EPA-600/2-83-064
October 1983
Environmental Protection Technology Series
             DEMONSTRATION  OF SEWER RELINING
                                               BY THE
                               INSITUFORM PROCESS
                            NORTHBROOK. ILLINOIS
                               Municipal Environmental Research Laboratory
                                    Office of Research and Development
                                    U.S. Environmental Protection Agency
                                           Cincinnati, Ohio 45268

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                                                    EPA-600/2-S3-064
              DEMONSTRATION OF SEWER RELINING
                          Blf TOE
            INSITUFORM PROCESS, NORTHBROOK, IL.
                            by
                        F.T.  Driver
                        M.R.  Olson
                 Driver, Olson  and  DeGraff
                   Grant No. R-806322


                     Project Officer
                    Robert Turkeltaub
            Storm and Combined Sewer Section
              Wastewater Research Division
Municipal Environmental Research Laboratory (Cincinnati)
                Edison, New Jersey 08837
                This study was conducted
                   in cooperation with
                 Public Works Department
          Village of Northbroc* ,  Illinois 60062
       MUNICIPAL ENVIRONMENTAL PZSEAPCH LABORATORY
           OFFICE OF RESEARCH A.'£ DEVELOPMENT
          U. S. ENVIRONMENTAL PROTECTION AGENCY
                 CINCINNATI,  OHIO 56268

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                             DISCLAIMER

     Although the information described in this article has been
funded wholly or in part by the United States Environmental Pro-
tection Agency through assistance agreement number R-806322 to
Driver, Olson-Degraff & Associates, it has not been subjected to
the Agency's required peer and administrative review and therefore
does not necessarily reflect the views of the Agency and no offic-
ial endorsement should be inferred.

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                                  FOREWORD

     The Environmental  Protection Agency was created  because of increasing
public and  government concern about the dangers  of pollution to the health
and welfare of the American  people.  Noxious air,  foul water, and spoiled
land are tragic testimony to the deterioration  of our natural environment.
The complexity  of  that  environment and the interplay between its components
require a concentrated and integrated attack on the problem.

     Research  and  development  is  that  necessary  first  step  in problem
solution and it involves  defining  the probJem,  measuring  its  impact, and
searching  for  solutions.  The  Municipal  Environmental  Research Laboratory
develops  new  and  improved  technology  and  systems   for   the  prevention,
treatment  and  management  of  wastewater  and  solid   and   hazardous  waste
pollutant   discharges   from  municipal  and  community  sources,   for  the
preservation and treatment of public drinking water supplies and to minimize
the adverse economic, social,  health,  and aesthetic  effects  of pollution.
This publication  is  one of  the products  of that  research;  a  most vital
communications  link between the  researcher and the user community.

     The  work  described herein was  undertaken  to  evaluate  Insituform a
method of  lining sewers in need of rehabilitation.   Based on an evaluation
of  the  results  of the study  using the Insituform  method of  lining,  this
method has  proved  to be a viable alternative to present conventional sewer
lining methods.

                              Francis T. Mayo
                              Director
                              Municipal Environmental Research
                              Laboratory
                                     iii

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                                   PREFACE

    The requirement  by the E P A  for sewer system  evaluation surveys has
shown  that in  many  cases  the  most  cost  effective  approach  to pollution
abatement  is through sewer  collection system rehabilitation.  The increased
activity  in sewer  collection system rehabilitation  brought about  by the
funding of this  work  under  various State and Federal  grant programs has
necessitated the  search  for improved procedures.  These improvements may be
in the form of  advances  in techniques of existing rehabilitation procedures
and/or in  the development of new  rehabilitation procedures.

    In  1971 Insituform  a  state-of-the-art  method  of sewer  and pipeline
rehabilitation was developed  in Great Britain.   After four years of  testing
the first  licenses were  granted  to  British contractors.  This was followed
in 1976 by the  granting  of licenses to European and Australian contractors.
In 1977 Insituform came  to  North  America.

    The  interest in  Insituform  as  a  rehabilitation  procedure  was almost
immediate  and  spread quickly throughout North America.  The only  problem
seemed to  be the lack of data as  related to  North  American standards for
work to be performed through public  agencies.

    The  object then  of  this  study  was  to  establish  the  feasibility and
effectiveness of  Insituform lining of sewers  in need  of rehabilitation.  The
process  consists of  inserting a flexible  felt bag treated  with a thermo
setting resin  into  a sewer by means of a  static water head.   Hot water  is
then circulated in  the  line, thus  curing the  liner.  The procedure  in  most
cases  requires  no excavation which  is of  great  advantage in  densely built-up
areas.

    In order  to obtain  data  two  sections of Insituform were  installed  in  a
controlled test sewer line  which  was in need of rehabilitation.

    The   ease  of   installation   along   with   flow  characteristics  and
infiltration  of  the  sections before and  after  lining  were  documented.
Characteristics of  the  final product were determined  by removing  in-place
sections   and  specimens  made  from  job  site materials  to  run  destructive
tests.  Tests  were performed  in  an  approved laboratory.  The cost  of  this
method of  sewer lining was  analyzed in comparison to alternatives.

    The  study was limited  to Insituform  and did not compare it with  other
methods   of  rehabilitation  except  in  the   area  of  cost   and   ease  of
installation.
                                      iv

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                                  ABSTRACT

    This research  was initiated with  the overall  objective of determining
the effectivenes of a new process of lining sewers  called Insituform.

    Two  test sections  of sewer  in need  of  rehabilitation were  lined  to
evaluate both the effectiveness of the liner in eliminating  infiltration and
the  liner's effect  on  the  flow  characteristics  of  the  sewer.   Physical
characteristics of  the installed liner  were tested by  running destructive
tests on specimens made from job site materials.

    Results  of   the  liner   installation   were  evaluated   in  terms   of
effectiveness   in  elimination   of   infiltration  and   change   in   flow
characteristics/  i.e. infiltration  and  flow  studies  performed before and
after  lining.    Destructive  test results  were evaluated  in  terms  of the
physical characteristics of  the liner  material,   i.e.  tensile properties,
shear strength, etc.

    This study  is the  first  of  two studies  being performed on Insituform.
This  study was  limited to  Insituform  and  did not  compare  it with  other
methods  of  rehabilitation   except   in   the  area  of  cost   and  ease  of
installation.

    The  conclusions,  recommendations and installation procedures described
in  the  text  in   this  report  should  be  of  help to  potential  users  in
determining  the viability of this rehabilitation  technique  as  it may  apply
to their needs.   This study documents   the fact that the Insituform method
of  lining  deteriorated  sewers   is  an  effective  process  for eliminating
infiltration from  lines,  as  well as improving the hydraulics and structural
integrity of damaged  conduits.  The economical advantages of this system are
mainly dependent upon physical conditions of each application.

    This report  was  submitted in  fulfillment of Grant  R-806322 by Driver,
Olson  and  DeGraff,  Consulting  Engineers  under  sponsorship  of  the   U.S.
Environmental Protection Agency and the  Village of  Northbrook,  Illinois.

    This report covers the period May 7, 1979 to September 30,  1980 and work
was completed as of March 15, 1981.

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                                  CONTENTS

Foreword	iii
Preface	iv
Abstract 	   v
Figures	vii
Tables	ix
Acknowledgment 	   x
Abbreviations and Symbols	xi

    1. Introduction	   1
    2. Conclusions 	   2
    3. Recommendations	   5
    4. Demonstration of Sewer Relining by the
       Insituform Process, Northbrook, IL	   7
       Need for the Northbrook Lining Study	   7
       Site Selection for Sewer Lining Study by
       Insituform process	12
       Conditions of Sanitary Sewer to be Lined	15
       Flow Data	18
       Ground Water Condition	22
       Infiltration	24
       Flow characteristics  	  26
       Installation of Insituform Liner	28
       Physical Properties of Liner	57
       Cost-Effectiveness of Insituform Liner	60
       Six-Month Follow-Up Evaluation	62

Appendices

    A. Statement from manufacturer (Insituform)	63
    B. Laboratory Analysis, United States
       Testing Company/ Inc	64
                                     vi

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                                   FIGURES

Number                                                             Page

    1  Test section for sewer relining by Insituform
       process ............................  14

    2  Television Inspection - Log Test Section ME 12
       to MH #3 ............................  16

    3  Television Inspection - Log Test Section MH 13
       to MH #4 ............................  17

    4  Stage - Discharge Curves for Test Sections ...........  19

    5  Trench drawdown effect .....................  23

    6  Six-inch diameter ABS rigid pipe bypassing system .......  30

    7  Service bypass system with portable gasoline
       power pump ........................... 30

    8  Village of Northbrook Public Works Department
       performing pre-Insituform cleaning with a high
       velocity water jet ....................... 37

    9  Inversion tube complete with upper steel support
       ring and inversion shoe being raised into place
       on the inversion scaffold .................... 39
   10  Inversion tube and shoe being positioned in manhole
   11  Village of Northbrook hydrant and fire hose used
       to supply water for the inversion ................ 42

   12  Duct taped end of liner bag extending out of
       inversion elbow ......................... 42

   13  Stainless steel band being tightened on the outer
       layer or first layer of the liner bag .............. 43

   14  Preparing to lower inversion shoe with properly
       banded liner bag into inverson manhole .............  43

   15  Steps in lining with Insituform ................. 44
                                     vii

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16  Workman on right turns on water supply valve as
    workman on left restrains liner bag until
    inversion head is reached	45

17  Looking at liner bag inverting in sewer.  At 9:00
    position, note wires from thermo-couple placed
    in sewer pipe and liner	47

18  Top right shows rope wrapped around capstan and
    attached to end of liner bag.  Lower left shows
    lay flat hose used to circulate heated water
    from boiler/heat exchanger  	  48

19  Back of truck showing recirculation pump	49

20  Pneumatically-operated right-angle carbide tip
    power saw to cut out ends of liner 	  51

21  A television camera lower left faces the Insitucutter
    which is used to remotely reinstate the services.
    The cutter is controlled by an operator who views
    the cutting operation from  the television van
    pictured in the background  	  53

22  Sheeted excavation at break-in service connection
    shown after lining was installed and before
    service was reinstated 	  55

23  ABS saddle tee strapped upside down to the sewer
    pipe to simulate service connection	55

24  Service connection renewed  by the Insitucutter  	  56

25  Diagram of test setup	59
                                  viii

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                                   TABLES
Number                                                             EdgS.
    1  Hydraulic loadings prior to rehabilitation 	 20
    2  Hydraulic loadings after rehabilitation	21
    3  Trench drawdown effect 	 24
    4  Weir analysis of infiltration	25
    5  Analysis of exfiltration 	 26
    6  Manning roughness coefficient	27
    7  Typical material properties of cured Insitufom
       liner versus PVC  (Type P31)	57
    8  Insituform costs	60
                                      ix

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                               ACKNCWLEDQtfNTS

    The  cooperation of  Village  of  Northbrook,  John  Novinson,  Assistant
Village Manager, and Village of Northbrook Department of  Public Works, Jim
Reynolds,  Director,  is  gratefully  acknowledged.   We   are  particularly
indebted to Ms.  Marilyn  Khedroo, Project Coordinator, for her cooperation,
active support and  sustained interest in the project.  The cooperation and
assistance of E  P A Project Officers Robert Turkeltaub and  Richard Traver
in both the development of  the program  of study and the presentation of the
final results is gratefully acknowledged.

    The  consultant  expresses  its thanks  to  the members  of  the technical
advisory committee.

                        TECHNICAL ADVISORY CCMMITTEE

James Witt                    Leland Gottstein
Naylor Industrial             2231 Edgewood Avenue
P. 0. Box 6507                Minneapolis, Minnesota  55426
Pasadena, Texas  77506

William Thompson              Richard Sullivan
National Association of       American Public Works Assoc.
  Sewer Service Companies     1313 East 60th Street
123 Variety Tree Circle       Chicago, Illinois  60637
Altamonte Springs,  Fla.
32701

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                      LIST OF ABBREVIATIONS AND SYMBOLS
G         — gallons
GPM       — gallons per minute
GPD       — gallons per day
MO)       — million gallons per day
m or M    — meters
on        — centimeters
ran        — millimeters
1         — liters
M^       — cubic meters
         — cubic meters per minute
         — cubic meters per day
ft        — feet
in.       — inches
ft3
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                                  SECTION 1

                                IMTPCDUCnON
    The  information contained  in this  report is  the joint  effort  of the
Village  of  Northbrook,  Illinois,  U.S.  Environmental Protection  Agency,
Insituform  (Pipe and Structures)  Limited, Northampton  England, Insituform
East, Inc., Hyattsville, Maryland and Driver, Olson and DeGraff, Consulting
Engineers,  Rockford,  Illinois.   Insituform  Limited  and  Insituform East
participation  in this  study  was  limited  to that  of  material supplier and
installer respectively.

    This  research  program was  initiated with  the  overall  objective  of
determining feasibility and effectiveness  of  the Insituform method of  lining
sewers in need of rehabilitation.

    Two controlled  test sections, which required rehabilitation, were  lined
with  Insituform.  Observations and  documentation  were made  of the ease of
installation,  as  well  as  flow  characteristics  and  infiltration  of each
section before and  after  lining.  Characteristics of the final product were
determined by  performing destructive tests on  in-place sections as well as
prepared specimens.

    The description of  the equipment used  in  the installation as well  as the
description  of  the  installation  procedures,  are  meant   to familiarize
potential users  as  to the adaptability of  the process to their needs.

    Flow characteristics, infiltration data before and  after  lining, as well
as  physical  properties of  the material,  are meant to help  municipalities,
sanitary districts and  design  engineers faced  with upcoming  rehabilitation
projects determine the feasibility  of this  process  for  their  application.
Flow  characteristics, infiltration elimination data and cost  of installation
considerations  are discussed in  this report  in  an  effort  to  help  these
entities in making  cost-effective rehabilitation judgements.

    The  material properties  presented herein  are a  result  of destructive
tests made by an  independent laboratory  on  representative  test specimens,
and should be  considered along with published information in designing each
project.

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                                  SECTION 2

                                 CONCLUSIONS
     The  lining  of sewers  in  need of  rehabilitation  by  the Insituform
process   is   an  effective  technique  for   eliminating  infiltration  and
prolonging the  life expectancy of a sewer.   The finished product, in fact,
will  have   greater  structural   integrity   and  may   also  have  greater
flow-carrying capacity than  the original  sewer at the time of installation.
The fact that the in-place (in  situ) liner is void of joints between manhole
structures  eliminates   the  expectance  of   future  infiltration  or  root
ir.trusion over the  life of the  liner materials.

     This study has shown  Insituform  to be a  viable  alternative  to other
more conventional sewer rehabilitation methods.

     The  cost-effectiveness of the  Insituform product,  as well  as other
methods of  rehabilitation, must be  evaluated on an  individual basis.  The
results of  this analysis  indicate Insituform to be  most cost-effective in
the following applications of conduit rehabilitation:

     1.  Locations  where construction is very costly due to high restoration
         cost of disturbed areas.

     2.  Areas where excavating is costly due to a high water table,
         unfavorable soil conditions or extreme  depth.

     3.  Sections in which anticipated  future flow does not exceed capacity.

     4.  Areas where sewers are not readily accessible between manholes, or
         other points of access.

     5.  Instances  in which rehabilitation time  is limited due to by-
         passing requirements,  and/or loss of commerce due to
         disruption of surface  facilities.

     6.  Locations  where existing sewers are in  such a deteriorated
         condition  as to render other methods of rehabilitation
         impractical or impossible.

     7.  Areas where  resistivity  to chemically reactive types of waste
         is required.

     8.  Sites in which the conduit cross-section is irregular in shape and
         size, where conventional rehabilitation process will not serve

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         the purpose.

     Insituform is not the answer to all sewer line rehabilitation problems,
but  the  findings  of  this  study certainly have   to classify it  as   a
state-of-the-art  technique   available  as   an  alternative  to  serve  the
rehabilitation program.

     Some potential disadvantages of the Insituform Process are as follows:

     1.  Additional cost is incurred due to the need  for a thorough  interior
         inspection by remote camera immediately prior  to repair
         of that area of the  pipeline.

     2.  A degree of expertise is required of the  installer to assure that
         the resins are of suitable quality, properly mixed and
         cured and heated to  the correct temperature.

     3.  The chemically treated bag, if improperly installed, may totally
         block the pipeline to be repaired and require  excavation to gain
         access to it.  A fresh lining bag would then be needed.

     4.  In certain types of  installations, where  there are lateral
         connections to the pipe that is being lined, it is necessary to
         curtail water service until the lining has been completed.

     5.  There is presently a lack of trained personnel competent to utilize
         the process and perform the installations.

     This  study was  limited to the  Insituform  rehabilitation technique.
Comparison to alternative lining methods included  evaluation on  installation
and  fabrication  limitations associated with:  (1) cold weather; (2) length
of section;  (3)  access point; (4)  root problems;  and  (5) safety hazards and
procedures.

     1.  Cold weather  limitations for Insituform and  alternative  lining
         methods are similar  regarding the effects upon manpower  and equip-
         ment.  Cold weather  problems associated with added heat  required
         in the curing of the Insituform liner are less significant  in the
         overall process when balanced against excavation and material
         handling required with other techniques,  as  evidenced by the lack
         of lining activities in northern states during severe weather.

     2.  Historically, polyethylene slip-lining techniques have  had  the
         capability of longer single runs.   However,  in
         most cases the practical single-length sections are less
         than the physically  capable lengths due to associated
         conditions within  the actual sewer  line.

     3.  The Insituform technique requires less area  on-site than
         alternatives  in order to stage the  lining operation.
         The curing equipment can be remotely-located,  but there
         are practical limitations.  Inversion equipment and

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    materials may be transported manually to the site from a
    remote location.  Restoration is normally minimal and can
    be performed by hand.  Slip-lining can be fused remotely
    and can be installed remotely with very distinct limitat-
    ions.  Excavation equipment is required on site for
    staging pits and service reinstatement; surface restora-
    tion may be considerable.

4.  Tree root removal is a preferable preliminary step in all
    types of sewer lining processes.   The presence of roots
    in Insituform and slip-lining can act to distort the
    cross-sectional shape of the liner.  The degree of distor-
    tion, depending upon the root mass, may cause unnecessary
    strains to result in the liner.

5.  All lining techniques require a common sense approach
    to safety which is consistent with their respective
    operations and both material suppliers and manufacturers
    recommendations.

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                                  SECTION 3
                               RECOMMENDATIONS

    The  information gained during  this study  has answered  many questions
with  regard  to  the  use  of  Insituform  in   sewer  system  rehabilitation
programs.  This review has also shown the need  for additional, more detailed
analysis beyond the scope of this  report.   A  study should be undertaken to
examine the relative success or failure of existing Insituform installations
nationwide,   to   develop  a   general   assessment  of   this   innovative
rehabilitation   technique.    Head   to   head  comparisons   with   other
rehabilitation methods, considering  costs,  results and environmental impact
should be studied as a minimum.

    The development of standard specifications for Insituform  lining,  or a
guideline  for  the preparation of  said specification should  be undertaken,
with  cooperation  between material  suppliers,  installers,  engineers,  and
public  agencies.   As  a part  of the  guidelines for  these specifications,
design  concepts  should  be  made  available  to  prospective users.   Many
potential  users of Insituform lining are reluctant to  consider the product
because  of   the   limited  historical  data  available  on  United  States
installations.

    Additionally,  the flow  carrying characteristics  should be  studied in
more  detail  so that  the  flow carrying  characteristics  of  the  finished
product can be accurately predicted.

    Safety standards related to all phases of  the  installation procedures
should be developed.   Insituform installation procedures as with other sewer
rehabilitation techniques require working under many adverse conditions such
as:   nighttime  operations,   areas  not  readily  accessible,  undesirable
climate,  and all  other hazards  associated with  underground construction,
i.e.  caving, and damage to existing utilities.

    Observations  made  during the  Northbrook  installation  indicated  that
surplus  resin penetrated existing joint material.  The  stabilizing effect of
this  resin on  porous joint  material should  be determined  by appropriate
laboratory testing.

    Insituform  and  other rehabilitation  techniques  presently  in  use  are
limited,  in most  cases  to mainline  sewers.    There   is  growing evidence,
substantiated  by the  fact  projects in  many cases have not achieved their
predicted  infiltration and  inflow  (I/I)  reductions,  that rehabilitation of
mainline  sewers is causing a  migration of  the  I/I  problem to  the house
lateral, or  that  a significant portion of the problem  in fact emanates from

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the lateral.  Other  causes of I/I overestimates  could  also be attributable
to ground water  level  changes,  faulty estinates of the effectiveness of the
rehabilitation project, or infiltration migration.

    Rehabilitation of  house or  service connections  has some  problems not
present  in mainline sewer rehabilitation  in that  they are  in  most cases
accessible at only one end, are of  small  diameter,  and require working and
excavating on private property.

    A  study of  house  or service  connection rehabilitation  by Insituform
should  be  undertaken  to  determine  if  it  can become  a  cost-effective
solution.

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                                  SECTION 4

                       DEMONSTRATION OF SEWER RELDJING
                                   BJf THE
                     INSITUFOIW PROCESS, NDRTHBROCK, IL.
             NQREHBIOOK SEWER RELINING STUDY
    Many  communities  and  sanitary  districts  throughout  the  nation are
finding it exceedingly difficult  to meet new, more stringent stream quality
criteria, to maintain existing facilities, and t.o satisfactorily  service new
and existing customers with present  revenues.

    If  this  shortfall of required  funds continues,  it may pose  a public
health hazard  to present and future generations.   Oily through a series of
carefully administered cost-effective  programs can we  expect to  assure the
safety of our  future environment.   In  short we must get the maximum benefit
out of each dollar invested.

    Sewer system  evaluation  surveys have in many cases shown it  to be more
cost-effective to remove from sanitary collection  systems extraneous water
sources than to transport and provide treatment for this infiltration and/or
inflow.   Removal  of  clear  water  from  the  sewers  in  most  cases  is
accomplished  by  rehabilitation  of  various  components of the  wastewater
transportation network.

    The rehabilitation of sewer collection systems may include one or all of
the following techniques:

    1.  Grouting of deteriorating or leaking pipe joints.

    2.  Pressure grouting of manhole leaks.

    3.  Point replacement of cracked or structurally-failed
        sections of pipe.

    4.  Total line replacement.

    5.  Manhole rehabilitation by repairing and sealing.

    6.  Manhole replacement.

    7.  Sewer lining (slip-lining, Centri-line method, Insitu-
        forming).

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    8.  Replacement sewer construction.

    9.  Disconnection of illegal connections.

   10.  Control of root intrusion.

    No one  technique is best  suited for all  situations and circumstances.
In  order to select  the  technique best  suited  to  a  specific  need the
advantages  and  disadvantages  of  each must  be carefully  considered taking
into account their respective benefits and costs.

Grouting

    Grouting is the placement of acrylonitrile gel, urethane foam,  hydraulic
cement,  or  other acceptable  material on/  in,  or outside of a  sewer pipe
joint  for  the  purpose of preventing  exfiltration,  infiltration,  and the
intrusion of soil or roots through defective joints.

    Grouting techniques generally offer the following advantages relative to
other methods:

    1.  Most leaks in pipe joints can be sealed oy one of  the
        above mentioned grouting methods.

    2.  Many of the materials used in grouting are flexible/ and
        therefore sane movement of sealed joints can be accommodated
        without destroying the integrity of the seal.

    3.  Some grouting materials create impervious masses outside
        the joint by saturating and stabilizing the backfill,
        and therefore continued movement of improperly supported
        pipe may be arrested.

    There  are,  however,  certain  limitations  and  disadvantages  of  the
grouting technique:

    1.  Some grouting materials show signs of deterioration and
        shrinkage after repeated periods of wet/dry cycles,
        rendering the joint susceptible to infiltration.

    2.  Continued movement of pipe beyond flexibility limits of
        the grout material may cause seal failure.

    3.  Grout material adds little or no structural strength to
        the pipe joint.

Pressure Grouting flf M.a.nhQ.lfiS

    Pressure  grouting  of  a  manhole  is  effective   when   the  area  of
infiltration entry is small and well defined.   Pressure grouting is a quick
and economical  method of  eliminating  infiltration because all work  can be
done at one time with a single crew and setup.  Pressure grouting should not

                                      8

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be used where infiltration entry is not well defined or where the sealing  of
one entry point would merely divert the infiltration to another point.

Point Replacement

    Point replacement of  cracked  or structurally failed sections of pipe  is
the actual  excavation,  removal, and replacement of a limited number of pipe
sections  within  a  given stretch of  line  between  two  manholes.   Point
replacement in most cases  is limited  to a  nominal  length of  sewer pipe,
which generally is some multiple of the length of a single  section  of pipe.

    In many cases a given length  of  sewer between two manholes  is in good
condition  except  for one or  two pipe sections  that have  failed.   In this
case the most cost-effective rehabilitation method  is to locate and repair
only the deteriorated sections.  The  repairing of only the  defective section
not  only reduces  the  rehabilitation cost,  but also  can be done  with the
least possible disruption to surface conditions, and in many cases requires
no  bypass  pumping  or  interruption  in  service.   Point  replacement does,
however,   require accurate   location of defective   sections  by  internal
inspection  prior  to any  excavation,  and  normally has a  high cost per unit
length restoration.

    It  is  also very important when  doing point  replacement to extend the
work  to a  length that  insures  that the entire failed  stretch  of pipe  is
replaced.   Point  replacement  must also  correct the cause of the failure.
Many times  existing  bedding must  be stabilized,  and well-compacted, granular
backfill installed.

     If there are a number of point  replacements  in a given stretch of sewer
 line  it  may be  more cost-effective  to perform  total replacement  between
 manholes.  Total replacement is the excavation of an entire stretch of sewer
 line extending between one or several pairs of manholes.

     Provided  the design  and  installation  techniques  used  for repair  are
 proper, the total replacement  of a  line  provides  the opportunity to correct
 the reason for the original  failure and  assures  the total rehabilitation of
 the line.

     The cost of this method of rehabilitation may far exceed that for normal
 new construction because  the area  probably has  become built-up over time,
 thus necessitating immense restoration costs; also, service connections must
 be handled live, and upstream sewage must be bypassed.

                                     an(^ sealin
     Manhole rehabilitation  by repairing and  sealing  may consist of  one or
 more  of  the  following  structural  repairs:   (1)  manhole  rim  and  lid
 adjustment  or  replacement;  (2)  step  replacement;  (3)  invert and  bench
 repair; and (4) repair and sealing of manhole walls.

-------
    Rehabilitation  of existing manholes  is  relatively inexpensive,  creates
minimal  disruption within  the environment,  and can  usually be  done by  a
small   local  contractor   or  municipal   forces.     This   alternative   of
infiltration  control  can  be  very  effective  in   eliminating significant
amounts  of  clear water at  low unit  costs.   Normally all work  can be done
without sewer flow  interruption.

    Manholes if  properly  rehabilitated should be expected  to have a useful
life similar to  the sewer system.  Manholes in heavy  traffic areas may need
continual  maintenance  due  to vibrations caused  by the  traffic.   Minor
manhole  rehabilitation  is a means of buying time until total replacement of
the unit is necessary.

Manhole Replacement

    Manhole  replacement  is   the  removal of  an   existing structure   and
replacing  it with  a complete new unit.   This permits  the  contractor  to
correct  or allow for the  factors which initially contributed to the  manhole
failure.  New materials and construction methods should result  in a  better,
longer-life manhole than  the  original unit was when  it was first installed.

Sewer T.lning

    Sewer lining by slip-lining/  Centri-line method, or Insituforming is  the
placement, by sane  means, of a new material within  an existing  deteriorated
sewer.  When completed, the technique causes the existing conduit to nave a
complete new internal  surface, with much different flow  properties due  to
changes  in  the  pipe-roughness and  hydraulic  cross-section.   The  disruption
to the  surrounding  surface is inherently minimal in this operation;  cost is
less than  that  associated with replacement.   The  new line  normally  is much
smoother and is  impervious  to root  growth, which assures future  integrity of
the sector.   However, the problem  remains that excavations must be  made  at
each service connection  for  the  purpose  of making  reconnection,  except  in
the case of  Insituform  where  the  service connection  is renewed by  a remotely
controlled cutter.

    Sewer  lining may not  be used  in  pipe where sections  have  protruding
service  taps or are collapsed  to  the  point  that  the lining  material  is
prohibited  from  passing   until  point  repair  is  performed.   Reduction  to
inside  diameter  of  the  lined pipe  may  reduce  the  capacity  of the pipe
depending  upon  reduction  and the  uiproverrent in  the  smoothness  of   the
conduit.    Sewer  lining   is  a  very   specialized   field,   and  therefore
contractors  and  competition  may  be sonewhat  limited  in  sane  geographic
areas.

    Insituform,  a  relatively new  method of  sewer  lining in  the  United
States,   appears   to  be   a   "state-of-the-art"   improvement   in  sewer
rehabilitation.   It is felt  by sane that current methods  of lining sewer,
while effective  in eliminating infiltration,  are not  satisfactory for other
reasons,   such   as   reduction  in   hydraulic  capacity  as  well   as   the
inconvenience   associated  with  slip-lining.   Staging   requirements   for
slip-lining  necessitates  excavation for  both liner  insertion  and  service

                                      10

-------
reinstatement.   Inaccessible  areas  or  areas where  restoration  costs  are
prohibitive  are not  suitable  for slip-lining.   Small diameter  pipe  size
limitations for the Centri-line method restrict the satisfactory use of this
current  lining method.   Insituform  has the major  advantage of  generally
requiring  no  excavation  and  therefore,  very  little  restoration  in  the
installation process, even in the  course of reinstating  lateral  connections.
In  densely populated  areas,  under  permanent structures,  on the backs  of
property lines, or in roadways where surface  restoration costs or  techniques
are  prohibitive it  would seem  that a  cost  convenience  savings could  be
realized over the conventional slip-lining procedure, while  at the same time
creating  negligible  disturbance  to  traffic,  working environments,  and
existing   surface   features.   Conventional  pipe   lining  methods   are
economically advantageous in lines where carrying  capacity is  not  critical
and where there are not a significant amount  of taps.

    There  are  several reasons to  feel  that  this  system of relining  sewers
deserves  further attention.   As  previously  stated, due  to  the  fact  that
Insituform  lining  typically requires  no  excavation,  it  appears  to  be
generally  competitive  in overall cost with  standard polyethylene  liner
installations, especially in built up areas where there  are  numerous service
taps.  Further in line with  this "no-excavation" concept, inconveniences due
to  traffic control  and  rear-yard excavation can be virtually eliminated.
This  process,  in effect,  creates  a  new pipe  within  the  existing  one;
thereby, lending a degree of structural  integrity to  the outside conduit.

    Since  the  material  installed in the lining work  is  very thin  (1/8 in. [3
mm]—3/4 in.[18 mm])  and molds itself under  a static hydraulic  head against
the  walls  of the existing  sewer,  there is  virtually no  reduction in  line
size.  This fact, coupled with the increased  liner smoothness, may result in
an  increase  in the capacity of  a  section.  The absence of  an annular space
between  the existing  pipe  and  the liner  precludes any  infiltration  from
being  conducted  along the space to the  downstream manhole.  This  occurrence
is  quite prevalent with  a polyethylene liner  installation.  For a  typical
section  of  12 in.  (30  cm)  diameter  sewer, a  10.75  in.  (27.3  on)  O.D.
polyethylene liner would  be  used,  thus creating an annular space of .625 in.
 (1.6 cm) between the  liner and sewer; this, coupled with an  approximate wall
thickness  of 0.4 in.  (1.0 cm) significantly reduces the  cross-sectional area
of the conduit.  As mentioned in other sections of this  report,  ground water
may  migrate  along  paths  of  reduced  flow  resistance  (trenches,  etc.),
manifesting  itself  in the  form of infiltration  in downstream  manholes and
service  lines.   Therefore,  manholes and services should be  rehabilitated as
part of  a  total project.

    Present  Insituform installations  in  the United  States range  in size from
4  in.  (10  cm)  through 36 in.  (92  cm) and  vary in lengths  from  80 ft  (24 m)
to  500  ft  (150  m)   for  a  single inversion.   Size limitations  are  those
imposed  by  economics   and   physical   material   properties  and  handling
requirements.   Smaller diameter inversions  require greater inversion heads
of  pressurized   inversion  while  progressively  larger diameters  require
greater  boiler/heating   capacities  and  larger  diameter   inversions  also
require  mechanical  assistance in  handling the bag because  of the weight of
the bag  and  resin.   Restrictions caused  by manhole  rings can be  a  problem in

                                     11

-------
Inversions for sewers greater than 18 in.  (46 can)  in diameter because  of  the
necessity of  getting a  rigid  inversion elbow down  into the manhole.  This
problem  can  be surmounted  by removing  the ring  and  upper section of  the
manhole  or by using  top  inversion procedures  which  do  not  require   an
inversion elbow.

     Insituform can be custom-designed for each application.  The dimensions
of the "bag" can be designed per section; the lining can conform to  any type
of configuration,  whereas  polyethylene  liners are  generally restricted  to
circular cross-sections.  The  heat sensitive polyester  resin,  which  in  the
Insituform method  is  impregnated into  the felt  bag,  can also be  custom
designed to resist a wide range of chemical environments.

     One of the chief disadvantages of the Insituform process is the limited
number  of  licensed  installers  in  the  United  States.   Although   the
European-born process has been in the United States well over three  years  at
present  there are only  three installers  currently licensed by the  parent
firm,  Insituform International.   There  has  been  some talk  by Insituform
International  that  a nationwide licensing  program is to  be forthcoming  in
the  very near future.   At present,  however,  Insituform  installation  is
limited to selected  areas served by the  three installers, consequently  the
vast majority of installations are in the central, eastern seaboard  states.

     The physical properties  of Insituform as installed have not been well
documented in this nation, and with the lack of a long history of successful
installations many public agencies and potential  users  have been reluctant
to consider its use.

     Another disadvantage presently associated with this  technique  is that
there are no standard specifications for product installation and materials.
This makes it  quite  difficult  for engineers to either specify Insituform or
inspect the job performance with adequate assurances.

fiJTq ffiTJTTTOM FOR SEWER LINING STUDY By INSITOFORM PROCESS

     The  selection of  a site  for this  project was  based upon finding a
community  located   in  a  densely  populated   area  where  rehabilitation
requirements  had  been  demonstrated by  means of  an approved  Sewer  System
Evaluation  Survey to be  cost-effective.  The  community also had  to   be
willing to commit capital and manpower in order to sponsor the program.

     Northbrook, Illinois,  which is a suburb located  northwest of  Chicago,
agreed  to  pursue  this  endeavor  by   applying  for  Federal  participation
regarding the study funds.

     This  community, along with  fitting  the above description, has been
actively engaged in  bringing their sewer system  into compliance with  State,
Federal and local discharge requirements.

     Northbrook next met with their Engineer to select  a section of  sewer,
which had been previously determined by the Village Sewer System Evaluation
Survey  to have excess  infiltration, such  that  the rehabilitation  of said

                                     12

-------
section would be cost-effective  through a relining procedure.  The two most
inportant criteria used for selecting the study section was that it be in an
area which normally  experiences  extended periods  of  high ground water, and
that the actual  conduit is deteriorated  to  the  extent that clear water may
freely enter.

     Typical physical conditions of  the sewer pipe in the test section were
offset  joints,   leaking  joints,  sags,  radial cracks, lateral  cracks,  and
multiple  cracks.   The  study section  was   selected  such   that  flow  and
infiltration quantities would be  accurately monitored  and  documented both
before and after the liner was  installed.   Special consideration was given
to  accessibility  of   the  site  for  the  purposes  of  installation  and
observation by interested parties during  the  inversion operation.  This last
requirement  precludes  any  site  selection  on  private  property  and/or
rear-yard easements.

     After reviewing several sites,  the  final selection was made to use a
535 ft  (175 m) section of 12  in. (30  on)  diameter  sanitary sewer depicted in
Figure 1, located on Skokie Highway,  on the easterly boundary of Northbrook.
The  line rehabilitated is  located midway between  the edge  of pavement and
the west property line  in a grass swale.
                                      13

-------
                                                         NOTE COOK CO HIGHWAY DEPT HAS NO
                                                       RECORDS OF STORM SEWER AS SHOWN
                2-12 AR CULVERTS
                (SO en)
                                              432'- 12" DIA. O.27 %
                                        PROFILE   <'30 m - 30cm)
Figure  1.  Test  section  for sewer  relining by Insituform  process.

-------
CONDITIONS OP SANITARY SEWER TO R^

     Historical data  from the Village of Northbrook  records indicated  this
12 in. (30 cm) sanitary sewer was installed in 1962 by a private contractor.
The  Village policy  regarding Public  Works projects  at that  tine did not
require  full  time   inspection   by  Village  forces  during   construction.
Interviews with municipal employees of the period,  along with the exposure
of  services for  the  Insituform installation,  has given a  good  idea of
construction conditions  encountered by  the original  contractor.   The  area
then, as  it is today, was subject  to extended periods of high water table.
The  sewer was  constructed directly under a marginally sloped roadside ditch
in which  standing water  is  common.  Average water  table is consistently 6
in.  (15 on) above the top of the sanitary sewer pipe.  Unfortunately during
the  testing period the ground water table  was relatively low.  In addition
to the high water table, the  soil  conditions in this  location vary widely
from clay  to  silty loam, with clay the  predominant layer providing bedding
for  the sewer.  This soil condition along  with the high  water table would
tend to make  proper  trench bottom  conditions difficult  without improved
bedding.  Available  records  and  site evidence do not indicate  that improved
bedding was called for or used during  the laying of this sewer.

     The  present area  served by the two  test sections consists  of  both
residential and commercial users.  Typically the sewer flow ranges from 360
GPM  (1.4M3/min) to 580 GPM (2.2M3/min), but Village employees have witnessed
considerable  surcharging events  through this stretch  in the  recent past,
closely following precipitation.

     Prior  to making the  internal  inspection of  the  sewer, preparatory
cleaning was performed by the Village of Northbrook Public Works  Department
forces  using a high pressure water  jet.   The materials  cleaned from  each
section were  trapped at the downstream  manhole  and removed.   Investigation
of the material  removed from  the conduit  showed the presence  of clay  tile
fragments  from upstream  breakages and granular material which may have  been
roadway debris or sane sewer backfill  material.

     After  the sewer was cleaned sufficiently  to allow a representative
picture,  each section was inspected  by means of  closed-circuit  television
system.   Internal inspection revealed that the pipe in the test section had
many offset and pulled joints which were sources of visible  infiltration, as
well as radial and longitudinal cracks in many locations.  Some sections of
conduit were  cracked to the  extent  that  they were  rendered structurally
unstable.   When  the internal  inspection video-tapes were compared with the
earlier tapes  of  the sewer,  which were made some three years earlier during
the  Sewer  System Evaluation  Survey,  it was  realized that conditions had
significantly  worsened during the intervening period.  The condition of the
sewer had deteriorated to the extent  that there were sections that were no
longer  circular.   Copies of  the TV logs  are included in Figures 2 and 3.
The  theoretical  capacity of the  existing  12 in. (30 cm) diameter vitrified
clay pipe, which has  a measured slope  of 0.0026  ft  per L.F.(.26%), as
determined using the  "Clay  Pipe Engineering  Manual,"  published  by the
National Clay  Pipe Institute,  is  approximately 1.1 MO)  (4070 M-VD).


                                      15

-------
JOB NO
TELEVI

79-2O12
VIDEO TAPE NO. TAPE »\ SEC 4 OPERATOR AL GERBER
SION INSPECTION REPORT (FIELD
INSITUFORM RELINING NORT
FROM MANHOLE "A" NUMBER; 	 2
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-------
JOB NO
TELEVI

79-2012
SIGN INSPECTION REPORT
VIDEO TAPE NO. TAP? Jl xrr in CPERATOR AL GERBER
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Figure 3.  Television Inspection - Log Test Section MH #3 to MH #4

-------
     This theoretical capacity is based upon the following assumptions:

     1.  Sewage is considered to have same flow characteristics as
         water.

     2.  The sewer is assumed to have uniform flow conditions.

     3.  The sewer is classified in hydraulic terminology as an open
         channel.

     4.  The slope and cross-section of the line is constant
         throughout.

     5.  The roughness of the line is constant throughout and the line
         is assumed to have a roughness coefficient of 0.013.

The  actual capacity of  the  test sections  are  reduced  somewhat due  to
isolated  inconsistencies,  such  as root  intrusions,  offset  joints,  broken
pipe, invert deposits, alignment variations,  etc.   Results from the limited
number of  measurements were scattered.   Therefore,  the actual  Manning "n"
was assumed to be 0.014, giving a section capacity of 1.0 MO) (3800 M3/day).

FLOW DATA

     In an  effort to obtain typical hydraulic  loadings  of the test section
NB instruments, Model GR portable flow meters were installed in the upstream
(MB  2)  and downstream  (MH  4)  manholes for  a period of two  weeks prior to
liner insertion,  and then reinstalled for a  period of two weeks after the
rehabilitation  was  performed  (see Figure 4).   Each meter  was continuous
reading and recording on a seven-day strip  chart.   The depth readings from
the strip charts were converted into flow quantities using Mannings Equation
(detailed  on   page  25,   after  physically  field   determining  the  flow
cross-section and  slopes  of each line.  Daily  Average Flows (DAF) and Peak
Daily Flows (PDF), along with daily contributions from sewer users tributary
to the test segments, are presented in Tables 1 and 2 of this report.  These
Tables  indicate  the monitoring results  both  before and  after Insituform
lining.  As can be seen from these Tables the DAF through the test sections
ranges between 0.25  (925 M3/D)  and  0.4  MO3  (1480  M3/D)  with  daily peaks
reaching  approximately 0.8  MOD  (2960M3/D).   The meter  readings  at the
upstream manhole were taken to be representative of DAF due to the fact that
a  large watermain  leak was  detected within  the test  section  during the
project.  Flows from services within  the test segment  were monitored on  a
daily basis over the project period by Village of Northbrook staff.
                                     18

-------
[6475]
  1.50
[5550]
  1.25
[4625]

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  0.50
[1850]
  0.25
 [950]
        STAGE-DISCHARGE CURVES
          12  in.  (30 cm) Dia.  Sewer
                 n=0.008
    LEGEND
    MH 2-MH 3 (PRE)
	 MH 3-MH 4 (PRE)
	MH 2-MH 3 (POST)
	MH 3-MH 4 (POST.)
      0      24      6      8     10     12
           [5.08][10.16][15.24][20.32][25.40][30.48]
                DEPTH OF FLOW  (in.)[cm]
  Figure 4 Stage-Discharge Curves  for Test  Sections
                          19

-------
                        TABLE  1.  HYDRAULIC  LOADINGS  PRIOR  TO LINER INSERTION
                                                             INSITUFOHH STUDY

SEPT.
1979






27




































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PART
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CAPACITY
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1663)
990(1663)
990
99O
1663)
990(36631 	
990(3663)






99O(ICS3)





be Inflated d


eadl

I «atrl







ACTUAL FLOW
HGD (DAF)


4010(14031
4OIOI 1483)
40)0(1*831
3203(11«S1
3741(1384)
32031)185)



HI
25131929)







quant It
lei
by village or

•




GAGING STA - HH 4


.55
55
54
52
65
~7T

09


64




lea


Nort






PART
FLOH
6213
575O
5750
S64O
5200
7600
724O
6000
8160


724O




over









SLOPE
27
27
27
27
27
27
27
27
27
27
27
27




lewer


staff






CAPACITY
NGO
1 OS44(37
-------
                              TABLE  2.  HYDRAULIC  LOADINGS  AFTER  REHABILITATION
POST-INSITUFORH INSITUFORM STUDY
DATE
OCT
1979

10
11
12
13
It
15
16
17
l«
19
2O
21
22
21
24
25

27
26

30
11




NOTE

42AO
Jl_
Q

2*
26
26
27
29
32
12
1O
12
3»

11
.35
31
.28
27
32
10
26
36
36
26



X»

_»ii-
•'y
HQ ST
PART
FLOK
PACT
.115
166
166
166
155
17<
206
.206
165

211
215
2 2O
2*1
196
. I6B
.155
2O6
165
126
zee
266
166





irouru
M/C i
• MH 2
SLOPE
I
.251
251

2S3
251
251
251
253
253
251
451
24J
251
251
253
.251
253
251
2S3
2S1
243
253
233





l !
1 6U1I393II
1 601(3911 I
1 603(5931 )
1 6OK591I )
1.601(5911)
1 6OK591I)
1 601(59)1)
1 603(5911 )
1 603(5911)
1 601(5911)
1 6OK5931)
1 603(5911 )





reading* lakei
d Iron pluggli

ACTUAL FL#K
•400 (DAf)l
'Ml D*YI
' 2966(10971
2691(996)
26*1(996)
2691(996)
2*65(919)
2769(1011)
3334(1233)
3134(1233)
296611097)
113411211)
3167(1191)
3I6MI 191)
352MI1OO
3975(1470)
3142(1162)
2691(996)
24(5(919)
3134(1231)
2966(1097)
2052(759)
4617(1706)
4617(1706)
2691(996)





by Village ol
g of p«rforal
OACINC STA - M>
•5-








36
16
39
19
16
i4
3O
32
29
26
26
1O
12
32






UfIS
PAHT
FLOH
F*CT








266
266
103
3O3
266
215
165
206
174
166
126
165
206
2O6







SLOPE
*
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27






1 4,
CAPACITY
MOD
(M3/DAY)
1 656(6127)
1 65616127)
1 656(6127)
1 656(6127)
1.656(6127)
1 656(6127)
1 656(6127)
1 656(6127)
1 656(6127)
1 656(6127)
1 656(6127)
1 656(6127)
1 656(6127)
1 65616127)
1 656(612')
1 656(6127)
1 656(6)27)
1 65616127)
1 656(6127)
1 656(6127)
1 656(6127)
1 656(6127)
1.656(6127)







ACTUAL FLOW
HSDlDAF)
(M3/DAY)








4769(1764)
4769(1764)
5016(1656)
5016(1656)
4769(1764)
3892(1440)
10641 11 11)
1444(1274)
2661(1065)
2762(1029)
21201764)
1064(1111)
1444(1274)








r LOW
DIFF
HOD*
(Ml/HAV)








Ieojio6/v
1415(510
1231 (462
1251(462)
1242(459
OO63I3O)
0076(26)
O75I 1 J77
0196(136
0552 1 2O<
0946(31 3
1012(174
11711414









SERVICE
FLOH
MGOxlO
(H3/DAV)








.650(2)
1 07(1)
1 230(4)


i. 110(7)
1 0/0(3)
1 740(6)
1 160(4)
1 420(5)


1 900(7)
1 220(7)
1 640(6)







INFILTRA-
TION
MOD
(Hl/DAY)








1796501664)
14243(526)
123670(456)


-.0104101361
- OO667OI32)
073160(271 )
O3642OO42)
0566201 20<


1I92OO1441
.116520(411








•£
STO'
34
.36
71
38
16
44
46
46
.41
.42
44
39
36
.54
49
.49
46
47
.51
44
55
5O
.62



Sfl°J'








.59
52
51
51
49
.46
52
54
52
51
51
41
12
12





•OTH
gft°i'







6O
62
57
6O


«
SO
S2
6O
57


95
BO
96



Sfl0?'







136
126
121
121


««
>M
1*1
116
126


126
116
121




FALL

O
O
O
0
O
O
0
0
O
O
O 1
O
0
o
0
O
0
O
0
O
0
O
I °



DRIVER OLSON AND O1GRAFF •
1 MVIN1H •!«••! '
MOCMFOHO IIUMO1S «IIO« '
K>
            * MOST  LIKELY  DUE  TO  MANHOLE INFILTRATION.

-------
     Previous  to lining/ significant  wee weather  precipitated flows which
initiated surcharging,  thereby indicating flows in  excess of 1.0 MGD  (3800
M3/D).  Intermittent problems with the meters prohibited truly accurate flow
data/ but did  give an indication of  the effectiveness of the technique  in
reducing infiltration within the test section.  Investigations of the meters
revealed at  times  that the arms on  the units would periodically stick, and
that debris would occasionally hang up on the float, thus  creating erroneous
readings.

     Daily  flow  metering  of  the  test  section   prior   to rehabilitation
indicated infiltration within the test  section varying from 0.17  MOD  (629
M3/D) to 0.54  MGD (1998 M3/D).   These  values are  very large  for  an I/I
contribution on a segment of this length.  They can be chiefly attributed  to
a large watermain leak previously mentioned flowing almost unrestricted into
the  sewer.   Also/  the accuracy of the flow  metering devices  is  a factor.
There were  no  inflow  sources detected  within  the  test  sections.   So that
before-and-after  infiltration tests might  be more  meaningful/  the Village
officials agreed not  to repair  the watermain  leak until  after  all flow
monitoring was completed.

     Flow metering data  compiled under  ground water/ time/ flow and weather
conditions similar  to  before lining showed infiltration  after sewer lining
with Insituform to range from  0.18  MGD  (666 M3/D)  to a  negative  value  of
-0.12 MGD  (-444 M3/D).   The  accuracy of  the  flow metering devices makes
these relative differences highly questionable.  However/  the data in Tables
1 and 2  indicates a reduction in  clear water flow.  The detailed I/I tests
performed manually at  the site directly before and after  the rehabilitation
program  are  much  more  representative  of the  actual effectiveness  of the
technique.

GROUND WATER CONDITION

     To relate  the  interdependence between infiltration and relative ground
water elevation in  the study  areas,  daily  records were kept  by Village
forces  of  the  ground  water  depths   during  the   same   period  that  flow
monitoring was in progress.

     Ground  water gauges  were  installed at  the  extremities  of  the test
section, two at MH 2 and two at MH 4.  The purpose of installing two ground
water gauges at each extremity was  co  determine  the well-point effect that
occurs in  the  ground water  table  when a  trench  backfilled with relatively
permeable  material  acts as  the  means  to  conduct ground water  into  a
perforated conduit  (badly disjointed and broken pipe) in which it is carried
away with  the  wastewater.   Theoretically the further from  the trench that
the ground water is measured,  the  shallower should be the reading; thereby,
evidencing a movement of ground water toward the trench (Figure 5).  To bear
out  this  theory one ground  water  gauge was  placed in the  manhole,  with a
corresponding  unit placed  some 15  ft  (4.6  m)  from  the  manhole  measured
perpendicular  to the  trench line.  Data collected  (Table 3) indicated that
indeed the well-point-draw down phenomena does  occur in this situation even
though granular bedding was  not  used in the  installation of  the  main and
in-place  material  was  apparently  used  as  backfill.   In  some cases  the

                                     22

-------
elevation  of the ground water surface at the manhole was  more than 2 ft (61
cm)  lower  than  that 15 ft (4.6 m)  remote.  This condition can be attributed
to  the reduced  compaction  of the  backfill material  coupled  with  the
restratification of the in-place material during backfill  operation.
                                             Excavated Material
                                                   Ground  Water Table

                                             Granular Backfill

                                           7 Sewer Pipe



                                                  Granular Bedding
 Figure  5.  Trench Drawdown Effect
                                    23

-------
     •typically during  the period of flow data  collection,  the ground water
was over the crown of the sewer by 1 ft  (.3m) at MH 2 and 2.5 ft  (.75 m) at'
the downstream  manhole.  This information  is presented  in  Tables 1 and 2,
but the  level does  not fluctuate  to the  extent  that its  effect upon the
infiltration  in  the  test  section  would   be   a  meaningful  relationship;
therefore, a graph of this relationship  is  not included.
                       Table 3. TRENCH DRAWDOWN EFFECT
DATE
1979



9-18
9-22
9-24
9-26
9-28
10-16
10-18
10-22
10-24
10-26
GROUND
WATER
ELEV.IN
MANHOLE
NO. 2
88.24
88.44
89.31
89.04
88.55
88.84
88.89
88.92
88.92
89.09
GROUND
WATER
ELEV.
REMOTE

90.24
90.24
90.91
90.74
90.65
91.24
90.49
90.32
90.32
90.49
DIFF. IN
GROUND
WATER
ELEV.

2.0
1.8
1.6
1.7
2.1
2.4
1.6
1.4
1.4
1.4
GROUND
WATER
ELEV.IN
MANHOLE
NO. 4
90.10
90.20
90.20
90.10
90.20
91.06
90.50
90.50
90.60
90.65
GROUND
WATER
ELEV.
REMOTE

90.83
91.00
91.08
91.08
91.08
91.66
91.25
91.33
91.83
91.41
DIFF. IN
GROUND
WATER
ELEV.

0.73
0.73
0.88
0.98
0.88
0.60
0.75
0.83
1.23
0.76
All measurements are  in ft.  To convert  to m multiply by 0.305.
INFILTRATION

      in an effort to determine  the  effectiveness of  the  Insituform technique
upon  infiltration sources,  the following methods of study were  implemented,
taking note  that due to conditions  that prevailed, different approaches were
used  in each test section.

      On the  upstream test section  from MH 2 to MH  3,  the  upstream manhole
was  plugged  and  a 90 degree  V-notch weir  installed  in  the  downstream
manhole, also service  taps  in the stretch  were plugged and the flow bypassed
downstream.   After the flow over the weir  stabilized, flow measurements were
taken at seven-minute intervals with the  average  pre-lining  infiltration
being approximately 19,500  gallons daily (74 M3/D)  (Table  4).   The  ground
water at MH  2 during this analysis  was some  13 in.  (33 cm) over  the crown of
the  outlet piper this being much lower  than during  testing  periods shown in
Tables  1  and  2.   This  data  would  seem to  be more  reliable  than that
monitored and recorded prior to and after  the demonstration  due  to the total
section  isolation; note  that the infiltration  value shown  here is only  for
the  sewer between MH 2 and  MH 3, and that  shown  in Tables 1  and  2  is for  the
entire  section.   As  previously stated, the vast majority of the measured
clear water  in this segment was due to a  watermain  leak near MH 3. Because
                                      24

-------
of the limited time (some two hours) which was available from the  initiation
of the bypass operation  until  the insertion of the Insituform liner,  it was
not possible  to establish a  functional relationship between  the amount  of
rainfall, ground water depth and clear water flow in the sewer.
                   TABLE 4. WEIR ANALYSIS OF INFILTRATION
STK
PRE-LINING (OCT. 2, 1979)
TIME
9:53 a.m.
10:00 a.m.
10:07 a.m.
10:15 a.m.
10:20 a.m.
Ground
water
above
crown
INFILTRATION BY
WEIR GPD(M3/D)
36,000(137)
25,500(97)
19,500(74)
19,500(74)
19,500(74)



1.08 ft (.32m)
JMJH MH2 - Mflj
POST-LINING (OCT. 4, 1979)
TIME
2:24 a.m.
2:52 a.m.
2:59 a.m.
3:07 a.m.
3:15 a.m.



1.20 ft(.36m)
INFILTRATION BY
WEIR GPD(M3/D)

Flow was not
measurable —
100 (.38)





     After this test section was lined and just prior to the discontinuation
of bypass  pumping, similar  procedures to  those described  in the previous
paragraph were  used in developing  a post-Insituform value  of infiltration
within  the  section.  Barely a  trickle was noted  over  the weir  during the
second battery of tests, with the clear water contribution estimated at less
than  100 GPD.   Since  the service  connections had  not  yet been  cut and
reconnected  to  the main,  it was  deduced  that the  infiltration noted was
coming  from seepage through  the walls,  bench,  and pipe  entrance and exit
areas of MH 2.

     Test section 2, downstream of  that described in the previous paragraph
and between MH  3 and MH 4, was tested by means  of exfiltration tests.  The
reasoning behind  the  performance  of  this  type  of test  was that  a badly
damaged  storm  sewer  in  this  area  was  drawing  the  water   table  down
significantly.   Efforts to  obtain  records or  plans  of  this  storm sewer
proved  fruitless.   Attempts to  artificially  increase the elevation  of the
water table by sprinkling failed.  Therefore the section between MH 3 and MH
4 was filled with water by plugging the downstream manhole as well as MH 3
and  filling the section  from a fire hydrant while  normal flow was being
overpumped.  By measuring the decrease in the water level over time in MH 3,
it  was  determined  that  the  pre-lining  value   for   exfiltration  was
approximately 3800 GPD  (14.06 M3/D)(Table 5).
                                     25

-------
STUMl
PRE-LINING (OCT. 2, 1979)

Tine


11:05 a.m.
11:20 a.m.
11:35 a.m.
11:40 a.m.
11:45 a.m.
11:55 a.m.
12:10 p.m.
Water
Level in
MH 3
above crowr
ft(m)
3.00C.90)
2.50(.75)
2.15(.65)
Refill MH
3.00C.90)
2.60C.78)
2.33(.70)
Exfiltra-
tion Rate
GPD(M3/D)




3900(14.4)



3643(13.5)
ZHMH 3— MH 4
POST-LINING (OCT. 4, 1979)

Time


3:35 a.m.
3:50 a.m.
4:05 a.m.
4:20 a.m.
4:35 a.m.


Water
Level in
MH 3
above crown
ft(m)
3.00(.90)
3.00(.90)
2. 93 (.88)
2: 90 (.87)
2. 88 (.86)


Exfiltra-
tion Rate*
3PD(M3/D)






274(1.01)


Ground water  Not Measurable
Not Measurable
*Most likely leaking through manhole structure.

     Post-lining studies,  of  an identical nature,  showed that exfiltration
reduced significantly  to approximately 270  GPD;  most of this exfiltration
probably occurred within the manholes.

     Studies  conducted after  the  Insituform was  cured  uncovered  several
visible  artesian  leaks  within  the  manholes displaying the  migration of
ground water along  the main line to these structures.  It would be prudent,
therefore, to include coincident with Insituform sewer lining rehabilitation
of defective manholes, if possible.

FLOW CHARACTERISTICS

     As part of  this study, flow characteristics of  the sewer prior to and
after  lining  were  determined;  Manning's  Roughness Coefficient  (n)  was
calculated  initially   for  the   deteriorated  test  sections,   and  then
recalculated after the sections were rehabilitated to establish the inproved
smoothness of the bore.  The testing procedure utilized the Manning Equation
as defined below:

           0= A l*4fifi Sl/2 R2/3, where
                 n
           Q represents the rate of discharge measured in cubic feet
             per second, a known quantity in this test.

           A is the area of the wetted cross-section of the pipe mea-
             sured in square feet, a measured quantity in this case.

           n is a coefficient which is used as a measure of the
                                     26

-------
             interior surface roughness of a pipe, known as Manning
             Roughness Coefficient, and was determined by this analysis.

           S represents the slope of the energy gradient of the line,
             which in this case was assumed to be the same as the
             slope of the conduit measured in feet of drop per running
             foot of pipe.  Parameters to determine this were measured
             in the field.

           R is the hydraulic radius of the wetted cross-section of
             pipe, arrived at by dividing the wetted cross-sectional
             area of the flow by the wetted perimeter of the pipe.

      Detailed analysis of the before-and-after flow properties of the lines
were  not performed during  this study;  such  determinations are  to  be more
exhaustively  analyzed  under   a   future  program.    For  the  purposes  of
comparison  of   "n",  the   following  method  was  implemented  to  give
representative values for the parameter.

      Prior to  and  after lining  the test  sections, .the  sewage flow was
bypassed  around  the segments.  Known quantities of  water from  the public
water system varying in discharge from 110 to 280  GPM ( .42-1.06 M^/Min. )
were then metered separately by means of a recently-calibrated 2.44 in. (6.2
cm.) hydrant meter  into each test section, and the depth  of  flow measured
with a thin stainless steel  scale at one-minute intervals in the downstream
manhole.   The  flow  introduced into each  segment was  increased half way
through  the test  to determine the effect  on  the  roughness coefficient "n".
The results obtained from the Flow Properties test are displayed in Tables.
Reduction  of the raw  field  data  resulted  in  the  following  values  for
roughness coefficient of each test section both before and after lining:

                   TABLE 6.  MANNING ROX3TOESS COEFFICIENT
Pre-Lining
Stretch
M.H.2-M.H.3
M.H.3-M.H.4
Post-Lining
Stretch
H • u • 2 rl • n • J
M.H.3-M.H.4
Slope %
.253
.270

.253
.270
Test Flow
GPM(M3/Min.)
180 (.68)
250 (.95)
110 (.42)
200 (.75)

160 (.61)
280(1.06)
100 (.38)
280(1.06)
Average Flow
Depth in. (cm.)
3.0(7.62)
3.5(8.89)
3.38(8.85)
3.88(9.85)

2.88(7.32)
3.94(10.00)
2.38(6.05)
3.75(9.53)
- Calculated
"n"
0.0070
0.0066
0.0162
0.1026

0.0077
0.0079
0.0088
0.0081
      The pre-lining values obtained  for  "n'
suspect.   It  is  believed  that the  reduced
 in this analysis appear  very
value  is due  to  significant
                                     27

-------
additional flow contributed  to the M.H. 2 - H.H. 3 segment  through a pulled
pipe  joint  located directly  under a watermain break  (which was discovered
later in  the project) .  Therefore for  comparison,  pre-lining roughness  for
the  in-place  vitrified clay pipe  is  assumed  to  be  "n"  =  0.014.    The
post-lining  *n" is seen to be consistently 0.008-0.009,  reflecting a notably
smoother  condition.   Post-lining  measurements of the  internal diameter of
the rehabilitated  conduit  revealed it  to be  11.30 in.  (28.70 cm) , compared
with  11.626  in.  (29.53  on)   prior  to lining; the  in-place liner thickness
then  is slightly  less than 3/16  in.  (.41  cm).  The reduced cross-sectional
area  of the  sewer coupled with the  added  smoothness increases the capacity
of the  test section from  1.1 MCD  (pre-lined)  to 1.6 MGD  (post-lined), or
some 48 percent.  This increased capacity is corroborated  by statements  from
Village of Northbrook  personnel referencing the absence of any surcharging
events  since  the  rehabilitation  took  place.   This  extremely beneficial
quality of the liner can be anticipated down to and including 8 in.  (20 cm)
diameter sewers; thus, allowing the insertion of a single-layer liner bag in
an  overloaded  sewer  strictly for   the  purposes  of increasing  hydraulic
capacity.

                INSITOFORM LINER
Bypass Requirements

      Prior to actual  installation of the Insituform liner, provisions must
be  made to  overpump  the upstream  flow  around  the  segment.   The actual
bypassing  setup   is  of  great  importance  to  the success  of  the lining
operation  and  requires  proper  planning  to  assure   its adequacy.   When
planning the  overpumping  care must  be taken  so that placement of plugs,
suction line, discharge line and pumps does not interfere with the inversion
of the liner.

     Considerations to be taken in the planning  of the bypassing operation
include the size  of the  existing manholes as well as the size and length of
the  sewer  being  lined and its  wet weather daily  average and  peak flows.
Larger  diameter  sewers  require  larger  diameter  inversion  tubes  in the
inversion manhole,  and thus available  space for workmen,  discharge lines,
and suction lines become  critical.  In many cases it is advisable to bypass
from one manhole  upstream of the  inversion  manhole to one manhole past the
end  of the section being  lined.  Bypass pumping  should be  scheduled for
twenty-four hours continuous  duty from  the start  of the operation,  with
back-up equipment available for periods of maintenance and  refueling.   The
actual length of  overpumping will depend  on factors such as length and size
of line, number of  services, normal flow in the line, the physical location
of the section, and the relative ease with which the operation proceeds.

     In most cases, the bypassing of services  would not be  required as it
was  in this  research project.   The reason  for  this  is that,  unlike the
demonstration,  the  installation  of the  liner is  generally  made  at night
during periods of limited sewer use by the customers.   The user  is informed
well  in advance  of the installation  date that his water service  will be
turned  off  for up to  twelve  hours.  Minimal  usage of water  should not be
allowed since  this  wastewater  tends to collect on  the outside of the liner

                                     28

-------
at the service  tapf  and during cutting  operations to reconnect the service
this water  and  debris splashes on the camera  lens,  signficantly  iirpairing
the view and slowing the reconnection procedure.

     If the service cannot be limited or turned off for this amount of time,
then bypassing  of  the service will be  required.   In many cases this can be
accomplished  by constructing  a  snail  sump  between  the building  and  the
sewer.   The  downstream  side  of the  sump  is  plugged  and   a pump  with
appropriate hose  is installed.   The  discharge point  for the  flow from the
sewer service would  normally be  the same  as  that for the sewer line being
bypassed, unless some provision can be made for an intermediate connection.

     A  very  sophisticated  bypassing  system was developed  for  the  test
section  in Northbrook.   It had  been determined  in advance  of the actual
Insituform  installation that because of the tests  to be  run before  and after
the  installation,  and  the  number of  spectators   involved,  that the bypass
should be operated for a period of several days.

     With  this  in mind, a bypassing  system was set up  using  6 in. (15 cm)
diameter  ABS rigid  pipe  with the  joints solvent welded.   The  pipe  was
installed some  20 ft  (6 m) west of the existing sewer, and anchored in place
on the  surface  by rebars driven  on  either side of the  pipe.   The pipe was
then wired to the rebars.  Three driveways  (which had to remain open) were
crossed with  overpumping pipe, sc that  it was necessary  to provide crushed
stone  ramps over the  pipe in these  locations  and maintain these  crossings
for one week.   The bypassing system is  shown  in Figure 6.

     The two services were handled by the  construction of sumps on  the 6 in.
(15  cm)  service  lines and  the  installation of  one 2  in.  (5  cm)  diameter
electric  submersible  pump  and  one  portable  gasoline  power  pump.   The
discharge   from the  punps was  directly  connected to   the 6  in.  (15 cm)
diameter  rigid bypass line by  means  of  a  solvent-weld wye   and  necessary
bushings.   One  of the service bypass  systems  is shown  in Figure 7.

     Sewer services   can  be  handled  by  bypass,  plugging   or   limiting
discharge.  The hydrostatic pressure caused by the presence of waste in the
sewer system must never be allowed to be greater  than  the inversion head.

     The  total  bypass line extended over 1000 ft  (305 m) in length starting
from one manhole  upstream of the  two  proposed lining  sections  to one manhole
downstream.  The original plan called for discharge of  the  overpunping flow
to  be  at  the  aid  of  the  lining  sections,  but  this  discharge caused
turbulence which interfered with  ongoing tests.
                                      29

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Figure 6. Six-Inch Diameter ABS Rigid Pipe Bypassing System
Figure 7. Service bypass sytem with portable gasoline power pump,






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            Cleaning and Internal Inspection

     Preparatory cleaning  and internal inspection were  also performed just
prior to the  installation  of the Insituform liner.  This phase  is essential
as the Insituform  liner  bag is inverted into the line and not simply pulled
into place.   This  inversion process causes  the bag to unfold from within
meaning there is  no relative movement  between  the surfaces of  the bag and
the pipe being lined after  they make initial contact.  This lack of movement
between the  liner  bag  and  the  pipe wall  results  in encapsulation  of any
material deposits  which  remain in the  sewer  during  inversion.  In addition
to the loss in cross-sectional areas due to the  encapsulated materials there
is  also a  severe  loss  of  structural  strength.  A  flat area in  the bag
equivalent to one-quarter  the diameter caused by a  pipe not being properly
cleaned can  reduce the  structural,  load carrying  capacity by  40 percent;
thus, the  requirement for  preparatory cleaning and internal inspection just
prior to installation of the Insituform liner.   Additionally, the television
inspection  will  detect  any protrusions  within  the conduit  due  to poor
service taps, broken pipe,  etc.,  which might  act  to  puncture  the liner
rendering it  impossible to  cure.

              Euiment and  Materials
     The  basic  items  of  equipment  and  material  required  for  a  typical
 Insituform  installation and a brief description of each is  as follows:

     The   inversion  platform   consists  of   construction-type   sectional
 scaffolding erected over  the  point  of  inversion.  The inversion platform
 supports  the  inversion tube,  workmen,  liner bag, and recirculation  hose
 during  the  inversion phase of the installation.  The height of  the platform
 depends on  the required inversion head and depth  of sewer  to be lined.   The
 inversion head requirement will be discussed  in more detail in the  section
 on  liner  insertion,  later  in this  report.

     The  inversion  tube  consists  of  a  reinforced  polyester  tube  of
 sufficient  diameter and length to allow the liner bag  to pass  from  the top
 of  the  inversion platform to a  steel  inversion shoe located in the invert of
 the sewer to be lined.  The top of the inversion  tube  is attached to  a steel
 ring.   This steel ring  supports  the  inversion  tube  which  hangs from the
 inversion platform on cross-members of the scaffolding.

     The  inversion  shoe   is a  prefabricated  90  degree steel  elbow of the
 appropriate diameter for  the sewer being  lined and the inversion tube being
 used.   The  inversion shoe is attached  to the bottom  end  of the  inversion
 tube by stainless steel straps. The  Insituform liner  bag is attached to the
 other  end of the inversion shoe also by stainless steel straps.  The method
 of  attaching the liner  bag will be discussed in detail later in  this  report.

     The  portable mixer  is  a drum type mixer used to mix the appropriate
 catalyst  with  the  non-promoted resin just  prior to transferring  the  resin
 from the  shipping barrels into  the Insituform liner bag.

     A transfer pump is  the  pump used  to transfer the catalyzed resin  from

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the shipping  barrels  into  the liner  bag for complete impregnation of the
felt.

     The vacuum pump is  a pump used to evacuate the air  from the  Insituform
liner bag  prior  to  introducing the  resin into the  bag.   It enhances the
drawing of  the resin into the  felt.   The requirement  for  a partial vacuum
within the  bag during this  process emphasizes the  need for  a polyurethane
bag-covering which is entirely  free of pinholes.

     The wet  down conveyor  system is  a  three-level  conveyor  system  through
which the Insituform liner  and resin are passed to insure  even distribution
of the resin  material throughout the  entire  bag length.  Doctor  or  squeeze
rollers are used  at  the  top end of the conveyor to  insure the proper  resin
saturation of  the bag material  throughout.

     The lay-flat hose is a high-pressure hose  used to  circulate hot  water
to the far  end of the liner bag during the curing process.   It must  be able
to  withstand  the  very  high  temperature  at  which  the  water   is  being
recirculated.

     The hold back  rope is a  rope used  to  control the rate of inversion
after the  bag is half way  inverted.   If the liner inverts  too swiftly, the
water head may be lost  in  the inversion tube creating  air pockets in the
liner.  The rope is attached to  the  end of the bag  away from the point  of
inversion by  means of tape  and wire.  It is also used  to help hold back the
far end of  the bag when  it arrives at  the desired end of  the inversion  run.

     The water supply line is the line used to  supply  the water to the
inversion  tube.   In  most situations this hose is connected  to a nearby fire
hydrant.

     The water control valve is a valve located at the top of the inversion
platform.   It  is used  to  control  the  height  of  the  inversion head and
thereby the rate  of  inversion.  It  is  extremely  iaportant that the inversion
head be maintained at a  static  level throughout  inversion.

     The circulating pump is  a pump used to circulate  the water from the
inversion  tube to the heat exchanger  and then through the  lay-flat  hose  to
the far end of the sewer section being relined.

     The boiler and heat exchanger  is the source of heat  used for bringing
the water  used in the inversion process up to the curing temperature of the
thermosetting resin.

     The   Insitucutter  is   a  patented  device  which  allows  the   remote
reinstating of  existing services  by means  of  a cutter  which  is pulled
through the relined  sewer in tandem with an  internal  inspection camera. The
device   is   positioned   and   controlled  by  an   operator  utilizing   a
three-dimensional control system  to cut  out lining material in the  areas
identified as service taps  from the picture  on a television monitor. The
television monitor  shows a picture  received from  the  internal  inspection
camera which  is located  on  a sled.

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     Thermocouples ace temperature sensing devices placed between the  liner
material  and the sewer  wall to  read the  temperature during  the  cure  and
post-cure periods.  They give accurate indications of  the cure-status of  the
material.

     The  liner  bag  is made  from  polyurethane-coated,  polyester-fiber  felt.
It  is  made of  densely  needled polyester  fiber,  and  can vary in thickness
from 1/8 to  3/4 in. (3  to 18 ran)  in  the prelining  state.   The  liner  is
usually made of multiple layers of fiber of 1/8  in. (3 mm)  each  to give  the
desired  total thickness.  The primary function  of the felt is to  act as  a
medium to hold the resin prior to curing.  Each  layer is  individually sewn
into a  long  cylindrical tube  of  the  proper length  and  diameter  for  the
proposed  lining application.  Liners can be custom-designed and  constructed
for perfect  fit.  A polyurethane  film is applied to the outer  surface of  the
outer  layer  of material  only.   Its purpose  is  to  provide  an air-tight
membrane to  enable a  vacuum to be drawn  on the bag during resin impregnation
and to allow the circulation of curing water throughout the liner as well as
providing a  smooth flow  surface for the  inverting process.

     The polyester resin  is a thermosetting resin used to impregnate  the
polyester fiber felt   liner.    This material   forms the  actual   smooth,
resistant structure  within  the   original conduit.   The  resin  is  of  the
isophthalic-acid-based-polyester  thermosetting  type and  is  shipped to  the
job site non-catalyzed.  The resin may  contain certain  additives to obtain
special  characteristics  required  for each application.

     A catalyst is the chemical compound  such as percadox  which  is  added to
the resin to initiate  the  reactive  properties  of the resin,  to assist in
determining  the curing  temperature, life and hardness  of  the product.   After
the catalyst is added  to the  resin, the  resin  is considered to be in  the
promoted, or reactive state.

Installation Procedure

     The  Insituform  installation  team  consisted of  thirteen  (13)  men as
follows:  One  general  foreman,  one 3-man preparatory  cleaning crew,  one
2-man  crew for internal inspection and evaluation, one 4-man crew to install
and cure the  liner  and one  3-man  crew  to cut or  reinstate  the  service
laterals.

      in  addition  the Insituform  installation  team is assisted  by a  3-man
crew  located at the wet out  area.  This  3-man  crew  can  serve  up  to three
 installation teams.

      The  general  foreman  is   responsible for  coordinating  the  entire
 installation from initial preparatory cleaning to final  inspection and clean
 up.  The  foreman may assign additional  manpower as required to  keep work on
 schedule.

      The  3-flian preparatory cleaning crew performs  all necessary efforts to
 prepare  the sewer for  lining.   This may require  root  removal, bucketing,

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swabbing or high pressure jetting.

     After  the  preparatory  cleaning   is  completed  the  2-tnan   internal
inspection and evaluation team  makes an inspection of the line to ascertain
that the cleaning is complete and also to  record on a TV log the  location  of
all line  deficiencies and service  connections.  In addition  to the TV log
the line is video taped.

     As  soon as  the  internal  inspection  crew  completes  their work and
evaluates  that  the  line is  ready  for  lining the 4-nan  installation crew
starts erecting  the inversion  platform.   This crew is  responsible for the
actual inversion and curing of  the liner as  detailed on the following pages.

     After the  liner is installed,  cured and  cooled  down the services are
reinstated by a 3-tnan crew  using the Insitucutter.  This crew also  performs
a  post-Insituform  internal  inspection  including  the  video taping of the
Insituformed liner.

     The  Insituform  installation  team  is  supported  with  the following
equipment:  sewer  cleaning  equipment, i.e.  high pressure  watei  jet, bucket
machines,  a  twenty-six foot  truck  equipped with  boiler/heat  exchanger and
circulating  pump,  a  twenty-six  foot  materials  truck  and  an   internal
inspection van.

     The  wet out  crew  is  equipped with  a semitrailer truck containing  a
three tiered conveyor system and appurtenances for mixing and transferring
the  resin to  the  liner bag  for   felt  saturation.   In  addition  to the
semitrailer truck the wet out crew has tarps used  to make sun shades so that
all resin handling can be performed  out of direct sunlight.

     If  the  pre-Insituform  internal  inspection  indicates  the sewer   is
sufficiently  clean  and  free  of  protruding  services the  actual lining
procedure can begin.

     One  of the  first  steps  in  the  Insituform  lining  technique  is the
erection of the inversion platform.  This  platform is erected over the  point
of inversion of the liner into  the sewer usually a manhole.

     The platform  is constructed of structural steel  tubing using  standard
scaffold frames and accessories.  The scaffold height varies with the  depth
below  grade and  the  diameter  of  the  sewer   being  lined as  well  as the
thickness  of  the liner.  The inversion  heads  may vary from a maximum  of  38
ft  (11.5 m) on  a 6 mm thick, 8 in.  (20 cm)  diameter  bag to as little  as  12
ft  (3.6  m) on a  9 mm  thick  24 in.  (60  cm) diameter bag.  The larger the
diameter,  the  smaller the  head needed for  the inversion.  Five  to six  ft
 (1.5 m - 1.8 m)  below the top  of the scaffold, a  walk platform  is installed
for  the  workmen to stand on during the  inversion.   Eighteen  in.  (46 cm)
below the  top of the scaffolding an  adjustable inversion tube  support system
is  installed.   This support system  sustains the  steel rings  at the top  of
the inversion tube.  At the very top of the  scaffold a capstan is positioned
to act as  a pulley for  the bag  line  or hold  back rope.


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     Care must  be taken when erecting  the inversion platform to assure  the
feet of the  scaffold  legs are on good firm ground  and that the scaffold  is
level  in  all directions.  Some  minimal excavation  or footing construction
may be necessary to provide the desired degree of safety.

     At the same tine the  inversion platform is being  erected, the  liner  bag
is being  prepared for  insertion.   There are several  steps to be  taken  in
this preparation phase.   One  of  the first and ongoing procedures throughout
the entire installation is the visual inspection of the bag for any obvious
flaws such as pin-holes or tears in the polyurethane coating.  These defects
may have  been caused in manufacturing  the bag,  although flaws of  this type
would  have most likely been detected earlier during quality-control by  the
manufacturer.   Faults also may have occurred as a result of shipping or  job
site  handling.   If there is a  defect  in  the  liner,  it is  much better  to
detect it before  the liner is installed  in the sewer than to realize that
the recirculating water is leaking.

     After the  liner  is unpacked from its shipping container, a vaccum pump
is attached  to the bag to evacuate the  entrapped air  from the felt-liner
material.  This,  in itself, gives a test as  to the soundness  of the liner
since  in  a damaged bag, it would be impossible to draw and  maintain a vacuum
within the system.

     While the  air is  being  evacuated  from the  liner,  the  resin  is being
prepared  by  other workmen.  As  mentioned earlier,  the  resin is shipped  to
the job  site unpromoted  in  drums.  The  resin  is stored in the unpronoted
state  until  just prior to use.   It is  much more stable  and  has  a longer
shelf  life in the non-promoted condition.

     Resin is generally shipped to the project site  in removable lid type
drums  in  order  to facilitate mixing and transfer.  The lids are removed from
the  drums  and  the  prescribed  amounts  of  catalysts  are  added  and   the
ingredients  thoroughly  mixed with  portable flash-type mixers.  The lids  are
then  replaced on the drums  to await transfer  of the resin  into the liner
bag.   Care  should  be  taken  to  keep  the  resin  material  away  from direct
exposure  to  sunlight; ultra-violet rays tend to deteriorate the composition
of the material.   Prolonged exposure  in the presence of heat can possibly
cause  a the mo-setting  reaction.   The resin may be kept  in  this state for  up
to forty-eight  (48)  hours providing it  is out  of direct sunlight  and below
40°F  (4°C).

The quantity of resin used for  each  installation should be equal by volume
to  110 to  115 percent of  the volume of  felt in the liner  bag.   Resin
material  must be liberally-spread throughout  the liner  bag,  replacing  all
the air in the  Insituform. Many times  the activated resin  contains a dye so
that  the  spread of material throughout  the bag can be  documented.  An  air
pocket in the liner, devoid of resin will not cure and therefore a  soft spot
in the finished product will result.

     The  quantity  and  type  of  catalyst  are  determined  based  upon   the
proposed  curing  conditions  as  well as  the recommendations  of  the resin
manufacturer.

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When the desired  level  of vacuum (5 to 8 pounds per square inch)  is  reached
on the  liner bag  it  is ready to  receive the catalyzed  or  promoted  resin.
The transfer of resin to the liner is accomplished by the use of a hydraulic
transfer pump.  The pump  suction is placed in each drum  and the contents of
the drum are pumped to  the line opposite the end of the  liner to which the
vacuum pump is attached.   After  all the promoted resin has been transferred
to the liner, the bag is resealed at the ends.

     The next step in the preparation of the liner bag is the saturation of
the  liner felt.   An even and  thorough  saturation  of  the liner  is very
important to assure uniform strength and cure of the line when in  place.  To
assure the even distribution  of  resin throughout the line it is passed over
a  three level conveyor system.   This variable  speed system  delivers the
liner bag to the squeeze rollers  at the proper  speed  to  assure complete
saturation of  the felt liner.   The doctor rolls  are  preset at  the  proper
thickness to  allow just  the  right amount of  resin to pass to assure even
distribution throughout the length of the liner.  The process of  saturating
the liner felt with resin  is referred to as "Wet Out*.

     For  reasons  previously stated, the saturated  liner  should be kept out
of direct sunlight and  at or below 40° F (4°C)  during  transportation and
storage.  The "Wet Out"   should  not occur  in excess of twenty-four hours
before the estimated installation time.

     In most  cases the wet down area is located within  a few  miles of the
installation  site.   However,  in  the  case  of  Northbrook  this was  not
feasible.  Based  upon recoonendations from Insituform Limited, Northampton,
England,  Insituform East  of Hyattsville, Maryland, was selected  to  install
the  test  section  in  Northbrook.   After   several   communications  with
Insituform East it was determined that it was not practical to transport the
entire  wet  down  system over  1600 miles  (2575 kilometers)  round  trip  to
process the 585 L.F.  (175 m)  of 12 in.  (30 on) diameter  bag needed for the
Northbrook project.

     An alternative plan was developed  to have only  the installation crew
mobilized from Hyattsville to Northbrook for the liner insertion.  After the
crew  arrived  in  Northbrook   and  made   their   pre-Insituform  internal
inspection,  finding everything  in  order,  they were  to alert   Insituform
headquarters  in  Hyattsville.  The bag  would at  that time be wet  out  in
Hyattsville and  sent non-stop to  the project site via  refrigerated  truck;
the  trip  was estimated to take approximately sixteen hours.   All items of
the wet out were to be the same as a normal processing procedure.

     The Insituform East installation crew arrived in Northbrook,  Illinois  ,
Sunday night, September 30, 1979.  Early the next morning, the test site was
inspected by  Insituform East internal  investigation  personnel, accompanied
by the  Village of Northbrook Public Works  employees along with personnel
from  the  firm of Driver,  Olson and  DeGraff, Village  engineers  for this
project.  During  this  inspection  the overpumping  arrangement was reviewed
and bypassing requirements were discussed.


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      The  overpuroping  was  started  by  a  local  contractor,   and   initial
 preparatory cleaning was performed by the Village of Northbrook Public Works
 Department  forces  using  a  high-pressure  water  jet.   Figure  8  shows  the
 cleaning  operation.    Immediately  following  the  preparatory  cleaning/
 Insituform East personnel performed  internal inspection of  the  line with
 closed circuit television to  verify  line  condition and length.  With this
 verification completed, the wet down order was relayed to the home office.

      Following the  internal  inspection  and with  the  flow  still being
 bypassed,   personnel   of   the   Engineer  performed   infiltration  and  flow
 characteristics tests  as previously described in this report.  After  a final
 cleaning exercise, the test section would be ready for rehabilitation.

      The  Village   of   Northbrook  personnel   again   performed preparatory
 cleaning  to remove gravel  that  was noted  during the  previous internal
 inspection.  Again the line was  televised to ascertain the results of  the
 latest  preparatory  cleaning  by  the Village personnel.   The  inspection
 revealed  the  sewer now  to be adequately  cleaned so  chat  lining could
 proceed.
Figure 8.   Village of Northbrook  Public Works Department perform-
             ing  pre-Insituform cleaning   with high-velocity water jet
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    Although the actual lining and overpumping equipment was  located  off  the
pavement and  on the right-of-way, it was  decided to block off one lane  of
traffic of  the 4-lane highway.  This traffic control was done only  for  the
safety  of  the  observers.   It was  not  actually  necessitated by the  lining
operation.  The appropriate signing and  traffic control  was installed  and
handled by the Village of Northbrook Public Works Department.

     The erection  crew began setting up the  inversion platform as soon  as
the cleaning and inspection personnel were clear of the work  area.  A 20 ft
(6 m) static head  was  to be used to invert the 1/4  in. (6 mm), two-ply,  12
in.  (30 on) diameter liner.  The sewer  invert at the point of inversion was
approximately  9 ft (2.75 m)  below ground  level  and therefore an inversion
platform height of  11 ft  (3.3  m) was  used to  give  the desired inversion
head.

     After  the scaffolding was  erected,  the inversion  tube  support  system
was  installed  to  anchor the steel  rings  on the upper  end of the inversion
tube.  Next the inversion tube complete with upper steel  ring and inversion
shoe was put  into  position (Figure 9).   The lower end  of  the  inversion tube
with  shoe was  carefuly  lowered into  the manhole  to check  its  position
(Figure 10).

     The bottom of each leg on the scaffold is equipped with a screw  jack  to
level  and  adjust  the  height  of the inversion  platform.   This adjustment
permitted the  exact positioning of  the steel shoe  in such a way  that  the
liner  bag would   report  out  in line  with  the  sewer.   Total length   of
inversion from start  to finish was 585  L.F.  (175 m).  The installation was
made in two separate inversions.  The first inversion from Manhole No. 2  to
Manhole No.  3  was 150  ft  (45  m)  in  length.   The second  inversion from
Manhole No.  3 to  Manhole  No.  4 was 435  ft  (130 m).   Both inversions were
made with the flow.

     Under normal  conditions the entire 585 ft (175 m) stretch between MH 2
and MH 4 would have been inverted  at one time with one setup.  However, two
separate inversions were made in Northbrook to facilitate  the  large group  of
observers in  attendance.   Inversion can be made  either with or against the
slope of the  rehabilitated sewer,  but detailed consideration must be given
to changes in the grade of the sewer being lined when determining maximum  or
minimum head  that  the liner bag  will  be subject  to. Inversion  from the
middle manhole  of  the  test section could have been planned in Northbrook  to
eliminate  moving  and  re-erecting  the  inversion platform,  but again two
complete inversions were deemed advisable so  that  spectators  not  able  to
attend the first day of inversion would not miss  the demonstration entirely.

     Water  for  use  in  the  inversion was   supplied  by the  Village   of
Northbrook from a  hydrant located approximately  120 ft (36 m) south of the
inversion platform for Manhole No.  2 and 30 ft (9m) north of the inversion
platform for Manhole No. 3.

     A conventional fire hose was  used to supply the water  from  the fire
hydrant to  the top of the  inversion platform.   The  end of the  hose  at the
top of the inversion platform was  equipped with a gate valve  to control the

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Figure 9.  Inversion tube complete with upper steel support ring
           and inversion shoe being raised into place on the in-
           version scaffold.
                               39

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Figure 10.  Inversion tube and shoe being positioned in manhole




                               40

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water supply rate in order to maintain a constant head  (Figure 11).

     After the  inversion platform, inversion tube, and supply hose were in
place,  the crew  was  ready  for the  liner bag.   The  wetted-out  liner bag
arrived from Hyattsville,  Maryland, in a  refrigerated  truck,  the bag being
laid fire hose style in the controlled environment.  Upon reaching the site,
one  end of  the  bag  was  immediately cut off  and folded  over to  make a
triangular point  and  taped with  duct tape, in  order to facilitate passing
the  bag through  the  inversion tube.  The 12 in.  (30 cm)  diameter bag is
shipped flat and  therefore is about 19 in. (48 cm) wide.  TO pass the liner
bag  through  the  inversion tube during  insertion it must  be folded  as it
comes off the truck by the installation crew.

     Prior to  inserting the end of  the  liner bag  into the inversion tube,
the  portion of inversion  tube and  inversion  shoe  previously  within the
inversion manhole were removed  to  an above ground position to facilitate the
attaching  of  the liner  bag  to the  inversion  shoe.  The liner  bag  end was
next passed over  a roller conveyor to the top of the inversion platform and
down the inversion tube until about 6 in. (15 cm)  of the pointed end of the
liner bag  extended out of the  inversion shoe. The liner  bag however still
was  not in position to be attached to the inversion  shoe—to clarify, the
bag  was shipped with the polyurethane coating on the  outside  and when the
liner bag  is  inverted into the sewer,  the polyurethane coating becomes the
inside  of  the liner bag.  As  the word inversion implies,  the  liner bag is
turned  inside  out  during  the  installation  of  the  liner   (Figure   12).
Consequently,  the duct tape was  removed  from the pointed end and the outer
layer of polyurethane covered felt was folded back over the inversion tube.
Next,  a  piece  of stainless  steel  banding  was  tightened  over  the  bag
material,  firmly  attaching it to the inversion shoe  (Figure 13).  The under
layer of felt  was then folded back over the shoe and firmly anchored to the
shoe—the  system  used  in Northbrook was  comprised of two felt layers  (Figure
15-1).

     The proper banding of the liner  bag to the inversion  shoe is critical
to the  work, as should the bag come loose from the  shoe or  a leak  develop at
the  interface, the inversion would  have to be stopped because curing could
not  proceed.    If the problem could  not be corrected quickly, the entire
insertion  might have to be scrapped.   This most likely would result in the
loss of the liner bag,  resin  and  all preparatory work.

     After it  was established that the liner bag had been  properly  attached
to  the inversion shoe,  the  inversion  tube  and inversion  shoe were again
lowered into position in the  manhole for inversion, and wood thrust  blocking
to brace the shoe was installed (Figure  14 and Figure 15-2).

     The water was then turned on, and the inversion tube  was  slowly filled
to  the desired inversion  head as recommended by the bag supplier  (20 ft  [6
ml  in this case).  The  bag  is restrained until the  head  is reached by the
workmen on the inversion  platform and in the truck  (Figure 16).  The  liner
bag  was then allowed  to slowly report out of  the inversion shoe and  into the
sewer  itself.  As it slowly  entered the  sewer,  a thermocouple was placed
between the liner  bag and the sewer  pipe to measure  temperatures in  this

                                      41

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*-
ro
    Figure 11. Village of Northbrook hydrant
               and fire hose used to supply
               water for the inversion.
Figure 12. Duct taped end of liner bag
           extending out of inversion
           elbow.

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Figure 13.  Stainless  steel band being
           tightened  on the outer
           layer  or first layer of
           the  liner  bag.
Figure 14 .  Preparing to lower inversion
           shoe with properly banded
           liner bag into inversion
           manhole.

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  THE LINING MATERIAL IS THREADED
  DOWN THE INVERSION BAG.
    INVERSION BAG —
  POLYURETHENE 	
  MEMBRANE
LINING MATERIAL

 MANHOLE WALL
  STEEL 1/4 BEND
 PIPE TO BE LINED
      THE END OF THE LINING MATERIAL IS
      OPENED UP, TURNED INSIDE OUT AND
      CLAMPED ONTO THE STEEL 1/4 BEND.
        WOOD BRACING
  STAINLESS	
  STEEL CLAMPS
   WATER IS PUMPED INTO THE INVERSION
   BAG AND AS THE WATER PRESSURE BUILDS
   UP, THE LINING MATERIAL STARTS TO
    TURN INSIDE OUT INTO THE PIPE TO BE
    LINED.
 4
AS THE END OF THE LINING MATERIAL
DISAPPEARS INTO THE INVERSION BAG,
LAYFLAT HOSE IS ATTACHED TO ITS END,
THIS HOSE IS PULLED RIGHT THROUGH
THE PIPE', AND IS USED TO CIRCULATE
HOT WATER.
                                      WATER
                                               LAYFLAT HOSE
                       l
   WHEN THE LINING IS FULLY CURED THE
   DOWNSTREAM END OF THE BAG IS
   PIERCED TO ALLOW THE HOT
   CIRCULATING WATER TO DRAIN.
  PIERCE IN DOWNSTREAM
   MANHOLE
     THE ENDS OF THE LINING MATERIAL ARE
     CUT OFF TWO INCHES BEYOND THE END OF
     THE PIPE THE PIPE IS AIR TESTED USING
     AN EXPANDING STOPPER DEVELOPED FOR
   THE PURPOSE, THE SECTION OF PIPE
   WHICH WAS REMOVED IS TRIMMED TO THE
   CORRECT LENGTH AND JOINED INTO THE
   THE PIPE USING A RESIN, FELT AND
   GLASS FIBRE BANDAGE.
             It
                                                     DOWNSTREAM M.H.
                        II I
                        'I i
              11
              11
              11
                    FIGURE
STEPS IN LINING WITH INSITUFORM
                                    44

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Figure 16.
Workman on right turns on water supply valve as
workman on left restrains liner bag until inversion
head is reached.
                               45

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critical  location  (Figure  17);  this  unit was  held in position by static
water pressure.   Proper alignment of  the liner bag  into the  sewer  at the
start of  the  inversion was checked very closely by the installation crew
(Figure 15-3).

     The supply valve  on the water line is carefully controlled  to maintain
the hydraulic head as the liner was allowed to slowly  report  out into the
sewer.  This  process continued until the  end  of the liner bag in the truck
was within approximately 10  ft (3  m)  of the top of  the inversion tube.  At
this point the inversion was halted.   The liner was now half  way into the
sewer being lined.

     A hold back  rope  was then wrapped around the capstan at the top of the
platform and  attached to the end  of the liner bag.  This  rope was  used to
control the rate of inversion by holding back  the liner bag.  Should the bag
be allowed to proceed  unimpeded, it would  very possibly  report  out at such a
high  speed   that   a   constant  water  head   could  not   be   maintained.
Simultaneously with the connection of  the hold back rope,  a  lay-flat hose
was also attached  to the end of the liner  bag.   The purpose for the lay-flat
hose  is to  carry the  heated water from the heat exchanger unit to  the far
end of the liner bag during the curing  process (Figure 18 and Figure 15-4).

     It 'has  been  found  that a  more  even cure  rate  can  be  obtained  by
allowing  a portion of  the  heated water  to  be released along  the entire
length of the lay-flat hose.  This is  done by providing orifices along the
length of the lay-flat hose.

      After the lay-flat hose and hold  back  rope were secured to the bag end,
 the  inversion  continued.   As  the  liner bag  approached  the downstream
 manhole,  a  second   thermocouple  was   placed  between the  liner bag and the
 sewer pipe wall.

     Prior  to the inversion  process starting,  a frame  back-stop  was
installed in  the far manhole to assure the stopping position  of the liner
bag.  The liner bag is  normally allowed to enter 6-15  in.  (15-30 cm)  into
the  far  manhole before the  inversion  is  terminated.   This projection into
the manhole allows the liner bag to expand and  cause a  slight  flared end at
the sewer-wall intersection  producing  a superior seal between  the sewer and
the liner.   After the  inversion has been completed, the hold  back  rope is
tied  to the  capstan at the top of the  inversion platform in order to secure
the bag in place.

     With  the liner bag completely  inverted,  the  next procedure  was the
curing of the thermosetting  resin-saturated liner bag.  The  curing of the
liner bag is  accomplished by heating the water  used  to  invert  the liner bag
to  a  temperature  which will  cause  the  resin to  cure and  harden.   The
temperature  needed  to  cure  the liner  bag can be adjusted by  the type and
amount  of catalyst added to the  resin before  wet-out.   In Nbrthbrook the
normal cure temperature of 180°F  (82°C) was used.
                                      46

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Figure 17.
Looking at the liner bag inverting in sewer.  At
9 o'clock position, note wires from thermocouple
placed in sewer between sewer pipe and liner.

                   47

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 Figure 18.  Top right shows rope wrapped around capstan and
            attached to end of liner bag.  Lower left shows
            lay-flat hose used to circulate heated water from
            boiler/heat exchanger.
    The heat exchanger  and recirculation pump were mounted in a truck which
was  backed up  to  the  inversion  platform  (Figure 19).   This truck  also
contained a diesel-driven generator to power the electric drive motor on the
recirculating pump,  and to supply electricity  for  other  lighting  and power
requirements.   In  addition  to  the  generator,   the  truck  contained  an
oil-fired  water tube  boiler  to supply  heat  for  the  heat  exchanger.   A
suction line was attached from the inversion tube to the recirculating pump.
A second hose attached  the heat exchanger to the lay-flat hose.  A complete
recirculation loop was now in place  taking water from  the inversion tube
through the heat exchanger  and returning  it back into the sewer line via the
lay flat hose.
                                      48

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Figure 19. Back of truck showing recirculation pump.
     After  circulation  was  begun and  it  was  determined  that  the  flow
distribution was proper, the  boiler was  fired and the heat up began.  Water
temperature at  the  beginning  of the heat-up  was 55 °F  (12 °C).  Temperature
gauges  on the  suction and discharge  lines  in the  truck snowed  that the
temperature of the circulated water increased rapidly as it went through the
heat exchanger and into the liner section.

     Monitoring of the thermocouple temperature at the near and far manholes
showed  the  actual  increase in the  temperature  of the liner  bag.   The heat
sink  ability  of the ground  around a sewer  can  vary greatly  with ground
water, backfill and  local  utility  conditions, and therefore the temperature
of recirculating water versus liner bag  outer surface temperature may vary.
Hence, the temperature of  the circulating  water should never be used as the
only criteria for determining the extent to which the process has proceeded.

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     The curing  of  the  liner in the 150 ft (45 m)  inversion from Manhole No.
2 to Manhole No.  3  was  as  follows.   The initial heat up period from 55 F°(13°
C)  to  160*F  (71°C) took  45 minutes.  During  this portion of  the  cure the
resin  went from  a  liquid  to a gel  state.   The corresponding  thermocouple
reading was raised to  110 °F  (43°C).  Near the end of the initial heat up
period of  45 minutes an exothermic reaction occurred  in  the resin and the
thermocouple  reading  advanced to 145°F (60°C), sufficient for  the  liner to
harden.  The boiler/heat exchanger unit continued to heat the recirculating
water from 160°F (71°C) to 185°F  (85°C).  This operation  took approximately
an  additional  30 minutes while the bag continued to cure.   At 185°F  (85°C)
the bag entered  the post-cure period  which lasted two hours,  the boiler/heat
exchanger  cycling  on  and  off in  order to  maintain  the  185 °F  (85 °C)
temperature  in the circulating water.  A full two hour  post-cure insures
that the  liner will  nave  the highest  structural  qualities achievable  from
the particular resin and  felt  system  used.  At  the end of  the post-cure
period a hole  1  1/2 in. (3.8 cm) in  diameter was pierced  in the end of the
bag by means of a  long steel rod.  As the hot water drained slowly out  of
the bag,  cool water  was  introduced  at  the  inversion tube  to maintain  the
inversion  head.   The  recirculating pumps  continued  to operate through  this
cycle.  This  caused the liner bag to  go  through a uniform and controlled
cool down  phase.  The cool down period lasted for one hour and  reduced the
temperature of the  circulating water to 100°F (37°C).  The controlled  cool
down period is utilized to prevent  thermal shock and to  control  shrinkage of
the polyester  material.  The  total time from  heat up to  cool down for  the
150 L.F. (45 m) section was four hours and fifteen minutes.

     The respective times for  the  inversion from Manhole No. 3 to Manhole
No. 4  ( 435 L.F. [130 ml)  were as  follows:  Initial heat  up of 55°F (13°C>
to  160°F  (71°C)  to 185°F  (85°C) was  45  minutes; the post  cure at 185°F (85°
C)  was two hours; the cool down  period  from 185°F  (85°C) to 100°F (37°C) was
one hour 30 minutes.  Total time from heat up to cool down for  the  435  L.F.
(130 m) section was five hours 30 minutes.

     As  a  safety  measure,  no  one  was   allowed  in' any  of  the  manholes
downstream of the  inversion  site  while  the  temperature  in  the liner was
above 100°F  (37°C)  (Figure 15-5).

     When  the  tenperature  reached 100°F  (37^0  the end of the  liner bag  away
from the inversion  manhole was  cut open and the inversion water allowed  to
run out.   The ends were then severed at the point of intersection with the
manhole walls  by using  a small diameter, pneumatically-operated,  right-angle
power saw  (Figure 20).   Edges of  the liner  bag were then thoroughly sealed
at  the manhole  wall  with  a  special  mixture of  resin and  sand  giving a
completed  and finished look to  the  lining,  as  well as  to  prevent any
migrating  clear water from entering the manhole.  While the ends of the bag
were being  cut  out  and  sealed  the cleanup    crew  was dismantling   the
inversion  platform  and performing general  cleanup  (Figure 15-6).

     On the second  inversion from  Manhole No.  3 to Manhole No. 4 the liner
was 8 in.  (20  cm)  short of reporting into the manhole.  This did not affect
the overall success of  the lining installation as there was no damage in the
8 in. (20  cm)  between the end of the  liner and the manhole.  If  required the

                                      50

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installer was prepared  to  hand lay a section of liner in  the 8 in.  (20 on)
non-lined section.  This would have been accomplished by using a section of
liner bag which was saturated with  an  epoxy resin capable of curing at the
ambient temperature in the manhole.
Figure 20. Pneumatically-operated right-angle carbide tip power
           saw used to cut out ends of liner.

     Care  should be taken  when determining  the length of  bag required to
serve  each application.  Consideration must  be given  to  the  diameter of
line,  length of  line,  and  the inversion  head proposed  to be  used.  The
problem associated with a bag that is too short are apparent.  The problems
with a bag that  is  too  long are not so apparent but are quite real.   A bag
that  is too  long  means  extra  cost  for  wasted  bag  and  resin  and extra
manpower to remove  the uninverted  cured portion of the bag.  In addition to
the above  problems,  a bag with  a  long uninverted section  prevents the hot
water  in  the lay flat hose from being  discharged at the  end  of the liner
bag; thereby, potentially adversely affecting the liner cure.

     Special consideration  should be  given in the future development of the
product to safety factors  during installation  and curing.   Care to protect
workmen, spectators, and equipment  from hot water should be observed by the
use of rubber wear  and  protective  shrouds.   Any time  personnel  enter the

                                     51

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manholes, self-contained breathing apparatus/ helmets, and harnesses must be
worn.   Strong volatile styrene odors are  created during this  process, to
which prolonged exposure should be avoided.

     If  installation is  made  during  the night,  to take advantage  of low
sewer flows, the running of equipment such as pumps, boilers, and trucks may
cause sane  problems because of noise  in residential areas.   This should be
evaluated  when scheduling  installing  times and  satisfactory arrangements
should be made with those involved.

     The next step was the reinstatement of the services.  This portion of
the  sewer   relining  technique  is  unique to the  Insituform  procedure.  It
requires the  remote guidance  of a cutter, called an Insitucutter, operating
within  the  sewer  itself.   The  Insitucutter  is  similar to a pneumatic  drill
or router and is operated in conjunction with the  internal inspection camera
(Figure 21).

     The camera-cutter  combination are  pulled  in tandem  through  the  newly
lined sewer in such a way that  the camera continually views the cutter.  The
cutter  is  located  adjacent to  the location  of each service  which  has been
previously  determined and recorded during internal inspections.

     In addition to the previously-recorded locations of the services, they
may  also be  detected visually on the  interior  of  the  newly-lined  pipe;
services appear as  convex areas on the pipe wall.  The operator viewing the
service  locations  positions  the  Insitucutter  by  watching a  television
monitor.  He  also  may place a  microphone in the sewer for audio reference,
since there is a distinctive  difference in the  sound levels noted between
cutting the liner material and  the actual conduit material.

     The Insitucutter is capable  of movement  in six  distinct  directions.
The  operator,  by both listening and watching  the monitor, then proceeds to
cut  out the liner  material covering the service  opening.   Excess  resin in
the  liner  bag migrates into the service joints and forms a seal-like weld
between the walls of the service pipe and the liner in the main.

     In the Northbrook test sections there were no factory installed wyes or
tees  present.  The two  6  in.  (15 cm)  service  connections in the  sewer
between Manholes No. 2 and 3 were break-in type connections.  Pre-Insituform
inspection  revealed that the  services  protruded into the pipe about one in.
(2.5 era).   Although it would have been  possible to line  the sewer without
removing these protruding taps, it was decided that they should be corrected
because  of the  physical restrictions  to  the flow  they presented.   Each
service  connection was  located,  exposed,  and  the protruding  tap removed
prior to the  lining.   The  sheeted  excavations also provided an excellent
point of view for  the spectators to  see the Insituform  reporting  into the
sewer (Figure 22).
                                     52

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Figure 21.
A television camera lower left faces the Insitucutter
which is used to remotely reinstate the services.
The cutter is controlled by an operator who views the
cutting operation from the television van pictures
in the background.
                               53

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     In order to  simulate a service renewal, an ABS saddle tee was strapped
to the pipe  in  the area of the old service  (Figure 23).   The operator then
proceeded to remotely open the tap with  the Insitucutter (Figure 24).  The
end results  snowed the cutting system quite capable of remotely sawing and
removing  the   material   covering   a  service  connection.   As  previously
mentioned in this report, problems are created for the service process when
water  stands in  the service  behind the  liner.   When  the  spinning drill
pierces the  Insituform covering  over the  service to be  opened,  water and
liner material  are splashed in every direction,  including on the lens of the
camera; thus, significantly impairing the operators view.  Should the debris
become heavy, the camera-cutter assembly must be withdrawn from the line for
cleaning.  This situation can  cause a considerable slow-down in the opening
of service taps.   For this reason, all customers served by the sewer should
be notified  in  advance  that water  will be shut off prior to rehabilitation.
This  alone  may  not totally  relieve  the  situation  in that  many  times
infiltration in  the  service line  may backup  behind the  lining.   Service
connections  should therefore be cut  out  as soon  as is  feasible  after the
liner has cured.

     Experience has shown that the average service connection can be renewed
by the Insitucutter in approximately 15 minutes.  If there are many services
to be  renewed  it is  presently the  praclice to  travel  the length  of the
lining and cut  a small relief hole in each service dimple.  This prohibits a
build-up  of  water  from  either infiltration  or customer  use of  sanitary
facilities.   After   all  service  connections  have  been   relieved  the
Insitucutter then commences to reinstate  each service to full bore opening.
This procedure  in most  cases  relieves  the  requirement  for providing any
alternative  sanitary facilities.

     Upon  completion  of  the  opening   of  the   service   connection,   a
post-Insituform internal  inspection was  performed.  This  post-inspection
revealed the sewer to be  completely relined with a joint-free smooth liner.
It was  also noted when comparing  the  pre-Insituform video  tapes  with the
post-Insituform video tapes that  in  areas of broken pipe  that  the ceiling
subsidence of the broken  material  had lessened.   This occurrence should not
be anticipated  in every case.

     As  previously-noted,  the  rehabilitation  performed resulted  in  the
improvement of  the pre-lined section  in many areas:

     1.  Manning's Roughness Coefficient of the pipe decreased
         from 0.014 (assumed) to   o.oos-o.009

     2.  Capacity of the  line was increased from 1.0 MGD  (pre-lined) to
         1.6 (post-lined).

     3.  Structural integrity and life of the sewer were enhanced.

     4.  Clear water flow into the line was reduced to a negligible amount.
                                     54

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en
01
    Figure 22. Sheeted excavation at break-
               in service connection shown
               after lining was installed
               and before service was rein-
               stated .
Figure 23. ABS saddle tee strapped  up-
           side down to the sewer pipe
           to simulate service  connec-
           tion .

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Figure 24. Service connection renewed by the Insitucutter,
                               56

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PHYSICAL PROPERTIES OF LINER

     Initially  it  was  intended   to  perform  an  exhaustive  battery  of
destructive  physical tests on sairples of Insituform which were actually cut
from  the  in-place liner.   However,  due to  the curvature of  the samples,
laboratories were unable  to  execute  the  required  analyses  per A.S.T.M.
standards.   For this reason, flat samples of  the cured liner material which,
by statement from the manufacturer  (Appendix  A), were of identical materials
and thickness and  cured  in the same  manner  as  the Northbrook  test section
were  made and submitted  to an approved,  unbiased  testing  facility.   The
results  received  from the laboratory analysis  are presented  for review as
Appendix  B  of this  report.  The  data indicates  the cured  liner to  be  a
tough,   tenacious  material  with  substantial  structural   integrity  and
inertness  to  chemically-aggressive environments.   Although  some chemicals
reduced  the strength properties of the liner,  the ultimate  values for the
parameters after  exposure  remained acceptable.   The product  apparently has
excellent  flexural,  shear,  and fatigue properties which  render it suitable
for use in  sewer  rehabilitation  work,  where traffic loadings and backfill
shifting create common problems.   Fatigue tests  indicate the cured liner to
have  properties suitable for the lining of  sewers (Table 7).
                 TAHT.B 7.  TVPTCAI. MATEBTAf. PtOTPPRTTPS ny niHTO mSTTCPOM
                                   VERSUS PVC (TYPE PSM1
Property
Tensile Strength PSI
(N/m2xl05)
Modulus of Elasticity
Tension PSI
(N/a2xl05)
Plexural Strength PSI
(N/B2xlOs)
Flexural Modulus PSI
(N/B2xl05)
Compress ive Modulus
PSI (H/B2xl05)
Coefficient of Thermal
Expansion in in/ln°C
or cm/em/°C
Manning *n* Coefficient
of Roughness
ASTM Test
Method
D-638
D-638
D-790
D-790
D-695


Insituform Liner
Northbrook Test
Section
5,420 (382)
475,000(33474)
9,320(656)
403,000(28400)
15,500(1092)
5.96x10-5
.008-. 009
PVC
7,000(394)
400,000(28889)
11,000(775)
-
9,000(634)
5.2XNT5
.008-. 009
          Note:  Material properties of cured Insituform and PVC can be
               significantly different than those shown above when
               different resins are used.
                                       57

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     Driver, Olson  and DeGraff performed a hydrostatic pressure test on  a 5
ft  (1.5 m)  long section  of  unsupported  lining which  was  taken from  the
Nbrthbrook  installation.  A  12 ft  (3.6  m)  length  of lined vitrified clay
pipe between Manhole No. 2 and Manhole No. 3 was excavated and  removed.   The
removed section of pipe was replaced by a section of 12  in. (30 cm) diameter
ABS truss pipe.   The  12 ft (3.6 m) test section was then  taken to Rockford,
Illinois/  where  a  5   ft  (1.5  m)  section was  cut  from the 12  ft  (3.6  m)
length.  The test section was  then inserted inside a 15  in. (38 on) diameter
asbestos  cement  pipe.   To hold  the liner  in the  center  of  the asbestos
cement pipe  and to act as forms  for cement bulkheads for  each end retainer
rings were then glued to the liner and the inside of the asbestos  cement pipe
with  PL200  mastic  cement.   Steel  pins  were inserted through  the asbestos
cement pipe into  the retainer  rings at approximately 6 in.  (15  cm) intervals
to  reinforce  the  retainer   ring.  Before  the  second  retainer  ring  was
inserted, the 2 in. (5 cm) annular space was filled  with cement and then  the
second retainer ring was installed in the same manner as the first.  Two  3/8
in. (10 mm) holes were drilled and tapped through the asbestos  cement pipe 8
in. (20 cm) from  either end.   One  hole was fitted with a pet cock; the other
with an air pressure  gauge and filler valve.  The end with the pet cock was
raised about one  in.  (2.54 cm)  higher than the other end so that as the void
area was filled with water through the filler valve  air  could escape through
the open pet cock.  When the void  was totally filled with  water the pet cock
was closed and  the  water filled liner removed.  A target  was then placed  at
one end of the pipe and a video camera mounted on a  tripod was  placed at  the
other end.  The camera and target  were so arranged as to allow  the camera  to
view  the  inside  of  the liner during the test.   Cylindrical  rings  on  the
target  made  it possible for  the  camera to estimate the  liner deformation
during the  test.   Water was used  in  the void area  instead of  air to allow
visual observation of any leaks as well as to eliminate danger  of  explosion.
An air  hose  was attached to  the  filler  valve and air pressure was applied
until  deformation  of the  liner  indicated that  deformation  of the  pipe
occured  around  50 PSI  (3.515 Kg/cm2).   when  the  pressure  was  totally
released  the   liner   returned  to  its  original   cross-section.   Visual
inspection of the material after testing revealed no apparent cracking which
indicates that  the liner  is  a relatively flexible  material (see Figure  25
for diagram of test set up).

     Since  the  12  ft  (3.6  m)   field  specimen  that  was used for  the
hydrostatic pressure  test included a  service connection  and joints  of the
original pipe, visual  inspection  indicated  excellent migration of the resin
material into the joints and  even into  service  connection  joints, creating
an additional seal to infiltration.
                                       58

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                              AIR GAUGE
in
vo
                   WOOD RETAINER RING
                                               FILLER VALVE
                          •COLLAPSED AREA
                               PET COCK
                    TV CAMERA
                                       1
                                                      VOID AREA (FILLED WITH WATER) f.:;
                                                                                   WOOD RETAINER RING
                                                                                    (CEMENT BETWEEN 2PCS.
                                                                                      WOOD)
                                                        ^I'-
                                                                               I  I
                                                                               I  I
                                                                               I  I
                                                       VOID AREA
                                          Jii
                                     m
                                         BLOCK
                                                   •TARGET
                                                                              BLOCK
                                             LONGITUDINAL  SECTION
                                GAUGE
             TARGET
                                   CEMENT ASBESTOS PIPE
WOOD RETAINER RING
                                      INSITUFORM
                                      LINER
                                               COLLAPSE OF PIPE
                                                 UNDER PRESSURE
                       END VIEW                                     END VIEW
                         BEFORE TEST                                    DURING TEST
                                   Figure 25.  Diagram  of test set  up.

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COST EFFECTIVENESS OF INSITOFOIffl L.IMER
     In   this   project  it  was   extremely  difficult   to  extablish  the
cost-effectiveness  of  the  Insituform  technique  with  respect  to  this
application.  The main  difficulty lies in the prices charged for contracted
installation services.   Insituform  East,  backed by  the international firm
agreed to perform all work necessary  to  inspect and install  the liner for
the  price of $16,965.30,  which was budgeted in the Grant Application and
therefore  locked in.   Ancillary  excavation and  overpumping functions were
handled by the  Village of Northbrook.  However, the total price for these
appurtenant functions was $25,245.41, which far exceeded  the insertion cost,
and  was  due mainly to  the  requirement  of  a  sophisticated  bypass  system
operated  over  an extended  period  of time  as  well  as  added  excavation
necessary to expose service connections.

     As documented by  the site  testing  done  by the  Engineer,  the total
amount of  Infiltration  removed  from the sewers in the two  test sections was
approximately 23,300  gallons (   8.8 M- )  daily,  or 16.2 gallons ( .06 M3 )
per  minute  during a period when  the ground  water level was relatively low.
This data reduces to an actual project  cost of $2,605.60  for each gallon per
minute of infiltration eliminated.  Although this unit cost does not convert
into a cost-effective value for this situation, it must be  realized that the
infiltration in the  downstream test section was  low during the test period
while the overpumping and excavations costs were extremely high.

     The  Sewer  System  Evaluation Survey  conducted  in  1977 concluded  that
under  the  then  existing high  water table condition,  the  clear  water
contribution within  the two  test sections was  67.05 gallons  (.25 M3)  per
minute.  The clear water contribution  is  typically  directly dependent upon
the elevation of the ground water table in the area.  Typical current prices
for  rehabilitation with Insituform liners in  large-footage situations are
shown in Table  8 below.
TABLE JL INSITUPC
Sewer Diameter
in.
6

8


10


12


15


Liner Thickness
mm
3
6
3
6
9
3
6
9
6
9
12
6
9
12
3FM COSTS
Cost per
L.F.
$33.00
$39.00
-
$42.00
$46.00
-
$44.50
$48.00
$47.00
$51.00
$55.00
$52.00
$57.00
$62.00
Cost per
m
$108.27
$127.95
-
$137.79
$150.91
-
$146.00
$157.48
$154.20
$167.32
$180.46
$170.60
$187.00
$203.42
                                       60

-------
Table 8. (continued)
Sewer Diameter
in.
18

21


24


Liner Thickness
nro
9
12
9
12
15
9
12
15
Cost per
L.F.
$62.00
$66.00
-
$74.00
$80.00
$74.00
$80.00
$86.00
Cost per
m
$203.42
$216.53
-
$242.78
$262.47
$242.78
$262.47
$282.15
     A.  Add $1,900.00 per line for overpumping
     B.  Add $1.90 (6in.-15in.) and $2.50 (15in.-30in.) per foot for
         preliminary cleaning and inspection.
     C.  Add an undefined amount for traffic control and
         mobilization.

     Different alternatives of sewer  rehabilitation were considered for the
Northbrook  site.   Due  to the percentage of  failed pipe  within  the test
section  specific point  repair  and  grouting  were overruled  in  favor  of
complete  section  replacement.   A  cost  estimate  for  complete  section
replacement along a parallel path is as follows:

        Item                     Units        Unit Cost        Total
Sanitary Sewer, 12 in. Dia.    589 L.F.           24.00      14,136.00
Dewatering                     589 L.F.           12.00       7,068.00
Manholes                       3 each          1,600.00       4,800.00
Services                       2 each            400.00         800.00
Granular Backfill              200 C.Y.           10.00       2,000.00
Site Restoration                 1 L.S.       17,596.00      17,596.00

    Totals -                                             -  $46,400.00

     Conventional  slip-lining was  also  considered,  however,  due to  the
amount  of badly-broken pipe  and  offset  joints as  well  as the  capacity
problems, it was decided not to be a viable alternative in this situation.

     Using the prices  in Table 8 and  applying them to  the  Northbrook test
site in  which 585 L.F.  (175m)  of sewer  was  rehabilitated,  the anticipated
construction cost for the work may be estimated:

     1.  Line 585 L.F.  (175m) of 12 in.
          (30.5cm) diameter sewer with 6mm bag
         8 $47.00/L.F	$27,448.00
     2.  Line preparation	$ 1,111.50
     3.  Overpumping	$ 1,900.00
     4.  Mobilization	$ 1,500.00
         Total                                            $31,959.50

     This  estimate  reduces  to a construction cost of  $54.63 per L.F.  of

                                      61

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sewer lined.  It is shown above and is relatively obvious  that  in  many  appli-
cations, the unit cost of rehabilitating a deteriorated sewer by the  Insituform
technique could be much more economical  than the replacement or slip-lining
alternatives, where factors such as traffic control, service-reconnect!on, and
surface restoration may run the unit costs for these options to over  $100.00
per L.F.  The test and seal of joints with grouting material generally  allows a
great cost savings over these three techniques.  However it does not  lend  itself
to the rehabilitation of cracked or broken conduit (which  was prevalent  in this
site).

     The useful life of the Insituform liner is assumed to be similar to new
pipe based on the properties of strength, and resistance to reagents  as  exhibited
in Appendix B.  Long-term data from actual installations is unavailable  because
of the recent development of the method.

     Insituform of North American, Inc., Memphis, Tennessee, is presently  in-
stalling liner bag manufacturing equipment in Memphis.   In addition to  bag
manufacturing Insituform of North America. Inc. will license installers  and
train all future installers in the United States.  Probably as  more licensed
installers enter the Insituform field, greater competition will result  for
work, with an accompanying reduction in prices charged.


FOLLOW UP REPORT

     Driver, Olson and Degraff inspected the test sections on March 24,  1980,
approximately six months after the Insituform installation, in  order  to  deter-
mine the effects that time and the elements have had on the Insituform  lining.
Personnel were dispatched to the site with sewer cleaning  and internal  inspec-
tion equipment.  Each test section was thoroughly cleaned  and televised, with
the results documented on videotape.  Comparison of those  tapes with  those made
just after lining was completed indicated there to be no detectable changes  in
the appearance of the liner over its life.  No infiltration was perceived
throughout the test stretches in the follow-up tapes.  Manholes in the  test
section were investigated in an attempt to establish whether infiltration  had
migrated to the manhole joints.  No measureable infiltration was  noted  in  the
manholes; however, this may be attributable to a ground water table that was
relatively low and immeasurable during the inspection.

      In an effort to determine what effects an extended period of  backfill
loading had on the bare liner, a 1 ft2  (929 cm2) section of the top of  a clay
pipe was removed prior to lining and a PVC vertical riser  was placed  against
the Insituform liner and extended to the surface.  The elevation  of the top  of
the liner bag was shot prior to backfilling the area and again during the  6-
month follow-up study.  These measurements indicated the liner to  be  depressed
less than one-eighth of an in. (3mm) at the later inspection, indicating very
favorable structural properties of the  liner.

     The follow-up internal inspection of the test section showed  absolutely
no build-up of material on the invert of the line, indicating that the  flow
properties of the section had been significantly improved.  The limited follow-
up study seems to indicate that the Insituform liner is an effective  and dur-
able product for sewer rehabilitation.


                                       62

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                            APPENDIX A
                     (PIPES AND STRUCTURES) LIMITED
                          REGISTERED OFFICE:

            HORSLEY ROAD. KINGSTHORPE. NORTHAMPTON. ENGLAND

               TJ..VI—•• 'n'.(H) ;t96C67/3''  TO'W 3H940lnlltu G
                      Registered in England No. 996266
Driver-Olson & Associates
6933 Elm Avenue
Rockford,  Illinois  61111

Attn:  Mr.  F.  T.  Driver, P.E.
                                       Re:   Tnsituform test samples
                                            for Northbrook, 111.
                                            EPA Project
Dear Mr. Driver:

Pursuant to your request, please  be  assured that the Insituform
samples supplied for testing are  representative of the cured
liner  installed in the 12 inch  diameter pipe in Northbrook,  111.

If I can be of any further assistance,  please contact the  writer.
Yours  sincerely,

INSITUFORM (PIPES & STRUCTURES)  LIMITED
Eric  Wood
                                63

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  CLIENT:
  SUBJECT:
                                      APPENDIX  B

                         United States Testing Company, Inc.
                                  Engineering Services Division
                            U13 PARK AVENUE • HOBOKEN. NEW JERSEY 07030 • 201-792.2*00

                                          REPORT OF TEST
Driver, Olson  &  Associates
6933 Elm Avenue
Rockford,  Illinois  61111

Physical Properties
                                                                            77486

                                                                           NUMBER

                                                                        July 9. 1980
              REFERENCE;

              Driver,  Olson & Associates  Letter dated  10/15/79
              SAMPLE IDENTIFICATION;

              One (1) sample of material  submitted and  Identified by
              the Client as:

                             Institufonn  Sewer Material

              TESTS PERFORMED;

              The submitted sample was  tested for the following properties  in
              accordance with the ASTM  Test Methods listed below:
              A.
              B.
              C.
              0.
              E.
              F.
              G.
              H.
              I.
              J.
                       Property
                                                   ASTM  Test Method
    Tensile  Properties                     0-638
    Shear  Strength                         0-732
    Flexural  Properties                    0-790
    Deformation Under Load                 0-621
    Coeff. of Linear Thermal  Expansion    D-696
    Deflection Temperature                 0-648
    Flexural  Fatigue                       D-671
    Compresslve Properties                 0-695
    Bearing  Strength                       0-953
    Resistance to Reagents                 0-543
 Page 1 of
       ng
           Testing Supervised by

 !?        Frank Razzuoli


in:     New York  •  Chicago  • Lot A*f*«n • Houuon
                                                                  SIGNED FOi
                                                            Tulu
                                                          Frank
                                                          Assistant Vice  Presldcr.t
                                                          Engineering Division
                                                      Memphis  •  Reading  •  Richlai.-'
mi MPOOT >miu ONLY TO TNI tuioino o« noeiBuMi io»Tinu ..o TO mi unriim TUTU T«I TUT mgin AM HOT IICUMIIIT I«OIC*TI»I.
• IFVUIMTATIVf or THI QgiLITIII Or TNI LOT riO« MICH TMI IJ«*\I ••! TAKIn Off Or ArrftBIHTkT IDINTICJIk 0« tlHIUN MOOVCTI NOTNI«« COHTAI«l'tt
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ran if illuu imiu» mciriuuT iMCtruo  owi tiroiii ••« .€->!•• «•« >a« mi ucuniol ail or i«i CLICHT TO ••«•  ralT «•• >oo«i •
»0 TNtT MO TNI •••! Or TNI UCITIO ITITU TUTIM «•»«<» '"C M ITI IUU 3" I»II«>U III "OT TO II HMD U»0«« ««T CIKUNfTINCU III Ib.
TIIIM TO TKI u«ut niiiie »a ««T >OT n giu i» I«T OTNII ••••» CITNOIIT ogi nwi wiinin  irraenk UBPIU »OT OUTNTU '• "ti
in MTtiiu « mtiimu* or TMIITT UTS

-------
CLIENT:
               United States Testing Company. Inc.

Driver, Olson & Associates
           TEST RESULTS:

                   Test and Units

           A.  Tensile Properties
              (1)   Tensile Strength, ps1
              (2)   Modulus of Elasticity, psl

           B.  Shear Strength. ps1

           C.  Flexural Properties
               (1)   Flexural  Strength, psl
               (2)   Flexural  Modulus, psl

           0.  Deformation Under Load. pet.
                (800 psi.  158°F. 24  Mrs.)

           E.  Coefficient of Expansion,  in/in/°C

           F.   Deflection  Temperature,°C
               (1)   9 66 psl
               (2)   9 264  psl

           G.  Fatigue Endurance Limit, psi 0 10  cycles

           H.   Coinpressive Properties
               (1)   Compressive  Strength, psl
               (2)   Compressive  Modulus,  psi

           I.   Bearing Strength,  psi
               l.@4% Deformation
                   @  Maximum
      77486
     Number

July 9, 198:
                                                Determined
                                                    5,420
                                                  475.000

                                                    8,150
                                                    9,320
                                                  403.000

                                                    0.149
                                                   5.96 x 10'
                                                     106
                                                    92.5

                                                    1360
                                                 15,500
                                                325.000
                                                   3330
                                                   5910
                                          65

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                                      Resistance to Reagents

   Reagent                               Tensile Properties                            Compressive Properties
168 Hr.  itmnerslon               Tensile Strength.psl   Modulus, psi          Comp. Strength. psl         Modulus,  psl
1.
2.
3.
4.
5.
6.
7.
8.
9.
Acetic acid. 70X sol. 9 77°F
Annonla. 51 sol. 9 77°F
Brine. 101 sol. 9 122°F
Calcium Hydroxide 0,181 Sol.
995°F
Diesel Fuel 9 95°F
Hydrochloric Acid. 351
Sol. 0 77°F
Gasoline • 77°F
Nickel Plating. Sol 9 133°F
Sulfurlc Acid. 151 Sol. 9 86°F
5860
4810
4670
5430
4300
5110
5100
4720
5280
(<8X)
(-1U)
)-141)
(tO.21)
)-211)
(-61)
(-61)
(-131)
)-31)
435
465
474
460
568
446
457
464
471
.000
.000
.000
.000
.000
.000
.GOO
.000
.000
14.300
14
13
14
13
13
14
11
13
.800
.300
.300
.800
.700
.800
.800
.900
(-81)
(-51)
(-141)
(-01)
(-1H)
(-121)
(-5X)
(-241)
(-101)
298
297
253
317
250
271
311
260
291
.000
.000
.000
.000
.000
,000
.000
.000
.000

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CLIENT:
                United States Testing Company. Inc.

Driver. Olson ft Associates
                                                                                77486
                                                                                Nu
          DATA:
          Determination

               1
               2
               3
               4
               5

           Average
                                                                                 umoar

                                                                             July 9, K
                                 Tensile  Properties
                                                                Initial  (As Received)
                   Cross Sectional
                   Area. So.  In.

                      0.133
                      0.133
                      0.118
                      0.134
                      0.134
Tensile Strength, psi

      5270
      5600
      4250
      6050
      5930

      5420
 Modulus of    i
Elasticity x 10"

     4.52
     4.70
     5.15
     4.53
     4.83

     4.75
                                         After 163 Hrs.  in 705 Acetic Acid Solution 9
               1
               2
               3
               4
               5

          Average
               1
               2
               3
               4
               5

           Average
               1
               2
               3
               4
               5
           Average
                      0.127
                      0.133
                      0.119
                      0.125
                      0.122
                      0.127
                      0.124
                      0.-131
                      0.123
                      0.133
                      0.120
                      0.129
                      0.132
                      0.132
                      0.127
      6090
      5350
      6170
      5820
      5840
     4.26
     4.49
     4.30
     4.10
     4.59
                                           5860                    4.35

                               After 168 Hrs.  in 55 Airmonia Solution 3 77°F
5570
4110
4790
5240
4340
A. 68
4.24
4.42
4.79
5.10
                                           4810
                                                                   4.65
                                         After 163 Hrs.  in 10% Brine Solution P 122 f
      3990
      5110
      5190
      3740
      5340

      4670
       64
       27
       06
       ,32
     4.43
     4.74
                                          67

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                         United States Testing Company. Inc.

CLIENT:    Driver,  Olson  & Associates


                            Tensile Properties (Cont.)
Determination

      1
      2
      3
      4
      S
 Average
      1
      2
      3
      4
      5
 Average
      1
      2
      3
      4
      5
 Average
      1
      2
      3
      4
      5

  Average
                                                                     77486
                                                                     Number

                                                                  July 9, 1980
After 168 Hrs.
Cross Sectional
1n 0.

Area* So* In- Tpnsif'|A *••
0.128
0.128
0.135
0.129
0.126

After 168 Hrs
0.135
0.128
0.125
0.135
0.134

After 168 Hrs.
0.133
0.127
0.126*
0.134
0.130

After 168 Hrs.
0.133
0.121
0.130
0.125
0.133

5390
5150
4960
5750
5890
5430
182 Calcium Hydroxide
Solution 8 95 F
Modulus of 5
rongth, p«< Fl^^»*/-<*y » Tfl3
.60
.60
.55
.34
.94
.60
. 1n Diesel Fuel 0 95°F
4220
4180
4480
4070
4560
4300
1n 35
5160
4810
5290
4780
5500
5110
6.15
5.99
4.83
5.49
5.96
5.68
S Hydrochloric field
Solution 0 77°F
4.48
4.79
4.24
4.54
4.24
4.46
in Reoular Gasoline 9 77°F
5690
4630
5680
4810
4670
5100
4.70
4.46
4.58
4.66
4.47
4.57
                                68

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                          United States Testing Company, Inc.
                                                                                 77486
CLIENT:   Driver, Olson & Associates                                           Nurnbw

                                                                              July 9.  i960
                                 Tensile Properties  (continued)

                                         After 168 Mrs.  In nickel  Plating Solution 9  133°F
                              Cross Sectional                             Modulus  of      s
          Determination       Area. Sq.  In.      Tensile Strength, psl     Elasticity,  x  10

               1                  0.130                5140                 4.88
               2                  0.134                3310                 4.47
               3                  0.121                 4840                 4.66
               4                  0.127                5460                 4.36
               5                  0.126                4840                 4.81
           Average                                     <720                 4-6*
                                            After 168 Mrs.  in 15S Su If uric Add  „
                                            	Solution 9 86°F

               1                  0.126                4910                 5.83
               2                  0.130                5620                 5.03
               3                  0.127                5160                 4.37
               4                  0.136                5020                 4.32
               5                  0.13S                5720                 4.02
           Average                                     5280                 4.71
                                          69

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                            United States Testing Company. Inc.

  CLIENT:   OHver, Olson & Associates
Determination

      1
      2
      3
      4
      5

   Average
                                                           77486
                                                           Nuniocr

                                                        July 9. 1980
                                     Shear Strength

                  Shear Area. So.  In.        Shear Load. Lbs.
0.766
0.747
0.763
0.760
0.763
  6300
  6320
  5980
  6260
  6100
Shear Strength. ps1

     8220
     8460
     7840
     8240
     7990

     8160
                                   Flexural Properties

Determination
1
2
3
4
5

Dimensions, In.
0.514 x 0.249
0.536 x 0.242
0.503 x 0.249
0.499 x 0.249
0.478 x 0.243

Scan, In.
4.00
4.00
4.00
4.00
4.00
Flexural
Strength, psi
9790
9360
89SO
9150
9360
Mod. of Elasticity K
In Flexure, psi
4.03
3.97
3.96
4.07
4.09
x 10"





     Average
       Determination

             1
             2

         Average
                                                         9320
                                                    4.03
                          Deformation Under Load. 800 os1 9 148 F. 24 Mrs.

                         Onclnal Heicht.  In.   Deflection. In.      Deformation, pet.
    0.5326
    0.5410
     0.0006
     0.0010
        0.113
        0.185

        0.149
                             Coefficient of Linear Thermal Expansion

     Determination    Initial Length.  In.    Temperature Range. °C   Coeff. of Expansion in/W°C
             1
             2

         Average
   1.986
   1.986
-30 to 4-30
-30 to +30
     5.75 x 10
     6.17 x 10

     5.96 x 10
:!
-5
                                            70

-------
Cross Sectional
Area, Sq. In.
0.147
0.152
0.140
0.170
0.148
Initial
Compress ive
Strength, psl
14.800
15, 900
15.400
15.500
16.000
(As Received)
Modulus of Elasticity
In Compression, psl x
3.09
3.21
3.40
3.27
3.30
105

                          United States Testing Company, Inc.

CLIENT:    Driver, Olson i Associates



                                Compressive Properties
 Determination

       1
       2
       3
       4
       5

    Average
       1
       2
       3
       4
       5
   Average
       1
       2
       3
       4
       S

   Average
                                                           77486
                                                           Number

                                                     July 9. 1980
0.123
0.133-
0.136
0.137
0.137
0.138
0.123
0.146
0.146
0.136
                       15,500
                      3.25
                                     After 168 hrs.  in  708 Acetic Acid Solution 9 77°F
14,700
14.200
14,100
14,300
14,200

14.300
3.01
2.96
3.08
2.32
3.03

2.98
                                    After 168 llrs.-in  SZ Ammonia Solution 9 77 F
14.700
14.300
15.300
15.100
14.800

14,800
2.78
2.85
3.
3.
19
11
2.94

2.97
       1
       2
       3
       4
       5

    Average
0.134
0.139
0.141
0.138
0.133
                                   After 168  Hrs.  In  108 Brine Solution 9 122 F
13.100
13.400
13.800
12.500
13.500

13.300
2.67
2.44
  56
  36
  63
                                             2.53
                                          71

-------
                         United States Testing Company. Inc.

CLIENT:    Driver. Olson & Associates



                           Compressive Properties (Cont)
                                                                         July 9, I960
Determination

      1
      2
      3
      4
      5
  Average
      1
      2
      3
      4
      5

 Average
                  Crass  Sectional
                  Area.  Sq.  In.

                     0.125
                     0.137
                     0.140
                     0.139
                     0.141
                     0.136
                     0.138
                     0.126
                     0.135
                     0.143
tompressive
Strength, ps1
14,300
14,400
14.400
14.100
14.400
14.300
After 168 Hrj. in
13,400
14.700
12.900
13,300
14,500
noauius or tiasnciij
In Caraoression psi >
3.12
3.15
3.18
3.19
3.23
3.17
Diesel Fuel 0 95°F
2.33
2.74
2.61
2.57
2.34
                                           13.800
                         2.50
      1
      2
      3
      4
      5

 Average
                     0.138
                     0.137
                     0.136
                     0.139
                     0.134
                                   After  168 Hrs. 1n 355 Hydrochloric Add
                                                         Solution 0 77°F
13,600
13.800
13,500
14,000
13.700
2.65
2.78
2.69
2.77
2.66
                                           13,700
                        2.71
                                  After  168 Hrs. In Regular Gasoline P 77°F
      1
      2
      3
      4
      5

Average
                     0.139
                     0.118
                     0.140
                     0.140
                     0.143
14,400
14,700
15.300
15,200
14.500

14.800
2.92
3.07
3.16
3.09
3.31

3.11
                                        72

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CLIENT:
                United States Testing Company, Inc.
                                                                       77486
Driver. Olson & Associates                                           Numtwr
                    Compressive  Properties  (cont)                July 9, 1980
  Determination

        1
        2
        3
        4
        5

     Average
Cross Sectional
Area. SQ. In.
0.140
0.141
0.136
0.141
0.136
After 168 Mrs. In Nickel Plating Solution 9 133°F
Conpresslve Modulus of Elasticity 5
Strenoth, ps1 In Compression os1 x 10
13.200 1.96
9.700 2.36
13,300 r.Sl
12.400 2.96
12.500 3.21
                                       11.800
                               2.60
        1
        2
        3
        4
        5

     Average
             0.129
             0.138
             0.131
             0.139
             0.138
                                    After 168 Hrs.
                                          In 15Z SylfuHc Add
                                          Solution 9 86 F
13.600
14.300
13.700
14.000
13.900
2.86
2.93
2.95
2.89
2.92
                                      13.900
                               2.91
                                Bearing Strength
     Determination

          1
          2
          3
          4
          5

       Average
             Thickness. .In.

               0.274
               0.279
               0.285
               0.337
               0.274
Bearing
Hole Oia.
In.
  0.250
  0.250
  0.250
  0.250
  0.250
 Bearing Strength,  psi

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                          United States Testing Company, Inc.

CLIENT:  Driver.  Olson  ft  Associates




         TEST RESULTS:
                                   77486
                                   Number
                            July 9. 1980
Flexural  Fatigue


Average Thickness


0.266
                                     Stress  Level.  ps1


                                          2000


                                          1500



                                          1400


                                          1350
                    Cycles to Failure
                           26.000
                           27.000

                          138,000
                          193,000
                          112.000

                          279.000
                          345,300

                        10.000,000 +
                        10.000,000 +
             Fatigue Endurance Limit:
'360 ps1  9 10  cycles

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CO
tn
UJ
flc
                                                  CYCLES  TO  FAILURE

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                                   TECHNICAL REPORT DATA
                            (Please read Instructions on the reverse before completing)
I REPORT NO.
                             2.
                                                           3 RECIPIENT'S ACCESSION NO
I. TITLE AND SUBTITLE
 "DEMONSTRATION OF SEWER  RELINING BY THE INSITUFORM
   PROCESS,  NORTHBROOK,  IL"
                                                           S REPORT DATE
             •. PERFORMING ORGANIZATION CODE
 AUTHOR(S)

   F.T.  Driver and M.R. Olson
             B. PERFORMING ORGANIZATION REPORT NO.
> PERFORMING ORGANIZATION NAME AND ADDRESS

   Driver, Olson-Degraff  & Associates
   77 Seventh Street
   Rockford,  Illinois  61104
                                                           10. PROGRAM ELEMENT NO.
             11. CONTRACT/GRANT NO.
                    R-806322
12. SPONSORING AGENCY NAME AND ADDRESS
                                                           13. TYPE Of REPORT AND PERIOD COVERED
   Municipal  Environmental  Research Laboratory  -  Cin.,OH
   Office of Research and  Development
   U.S.  Environmental Protection Agency
   Cincinnati. Ohio  45268	
             14. SPONSORING AGENCY COOe


                  EPA/600/14
IS. SUPPLEMENTARY NOTES
      Contact:  Richard  Field    (201)340-6674
    This study was initiated with the overall objective  of determining the effective-
   ness  of a new process of lining sewers called  Insituform.

    Two  test sections of sewer in need of rehabilitation were lined to evaluate both
   the  effectiveness of the liner in eliminating  infiltration and the liner's effect
   on  the flow characteristics of the sewer.  Physical characteristics of the installed
   liner were tested by running destructive tests on specimens.

    The  conclusions, recommendations and installation procedures described in the text
   in  this report should be of help to potential  users in  determining the viability of
   this  rehabilitation technique as it may apply  to their  needs.  This study documents
   the  fact that the Insituform method of lining  deteriorated sewers is an effective
   process for eliminating infiltration from lines, as well as improving the hydraulics
   and  structural integrity of damaged conduits.  The economical advantages of this
   system are mainly dependent upon physical conditions  of each  application.
17.
                                KEY WORDS AND DOCUMENT ANALYSIS
                  DESCRIPTORS
                                              b.lOENTIFIERS/OPEN ENDED TERMS
                           c. COSATi Field/Croup
   Sewers,  Rehabilitation, Liners,
   Infiltration, Flow measurement,
   Tests
 Insituform,  Infiltration/
 inflow control, Sewer
 rehabilitation, Physical
 properties,  Economics
                                                                                13B
18. DISTRIBUTION STATEMENT


  RELEASE TO PUBLIC
19 SECURITY CLASS (Thil Rtportf
 UNCLASSIFIED
21 NO. OP PAGES
2O SECURITY CLASS (Thit pOft)

 UNCLASSIFIED
                           22. PRICE
EPA Pwm 2220-1 (R««. 4-77)   PHBVIOUI COITION 11 OBIOL.KTC
                                             76

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                                                      INSTRUCTIONS
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      Insert the EPA report number as it appears on ihe cover of the publication.
  2.   LEAVE BLANK
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      Reserved for use by each report recipient.
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      (a) DESCRIPTORS - Select from the Thesaurus of Engineering and Scientific Terms the proper  authorized terms that identify the major
      concept of the research and are sufficient^ specific and precise to be used as index entries for cataloging.
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  22,  PRICE                                                                   _      ««.,,.
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EPA Porm 7220-1 (»«•- 4-77) (R.v.rt.)

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