Depth to freezing  (0C) plane, m  (ft)
a = Thermal diffusivity, m2/s (ft2/h)
Y = Unit weight  (density), kg/m3  (lb/ft3)
a, y,  X  = Coefficients  in  modified Berggren equation
A - refers to Air
C - refers to Conduit
E - refers to Exterior casing
    (of utilidor)
f - refers to Frozen soil
g - refers to Ground freezing
    index
G - refers to Ground
h - refers to Heating index
I - refers to Insulation
j - denotes 1,2,3	
L - refers to Thermal lining
    (of utilidor)
m - refers to Mean
0 - refers to (Zero) Freezing
    point of water
P - refers to Pipe
S - refers to Soil
t - refers to Thawed soil
U - refers to Utilidor
W - refers to Water  (fluid)
    within a pipe
x - refers to Depth
Z - refers to Zone of thaw

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                                  15-41
      TABLE  15-3.   THERMAL CONDUCTIVITIES  OF COMMON MATERIALS
Material
Air, no convection (0C)
Air film, outside, 24 km.h
wind (per air film)
Air film, inside (per air
film)
Polyurethane foam
Polystyrene foam
Rock wool, glass wool
Snow, new, loose
Snow, on ground
Snow, drifted and compacted
Ice at -40C
Ice at 0C
Water (0C)
Peat, dry
Peat, thawed, 80% moisture
Peat, frozen, 80% ice
Peat, pressed, moist
Clay, dry
Clay, thawed, saturated (20%)
Clay, frozen, saturated (20%)
Sand, dry
Sand, thawed, saturated (10%)
Sand, frozen, saturated (10%)
Rock typical
Wood, plywood, dry
Wood, fir or pine, dry
Wood, maple or oad, dry
Insulating concrete (varies)

Concrete
Asphalt
Polyethelene, high density
PVC
Asbestos cement
Wood stave (varies)
Steel
Ductile iron
Aluminium
Copper
Unit
Weight
(dry)
kg/m3





32
30
55
85
300
500
900
900
1000
250
250
250
1140
1700
1700
1700
2000
2000
2000
2500
600
500
700
200 to
1500
2500
2000
950
1400
1900

7500
7500
2700
8800
Specific
Heat
Capacity
0.24




0.4
0.3
0.2
0.5
0.5
0.5
0.5
0.5
1.0
0.5
0.32
0.22
0.4
0.22
0.42
0.32
0.19
0.29
0.24
0.20
0.65
0.6
0.5


0.16

0.54
0.25


0.12

0.21
0.1
Thermal Conductivity
cal/ Cal/ W/m-K BTU/
cm-s-C m-h-C ffh-F
0.057
2.10

0.58

0.058
0.086
0.095
0.20
0.54
1.7
6.36
5.28
1.40
0.17
0.33
0.42
1.8
2.2
3.9
5.0
2.8
7.8
9.7
5.2
0.42
0.28
0.42
0.17 to
0.40
4.2
1.72
0.86
0.44
1.56
0.62
103
125
490
900
0.020
0.75

0.20

0.021
0.031
0.034
0.07
0.20
0.6
2.29
1.90
0.50
0.06
0.12
0.15
0.60
0.8
1.4
1.8
1.0
2.8
3.5
1.9
0.15
0.10
0.15
0.16 to
0.50
1.5
0.62
0.31
0.16
0.56
0.22
37
45
175
325
0.024
0.86

0.24

0.024
0.036
0.040
0.08
0.23
0.7
2.66
2.21
0.58
0.07
0.14
1.73
0.70
0.9
1.6
2.1
1.1
3.2
4.1
2.2
0.17
0.12
0.17
0.07 to
0.60
1.7
0.72
0.36
0.19
0.65
0.26
43
50
200
375
0.014
0.50

0.14

0.014
0.020
0.023
0.05
0.13
0.4
1.54
1.28
0.34
0.04
0.08
1.0
0.40
0.5
1.0
1.2
0.06
1.9
2.4
1.3
0.10
0.07
0.10
0.04 to
0.35
1.0
0.42
0.21
0.11
0.38
0.15
25
30
115
220
(1)  Values are representative
    properties.
of materials but most materials have a variation in thermal

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Sketch


Assumptions
Thprmal
Resistance
Rate of
Heat Loss
Insulation
Thickness
(qiven Q)

Comments
(a) Bare Pipe

Air Film -v -^

fr* ^\--~PlpeRp
NSa^ogSX
^ Water Film
RW
Thin walled pipe (i e rp  2 r^)
Rwis negligible Rp^ RA
Rp = (rp- rw)/ (rp+ rw) -a- kp
C-r T \0 25
%_i) w
RA = 1/27j-rPhA
7 5
N = 0.23Btu/h-ft4-F"
W = /12.5V -I- 1 for V= miles/ h
N = 1.12J/s-mr-C?
W = / 0.56 V + 1 for V = m / s
Q = (TW-TA)/RC
N/A

Often, for metal pipes, Rpmay be neglected.
If Rpis significant, the expression above
for hAwill generate an overestimate of Q.
If TA * Tw switch TA and Tw in the
expression for hA.
(b) Insulated Pipe

/*"" "^N.
/"x^^^s^X TA
(vA)
R -S^C^^;/

All thermal resistances but that of the
insulation are neglected.
RC = Rl = ' 2^k,
Ki^p)A if <^2'?
Or given ^ / rp and kj; read off
Rjfrom graph
0= (TW-TA)/R,
r,-rp= rp{exP[277k,(Tw~TA)/Q]-1}
= Trkj(Tw- TA)Q if riS2rp
Or given Rtand kj, read off rj / rpfrom graph

The neglected thermal resistances given
in (a) may be included if desjred.
Estimate a value for the insulation
surface temperature and calculate
hA and Rfl Interate
(c) Single Pipe in a Box
/-Thermal Lining
'A F-~.
Insulated or 	 /~^ ^- Exterior Casing
-"Bare"- ^Q)^ ' RE
TU  :
" T PLJ
.^ r- PE ^Ir-'E
Convection ensures the temperature inside the utilidor,
Ty, is uniform. Utilidor air films neglected.
Calculate R& the thermal resistance of the interior
conduit by
using (b) if insulated or using (a) if bare and replacing TA
in the formula for r^ by an estimate for Tu ( s Tw)
RL= tL/PLkL RE= tE/PEkE
RU  RL+ RE
R = Rc+ RU
T (TW/RC) + (Tfl/Fy
'U - (1/RJ-+ (1/RJ
If bare pipe, iterate TU
Q = (Tw-Tfl)/R
Obtain REand Rcas above
tu^L^Q^1-^-^]
If bare interior pipe, iterate Ty, Rcand
hence tL

The value of hfl, and hence RA, is fairly insensitive to the
choice of TU, and so one iteration on TU is usually
sufficient. Often REmay be neglected. Similar
calculational procedure may be performed for pipes and
utilidors of different cross-section.
(d) Multiple Pipe Utilidor

/-T, ...
TA TU/^Vf"R1 /~R3
(@J >^

Rut
Same as (c).
Calculate R for each pipe as in (c) to get Rj,
(J= 1,2,3, )
Calculate Ryas in (c)
T _ j 
-------
                      (a)  Bare, No Thaw
                                  (b)  Bare, With Thaw Zone
                                               (c)  Insulated, No Thaw
                                                (d)  Insulated, With Thaw Zone
Sketch
                                IB I
                                        'HP-
                     (x,y)
Assumptions
 Neglect all thermal resistances
 except that of the soil.
Same as (a), but accounting for the different
conductivities of thawed and frozen soil
Neglecting all thermal resistances except those of the soil
and insulation Outer surface of insulation assumed to be
isothermal, r, - rp  2rp
 Or  Given HP/rp,
 Read off arccosh (Hp/rp) from Figure 15.15

 Hz = c coth A    rz = c csch A

Or. Given A;
Read off Hz/c and rz/c from Figure 15.16
(if A ^ 0.2, use Hz/c = rz/c = 1 /A)

 R,,R, andRs(= Rt + Rt) as given m(d),
 but with r,  replaced by rp.
RI as given in Figure 15.10 (b)

Rs as given in (a), but with rp replaced by r,

T    T    Ri (Tw - TG)
h - Tw	R  + R	

For known Tw, TG,  and Rs, the minimum insulation
thickness to prevent thaw (le. T, = To) is given by:


"i = ~r    T   ^s
       'r>  In
                                               R! asgiven in Figure 15.10 (b)
                                               Tw, T', c, Hz, rzandRsasin(b)butwithrP
                                               replaced by r, and using-

                                                  A  = T'  [ arccosh (HP/rP) + 2jr k, R, ]

                                                               Ri(Tw-TG)
                                                                                                                          T, = Tw -
                                                                  (kt/k,)RI
                                               Also-
                                               R, = [ arccosh (HP/r,) - arccosh (Hz/rz ] / 2 n k,
                                                  = [ln(HP-rz/r,-Hz)]/2wkt   ifHzs2rz

                                               RI = [ arccosh (Hz/rz) ] / 2 TT k,
                                                  = [ In (2 Hz/rz ) ] / 2 TT k,  if Hz 5 2rz

                                               Or. Given Hp/r, and Hz/rz; Read off arccosh
                                               (HP/r,)and arccosh (Hz/rz) from Figure 15.15.
                                                                                                                                                                                       Ul
                                                                                                                                                                                        I
                                                                                                                                                                                       U>
 Rate of
 Heat Loss
 Q  =
     Tw - T0
                                Q =
                                             where  R  =
                                                                             arccosh (Hp/rp)
                                                            2 irk,
                                                                       Q  =
                                                                                                                       Q =
                                                                                               T'   
                                                                                               Tw ~
                                                    Or To evaluate Rg, use Figure 15.15
                                                                                                                                                     (kt/k,)R,
Insulation
Thickness
                                                                                           For no thawing outside the insulation the minimum
                                                                                           insulation thickness is given by:
             N/A
                                               N/A
                                                                                           Or:  Given R| and k,;
                                                                                               Read off r|/rpfrom Figure 15.14
                                                                                       Given Hz or rz calculate Hz/c or rz/c and use Figure
                                                                                       15.16 to evaluate A. Then use Figure 15.15 for
                                                                                       arccosh (HP/r,)

                                                                                       R i = [ (A/T') + arccosh (HP/r,) ] / 2 TT k,

                                                                                       r, - rp as in (c) but with R, replaced by R, from above.
Comments
 For  calculations of heat loss
when there is a temperature
gradient in the  soil and  Hp>2rp,
TGmaybe replaced  byTHp,the
undisturbed ground temperature at
the pipe  axis depth. For an upper
limit on heat toss  use ks = k,,
otherwise use ks  = (k, + k,) / 2.
                                                    The thawed zone is a circle in cross-section
                                       May be used to approximate (d) if k, = k, and/or rz = r,,
                                       and thaw zone parameters are not required. Use ks = k(
                                       or ks = (k,+ k,)/2asin(a).
                                                                                                                                          Often the above expressions for Rt, R, and Rs
                                                                                                                                          are not required
                              FIGURE  15-11.    STEADY  STATE  THERMAL EQUATIONS  FOR  BELOW SURFACE  PIPES  [adapted  from 82]

-------
                               15-44
Condition
Square
insulation
Rectangular
insulation
Eccentric
cylindrical
insulation
Two buried
pipes
Buried
rectangular
duct
Surface
thermal
resistance
Composite
wall
Sketch

^4 1
k-a 1

(3>  j

i /ol\
si K ri; \
V ^x 7
 ^ ^TG _
7%i?^T
K3) 0i
UP^
-. .,- TG 
| :*^^StfR:v"
H---. .- ..-. -- 
-L la %s
P

b
_._.A_.1._
TG h0 H0
?:ivr:^'-v^;;*';' t '""
k
Ks
k1 k2
^^
h'^
-.-X.|--X2
Thermal resistance
n ^ In 1 nft
R - a^k, ln 18 2rp
P 1 In/ ^ S^
R 27tk lnUr ^1
b/a S b/a S b/a S
1.00 008290 200 000373 400 697x10"6
125 003963 225 000170 500 301x1Q-7
150 001781 250 000078 i i
175 000816 300 000016 oo 0

< 7(r2+r,)2 - s2 + V(r2-r,)2-s2
R -   In 	
2Kki Vfr2*r1)2-s2- V(r2-r,)2-s2
1 ,rrrn-h ri2 + r22-s2
2TTk, 2r,- r2
Where H,s3r, , H2*3r2 and ps3(r, + r2)
l 2H1 - In 2H2 - I /(hi+h2)2+P2
r, r2 ln/(h h)2+n2
P i
R^ 2Ttko
, /(h,+h2)2-fp2
V (h^hg)2* p2
r r 1
In 2H1 - In 2H2 I l /(hi*h2)2*P2 I
'n n ln r2 [^(h.-h,)2.^ J
Rl-'= 2TVkc
|n 2H2 = In/(h1+h2)2 +P2
r! V^-h^+p2
n 1 m a5H
/ h \ ' 025 075
ks(57 + J|) b -a
Surface thermal resistance between ground
and air can be approximated as the
equivalent thickness of the underlying soil
equal to
H - KS
H"^
R  J-+ J- +^l + ^2
R h, h0 k, + k2
FIGURE 15-12.  STEADY-STATE THERMAL  RESISTANCE  OF  VARIOUS SHAPES AND
               BODIES [81]

-------
                                   15-45
 Heat Loss and Temperature Drop
 in a Fluid Flowing Through a Pipe
                            Freeze-Up Time For a Full Pipe
                            Under No-Flow Conditions (V = o)
                                           Length,
 Fluid mean velocity,
   	.
   Fluid flow rate,
   q(=V-irrw)
rw-*-[Q] Fluid volumetric heat capacity, C  Latent heat, L  ~\1
    yj-----
                        - Input fluid temperature, T,
                                                       I
Output fluid
temperature, T2
                                     Exterior (ambient) temperature, TA
                                     Thermal resistance of unit length, R
 Comments: The above sketch is schematic. R and TA appearing in these equations can be replaced by the
            thermal resistance and corresponding exterior  temperature for any shape or configuration.
 D  = irrw  V-C-R
 Calculate^ or T2,Given R, T, or T2, TA

 TI=  TA + (T2-TA)/  exp(-//D)

   = TA + (T2 - TA) / (1 +1/D)  if^/D z 0.1


     T2-TA+(T1-TA)exp(-i/D)
 Calculate R, Given T,, T2, TA

 R =/?rrw*.V-  C ln[(T2-TA)/(T1-TA)]

    = /(T, - TA) / TT rw2  V  C  (T, - T2) if/fD == 0.1

 Calculate V, Given T,, T2, TA, R

 V =//7rrw'.R-  C  Intfo-TiJ/O", -TA)]

    = M -TA)/7rrwz.V.C(T, -T2)   if|/D==0.1

 Calculate Heat Loss (Q), Given T1 or T2 , TA, V, R

 Q = (D/RX^-T^I -exp(-//D)]

    =(//R)0"i-TA)

    = D/R (T2-TA)

   Calculate Friction Heating, Given V, f
 Q, = F-r^-V-f
 Where:    Q, = BTU / h  ft
           F = 0.2515BTU/ft"
           r = ft
           V = ft/h
           f = friction head loss, ft / ft length
           Not significant for V < 2.3x10" ft / h
 or        Q{ = J / s  m
           F = 3.074x10<  J/m4
           r = m
           V = m/s
           f = friction head loss, m / m length
           Not significant for V a 2 m / s
                            Freeze-Up Times; Given R, T, , TA

                            Assume that thermal resistance of the ice, as it forms,
                            and the heat capacity of the pipe and insulation are
                            negligible.

                            Design Time (Recommended)
                               tD = Time for the fluid temperature to drop to the
                                   freezing point.

                                 =  TT-r^-R-  C ln[(T1-TA)/(T0-TA)]
                                              tor[{T1-T0)/(T1-TA)]<0.1
                            Safety Factor Time
                              tSF = Time for the fluid to drop to the nucleation
                                    temperature. Same as tD but  with To
                                    replaced  by -3C.

                            Complete Freezing Time
                              tF =  Time for  the fluid at freezing point, 0C,
                                    to completely freeze  solid.
                                 =  7r-rw2-R-L-/(T0-TA)
                            Calculate R, Given a No-Flow Time
                            Design Choice
                              RD= time/TT-r^. C  -InfCT,-TA)/(TO-TA)]

                            Minimum Resistance
                              RSF = same as RD but with TQ  replaced
                                    by -3C.
FIGURE  15-13.   TEMPERATURE DROP  AND FREEZE-UP  TIME IN PIPES
                    [adapted  from  82]

-------
                                       15-46
                                          Thermal Conduct.v.ty (k)"  3.0  Cal/h-m-'C
0
       l-l    1-2   1-3   1-4  1-5  1-6  IT  1-8  1-9 2-0   2-25   2-5   2T5  3-0      3-5     4-0    4-5   5-0
           FIGURE 15-14.   THERMAL RESISTANCE OF  A HOLLOW CYLINDER

-------
                            THERMAL  RESISTANCE  h-m-C/Cdl
                   ro
                   01
                         01
                         O
o
o
Ol
o
8

Ui
 I
      ro
      01
CO
H
>
2!
n
M
   CO


X  <

>  o
CO
CO

o
o

M
O
W
00

IS3
      01
      o
      al
      CO
      o
      (0
      o

-------
    4-0
    3-0
 N
   2-0
 N

I
    1-0
                           1-0
2-0
3-0
4-0
                                                                                                        5-0
                                                                        -P~
                                                                        00
              FIGURE 15-16.   DIMENSIONS OF A  THAW  CYLINDER AROUND A PIPE  BURIED IN PERMAFROST [82]

-------
                                  15-49
to these basic equations.  For  example,  a layered  soil can be represented
by an "effective"  soil  thickness  with  the same  total  thermal resistance.
as the layered soil.
          When pipes are buried below  the influence of short-term air
temperature fluctuations,  the ground temperatures  around the pipeline
resemble a slowly  changing series of steady-state  conditions [58],  This
is ilustrated in Figure  15-17.  The heat loss  from deeply buried pipes
can be calculated  from  steady-state equations  for  a cylinder of material
around a pipe if the fluid temperature and the  soil temperature at a
known distance from the  pipe are  measured, and  the soil and insulation
thermal conductivities  are known  [84,85,86],   Heat loss from deep pipes
can also be conveniently estimated by  replacing the ground surface
temperature in the steady-state equations with  the undisturbed ground
temperature at the pipe  depth [24] (see  Example 15.3).
          Heat loss from a buried pipe over a  time period can be
calculated from the Heating Index during that  period  (see Example 15.3).
This is the sum of the  degree seconds  (k*s) between the pipe fluid
temperature and the ambient temperature.  Thus:
          Heat Loss =   Heating Index                  (J)             (15-5)
                      Thermal Resistance
                    a 2^((Pipe Temperature - Ambient Temperature)      (15-6)
                                  Thermal Resistance
15.9.2    Subsurface temperatures
          Ground temperatures are determined by:   the air (or ground
surface) temperatures and  their variations; the thermal influence of
nearby water bodies, buried pipelines  or other  structures; heat flow from
the interior of the earth; and  the soil  thermal properties.  There are a
multitude of mathematical  solutions to geothermal  problems which
incorporate various simplifications but  are useful and accurate enough for
many foundation problems.  Many of these solutions are of a specialized
nature and application,  and are not presented  in this manual.
          Steady-state  ground temperatures beneath a  building or water
body can be calculated  from equations  [87], geometric [88], or graphical
solutions [89],  The effect of  a  sudden  change  in  the ground surface

-------
                                  15-50
                    Ground temperature (C)
           -6-4-20   24   6    8   10
           Oi  i   i  i  i  i
         100
     i
     &
        200
        300
                                  Mean temperature around pipe
                               Mean temperature of undisturbed ground
                                               1
                                       Mean annual air temperature 5.5C
     FIGURE 15-17.  GROUND  TEMPERATURES  AROUND BURIED WATER PIPE AT
                    YELLOWKNIFE,  NWT,  CANADA [66]
temperature can be  simply  calculated when the influence of latent heat is
not involved or assumed negligible  [70,80],   A similar graphical solution
is available for  the  temperature  field surrounding a cylinder (pipe) which
undergoes a sudden  change  in  temperature [90],
          Air or  ground temperatures can often be  reasonably estimated as
a sinusoidal temperature fluctuation which repeats itself daily and
annually.  This temperature pattern is attenuated  with depth and, in a
homogeneous material  (soil) with  no change of state, the temperature at
any depth and time  can be  calculated from the equations in Figure 15-18.
This simple solution  indicates  the  trends found in actual ground
temperatures but, in  practice,  they can be significantly modified by the
effects of latent heat, differences in frozen and  thawed soil thermal
thermal properties  (conductivity  and diffusivity), non-homogenous
materials, and non-symmetrical  surface temperatures because of seasonal
snow cover, vegetation, and other local climatic influences.  No
analytical closed-form solution which considers these effects exists, but
numerical computer  solutions  which  can take some of thesefactors into
account are readily available (for  example [52,53,54,81]).
15.9.2.1  Temperature and  thawing around a buried pipe.  Steady-state
temperatures around a pipe (real  or equivalent) can be easily determined
from equations, but there  is  no analytical solution for a sinusoidal

-------
    S
    
-------
                                                          ^. Active layer (A)
                                                                                   TG    To
Tx=TGMT0-TG)e'B(x-A)

     for x^A
 (forx=o IE: below pipe)
                                     B =
           ^K^"

            kf-p
 calculate from steady state equations

  in  Figure 15-11.
Steady state ground
temperatures with pipe
                                                              TX = TG+ (T0-TG)  e"B(x"A) + (T,-TG)-
                                                                    Hp+i+c\
                                                                    Hp+rrc;
                                                                                                In
                                                 Ul
                                                 I
                                                 01
                                                 t-0
for  i = 1, 2,3 ...     F = arccosh

                     =  In 2Hp/rt  for  Hp ^ 2rl

                   *_  VTG
                                                T  =
Maximum ground temperatures
in permafrost beneath active layer
            Estimate of thawing beneath pipe
       FIGURE 15-19.   GROUND TEMPERATURES  AND THAWING  AROUND BURIED  PIPES IN PERMAFROST

-------
                                  15-53
15.9.2.2  Depth of freezing or thawing.   The  depth  of  freezing or thawing
of soil or the ice thickness  on water  bodies  is  best  obtained by field
measurements, but they can be estimated  using one  of  the  many analytical
solutions in the literature [71,80,90,91,92,93],   Because of the assumptions
necessary in these analytical solutions,  such as a  step change in surface
temperature and/or neglecting the  soil temperature  changes,  they
generally overestimate the maximum freezing  isotherm  depths  for the given
conditions and are,  therefore, useful  in engineering  computations.  They
are generally Neuman  or Stephan-based  solutions  which have the form:
          X = m.fl7= m./t                                     (15-7)
               ^/ O    A/
where:  X  = depth of freezing or  thawing,
        m  = coefficient  of proportionality,
        Ig = ground  surface freezing (If) or  thawing  (It) index (Ks),
        t  = freezing or  thawing  period  (s).
          The following equations  incorporate various assumptions, but are
accurate and handy for specific  conditions.
                                                               (15-8)
                      2k  I
          X  ,  I	J	_                            (15-9)
               L + C Tm-  To + if]
X-fcdV,
Vw v
/2k  I /
V 8l
01 T -'--'-
^kl - Ig ~ 2kx
L2
C-I \
                                                    - 1d     (15-10)
                             8L -  t /                            (15-n)
                                                               (15-12)

-------
                                  15-54
where:    k = thermal conductivity  of  the  material  above  the  freezing
              isotherm, kf for  frost penetration  and  kt for  thawing
              calculations,
          L = volumetric latent heat of  the  material  undergoing  phase
              change (Equation  15-4),
          C = volumetric heat capacity of  the  material  above  the freezing
              isotherm, Cf or Ct  (Equations  15-1,  15-2),
         Tm = mean annual  site  temperature,
         T0 = freezing  point,
          d = thickness of layer  of material,
          X = a correction coefficient which takes  into consideration the
              effect of temperature change in  the  soil, and  primarily
              accounts  for the  volumetric  specific  heat effects.  It is a
              function  of  two parameters,  the  thermal ratio  (a)  and the
              fusion parameter  (y), and  is determined from Figure 15-20.
                   CT   - T  \    CT   - T  V t
               o _ V m     o/  _  V m    o/
               a -   T       -      -
                       s            e
          T   =  I  /t,  surface freezing or thawing index divided by the
          s    g
               length of  that period.

          Subscripts  f and  t  refer  to  freezing  and  thawing,  and  subscript
1 and 2 refer  to the  surface  layer  and  the  underlying material.
          Equation 15-8  is  the  Stephan  solution for a homogenous material
with a step  change in surface  temperature.   This is modified in  Equation
15-9 to account  for  the  temperature  change  in the freezing or thawing
soil.  Equation  15-10 is  a  two-layer solution of the Stephan equation
which is  useful  for  calculations  involving  snow cover, a gravel  pad or a
board of  thermal insulation,  in which  case  the  surface layer has no
latent heat  and  the  equation  is simplified.   Equation 15-11  is a close
approximation  of the  Neuman solution when  the ground temperatures are
near-freezing  [92],   Equation  15-12, the modified Berggren equation, is
perhaps the  most commonly used  solution for  soils [93].

-------
                                  15-55
                        0.0
                      1.0
                      0.9
                      0.8
                      0.7
                   o
                   o
                   I  0.6
                   o
                   Q>
                   O
                   O  0.5
                      0.4
                      0.3
   Fusion parameter p
0.1    0.2     0.3    0.4
                                                        0.5
                   FIGURE 15-20.  CORRECTION COEFFICIENT
It should be noted that, with high moisture content  soils the X
coefficient approaches  unity, the simple Stephan  solution.   In northern
climates where  the mean annual temperature is  near  or  below freezing, the
thermal ratio approaches zero and the X coefficient  is greater than
0.9.
          In very  dry soils, the soil warming  or  cooling can be
significant and  should  be included [94].  Multi-layered soil systems can
be solved by determining that portion of the surface  freezing or thawing
index required  to  penetrate each layer.  The sum  of  the thicknesses of
the frozen or thawed  layers whose indices equal the  total index is equal
to the depth of  freeze  or thaw.  The partial freezing  or thawing index to
penetrate the ntn  layers is [95]:

-------
                                  15-56
                              /n-1
          I  =   ^   dn        Z   R + Rn 1                    (15-13)
          ^n     	      I           
                     2         y  i        2
where:  In = the partial  freezing  or thawing  index required to penetrate
             the nth layer,
        Ln = volumetric latent  heat  in the ntn layer;
        dn = thickness  of  the nt"  layer,
        X  = the coefficient  based  on the  weighted average values for
             U down  to  and  including the nth  layer,
   n-1
    2i   R = the sum of the  thermal  resistances of the layers
             above  the  nth  ]_averj  anc[
        Rn _ dn; the thermal  resistance of the nch layer.

The solution of multi-layered systems is facilitated by tabular
arrangement of the  intermediate values.  The  penetration into the last
layer must be  solved by trial and  error to match the total freezing or
thawing index  at the site  (see  Example 15.13).
          It is necessary to  determine the temperature condition at the
ground surface to  determine  subsurface thermal effects, including the
depth of freezing  and  thawing.   Since air temperatures are readily
available, but surface  temperatures  are not,  a correlation factor which
combines the effects of radiation,  and convective and conductive heat
exchange at the air-ground  surface is used:
          Ig = n    Ia                                             (15-14)
where:  Ig = ground surface freezing or thawing index,
        Ia = air  freezing or thawing index, and
        n  = n-factor,  ratio of the surface and air temperature  indices.
The n-factor  is very significant in analytical ground thermal
considerations [96].  It  is highly variable and is usually estimated  from
published  observations  such as those values suggested in Table  15-4.

-------
                                  15-57
                  TABLE  15-4.   SOME EXAMPLES OF n-FACTORS [97]
                                      n-FACTORS
       SURFACE
THAWING
FREEZING
COMMENTS
Snow
Pavement free of snow & ice
Sand and gravel
Turf
Spruce
Spruce trees, brush
Above site, cleared,
moss surface
Stripped, mineral soil
surface
Spruce
Willows
Weeds
Gravel fill slope
Gravel road
Concrete road
Asphalt road
White painted surface
Peat bales on road
Dark gravel

0.35
0.37
0.73
1.72






1.74
0.76
1.44
1.15
1.0
0.9
2.0 0.9
1.0 0.5
to 0.53 0.55 to 0.9
to 0.41 0.28
to 0.78 0.25
to 1.26 0.33
0.76
0.82
0.86
1.38 0.7
1.99
2.03
,1.96,2.70
,0.98,1.25
,1.72,2.28
,1.40,1.73
General application
General application
General application
General application
Thompson,
Fairbanks
Fairbanks
Fairbanks

Manitoba
, Alaska
, Alaska
, Alaska

Inuvik, NWT

Fairbanks
Fairbanks
Fairbanks
Fairbanks
Fairbanks
Fairbanks
Fairbanks

, Alaska
, Alaska
, Alaska
, Alaska
, Alaska
, Aslaska
, Alaska
          Ice thickness  on  water  bodies  may be estimated from the
previous depth of  freezing  equations  or  from Equations 15-7 with the m
values in Table  15-5  (see Example 15.14).   Snow cover has a
significant insulating effect  and can significantly reduce the maximum
ice thickness.  The ice  formation can be greater th calculated if the
weight of snow or  the lowering  of the water level causes cracks in the
ice and water overflows  onto  the  surface.   This water is drawn into
the snow and the mixture  refreezes and bonds to th original ice.  This
snow ice appears white or frosty,  whereas  pure wat ice appears clear
or black.

-------
                                  15-58
        TABLE 15-5.  SOME EXAMPLES  OF m-FACTORS  FOR ICE THICKNESS [98]
    m-Factor
      ? x 10~5
       Conditions
10.4 - 11.0
    9.3
8.1 - 9.3
6.7 - 7.5
4.6 - 5.8
2.3 - 4.6
Practical maximum for ice not covered  with snow
Windy lakes with no snow
Medium-sized lakes with moderate  snow  cover
Rivers with moderate flow
River with snow
Small river with rapid flow
      * x 8625 = ft/0F?'h?
        x 60   = m/C?*hJ
15.10     Example Problems
          The following  example  problems  are  presented to indicate the
application of thermal equations  to  solve some of the thermal problems
encountered in utility system  design.
          Various units  of measure are  still  in common usage and this can
lead to some confusion and errors.   Most  of  the equations presented in
this section can be utilized with any  system  of units as long as the
units are consistent.  The analyst is  encouraged to work in S.I. units
and Table 15-6 lists conversion  factors to S.I. units.  Example problems
in metric, S.I. and British units are  presented.

-------
                15-59
TABLE 15-6.  CONVERSIONS  TO  SI  UNITS
To convert from:
Area
circular mil
foot2
inch2
Dens i ty
pound/ foot3
pound/inch3
Energy and Work
kilo joules (kJ)
British Thermal Unit (BTU)
calorie (cal)
Calorie (Real or Cal)
kilowatt - hour
horsepower - hour
Flow Rate
foot3/second
foot3/minute
foot3/hour
Imperial gallons/second
Imperial gallons/hour
U.S. gallons/second
U.S gallons/hour
litres/second
Force
kilogram - force
pound - force
Heat
Heat capacity
BTU/lb-F
cal/g-C
Cal/kg-C
k J/kg-K
Latent heat
BTU/lb
cal/g
Cal/kg
kJ/kg
Thermal conductivity
BTU/h-ft-F
BTU-in/h-ft2-F
cal/s-cm-C
Cal/h-m-C
Thermal resistance
h-ft: F/BTU
s-cm- C/cal
h-m- C/Cal
Length
inch
foot
mile
Mass
ounce
pound
ton (short, 2000 Ib)
ton (metric)
litre (water, 4C )
to

m2
m2
m2

kg/m3
kg/m3

J
J
J
J
J
J

mf/s
3 /
m Is
m3/s
m3/s
m3/s
m3/s
m3/s
m3/s

N
N


J/kg-K
J/kg-R
J/kg-K
J/kg-K

J/kg
J/kg
J/kg
J/kg

W/m-K
W/m-K
W/m-K
W/m-K

K-m/W
K-m/W
K-m/W

m
m
m

kg
kg
kg
kg
kg
Multiply by:

5.0671 x 10~10
0.0929
6.4516 x 10"1*

16.018
27680.

0.001
1054.4
4.184
4184
3.6 x 106
2.6845 x 106

0.028317
4.7195 x KT1*
7.8658 x 10~6
4.5459 x 10" 3
1.26275 x 10~6
3.785 x 10" 3
1.0514 x 10-6
0.001

9.80665
4.4482


4184
4184
4184
0.001

2324.6
4184
4184
0.001

1.7296
0.14413
418.4
1.1622

0.5782
2.390 x 10"3
0.8604

0.0254
0.3048
1609.3

0.02835
0.45359
907.18
1000
1
To convert from:
Power
BTU/second
BTU/hour
cal/second
cal/hour
Cal/second
Cal/hour
foot pounds force/second
horse power (550 ft-lb/s)
horse power (electric)
Joules/second
Pressure or Stress
atmosphere
bar
foot of water
inch of water (4C)
inch of mercury (0C)
pound-force/inch2 (psi)
kilogram- force/ centimeter2
kilogram- force/meter2
kilo pascals (kPa)
pascal
Temperature
Temperature interval
C
F
Temperature
C
F
Veloci ty
foot/second
foot/hour
miles/second
miles/hour
kilometers /hour
Viscoci ty
Dynamic
pascal -second
centipoise
pound-force-seconds/foot2
Kinematic
centistoke
foot2/second
Volume
acre-foot
barrel (oil)
foot3
gallon (U.S.)
gallon (Imperial)
litre
yard3
to

W
w
w
w
w
w
w
w
w
w

N/m2
N/m2
N/m2
N/m2
N/m2
N/m2
N/m2
N/m2
N/m2
N/m2


K
K

K
K

m/s
m/s
m/s
m/s
m/s


N-s/m2
N-s/m2
N-s/m2

m2/s
m2/s

m3
m3
m3
m3
m3
m3
m3
Multiply by:

1054.4
0.2929
4.184
1.1622 x 10~3
4184
1.1622
1.3558
745.70
746
1

101325
100000
2989
249.08
3386.4
6894.8
98066.5
98.066
1000
1


1
5/9 or 0.5556

C + 273
(F + 459.7) 5/

0.3048
8.4667 X 10 "*
1609.3
0.44704
0.27778


1
0.001
47.880

1.0 x 10"6
0.0929

1233.5
0.15899
0.028317
3.7854 x 10~3
4.5459 x 10 "3
1000
0.76455

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                                             15-60
EXAMPLE 15.1
Calculate the rate of heat loss (per unit length) from a plastic pipe of outside diameter 166 mm and inside
diamter 136 mm whose thermal conductivity is 0.36 W/m  K and is encased in 50 mm of polyurethane foam of
thermal conductivity 0.023 W/m  K when the pipe contains water at 5C and the above ground pipe is exposed
to an air temperature of -40C and the wind speed is 25 km/h   (7 mis).
SOLUTION:
r, = (166/2) + 50  = 133, rp = 166/2 = 83
From Figure 15-14
for rt/rp = 133/83= 1.6
and kt = 0.023; Read off:
        R, = 3.3m-K/W
Assume RP = negligible
    and RA = negligible


   Q  =  5 ' <-4)   =13.6
            3.3
      =   14W/m
                                             From Equations  in Figure 15-10(a), (b)

                                                       In (133/83)
                                               Rr   =
                                              RP  =
      2'77-0.023

       In (83/68)
      2.77-0.36
                    = 3.26 m - K/W
                       = 0.09 m  K/W
                                             Estimate the insulation surface temperature (Ts) to be
                                             at -35C, a value close to TA.
                                             Note: W = J/s, N = 1 .12, W = 0.56, V = 7m/s
h
       r_35
=1.12[   o
                                                                      0.25
                                                                           _
                                                                          /(0.56. 7)+ 1=6.15
                                            RA = 11(2 - 77  0.133  6.15) = 0.20 m  K/W

                                                                          0.20
                                             Ts =  -40+ [5-(-40)]
                                                                     0.20+3.26+0.09
                                      = -37.5C
                                             Further interation gives Ts = -37C
                                             and RA = 0.22 m  K/W

                                              Rc = 0.22 + 0.09 + 3.26 = 3.57 m  K/W

                                              Q   =  5-(-40)    =12.6 = 13 W/m
                                                        3.57
NOTE:
The thermal resistance of the pipe and the air film could be neglected in this case of a well insulated pipe. If
there was no wind, Ts =  -35C, RA = QA* and Q = 11.9 W/m.
EXAMPLE 15.2
Calculate the rate of heat loss (per unit length) for the pipe in Example 15.1 if the pipe is buried at a depth of 1 .22m
 in soil with a thermal conductivity of 2.0 W/m  K when the fluid temperature is 5C and the (steady state)
ground surface temperature is -40C.

SOLUTION:
From Example 15.1 : RP = 0.09 m  K/W and R! = 3.26 m  K/W
FromFigure 15-16forHP/rP= 1.22/0.133 = 9.17;  obtain Rs or since HP >2rP from Figure 15-11 (a):
  RS  =
  Rc = 0.09 + 3.26 + 0.23= 3.58 m  K/W

  Q  =  5 ~ (~40)   =12.6 = 13 W/m

NOTE:
The thermal resistance of the soil is relatively small compared to that of the insulated pipe and in this case it
could have been neglected. In practice, the main effect of the soil is to dampen out the extreme temperature
fluctuations (daily or annually) at the ground surface and a mean ground surface temperature of -40C is
unrealisticallv low for buried heat loss calculations (See Example 15.3).

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                                           15-61
 EXAMPLE  15.3
 Calculate the annual heat loss and the maximum rate of heat loss (per unit length) for the pipes in Examples
 15.1 and 15.2 when the ambient temperatures (typical of Barrow, Alaska) are:

                                 Mean Monthly Temperatures (C)
           Mean
          Annual  JFMAMJJASOND
     Air    -12.8  -28.4 -24.9 -24.0  -16.8 -11.7  -1.2   4.5    2.6    -0.2  -8.8  -15.2 -21.4
  Depth of
   1.22m    -9.7  -14.0 -15.0 -15.0  -13.8 -10.4  -8.0   -4.9  -2.8   -2.8  -3.1   -6.7 -10.0

 Minimum air temperature                       =-50.0C
 Minimum mean daily ground temperature at 1.22m  = -17.8C

 SOLUTION:
 Heating Index = 2 (Tw - TA)   for period when TA 2 T0 (When there is a risk of freezing)

   ForAir: JA = 2[5 - (-12.8)] + [5 - (-28.4)] +	(for each month)
             = 199.6C  months = 146000 K  h

 For Depth of 1.22 m:  I1-22  = 2 [ 5 - (-14.0) ] + [ 5 - (- 15.0) ] +	(for each month)
                         = 166.5C  months = 122000 K  h

 For an above ground pipe:
 From Example 15.1: Rc = 3.57 m  K/W = 3.57 s  m  K/J
 Annual heat loss = 146000 (60  60) / 3.57 = 1.47  10" J /m
 Maximum rate of heat loss = [ 5 - (-50.0)1/3.57 = 15.4 W/m
 and for a buried pipe:
 From Example 15.2: Rc = 3.60 m  K/W = 3.60 s  m  K/J
 Annual heat loss = 122000 (60  60) / 3.60 = 1.22  10* J/m
 Maximum rate of heat loss = [ 5- (-17.8) ] / 3.60 = 6.3 W/m

 NOTE 1:
 The annual heat loss from the above ground pipe is only slightly higher than a pipe buried in permafrost;
thowever, the maximum rate of heat loss (and freeze-up risk) is much higher. The relative differences become
 greater in warmer areas, particularly in non-permafrost conditions. In the extreme case, the pipe may be
 located below the maximum frost penetration therefore heating and freezing risk are nil.

 NOTE 2:
 The use of the mean daily (or even hourly) temperatures would result in a more precise (and lower) estimate of
 the Heating Index, but this is seldom warranted.

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                                            15-62
EXAMPLE 15.4
Calculate the interior temperature and rate of heat loss (per unit length) from the plywood box sketched below
which contains a 6-inch nominal diameter, Class 150 asbestos cement pipe. Assume that there is free
convection, radiation is negligible and that there is no air exchange (leakage) from the box. Temperatures and
dimensions are shown below.
SOLUTION:
PipeO.D. =7.17"
      I.D. = 5.85"
kp = 0.375  BTU/ft-h
kL = 0.02  BTU/ft-h
kE = 0.075  BTU/ft-h
                    rP = 3.58" = 0.298 ft
                    rw = 2.98" = 0.243 ft
                    rP - rw = 0.055 ft
                    and
                    rp + rw = 0.541 ft
From Figure 15-10(c):
Estimate Ty to be +35F, a value between -50F and +50F.
  RP  =
              0.055
         0.541 '-IT- 0.375
  hA  =
                  = 0.086 h  ft  F/BTU
                   = 0.613 h-ft2-F/BTU
    RA = 1 / (2  IT  0.298  0.613) = 0.872 h  ft  T/BTU
and Rc = 0.086 + 0.872 = 0.959 = 0.96 h  ft  F/BTU
    PE = 4 (2.0 + 0.75/12) = 8.25 ft
    RE= (0.75/12) / 8.25-0.075 = 0.101 h-tt-F/BTU
    PL = 4 (2.0-3/12) = 7.0 ft
    RL = (3/12) / 7  0.02 = 1.786 h  ft  T/BTU
    RU = 0.101 +1.786 = 1.887 = 1.89 h  ft  "F/BTU
         = _gp/M6)-(50/1:8gL  =1630p
      u      (1/0.96)+  (1/1.89)
Interate (Use this new value of TD and repeat the calculation)
                 0.298
                             = 0.75lvft2'F/BTU
    RA = 1 / (2  TT  0.298  0.75) = 0.712 h  ft  F/BTU
and Rc = 0.086 + 0.712 = 0.798 = 0.80 h  ft  F/BTU
   T   =   (50/0.80)-(50/1.89)   = 203<>F
    U       (1/0.80)+  (1/1.89)
Another interation gives a value of TU = 19.7 F
Hence Ty = 20 F
andQ  =
                   50 - (-50)
                                        37BTU/h'ft
                                                                      -Plywood
2'0"
                         IE3"
                                \
                          TA = -5
                          Polystyrene
                                                                       2'0"-
                  O.0 + 1.89
         orQ   =^0^50)_  .37BTU/h.tt

 NOTE:
 If the same volume of polystyrene were placed in a annulus around the pipe, the radius would be 0.79 ft and
 the rate of heat loss would be 13 BTU /h  ft.

-------
                                             15-63
 EXAMPLE 15.5

 The same configuration as Example 15.4, but including a 2 inch OD High Temperature Water (HTW) pipe
 at 250F  encased within 1.5 inches of asbestos fibre of thermal conductivity 0.04 BTU /h  ft  F.

 SOLUTION:
 From Example 15.4:  RtJ = 1.89 BTU/h  ft  F;
                    RP = 0.086 BTU/h  ft  F (for water conduit)
 The thermal resistance of the HTW pipe and the air film adjacent to the insulation are neglected. The thermal
 resistance of the HTW pipe insulation can be determined from Figure 15-15 or by equation:

 rj = (1 +1.5) /12 = 0.208 ft; rp = 1.0 /12 = 0.083 ft
  Rz=  Rl  =            ;       -3.65h.ft-F/BTU
                 2* IT' 0.04

 From Figure 1 5-1 0(d):

 Assume TU = 35F since then part of the calculation has already been done  in Example 1 5.4.
 So:  RT = 0.96 h  ft  F/BTU

    2 Tj / Rj = 250 / 3.65 + 50 / 0.96 = 1 20.6 BTU / h  ft  F
 and 21 /Rj = 1/3.65 + 1 /0.96 = 1.32 BTU/h -ft- F

         120.6 + (-50/1 .89)
       =                             51  C
           1.32 + (1/1 .89)

 (Further interation gives RI = 1 .66 and TU = 51 .3 F)

                            250  S1
 For the HTW pipe:    Q2  =  -  = 54.5 = 54 BTU/h  ft
                              3.65
 For the Water Pipe:   Q,   =   5 ~ 51    - 0.6 -OBTU/h-ft
                              1 .66
 For the Box:         QB  =  51 ~       = 53.7 = 54 BTU /h  ft
NOTE 1 :
If the air film of the HTW pipe insulation had been included the temperature at the surface of the insulation
must also be estimated and an interative analysis performed. This results in an interior temperature of
approximately TU - 45F, which is quite close to the previous simple analysis.

NOTE 2:
If the HTW pipe ceases to f