ENVIRONMENTAL HEAIJTH SERIES
Air Pollution
[Lewi:
A Study of Air Pollution
in the Interstate Region
of Lewiston, Idaho,
and Clarkston, Washington
U.S. DEPARTMENT OF HEALTH, 'EDUCATION, AND WELFARE
Public \Health Service
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A STUDY OF AIR POLLUTION
IN THE INTERSTATE REGION
OF LEWISTON, IDAHO, AND
CLARKSTON, WASHINGTON
PARTICIPATING AGENCIES
The City of Clarkston, Washington
The City of Lewiston, Idaho
Idaho Air Pollution Control Commission
North Central District Health Department, Idaho
State of Washington, Department of Health
Public Health Service, U.S. Department of Health,
Education, and Welfare
U. S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE
Public Health Service
Division of Air Pollution
Cincinnati, Ohio 45226
December 1964
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The ENVIRONMENTAL HEALTH SERIES of reports was established to
report the results of scientific and engineering studies of man's environment: The
community, whether urban, suburban, or rural, where he lives, works, and plays;
the air, water, and earth he uses and re-uses; and the wastes he produces and must
dispose of in a way that preserves these natural resources. This SERIES of reports
provides for professional users a central source of information on the intramural
research activities of Divisions and Centers within the Public Health Service, and
on their cooperative activities with State and local agencies, research institutions,
and industrial organizations. The general subject area of each report is indicated
by the two letters that appear in the publication number; the indicators are
AP Air Pollution
AH Arctic Health
EE Environmental Engineering
FP Food Protection
OH Occupational Health
RH Radiological Health
WP Water Supply and Pollution Control
Triplicate tear-out abstract cards are provided with reports in the SERIES to
facilitate information retrieval. Space is provided on the cards for the user's
accession number and key words.
Reports in the SERIES will be distributed to requesters, as supplies permit.
Requests should be directed to the Division identified on the title page or to the
Publications Office, Robert A. Taft Sanitary Engineering Center, Cincinnati, Ohio
45226.
Public Health Service Publication No. 999-AP-8
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STATEMENT BY COOPERATING AGENCIES
This report is the product of cooperative efforts of the partici-
pating agencies. It represents an adequate description of the air
pollution problems that motivated this study, and provides means to
effect solutions to these problems in an equitable manner. The coopera-
ting agencies agree that much still needs to be done to establish and
implement an effective and reasonable air quality management program
serving the best interests of the two communities and the two respective
states.
-
Jess B. Hawley, Jr., Chairman
Idaho Air Pollution Control Commission
Terrell 0. Carver, M. D. , Administrator of Health
Idaho State Department of Health
Secretary. Idaho Air Pollution Control Commission
Roy W. Eastwood, M.DC, Medical Director
North Central District Health Department
Idaho State Health Department
Bernard Bucove, M. D., Director
Washington State Department of Health
Vincent Uhlenkott,'Mayor
City of Clarkstpn, Washington
7
Vernon G. MacKenzie, Chief, "
Division of Air Pollution, Public Health Service
111
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The Idaho Air Pollution Control Commission, in its letter of May 5, 1964,
to the U.S. Public Health Service stated, "The Idaho Air Pollution Control
Commission will be signatory to the report conditioned on a copy of this
letter being inserted in the report after the signature page --." In
accordance with this statement, said letter is reproduced below.
The inclusion of this letter does not constitute acceptance of nor agree-
ment with statements made in the third paragraph of the Commission's
letter by other agencies signatory to this report.
IDAHO AIR POLLUTION CONTROL COMMISSION
Statehouse
Bois e, Idaho
May 5, 1964
Mr. Austin N. Heller, Chief
Technical Assistance Branch
Division of Air Pollution
U.S. Department of Health, Education and Welfare
Robert A. Taft Sanitary Engineering Center
Cincinnati 26, Ohio
Dear Sirs:
Concluding the hearing held this morning by the Idaho
Air Pollution Control Commission called to consider your revised
report entitled "A Study M Air Pollution in the Interstate Region
of Lewiston, Idaho and Clarkston, Washington", the Commission
Drooerly signed, for inclusion at Page 11, with the qualifications
hereinafter expressed. *
and cooperation in implementing the objectives of such council.
Air Pollution Control Commission, however, wanted it clearly
understood that it does not approve the report in its entirety. There
has been, in our considered judgment, a departure in the report from
the oDjectwity with which we understood the problem would have been
approached. In particular, the Commission feels that portions of
the reoort covering (1) evaluation of air quality, (Z) the odor survey,
(3) the effects of air pollution, and, in particular, the health and
welfare implications, are predicated on inadequate studies and
investigation, and the conclusions therein reached are not supported
The Idaho A,r Pollution Control Commission will be
inserted in the
We do appreciate your revision of Exhibit B in accordance
with our suggestions, and we approve the revised Exhibit B.
IDAHO AIR POLLUTION
CONTROL COMMISSION
JBH:ds
. 9?,
~^
* Page i i i of this report.
t Page 5 of this report.
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TECHNICAL STUDY STAFF
CITY OF CLARKSTON, WASHINGTON
Laurel Barreman, City Clerk
Jack Ewing, Assistant City Engineer
Dave Malsch, City Engineer
CITY OF LEWISTON, IDAHO
Elmer E. Soniville, City Engineer
STATE OF IDAHO, DEPARTMENT OF HEALTH
Arthur Van't Hul, Project Coordinator for Idaho Department
of Health
Vaughn Anderson, Director, Engineering and Sanitation Section
Wayne Heiskari, Sanitarian
NORTH CENTRAL DISTRICT HEALTH DEPARTMENT, IDAHO
George A. Freeman, Sanitarian H and Assistant Director
STATE OF WASHINGTON, DEPARTMENT OF HEALTH
Peter W. Hildebrandt, Survey Director for State of Washington
Department of Health
Roger James, Engineer
Edward K. Taylor, Senior Industrial Chemist
UNITED STATES WEATHER BUREAU
Peter Gertenson, Meteorological Technician, U.S. Weather
Bureau Airport Station, Lewiston, Idaho
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PUBLIC HEALTH SERVICE, DIVISION OF AIR POLLUTION
M. Dean High, Project Director
Willis E. Bye, Assistant Sanitary Engineer
Austin N. Heller, Deputy Chief, Technical Assistance Branch
Seymour Hochheiser, Analytical Chemist
Sanford W. Horstman, Jr., Assistant Sanitary Engineer
CONSULTANT TO THE STUDY
Dr. A. L. Finkner, Associate Head, Statistics Research
Division, Research Triangle Institute, Durham, North Carolina
REPORT PREPARATION
Max E. Burchett * Sanford W. Horstman *
Richard DeSchutter * Paul A. Humphrey
Sidney Edelman Dr. Nahum Z. Medalia *
Harry Heimann, M.D. * Marvin E. Miller
Austin N. Heller Mario Storlazzi
M. Dean High * D. Bruce Turner
Seymour Hochheiser Donald F. Walters
Richard F. Wromble
* Formerly with the Division of Air Pollution, Public Health
Service.
vi
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PREFACE
Recently, air pollution has been recognized as a major
environmental problem because of the nuisance it creates, its damage
to property and vegetation, and its effect on human health. The air
pollution study in the Lewiston-Clarkston area of Idaho and Washington
is a prime example of how joint efforts of federal, state, and city
authorities can delineate the magnitude and extent of an air pollution
problem involving more than one jurisdiction.
This joint study and report is the first necessary step towards
improving the air environment for the people of this area. Its goal is
to provide an understanding of the facts so that effective air resource
management programs can be developed.
V. G. MacKenzie, Chief
Division of Air Pollution
U.S. Public Health Service
vn
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CONTENTS
Page
ACKNOWLEDGMENTS xii
ABSTRACT xiii
SUMMARY 1
RECOMMENDATIONS 5
CHAPTER I. INTRODUCTION 6
Description of the Study Area 6
Developments Leading to the Study 7
Purpose and Scope of the Study 8
The Technical Studies Program 8
Summary 9
CHAPTER II. AIR POLLUTION POTENTIAL - METEOROLOGY 10
Topography 10
Climatology 10
Temperature 10
Precipitation 12
Wind 13
Atmospheric Stability 16
Normality of the Sampling Period 18
Temperature 18
Precipitation 18
Wind 19
Atmospheric Stability 20
Unusual Weather 21
Conclusion Regarding Normality 21
Summary 22
References 22
CHAPTER IE. SOURCES OF AIR POLLUTION 23
Industrial Operations 25
Sulfate (Kraft) Pulp Mill 26
Lumber Mills 39
Asphalt Plant 39
Other Industrial Operations 40
Fuel Usage 40
Natural Gas 40
Coal, Oil, and Presto Logs 41
Fuel Used in Motor Vehicles 44
Refuse Disposal 44
Summary 46
References 47
IX
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Page
CHAPTER IV. EVALUATION OF AIR QUALITY 49
Description of Sampling Stations 49
General Considerations 49
Atmospheric Particulate Matter 52
General 52
Results 52
Conclusions Regarding Particulates 60
Visibility 60
Methodology 61
Visibility in the Valley 62
Conclusions Regarding Visibility 71
Hydrogen Sulfide 71
Nature of the Gas 71
Area Concentrations 74
Seasonal Variations 75
Variation by Day of Week 76
Diurnal Variations 76
Relationship of H2S Concentrations to Weather
Parameters 78
Episodes During Study Period 82
Comparative Studies of Atmospheric H2S
Concentrations 88
Tape Fading 89
Conclusions Regarding ^S 91
Sulfur Dioxide 92
Conclusions Regarding SO2 93
Odors 94
General 94
Criteria for Odor Surveys 95
Methods of Odor Surveys 95
Methodology of This Odor Survey 95
Major Odor Problems 99
Odor Perception Versus Human Variables 101
Conclusions Regarding Odors 104
Summary 105
References 105
CHAPTER V. SOME EFFECTS OF AIR POLLUTION 108
Deterioration of Materials 108
Silver Tarnishing 108
Paint Blackening 117
Health and Welfare Implications 119
Summary 122
References 122
CHAPTER VI. PUBLIC AWARENESS AND CONCERN WITH
AIR POLLUTION 124
Introduction 124
Sources of Air Pollution 125
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Page
CHAPTER VI. (Continued)
Action to Reduce Air Pollution in Clarkston 125
Concern with Air Pollution in Relation to Demographic
and Social Characteristics of Clarkston Residents .... 126
Summary 128
CHAPTER VH. APPRAISAL AND SOLUTION 128
General 128
Evaluation 129
Solution to the Problem 130
The Air Resources Management Council 131
References 134
APPENDIX A. ANALYTICAL METHODS 135
High-Volume Samples 135
Total Suspended Particulates 135
Water-Soluble Sulfates 135
Sodium 135
Calcium 135
Hydrogen Sulfide 136
AISI Procedure 136
Colorimetric Method 136
Sulfides Damage in Paint and Silver Samples 137
References 137
Method of Test for Odor Sensitivity 137
APPENDIX B. CORRESPONDENCE 140
APPENDIX C. STATISTICAL ANALYSIS OF STUDENT ODOR
DATA 142
Area 142
Time 146
Human Variables 149
APPENDIX D. LEGAL BASIS FOR AIR POLLUTION CONTROL 151
Idaho 151
Specific Legislation to Control Air Pollution . . . 151
City Charter Provisions - Lewiston, Idaho 152
Washington 153
Specific Legislation to Control Air Pollution.... 153
City Ordinance - Clarkston, Washington 154
Federal Clean Air Act of December 17, 1963 154
xi
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ACKNOWLEDGMENTS
A survey of this size and scope, representing so many interests,
is possible only through the cooperation of many individuals and organi-
zations. Grateful appreciation is, therefore, extended to those whose
generous giving of time, effort, and facilities made this study possible;
to the individuals who aided in execution of the study and in preparation
of the report; to the 240 students of the high schools in Lewiston and
Clarkston who participated in the odor survey and the 6 instructors who
supervised the work and daily transmitted the data. Without their help
the survey could not have been accomplished. Our sincere thanks are
directed to the Washington Water Power Company of Clarkston, Wash-
ington, which provided laboratory facilities, working space, and per-
sonnel to assist in the sampling program.
We acknowledge the contributions made by Robert Roland,
Meteorologist in Charge, Weather Bureau Airport Station in Lewiston,
Idaho; and by Keith Stokes, the City Engineer of Moscow, Idaho, who
cooperated in locating and operating a control station there.
Finally, we express our sincere appreciation to the many resi-
dents of the two communities and their suburbs who gave freely of their
time to supply information and other assistance.
xn
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ABSTRACT
As a result of an increasing number of complaints from citizens
about reduced visibility, damage to house paint, tarnishing of silver,
undesirable odors, and suspected effects of air pollution on health, Idaho
and Washington and Lewiston and Clarkston officials requested assist-
ance from the U. S. Public Health Service. Subsequently, the Public
Health Service, the two states, and the two cities agreed to undertake
a cooperative study; the two cities participated in the study. The pur-
pose of the study was to determine the nature and extent of air pollution
in the two-city area and to assemble information to be used as a basis
for technical and official action needed to conserve air quality in the
area.
Because of its unique valley location, the two-city area is sus-
ceptible to meteorological conditions conducive to pollutant accumula-
tion. Either city can contaminate the other, and this creates a multi-
jurisdictional problem that requires joint and cooperative action to
control air pollution. As a first step to solve the problem, an Air
Resources Management Council consisting of county, city, and state
officials is to be organized. This council will be responsible for plan-
ning surveys and studies to determine air quality guides and legislation
and administration necessary to control air pollution in this multi-
jurisdictional area. The Public Health Service in its advisory capacity
will provide technical assistance.
Xlll
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SUMMARY
To comply with a request for assistance from officials of the City
of Clarkston, a cooperative interstate study of air pollution was con-
ducted in the communities of Lewiston, Idaho, and Clarkston, Washing-
ton, during the winter of 1961-1962. The request was motivated by
public complaints about reduced visibility, damage to house paint,
tarnishing of silver, undesirable odors, and suspected effects on health
resulting from air pollution. The kraft pulp mill located near Lewiston
about 2 miles east of Clarkston was cited as a major source of pollution.
The purpose of the joint study was to determine the nature and ex-
tent of air pollution in the two communities, and to assemble data and
information needed as a basis for remedial action. The study included
the following activities:
1. Analysis of past and current data on meteorology.
2. An emission inventory.
3. Measurement of atmospheric pollutants.
4. Measurement of visibility.
5. Assessment of ambient odors.
6. Measurement of materials deterioration.
7. Interview of local physicians concerning health effects.
8. A survey of public opinion.
The meteorological studies included a review of past climatological
and meteorological data, and observations of wind speed, wind direction,
temperature, and relative humidity at a station in the valley to supple-
ment concurrent data collected at the Lewiston airport.
The two communities are in a deep, narrow valley at the confluence
of the Snake and Clearwater Rivers. The climate is relatively mild,
compared with other sections of Idaho, but the cities frequently experi-
ence poor atmospheric ventilation owing to low wind speed and low-
level inversions. Actually, Lewiston seems to have the lowest average
annual wind speed of any city for which Weather Bureau records are
available. The predominant wind direction is from the east, particularly
at night. Stationary high-pressure systems conducive to air pollution
and lasting several days can be expected twice yearly. Low-level
inversions are most frequent in the fall, when they may be expected to
occur about 50 percent of the time.
Meteorological measurements during the sampling period showed
wind speeds higher and frequency of easterly winds lower than normal.
These factors tended to remove pollution from the area.
An estimate of major air contaminant emissions for the area was
made from information provided by the communities and industries in
the area. No stack sampling was done, and all estimates were based
on information from the literature and other sources.
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The major contributor of hydrogen sulfide and other malodorous
organic gases is the kraft pulp mill. In addition, the pulp mill contri-
butes about 77 percent of the estimated gaseous emissions and about
82 percent of the estimated particulate emissions. It also contributes
an estimated 4,640 tons of water vapor each day to the atmosphere.
This is thought to have a significant effect on the humidity in the
valley under certain meteorological conditions. The major gaseous
emission from the pulp mill is the "combustible" from three recovery
furnaces and three lime kilns. This combustible probably consists of
carbon monoxide and partially oxidized organic compounds.
The pulp mill has installed many control devices, but the recovery
furnaces and kilns may, from time to time, emit odorous compounds to
the atmosphere. A sulfate pulp mill also has innumerable small sources
of odor emission that in total constitute a difficult problem.
Emissions from other industrial operations are relatively small.
Home heating is the largest source of sulfur oxides, and transporta-
tion (gasoline engine exhaust) contributes a substantial amount of
carbon monoxide to the atmosphere. Refuse disposal is a relatively
minor source of air contamination on a weight basis, but the odor pro-
duced by burning garbage and refuse causes a local nuisance.
The evaluation of air quality included measurement of ambient
concentrations of hydrogen sulfide, sulfur dioxide, and suspended
particulate matter at five sampling stations in the Lewiston-Clarkston
area, and a control station in Moscow, Idaho. Paint and silver speci-
mens were exposed to measure deterioration caused by hydrogen sul-
fide and other sulfide compounds. Visual and photographic observations
were used to measure visibility reduction. Odor surveys were con-
ducted in the two communities in November and April.
Data on suspended particulate matter revealed both natural and
industrial sources of pollution. Sulfate and sodium contents of the
suspended particulates were significantly higher in the Lewiston-
Clarkston area than in Moscow, Idaho, a nearby non-industrial city of
comparable size.
Visibility reduction data, correlated with meteorological data, and
data on humidity and emissions of water vapor from the mill indicate
that a visibility problem exists. The presence of smoke most often
resulted from a combination of stable atmosphere with high relative
humidity and an easterly wind.
Hydrogen sulfide levels were significantly higher at sampling sites
in the valley. Concentrations were highest in November and February,
which were periods of higher frequency of inversions. Hydrogen sul-
fide levels in Moscow were consistently low and showed no diurnal
variation. Significant morning peaks occurred between 8 and 10 a.m.
at the two Clarkston stations, and between 10 and 12 noon in the Lewis-
ton commercial area. The time difference is due to the unique topo-
graphy of the study area. Two stagnant weather episodes, lasting 8
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
GPO 816-920—2
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and 10 hours, were observed in which hydrogen sulfide concentrations
exceeded 10 parts per billion.
Atmospheric sulfur dioxide was measured continuously over 2-week
periods in each of the months, November, January, and April. A total
of 512 2-hour samples were collected. The concentration range was
highest in January (range 0-25 ppb, average 4.7 ppb) during the coldest
period, indicating fuel burning for space heating as the primary source
of sulfur dioxide. Maximum daily concentrations occurred at 9 a.m.,
at the time of inversion breakup. Atmospheric contamination by SO2
is not currently a problem.
Odor surveys were made in November and in April with an
observer corps of approximately 100 high school students from the two
communities to determine odor types, intensities, and possible sources.
The students were first given odor sensitivity tests. Odor observations
were made three times daily at prescribed times. Each observer re-
ported any odor experienced and an estimate of its intensity. The
analyzed data show that pulp mill odors represent the largest single
nuisance odor category, affecting Lewiston most in November and
Clarkston most in April. The number of reports of burning leaves did
not vary significantly between areas. Odors of open trash burning were
reported frequently in the Clarkston area in November, indicating a
localized problem. Pulp mill odors were reported most frequently in
the morning. Odors from the burning of wood, leaves, and rubbish
were reported more frequently in the afternoon. There was no signifi-
cant difference between the two periods based on response to all odor
types. Pulp mill odors varied between November and April in the
Lewiston area.
Materials deterioration studies were conducted to show effects of
polluted air on white lead-based house paint and on silver plate. Paint
panels and silver plates were exposed on a scheduled basis during the
6-month study period and evaluated for deterioration by measurements
of the decrease in reflectance. Silver plates were also exposed at a
control station in Moscow, Idaho. Data from these tests showed
negligible silver tarnishing in MOSCOW. Silver plates exposed in the
valley were tarnished more than those exposed in the upland sites.
New plates were tarnished more during the first 30 days of exposure
than in the later part of the study. Lower levels of tarnish during
December and January correlate with lower levels of air pollution
during this period. The relative severity of tarnishing, as an indicator
of sulfide gases in the air, is greater in Lewiston than in Clarkston.
The results obtained from exposed paint samples were inconclusive.
Studies to provide precise data relating to health effects and
pollutant concentration were not made. Information obtained through
interviews of local physicians revealed that many believed local air
pollution was adversely affecting some of the townspeople.
The survey of public opinion concerning air pollution, conducted
in Clarkston during May 20-25, 1962, showed that approximately 81
Summary
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percent of the 104 persons interviewed believed that Clarkston had an
air pollution problem. About 66 percent indicated they were bothered
by it. Bad smells, frequent haze or smog, nose and throat irritation,
eye irritation, excessive dust and dirt were cited as the principal air
pollution phenomena. More than 90 percent of the respondents who re-
ported they were aware of air pollution named the pulp mill as respon-
sible. More than 33 percent of the people feel the need for official en-
actment of air pollution control measures. Air pollution in Clarkston
appears to constitute a community-wide problem. Concern appears to
be associated with civic pride and a desire to ameliorate the situation.
The study demonstrates the need for establishing a Regional Air
Resource Management Council and for establishing air quality goals,
as well as a program for air quality monitoring, for predicting adverse
episodes, and for controlling sources of pollution, such as the garbage
dump and specific factory emissions. The council would consist of
representatives designated by city, county, and state governments as
well as commercial and industrial establishments.
A program of action calls for the use of every opportunity to
resolve air pollution problems without resort to legal redress so long
as reasonable progress is evident as determined by the control council.
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
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RECOMMENDATIONS
In making these recommendations, the participating agencies
recognize that the protection of air resources is essential to human
well-being and orderly development of the area. Accordingly, it is
recommended that:
1. An Air Resource Management Council should be organized and
activated in 1964. The Council would consist of representatives
from appropriate county and municipal agencies and from each
of the respective state governments. The Public Health Service
would act in an advisory capacity.
2. The Council should develop a program that might include the
following:
(a) Establish an air quality monitoring network, including
meteorological instrumentation.
(b) Assist in the development of a plan to control emissions of
air pollutants at the sources.
(c) Arrange for personnel and other resources needed to imple-
ment the program.
(d) Determine the need for additional studies and arrange for
their implementation.
The manner, method, and time scheduled for accomplishing these
goals will be decided by local and state officials with the guidance of
the public and representatives of commercial and industrial interests
of the area.
3. The Council should release annual reports to permit evaluation
of progress and to engender continued support.
4. Every opportunity should be given to resolve air pollution prob-
lems in the area without resort to legal redress so long as
reasonable progress is evident as determined by the Council.
5. Local, city, and county governments should take steps to mini-
mize the air pollution problem from the burning of refuse by
individuals. Further, the City of Clarkston should eliminate the
open burning of municipal refuse.
* Agreed to by the participating Agencies at the conference held in Coeur d'Alene,
Idaho, July 6-10, 1963.
Recommendations
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CHAPTER I. INTRODUCTION
DESCRIPTION OF THE STUDY AREA
This report explores an air pollution situation unique in many
respects. A narrow, deep river valley impedes nature's attempts to
disperse and dilute emissions to the atmosphere. Interstate trans-
port of emissions occurs.
The twin cities of Lewiston and Clarkston are a major center of
commerce and trading for a population of over 100,000. Lewiston,
Idaho's first territorial capitol, now has a population of about 12,700.
Lewiston Orchards, unincorporated, adds approximately 10,000 to the
area. Clarkston has a population of about 7,000, with Clarkston Heights
adding more. Thus, about 30,000 people reside in the valley area.
The cities are located at the confluence of the Snake and Clear-
water Rivers at 738 feet above sea level, about 110 miles southeast of
Spokane, Washington. The area is set in a rather narrow valley
oriented east and west with a range of hills on the north sloping abrupt-
ly to about 2,000 feet above the valley floor. To the south the terrain
rises more gradually to a flat bench about 700 feet above the valley.
This area, at the lowest elevation in Idaho, has a very mild climate,
from which it gets its name, "the Banana Belt." Rainfall averages 13
inches annually. On the prairies surrounding the valley, winter temp-
eratures generally are much lower and precipitation almost double
that recorded in the valley.
The mildness of the winters, the long growing season, and the good
soil combine to make the area an important agricultural center. Wheat
is the principal crop, but near the cities abundant fruit and vegetable
crops are grown under irrigation. The biggest single business is
making forest products. Each of the cities has three or four lumber
mills. Lewiston is the home of Potlatch Forests, Inc., reputedly one
of the largest white pine pulp mills in the world. It is estimated that
one-third of the area's labor force is employed directly by this plant,
and another large portion of the population is indirectly dependent on
the mill.
The cities are preparing for a day when deep-draft barges will tie
up at their docks to carry the resources of North Central Idaho down
the Snake and Columbia Rivers to the markets of the world. Dams
under planning and construction on the lower Snake River soon will
make this a reality. The completion of the Lewis-Clark Highway also
linking the Pacific Coast with the area and opening opportunities for
travel and resources development to the east through Montana will
spur the growth of the area. Already new industrial sites are being
recommended for plants of all kinds.
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
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With growth have come air pollution problems and with further
growth will come additional problems unless steps are taken now to
initiate sound air resource management programs. Complaints of the
local citizens have increased in recent years. They cite the pulp and
paper mill in the Lewiston area as responsible for reduced visibility,
damage to house paint, tarnishing of silver products, undesirable odors,
and suspected effects on health. The mill owners have recognized their
responsibility to the communities and have attempted to be good neigh-
bors by spending thousands of dollars to reduce and prevent pollution.
Nevertheless, complaints continued and steps were taken by the local
citizens to obtain help in improving air quality.
DEVELOPMENTS LEADING TO THE STUDY
On November 4, 1960, Mr. Bill V. Courtney, then Mayor of Clarks-
ton, wrote to Mr> Vernon G. MacKenzie, Chief, Division of Air Pollution,
Public Health Service, requesting assistance in resolving an air pollu-
tion problem affecting both the Clarkston, Washington, and Lewiston,
Idaho, areas. The major source of air pollution was said to be the pulp
mill operated by Potlatch Forests, Inc., near Lewiston and about 2
miles east of Clarkston.
In response, the Public Health Service, through its regional offices,
communicated with the appropriate departments of the two state
governments. The purpose of this communication was to assemble
available information regarding the extent of the air pollution problem
and to determine what, if any, activities were intended for its solution.
The Public Health Service also offered to send an engineer from the
Division of Air Pollution to meet with the appropriate officials of each
state.
At the request of the Idaho Air Pollution Control Commission, Mr.
J. J. Scheuneman, Chief, Technical Assistance Branch, met with
officials of the Commission and the Idaho State Department of Health
in Boise on June 5, 1961. It was agreed that the Public Health Service
would prepare a draft of a proposal describing the air pollution studies
to be conducted on a cooperative basis with the Idaho Air Pollution
Control Commission, the Idaho State Department of Health, and the
local agencies in the Lewiston area.
A subsequent meeting was held with officials of the Washington
State Department of Health, and a similar agreement was reached.
On August 15, 1961, proposals were submitted to officials in both
Idaho and Washington for a cooperative air pollution study to be start-
ed in October 1961. As the various agencies agreed to proceed with
the study program, meetings were subsequently held in Lewiston, Idaho,
during the week of October 16. All the agencies concerned were
represented, and details of the program were reviewed. Agreement
was reached to start the studies during the week of October 23.
Introduction - Chapter I
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PURPOSE AND SCOPE OF THE STUDY
In view of the apparent official and public concern about air
pollution in the area and the complex jurisdiction needed to resolve the
problems, the Division of Air Pollution of the Public Health Service
entered into an agreement with the states of Idaho and Washington and
the cities of Lewiston and Clarkston to conduct a cooperative study to
determine the nature and extent of the air pollution and collect data and
information as a basis for technical and official action.
The survey was initiated during the week of October 23, 1961, with
the following general objectives:
1. To estimate the nature, extent, and effects of air pollution in the
area.
2. To sample the opinion of persons living in Lewiston and Clarks-
ton to determine: (1) the proportion of the population disturbed
by air pollution, (2) their geographic distribution, and (3) the
source and severity of the problem.
3. To recommend practical and reasonable measures for control
of air pollution in the area.
THE TECHNICAL STUDIES PROGRAM
The joint air pollution studies included the following major activi-
ties, each of which is discussed in detail in this report:
1. Meteorological observations were made of wind speed, wind
direction, temperature, and relative humidity at a station
located in the valley to supplement concurrent data collected at
the U. S. Weather Bureau Station at the Lewiston airport. The
data were used to evaluate the air pollution potential of the area,
to establish the normality of the sampling period, and to inter-
pret more objectively the air quality data obtained from the
study.
2. An emission inventory of all major sources of pollution in the
area gave estimates of the quality and quantity of contaminants
discharged into the ambient air from the various sources. Al-
though no stack sampling was conducted, emissions from
domestic, commercial, and industrial sources were calculated
from available data.
3. Analyses of air samples for hydrogen sulfide, sulfur dioxide,
suspended particulate matter, sodium, calcium, and sulfate
revealed the frequency of occurrence and the severity of
pollution levels. Correlations of air quality data with observa-
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
tions of weather and odor levels substantiated the findings of
the emission inventory regarding the major pollutants and their
sources.
4. Visibility reduction in the valley was studied by use of photo-
graphs, visibility observations, and evaluation of relative
humidity data with concomitant smoke observations by U. S.
Weather Bureau personnel.
5. Odor surveys carried out for 2 weeks each in November and
April determined the odor intensities, types, and probable
sources. Odors were evaluated by use of scentometers and by
use of high school student observers.
6. To determine the effect of atmospheric pollutants on paint and
silver, sample specimens were exposed and compared with
similar samples exposed in Moscow, Idaho. Laboratory tests
confirmed the presence of sulfides on the exposed surfaces of
silver plates.
7. A public opinion survey conducted in Clarkston reflected the
adult population's views concerning local air pollution, its
sources, severity, effects, and the means for control.
During this investigation the U. S. Public Health Service provided
technical equipment, supplies, and manpower. The States of Idaho and
Washington provided supplies and manpower; local agencies and other
personnel did much of the sample collecting and periodic equipment
servicing. The field aspects of the survey were concluded April 30,
1962. The preparation of an initial draft of this report was assigned
to the Public Health Service. Subsequent detailed comments by all
participating agents were incorporated, and are reflected in this final
joint report.
SUMMARY
To comply with the requests for assistance from city and state
officials, the U. S. Public Health Service entered into an agreement
with the States of Idaho and Washington and the cities of Lewiston,
Idaho, and Clarkston, Washington, to conduct a cooperative study of air
pollution in the Lewiston-Clarkston area. The Cities of Lewiston and
Clarkston participated in the project. The request was motivated by an
increasing number of complaints from citizens about reduced visibility,
damage to house paint, tarnishing of silver, undesirable odors, and
suspected effects of air pollution on health. The kraft pulp mill,
located near Lewiston and about 2 miles east of Clarkston, was cited
as a major source of pollution.
The purpose of the joint study was to determine the nature and
extent of air pollution in the two-city area, and to assemble data and
information as a basis for technical and official action needed to con-
Introduction - Chapter I
-------
serve air quality. The joint air pollution studies conducted November
1961 through April 1962 included the following major activities:
1. Analyses of past and current data on meteorology.
2. An emission inventory.
3. Measurement of atmospheric pollutants.
4. Measurement of visibility.
5. An odor survey.
6. Materials deterioration studies.
7. A public opinion survey.
CHAPTER II. AIR POLLUTION POTENTIAL -
METEOROLOGY
TOPOGRAPHY
Lewiston and Clarkston are in a Y-shaped valley where the Snake
River, flowing from the south, turns abruptly to the west and is joined
by the Clearwater River flowing from the east (Figure 2 -1). The east-
to-west portion of the valley is rather narrow, with a range of foothills
to the north sloping abruptly to about 2,000 feet above the river, which
at the city of Lewiston is about 700 feet above mean sea level. To the
south the terrain rises more gradually to a relatively flat bench, which
is east of the Snake River and about 700 feet above the valley floor.
Temperature
CLIMATOLOGY
1
Although Lewiston is at about the same latitude as Duluth,
Minnesota, the climate, especially in winter, is comparatively mild,
which is explained by its location with respect to Pacific air masses
and by the shelter provided by surrounding mountains.
Within relatively short distances from the valley, however, the
climate varies considerably. On the prairies surrounding the valley,
winter temperatures are much lower, and the precipitation is normally
almost double that recorded in the valley and at the airport.
Temperatures range from the highest recorded, 117°F, to the
lowest, -23°F, but during many winters a temperature of zero has not
been recorded in the valley. The summers are hot and dry with after-
noon temperatures of 100° or more continuing for as many as 10 days,
but there is considerable cooling after sunset.
The amount of pollution resulting from space heating is inversely
related to temperature. A commonly used measure of heating require-
ments is the degree-day value found by subtracting the mean daily
10 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
Sf
s?
o
o
I
-
Figure 2-1. Topogrophic mop of Lewiston, Idaho, and Clarkston, Washington, area.
-------
temperature in degrees from 65°F. If the mean temperature is 65°or
greater the degree-day value is 0. For example, if on a day, the maxi-
mum temperature is 49° and the minimum is 31°, giving a mean of 40°,
the degree-day value is 25. These values are summed over each month
of the heating season. The normal monthly degree-day values based on
30 years of data are shown in Figure 2-2, which indicates that the
heating season extends from September into June with heating require-
ments for December and January about 2.5 times those for October and
April.
1,200
; 1,000
600
400
200
\-
o
D J F
MONTH
Figure 2-2. Normal heating requirements for the
Lewiston-Clarkston area.
PRECIPITATION
Although precipitation is of minor importance in an assessment of
the air pollution potential of an area, it does remove air pollutants,
especially larger particulates, by washout.
For the study area precipitation usually amounts to about 13
inches annually, evenly distributed, except for July and August, when
there are infrequent thunderstorms that usually drop only small
amounts of rain. Snowfall in the valley averages about 18 inches dur-
12
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
ing the year, concentrated in December, January, and February, but in
the high country surrounding the valley the snowfall is much heavier.
WIND
Of perhaps the greatest importance to an assessment of the air
pollution potential of an area is the pattern of its winds, since the winds
transport pollutants from their sources and dilute them to lower con-
centrations. If reversals of flow occur, pollutants emitted from a
source may return to the vicinity of the source and result in increased
concentrations. Pollution is diluted downwind in direct proportion to
the wind speed. Low wind speeds that allow high pollutant concentra-
tions are, therefore, of special interest. Wind speeds and directions
are influenced greatly by topography and may be expected to differ at
different locations. To evaluate the winds in the study area, a com-
parison of 5 years of record at the airport (1957-1961) with 5 years of
record at the Post Office Building in downtown Lewiston (Dec. 1927 -
Nov. 1932) was made for the four seasons at the hours 0400, 1000, 1500,
and 1900. Simultaneous observations are not available since the Post
Office Station was closed in 1933. The airport is about 2 miles south of
Lewiston and 700 feet above the business section of the City. The wind
roses are shown in Figure 2-3.
Wind Speed
Figure 2-4, comparing the percent frequencies of winds between
0 and 3 mph for both locations, shows that the city location definitely
has a higher frequency of low winds and so cannot disperse pollutants
as effectively as the location near the top of the valley. Variation of
the speed frequencies with respect to time of day is greatest during
summer and least in winter. Low wind speeds are most frequent dur-
ing fall at the city location and during winter at the airport. Light winds
are generally most frequent at the hours 0400 and 1900 at both locations
and least frequent at 1500. The airport reported a much higher fre-
quency of calms. This resulted primarily from differences in the types
of instruments and the observational procedures; total miles of wind
passing each hour were recorded in 1927-1932 whereas 5-minute
average winds were read from an indicating dial for the 1957-1961
observations. In an attempt to eliminate the effects of these differences,
only the frequencies of winds from 0 to 3 mph have been compared.
Wind Direction
Wind direction varies considerably at various times of the day at
both locations. At 0400 at the airport, for all seasons, winds from the
east and southeast dominate. This probably results from a combination
of downvalley (easterly component) and downslope (southerly drainage
components) effects. Winds at this same time in the city are also pri-
marily easterly (downvalley), but have a secondary prominence of
northeasterly winds rather than southeasterly, especially in winter.
This is probably the result of downslope effects (northerly component)
from the north side of the valley, which is much higher and steeper than
Air Pollution Potential - Chapter II 13
-------
POST OFFICE >—(106
0400
1000
1500
1900
Figure 2-3. Wind direction frequencies, Lewiston, Idaho, based on 5 years of record —
Post Office Dec. 1927-Nov. 1932; Airport Jan. 1957-Dec. 1961.
the south side of the valley and would be expected, therefore, to develop
a stronger slope wind.
At 1000 at the airport, the predominant winds come from the north -
east except in winter, when flow is predominantly easterly. This
probably results from the combined effects of the beginning of upslope
winds (from the north) and the downvalley winds remaining from the
night. In the summer, secondary maxima from the northwest and north
occur indicating enough heating by 1000 in this season for an upvalley
component to begin. At this same hour in the city, flow is from the
east and northeast; probably a continuation of nighttime conditions. In
the summer more westerly and northwesterly winds occur as at the
airport, an indication of the beginning of upvalley now during the
warmest season.
14
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
1 UU
V
u
0-
-£ 80
e
CO
o
H-
0
UJ
UJ
0.
I/)
--REQUENCY OF WIND
IO **
3 O O
D POST OFFICE
| AIRPORT
—
-
-
i
r-i
i
i
~|
n —
—
r
0400 1000 1500 1900 0400 1000 1500 1900 0400 1000 1500 1900 0400 1000 1500 1900
DEC,,JAN,,FEB. MAR.,APR,,MAY JUNE, J ULY, AUG. SEPT., OCT., NOV.
Figure 2-4. Frequency of wind speeds from 0 to 3 mph for selected hours
in Lewiston, Idaho. Based on 5 years of record: Post Office, Dec. 1927 - Nov. 1932;
Airport, Jan, 1957 - Dec. 1961.
At 1500 at the airport, in all seasons except winter, predominant
winds are from the west and northwest, indicating upslope and upvalley
components. In the winter there is not sufficient solar heating to pro-
duce upvalley and upslope winds. Frontal passages are also most
frequent in winter. Winter winds at 1500 are slightly more easterly
with a lack of northerly winds and about equal distribution through
the west and south quadrants. The city location also has high fre-
quencies of west and northwest winds at 1500 during all seasons except
winter. During summer and fall some southwesterly winds also occur
at this hour, owing, perhaps, to upslope winds on the north slope of the
side of the valley caused by domination of circulation by strong solar
heating.
At 1900 at both locations, upslope and upvalley winds still occur
in summer, which results in dominant northwesterly winds. In the
other three seasons winds from south through west generally predomi-
nate, probably because of the combination of the onset of downslope
winds with the last of the upvalley flow. This southwesterly flow is
least in winter, since an upvalley flow from the west is never too
strongly established in winter. Spring and fall show almost a balance
between west and southwest winds and east and northeast winds, which
indicates, perhaps, the onset of downslope winds from the north slope
and downvalley drainage winds at least part of the time. Winter is
dominated by easterly winds with a secondary maximum at northeast,
which indicates that, by this hour in the winter, cooling is sufficient
for both downslope, from the north slope of the valley, and downvalley
winds.
Air Pollution Potential - Chapter II
15
-------
In summary, the predominant wind direction in the Lewiston-
Clarkston area is from the east with maxima from that direction during
the nighttime hours. Westerly winds are most frequent during after-
noon and early evening hours. Because of the steep north slope of the
valley, winds having northerly components due to cold-air drainage
effects from this slope are much more frequent in Lewiston-Clarkston
than are winds with southerly components.
ATMOSPHERIC STABILITY
The diffusion of pollutants in the atmosphere greatly depends upon
the stability of the atmosphere, especially the depth of vertical mixing
of pollutants.
High-pressure Areas
The existence of high-pressure areas with light winds limiting the
horizontal transport of air pollutants and subsidence inversions limit-
ing the vertical mixing of pollutants is important in the assessment of
any air pollution problem. Generally associated with high-pressure
systems are clear skies, which are conducive to the formation of sur-
face inversions caused by radiation cooling at night; these inversions
are rapidly eliminated during the morning hours by solar heating.
This rapid elimination of nocturnal radiation inversions is accompanied
by inversion breakup fumigation whereby elevated plumes of air
pollution are brought to the ground in relatively high concentrations for
periods of from half an hour to several hours. 2,3 Klein^ tabulated
the number of high-pressure centers within 5° latitude and 5° longitude
squares at 1230 Greenwich Meridian Time for each month for 40 years
of record. The relative frequency of high-pressure centers, without
regard to speed, for the different months of the year for the square in-
cluding Lewiston-Clarkston is shown in Figure 2-5. This indicates that
from October through February the area is influenced by high-pressure
areas almost twice as often as during the period March through
September. November, December, and January show the highest fre-
quencies of high pressure from all causes.
u
•z.
M J J
MONTH
Figure 2-5. Frequency of stagnating high-pressure
systems by month in the Lewiston, Idaho,
and Clarkston, Washington, area based
on 40 years of record.
16
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
When a region of high pressure becomes stationary or stagnates,
unusually high concentrations of air pollutants can build up. Holtzworth 5
indicates that stagnating high-pressure systems over the western United
States are most likely to occur during November and December and
estimates that, on the average, about two of these high-pressure systems
are likely to affect the Lewiston-Clarkston area each year. Past cases
that met the objective criteria and lasted 48 hours or longer during the
months of October through January for the years 1957 through 1961 have
been studied. 6 Table 2-1 lists the number in the Lewiston-Clarkston
area.
Table 2-1. NUMBER OF EPISODES OF POTENTIAL AIR
POLLUTION LASTING 48 HOURS OR LONGER IN
THE LEWISTON-CLARKSTON AREA
January
October
November
December
1957
1
1
1958
1
2
1959
2
1960
2
1961
1
1
1
A model situation of a stagnation episode over the western United
States occurred from November 6 through 10, 1959. A Canadian high
at the surface spread slowly across western United States and was 'held
intact by the warm ridge aloft. This case is unusual for the Lewiston-
Clarkston area because of the extended duration. Surface winds on
November 5, 1959, were already light, but on the November 6 and con-
tinuing through November 10 all conditions necessary for air pollution
prevailed. A study of meteorological data for the fall months of 1957
through 1961 shows this to be the only time that a case of air pollution
potential existed a full 5 days.
Inversions
Although no local observations have been made of temperature
change with height in the Lewiston-Clarfcston area, a general indica-
tion of the frequency in percent of inversions and/or isothermal layers
based at or below 500 feet above the station elevation is available from
Hosier. 1 These data indicate that the fall has the greatest number of
hours of inversion. A low-level inversion may be expected to occur
during half the hours in the fall.
Air Pollution Potential - Chapter II
17
-------
NORMALITY OF THE SAMPLING PERIOD
Temperature
Monthly temperatures during the sampling period are compared
with mean monthly normals in Table 2-2. The largest departure from
normal was during November, which was 4.1°F colder than normal.
Heating requirements during the sampling period are compared
with the 30-year normal in Table 2-3. Although heating requirements
were above normal in November and March, near normal in December,
and below normal for the other 3 months, the heating requirements for
the 6-month sampling period (4,634 degree-days) were very near
normal (4,654 degree-days).
Table 2-2. TEMPERATURES MEASURED AT
LEWISTON AIRPORT IN °F
Normal
Sampling period
1961
Nov.
40.1
36.0
Dec.
34.0
34.0
1962
Jan.
30.7
32.1
Feb.
35.9
37.5
Mar.
42.6
41.5
Apr.
50.8
53.5
Table 2-3. HEATING REQUIREMENTS AT LEWISTON
IN DEGREE-DAYS
Normala
Sampling"
1961
Nov.
747
847
Dec.
961
950
1962
Jan.
1,060
1,013
Feb.
815
764
Mar.
663
724
Apr.
408
336
a Total degree-days for normal period, 4,654.
b Total degree-days for sampling period, 4,634.
Precipitation
November and March had more than normal, December had near
normal, and the other 3 months had lower than normal precipitation
(Table 2-4). December had a greater than normal and the other
months had a near normal number of days with precipitation (Table
2-5). Consequently, it is not expected that the number of days with
18
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
GPO 816-920—3
-------
precipitation, except in January which had only 7, compared with the
expected number, 12, had any great influence upon the air pollution
levels in the Lewiston-Clarkston area.
Table 2-4. PRECIPITATION AT LEWISTON IN INCHES
Normal
Sampling period
1961
Nov.
1.35
2.14
Dec.
1.30
1.10
1962
Jan.
1.05
0.51
Feb.
1.00
0.76
Mar.
1.14
1.43
Apr.
1.14
0.43
Table 2-5. NUMBER OF DAYS WITH
PRECIPITATION 0.01 INCH OR MORE
Normal
Sampling period
1961
Nov.
10
10
Dec.
11
17
1962
Jan.
12
7
Feb.
10
8
Mar.
11
13
Apr.
9
6
WIND
Wind Speed
Figure 2-6 illustrates the percent frequency of winds from 0 to 3
mph at both the post office and the airport for four periods, each in-
cluding 3 observational hours at different times of day for January and
February (winter months) and for March and April (spring months) of
1962. This graph cannot be compared directly with Figure 2-4, which
is based on 5 years of record for the two stations, since the latter is
based on 1-hour periods and for 3 months instead of 2, but the fact that
the percents of these low wind speeds are considerably less than those
for the 5-year period indicates that there was a higher frequency of
wind speeds greater or equal to 4 mph during these 4 months and that
March and April were considerably windier than usual.
Wind Direction
Figure 2-7 shows wind roses for 3 successive hours for four periods
of the day for two seasons during the study, both at the post office and
the airport.
The months of January and February had higher frequencies of
winds from the northeast quadrant at the post office than would normally
Air Pollution Potential - Chapter II
19
-------
E
O
100
80
60
40
20
I I AIRPORT
•i POST OFFICE
5500 T__.
0600 I 100 1600 1900
January and February
0400 0900 1400 1700
0500 TOOO 1500 1800
0600 I lOO 1600 1900
March and April
Figure 2-6 Frequency of wind speeds 0 to 3 mph for selected hours
in Lewiston, Idaho, January and February and March and April 1962.
be expected. Winds at the airport during these 2 months seemed to
have increased frequencies from both the northwest and southwest
quadrants.
During March and April higher frequencies of westerly winds were
also noted, showing an increased frequency of west-southwest winds at
the post office and increased frequencies of west through northwest
winds at the airport.
ATMOSPHERIC STABILITY
Temperatures were compared from hygrothermograph records at
the post office and at the airport for the months of January through
April 1962. When the temperature at the post office was lower than or
equal to the temperature at the airport, atmospheric conditions for that
hour were estimated to be stable. The number of hours with stable
20
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
January and February
POST OFFICE AIRPORT
March and Apr! I
POST OFFICE / AIRPORT
7T*
Figure 2-7. Wind direction frequencies for selected hours,
Lewiston, Idaho, January-April 1962.
conditions was determined for each month. The monthly percentages
of hours with stable conditions were January, 28 percent; February,
27; March, 15; and April, 10.
UNUSUAL WEATHER
The snowstorm on November 23 through November 25, 1961, was
one of the heaviest November snowfalls on record. Record low temp-
eratures for the dates were set on February 24, 25, 26, and 27, 1962.
On April 24 a windstorm causing minor damage occurred. The peak
observed velocity at the airport, west-northwest 55 mph with gusts to
65, was observed at 1358 hours.
CONCLUSIONS REGARDING NORMALITY
From January through April 1962 (wind observations were avail-
able at both the post office and the airport), air pollution concentrations
could be expected to be less than during a normal January-through-April
Air Pollution Potential - Chapter II
21
-------
period, because of the higher than normal wind speeds and because of
the lower than normal frequency of easterly winds, which tend to move
pollutants from the major source toward Lewiston-Clarkston.
SUMMARY
Lewiston and Clarkston are in a Y-shaped river valley with a range
of foothills to the north sloping to above 2,000 feet above the river. The
local meteorological conditions are greatly influenced by topography.
Low wind speeds frequently occur, particularly during the early morn-
ing hours. The predominant wind direction is from the east with maxima
from that direction during the nighttime hours. Westerly winds are
most frequent during afternoon and early evening hours. High-pressure
areas with light winds limiting the horizontal transport of air pollutants
and subsidence inversions limiting the vertical mixing of air pollutants
can affect the region in all months, and stagnating highs lasting 48 hours
or longer are common in the months of October through January with
most likely occurrences in November. The fall season has the greatest
number of hours of inversion; a low-level inversion is expected to occur
during half the hours.
During the period of the interstate study, air pollution concentrations
could be expected to be less than during a normal January through April
period, because of the higher than normal wind speeds, and because of
the lower than normal frequency of easterly winds. Winds from an
easterly direction tend to move pollutants from the major source toward
Lewiston-Clarkston, thereby increasing air concentrations.
REFERENCES
1. U.S. Weather Bureau. Local climatological data with comparative
data, Annual Summary. U.S. Government Printing Office, Wash-
ington, B.C. 1961.
2. Bierly, E.W. and Hewson, E.W. Some restrictive meteorological
conditions to be considered in the design of stacks. J. Appl.
Meteorology, 1: 383-390. 1962.
3. Church, P.E. Dilution of waste stack gases in the atmosphere. Lid.
Eng. Chem., 41: 2753-6. 1949.
4. Klein, W.H. Principal tracks and mean frequencies of cyclones
and anticyclones in the northern hemisphere. U.S. Weather Bureau,
Research Paper No. 40. Washington, D.C. 1957.
5. Holtzworth, G.C. A study of air pollution potential for the western
United States. J. Appl. Meteorology, 1: 366-382. 1962.
6. Miller, M.E. Personal communication. 1962.
7. Hosier, C.R. Low-level inversion frequency in the contiguous
United States. Mon. Wea. Rev., 89: 319-339. 1961.
22 Am POLLUTION IN LEWISTON-CLARKSTON AREA
-------
CHAPTER III. SOURCES OF AIR POLLUTION
An inventory of emissions was made for the Lewiston-Clarkston
area with information provided by the two communities and the industries
of the area. This inventory is as close an estimation of emissions as
was possible with available data and is useful in indicating the relative
importance of various sources of air pollution.
These sources of pollution have been divided into: kraft mill,
other industries, fuel usage, and refuse disposal. Each is discussed in
detail with a list of assumptions used in estimating emissions. The
total emission estimate is presented in Table 3-1.
The operations of the kraft mill emit hydrogen sulfide (I^S) and
other malodorous organic gases to the atmosphere. The odor potentials
of these materials are delineated below. 1
Approximate minimum
Substance and formula perceptible concentration, ppb
Hydrogen sulfide (H2S) 1
Methyl mercaptan (CH3SH) 1
Dimethyl sulfide (CHsSCHs) 10
Dimethyl disulfide (CH3SSCH3) 10
The difficulty of odor control becomes apparent from these
threshold odor data. The problem is further accentuated by the many
possible points of emission. Of the total estimated emissions listed in
Table 3-1, the kraft mill contributes about 77 percent of gaseous emis-
sions and about 82 percent of the solid particulate emissions. The
kraft mill data indicate that the major gaseous emissions are "com-
bustibles" discharged from the recovery furnaces and lime kilns. Com-
paring recovery furnace emission data supplied by the kraft mill and
information in published articles 2?3,4,5 resulted in the assumption
that the recovery furnaces were, from an air pollution standpoint, either
overloaded or inefficiently operated; however, recent information from
Potlatch Forests, Inc. states that the three recovery furnaces have "a
total capacity of 2,244,000 pounds of black liquor solids per day." 6
On the basis of 2,800 pounds of black liquor solids per ton of pulp pro-
duced, the furnaces are capable of handling a pulp production of 800
tons per day, i.e., 150 tons per day in excess of the operating rate dur-
ing the aerometric study. Potlatch further reports 6 recent changes in
the operation of the recovery furnaces wherein the oxygen content of the
flue gases has been increased two- to threefold. These changes should
effect a reduction in the emission of odorous sulfur compounds from the
recovery furnaces.
Sources of Air Pollution - Chapter IE 23
-------
Table 3-1. TOTAL ESTIMATED AIR CONTAMINANT EMISSIONS
IN THE LEWISTON-CLARKSTON AREA (Ib/day)
Pollutants
Sulfur oxides
Nitrogen oxides
Hydrocarbons
Aldehydes
Organic acids
"Combustible"
(as CO)
Ammonia
Hydrogen sulfide
Methyl mercaptan
Dimethyl sulfide
Other organic
gases
Total gaseous
pollutants
Total
particulate
matter0
Industrial
Potlatch
Forest
Inc.
1,214
3,757
1,285
149
112
289,100a
4,256
89
110
300,072
20,076
Other
21
198
2,625
236
54
Neg
-
Neg
3,134
2,057
Domestic-commercial
Heating
4,026
2,961
2,116
210
Neg
Neg
Neg
Neg
9,313
1,774
Refuse
disposal
68
90
135
225
Neg
904b
181
1,603
496
Trans-
portation
155
2,207
6,619
111
46
65,800b
44
74,982
12
Total
5,484
9,213
12,780
931
212
355,804
44
4,256
89
110
181
389,104
24,415
a Combustible emission from lime kilns and recovery furnaces consist of
carbon monoxide and organics.
b Carbon monoxide.
c Include solids from industrial operation.
Large quantities of water vapor are also emitted from the kraft
mill; these may have adverse effects on visibility in the valley under
certain meteorological conditions. It has been found to be feasible in
parts of Europe to extract heat from the emissions from paper ma-
chines and pulp driers, ">° thus reducing water emitted, but the
economic feasibility of such practice in this country was not determined
during this study.
Hydrocarbons and particulates are the major emissions from in-
dustrial operations other than the kraft mill, but these sources are
relatively small and of lesser importance to the community as a whole.
Home heating is a substantial source of sulfur and nitrogen oxides,
24
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
hydrocarbons, and particulate matter. Transportation is a major con-
tributor of hydrocarbons and a substantial amount of carbon monoxide
to the air. Emissions from fuel usage are so distributed over the com-
munity that large concentrations in any one area are uncommon.
Refuse disposal is a relatively minor source of air pollutants,
though the odor produced by burning garbage and refuse cannot be neg-
lected. Periodic local complaints of odor and smoke from refuse burn-
ing might be expected, but this source does not constitute a problem for
the area as a whole.
INDUSTRIAL OPERATIONS
Employment figures for Nez Perce County, which include Lewiston,
Idaho, are presented in Tables 3-2 and 3-3. The largest single indus-
trial category is obviously the lumber industry. In this area alone,
over 250 million board feet of lumber are produced annually, over and
above the output of the PFI pulp mill. Food processing and construction
are other major industries.
Table 3-2. NUMBER OF NEZ PERCE COUNTY EMPLOYERS
IN 1959 BY BUSINESS CLASSIFICATION a
Mining 6
Construction 81
Manufacturing 56
Transportation, communication,
utilities 36
Trade
Wholesale
Retail
Financial institutions
Services
Business
Professional
Other employment
47
254
53
99
95
5
Total 1959 employers 732
a Nonagricultural employers of one or
more reporting to Idaho Employment
Security Agency.
Sources of Air Pollution - Chapter HI 25
-------
Table 3-3. AVERAGE 1959 NEZ PERCE COUNTY
NONAGRICULTURAL EMPLOYMENT
AND PAYROLL a
Mining 16
Construction 279
Food produce 305
Lumber 1,820
Other 934
Transportation, communication,
utilities 441
Wholesale, retail trade 2,031
Finance institutions, real estate 266
Services, etc. 852
Average totals b 6,944
Total payrolls covered by Employment
Security Agency (thousands) $31,078
a Includes only those covered by Employment
Security Law.
b Totals include state employes not previously under
Employment Security Law.
SULFATE (KRAFT) PULP MILL
Process Description
The pulp mill in Lewiston, Idaho, produces 450 tons per day of
bleached paperboard and an additional 200 tons per day of market pulp
by the kraft process. Simplified flow diagrams of the mill showing
points of major pollutant emissions are given in Figures 3-1 and 3-2.
After the logs are stripped of bark, sawed, and chipped, the chips
are charged into the digesters and cooked for approximately 3 hours in
a solution containing sodium sulfide and sodium hydroxide. During
this time, sufficient live steam is injected to reach and maintain a
pressure of 110 psia. As steam is added, the gases are driven off as
relief gases and are treated by a cyclone separator that removes
small quantities of wood chips and cooking-liquor carryover. At the
end of the cook, the chips and spent black liquor are transferred into
"blow" tanks by steam pressure in the digesters. As the charge under-
goes a decrease in pressure, further steam is generated in the blow
tanks. This steam or "blow gas" is used to heat water for the pulp
washing process. Untreated blow and relief gases can be one of the
26 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
a
to
D)
>
r-"
4
o
O
I
0)
Adapted from a flow sheet by J. H. Gruber, P.F.I.
Major water vapor emissions
Figure 3-1. Flow diagram of sulfate pulp mill papermaking process.
-------
to
CD
o
t-1
§
CO
H
O
3
Adapted from a flow sheet by J.H. Gruber, P.F.I.
EMISSIOH KEY; [ './\lV'JSOLIDS (( \ W OMPS ( 0 ) H'STS /W\ WATER VAPOR
THE SIZE OF THE CIRCLE INDICATES THE RELATIVE MAGNITUDE OF THE SOUSCE
Figure 3-2. Process flow sheet showing sulfate pulp mill chemical recovery system and points of pollutant emissions.
-------
major sources of odorous gases in the kraft pulp mill.
The pulp and black liquor are next pumped from a blow tank to a
deknotter where the fibers and liquor are separated. From the dek-
notter the liquor is pumped to storage for further treatment in a
chemical recovery system, and the pulp is sent through a series of
either vacuum or pressure washers. In the vacuum system, the stock
is washed with water and then somewhat dehydrated by a vacuum main-
tained throughout the washer series. The pressure system also dilutes
the pulp, but removes water by squeezing the stock in an auger-type
pressure apparatus. The washed pulp is then thickened by further re-
moval of water and made ready for the bleaching process. The thickened
pulp is run through a chlorinator tank, caustic izer tank, and sodium
hypochlorite tank to destroy dyes formed from tannins present in the
wood. The bleached stock is next refined to a consistency specified by
the customer. The refined stock is then moved onto a screen and formed
into a sheet. Finally, the sheet is run through a Fourdrinier machine,
dried, rolled, and shipped to market.
Returning to the black liquor storage tank, the solution is now
ready for the chemical recovery cycle (Figure 3-2).
At this point, the liquor consists of a mixture of water, sodium-
lignin salts, sodium sulfide, and appreciable amounts of organic sulfur
compounds. The total solids content is about 15 percent. A small
portion of the liquor is diverted back to the digester for an incoming
cook, and the remainder is sent through one of three oxidation towers.
The function of the tower is to oxidize the organic sulfur compounds
and "fix" them into the solution to eliminate odors that would otherwise
evolve from the evaporators.
Leaving the towers, the liquor is sent through one of three sets of
multiple-effect evaporators where the black liquor is concentrated
from 15 to 50 percent solids.
Next, the liquor is put through a disc evaporator employing hot
gases at 550°F produced in the recovery furnace to concentrate the
solution further to 65 percent solids. As the solution leaves the evap-
orator, salt cake (^2804) is added to it to make up chemical losses,
and then the liquor is sprayed into one of three recovery furnaces.
Within the furnaces, reducing conditions are maintained by limiting
the amount of air admitted. Such an atmosphere results in the reduction
of sodium sulfate to sodium sulfide, which is the desired product for
later use in the digester cooking liquor. The smelt that runs from the
base of the recovery furnace consists primarily of sodium sulfide and
sodium carbonate, the latter being a product of sodium organic salt
combustion occurring in the furnace.
The smelt is dissolved in water in the dissolving tank to produce
what is called green liquor. The green liquor is clarified in a settling
tank, and the suspended solids are drained out, washed, and sewered.
Sources of Air Pollution - Chapter III 29
-------
The clarified green liquor is then sent to a slaker where lime is added.
The lime reacts with the sodium carbonate in the green liquor to
form sodium hydroxide and precipitate calcium carbonate. The causti-
cized solution is clarified to remove calcium carbonate and other sus-
pended solids. The resulting solution, called "white liquor," is pumped
to storage for reuse in the digester cooking process.
The settled solids, called lime mud, that emerge from the bottom
of the clarifier consist primarily of calcium carbonate and sodium com-
pounds. The sludge is moved through a mud washer where it is diluted
with a large quantity of water to recover the soluble sodium salts. The
settled mud is then run through a sludge filter and charged to one of
three rotary lime kilns for ignition. Here, the calcium carbonate is
converted to lime for later use in causticizing the green liquor.
Emission Sources
Obnoxious odors associated with the kraft process are attributable
to sodium sulfide in the cooking liquor. Although the chemistry involv-
ing the dissolution of noncellulosic portions of the wood is not completely
understood, the use of sodium sulfide in the cooking liquor hastens the
kinetics of the reaction by approximately 20 percent.
During the 3- to 8-hour cook, the sulfide ion reacts with hydrogen
and wood organics to form hydrogen sulfide (H2S), and organic sulfides
such as methyl mercaptan (CHsSH), dimenthyl sulfide (CHsSCHs), and
dimethyl disulfide (CH3SSCH3). Although volatile sulfur emissions may
be fairly low in a highly controlled plant, an odor nuisance may occur
because each of the above contaminants is, in itself, capable of produc-
ing a disagreeable odor at a concentration of less than 1 ppm. In parti-
cular, the lighter mercaptans have an extremely disagreeable odor at
very small concentrations.
Major sources of air pollutants are:
1. Solid emissions
a. recovery furnace
b. lime kilns
c. boiler plant
2. Odorous gases
a. recovery furnace
b. digester relief and blow gases
c. lime kiln
d. evaporators
e. boiler plant
3. Mists
a. recovery furnace
b. smelt tank
c. lime kiln
d. causticizer
e. digester
f. blow tank
30 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
There are also many other minor sources of emissions from the
chemical recovery system.
Emissions from Digester Relief and Blow Gas Systems
Malodors associated with the blow system are carried by the relief
and blow gases released during the cooking cycle. Control equipment
used to reduce these emissions is shown in Figure 3-2. Relief gases
are first run through a cyclone separator that removes small quantities
of entrained wood chips and cooking liquor and are then sent to a con-
denser. The condensate and remaining gases are next run to an ac-
cumulator tank for chlorination treatment. Blow gases evolving from
the pressurized removal of the pulp from the digester to the blow tanks
are partially condensed in a heat recovery system and then passed to
the same accumulator tank.
Wash water containing chlorine gas from the chlorination tower is
sprayed into the accumulator tank. Water-soluble gases are directly
washed into solution, and chlorine gas oxidizes the odorous materials
in the gases. Finally, the noncondensable gases are vented to the at-
mosphere.
Emission factors for sulfur compounds in the digester gases were
estimated by use of the data of DeHaas and Hansen9 and are given in
Table 3-4. The chlorination treatment of the digester gases and con-
densate is reported to be effective in reducing odorous emissions if the
proper amounts of chlorine are used. If an efficiency of 98 percent is
assumed, the sulfur compounds emitted are approximately as shown in
Table 3-5. These estimates indicate that H2S emissions may be insig-
nificant, but that the possibility exists for an odor problem from the
and CH3SCH3 emissions.
Table 3-4. EMISSIONS FACTORS FOR DIGESTER GASES a
Digester cooking
conditions
Cook time - 3.45 hr
Temperature - 172°C
Sulfidity - 22.5%
Pollutants per ton of pulp produced, Ib
Hydrogen
sulfide
0.66
Methyl
mercaptan
5.3
Dimethyl
sulfide
3.8
a Reference 9.
Sources of Air Pollution - Chapter HI
31
-------
Table 3-5. ESTIMATED EMISSIONS FROM ACCUMULATOR TANK
Entering accumulator
tank, Ib/day
Assumed efficiency of
chlorination, %
Leaving accumulator in
vent gas, Ib/day
Gaseous pollutant
H2S
430
98
8.6
CH2SH
3,460
98
69.0
CH3SCH3
2,470
98
50.0
Emissions from Recovery Furnace
The function of the recovery furnace is to reduce the sodium sulfate
present in the black liquor to sodium sulfide for later use in the cooking
cycle. To accomplish this, a reducing atmosphere is maintained within
the "primary reaction zone" by limiting the amount of combustion air
admitted. Reducing conditions are, however, favorable for the formation
of H2S as well as other organic sulfides.
Introduction of secondary air higher in the furnace chamber has
proved effective for the oxidation of H2S to SO2. Within this reaction
zone, oxidizing conditions are maintained by admitting additional com-
bustion air. H2S emissions as a function of oxygen composition of stack
gases are shown in Figure 3-3, together with the oxygen content of flue
gases from the three recovery furnaces at Potlatch Forests, Incor--
porated (PFI).
Each of the three furnaces is individually vented to the atmosphere
after treatment by a separate control device. Furnaces 1 and 2 are
vented to Cottrell electrostatic precipitators with flyash removal effi-
ciencies of 83 and 88 percent respectively. Furnace 3 is controlled by
a venturi scrubber with about an 80 percent efficiency. These values
are somewhat lower than efficiencies reported in the literature for
similar installations. 2,5,10,11
Flyash and H2S concentrations prior to treatment and final emissions
afterward are reported for each of the flue gas streams (Table 3-6). Of
the control devices, probably only the venturi scrubber effects H2S
removal. A study of Table 3-6 reveals the recovery furnace to be the
predominant source of flyash and H2S.
Methods that can be used to reduce H2S emissions from recovery
furnaces include introduction of adequate secondary combustion air and
the scrubbing of the flue gases with white liquor. Figure 3-3 indicates
that an oxygen content of 2 to 3 percent in furnace flue gas can permit
oxidation of H2S and other sulfur compounds to the less odorous SO2-
It should be noted, however, that the mere presence of excess oxygen in
32
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
1 2
02 IN FLUE GAS, %
Figure 3-3. Percent oxygen in flue gas vs. odorous
sulfur compound emission (Reference 9).
the effluent gases does not ensure combustion of odorous gases if the
secondary air is not properly mixed with the gases to be burned.
The result of oxygen deficiencies in the three recovery furnaces is
readily apparent by the amount of the combustible emission shown in
Table 3-6. This emission was calculated on the basis of data supplied
by the kraft mill. It was assumed that about half of this material is
carbon monoxide and that the remainder consists of organic compounds.
Recent information^ from the kraft mill is quoted as follows: "The
data provided to the U.S.P.H.S. indicated an oxygen content of 0% for
No. 1 recovery boiler and 1.2% for Nos. 2 and 3 recovery boilers. These
figures are believed to be reasonably correct at that time. However,
Potlatch is presently trying to operate the recovery boilers with 2-3%
excess oxygen consistent with recent industry trends and techniques.
Examination of records for the past two months indicate the following:
Recovery boiler
No. 1
No. 2
No. 3
Excess oxygen,
0.4 to 4.0
0.0 to 2.0
0.5 to 1.5
Sources of Air Pollution - Chapter III
33
-------
"The wide range of values reported above have been due, in part, to
operational difficulties which have been rectified during the 1963
Christmas shut-down."
On the basis of this new information, the emission of odorous sulfur
compounds from the recovery furnaces should be reduced.
Emissions from Evaporators
The innovation of black liquor oxidation treatment constitutes the
most effective measure yet taken by the industry to eliminate odors
evolving from a single process step. Thus, a discussion of odorous
emissions from the evaporators relates directly to the oxidizing effi-
ciencies of the oxidation towers. The efficiency of the three oxidation
towers at the kraft mill is reported to be 50 percent; thus, the odor-
reducing potential of this equipment is not fully realized.
Table 3-6. ESTIMATE OF GASEOUS AND SOLID EMISSIONS
FROM THE RECOVERY FURNACES
Item
Particulate generated,
Ib/day
Particulate control
equipment
Control equipment
efficiency, %
Particulate emitted,
Ib/day
"Combustible" emitted,
Ib/day a
Hydrogen sulfide emitted,
Ib/day
Sulfur dioxide,
Ib/day b
Furnace number
1
14,100
Electrostatic
precipitator
83
2,390
34,400
2,000
220
2
38,000
Electrostatic
precipitator
88
4,550
72,600
1,000
560
3
27,200
Venturi
scrubber
80.4
5,370
34,400
120C
400
Total
79,300
-
-
12,310
141,400
3,120
1,180
a "Combustible" consists of carbon monoxide and organic material.
b Assumed 30 ppm in flue gases of furnaces.
c Assumed 80 percent removal of H2S.
34
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
GPO 81 6—920—4
-------
K unoxidized black liquor is fed into the evaporators, the resulting
vapor phase is highly concentrated with E^S and CH3SH. Bergstrom and
Trobeck 12 have investigated these losses, and their results are reported
in Table 3-7, along with the estimated emissions from this source.
Table 3-7. ESTIMATED EMISSIONS FROM EVAPORATORS a
Emission factor, Ib/ton of pulp
Potential emission, Ib/day
Oxidation tower efficiency, %
Estimated emission, Ib/day
Pollutant
Hydrogen sulfide
1.2
780
50 b
390
Methyl mercaptan
0.06
40
50 b
20
a Reference 12.
b Communication from Idaho Department of Health, Sept. 24, 1962.
Emissions from Oxidation Towers
In a properly operated black liquor oxidation tower, a significant
emission of H2S or CH3SH is not likely but CH3SSCH3 and CH3SCH3 may
be present. For this inventory, it was assumed that the effluent from
each oxidation tower contained 1 ppm of CH3SCH3, ^ which totals
approximately 60 pounds per day. Odorous gases from this source can
be controlled by chlorination in a manner similar to that employed for
digester relief and blow gases.
Emissions from Lime Kilns
The calculated emissions from the lime kilns are given in Table
3-8. The particulate and combustible emissions are based on data re-
ported by PFI. The particulate or dust emission of 6,269 pounds per
day could be an important contributor to a localized air pollution prob-
lem.
Again it is noted that the emission of "combustibles" is excessive.
This combustible material is probably about half carbon monoxide and
the remainder organics. On the assumption that each kiln exhaust con-
tains 100 ppm H2S, it is seen that the 730 pounds per day emission could
significantly contribute to an odor problem. As with the recovery
furnaces, the proper use of adequate combustion air can reduce H2S and
other combustible emissions.
Sources of Air Pollution - Chapter III
35
-------
Calculations of other contaminant emissions, nitrogen oxides, alde-
hydes, and organic acid were based on the amount of natural gas fired
in the kilns.
Table 3-8. ESTIMATED EMISSIONS FROM LIME KILNS
Particulate matter
Total combustible a
Hydrogen sulfide
Sulfur oxides as SO2
Nitrogen oxides as NO%
Aldehydes as formaldehyde
Organic acid, as HAc
Emission, Ib/day
Kiln No. 1
724
15,700
137
Kiln No. 2
1,105
17,000
148
6
847
8
20
Kiln No. 3
4,440
115,000
452
Total
6,269
147,700
737
6
847
8
20
Combustible emission probably consists of carbon monoxide and
organics.
Emissions from Dissolving Tanks
The hot smelt that enters the dissolving tanks from the recovery
furnaces tends to shatter and results in the emission of mists and solid
particulates. This emission was estimated to be 17 pounds per ton of
pulp. 14 Each dissolving tank is equipped with a mesh demister assumed
to be 90 percent efficient. On this basis, total particulate discharge to
the atmosphere was calculated to be 1,100 pounds per day.
There is also the possibility of odorous emissions from these tanks,
but it was not feasible to attempt an estimate.
Emissions of Water Vapor
Water vapor can be considered an air pollutant because of its con-
tribution to the reduction in visibility. It is conceivable that large water
vapor emissions could combine with particulate material to cause more
and longer lasting fogs than would be ordininarily expected.
In the manufacture of pulp and paper, large quantities of water are
essential for pulp washing, dilution and transport, steam generation,
cooling, and numerous other uses. The kraft mill requires an average
of 40 million gallons of water each day, most of which is returned to
36
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
the river. Of this total water requirement, more than 2 percent is lost
to the atmosphere. Major sources of water vapor emission are the
recovery furnaces, lime kilns, paper machines, pulp dryer, and com-
bustion of fuels. The total water vapor emission is estimated to be
about 4,640 tons per day (Table 3-9). This amount of water vapor, from
essentially a point source, is equivalent to about 25 percent of the water
vapor generated by the combustion of all types of fuel in the entire
Lewiston-Clarkston area during the heating season.
Humidity data taken during this study, when compared with data
from 1924 to 1933, show that a significant increase has occurred (see
Table 4-6, p. 67). Water vapor emission from PFI undoubtedly increases
humidity in the valley atmosphere under certain meteorological con-
ditions.
Table 3-9. ESTIMATED WATER VAPOR EMISSIONS
FROM THE PULP MILL
Source
Recovery furnaces
Lime kilns
Paper machines
Pulp dryer
Boilers (gas fired)
Total
Water vapor emitted
Tons/day
1,389
925
891
160
1,275
4,640
Gal/day
333,000
222,000
214,000
38,400
306,000
1,113,400
Emissions from Mill Boilers
It was assumed that all boilers were gas fired; their emissions are
tabulated in Table 3-10. When these boilers are oil fired, the emissions
of particulates, nitrogen oxides, etc., increase substantially.
Summary of Emissions from Kraft Pulp Mill
Since no stack gas analyses were made at the kraft mill, the emis-
sions reported in previous sections and summarized in Table 3-10 are
estimates. The basis for these estimates was information provided by
the mill and a literature review. The emission estimates are not to be
construed as absolute values and are deemed useful only in showing the
relative importance of various air pollutant sources. Not included in
this report are estimates of emissions from storage tanks, leaks, hold-
Sources of Air Pollution - Chapter HI
37
-------
CO
00
Table 3-10. SUMMARY OF ESTIMATED EMISSIONS FROM KRAFT PULP MILL
o
f
5
o
£
CO
H
O
Process or
equipment
source
Digester gases
Evaporators
Recovery furnaces
Smelt tanks
Lime kilns
Oxidation towers
Plant boilers d
Paper machines
Pulp dryer
Total
Emissions, Ib/day
Hydrogen
sulfide
9
390
3,120
c
737
c
;
-
4,256
Methyl
mercaptan
69
20
neg.
c
c
c
;
-
89
Dimethyl
sulfide
50
neg.
neg.
c
c
60
;
-
110
Solid par-
ticulates
-
-
12,310
1,100
6,269
-
397
-
20,076
Combus-
tibles a
-
-
141,400
-
147,700
-
neg.
-
289,100
Sulfur
oxides
as S02
-
-
1,180
-
6b
-
28 b
-
1,214
Nitrogen
oxides
as NO2
-
-
c
-
847
-
2,910
-
3,757
Aldehydes
as form-
aldehydes
-
-
-
-
8
-
141
-
149
Organic
acids
as HAc
-
-
-
-
20
-
92
-
112
Hydro-
carbons
-
-
-
-
-
-
1,285
-
1,285
Water
vapor
-
-
2,778,000
-
1,850,000
-
2,550,000
1,782,000
320,000
9,280,000
a Combustible emission probably consists of carbon monoxide and other organic materials.
fc Assumed sulfur content of natural gas, 0.4 grain/100 ft3
c Indicated pollutant present in emissions, but amount is unknown.
d Emissions include those from burning waste wood.
to
M
-------
ing ponds, and other minor sources although the emission from each
source may be small, the total may be significant because many of the
gases involved have low odor thresholds.
LUMBER MILLS
The largest industry in the area is the manufacture of lumber and
wood products. The area has a total lumber production in excess of 250
million board feet per year as well as a 650-ton-per-day pulping oper-
ation. In all there are seven or eight lumber plants in addition to PFI,
which conducts the largest lumbering operation in the area.
The waste produced from a log is about 50 percent of the original
log; 15 more specifically, 10 percent is bark, 20 percent slabs, edging,
and trimmings, and 20 percent shavings and sawdust.
For plants as large as PFI, the use of shavings and sawdust to make
presto logs and the use of bark to make soil conditioner are profitable
ways to dispose of these byproducts. Smaller lumbering mills normally
burn their waste in large furnaces called Tepee burners. Some of the
shavings are sold for bedding for cattle and some sawdust is sold for
composting, but most of the waste is burned.
To estimate emissions from wood waste burning, an average density
of 27 pounds per cubic foot 16 was assumed for the waste wood. On the
basis of 1/12 cubic foot per board foot, the total weight of lumber pro-
duced per year was calculated. It was assumed that PFI used all shav-
ings and sawdust to make presto logs, that all slabs, edgings, and trim-
mings were made into wood pulp, and that 50 percent of the bark was
made into soil conditioner and the other 50 percent burned as waste. The
remaining lumber mills in the area produce approximately 50 million
board feet, or 20 percent of the total lumber produced. For saw mills it
was assumed that sawdust and shavings were sold for bedding and
composting. The remaining 30 percent, consisting of bark and slabs,
was burned. For planing mills, it was assumed that 50 percent of all
shavings and sawdust was sold and 50 percent was burned.
With the above assumptions, a total of 128,500 pounds per day was
burned by PFI and a total of 262,500 pounds per day by the other lumber
operations.
Emission factors were taken from the literature. 17 The computed
emissions from wood waste burning show hydrocarbons and particulate
matter to be the major pollutants (Table 3-11). Although wood waste
burning can be considered a relatively minor source in the area, local-
ized problems from smoke or wood particles may arise.
ASPHALT PLANT
One asphalt and gravel plant was reported in the area. This plant
handles large quantities of gravel in drying and mixing operations and is
a possible source of dust and smoke. The plant operates for 8 months
Sources of Air Pollution - Chapter HI 39
-------
each year, during which time approximately 56 thousand tons of gravel
are processed.
Assumptions were made concerning the efficiency of the control
equipment used by the plant, and the exhaust gases were assumed to con-
tain 4 grains of dust per cubic foot at a temperature of 350°F. 1° On
this basis, calculated dust emissions from the plant indicate that 1,712
pounds of dust is emitted to the atmosphere per working day. This dust
is rather fine, with 76 percent of the particles less than 5 microns in
diameter. This can cause a nuisance to receptors in the local area and
contributes to reduction in visibility.
OTHER INDUSTRIAL OPERATIONS
In addition to the industrial processes already described, there are
also stockyards, feed and grain mills, meat packing, and other miscel-
laneous operations. Information was not available to make estimates of
emissions. It can be said in general that the total pollutants from such
operations will be relatively small, but that the potential exists for
localized dust and odor problems.
Table 3-11. ESTIMATED EMISSION FROM WOOD WASTE BURNING
Pollutant
Sulfur dioxide
Oxides of nitrogen
Hydrocarbons
Organic acids
Aldehydes
Particulates
Emission factor,^
Ib pollutant per
1,000 Ib wood waste
0.08
0.06
10.0
0.2
0.9
1.3
Potlatch Forests
Incorporated,
Ib/day
10
77
1,285
26
115
167
Other saw
and planning
mills,lb/day
21
158
2,625
53
236
341
FUEL USAGE
NATURAL GAS
Of all the fuels used in the area, both for home heating and industrial
operations, natural gas is by far the "cleanest" from an air pollution
standpoint.
The users of natural gas are 8 industrial operations, 348 commercial
establishments, and 1,590 residences. *•$ The residential and commercial
40
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
users burn 146 million cubic feet, accounting for 3.6 percent of the
total gas usage. The industrial users, not including PFI, account for
88 million cubic feet, or 1.3 percent of the total. The remaining 95.1
percent is used by PFI and totals 6,270 million cubic feet a year. In
calculations of emissions, natural gas was assumed to have an approxi-
mate density of 0.048 pound per cubic foot and a sulfur content of 0.4
grain per hundred cubic feet.
Although natural gas combustion is clean compared with coal and
oil, the large volume burned partially compensates for the low emission
factors and results in atmospheric pollution (Table 3-12). The major
pollutants emitted by natural gas combustion are oxides of nitrogen,
aldehydes, and organic acids. For each of the above pollutants, natural
gas is a significant contributor to the total emission in the area. As
one would expect, because of the tremendous volume of natural gas
burned each day, PFI is the most significant source of emission from
the combustion of this fuel.
COAL, OIL, AND PRESTO LOGS
Coal and oil are predominantly used for home heating in the
Lewiston Orchards area. Both Lewiston and Clarkston have natural gas,
and the majority of homes and businesses use gas as a source of heat.
Presto log usage is not localized; most people in the area use them as
a secondary source of heat. Compared to natural gas, coal and oil are
relatively "dirty" sources of heat since they release more atmospheric
contaminants. Coal is worse than oil, with high emissions of oxides of
sulfur, hydrocarbons, and particulates. Oil has relatively high
emissions of sulfur oxides, nitrogen oxides, and particulates. The total
emissions depend on the amount and the chemical and physical proper-
ties of coal and oil used.
Coal, used primarily in the Lewiston Orchards area, has a sulfur
content of only 0.6 percent 21 by weight, which minimizes the amount
of sulfur oxides emitted to the air. Total coal usage is estimated at
7,000 tons per year. 22 The heating season in the area was assumed to
be 150 days long, and it was further assumed that the 7,000 tons of coal
were consumed during the heating season. Estimated emissions from
the use of coal are given in Table 3-13.
Sales of Number 1 and 2 fuel oils, used primarily for home heat-
ing, totaled 5.3 million gallons during the 5-month heating season. 23
Residual oil, which is used in large heating plants such as schools and
hospitals, was consumed at the rate of 1 million gallons during the
heating season. 23 The sulfur content of these oils was estimated as
0.5 percent by weight, and density of the oils was estimated as 7.29
pounds per gallon.
Presto log usage totaled 24,000 tons for the heating season 25 and
was assumed to be distributed over the whole area rather than concen-
trated in Lewiston Orchards. To estimate emissions from combustion
Sources of Air Pollution - Chapter HI 41
-------
Table 3-12. ESTIMATED EMISSIONS FROM COMBUSTION OF NATURAL GAS a
9
v
o
f
I-1
a
H
i—(
O
H
O
o
£
CO
H
i
Pollutant
Sulfur oxides d
Nitrogen oxides
Carbon monoxide
Aldehydes
Other organic
gases
Particulates
Gas consumer
Residential
and
commercial
(3.6 percent) b
Emission
factor,
lb/ 1,000 Ib
0.028
2.4
0.008
Neg
Neg
0.4
Emission
during
heating
season,
Ib/day c
2.3
80
<1
Neg
Neg
12
Industrial
All industry except
P.F.I.
(1.3 percent)b
Emission
factor,
lb/1,000 lb
0.028
4.5
0.008
0.05
0.1
0.37
Emission,
Ib/day
<1
50
Neg
0.5
1.0
4
Potlatch Forests
Incorporated
(95.1 percent)13
Emission,
Ib/day
24
3,680
7
34
86
300
Total
Emissions,
Ib/day
27
3,810
7
34
87
316
a Reference 20.
b Percent of total natural gas consumption.
c Assume 150 heating days per year.
d Assume sulfur content of natural gas as 0.4 grain/100 ft .
-------
to
o
Table 3-13. ESTIMATED EMISSIONS FROM COMBUSTION OF FUELS FOR RESIDENTIAL
AND COMMERCIAL HEATING a
Pollutant
Oxides of sulfur fe.. j
(as sulfur dioxide)
Oxides of nitrogen
(as nitrogen dioxide)
Hydrocarbons and
other organics
Aldehydes
(as formaldehyde)
Particulates
Fuel
Coalb
(7,000 tons per year)
Emission
factor, Ib
pollutant
per 1,000 Ib
fuel
11.0
0.2
5.0
f
12.0
Emissions
during
heating
season,
Ib/day
1,026
19
467
f
1,120
Oil
(6.3 million gallons
per year)
Emission
factor,c Ib
pollutant
per 1,000 Ib
fuel
9.9
9.0
0.5
0.25
1.5
Emissions
during
heating
season,
Ib/day
2,950
2,682
149
75
447
Presto logs
(24,000 tons per year)
Emission
factor,d Ib
pollutant
per 1,000 Ib
fuel
0.08
0.6
5.0
0.45
0.65
Emissions
during
heating
season,
Ib/day
24
180
1,500
135
195
Total
emissions
during
heating
si~. on,
IbA y
4,000
2,881
2,116
210
1,762
a?
o
I
O
I
to
l-t
a Emissions calculated on basis of 150-day heating season.
b Assumed to be residential use - heating and cooking.
c Reference 24.
d Reference 17.
e Sulfur contents: coal, 0.6%; oil, 0.5%; presto logs, 0.004%.
Included with hydrocarbon.
-------
of this fuel, the sulfur content was assumed to be that of pine wood, and
emission factors determined for burning waste wood were applied.
The major contaminants released to the air from the combustion of
oil, coal, and presto logs are seasonal, localized, and consist mainly of
sulfur and nitrogen oxides, hydrocarbons, and particulate material
(Table 3-13.)
FUEL USED IN MOTOR VEHICLES
Consumption of gasoline and diesel fuel in the area is estimated as
8 million gallons a year for gasoline 23 and 20 thousand for diesel
fuel. 26 The major pollutants from gasoline usage are hydrocarbons,
oxides of nitrogen, and carbon monoxide. Compared with the emissions
from gasoline engines, diesel engine emissions are lower in total hydro-
carbons and oxides of nitrogen, and higher in particulates.
Table 3-14 presents the emission factors used to calculate the
emissions of various pollutants and the results of the calculations.
Emissions from vehicle exhaust would be most concentrated in the down-
town area during peak traffic hours. Hydrocarbons and oxides of nitro-
gen are important emissions since they enter in the so-called photo-
chemical smog reaction. Urban area carbon monoxide is also signifi-
cant since this toxic gas can reach rather high levels during heavy
traffic hours.
REFUSE DISPOSAL
There are two major refuse disposal sites in the area, one in
Lewiston Orchards and one north of Clarkston near the river. Back-
yard burning is permitted in both Lewiston and Clarkston and in unin-
corporated Lewiston Orchards and Clarkston Heights.
In Lewiston refuse is collected daily from restaurants and busi-
nesses and weekly from residences by a private contractor. All house-
holds and businesses are required to subscribe to the refuse collection
service. Backyard burning is permitted in Lewiston, and approximately
20 percent of all refuse is disposed of in this manner. 27 The bulk of
the refuse, 80 percent, is hauled to a sanitary landfill operation, and
little if any burning takes place.
Lewiston Orchards has voluntary refuse collection, and residents
who do not avail themselves may haul their own refuse or burn it in the
backyard. It is estimated that 50 percent of the refuse in Lewiston
Orchards is burned by residents and the remainder hauled to the land-
fill.
Clarkston provides a mandatory refuse collection service, but
subscription to this service is not adequately enforced. 28 Refuse is
collected three times weekly from restaurants and businesses and
44 AIR POLLUTION IN LEWIS TON-CLARKSTON AREA
-------
Table 3-14. EMISSIONS FROM MOTOR VEHICLES
Pollutant
Total hydrocarbons
Oxides of nitrogen
Carbon monoxide
Sulfur dioxide
Aldehydes
Organic acids
Ammonia
Particulates
Gasoline
factor,a
Ib/gal
0.300
0.100
3.0
0.007
0.005
0.002
0.002
0.0003
Diesel
factor,b
Ib/gal
0.715
0.222
-
0.015
0.016
0.031
-
0.086
Emissions
from
gasoline,
Ib/day
6,580
2,195
65,800
154
110
44
44
6.5
Emissions
from
diesel fuel,
Ib/day
39
12
-
1
1
2
-
5
Total,
Ib/day
6,619
2,207
65,800
155
111
46
44
12
a Reference 20_
b Reference 17
once weekly from residences. It is estimated that 20 percent of the
refuse in Clarkston is burned in backyard incinerators by residents and
that the remaining 80 percent is collected by the City. In Clarkston
rubbish burns more or less continually -with the consequent emission of
odors, smoke, and particulate matter. Approximately 1,000 householders
immediately adjacent to the City of Clarkston have a voluntary collection
program that has 150 subscribers. The remainder of the householders
burn their refuse in incinerators.
Clarkston Heights has no refuse collection, and approximately 80
percent of all refuse is burned by residents and the remainder hauled to
the Clarkston dump.
The per capita production of rubbish is estimated as 1,400 pounds
per person per year; 29 the combustible content of all refuse is assumed
to be 70 percent. Population estimates were based on the 1960 census
figures. 30
Table 3-15 presents the calculated emissions from each source as
well as the emission factors used. This table does not include an estima-
tion of the odor problem from waste burning. Odors can, however, be a
considerable problem when large amounts of garbage are burned, and an
attempt has been made to evaluate the problem in the odor survey section
of this report. The most important emissions from refuse burning are
Sources of Air Pollution - Chapter III
45
-------
carbon monoxide and particulates. Combustion of refuse does not con-
stitute a major source of pollution, but at times may be the cause of
local irritation and complaint.
Table 3-15. ESTIMATED EMISSIONS FROM COMBUSTION OF REFUSE
Pollutant
Oxides of sulfur
(as sulfur dioxide)
Oxides of nitrogen
(as nitrogen dioxide)
Total hydrocarbons
Aldehydes
(as formaldehyde)
Other organic gases
Carbon monoxide
Particulates
Emission
factor,a
Ib per Ib
burned
0.0015
0.002
0.003
0.005
0.004
0.02
0.011
Emissions, Ib/day
Lewiston
Backyard
burning
10
14
20
34
28
140
76
Lewiston .
Orchards
Backyard
burning
20
26
39
65
52
260
143
Clarkston,
Clarkston Heights,
and adjacent area
Backyard
burning
17
22
33
55
44
220
121
Dump
burning
21
28
43
71
57
284
156
Total
68
90
135
225
181
904
496
^Reference 20.
SUMMARY
An estimate of major air contaminant emissions for the area was
made from information provided by the communities and industries in
the area. No stack sampling was done. All estimates were based on
information from the literature and other sources.
The major contributor of hydrogen sulfide and other malodorous
organic gases is the kraft pulp mill. In addition, the pulp mill contri-
butes about 77 percent of the estimated gaseous emissions and about 82
percent of the estimated particulate emissions. It also contributes an
estimated 4,640 tons of water vapor each day to the atmosphere. This
is thought to have a significant effect on the humidity in the valley under
certain meteorological conditions. The major gaseous emission from
the pulp mill is the "combustible" from three recovery furnaces and
three lime kilns. This combustible probably consists of carbon mon-
oxide and partially oxidized organic compounds.
46
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
The pulp mill has installed many control devices, but the recovery
furnaces and kilns may, from time to time, permit a substantial emission
of odorous compounds to the atmosphere. A sulfate pulp mill also has
innumerable small sources of odor emissions that in total may constitute
a difficult problem.
Emissions from other industrial operations are relatively small.
Home heating is the largest source of sulfur oxides, while transportation
(gasoline engine exhaust) contributes a substantial amount of carbon
monoxide to the atmosphere. Refuse disposal is a relatively minor
source of air contamination on a weight basis, but the odor produced by
burning garbage and refuse can cause local nuisances.
REFERENCES
1. Wright, R.H. The Reduction of Odors from Kraft Pulp Mills.
Technical Bulletin 27. British Columbia Research Council. 1961.
2. Hansen, G.A. Odor and fallout control in a kraft pulp mill. J. Air
Poll. Control Assoc., 12:409. 1962.
3. Collins, T.T., Jr. The oxidation of sulphate black liquor, Paper
Trade J. 130:30-38. October 12, 1950.
4. National Council for Steam Improvement. Atmospheric Pollution.
Technical Bulletin No. 16. 1962.
5. Wright, R.H. New work in kraft mill odor control. J. Air Poll.
Control Assoc., 13:101. 1963.
6. Private communications, C.J. Hopkins, Potlatch Forests Incorporated,
Lewiston, Idaho.
7. Private communication, Sven O. Hultin, Deputy Managing Director,
Ekono, Helsinki, Finland.
8. Private communication from Sven O. Hultin, Deputy Managing Dir-
ector, Ekono, Helsinki, Finland to Potlatch Forests Incorporated,
Lewiston, Idaho.
9. DeHass, G.G. and Hansen, G.A. The abatement of kraft pulp mill
odors by burning. TAPPI, 38:732-738. Dec. 1955.
10. First, M. W., Friedrich, H.E., and Warren, R.P. TAPPI, 43:182A.
June 1960.
11. Calkin, John B., Modern Pulp and Paper Making, 3rd edition.
Reinhold, New York. 1957.
12. Bergstrom, H. and Trobeck, K.G. Sulfur losses in the production of
sulfate pulp. Svensk Papperstidin, 48:49-54. 1945.
13. Trobeck, K.G., Lenz, W., and Tirado, A. Elimination of malodors
in a kraft pulp mill. TAPPI, 42:425-432. June 1949.
Sources of Air Pollution - Chapter HI 47
-------
14. Bernhardt, A.A. and Buchanan, J.S. Recovery of dissolver vent
stack soda losses. TAPPI, 43:191A-193A. June 1960.
15. Johnson, A.J. and Auth, G.H. Fuels and Combustion Handbook.
McGraw-Hill Book Co., New York. 1951. p. 114.
16. Murphy, G. Properties of Engineering Materials, 3rd edition.
International Textbook Co., Scranton, 1957. p. 311.
17. The Louisville Air Pollution Study, SEC Tech. Report, A61-4.
Public Health Service, Cincinnati. 1961.
18. Kenline, P. Control of air pollution from chemical processing
plants. Unpublished Literature Review. Public Health Service,
Cincinnati.
19. Private communication, Washington Water and Power Company.
20. Weisburd, M.I. Air Pollution Control Field Operations Manual.
Public Health Service Publication No. 937. Cincinnati. 1962.
21. Johnson, A.J. and Auth, G.H. Fuels and Combustion Handbook.
McGraw-Hill Book Co., New York, 1951. Table 4-1, p. 86.
22. Private communication, Harold Uglemb, Home Lumber Company.
23. Private communication, Shell Oil Company.
24. Smith, W. Atmospheric Emissions From Fuel Oil Combustion,
Publication No. 999-AP-2, USDHEW, Public Health Service,
Robert A. Taft Sanitary Engineering Center, Cincinnati. 1963.
25. Private communication, Potlatch Forests, Incorporated.
26. Private communication, G. Freeman, North Central District
Health Department, Lewiston, Idaho.
27. Private communication, G. Freeman, North Central District
Health Department, Lewiston, Idaho.
28. Private communication, S. Dean Arnold, City Attorney, City of
Clarkston, Washington.
29. Municipal Refuse Disposal. Chapter 2. Public Administration
Service. Chicago, Illinois. 1961.
30. Hansen, H. The World Almanac, New York World Telegram and
the Sun. New York. 1961.
48 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
CHAPTER IV. EVALUATION OF AIR QUALITY
DESCRIPTION OF SAMPLING STATION
GENERAL CONSIDERATIONS
In this study seven sampling stations were established (Table 4-1
and Figures 4-1 through 4-6). Six were set up with AISI hydrogen sulfide
tape samplers and silver and paint panels. The seventh was a meteoro-
logical station on the post office building in Lewiston. Here wind speed,
wind direction, temperature, and relative humidity were measured. In
addition to this basic equipment, one station in Clarkston (the City Hall
fire station site) had a high-volume air sampler and gas analysis equip-
ment for hydrogen sulfide and sulfur dioxide. Two others had high-
volume samplers - the courthouse station in Lewiston and the control
station at the Waterworks in Moscow, Idaho. The post office in Lewiston
has been used as a reference point for evaluation under the assumption
it represented the valley floor.
CLARKSTON
HIGHLAND J AVE
Figure 4-1. Station location map.
Evaluation of Air Quality - Chapter IV
49
-------
CJ1
o
Table 4-1. DATA ON SAMPLING STATIONS
Name and location
of sampling stations
1. Moscow, Idaho. In
water pumping
station.
2. Lewiston Or-
chards. In Warmer
Grade School
building.
3. Lewiston Residen-
tial, In old Lewis-
ton Junior High
School.
4. Lewiston Com-
mercial. In Lewis-
ton Courthouse.
Height
above
valley,
ft
1,965
659
135
0
Height
above sea
level, ft
2,700
1,394
870
735
Type of area
Residential and
commercial.
Residential, with
small gardens and
fields.
Residential, at
intermediate eleva-
tion between Lewis-
ton Orchards and
Lewiston Commer-
cial.
Commercial and
light industrial.
Observational
quality
No obstructions, except
for several 2- story
buildings some distance
away.
Bordered on west and
south by playgrounds,
and on north and east
by roads ana residence.!
No obstructions. Large
playfield south of
building.
Minor obstacles. Some
3-story buildings to
north and south.
Potential pollution
sources nearby
Space heating and auto
exhausts. No major
source.
Residential heating,
auto exhausts, blow-
ing dust. No major
source.
No major source.
Residential heating,
auto exhaust. Traffic
east of station only.
Smokestack of court-
house, feed mill to NW,
auto exhaust, other
heating smokestacks.
Type of
equipment
H2S tape sampler on 1st
floor, 8 paint samples
on tower on roof, silver
samples atop tape
sampler. High-volume
particulate sampler on
roof for three 2-week
periods.
H2S tape sampler indoors,
8 paint samples on ex-
terior of building, silver
samples inside.
H2S sampler (AISI) on 2nd
floor, NE corner, 8 paint
samples attached to out-
side walls. Silver samples
indoors.
H2S tape sampler on 3rd
floor on north side, 8
paint samples on outside
walls. Silver samples
atop tape sampler. High-
volume particulate
sampler on roof, for
three 2-week periods.
Remarks
Used as the control
station because of
nonindustrial area.
Roof 25 ft above
ground. Teflon probe
extended to outside
air.
Teflon probe extended
to outside air, 12 ft
above ground.
Streets north and west
of building blocked
off. Teflon probe ex-
tended to outside air,
35 ft above ground.
Teflon probe extended
to outside air, 35 ft
above ground. Roof
45 ft above ground.
5
GO
H
o
g
11
I 5
N 70
? 63
-------
Table 4-1. DATA ON SAMPLING STATIONS (Continued)
Name and location
of sampling stations
5. West Clarkston. In
Highway Department
utility shed.
6. Clarkston Com-
mercial. In Clark-
ston City Hall.
7. Lewiston Meteoro-
logical Station. In
Lewiston Post
Office building.
Height
above
valley,
ft
13
84
0
Height
above sea
level, ft
748
819
7355
Type of area
Residential and
rural.
Commercial and
residential.
Commercial and
residential. Some
light industry.
Observational
quality
Only obstructions were
a large storage build-
ing to the west and
several tall houses to
east. Open pasture
north and south.
No tall obstacles. Park-
ing and vacant lots ex-
tend 100 to 300 ft in
three directions.
Little obstruction. Two-
story building to south,
and other 2-story build-
ings to NW and SE,
several hundred feet
away.
Potential pollution
sources nearby
Residential space heat-
ing, auto exhausts.
Commercial smoke-
stacks, auto exhausts,
windborne ground
dust.
Commercial and resi-
dential smokestacks,
auto exhausts, some
light industry to the
north.
Type of
equipment
H2S tape sampler inside
shed, 8 paint samples on
outside walls, silver
samples near the tape
sample.
Three H2S tape samplers,
inside the fire station.
Two sequential samplers,
for H2S and SO 2 for three
2-week periods. Eight
paint samples on outside
walls. High-volume par-
ticulate sampler on roof.
Instruments for recording
wind speed, wind direc-
tions, relative humidity
and temperature.
Remarks
Teflon probe extended
to outside air 10 ft
above ground.
Inlet line to one sampl-
er submerged in con-
stant temperature
water bath. Teflon
probe extended to out-
side air, 10 ft above
ground.
Instruments located
on roof. Wind speed,
wind direction, rel-
tive humidity, tem-
perature recorded
continuously here
Jan. - Apr. 1962.
Wind instrument on
mast 18 ft above
roof and 46-1/2 ft
above ground. Tem-
perature and rela-
tive humidity re-
corder 33-1/2 ft
above ground.
Station simulates
the old Weather
Bureau Station that
was here until 1948.
o
£>
o
50
-------
Figure 4-2. Lewiston Orchards sampling station. View
of Warner Grade School shows sample inlet tube.
ATMOSPHERIC PARTICULATE MATTER
GENERAL
Twenty-four-hour atmospheric particulate samples were collected
for 14 consecutive days during each of the study periods in November
1961, January 1962, and April 1962, at three permanent sampling sites
in Lewiston, Idaho; Clarkston, Washington; and Moscow, Idaho. Partic-
ulates were separated by filtration through 8- by 10-inch glass fiber
filters held in high-volume air samplers and were collected at flow rates
of 40 to 60 cubic feet of air per minute. The variation in flow rate
depended upon the nature and amount of participates deposited. Sample
filters were changed daily between 1500 and 1700 hours, and the mea-
surements were dated and recorded as of the day sampling ended. The
samples were analyzed for total particulates, and for sulfate, sodium,
and calcium content.
RESULTS
Atmospheric particulate loadings, reported in micrograms of dust
per cubic meter of air, at both the valley sites (Lewiston and Clarkston)
52
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
Figure 4-3. Lewiston residential sampling station.
Exterior and interior views of old Junior High School show
AISI sampler and silver sample in upstairs window.
Evaluation of Air Quality - Chapter IV
53
-------
Figure 4-4. Lewiston commercial sampling station No. 4.
Hi-vol sampler on roof of Lewiston Courthouse.
and the mountain plateau, nonindustrialized control site (Moscow) were
lowest during January (Table 4-2). Highest average particulate loadings
occurred in Moscow and Clarkston during April. During November and
January particulate loadings were generally higher in Lewiston than in
Clarkston and lowest in Moscow. It can be observed from Figure 4-7
that particulate loading often varied directly with wind speed and
inversely with degree-days.
Meteorological data for the valley sites were obtained at a weather
station in Lewiston, established for this study, and at the Nez-Perce
Airport weather station. Weather data for Moscow, obtained at the
Pullman-Moscow Airport, were available only during the April study
period. Estimated meteorological data for November and January are
used for the purpose of comparison. From topographical features and
previous records, it is reasonable to assume that during the study
periods wind speeds were generally higher and temperature generally
lower in Moscow than in the valley. The positive relationship between
wind speed and particulate loading indicates that the total air-borne
particulate content is greatly influenced by wind entrainment of solid
material from the ground. Frozen ground conditions and snow cover
minimized atmospheric particulate concentrations during January.
54
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
§
Table 4-2. ATMOSPHERIC PARTICULATE CONCENTRATIONS AND
METEOROLOGICAL PARAMETERS
Date
November
6-19
January
9-22
April
16-29
Lewiston
particulate
concentration,
/Ag/m3 a
Max.
282
160
328
Min.
96
46
40
Avg
183
118
147
Clarkston
particulate
concentration,
/ig/m3 a
Max.
272
120
459
Min.
57
63
38
Avg
155
85
164
Average
wind
speed, b
mph
5
4
6
Total
degree-
days c
401
586
137
Moscow
particulate
concentration,
/ig/mS a
Max.
287
165
1,047
Min.
61
30
80
Avg
132
66
235
Average
wind
speed, c
mph
d
d
9
Total
degree-
days c
d
d
191
9
•ft
to
a Concentration is expressed as micrograms of dust per cubic meter of air.
b Measurement obtained from weather station at Nez-Perce Airport in November and from special
weather station in Lewiston during January and April.
c Measurements obtained from weather station at Pullman-Moscow Airport.
d Data are not available.
-------
Figure 4-5A. Clarkston commercial sampling station No. 6, Clarkston City Hal
and Fire Station. Samplers inside Fire Station included
conTrolled-tempeiature, standard, and Idaho State Health
Department AISI tape samplers.
56
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
:>•••%• '
• ,
Figure 4-5B. Clarkston commercial sampling station No. 6. Samplers inside Fire
Station included Gelman sequential gas sampling apparatus.
Hi-vol sampler was on top of Fire Station.
Evaluation of Air Quality - Chapter IV
57
-------
Figure 4-6. Post Office meteorological station. View of roof shows aerovane.
58
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
600 -
200-
300
o> 200
100
50
ll
1
SAMPLING
LOCATION
•LEWISTON
OCLARKSTON
D MOSCOW
OBSERVED
HMOSCOW
ESTIMATED
NOV.6-19 JAN.9-22 APR.16-29
SAMPLING PERIODS
Figure 4-7. Comparison of atmospheric participate
loading with wind speed and degree-days.
Microscopic examination of several samples revealed large quan-
tities of inorganic dusts, such as quartz and gypsum, particularly in
samples collected during April and to a lesser extent in November.
Particles derived from the incomplete combustion of wood and
other combustible material were also observed. The number of these
particles was greater during January than November, which agrees
with the amount of fuel used for heating. The number was lowest in
April. Total atmospheric particulate loading varied inversely with
degree-days, however, indicating that emissions of participates in the
atmosphere from the combustion of fuels for heating make only a minor
contribution to over-all pollution, which leads in turn to the conclusion
that the atmospheric participates originate largely from natural and
industrial sources.
The percentage compositions of sulfates and sodium in the partic-
ulate samples were significantly higher in Lewiston and Clarkston than
in Moscow (Table 4-3). Calcium compositions did not vary significantly,
Evaluation of Air Quality - Chapter IV
59
-------
indicating natural sources such as wind entrainment of ground dusts for
the presence of calcium in samples. Sodium oxide and sulfate are dis-
charged in large quantities in the black liquor recovery furnace process
of a sulfate process pulp mill without recovery equipment or with poor
recovery equipment. Large quantities of sulfate are also discharged in
solid and liquid fuel-burning operations, but emissions from fuel used
for heating did not contribute to a major extent to the total air pollution.
CONCLUSIONS REGARDING PARTICULATES
The relationship of particulate air pollution and meteorological
data indicates that, during November 1961 and January and April 1962,
the major sources of atmospheric particulates were industrial emissions
and natural ground dusts entrained by wind. Analysis of the composition
of particulates indicates that industrial processes resulting in discharge
of sodium and sulfate compounds contribute substantially to the total
atmospheric particulate pollution in Lewiston and in Clarkston.
Table 4-3. AVERAGE COMPOSITION OF ATMOSPHERIC
PARTICULATES SAMPLED a
Location
Lewiston
Clarkston
Moscow
Percent
Sulfates
21.7
21.4
14.5
Sodium
3.5
3.0
1.3
Calcium
2.0
3.0
2.9
a Based on analysis of 40 samples and 40 determinations
of each constituent.
VISIBILITY
Reduction of visibility is one of the most obvious and easily
detected manifestations of atmospheric pollution. Reduction of visi-
bility is caused by two physical mechanisms, both related to the
presence of pollutant aerosols in the air: light scattering and light
absorption. Light is scattered when it is refracted by aerosols in the
atmosphere. Greatest scattering occurs when the wave length of the
incident light is approximately equal to the diameter of the aerosols.
Absorption of light is generally caused by the larger sized aerosols and
does not affect visibility as greatly as scattering.
The most common visibility-reducing agents are particulate matter
and water vapor in the form of fog. Many types of particulates occur
naturally, but by far the most are man-made fly-ash, industrial dust,
60
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
etc. Studies have shown that fog can be induced by the presence of
particulates. Particulates provide convenient condensation nuclei for
water vapor in the atmosphere.
Although reduction in visibility can indicate the presence of atmos-
pheric pollution, it is by no means the most reliable index. Many pol-
lutants, such as gases, do not reduce visibility, and not all reductions
in visibility are caused by atmospheric pollutants.
METHODOLOGY
Visibility Observations
Observations of visibility were made from the roof of the Lewiston
Post Office Building each morning and afternoon from November 8, 1961,
to April 30, 1962. Prominent objects in each direction were chosen as
markers and their distances determined. A map was prepared with
concentric circles around the Post Office showing the direction and
distance of each marker (Figure 4-8). Each observation included the
distance of the farthest marker visible in each direction.
The topography of the Lewiston area does not lend itself well to
this method of visibility observations. Because the observation point
is in a valley surrounded by high ground, the distance to the farthest
marker in each direction varied from 1/4 to 1 mile. These distances
are too short for an optimum visibility observation program.
Airport Smoke Observations
Observations of smoke in the valley made by the Weather Bureau
station personnel at the Lewiston Airport from July 1943 through
October 1959 have also been used to analyze the incidence of visibility-
reducing pollution.
Photographs
Photographs were taken in a northerly direction from an elevation
of 1,250 feet approximately 1-1/2 miles south of Lewiston, from
November 16, 1961, to February 21, 1962, to provide a visual record
of the incidence and severity of pollution in the valley.
Airport and City Meteorological Data
Data from the previously described meteorological stations at the
Lewiston Airport and the Lewiston Post Office were used in the analysis
of the airport smoke reports to relate the incidence of smoke in the
valley with pertinent weather data such as relative humidity, wind
direction, etc.
Evaluation of Air Quality - Chapter IV 61
-------
2 mite
Figure 4-8. Visibility map of Lewiston-Clarkston area.
VISIBILITY IN THE VALLEY
Past History
A review of the smoke reports by the Lewiston Airport Weather
Bureau Station shows that the incidence of smoke in the valley in 1959
was about 3-1/2 times what it was in 1948 (Figure 4-9). Where smoke
was reported an average of 5 days each month in 1948, the average
was 18 in 1959. In February 1959, smoke was reported 26 days.
Figure 4-10 shows the average monthly variation of smoky days
for the period from 1948-1959. As can be expected, the incidence of
smoky days was greatest during the winter months when inversion
conditions were most persistent.
62
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
~
VEAR
Figure 4-9. Annual airport observation of smoke over
the city, 1948-1959.
IS
00
i i i r
J L
j L
JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT. OCT. NOV DEC.
MONTH
Figure 4-10. Seasonal variation of airport observations
of smoke over the city, 1948-1959.
Evaluation of Air Quality - Chapter IV
63
-------
An attempt was made to evaluate the effect on visibility caused by
locating the pulp mill there in 1951. Data from the Lewiston Airport
smoke reports (Figure 4-11) show that before 1951, i.e., 1948 through
1950, smoke was reported an average of 5.6 days a month. Since 1951
(1952 to 1959 inclusive) smoke has been reported on average of 12.5
days a month, an increase of about 2-1/4 times.
The Study Period
Because of the extremely short distances to the landmarks, the
data collected from visibility observations at the Lewiston Post Office
are not conclusive. Normally, distances of 20 to 25 miles are necessary
for satisfactory visibility evaluations by visual methods. Since the
maximum range possible in the study was 1 mile, a completely valid
study of visibility was not attainable. One significant fact did, however,
emerge: on 17 of the 119 days during which observations were made,
the amount of pollution was great enough to reduce visibility to less than
1 mile. Figure 4-12 illustrates the typical view in each direction on a
clear day and on a day with reduced visibility. Notice that although
visibility is markedly reduced to the north, east, and west, observation
to the south shows little reduction. From January 1, 1962, to April
30, 1962, the Airport Weather Station reported smoke over the valley
71 of 120 days. Most of these reports were in the morning hours, from
0400 to 1200 hours as shown in Table 4-4.
The high incidence of plumes reported in the morning hours is
reasonable because this is normally a time of high relative humidity.
As shown in Table 4-5, the humidity was generally higher when smoke
JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT. OCT. NOV DEC
MONTH
Figure 4-11. Comparison of seasonal variation of airport
observations of smoke over the city,
1948-1950 versus 1952-1959.
64
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
NORTH
EAST
SOUTH
WEST
Figure 4-12. Visibility observations from Lewiston Post Office building.
Evaluation of Air Quality - Chapter IV
65
-------
was reported. A comparison of average relative humidities before
and after the establishment of the pulp and paper mill (Table 4-6) shows
that at the city station the humidity was significantly higher during the
study period than during the period of 1924 to 1933.
Table 4-4. MORNING AND AFTERNOON AIRPORT
OBSERVATIONS OF SMOKE OVER THE CITY,
NOVEMBER 1961 THROUGH APRIL 1962
Month
November
December
January
February
March
April
Frequency of smoke over city, %
0400-1200 hours
62
68
63
57
81
89
1300-2000 hours
38
32
37
43
18
11
Table 4-5. RELATIONSHIP OF 0800 RELATIVE HUMIDITY
AND AIRPORT OBSERVATION OF SMOKE OVER THE
CITY, JANUARY 1962 THROUGH APRIL 1962
Month
January
February
March
April
Observation
Smoke over city
No smoke over city
Average for month
Smoke over city
No smoke over city
Average for month
Smoke over city
No smoke over city
Average for month
Smoke over city
No smoke over city
Average for month
Average relative humidity, %
Airport
75
62
66
88
73
77
80
80
80
72
60
64
City
84
69
74
92
85
87
94
91
92
81
69
74
66
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
GPO B \ 6—92O—6
-------
Table 4-6. COMPARISON OF CITY AND AIRPORT
RELATIVE HUMIDITIES FOR STUDY
PERIOD AND FOR 1924 TO 1933
Month
November
December
January
February
March
April
Relative humidity, %
City
Study period
-
-
74
92
99
94
1924-1933
83
79
79
79
77
74
Airport
Study period
76
79
70
77
82
71
The moisture emitted from the pulp and paper mill has had a signifi-
cant effect on the relative humidity in the valley, and it is evident that
the increased humidity and particulates have adversely affected visi-
bility in the valley.
A study of the relationship between wind direction and incidence
of smoke in the valley is also revealing. During the hours when smoke
was reported in the valley, the wind was most frequently out of the
easterly quadrant, i.e., northeast to southeast. Figure 4-13 shows the
frequencies for the 6 months of the study period. As can be seen, more
than 40 percent of the smoke observations occurred when winds were
from the east.
Photographs of the effects of the pulp mill on visibility in the valley
are even more revealing. Figure 4-14 was made on December 25, 1961,
at 0945. It views the valley from the south and illustrates the situation
when the pulp mill was not in operation. Figure 4-15 was made on
November 30, 1961, at 0900 and shows that an inversion over the valley
prevents the dispersion of the effluent from the pulp mill. Figures
4-16 through 4-19 show the effect of the pulp mill under various condi-
tions of stability and wind direction. Figure 4-16 is particularly in-
teresting since it illustrates the usual wind current in the valley. Even
though the wind is from the east at the mill, almost every portion of the
valley beneath the inversion is affected. Figure 4-20 shows examples
of uncontrolled sources of smoke in Clarkston.
Evaluation of Air Quality - Chapter IV
67
-------
NOVEMBER
DECEMBER
JANUARY
FEBRUARY
MARCH APRIL
NOTE-VALUES ARE IN PERCENT. CALMS ARE RECORDED IN CENTER CIRCLE
Figure 4-13* Frequency of wind direction when smoke
reported over the city, November 1961
through April 1962.
68
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
I
•§
(B
>•<
Figure 4-)4. Lewiston-Clarkston valley, Dec. 25, 1961, at 0945.
05
<£>
Figure 4-15. Lewiston-Clarkston valley, Nov. 30, 1961, at 0900.
-------
-J
o
r
c
O
Z
Figure 4-16. Ponoramo of volley looking south from north of Lewiston, Feb. 3, 1962, at 0900.
H
O
Z
O
w
H
O
33
n
Figure 4-17 Lewiston during calm,
Feb. 3, 1%2. at 0900.
Figure 4-18. Pulp mill effluent during
west w.nd, Dec. 3, 1961, at 0830.
-------
Figure 4-19. Pulp mill effluent during unstable conditions
and calm wind, Jan. 16, 1962, at 0830.
CONCLUSIONS REGARDING VISIBILITY
A rather severe visibility reduction problem exists in the Lewiston-
Clarkston valley. Basically, the data from this study as well as meteor-
ological data for periods of time prior to the study were correlated
with the incidence of smoke in the valley. The greatest occurrence of
smoke resulted from a stable, ambient atmosphere with high relative
humidity and an easterly wind. The topography itself helps create a
stable atmosphere with frequent inversions. As a result of economic
activity in the valley, relative humidity seems to have increased to the
point that particulates induce fogs more easily. Fogs combined with
the smoke emissions from all sources have caused many incidents of
significantly reduced visibility in the valley.
HYDROGEN SULFIDE
NATURE OF THE GAS
Hydrogen sulfide (^S) is a colorless gas that has, even in very
small concentrations, an offensive odor described as that of rotten eggs.
It occurs naturally when sulfur-containing organic matter decomposes
without complete oxidation. It results also from man-made processes
Evaluation of Air Quality - Chapter IV
71
-------
72
Figure 4-20. Major sources of air pollution in Clarkston,
a garbage dump, a brush dump, and a saw mill waste burner.
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
such as the manufacture of petroleum products, paper, and many chem-
ical compounds. As shown by the emission inventory (Chapter 3), the
primary source of I^S and other odorous gases in the Lewis-Clarkston
area is the kraft pulp mill.
The minimum concentration of I^S that is detectable is debatable.
A review of the literature reveals nearly a thousandfold variation in the
reported odor threshold values for this gas. Wright, a recognized
authority on kraft pulp mill odors, states that one part of I^S per billion
parts of air is the minimum perceptible concentration. •"• Smith, Jen-
kings, and Cunningworth have suggested that 20 parts per billion (ppb)
is detectable as an offensive odor, 2 whereas Moncrieff 3 suggested 100
ppb. Other scientists found that 7 to 36 parts of I^S per billion parts of
air gave slight odors in households, where constant concentrations are
hard to obtain; in controlled laboratory tests, however, the lower limit
was 72 ppb. ^ Dalla Valle proposed 790 ppb as the concentration causing
faint odor. •* Others have proposed 25 and 130 ppb. ®>f
These authors have used the words "perception of faint odor." At
the "perception threshold" concentrations, one is just certain that an
odor exists, but it is too faint for identification. The "recognizable
threshold" is the smallest concentration at which a skilled observer can
identify and describe the odor or at least compare its quality with another
odor.
Although the range of reported values may at first appear to be
wide, one must remember that, according to the Weber-Fechner Law,
the perception by smell of a change in apparent odor intensity requires
a change in actual concentration by a factor of approximately 10, vary-
ing somewhat with the odor type. Thus, the sensation increases as the
logarithm of the concentration of the stimulus. As reported by Stern, ^
the empirical dilution factor for IfcjS is 5.9 and that for methyl mercap-
tan is 14.
Hence, the minimum detectable odor for H2S probably ranges from
about 10 or 15 to near 100 ppb. An ultrasensitive person might detect
1 ppb whereas a nonsensitive person may be unable to detect concen-
trations less than 500 ppb.
H2S tarnishes silver and copper rapidly in concentrations of 500
ppb and slowly in concentrations as small as 3 ppb. ® Paint blackening
occurs when lead base paint, moistened with water, is exposed to the
gas.
Regarding standards for protecting human health, only two have
been established. The Russians have established a limiting value of
5.15 parts of I^S per billion at one time (20-minute period) or in a 24-
hour period as their standard for community air quality. 1 The State of
California has established a concentration of 100 ppb for Ihour as the
"adverse level" based on sensory irritation. 9
Evaluation of Air Quality - Chapter IV 73
-------
H2S is not commonly used as a measure of air quality. Since con-
centrations arising from natural sources are generally small, H^S is
not usually measured, unless it is suspected that concentrations are
large enough to constitute a problem. Since a major source of I^S gas
existed in the study area, it was necessary to measure it.
All air samples for H2S collected in this study were 2-hour samples.
When H2S is sampled over a specific time period, for example 2 hours,
the concentration measured is actually an average of many instantaneous
or short-term values, large and small. If the sampling time is short,
the concentration measured should be very close to the peak instantan-
eous value that occurred. The resulting peak-to-mean ratio would be a
small number not much greater than unity. As the sampling time is in-
creased, the probability that the average value recorded will be close
to the highest instantaneous mean is reduced and the peak-to-mean ratio
is larger. Attempts have been made to estimate the short-term peak
concentrations from measurements based on a long sampling period.10'
IM2 One author reports the greatest 3-minute concentration of gas to
be 3.4 times the mean concentration over 1 hour for stable atmospheric
conditions and 8 times the mean for an unstable atmosphere. ^ This
means that the greatest 3-minute concentration of a gas probably was
3.4 to 8 times larger than that actually recorded for a 2-hour sampling
period, depending on the stability of the atmosphere. The same reason-
ing has been applied to estimating 1-hour peak values from 2-hour
samples. These ratios range from 1.3 for stable to 1.5 for unstable
conditions.
AREA CONCENTRATIONS
H2S samples were collected at six stations with treated-filter tape
samplers. 13 l^S varied significantly among the stations in the valley
and those in Lewiston Orchards and Moscow. A frequency distribution
of H^S concentrations by area for the 6-month study period shows that
the Lewiston commercial station and both stations in Clarkston had the
highest frequency of H^S pollution. Lewiston commercial was highest;
it was closest to the major source of H2S (Table 4-7). It is expected
that whenever there are measurable concentrations of I^S at any of the
stations, the elevated plume from the primary source is moving or has
just previously been moving toward the west along the major axis of the
valley. The frequency of large concentrations decreases with greater
distance of the stations from the river (farther from the centerline of
the plume). For stations at about the same distance from the river, the
average frequency of large concentrations is less at the stations farther
from the major source (West Clarkston compared to Lewiston com-
mercial).
Although the Lewiston commercial station had the highest average
frequency of large concentrations, both the West Clarkston and Clarkston
commercial stations had high frequencies of concentrations 3 ppb or
greater. As is shown later, this was due to inversion breakup and
fumigation at an earlier time in Clarkston. By the time fumigation
occurs in Lewiston (1200 to 1400 hours), wind speeds have generally
74 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
increased, diluting the plume, and reversal of windflow to upvalley flow
frequently keeps concentrations small (less than 3 ppb) at Lewiston at
this time. Peak values of 10 ppb or greater were recorded most fre-
quently at the Lewiston commercial station and the two stations in
Clarkston, each being close to the centerline of the plume from the
major source of hydrogen sulfide.
Percentages for the Moscow control station indicate the relatively
low H2S values recorded in the nonindustrial community.
Table 4-7. FREQUENCY DISTRIBUTION OF HYDROGEN
SULFIDE CONCENTRATIONS, BY AREA,
FOR STUDY PERIOD
Hydrogen
sulfide
concen-
tration,
ppb
0-2
3-9
^10
F3-equency at sampling station, %
Moscow
96.0
4.0
0
Lewiston
Orchards
92.2
7.3
0.5
Lewiston
resi-
dential
89.1
8.6
2.3
Lewiston
com-
mercial
68.1
28.2
3.7
West
Clarkston
80.5
16.9
2.6
Clarkston
com-
mercial
78.6
18.9
2.5
SEASONAL VARIATIONS
General
Each season has its own characteristic effect on the ability of the
atmosphere to accept and dispose of pollutant emissions and also,
therefore, on the outward manifestation of air pollution.
During summer, conditions are favorable for inversion breakup
and fumigations: light air flow, stable nights, and unstable days
(which tend to occur with clear skies). Because of rapid heating
during summer, inversion breakup is rapid, producing large H2S
concentrations for periods of about 1/2 to 1 hour. Average concen-
trations are, however, smallest during the summer because of the
shorter periods of darkness when conditions are stable and the
generally good diffusion conditions during the day.
Fall produces somewhat fewer fumigations than summer. But
inversion breakup takes longer, large H2$ concentrations are pro-
duced during fumigations lasting from 1 to 2 hours. Average concen-
trations are greatest in the fall since light winds and greater fre-
quency of stagnating anticyclones produce poor over-all diffusion
conditions.
Evaluation of Air Quality - Chapter IV
75
-------
During winter the frequency of east winds is high, and winds, though
not as light on the average as during the fall, are frequently light through-
out the day. The frequency of stagnating anticyclones is high. Inversion
breakup fumigations do not occur as frequently as in either summer or
fall. High, short-term (about 2- to 3-hour) concentrations can be ex-
pected to occur frequently with near neutral atmospheric conditions.
Average H2S concentrations are only slightly smaller than during the
fall.
In the spring, light winds are less frequent than in summer or fall.
Inversion breakup fumigations can be expected to be more frequent than
during winter but less frequent than during summer or fall. Neutral
conditions may be expected to produce large E^S concentrations with
somewhat less frequency than in winter. Average concentrations are
greater than in summer but less than in fall or winter.
The Study Period
Since the period under study had higher wind speeds than normal
and higher frequencies of westerly winds than would be expected, it
was expected that frequencies of large E^S concentrations would be
generally lower than those normally occurring during this time of year.
The H2S concentrations were related very closely to the dispersion
and dilution of the pollutants by air movement in the valley. It was
generally true that smallest concentrations at all stations were observed
in the spring when gusty winds and a high degree of vertical mixing of
the air occurred. These conditions provided better ventilation for the
valley, and thus lowered pollution levels. Greatest concentrations were
observed in November and February, when the duration and the frequency
of inversions were most pronounced and produced conditions conducive
to pollution accumulation (Table 4-8). Again, the highest pollution levels
were noted at the valley stations directly in line with the major pollution
source and at the lower elevations, which were most susceptible to
frequent morning fumigations.
VARIATION BY DAY OF WEEK
With data from stations in the valley, variations of H2S concentra-
tions by day of week were studied. Friday had significantly larger
average concentrations than the other days (Table 4-9). It also had a
significantly higher frequency of concentrations 3 ppb or greater. Since
it is not likely that freak occurrences of weather conditions conductive
to pollution buildup exist on Fridays, it is concluded that the emissions
of H2S are greater on Fridays.
DIURNAL VARIATIONS
H2S concentrations showed no variation by time of day for Moscow
(Table 4-10); only background amounts were measured. Significant
daily peaks of pollution occurred at the two Clarkston stations from
about 0800 to 1000 and in the Lewiston commercial area from 1000 to
76 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
O
Table 4-8. MONTHLY VARIATION OF HYDROGEN SULFIDE CONCENTRATIONS
IN PARTS PER BILLION, BY AREA, FOR STUDY PERIOD
o
I
ff
Month
November
December
January
February
March
April
Average
Sampling station
Moscow
0.98
0.54
1.21
0.98
1.02
0.06
0.80
Lewiston
Orchards
1.9.1
1.67
1.43
1.01
0.73
0.46
1.21
Lewiston
residential
2.86
1.84
0.84
2.01
0.92
0.84
1.55
Lewiston
commercial
4.75
1.79
1.29
2.47
1.62
1.34
2.21
West
Clarkston
2.44
2.24
1.58
2.66
1.76
1.13
1.97
Clarkston
commercial
2.85*
1.90
1.72
2.41
1.77
1.26
1.81
a Note: November HgS concentration for Clarkston commercial is monthly average for
controlled temperature AISI Sampler at Clarkston Fire Station.
-------
1200. This morning peak of pollution was associated almost daily with
the breakup of inversions (Figure 4-21). With inversion breakup,
fumigation of the residential areas in the valley occurs (Table 4-10).
The apparent delay between peaks at the Lewiston and Clarkston stations
is due to two factors: (1) The north slope of the river valley is steepest
just north of Clarkston; and (2) the ground near Clarkston slopes down-
ward to the northeast, whereas the ground near Lewiston slopes down-
ward to the northwest. Both factors allow more rapid heating by the
morning sun over Clarkston, since solar heating is quicker where a
surface is more perpendicular to the sun's rays. Figure 4-22, graphing
the frequency of inversion breakup during the study period as determined
by the Post Office station and airport hydrothermograph records, shows
the same pattern as do the peaks of daily Hg S concentrations.
Table 4-9. VARIATION OF HYDROGEN SULFIDE
CONCENTRATIONS BY DAY OF WEEK IN THE VALLEY a
Day of
week
Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Average
concentration,
ppb
2.1
1.9
1.7
1.6
1.9
2.4
1.5
Number
of samples
> 3 ppb b
147
141
144
137
174
202
136
a Stations 4, 5, and 6 were used.
" Data from November 1 through April 25 were used,
providing 25 days of data for each day of the week.
RELATIONSHIP OF HYDROGEN SULFIDE CONCENTRATIONS TO
WEATHER PARAMETERS
Wind Speed
The frequencies of high and low wind speeds at the Post Office
station during periods with H2S concentrations of 3 ppb or greater were
observed to determine whether wind speed had any relation to large
concentrations of HgS. In addition, the frequency of high and low wind
speeds was determined without regard to H2S concentration. The fre-
quencies were then compared as ratios (Table 4-11). These ratios in-
dicate that, generally, large H2S concentrations occurred as frequently
78
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
o
13
I
o
I
Table 4-10. VARIATION OF HYDROGEN SULFIDE CONCENTRATIONS
BY HOUR OF THE DAY AND BY AREA, FOR STUDY PERIOD
Time of
sample
0000-0200
0200-0400
0400-0600
0600-0800
0800-1000
1000-1200
1200-1400
1400-1600
1600-1800
1800-2000
2000-2200
2200-2400
Hydrogen sulfide concentration, ppb
Moscow
0.8
0.8
0.8
0.8
0.8
0.8
0.8
0.8
0.8
0.8
0.8
0.8
Lewiston
Orchards
1.1
1.2
1.4
1.3
1.2
1.4
1.4
1.2
1.2
1.1
1.0
1.2
Lewiston
residential
1.1
1.0
1.3
1.2
1.7
2.5
2.7
1.9
1.6
1.4
1.3
1.2
Lewiston
commercial
1.6
1.5
1.6
1.9
3.3
4.4
3.3
1.9
1.7
1.5
1.7
1.6
West
Clarkston
1.6
1.7
1.8
2.3
3.2
2.7
2.3
1.8
1.6
1.4
1.5
2.0
Clarkston
commercial
1.4
1.3
1.6
2.1
3.2
2.4
2.2
1.7
1.5
1.4
1.5
1.3
-------
LEWISTON COMMERCIAL
0100 03000500 07000900 1100 1300 1500 1700 1900 2100 2300
TIME OF DAY
Figure 4-21. Hourly hydrogen sulfide concentrations
for selected areas during the study period.
•with winds greater than 3.4 mph as with lesser wind speeds. An ex-
ception was the Lewiston residential station, which had half again as
many light winds with large H2S concentrations as was expected from
the frequency of occurrence for the study period. Since lesser wind
speeds tend to allow higher effective stack heights and the plume from
the major source remains aloft, large I^S concentrations at ground
level would not be expected to be associated with light winds. Fumiga-
tion conditions, when the lower portion of the atmosphere becomes
unstable and reaches the plume aloft mixing it between the ground and
its previous level, generally have surface wind speeds between 3 to 7
mph. Fumigation seems to be the principal mechanism for producing
large concentrations at ground level.
80
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
Table 4-11. COMPUTED RATIO OF OBSERVED TO
NORMALLY EXPECTED FREQUENCIES OF HYDROGEN
SULFIDE POLLUTION WITH WIND SPEEDS, a
BY AREA, FOR STUDY PERIOD
Sampling
station
Lewiston
Orchards
Lewiston
residential
Lewiston
commercial
West
Clarkston
Clarkston
commercial
Ratios (R) b
Wind speed <3.4
mph
0.9
1.6
1.2
1.1
1.1
Wind speed > 3. 4
mph
1.2
0.7
0.9
1.0
0.9
a Post Office weather station.
R =
WT
i
Wj = Number of observations of wind speed in a given
category (i.e., above or below 3.5 mph) over the
study period.
= Total observations of wind speed in all (both)
categories over the study period.
Pi = Number of observations of wind speed in a given
category when hydrogen sulfide pollution was
measured at 3 ppb or greater.
Pt = Total of all observations of wind speed in all
(both) categories when hydrogen sulfide pollution
was measured at 3 ppb or greater.
Evaluation of Air Quality - Chapter IV
81
-------
12 -
0200 0400 0600 0800 1000 1200 1400 1600 1800 2000 2200 2400
TIME OF DAY
Figure 4-22. Estimated percent frequency of inversion
breakup by hour of day for study period.
Wind Direction
Ratios of frequencies of wind direction were also calculated from
the Post Office wind direction records. These are shown in Table 4-12.
Ratios in the northwest quadrant are generally high, probably because
(1) the Post Office winds generally shift to upvalley and up the south
slope prior to fumigations and (2) the Post Office station frequently
shows a northwest wind when the flow is from the southeast at the air-
port, which is presumably a result of the standing eddy in the lee of the
abrupt rise just south of the post office.
Episodes During Study Period
A study of the frequency of high levels of pollution greater than
10 ppb by area substantiates the findings of Table 4-7. The most severe
pollution was observed in November at most stations and was most
pronounced at the valley stations (Table 4-8). The Lewiston commer-
cial station showed 11 days in which I^S concentrations of 10 ppb or
greater were observed. During these 11 days, 24 samples, covering a
period of 48 hours, exceeded 10 ppb. The forecasting program of the
U.S. Public Health Service indicated a 48-hour stagnation period would
occur from November 7 to 9, 1961. I^S concentrations were relatively
low on the 7th, increased somewhat on the 8th, and reached peaks on the
9th. On the 10th, concentrations had diminished approximately to those
of the 7th. The maximum daily concentration, 14.4 ppb, was recorded
at the Lewiston residential station. The maximum 2-hour concentration,
51 ppb, occurred at this station November 9. Conditions conducive to a
second episode existed in late January and for the first 2 days of Feb-
ruary 1962, Although not as great as in November, H2S concentrations
82
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
GPO 81 6—920—7
-------
Table 4-12. COMPUTED RATIO OF OBSERVED TO NORMALLY
EXPECTED FREQUENCIES OF HYDROGEN SULFIDE
WITH WIND DIRECTION, BY AREA, FOR STUDY PERIOD
Wind
direction
N
NNE
NE
ENE
E
ESE
SE
SSE
S
SSW
SW
WSW
W
WNW
NW
NNW
Ratio (R) a
Lewiston
residential
station
0.42
0.72
0.24
0.31
2.38
0
0
1.00
1.79
2.08
0.47
1.10
2.29
5.56
3.25
0.37
Lewiston
commercial
station
1.12
1.44
0.79
0.39
0.31
0.36
0.58
2.00
1.19
0.69
0.99
0.28
0.51
0.31
2.17
1.73
West
Clarkston
station
0.92
0.83
0.35
1.28
3.15
0
0
0.31
0
0.33
0.30
0.26
0.48
2.04
1.36
2.21
Clarkston
commercial
station
1.36
1.26
0.96
1.02
1.03
0.27
0.43
0.25
0
0.52
0.24
0.21
0.76
2.09
2.16
2.50
R =
Pt
Where:
Dj = Number of observations of wind direction in a given category
(i.e., north, north-northeast, northeast, etc.) over the study
period.
DT = Number of total obervations of wind direction in all
categories over the study period.
Pj = Observations of wind direction in a given category when H2S
pollution was measured at ppb or greater.
Pt = Total observations of wind direction in all categories when
H2S pollution was measured at 3 ppb or greater.
Evaluation of Air Quality - Chapter IV
83
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of 24 to 26 ppb for 4 hours were observed at the three valley stations.
These maxima occurred on February 1, 1962.
Weather Associated With High Hydrogen Sulfide Concentrations
All 2-hour periods during January through April 1962 with ^S con-
centrations of 10 ppb or greater at any of five stations (81 periods) were
studied to determine the meteorological conditions associated with them.
(There were no concentrations 10 ppb or greater at station 2.) During
none of these periods were concentrations 10 ppb or greater at more
than three stations. During 60 periods, concentrations were >10 ppb at
only one station; during 16, at two; and during 5 at three (Table 4-13).
Forty- eight periods were associated with inversion breakup fumiga-
tions causing relatively large concentrations as the elevated stable plume
was mixed uniformly between the ground and its original height. During
the vertical mixing, the plume width increased but was still small enough
so that relatively large concentrations occurred between 0400 and 1600
Table 4-13. OCCURRENCE OF HYDROGEN SULFIDE
CONCENTRATIONS 10 ppb OR GREATER
Station No.
Time
0000-0200
0200-0400
0400-0600
0600-0800
0800-1000
1000-1200
1200-1400
1400-1600
1600-1800
1800-2000
2000-2200
2200-2400
3
Alone
1
1
1
1
1
1
2
1
9
4
Alone
1
1
3
5
1
1
12
5
Alone
1
3
2
4
4
4
1
1
2
22
6
Alone
1
1
2
2
2
2
1
2
3
1
17
60
3,4
1
1
1
3
3,5
1
1
4,5
1
1
2
4,6
1
2
1
4
5,6
1
1
4
6
16
3,4,6
1
1
4,5,6
1
1
1
1
4
5
84
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
and only beneath and near the centerline of the plume. Two of these
periods affected three stations, 15 affected two, and 31 affected only one.
Since stations 4, 5, and 6 were affected more frequently, it is likely
that the plume flowed from east to west along the rivers. There were,
however, 10 periods with a northeasterly component, and from the
observed concentrations, it appeared likely that the plume moved south
up the Snake River valley rather than west down it. The largest con-
centrations that occurred during fumigation conditions were 28 ppb at
station 3, 60 ppb at station 4, 43 ppb at station 6, and 44 ppb at station 6.
Neutral conditions were considered to have affected concentrations
during 22 periods; only one was affected during 18 periods, two during
1, and three during 3. These occurred between midmorning and late
afternoon. Probably somewhat stronger winds in the valley caused the
plume rise to be much lower than the 200 meters noted in photographs.
It is possible that the periods during evening hours were fumigations
due to the instability and mixing caused by the city. Of particular
interest were eight consecutive 2-hour periods (1800 on February 1 to
1000 on February 2, 1962). During three of these periods, concentra-
tions were >10 ppb at stations 4, 5, and 6. The highest concentrations
observed were: Station 4, 26 ppb; 5, 26 ppb; and 6, 33 ppb.
Winds at the airport were calm at 1800; between 0400 and 1000 were
from the south and south-southeast at 8 to 16 mph. Winds were not
observed at the airport from 1900 to 0400, but were estimated to be
from the south through southeast at 7 to 16 mph, and probably produced
a general east-to-west flow in the valley causing the plume from the
major source to move downvalley. Winds at the Post Office during this
entire period were from the north and north-northwest at 2 to 9 mph.
This was probably the result of an eddy that formed to the lee (in this
case north) of the rather abrupt rise just to the south of the Post Office
(Figure 4-23) and that helped lower the elevated plume moving down-
valley, which increased ground level concentrations of H2S.
Slightly unstable conditions were believed to cause three periods of
high concentrations (10, 17, and 25 ppb) between 1000 and 1600 at
Station 4 only.
On eight occasions Station 3 was the only one with 10-ppb or
greater concentrations, principally during the afternoon and evening
hours. This probably resulted from the elevated plume encountering
the south slope of the valley but remaining aloft or diffusing before
reaching the other station. Concentrations ranged from 10 to 26 ppb.
Although 10-ppb or greater concentrations frequently lasted only
during a 2-hour period at a given station, on numerous occasions con-
centrations remained great for up to five consecutive 2-hour periods.
Table 4-14 shows the frequency of persistence of 10>-ppb or greater
H2S concentrations at four stations. Table 4-15 gives the frequency of
different concentrations at 10 ppb or greater.
Evaluation of Air Quality - Chapter IV 85
-------
350
200
6
200
600 800 1,000 1,200 1,400 1,600 1,800 2,000
NORTH-SOUTH DISTANCE, meters
Figure 4-23. Expected wind structure in the vicinity of the
post office during February 1-2, 1962 (VERTICAL
SCALE EXAGGERATED 4 TIMES).
Table 4-14. FREQUENCY OF PERSISTENT PERIODS OF
HYDROGEN SULFIDE CONCENTRATIONS 10 ppb OR GREATER3-
Duration,
hr
2
4
6
8
10
Station
3
8
1
1
4
9
1
5
5
18
6
1
6
13
6
1
1
Two-hour average.
Estimation of H2S Concentrations During Periods of High Pollution
Potential
From photographs of the plume, it is estimated that with light
winds (1 to 2 meters per second ) the effective height of the major
source was 200 meters, presumably because of the buoyancy of the
effluent. An estimate of fumigation concentration of H2S beneath the
centerline of the plume was made by the formula from Gifford 14
Xf =
Q
86
AIR POLLUTION IN LEW1STON-CLARKSTON AREA
-------
Table 4-15. FREQUENCY OF OCCURRENCE OF HYDROGEN
SULFIDE CONCENTRATIONS 10 ppb OR GREATER a
H2S
concentration,
ppb
10-19
20-29
30-39
40-49
60-69
Station
3
9
5
4
15
7
3
1
5
21
11
1
2
6
18
9
4
1
a Two-hour average.
where Xf is the concentration in grams per cubic meter, Q is the source
strength in grams per second,o-^ris the horizontal standard deviation of
concentration in meters, /iis the mean wind speed in meters per second,
and H is the height in meters to which the elimination of the inversion
has extended. Estimates of I^S emission for the principal source were
made in Chapter III. Diffusion estimates were taken from Gifford; *5
the following assumptions were made: The plume has been moved from
the source by an average wind speed of 1 meter per second, the plume
is mixed uniformly in the vertical to a height of 250 meters above the
river, the plume prior to fumigation has been influenced by moderately
stable diffusion conditions, and the horizontal standard deviation of
plume concentration increases threefold during the fumigation process.
The resulting concentrations at Stations 4, 5, and 6, if each Station is
beneath the plume centerline, are as follows: Station 4, 65 ppb, dropping
to 10 ppb at a distance of 550 meters from the plume centerline; Sta-
tion 5, 30 ppb, dropping to 10 ppb at 900 meters; and Station 6, 40 ppb,
dropping to 10 ppb at 800 meters. No computations were attempted for
Station 3 because it is about 50 meters above the river and the model
used cannot easily allow for the elevation difference. The calculated
fumigation concentration would be smaller for wind speeds greater
than 1 meter per second and larger for mixing heights below 250 meters.
The greatest concentrations observed for 2-hour periods during fumiga-
tion conditions have previously been given as: Station 3, 28 ppb; 4, 60
ppb; 5, 43 ppb; and 6, 44 ppb. These were also the greatest concentra-
tions observed under any conditions during January through April.
By means of the Gaussian plume model, " at neutral dispersion
conditions, wind speed of 2.5 meters per second, and effective height of
emission of 100 meters, the concentration, if each station is beneath
the centerline, is calculated as: Station 4, 47 ppb, lessening to 10 ppb
at a distance of 320 meters acrosswind from the plume centerline;
Station 5, 25 ppb, lessening to 10 ppb at 550 meters; and Station 6, 37
ppb, lessening to 10 ppb at 520 meters. The greatest observed 2-hour
Evaluation of Air Quality - Chapter IV
87
-------
concentrations during neutral conditions were; Station 4, 26 ppb; 5, 26
ppb; and 6,33 ppb. This is in close arrangement with the above com-
putations.
By means of the Gaussian plume model, and on the assumption of
dispersion conditions, wind speed of 2.5 meters per second, and effec-
tive height of 100 meters, the concentration, if each station is beneath
the centerline, is calculated as: Station 4, 29 ppb, lessening to 10 ppb
at a distance of 390 meters from the plume; Station 5, 7 ppb; Station 6,
12 ppb, lessening to 10 ppb at 280 meters. The greatest concentration
observed during unstable conditions when one station had concentra-
tions 10 ppb or greater were: Station 4, 25 ppb; Station 5, 3 ppb;
and Station 6, 9 ppb.
Comparative Studies of Atmospheric Hydrogen Sulfide
Concentrations
A well-established and often-used wet chemical test, the methylene
blue procedure (see Appendix), substantiated the validity of H^S con-
centrations obtained by the treated-filter tape samplers. For three
2-week periods, one each in November, January, and April, continuous
2-hour air samples were collected and analyzed at the Clarkston Fire
Station by the two methods; thus 42 days of sampling with 12 daily
samples produced about 500 methylene blue samples for comparison.
Although the principal point of interest was the correlation of
results between the methylene blue procedure and the "standard"
treated-filter tape samplers, two additional samplers were operated
for comparison. For one, the air was passed through a long, spiralled,
glass tube submerged in a constant-temperature water bath to produce
an air temperature of approximately 70°F at the sampler. The second
sampler differed from the "standard" samplers in the type of vacuum
pump employed; it used a diaphragm pump, which produces a somewhat
variable flow rate at the filter tape.
November was the only period during which a significant number of
air concentrations (36) greater than 2 ppb were recorded, amounting
to 20 percent of the November samples. January showed two and April
four (Table 4-16). Because of a shortage of instruments, the standard
filter tape sampler was not operated in November at the control station.
When the readings of the standard sampler, the controlled-tempera-
ture sampler, and the diaphragm pump sampler were compared with
the results of the methylene blue test, the standard and controlled-
temperature tape samplers were within +1 ppb of the methylene blue
results 85 and 84 percent of the time (Table 4-17). The diaphragm
pump tape sampler was within +1 ppb on 63 percent of the samples.
ADR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
Table 4-16. FREQUENCY DISTRIBUTION OF H2S CONCENTRATIONS
OBTAINED BY THE METHYLENE BLUE PROCEDURE
Concentration,
ppb
0
1
2
3
4
5
6
7
8
9
>10
Occurrences
November
23
101
16
11
7
4
5
2
3
2
4
178
January
123
26
2
1
1
0
0
0
0
0
0
153
April
113
41
8
2
0
2
0
0
0
0
0
166
TAPE FADING
was determined from the treated-filter tapes by use of a photo-
meter (see Appendix). The light transmittance through the reacted
darkened tape was recorded and interpreted from a calibration curve in
terms of I^S in parts per billion. The field practice of removing the
tapes from the machine after about 2 weeks of operation for reading on
the photometer raised questions concerning the possibility of a darkened
spot fading with time. As a general rule, tapes were removed from the
machines and accumulated until a sufficient number was collected to
warrant sustained use of the photometer. As a result, some tapes were
read several weeks after collection. If fading of the spots (i.e., lighten-
ing of the lead sulfide spot collected) had occurred, light transmittance
would have been higher and the measured I^S concentrations lower
than the true value.
A brief laboratory check of tape fading was conducted on two
separate tapes collected in late March and early April. A total of 336
samples on the tapes were reread. A time lapse of from 65 to 88 days
had occurred at the time of the final reading. Initial readings had been
made from 7 to 26 days after collection. Initial readings of the samples
checked showed 298 to be above 90 percent transmittance and only 38
samples below 89 percent transmittance (Table 4-18). Of the 336
samples, 122 showed identical transmittance readings, 116 showed
Evaluation of Air Quality - Chapter IV
89
-------
Table 4-17. COMPARISON OF TREATED-FILTER TAPE SAMPLER
RESULTS WITH METHYLENE BLUE PROCEDURE RESULTS
Tape
sampler
compared
Standard
treat ed-filter
tape sampler
Controlled-
temperature
tape sampler
Diaphragm
pump tape
sampler
Month
November
January
April
November
January
April
November
January
April
Number of
methylene
blue samples
compared
153
166
319
(total)
178
153
166
497
(total)
178
153
166
497
(total)
Deviation of results from
methylene blue procedure,
% of samples
0 ppb
41
61
49
(avg)
27
50
61
45
(avg)
20
7
66
32
(avg)
Within ±1 ppb
90
77
85
(avg)
75
95
85
84
(avg)
59
36
91
63
(avg)
increased transmittance (spot faded), and 98 showed decreased trans-
mittance (spot darker). Although only a few samples in the low trans-
mittancd range were evaluated, no apparent difference was noted in the
average amount of increase or decrease between these and the lightly
spotted samples (i.e., 90 to 100% transmittance).
It is concluded that fading of the collected lead sulfide is not a prob-
lem when the exposed tapes are sealed in a relatively airtight container,
which was the handling procedure employed throughout the study.
To evaluate the influence of changing line voltage on readings
obtained with the photometer, several tapes were read with and without
90
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
Table 4-18. COMPARISON OF INITIAL AND FINAL LIGHT
TRANSMITTANCE READINGS FOR
EVALUATING TAPE FADING
Initial
light
trans-
mittance,
%
90-100
80-89
70-79
60-69
50-59
<50
Total
Difference in light transmission
No
dif-
ference
No. of
samples
117
1
2
0
0
2
122
Increase
(faded)
No. of
samples
96
14
5
0
0
1
116
Average
increase,
%
3
6
4
0
0
5
Decrease
(darkened)
No. of
samples
85
2
2
4
3
2
98
Average
decrease,
%
3
4
3
3
3
2
Total
298
17
9
4
3
5
336
a constant-voltage regulator in the line ahead of the photometer. Al-
though occasional fluctuations in line voltage were noted, similar read-
ings were obtained with both procedures.
CONCLUSIONS REGARDING H2S
Atmospheric hydrogen sulfide (I^S) concentrations were determined
at four sampling sites in Lewiston, two in Clarkston, and one in Moscow
(control site) with impregnated filter paper sequential samplers.
Samples were collected over 2-hour periods for a 6-month period
(November-April). Atmospheric H2S concentrations varied directly
with the distance from the pulp mill. Greatest concentrations generally
occurred between 0800 and 1200, coinciding with the time of inversion
breakups, which result in ground fumigation. Little or no diurnal
variation was observed at the control station, indicating that only back-
ground H2S concentrations were present. The maximum 2-hour con-
centration measured was 60 ppb, which was recorded at the Lewiston
commercial sampling site. The average 2-hour concentration for 6
months at this station was 2.2 ppb, compared with 0.80 ppb at the
Moscow control site.
The results obtained with treated-filter paper samples compared
favorably with samples collected in a wet scrubber and analyzed by
the methylene blue method. Investigation of the stability of the lead
Evaluation of Air Quality - Chapter IV
91
-------
sulfide stains produced on the filter paper samples revealed little loss
of sample in approximately 3 months when the exposed tapes were seal-
ed in a relatively airtight container.
SULFUR DIOXIDE
Sulfur dioxide (SO2) is an irritating and toxic gas with a taste thres-
hold of 0.3 ppm and an odor threshold of 3.0 ppm. 16 The State of
California selected an SO2 concentration of 0.3 ppm for an 8-hour period
as its standard for ambient air quality. 1? For periods of 1 hour, 1 ppm
was selected. Sensitive varieties of certain plants show damage at 0.04
ppm for 7 hours. 18 A major source of SO2 is the combustion of fuel
(see emission inventory). The SO2 emission from this source depends
on the sulfur content of the fuel and to a lesser degree the method of
firing, but the bulk of the sulfur is emitted after oxidation as SO2. At
times industrial process emissions can also be a major source of SC>2.
Concentrations of this gas in ambient air also were of interest since
large concentrations caused interference with the wet chemical proce-
dure used for measuring H2S. One investigator demonstrated that when
SO2 concentrations were approximately 100 times those of H2S, the
methylene blue procedure gave low and erratic results. 19 The concen-
trations used in his experiment were believed to range from 0.5 to 60
ppm.
In this study, 2-hour SO2 samples were collected and analyzed con-
tinuously for approximately 2-week periods in November, January, and
April by use of the West-Gaeke procedure (see Appendix). 20 A total of
512 samples - 191 in November, 153 in January, and 168 in April - were
analyzed. During November, 362 values ranged from 0 to 15 ppb
(0.015 ppm), with an average of 3.2 ppb; during January, from 0 to 25
ppb, with an average of 4.7 ppb; and during April, from 0 to 11 ppb,
with an average of 1.1 ppb. The greater concentrations were observed
during the colder periods, which indicated that fuel burning for space
heating is a primary source of SO2 in the area. Further, a check of
meteorological conditions in April reveals the almost daily occurrence
of gust winds. Thus, with increased ventilation to dilute the pollutants,
lesser concentrations would be expected.
The greatest average concentration for any one sampling day
occurred on November 20, 1961, with an average of the 12 samples
measuring 9 ppb. The maximum daily average in January was 7 ppb
and in April, slightly less than 3 ppb (Table 4-19). Concentrations were
observed to be maximum at 0900 for both November and January
(Table 4-20). This agrees with meteorological data, which showed
inversion breakup occurring in the late midmorning hours. E^S con-
centrations showed a similar maximum from about 0900 to 1100.
In view of the small concentrations of SO2 observed, no problem at
the present time is believed to exist, although additional sources of SO2
or changes in the fuel pattern could conceivably produce sufficient con-
92 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
Table 4-19. AVERAGE DAILY SO2 CONCENTRATIONS
November
Date
11/4
11/5
11/6
11/7
11/8
11/9
11/10
11/11
11/12
11/13
11/14
11/15
11/16
11/17
11/18
11/19
11/20
Concen-
tration,
ppb
2
3
3
2
3
4
2
2
2
3
2
3
3
6
5
4
9
January
Date
1/7
1/8
1/9
1/10
1/11
1/12
1/13
1/14
1/15
1/16
1/17
1/18
1/19
Concen-
tration,
ppb
3
2
7
6
5
6
6
7
2
7
3
5
5
April
Date
4/15
4/16
4/17
4/18
4/19
4/20
4/21
4/22
4/23
4/24
4/25
4/26
4/27
4/28
Concen-
tration,
ppb
1
3
2
2
<1
<1
1
2
1
<1
-=:l
<\
-=1
<1
centrations to pose a problem under adverse weather conditions.
Secondly, at the concentrations measured, no interference was likely
with the methylene blue method of analysis for H^S.
CONCLUSIONS REGARDING SO2
Twelve 2-hour atmospheric sulfur dioxide (802) samples were
collected and analyzed daily during 2-week periods in November,
January, and April. The greatest 24-hour concentration (9 ppb) occurred
in November. The greatest 2-week average concentrations (5 ppb)
occurred in January, indicating that fuel burning for space heating is
a primary source of SO2 in the area. In view of the small atmospheric
concentrations present, SO2 is not considered to be a major air pol-
lutant in the area.
Evaluation of Air Quality - Chapter IV
93
-------
Table 4-20. VARIATION OF SULFUR DIOXIDE
CONCENTRATIONS WITH TIME OF DAY
Time period
0000-0200
0200-0400
0400-0600
0600-0800
0800-1000
1000-1200
1200-1400
1400-1600
1600-1800
1800-2000
2000-2200
Concentration, ppb
November
3
2
3
3
6
3
3
2
3
4
3
January
3
4
4
7
9
1
3
6
2
6
6
April
1
1
2
2
1
<1
1
<1
0
<1
2
ODORS
GENERAL
Modern man lives amid> diverse odors and odoriferous materials.
Although the total number of outright stenches has decreased with the
decline of tanning, candlemaking, and other noxious and offensive
operations, man has substituted diversity for strength. This diversity
may be attributed in part to industrial operations, though many other
community activities may also result in odors. The response to any
given odor is subject to individual variation, and it may or may not be
considered objectionable.
Man's perception of odors is not as acute as that of some lower
animals, though some individuals, through training or natural ability;,
are acutely sensitive to slight differences in odors. In any one com-
munity, however, sensitivity should be normally distributed, from ex-
ceptional to nil. 21
The problem of precisely defining an offensive odor is difficult. An
odor may be pleasant to one and offensive to another person because of
psychological factors that may cause unpleasant association with the
odor. An objectionable odor cannot be defined as one that is offensive
94
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
to all individuals exposed to it, since there will always be a few who will
be blissfully unaware of even the most fetid stench. 22
A working definition of an offensive odor may be: an odor that is
objectionable to the majority of healthy persons exposed to its olfactory
action.
CRITERIA FOR ODOR SURVEYS
An accurate determination of the distribution of odors in this area
cannot be readily achieved by an investigation of each complaint. Instead,
a systematic odor survey is needed to: (1) provide community-wide
coverage, (2) establish areas most severely affected, (3) determine when
and how often people experience odors, and (4) provide results that can
convince offenders that they are creating an air pollution problem.
METHODS OF ODOR SURVEYS
Techniques for evaluating community odor problems normally in-
clude: surveys by many untrained observers, 26, 27 odor evaluations
by trained observers aided by mechanical diluting devices, 21,25,28,29
or chemical evaluations. 30-34 Trained observers can gather more
detailed information, but usually, because they are so few, cannot
achieve the wide area coverage possible with a survey technique. Un-
trained observers are usually unable to make detailed observations, but
the total of observations is large, and the area coverage is wide.
METHODOLOGY OF THIS ODOR SURVEY
Objectives: The objectives of this survey were to determine:
1. The major odor types in the area.
2. The areas most severely affected and the type of odor involved.
3. The season, day of week, and time of day when odors are most
often observed.
4. The variables that may influence observer response, e.g., human
and meteorological variables.
The first three involve the practical aspects of the odor problem, where-
as the fourth involves information useful both for the present study and
future surveys.
Selection of Observers
One of the first problems was selection of observers. There were
two possibilities: use of a few highly trained observers or use of many
observers with little or no training. Both methods were used. The
trained personnel were selected from the Clarkston and Lewiston city
engineering departments. Two men from each city made odor observa-
tions using scentometers to help establish odor strength at various
points in the community.
Evaluation of Air Quality - Chapter IV 95
-------
The untrained observers were selected from high school students
in the two communities; somewhat over 100 students participated during
each phase of the study. The procedure used to evaluate observers and
details of the method for conducting odor sensitivity tests are outlined
in Appendix A.
Factors Influencing Odor Sensitivity
One would expect a group of individuals collected at random to have
degrees of sensitivity to odors that could be graphed along the familiar
bell-shaped curve. If all the groups are more or less sensitive than
average, however, the results reflect this. Another complicating factor
is that an individual's sensitivity to odors varies from day to day. It
was found, however, that day-to-day variations do not affect the results
of the scentometer. 21
Several factors are involved in an estimation of the variation of
individual sensitivity:
1. The sense of smell is rapidly fatigued.
2. Fatigue for one odor does not necessarily affect the
perception of dissimilar odors, but does affect the
perception of similar odors. 22
3. Responses to odors are not completely objective since
phychological responses vary in different observers.
4. Some persons are extremely sensitive, whereas others
are incapable of smelling an odor. Age seems to affect
sensitivity, with a maximum at puberty and a decrease
with age.
5. Many observers have reported 22,23 that odors become
stronger in fog. The effect of temperature on odor has
been noted, but is linked to the formation of fog.
Meteorological factors have an influence on the reported levels of
odors, 23 with wind speed and inversion occurrence determining the
dilution of odors in the air. Topography also may affect the transport
of odors and may cause pockets of trapped odorous air that persists.
The problem of odor fatigue is impossible to eliminate. The com-
munity under study would be considered highly odorous by newcomers
to the area. Within an hour of arrival, however, a marked reduction in
odor, caused by fatigue, is noticeable. One can reverse the fatigue
effect by traveling out of the valley for several hours, but the fatigue
returns soon after re-entry.
It is impossible to estimate how much resensitization to odors the
valley residents undergo during periods of low odor concentration or
during periods when ventilation of the valley is sufficient to dilute the
odorants present. No attempt was made, therefore, to measure or
estimate the possible effects of fatigue on the response. It would seem
that persons living in Lewiston Orchards and possible Clarkston Heights
96 AIR POLLUTION IN LEWIS TON-CLARKSTON AREA
-------
§
a
>
o
Table 4-21. COMPARISON OF THE TOTAL POSSIBLE AND ACTUAL OBSERVATION
RESPONSES BY SURVEY PERIODS AND AREAS
Survey period
and area
November total
Clarkston
Clarkston Heights
Lew is ton
Lewiston Orchards
April total
Clarkston
Clarkston Heights
Lewiston
Lewiston Orchards
Number of
students
120
51
7
32
30
110
37
6
37
30
Possible
observations a
5,040
2,142
294
1,344
1,260
4,620
1,554
252
1,554
1,260
Actual
observations
3,817
1,650
289
943
935
3,169
1,167
204
1,072
726
Percent response
(or 1 nn -, actual ,
U 10° xpossible *
75.7
77.0
98.3
70.2
74.2
68.6
75.1
81.0
69.0
57.6
a Possible observations = number of students x 14 days x 30 observations per day.
CO
~3
-------
face the problem of adapting to the odors in the valley every morning as
they travel to work.
To eliminate some of the psychological factors in odor response, the
student observers were asked to note all odors whether pleasant or un-
pleasant. They were also asked to note whether the odor was strong or
faint, and to describe it in their own words. Classifications of observed
odors (Table 4-23) were made upon the basis of descriptions reported by
the observers.
Conduct of the Surveys
Odor surveys were made from November 7 to November 20, 1961,
and from April 15 to April 28, 1962. The students made three observa-
tions daily: at approximately 0700, 1600, and 2000. The trained observers
had specified routes thoughout the area, with approximately 10 sampling
stops. The trained observers also released small helium-filled balloons
to determine the wind direction and to estimate the wind speed.
The student observers recorded their observations on cards (Appen-
dix A). Instructors in the two high schools collected the cards each day.
The responses in both surveys are shown in Table 4-21. The poorest
response was 57 percent in April, but even this figure was considered
good.
The sex and grade level of the students are shown in Table 4-22.
The girls were more conscientious observers in both studies, and fresh-
men and sophomores were more conscientious than juniors and seniors.
Table 4-22. COMPARISON OF THE AVERAGE NUMBER OF
OBSERVATIONS WITH THE SEX AND GRADE
LEVELS OF THE STUDENT OBSERVERS
FOR EACH SURVEY PERIOD
Total number of
student observers
Males
Females
Freshman and
Sophomores
Juniors and
Seniors
November
Number of
observersa
120
50
70
78
31
Average
observations
per student
32
23
33
35
27
April
Number of
observers
110
44
66
96
14
Average
observations
per student
29
28
29
30
23
a The high school grade is unavailable for 11 student observers in the
November survey.
98
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
GPO 81 6—920—8
-------
Table 4-23 shows the odor classifications used. Type 0 odors,
flowers, were not used in November but were used in April. The
students were not told to report by odor type, to prevent any possibility
of influencing the results.
Table 4-23. CLASSIFICATION OF ODORS FOR
THE STUDENT ODOR SURVEY
Odor type
Observed odor as described by students
2
3
4
5
6
7
8
9
0
None
PFI (Potlatch Forest, Incorporated, mill),
cabbage, rotten eggs
Smoke, wood smoke
Burning leaves
Wet grass, musty
Gasoline, oil, exhaust, road tar
Rendering plant, rotten flesh
Rubbish, burning trash
Animal odors
Miscellaneous odors
Flowers
No odor observed
MAJOR ODOR PROBLEMS
By Area
The frequency distribution of responses by area and study period is
shown in Table 4-24. Approximately 30 percent of the total responses
involved some type of odor, and about 10 percent involved Type 1 odors
of either faint or strong intensity. Tables 4-25 and 4-26 show the
distribution of the positive odor responses for the November and April
studies respectively. Since the pulp mill odors represent the largest
single nuisance odor category, analysis was confined largely to this
type.
Analysis of variance procedures was used to establish the presence
of significant differences in the pulp mill odor responses for each area.
Since the total number of students responding on any given day varied,
the proportion of positive responses to the total responses for that day
was used rather than absolute numbers of positive responses. Ninety-
five percent confidence levels were used throughout the analysis.*
* See Appendix C
Evaluation of Air Quality - Chapter IV
99
-------
o
o
Table 4-24. DISTRIBUTION OF ODOR RESPONSES BY SURVEY PERIOD AND AREA
fa
S
a
H
O
o
£
fa
CO
I
fa
Survey period and
area
November total
Clarkston
Clarkston Heights
Lewiston
Lewiston Orchards
AprU total
Clarkston
Clarkston Heights
Lewiston
Lewiston Orchards
Grand total
Total
observations
3,817
1,650
289
943
935
3,169
1,167
204
1,072
726
6,986
No
odor
2,489
888
141
721
739
2,476a
907
157
845
567
4,965
Positive odor response
Total
1,328
762
148
222
196
693
260
47
227
159
2,021
Faint
900
502
96
149
153
510
183
31
176
120
1,410
Strong
428
260
52
73
43
183
77
16
51
39
611
Type 1
Total
442
238
45
107
52
233
134
5
63
31
675
Faint
276
139
30
70
37
165
85
4
52
24
411
Strong
166
99
15
37
15
68
49
1
11
7
234
a "No odor" for the April survey includes responses to Type 0 (flowers) odors.
-------
The results show a significant difference among the areas. In
November, the percent response of Lewiston students to pulp mill odors
was significantly greater than the average, while that of all the others
was lower than average. In April, the positive responses in Clarkston
were greater than average, while all others were lower than average.
There was no significant difference between individual days during either
of the study periods.
Odors from burning leaves (Type 3) did not vary significantly in the
four areas. Similarly, the odors from burning wood (Type 2) showed no
variation. The burning rubbish odor (Type 7) was, however, reported
significantly more often in November in both Clarkston and Clarkston
Heights, which indicated that openly burning trash dumps are a localized
problem in the Clarkston area.
By Time
Since there was a definite peak of I^S concentrations in the morning,
the possibility of a greater frequency of pulp mill odor responses in the
morning was investigated. For both study periods, the morning res-
ponse to pulp mill odors was significantly greater than the average.
The other type odors had a somewhat different distribution by time
(Table 4-27). Burning wood, burning leaves, and burning rubbish all
elicited peak odor responses in the afternoon. Although these odors
affect the entire region to some degree, they do not behave as the pulp
mill odors. Emissions from burning wood, leaves, and rubbish are
basically ground level, and are not caught in the inversion nor dropped
at breakup since an inversion usually does not occur during the day.
Based on the responses to all odor types, there was no difference
between the two study periods, except for a significant difference be-
tween November and April in pulp mill odor responses in the Lewiston
area only.
ODOR PERCEPTION VERSUS HUMAN VARIABLES
General
Several possible human variables were studied to determine whether
they affected the results.
Sex Differences
It has been reported in the literature that females are more sensi-
tive than males to odors. A comparison of the sensitivities of the girl
respondents versus the boys showed that there was no significant dif-
ference for either study. The data for this study can be used, therefore,
without regard to the sex of the observer.
Evaluation of Air Quality - Chapter IV 101
-------
o
to
Table 4-25. FREQUENCY OF POSITIVE ODOR RESPONSE BY AREA AND
ODOR TYPE - NOVEMBER
Odor type
1
2
3
4
5
6
7
8
9
Total
Clarkston
51 students
Positive
responses
238
228
92
41
23
12
66
19
43
762
Total
positive
response, %
31.2
30.0
12.1
5.4
3.0
1.6
8.6
2.5
5.6
100.0
Clarkston
Heights
7 students
Positive
responses
45
41
8
5
4
8
12
11
14
148
Total
positive
response, %
30.4
27.7
5.4
3.4
2.7
5.4
8.1
7.4
9.5
100.0
Lewiston
32 students
Positive
responses
107
76
19
3
3
1
5
0
8
222
Total
positive
response, %
48.2
34.2
8.6
1.3
1.3
0.5
2.3
0.0
3.6
100.0
Lewiston
Orchards
30 students
Positive
responses
52
78
22
11
5
2
12
8
6
196
Total
positive
response, %
26.5
39.8
11.2
5.6
2.6
1.0
6.1
4.1
3.1
100.0
t-1
t-1
w
H
O
2
n
i
-------
O
Table 4-26. FREQUENCY OF POSITIVE ODOR RESPONSE BY AREA AND
ODOR TYPE - APRIL
Odor type
1
2
3
4
5
6
7
8
9
Total
Clarkston
37 students
Positive
responses
134
28
7
2
4
6
42
5
32
260
Total
positive
response, %
51.6
10.8
2.7
0.8
1.5
2.3
16.2
1.9
12.3
100.00
Clarkston
Heights
6 students
Positive
responses
5
14
0
7
0
0
5
2
14
47
Total
positive
response, %
10.6
29.8
0.0
14.9
0.0
0.0
10.6
4.3
29.8
100.0
Lewiston
37 students
Positive
responses
63
39
4
12
28
1
10
5
65
227
Total
positive
response, %
27.7
17.2
1.8
5.3
12.3
0.4
4.4
2.2
28.6
100.0
Lewiston
Orchards
30 students
Positive
responses
31
41
10
9
4
1
4
12
47
159
Total
positive
response, %
19.5
25.8
6.3
5.7
2.5
0.6
2.5
7.5
29.6
100.0
o
I
CD
O
GO
-------
Table 4-27. PERCENT DISTRIBUTION OF POSITIVE
RESPONSES TO SELECTED ODORS BY TIME
OF DAY FOR EACH SURVEY PERIOD
Observed
odor
type
Total
positive
responses a
1
2
3
7
November
0700
35.0
42.0
20.4
12.8
25.8
1000
32.5
29.0
46.9
62.4
43.3
2000
32.5
29.0
32.5
24.8
30.9
April
0700
33.3
45.5
18.0
14.3
23.1
1000
33.4
26.6
35.3
57.1
52.3
2000
33.3
27.9
46.7
28.6
24.6
a Odors of flowers (Type 0) were not used in this comparison.
Influence of Colds
A commonly held view is that persons with a cold cannot perceive
odors as well as those without colds. To test this hypothesis, data from
the sensitivity tests given in April were analyzed with regard to colds
as a variable. The analysis showed that there was no significant differ-
ence in sensitivity between students who reported having colds and those
who did not. This variable then had no statistical effect on the data.
Sensitivity Differences
Since H2S can anesthetize the odor-sensing organs, residents of
areas receiving high concentrations of this pollutant may temporarily
lose their ability to smell. It is possible, then, that the sensitivity of
the two groups as a whole would be different and would affect the response
from each area. An analysis of variance procedure was used to test for
significant differences in sensitivity. The results show that, as mea-
sured by the sensitivity tests, there was no difference between the odor
sensitivities of students in Clarkston and those in Lewiston. Results
from each area can, therefore, be compared.
Conclusions Regarding Odors
An odor survey was conducted in the Lewiston-Clarkston area dur-
ing 2-week periods in November and April with an observer corps of
approximately 100 high school students. Odor observations were made
at three specified times daily.
104
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
The data showed that pulp mill odors represent the largest single
nuisance category. The percentage of positive pulp mill odor responses
was highest in Lewiston during November and highest in Clarkston in
April. The number of reports of burning leaves or wood did not vary
significantly between areas. Odors attributed to open trash burning
were reported more frequently in the Clarkston area in November,
indicating a localized problem. Pulp mill odors were reported more
frequently in the morning. Odors from the burning of wood, leaves, and
rubbish were reported more frequently in the afternoon.
SUMMARY
The evaluation of air quality included measurement of ambient
concentrations of suspended particulate matter, hydrogen sulfide, and
sulfur dioxide at five sampling stations in the Lewiston-Clarkston area,
and at a control station in Moscow, Idaho. Visual and photographic
observations were used to measure visibility reduction. Odor surveys
were conducted in the two communities in November and April.
REFERENCES
1. Wright, R.H. The reduction of odors from kraft pulp mills.
Technical Bulletin #27. British Columbia Research Council,
Vancouver, Canada. 1961.
2. Smith, A.F., Jenkins, D.G., and Cunningworth, B.C. Measurement
of trace quantities of hydrogen sulfide in industrial atmospheres.
J. Appl. Chem., 11:317-29. Sept. 1961.
3. Moncrieff, R.W. The Chemical Senses. John Wiley and Sons, Inc.,
New York, N.Y. 1946.
4. Ryazanov, V.A. Limits of Allowable Concentrations of Atmospheric
Pollutants, Book 1 (1952 OTS #59-21173). Translated by B.S.
Levine. U.S. Department of Commerce, Office of Technical
Services, Washington 25, D.C.
5. DallaValle, J.M., McCord, C.P., and Witheridge, W.N., Odors,
Physiology and Control. McGraw-Hill Book Co. New York, N.Y.
1949.
6. Patty, F.A. Industrial Hygiene and Toxicology, Vol. 2. Interscience
Publishers, Inc. New York, N.Y. 1949.
7. Stern, A.C., editor. Air Pollution, Vol. 1 & 2. Academic Press,
New York, N.Y. 1962.
Evaluation of Air Quality - Chapter IV 105
-------
8. Lynn, C., and Elsey, H.M. Trans. Amer. Inst. Elect. Enginrs.,
68:106. Parti. 1949.
9. California State Board of Public Health. California Administrative
Code Title 17, Chapter 5, Sub-chapter 5, Article 1. Standards for
Ambient Air Quality. Scaramento, California. March 16, 1962.
10. Nonhebel, G. Recommendations of heights for new industrial
chimneys. J. Inst. Fuel., 33:479. Oct. 1960.
11. Lucas, D.H. Discussion of paper by G. Nonhebel before Institute of
Fuel. J. Inst. Fuel., 33:497. Oct. 1960.
12. Singer, LA. The relationship between peak and mean concentrations.
J. Air Poll. Cont. Assoc., 11:336. July 1961.
13. Sensenbaugh, J.D., and Hemeon, W.C.L. A low cost sampler for
measurement of low concentration of hydrogen sulfide. Air Repair,
4:5. May 1954.
14. Gifford, F.A. Atmospheric dispersion calculations using the
generalized Gaussian plume model. Nuclear Safety, 2:56-59. Sept.
1960.
15. Gifford, F.A. Use of routine meteorological observations for
estimating atmospheric dispersion. Nuclear Safety, 2:47-51. Sept.
1960.
16. Sax, N.I. Handbook of Dangerous Materials. Reinhold Publishing
Co., New York, N.Y. 1961. p. 1146.
17. California Department of Public Health. Technical Report of
California Standards for Ambient Air and Motor Vehicle Exhaust.
Berkeley, California. Sept. 1960.
18. Weisburd, M.I. Air Pollution Control Field Operations Manual.
PHS Publication Number 937. U.S. Government Printing Office,
Washington 25, D.C. 1962.
19. Smith, A.F., Jenkins, D.G., and Cunningworth, D.E. Measurement
of trace qualities of hydrogen sulfide in industrial atmospheres.
J. Appl. Chem., 11:317-29. Sept. 1961.
20. West, P.W., and Gaeke, G. C. Fixation of sulfur dioxide as dis-
sulfitomercurate and subsequent colorimetric estimation. Anal.
Chem., 28:1816-19. Dec. 1956.
21. Huey, N.A., Broening, L.C., Jutze, G.A., and Gruber, C.W. Objective
odor control investigations. J. Air Poll. Control Assoc., 10:441-46.
Dec. 1960.
22. Moncrieff, R.W., The chemical senses, 2nd Edition. L. Hill,
London. 1951.
106 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
23. Kenneth, J.H. Odors. Psychological Review, 37:XXX. 1927.
24. McCord, C.P., and Witheridge, W.N. Odors, Physiology and Control,
1st Edition, McGraw-Hill Book Company. New York, N.Y. 1949.
25. Gruber, C.W., Jutze, G.A., and Huey, N.A. Odor determination
techniques for air pollution control. J. Air Poll. Control Assoc.,
10:327. Aug. 1960.
26. Stalker, W.W. Defining the odor problem in a community. Am. Ind.
Hyg. Assoc. Journal, 24:600-605. Nov.-Dec. 1963.
27. Heller, A.N., Kandiner, H.J., Reiter, W.M., and Cohen, M. The
odor survey - a tool for air pollution control. Air and Water
Pollution Abatement Conference, Mfg. Chem. Assoc. March 1959.
28. Nader, J.S. An odor evaluation apparatus for field and laboratory
use, Amer. Lid. Hyg. Assoc. J., 19:1. Feb. 1958.
29. Byrd, J.F. Demonstration syringe odor measurement technique.
Proc. of Metro. Cincinnati Conf. on Air Poll. Control, Oct. 1956.
30. Crocker, B.C., and Sjostrom, L.B. Odor detection and thresholds.
Chem. & Eng. News, 27:1922. 1949.
31. Matheson, J.F. Olfactometry, its techniques and apparatus. J. Air
Poll. Control Assoc., 5:167. 1955.
32. Wenzel, B.B. Techniques in olfactometry: a critical review of the
last 100 years, Psychology Bull, 45:231. 1948.
33. Wenzel, B.B. Practical applications of olfactometry, Proc. Sci.
Sec. of the Toilet Goods Assoc., 14:11. Dec. 1950.
34. Turk, A. Appraisal of Odor Problems, Air Repair, 4:55. Aug.
1954.
Evaluation of Air Quality - Chapter IV 107
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CHAPTER V. SOME EFFECTS OF AIR POLLUTION
DETERIORATION OF MATERIALS
People are accustomed to the changes in their surroundings
caused by wind, rain, and other natural forces, but deterioration of
man-made products caused by these forces and by atmospheric pollu-
tion is not obvious. Gaseous, liquid, and particulate byproducts of
man's industry are vented to the atmosphere and poured down the
sewer. Byproducts of combustion from home heating and automobile
operation pass into the atmosphere to add to the "witches brew" there.
An estimate of the national economic damage resulting from air
pollution is about 7.5 billion dollars annually. 1 Included are injuries
to vegetation and livestock, corrosion and soiling of materials and
structures, depression of property value, etc. With such a large
economic loss nationally from air pollution, each community should be
interested in assessing local damage.
A study undertaken here included an attempt to evaluate the effect
of local air pollution on two materials: white lead-base house paint
and silver plate.
The white lead-base paint is sensitive to hydrogen sulfide
under certain conditions, and some communities have reported whole
houses blackened from H2S episodes. The silver plate approximates
silverware. As any housewife knows, during some seasons, constant
polishing is needed to keep silverware bright, whereas at other times
silverware tarnishes very slowly. Silver plate is sensitive to com-
pounds of sulfur including H2S and is a much more sensitive indicator
of these compounds than is lead-base paint.
SILVER TARNISHING
The clean surface of metal is rapidly oxidized when exposed to
air. The initial reaction is rapid, but oxidation decreases as a pro-
tective film of oxide is formed. At first, this film, at ordinary tem-
peratures, is normally invisible. Prolonged oxidation or an increase
in temperature may result in films that produce interference colors.
High temperatures and prolonged oxidation produces thick surface
layers of oxide or scale. 2
If substances other than oxygen are present, the surface film may
be composed of a mixture of oxides and other reaction products.
Normally, there is some sulfur in industrial atmospheres, which
results in metal tarnish films composed of oxides plus sulfides. Silver
forms sulfide and sulfate in preference to oxide if any sulfur compound,
either organic or inorganic, is present. 2 The sulfide film of silver,
unlike the oxide, forms a visible tarnish even at room temperatures. 3
108 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
The rate of reaction of metals with gases to form corrosion coatings
depends on the relative permeability of the coating to the reactants. A
porous corrosion film is less protective than a nonporous film that
adheres tightly to the metal surface. 4 An example of the latter is the
oxide film that forms on aluminum and prevents further oxidation. The
formation of tarnish on silver seems to be an electrochemical pheno-
menon 2 in which metal ions diffuse through the surface film to react
with the sulfur compounds. There is some movement of reactant ions
toward the metal surface, but the metal ions diffuse much faster. The
silver sulfide film formed on the surface of the silver does not halt
further reaction, as does the oxide film of aluminum, but lowers the
rate of reaction.
As a result of the electrochemical nature of silver tarnishing, the
formation of the surface film follows the parabolic-growth law. 5
According to this description, the silver sulfide film forms rapidly
when the silver surface is clean and untarnished. As the reaction pro-
ceeds, a layer of tarnish is formed, and the reaction rate decreases in
a semiexponential function. The following graph shows the general form
of the curve where t represents film thickness. 3
time
The film continues to form for a long time, but at a decreasing
rate.
Various methods of detecting And measuring films on metal sur-
faces are reported in the literature; these include galvanometric,
electrical, and optical. 2 The method of measurement used in this study
was based on light reflectance. In essence, the method consists of
measuring the decrease of reflectance of a silver plate as the tarnish
film builds up. The instrument used consisted of a galvanometer and a
light unit that directed a beam of light on the silver blank at an angle of
60 degrees to the normal. The specular beam was registered by a
photocell and the resulting current measured by the galvanometer unit.
Initial measurements were made on all unexposed silver plates and
periodic measurements were made thereafter during the exposure
period.
On the basis of decrease in reflectance, a comparison was made of
different exposure sites throughout the area. Silver plates were exposed
at the Moscow, Idaho, "control" station to provide information on
Effects of Air Pollution - Chapter V 109
-------
tarnishing in a nonindustrial community. It is believed that the results
of the tarnishing measurements are a fair indication of relative pollution
by sulfur compounds. The results are not quantitative, but comparisons
can be made between one station and another with reference to the
"control" station.
Procedure
Silver blanks were made from 3- by 3- by 1/8-inch brass plates
coated with copper and then with silver by electrodeposition. The
silver, 1/2 mill thick, was buffed to remove tarnish and oil films, and
then the plates were wrapped in sulfide-free paper to prevent formation
of tarnish before exposure. The instrument used for the reflectance
measurements was a Photovolt-Photoelectric Reflection Meter Model
610. A reference of known reflectivity was used to standardize the
instrument.
Reflectance readings were made on all samples prior to placement.
On each blank, reflectance readings were taken at six areas; the results
were averaged.
It was found necessary to place new samples in the field every
month because of the reduction hi reactivity with thickening tarnish
film, as predicted by the parabolic-reaction equation. The "old"
samples were left exposed for the remainder of the study. Thus, the
first sample at each station would remain at the field for 6 months,
whereas the second would remain only 5 months, etc. Reflectance
readings were made on all samples at each station at least once
every 2 weeks. (Table 5-1.)
Results
In evaluation and interpretation of the results of the silver-tarnish-
ing measurements, several previously mentioned factors must be con-
sidered. The silver surface becomes less reactive as the tarnish film
builds up and becomes almost unreactive after a time. Normally the
samples suffered a rapid decrease in reflectivity for the first 30 days
and a lesser decrease the next 90 days. Thereafter, reflectivity did
not change significantly, as is shown by Figure 5-1, which presents the
results obtained from the first samples and indicates the decrease in
reflectivity with time.
Reproducibility of results is another important consideration. 2
Great care must be observed in preparing and exposing samples and
in measuring reflectivity, and even then, absolute reproducibility is
not obtainable. Factors that affect the reproducibility of the results
may be divided into two categories, namely, those that involve the
environment and those that involve the metal surface. The metal sur-
face is affected by dirt, surface films, oil films, stresses introduced by
polishing, 3 and a variety of other factors. The surface film may
appear as a smear or even a "thumbograph" 3 when the metal surface
is not completely clean. From photographs, it can be observed that a
smearing of the tarnish film did occur (Figure 5-2).
110 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
100
90
80,
~1 1 1 1 1 1
0 MOSCOW
....^ LEWISTON ORCHARDS
,0 LEWISTON RESIDENTIAL
LEWISTON COMMERCIAL
WEST CLARKSTON
&—"& CLARKSTON COMMERCIAL
J L
10 20 30 40 50 60
70 80 90 100 110
DAYS OF EXPOSURE
120 130 140 ISO ISO 170 ISO
Figure 5-1. Rate of tarnishing of silver samples
for 6-month study period.
One other factor contributing to the observed smearing effect is the
variation in reactivity across the silver surface itself. When a metal
surface is machined or abraded, stresses are induced in the metal both
from mechanical action and from the heating that results. 2 Since the
silver samples were buffed with a polishing compound, some residual
surface stress might be expected to remain in the metal. Annealing
under an inert atmosphere would remove the surface stresses, but this
was not done. The effect of the uneven stress distribution in the sur-
face of the sample promotes reaction on the lines of stress, whereas
reaction on the unstressed portions of the sample occurs at the normal
rate. The faster reaction at lines of stress, together with the effect of
surface films of oil or oxide mentioned previously, results in the
mottled appearance of some of the samples.
Smearing or mottling of the surface film hinders an accurate
measurement of the tarnishing rate. The areas that are relatively un-
tarnished remain highly reflective whereas the heavily tarnished areas
are much less reflective. The net effect is to introduce into the read-
ings a variability that reduces the reproducibility of the results. The
smearing does not obviate drawing of conclusions from the tests, but
some variability in the results must be allowed for.
The environmental factors that affect the reproducibility of results
are humidity, temperature, and homogeneity of the atmosphere. The
effect of humidity on the tarnishing of silver is not particularly signifi-
cant. 2J5 Some atmospheric water must be present for tarnishing to
Effects of Air Pollution - Chapter V
111
-------
Table 5-1. RATE OF SILVER TARNISHING BY AREA DURING STUDY PERIOD
Date of
reading
Sample
number
November
3
4
7
8
13
16
21
29
December
6
20
21
22
January
10
11
22
23
Cumulative decrease in reflectance, %
1
Moscow
1
70a
0
0
0
2
70
0
0
0
18
7i
24
30
36
2
Lewiston
Orchards
4
75
0
0
3
13
18
19
20
10
76
9
17
18
15
72
2
21
26
35
3
Lewiston
residential
3
76_
2
15
28
32
34
51
53
6
76
25
44
45
16
63
7
20
27
34
37
4
Lewiston
commercial
9
82
8
24
34
32
44
50
55
7
78
6
13
21
17
70
19
25
33
38
5
West
Clarkston
5
73
1
1
5
11
12
25
14
71
5
23
29
32
6
Clarkston
commercial
8
80
2
4
14
23
23
60
11
78
31
60
13
69
14
22
28
31
-------
Table 5-1. RATE OF SILVER TARNISHING BY AREA DURING STUDY PERIOD (Continued)
Date of
reading
Sample
number
February
1
22
19
21
22
March
1
30
April
1
2
4
15
16
28
29
Final re-
Cumulative decrease In reflectance, %
1
Moscow
1
5
5
5
5
flectance, %65
2
0
0
0
0
70
18
0
0
0
0
70
24
83
0
1
5
20
65
30
75
0
0
10
65
36
80
20
60
2
Lewiston
Orchards
4
25
30
30
45
10
20
30
45
15
16
30
30
40
21
78
14
33
40
40
26
74
13
17
50
35
79
10
65
3
Lewiston
residential
3
60
60
15
6
55
55
55
55
25
16
45
45
45
45
20
20
80
48
65
65
65
15
27
79
40
60
60
20
34
70
30
40
30
37
75
26
45
30
4
Lewiston
commercial
9
60
60
60
60
20
7
30
30
30
30
50
17
20
35
30
35
35
19
81
65
65
65
65
15
25
78
60
60
60
20
33
78
55
55
25
38
67
45
45
20
5
West
Clarkston
5
60
60
60
60
10
14
60
60
60
60
10
23
77
61
65
65
65
10
29
73
9
16
25
50
32
81
22
35
50
6
Clarkston
commercial
8
60
60
60
60
20
11
60
60
60
60
20
13
50
50
50
50
20
22
76
55
55
55
55
20
28
75
22
49
55
20
31
75
17
40
35
a Underlined number shows reflectance reading for each sample before exposure.
-------
•d
O
r
r
i
CO
O
o
STATION NO. 2. LEWISTON ORCHARDS
STATION NO. 3, LEWISTON RESIDENTIAL
STATION NO. 4, LEWISTON COMMERCIAL
STATION NO. 5, WEST CLARKSTON
STATION NO. 6, CLARKSTON COMMERCIAL
Figure 5-2. Photographs of tarnished silver samples.
-------
occur, but normal conditions supply more than enough. Silver is unlike
many other metals in that there is no critical humidity below which its
tarnishing ceases. 2,6 The ambient temperature over the ranges en-
countered in this study would have little detectable effect on the tarnish-
ing rate. 2
Consideration of the effect of rapidly changing atmospheric concen-
trations of sulfides on the silver samples cannot be neglected. After
exposure to several "slugs" of tarnish-producing gases, a sample may
be so tarnished that it is somewhat desensitized to smaller concentra-
tions of gas. In some particularly bad periods during the study, samples
suffered a 50 percent decrease in reflectivity after less than 2 weeks of
exposure. Ideally the samples should be constantly monitored and re-
placed when their reflectivity falls below an optimum level. In this
study, equipment was not available for continuous monitoring. The
readings represent an average decrease over the time between the
readings rather than the day-to-day variation.
Figure 5-1 presents the changes of reflectance as a function of ex-
posure time for the six original samples, which remained in the field for
the duration of the study, a total of 150 days each for five samples and
175 days for one.
The slope of a curve indicates the tarnishing rate over any particu-
lar time period. As expected, the samples tarnish rapidly the first
month and then become slightly resistant to further tarnishing. Several
exceptions to the expected behavior may be observed. The Moscow
sample showed almost no tarnishing over the study period, suffering a
gradual decrease of reflectivity of no more than 5 percent. This small
decrease is attributable to dust and variation in the measurement tech-
nique. Since this nonindustrial community was our "control" station,
no tarnishing was expected and almost none was found. Both original
samples in Clarkston and one in Lewiston show a rapid decrease in
reflectivity for 30 days with a break in the curve, a leveling off, and
then after 2 weeks another decrease of reflectivity. The exact cause
of the leveling off of the tarnishing curve and the subsequent increase
in tarnishing rate is not known. Two factors are important, the surface
effects on the metal sample and the changes of atmospheric concentra-
tion of sulfide gases. As the tarnish film thickens, the metal surface
becomes less reactive to small concentrations of sulfide gases. E^S
measurements for the first few weeks of December show relatively
little pollution. This fact, plus the decreased reactivity of the metal
surface, seems to account for breaks observed in the tarnishing curves.
The final level of tarnishing reached by each sample indicates the
sulfide pollution in the area. The curves group themselves into three
levels: Moscow, Lewiston Orchards, and the Lewiston-Clarkston area.
This is what would be expected, since Moscow has little sulfide pollu-
tion, whereas Lewiston Orchards is high enough above the valley to
escape most of the pollution.
Effects of Air Pollution - Chapter V 115
-------
Tarnishing in each area is shown by month in Figure 5-3. The data
•were taken from the first 30 days of exposure of each of the samples,
which were exposed at roughly 30-day intervals. During the first few
weeks of exposure, the samples were very reactive, and so it is believed
that the first 30 days represents a more accurate measurement of
pollution.
The lowest average tarnishing, for all stations except Moscow, was
noted in January and December. H2S measurements show relatively
little pollution in December and January, which agrees with the silver-
tarnishing measurements.
Conclusions Regarding Silver Tarnishing
Several important conclusions may be drawn from Figures 5-1
through 5-3. First, the tarnishing rate of silver plate is greater in the
Lewiston-Clarkston area than in Moscow and Lewiston Orchards. As
shown in Figure 5-4, the decrease in reflectivity in the Lewiston com-
mercial area is the greatest (an average of 41% for the 6 months); the
decrease is least for Moscow (4%). During individual months, the
difference in tarnishing rate was sometimes larger, with a maximum
difference in February when reflectivity of the Lewiston commercial
sample decreased by 68 percent. During the same months reflectivity
of the Moscow sample did not decrease at all.
Since decrease of reflectance of silver roughly indicates the pre-
sence of sulfide gases, it can be concluded that the atmosphere in the
Lewiston-Clarkston area has a much greater concentration of these
gases than does that in Lewiston Orchards and Moscow. The high tar-
nishing rate in Lewiston seems to indicate that this city is closer to the
source of sulfide gases than is Clarkston. Proximity to a source, as
*- f U
c
u
1 60
-
t/J 50
LLI
g 40
LU
Q
LU 30
u
z:
< 20
u
REFLE
o o
• MOSCOW
D LEWISTON ORCHARDS
~ E2 LEWISTON RESIDENTIAL
d LEWISTON COMMERCIAL
— OH CLARKSTON RESIDENTIAL
^ CLARKSTON COMMERCIAL
-
—
_
F
[77
X-
y
•y,
/,
\
Tn
[:-:-
p
F
/,
//
y/
!
ii
-
;-;-
~-
rl;
F
X
RH
1
:-:•
f
y-
%
•'/,
//
'/
—
-_-_
L-:
r7^
I
/'
—
~
P
p:
^
y^
v;
'/•
y\.
'y^
-
-
r~-
:-:
::::
—
_
14 45 57 33 39
APRIL
Figure 5-3, Monthly tarnishing of silver samples by station.
116
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
ii
» 40
g
H
U
< 0
LEWISTON LEWISTON CLARKSTON WEST LEWISTON
COMMERCIAL RESIDENTIAL COMMERCIAL CLARKSTON ORCHARDS
Figure 5-4. Average silver tarnishing by station for
6-month study period.
well as a downwind location, would lead to a high tarnishing rate, as is
the case in Lewiston. The pulp mill is the only major source of sulfide
gases in the Lewiston-Clarkston area (see the emission inventory,
Chapter m), which leads to the conclusion that its emission are the
cause of the rapid tarnishing observed. Silver tarnishing indicates a
condition that might also produce accelerated corrosion in a variety of
other materials, notably iron and steel.
PAINT BLACKENING
In areas of industrial activity paint blackening is not uncommon. '
In communities throughout the United States, exterior house paint is
blackened, sometimes in whole areas during a particularly bad episode.
The type of paint that is normally discolored contains white lead or
some other lead compound. The lead reacts to certain gases in the air,
notably H2S and under proper conditions, forms a black compound, lead
sulfide.
Two factors contribute to paint blackening. First is the fact that
many painters and houseowners believe that lead pigments are nec-
essary to make a good paint. Second is the presence of H^S in the air.
The development of new paints, which do not use lead compounds as
pigments, has alleviated the problem for most areas. The possibility
of using lead-base paint as an indicator for H2S was of interest,
however, so paint studies were made.
Kffects of Air Pollution - Chapter V
117
-------
The formation of lead sulfide in lead-base paints depends on several
factors in addition to the presence of H2S in the air. An investigation by
the Pittsburgh Club of the Federation of Paint and Varnish Production
Clubs 8 resulted in the following conclusions:
1. With H2S in the atmosphere, no blackening occurs unless the
paint contains lead pigments.
2. The type of white-lead pigment in the paint is immaterial.
The degree of blackening varies directly with lead metal
content.
3. Practically no blackening occurs unless the paint film is
actually wet with water, regardless of humidity.
4. The concentration of H2S in the atmosphere appears not to
be critical. Small concentrations produce blackening under
optimum conditions at slower rates than large concentrations.
5. H2S blackening is considerably delayed if the paint film is
glossy and unweathered. Paint formulations high in polyvinyl-
chloride, therefore, darken more readily since less protective
vehicle is present.
Procedure
Dutch Boy white lead-base paint (95% white lead in a linseed oil
vehicle) was applied to 3- by 3- by 1/4-inch stainless steel coupons
with a laboratory coating rod that produced a thin film of paint. After
the first coat had set, the coupon was coated on the other side. The
paint was allowed to dry for 2 days before reflectance readings were
taken.
Reflectance measurements were made with the same basic unit used
for silver reflectance. The search unit uses a light beam normal (per-
pendicular) to the paint surface and a circular photocell to measure the
light reflected from the paint surface at an angle of 45 degrees.
A reference paint sample was used to standardize the instrument,
and the reflectance of each sample was determined at several points on
the panel (there was some variation in the paint thickness). The average
reflectance reading was recorded for each panel.
The samples were exposed in the following manner: Eight paint
panels were attached to the exterior walls of each of six sampling
stations, so that two panels faced north, two south, two west, and two
east. One panel on each wall was placed in a protected position, e.g.,
under the eaves of the roof, where rain would not wet it. The other
panel was placed in a position exposed to sun, wind, and rain.
118 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
Results
The results obtained from the paint samples were inconclusive. The
samples in the exposed mountings suffered greater decrease in reflect-
ance than did the corresponding protected sample in 13 cases. Conversely,
the protected samples suffered a higher decrease of reflectance in 11
cases (Table 5-2). There was no observable damage from H2S; therefore,
the loss of reflectivity may be attributed to weathering and soiling.
Results of chemical analysis of several paint samples show that
no lead sulfide was detectable in the paint. This adds credence to the
conclusion that H2S damage did not cause reflectivity loss.
H2S was detected in the area by analysis of air samples, silver
tarnishing, and AISI sampler tapes. The failure of the paint to respond
to the H2S may be attributed to two factors. First, the paint used in the
study had a high gloss that would make it resistant to sulfide damage.
The assumption that sufficient weathering would take place over the
study period to make the paint reactive was not valid. Examination
of the samples at the end of the study revealed that the surface was
still glossy, and apparently little weathering had occurred. Second,
the samples were exposed "dry" and this retarded the formation of
lead sulfide, as has been shown in experiments. 8 Admittedly, fog
and dew may contribute to the formation of a water film on the paint
surface, but to what extent is unknown.
Conclusions Regarding Paint Blackening
The results of the paint study may be regarded as inconclusive. It
would seem that future studies might profit from this experience. Some
method of keeping the paint covered by a film of water must be devised.
The blanks should be weathered artificially or in an area free of H2S to
overcome the glossiness of the paint surface. A long-term comparison
of "leaded" versus "nonleaded" paints should be made.
HEALTH AND WELFARE IMPLICATIONS
Adverse effects from ambient atmospheres polluted with mixtures
of various substances have been well documented, but unfortunately,
many specific industrial sources of pollutants, including the pulp and
paper industry, have not been adequately studied. Such information is
only now being collected and reported. Preliminary data from a recent
health survey of a community whose air was contaminated by stack dis-
charges from a pulp and paper mill seemed to indicate that the pol-
lutants may have been associated with nonspecific respiratory tract
irritation.
Our lack of more precise data does not, however, leave us devoid
of any data from which we can deduce some reasonable and useful con-
clusions. We know the effects upon health and well-being of some of
Effects of Air Pollution - Chapter V 119
-------
Table 5-2. RATE OF PAINT DARKENING BY
AREA FOR STUDY PERIOD
Sampling
station
Moscow control 1
Lewiston Orchards 2
Lewiston residential 3
Lewiston commercial 4
West Clarkston 5
Clarkston commercial 6
Clarkston commercial 6S
titanium dioxide paint
Direction
of exposure
North
South
East
West
Average
North
South
East
West
Average
North
South
East
West
Average
North
South
East
West
Average
North
South
East
West
Average
North
South
East
West
Average
North
South
East
West
Average
Decrease in reflectance, %
Exposed
mounting
13
16
3
18
13
7
7
3
7
6
9
9
7
0
6
10
14
23
11
15
6
11
4
7
7
8
8
7
7
8
5
7
5
5
6
Unexposed
mounting
14
23
16
3
14
3
6
5
4
5
0
7
6
6
5
3
2
13
7
6
9
7
7
10
8
11
16
13
4
11
120
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
the individual noxious materials discharged into the air from pulp and
paper plants. Presented here are the effects of hydrogen sulfide (and
the organic sulfides) and nonspecific carbonaceous material contained in
black smoke. 9-13
The sulfides of hydrogen (and the organic sulfides) have a rather
offensive odor, even in very small concentrations. At greater concentra-
tions - unlikely in the ambient air from industrial processes - the sul-
fides irritate exposed membraneous surfaces, causing excessive tearing
and dry cough. The concentrations one may expect in the air generally
cause a nuisance by virtue of their disagreeable odors, which can lead
to nausea and vomiting.
The carbonaceous material contained in black smoke can be expect-
ed to act primarily as an irritant, causing sneezes and coughs. Nothing
more definite is known about the smoke, since its exact chemical com-
position is so variable.
Before this study began, it was decided that an investigation should
be made of the potential (and, possibly, actual) health effects locally.
For this purpose, a preliminary evaluation was made by an experienced
air pollution physician who obtained information through interviews with
a large segment of the local practicing physicians. Despite the diffi-
culties and uncertainties in this type of "data" collection, it was believed
that the following summarizing statements could reasonably be made:
1. Fifty percent of the physicians practicing in Lewiston and
Clarkston were interviewed. Several had been practicing
for more than 10 years in the area. A large majority of
the physicians stated that they concurred in their patients'
belief that certain of their disease conditions were related
to air pollution.
2. Three of the 17 physicians interviewed believed that the air
pollution problem was more of a nuisance than a health prob-
lem. The remainder attributed to air pollution varying
degrees of effects ranging from aggravation of existing con-
ditions to causation of specific illnesses.
3. Several physicians noted improvement in patients with
respiratory conditions when the patients moved from the
area of high pollution or used other means of reducing
pollution exposure (air conditioning).
This information, although subjective in nature, is based on obser-
vations by experienced local physicians. Although it provides no specific
evaluation of the extent or nature of the effects on health in the com-
munities, it is consistent with information developed by objective means
elsewhere.
Effects of Air Pollution - Chapter V 121
-------
On the basis of this information it is not possible to conclude that
serious health effects in this area can be associated with the air pollution
levels noted in this report. With the background of expert opinion of
physicians in the area and with information from other studies, however,
it can be concluded that, to avoid the possibility of adverse health effects,
levels of contamination of sulfides and smoke must be reduced.
Nuisances may adversely affect human well-being. Although ex1-
tremely difficult to quantify and assess objectively, there should be a
wide community concern, since they are inimical to the general com-
munity welfare. In so highly subjective an area, it is not possible to
provide clear guidelines on which to base reduction of air pollutants
that lead to such nuisances, but as in the problem of ensuring adequate
health protection, the reduction of contamination to levels below those
that cause reduced visibility, soiling, other materials damage, irritation,
and offensive odors would substantially reduce the likelihood of diffi-
culty.
In conclusion, it is probably safe to assume that reduction of pol-
lutants to levels below those that may result in nuisance effects would
provide a reasonable margin of safety for human health.
SUMMARY
Silver plates exposed to the atmosphere in the control station at
Moscow showed little tarnishing. In the valley locations, silver plates
suffered greater tarnishing than those in the upland sites. Tarnishing
of new plates was greatest during the first 30 days of exposure. During
December and January lower levels of tarnishing corresponded to
lower levels of pollution. Tarnishing, as an indicator of sulfide gases
in the air, was greater in Lewiston than in Clarkston.
Data obtained from exposed paint panels were inconclusive. This
was attributed to the durability of the glossy paint employed and to the
lack of a film of moisture on the exposed surface.
Studies to provide precise data relating to health effects and pol-
lutant concentrations were not made. Information obtained through
interviews of local physicians revealed that many believed local air
pollution was adversely affecting some of the townspeople.
REFERENCES
1. Mackenzie, V.G. Air pollution needs action now. Speech presented
to Inter-County Committee of the Detroit Metropolitan Area March
1961.
122 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
2. Uhlig, H.H. The Corrosion Handbook. J. Wiley and Sons, Inc., New
York, N.Y. 1948.
3. Evans, U.R. The Corrosion and Oxidation of Metals; Scientific
Principles and Practical Applications. E. Arnold, London. 1960.
4. Pilling, N.B., and Bedworth, R.E. Paper on oxidation of metals at
high temperature. Institute of Metals, 29:529. 1923.
5. Hoar, T.P., and Price, L.E. The electrochemical interpretation of
Wagner's theory of tarnishing reactions. Transactions of the Faraday
Society, 34:867. 1933.
6. Burn, R.M., and Bradley, W.W. Protective Coatings for Metals, 2nd.
ed. Reinhold Publishing Corp. 1955.
7. Greathouse, G.A., and Wessel, C.J. Deterioration of Materials,
Causes and Preventive Techniques. Reinhold Publishing Corp., New
York, N.Y. 1954.
8. Ward, G.B. Blackening effects of hydrogen sulfide on exterior white
house paints. Federation of Paint and Varnish Production Clubs,
Official Digest, 2:1089. November 1956.
9. Stern, A.C., ed. Air Pollution. Vol. I, Chap. 10, Goldsmith, J.R.
Effects of Air Pollution on Humans. Academic Press, New York.
1962.
10. Stern, A.C., ed. Air Pollution. Vol. II, Chap. 37, Stern, A.C. Air
Pollution Standards. Academic Press, New York, 1962.
11. Patty, F.A., ed. Industrial Hygiene and Toxicology. Vol. II, Toxi-
cology, Chap. XXIV. Interscience, New York. 1962.
12. World Health Organization. Air Pollution. Heimann, H. Effects of
Air Pollution on Human Health. Columbia Univ. Press, New York.
1961.
13. Sax, N.I. Dangerous Properties of Industrial Materials. Fourth
Printing, Reinhold Pub. Corp., New York. 1961.
Effects of Air Pollution - Chapter V 123
-------
CHAPTER VI. PUBLIC AWARENESS AND
CONCERN WITH AIR POLLUTION *
INTRODUCTION
In its report, "National Goals in Air Pollution Research," the Surgeon
General's Task Group states: "The aspects of air pollution which are
most apparent and of greatest personal concern to the individual probably
are irritation to the eyes, nose, and throat, malodors, and the reduction
of visibility. The pollutants responsible for these effects are undesirable
whether or not they cause long-range health effects or economic losses,
because they constitute an annoyance to people."
Since aerometric study by itself cannot disclose the extent of this
annoyance to people, a survey of public awareness of and concern with
air pollution was conducted in Clarkston.
Included in this survey were approximately 100 randomly selected
heads of Clarkston households or their spouses - persons who bear the
major share of responsibility for making and maintaining a residence in
the community. Specially trained interviewers, using a questionnaire
developed for this study, visited each member of the sample in his or her
home between May 20 and 25, 1962, to gather data. To avoid premature
focus on air pollution, interviewers defined the survey situation as one
concerned with "certain health conditions in Clarkston."
Survey results disclose, first, that 81 of the 104 respondents believe
a condition of air pollution does exist "at some time during the year" in
Clarkston. Furthermore, in reply to the question, "What do you think the
words air pollution mean to most people in the area?" 91 percent of the
104 respondents indicated they thought it was some form of malodor; 74
percent, low visibility; 62 percent, frequent nose or throat irritation; and
40 percent, frequent eye irritation. In contrast, only 27 percent thought
that air pollution meant too much dust and dirt in the air.
Against this background of widespread public awareness of the exist-
ence of air pollution, the survey considered next the degrees to which
atmospheric pollution gave rise to feelings of annoyance or concern.
Spontaneous expressions of annoyance furnish one type of evidence of
this concern. Interviewers asked at the start of their visit, "Are there
some things you don't like about living in Clarkston? If so, what?"
About 33 percent (34) of the respondents listed spontaneously a disadvantage
explicitly related to air pollution. Of these, 23 respondents referred to
malodors (e.g., "smells," "bad smells," "stinks"); 4, low visibility (e.g.,
"haze," "smog," "smoke"); 5 some unspecified aspect of air pollution
(e.g., "bad" or "poor" air); and 2 listed multiple aspects of air pollution.
* See complete report, PUBLIC AWARENESS AND CONCERN WITH Al R POLLUTION-
CLARKSTON, WASHINGTON - MAY 1962. To be published by the Division of Air
Pollution, Public Health Service.
124 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
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A second index of concern or annoyance with air pollution appears in
the fact that about 66 percent of the sample said they were bothered
"somewhat" or "quite a lot" by air pollution over the city — a percentage
identical to that found among Los Angeles residents in 1956.
A third indication of concern or annoyance is that 7 out of every 10
respondents (70 percent) called air pollution a "serious" or "somewhat
serious" problem for their community. By contrast, in the spring of
1962, only 45 percent of Buffalo residents rated air pollution a "serious"
problem for their city in answer to a similar survey question.
As indicators of the trend of public annoyance or concern with air
pollution in Clarkston, the survey found that about 66 percent of those
who regarded air pollution as a "serious" or "somewhat serious" com-
munity problem said that it either had been so continuously or was be-
coming a more serious problem each year.
SOURCES OF AIR POLLUTION
Although Clarkston residents differ in the degree to which they ex-
press annoyance or concern with air pollution, the survey revealed
that they show virtual unanimity in defining as its prime source the kraft
paper mill. Three lines of evidence support this conclusion.
First, of the respondents who spontaneously mentioned air pollution
as a Clarkston disadvantage and who specified a source, all mentioned
"the mill" and only the mill as point of origin. A typical response to the
question, "Are there some things you don't like about living in Clarkston?"
was: "The smell of the pulp mill."
Second, 26 of 33 respondents who had been living in Clarkston since
1950 or before and who said air pollution existed in Clarkston at present
answered the question "When did you first notice air pollution in Clarks-
ton?" by saying "When the mill started." Four gave a date between 1951
and the present; only two gave a date in 1950 or before; one said he did
not remember.
Third, in answer to the question, "What do you think are the major
sources of air pollution in this area?" (Item 15 in the questionnaire
form), 92 percent (75 respondents) of the respondents who showed
awareness of air pollution named "the mill" first. Two persons said
"automotive vehicles," one person, "the dump," and one person, "the
stockyard."
ACTION TO REDUCE AIR POLLUTION IN CLARKSTON
From the foregoing sections emerges the outline of a problem
situation disturbing in some degree to 7 out of 10 Clarkston residents
Public Awareness and Concern - Chapter VI 125
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in the survey, namely, the problem of air pollution conceived as mal-
odor, a problem attributed almost universally by those residents to the
kraft paper mill. To explore the potential for action to ameliorate the
air pollution among Clarkston residents, the survey attempted first to
discover the extent to which they believed the problem could be alleviated.
For this reason interviewers asked (Item 14): "Do you believe that air
pollution in Clarkston . . .
1. Cannot be reduced below its present level,
2. Can be reduced below its present level,
3. Can be almost completely eliminated?"
Replies to this item show that only 4 percent of the subjects who
believed air pollution existed in Clarkston (81 replies) took the position
that it could not be further reduced, whereas 14 percent said they did
not know. By contrast, 58 percent believed air pollution could be re-
duced below its present level, and 21 percent believed it could be almost
completely eliminated in Clarkston.
Next, interviewers asked respondents, "Which one of these state-
ments do you think best describes the effort (each of the pollution
sources respondent mentioned) is making to control air pollution in this
area?" With only figures for the kraft paper mill considered, nearly 75
percent of those who listed it as a pollution source said to varying de-
grees that "it was not doing as much as it should" to control air pollution
in Clarkston.
These two sets of data lead to the inference that a relatively high
potential for situation-altering actions exists in Clarkston with ref-
erence to the air pollution problem. Eighty percent of respondents who
recognize the existence of the problem say it can be ameliorated; 75
percent of those who consider the pulp mill as principal source of the
problem say it is not doing as much as it should towards this amelioration.
CONCERN WITH AIR POLLUTION IN RELATION TO DEMOGRAPHIC
AND SOCIAL CHARACTERISTICS OF CLARKSTON RESIDENTS
Previous studies have documented an ecological component — area
of residence — in levels of exposure to different types of ambient air
pollution, and by extension, to degrees of concern with air pollution as
a personal and community problem. A north-south division seemed
likely to provide some differences in residential exposure to and concern
with pollutants in Clarkston. Sycamore Street, extended to 15th, was
used as boundary between the northern and southern halves of the city.
The first and major finding, from responses of sample participants
in these two sectors, is that they show no difference in recognition of
the existence of air pollution or concern with it as a problem. A
specially devised composite scale was used for indications of concern.
On the other hand, other factors show marked relationship to the degree
126 Am POLLUTION IN LEWISTON-CLARKSTON AREA
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of concern with air pollution manifested; these are occupation of house-
hold head and length of residence in the community. Approximately 66
percent of persons interviewed who had been living in Clarkston since 1950 or
before were "highly concerned" with air pollution as a problem, com-
pared to a little over 33 percent of those who had moved to the city in
1951 or later. Independent of length of residence, respondents from
households whose heads are professionals, proprietors, or managers
expressed the most concern with air pollution; those from households
whose heads are semiskilled or unskilled workers expressed the least
concern; and those from clerical and skilled-craft occupational back-
grounds expressed concern in the middle range. These findings may
be interpreted to mean that increasing length of exposure to what is
defined as noxious environmental conditions produces increasing ex-
acerbation rather than habituation to it. They also indicate that air
pollution in Clarkston constitutes a community-wide problem. From a
sociological point of view, the survey finds that the more persons are
involved or identified with the community, the more they tend to be con-
cerned with air pollution as a community problem. In other words,
concern with air pollution in Clarkston apparently does not stem from,
lead to, or express itself with generalized negative feelings or rejection
of the community as a place to live; on the contrary, such concern
appears to grow out of widespread feelings of civic pride, which results
in a desire to ameliorate the situation. Of respondents 85 percent rate
Clarkston an excellent or good place to live despite the fact that 70
percent said that air pollution was a "serious" or "somewhat serious"
problem for their community.
From the methodological standpoint of research on enviornmental
health problems, this study may be of interest in that it took place under
circumstances that dramatize the independence of psychosocial vari-
ables, awareness of environmental pollution, and definition of such
pollution as an individual or social problem from physically defined
levels of pollution. The physical level of air pollution in Clarkston
appears to be roughly constant for people according to area of resi-
dence, and yet, phenomenal awareness of and concern with air pol-
lution as a problem vary markedly among socially defined subgroups.
Awareness or definition of pollution as a problem, in a society,
cannot, therefore, be regarded as a simple direct function of the
society's capacity to produce pollution. Indeed, some of the same
social factors that induce high capacity to pollute the air may lead to
low awareness of air pollution as a social problem.
Conversely, a situation is entirely conceivable in which an in-
creasing concern with air pollution as a social problem may be
manifest in the very same place where and in the very same period
when physical levels of pollution are decreasing. In fact, this may
well be the situation in Clarkston. No grounds are known for doubting
the statements of officials of the kraft mill that they have taken
measures to reduce substantially the quantity of odor-bearing effluent
from the mill in the period 1951 to May 1962; yet in May 1962, 52
Public Awareness and Concern - Chapter VI 127
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percent of respondents to the present survey said air pollution as mal-
odor had either remained unchanged over these years as a serious
problem for Clarkston or had increased in gravity.
Examples of this kind illustrate the need for a broad research
attack on the relationship between the social- and physical-system
dynamics of man in community. "If men define situations as real they
will be real in their consequences." The reality of the Clarkston
residents' definition of their air environment is evidently no simple
function of the reality of that environment as defined aerometrically.
From increased understanding of the independence and inter dependence
of these two orders of reality may come progress in achieving the goals
of environmental health.
SUMMARY
The survey of public opinion concerning air pollution showed that
approximately 80 percent of the persons interviewed believed that
Clarkston had an air pollution problem. About 66 percent indicated they
were bothered by it. Bad smells, frequent haze or smog, nose and
throat irritation, eye irritation, and excessive dust and dirt were cited
as the principal air pollution phenomena. More than 90 percent (75) of
the respondents who reported they were aware of air pollution named the
pulp mill as responsible. More than 33 percent believed official enact-
ment of air pollution control measures is needed. Air pollution in Clarks-
ton appears to constitute a community-wide problem. Concern appears
to be associated with civic pride and a desire to ameliorate the situation.
Documentation of these data is set forth in the complete report.
CHAPTER VII. APPRAISAL AND SOLUTION
GENERAL
Data and information obtained during this 6-month study indicate
that the cities of Lewiston and Clarkston have air pollution problems of
sufficient magnitude to warrant immediate initiation of a program of
action to improve and conserve air quality. Orderly community
development requires a program of air resources management equal,
at least in the interest and effort applied, to the planning programs for
utilization and control of land and water resources.
The ability of the atmosphere in the Lewiston-Clarkston valley to
cleanse itself has been exceeded on many occasions during periods of
atmospheric stagnation characterized by unusually low wind speeds and
128 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
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persistent atmospheric temperature inversions. The result has been an
accumulation and concentration of pollutants in quantities sufficient to
affect the welfare of residents of the area adversely.
Prior to this study, complaints about bad odors and visibility
reduction had indicated a growing public consensus that something was
wrong with the air in Lewiston-Clarkston and that something had to be
done to correct the situation. Episodes of damage to house paint
coupled with rapid tarnishing of silver had reinforced the opinion that
conditions were deteriorating.
Health effects were not investigated in detail. Sufficient informa-
tion was obtained, however, to indicate a certain degree of apprehension
about harmful effects of air pollution. Specifically, some of the physicians
in the area have pointed out a need for medical studies of the effects of
air pollution on health of residents of the communities. Medical
studies of susceptible persons would provide sufficient information to
judge whether or not an actual health problem existed. The extent and
severity of any actual problem would necessarily be part of this health
study.
The need for air pollution control by the communities and their
industries is implicit in the apprehension apparent in the pressures
exercised by the afflicted citizenry who motivated the request for assist-
ance from the Mayor of Clarkston to the Public Health Service. This
concern is also revealed in the public opinion survey. Public concern
and awareness are important measures of an air pollution problem,
since they reflect the importance the public attaches to it. 1 In the
minds of the people of this area, an air pollution problem does exist.
The events leading to this study are a part of the public's desire for
improved utilization and management of the air resources of the com-
munities. On this basis alone, it is the responsibility of officials of the
two communities and the respective states to take joint action to achieve
and maintain air quality in keeping with the needs and desires of the
people of the area.
EVALUATION
Meteorologically and topographically the Lewiston-Clarkston area
is unique in the annals of air pollution technology, and the factors that
make the area unique are the very ones that tend to aggravate the air
pollution problem. The valley formation, particularly the rapidly rising
northerly slope, confines pollutants. An unusual frequency of low wind
speeds and a high frequency of low-level inversions provide additional
conditions conducive to pollutant accumulation. Blackening of house
paint by hydrogen sulfide on several reported occasions resulted from
simultaneous occurrences of environmental factors unfavorable for
dispersal of pollutants. Apparently, the time interval needed for such
incidents can be relatively short. Low wind speeds, combined with the
predominant east-west direction of wind flow, provide another mechanism
whereby pollution originating in either city can contaminate the other,
Appraisal and Solution - Chapter VII 129
-------
•which, in turn, creates a multijurisdictional problem that complicates
control efforts.
Meteorological data obtained at the airport station do not provide
the information necessary for interpretation and understanding of air
pollution conditions in the valley. As was demonstrated in this study,
this information is best obtained from a data-collecting system at the
Post Office in Lewiston. This also permits use of some 30 to 40 years
of past -weather records obtained in the original Weather Bureau Station
in the Post Office. Because of the unique meteorological factors, a
weather station in the valley is a necessary part of the proposed air
pollution control program.
Atmospheric concentrations of particulate and gaseous pollutants,
with the exception of sulfur dioxide, generally approached indices in-
dicative of "dirty" conditions. The data point to air pollution problems
of moderate proportions that require remedial attention by the com-
munity. The average suspended-particulate concentrations were gen-
erally large. 2>3 Suspended particulates and other pollutants in com-
bination with environmental conditions had a marked deleterious effect
on air quality. For example, the number of periods with reduced visi-
bility in the valley has increased in recent years. Since these occur
most frequently during periods of high humidity, low-level inversions,
and easterly winds, pulp mill emissions, particularly water vapor and
particulates, are implicated as responsible for adverse conditions in
the valley. To effect improvement, the community must reduce and
eliminate, wherever possible and practicable, smoke emissions from
all sources as well as water vapor emissions. For instance, uncon-
trolled and open burning of trash and garbage — both industrial and
private — in public dumps and back yards usually constitutes unnec-
essary and avoidable air pollution. Unfortunately, in the absence of
factual information, the public tends to attribute blame for such pollution
to industry exclusively. Sulfides, particularly hydrogen sulfide, and
other odoriferous gases emitted by the mill create a general nuisance
condition in the valley. The concentrations measured created a
nuisance and resulted in material deterioration, as was demonstrated
by silver tarnishing and episodes of paint blackening. Although no data
are available that precisely define the effect of hydrogen sulfide in
small concentrations on human well-being, the concentrations here
frequently exceed the minimum amount for odor detection. 2,4 The
odor is disagreeable and causes numerous complaints. Obviously, on
the basis of community reaction, air quality, with reference to odors,
needs improvement.
SOLUTION TO THE PROBLEM
Anyone developing a program for conservation and management
of the air resources of the Lewiston-Clarkston area, and for improve-
ment of air quality must consider the unique characteristics of the area,
130 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
C3PO H I 6—920—10
-------
as well as the need for joint and cooperative action by the two communi-
ties and their respective states.
The air resources management plan for a community should be
designed to maintain and achieve air quality in keeping with the needs
and desires of the people of the area and should be considered part of
the comprehensive plan for the community. In this way, it will assume
its proper role in relationship to other planning considerations such as
transportation, land use, waste disposal, water supply, etc. With a
proper air resources management plan, suitable air quality can be
achieved in an orderly fashion and at the lowest possible cost to the
community. Difficulties that might arise because of air pollution would
be minimized. 1
The method suggested for achieving satisfactory, long-range air
resources planning and management involves a number of steps. It
permits immediate joint action while the participating agencies plan the
permanent organizational structure needed to implement a program for
solution and control of the interstate problems of this air pollution
basin. The approach suggested is based on agreements reached by the
participating agencies in a conference held in Coeur d'Alene, Idaho,
July 9 and 10, 1963. In making these recommendations, the participating
agencies recognized that the protection of air resources is essential to
human well-being and orderly development of the area.
THE AIR RESOURCES MANAGEMENT COUNCIL
As a first step, an Air Resources Management Council is to be
organized and activated in 1964. The Council is to consist of repre-
sentatives of the county, municipal, and state governments involved.
The Public Health Service will act in an advisory capacity.
The Council is to act in an official capacity and is charged with the
responsibility of developing plans and programs for the Regional Air
Resources Management Agency. The manner, method, and time sche-
dule for accomplishing this goal will be determined by local and state
officials with the guidance of representatives of the public and of com-
mercial and industrial interests of the area.
As a first step the Council should obtain sufficient authority from
the two city governments, and their respective counties, for initiation
of planning, elements of which should include activities in the following
areas:
1. Surveys and studies
a. Organization and development of an air quality
monitoring network adequately financed and staffed
to permit expert measurement of the concentrations
of air pollutants and with sufficient legal authority
to execute a sound program for air quality conserva-
tion.
Appraisal and Solution - Chapter VT1 131
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b. Initiation of survey activities, particularly those
concerned with the collection and analysis of air
quality data. This activity would serve as a guide
in defining the existing air quality and provide the
basis for determining what additional data are
needed.
c. Establishment of a meteorological station in the
valley with sufficient instrumentation for measure-
ment of routine meteorological parameters and for
special measurements required to evaluate the in-
fluence of valley topography.
d. Evaluation of existing data on air pollution, as well
as industrial and nonindustrial emissions to the air,
as the basis for planning additional studies needed to
define and control air pollution. Improvement and
expansion of existing information on emissions from
industrial sources is pertinent to this program. Pro-
visions should be made to keep the inventory of
emissions current as a guide in appraising control
activities.
e. Development of a long-range program, in coopera-
tion with the medical societies of the two counties
and local physicians, for collection of information
on effects of pollution on the health of people of the
two communities.
f. Development of a method for utilizing the information
provided by the Weather Bureau Research Program
of the Division of Air Pollution, which forecasts
periods of high air pollution potential. Atmospheric
stagnation of the western United States is included
in this program. This method should be developed
in cooperation with the Weather Bureau Station at
the Nez Perce Airport and the Public Health Service.
2. Air quality guides
a. Methods for conservation and improvement of air
quality through control of process emissions should
be developed, first by assembling information on
existing practices, and second, by investigating new
methods. The Council should establish voluntary
technical committees whose function would be to
investigate control systems and advise the council
on methods of reducing emissions at a reasonable
cost to the communities and industries of the area.
Study and revision of existing performance standards
should be included.
132 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
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b. Air quality standards should be studied by the Council
to determine current and future status of air pollution
levels. The standards would provide a basis for
determining technical studies that need to be under-
taken.
c. The Council should take whatever steps appropriate
and necessary to develop such standards as part of
the planning activities and procedures of the com-
munities.
3. Legislation and administration
a. The Council should initiate collection of information
on programs and laws authorizing control of air
pollution. * This should include investigation of
methods of integrating air pollution planning with other
community planning programs. The collection of
information on anticipated future community develop-
ments should be part of the planning studies.
b. The Council, in developing its own organizational and
administrative structure, should provide for an ade-
quate public information program. This should include
adequate explanation of control measures employed,
public hearings when necessary, and periodic and
annual reports on activities. It is important that the
public be apprised of all efforts undertaken in the
community to preserve and improve air quality.
4. Regional cooperation
This study demonstrates the complexities and diffi-
culties that arise when air pollution afflicts a region
subject to several political jurisdictions — in this
case, two cities and their respective counties and
states. Action by one without the cooperation of the
others is productive only of failure. To effect
improvement under existing divided authority is
difficult. Independent legal actions by afflicted parties
provide no permanent solution for the two communities.
Industrial and commercial growth of the total economic
community requires cooperation of all parties, both
public and private. Progress in solution of the prob-
lems of this air pollution basin involves similar
cooperation.
* See Appendix D for a review of current legal authority.
Appraisal and Solution - Chapter VII 133
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The division of responsibility among levels of government
as to the control of air pollution and establishment of
control standards has been described.5
To overcome some of the current administrative diffi-
culties, the Public Health Service, in its advisory
capacity, can provide technical assistance to the joint
efforts of the communities as may be necessary and
desirable during the developmental phases of this program.
REFERENCES
1. Williams, J.D., and Schueneman, J.J. Air Resources management
planning as a part of comprehensive urban planning programs.
Unpublished paper. USDHEW. Public Health Service, Division of
Air Pollution. May 23, 1963.
2. Stern, A.C. Air pollution standards, in Stern, A.C. Air Pollution,
Vol. n. Academic Press, New York, N.Y. 1962.
3. Schueneman, J.J. Air Pollution problems and control programs in
the United States. J. Air Poll. Control Assoc., 13:116. March 1963.
4. Stern, A.C. Summary of existing air pollution standards. J. Air
Poll. Control Assoc., 14:5-15. Jan. 1964.
5. MacKenzie, V.J. The philosophy of establishing air quality criteria
as guides for the setting of air pollution control standards in the
United States. Paper presented at the Symposium on Criteria for
Air Quality and Methods of Measurement of the World Health
Organization in Geneva, Switzerland, August 6-12, 1963.
134 AIR POLLUTION IN L EWIS TON-C LARKS TON AREA
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APPENDIX A. ANALYTICAL METHODS
HIGH-VOLUME SAMPLES
TOTAL SUSPENDED PARTICULATES
Total suspended particulates were collected with a high-volume
sampler on a glass-fiber filter web. A single 24-hour sample was
collected daily at each station. Flow rate for the samples was approxi-
mately 60 cfm. The glass-fiber filters were initially dried at 60°C and
weighed. Initial and final flow rates and the total sampling time were
recorded for each sample, then the filters were again dried at 60°C for
16 to 20 hours and reweighed. From the net weight gain, total sampling
time, and average flow rate, the concentration of total suspended
particulates was calculated and expressed in micrograms per cubic
meter.
WATER-SOLUBLE SULFATES
Subsequently, the high-volume filter samples were analyzed for
water-soluble sulfates, sodium and calcium metals, and heavy metals.
A 4 percent aliquot of particulate sample was refluxed for 4 hours
with 35 milliliters of distilled water. The samples were filtered,
washed, and cooled, and the final volume was brought to 40 milliliters.
Twenty milliliters of water extract was pipetted into 25 milliliters of
95 percent glycerine-ethanol mixture (1:2 vol/vol). The solution was
mixed thoroughly and the volume adjusted to 25 milliliters. Approxi-
mately 0.25 gram of barium chloride was added and thoroughly mixed to
dissolve the crystals. The resulting suspension of barium sulfate
precipitate was allowed to stand for 40 minutes. The percent trans-
mission of suspension was read against a distilled-water blank at 500
millimicrons on a Spectronic "20" spectrophotometer. Sulfate concen-
tration was taken from a standard curve. Particulate sulfates were
reported in micrograms per cubic meter.
SODIUM
The remaining 20 milliliters of water extract was analyzed spectro-
photometrically for sodium content. Analyses were conducted on a
Beckman DU Spectrophotometer with flame photometer attachment.
Emission intensity at 589 millimicrons was measured and sodium metal
concentration taken from a standard curve. Particulate sodium was
calculated and reported in micrograms per cubic meter.
CALCIUM
Calcium analyses were run on a nitric-acid extract of the high-
volume filter. A 2 percent aliquot of the filter was refluxed with 15
Analytical Methods - Appendix A 135
-------
milliliters of 20 percent HNOs for 4 hours. The extract was filtered
and cooled, and the volume adjusted to 20 milliliters.
Calcium analysis was completed on the Beckman DU Spectrophoto-
meter equipped with a flame photometer attachment at 422 millimicrons.
A standard curve was used to give concentrations in the extract in
micrograms per milliliter. Results were extrapolated, and calcium
concentrations calculated in micrograms per cubic meter.
HYDROGEN SULFIDE
Hydrogen sulfide was determined in two ways: by the AISI strip
filter paper sampler 1 and by the colorimetric methylene blue proce-
dure. 2
AISI PROCEDURE
The AISI procedure utilized lead-acetate-impregnated paper for
the detection of H2S in the air as described by Sensenbaugh and Hem-
son. 1 Initially the air sample was drawn through teflon tubing from
the ambient air, passed through a filter to remove suspended particles,
and then over a water reservoir to humidify the air stream. The air
was then drawn through the impregnated tape, where H2S reacted with
the lead acetate to form lead sulfide, a black compound. After passing
the vacuum pump, the air was discharged through a soda-lime tube that
removed excess humidity into the enclosed face of the instrument.
This procedure maintains a slight positive pressure in the enclosed
case and prevents interference and darkening of the tape by the ambient
air.
Air was drawn through the impregnated filter tape at a known rate,
approximately 0.22 cfm, for a period of 2 hours. At the end of the
sampling period, the timing switch actuated the reset mechanism,
which automatically indexed the filter tape to a new position, and the
sampling cycle was repeated.
Tapes were marked every 2 days to show the date and time of the
sample collection, and at intervals, the exposed tapes were replaced
with fresh tapes. The optical density of the black spots was determined,
relative to the clean paper, with a transmissometer, and the concen-
tration of H2S was determined from a standard curve provided by the
instrument manufacturer.
COLORIMETRIC METHOD
was determined colorimetrically by the methylene blue proce-
dure described by Jacobs, et al. 2 A Gelman sequential sampler col-
lected 12 samples each day in an all-glass midget impinger containing
10 milliliters of a cadmium-hydroxide-absorbing solution. Samples
were collected for 115 minutes of each 2-hour period. Airflow was
136 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
controlled at a rate of 2.5 liters per minute by a critical orifice in the
vacuum line.
At the end of each 24-hour period, the impinger samples were taken
to the laboratory with a reagent blank. To each sample, 0.5 milliliter
of aminesulfuric-acid test solution and one drop of FeCls solution were
added; the sample was then mixed. The volume was adjusted to 15
milliliters with distilled water, and 30 minutes was allowed for full color
development. Percent transmission of the reagent blank was set at 100,
and the percent transmission of each sample was read at 670 millimi-
crons on a Spectronic 20 spectrophotometer with either 1/2-inch or
1-inch test tubes.
The micrograms of H2S in each sample was read from a standard
curve, and the atmospheric concentration was calculated in parts per
million.
SULFIDE DAMAGE OF PAINT AND SILVER SAMPLES
The presence of H^S and sulfur-bearing compounds in tarnished
silver plates and in darkened, lead-based paints applied to metal coupons
was determined by qualitative tests. A confirmatory test for the
presence of sulfide was performed in the following manner: concentrated
hydrochloric acid was dropped onto the surface of the exposed sample.
The evolved gases were aspirated through an absorbing reagent contain-
ing a cadmium hydroxide suspension that removed any H2S in the stream.
The presence of sulfide was determined qualitatively by the methylene
blue method. The formation of a blue color in the solution is confirma-
tion of the presence of sulfide.
REFERENCES
1. Sensenbaugh, J. D. and Hemeon, W.C.L. A low-cost sampler for
measurement of low concentration of H28. Air Repair, May 1954.
2. Jacobs, M.B., Braverman, M. M., and Hochheiser, S. Ultramicro-
determination of sulfides in air. Analytical Chemistry 29:1934.
METHOD OF TEST FOR ODOR SENSITIVITY
Three odorants were used in the November sensitivity test; vanillin,
methyl salicylate (oil of winter-green), and butyric acid. The first two
are pleasant, whereas the third, butyric acid, has a stench much like
rancid butter.
The vanillin and methyl salicylate were diluted 7/ith benzyl benzoate;
butyric acid was diluted with water. Experience showed, however, that
Analytical Methods - Appendix A 137
-------
the odor of benzyl benzoate, although slight, was sufficient to mask the
methyl salicylate and confuse many observers. In the April tests the
diluting medium was water, and the methyl salicylate was replaced with
amyl acetate, which has the pleasant odor of banana oil.
For each odorant three dilutions were prepared, one considered to
be below the normal detectable threshold, one detectable by majority of
the normal population, and a third that was higher by a factor of 10 than
the normally detectable level.
The solutions were prepared in the following ways.
Vanillin: One gram was dissolved in 250 milliliters water at 76°F.
This gave a solution of 0.4 weight-percent. This solution was used as a
stock solution for subsequent dilution to form the three test solutions,
as follows:
1. First test solution: 25 milliliters of stock solution in 100
milliliters of H^O giving 0.1 percent by weight.
2. Second test solution: 10 milliliters stock in 390 milliliters
giving 0.01 percent by weight.
3. Third test solution: 1 milliliter stock in 399 milliliters H2O
giving 0.001 percent by weight.
Distilled water was used in all cases; any stock solution could be used
although there is a limit to the solubility of vanillin in water.
Amyl Acetate: One-tenth gram was dissolved in 99.9 milliliters
water to give a stock solution of 0.1 percent by weight.
1. First test solution was the stock solution.
2. Second test solution: 10 milliliters stock in 90 milliliters
H2O giving 0.01 percent by weight.
3. Third test solution: 1 milliliter stock in 99 milliliters
H2O giving 0.001 percent by weight.
Sufficient time and mixing must be allowed to make certain the stock
solution is uniform. In the case of vanillin and amyl acetate the solution
was heated to about 120°F to aid mixing.
Butyric Acid: One-tenth gram was dissolved in 99.9 milliliters
water to give a stock solution of 0.1 percent by weight.
1. First test solution: 10 milliliters stock in 90 milliliters H2O
giving 0.01 percent by weight.
2. Second test solution: 1 milliliter stock in 99 milliliters H2O
giving 0.001 percent by weight.
3. Third test solution: 1 milliliter stock in[999 milliliters
giving 0.0001 percent by weight.
138 AIR POLLUTION IN LEWISTON- CLARKSTON AREA
-------
Preparation of the butyric acid solution requires the use of a hood
since the odor of butyric acid is very objectionable.
Each odorant was placed in an odor triangle with two blanks. The
position of the odorant in the triangle was changed from group to group.
Each vial was numbered and the observers recorded the number of the
odorous vial in each group. The observers were cautioned that some
groups might have no odorous material at all, though a set of blanks
•was included only in the April test.
The observers were asked to refrain from smoking for 1/2 hour
before the test. Questionnaires were used to obtain name, grade, and
residence location. The students were asked to note whether they had
a head cold and if so, to indicate how severe it was. Each test group
was limited to 20 persons to facilitate supervision.
Each observer was instructed to bend over the vial and "sniff"
sharply. The necessity for "sniffing" is a result of the location of the
odor-sensing organ in the nose; normally inspired air does not come in
contact with this organ. When turbulence is induced by a sudden inspira-
tion of air - "sniffing" the air is brought into contact with the sensitive
membranes. Observers were asked to wait a few seconds between
each triangle to allow any possible effects of fatigue to diminish.
DATE
OBSERVER'S NAME
OBSERVER'S NUMBER
Time
7 a.m.
4 p.m.
8 p.m.
Odor
None
1 2
Faint
3 4
Strong
5 6
Describe Odors
Do you have a cold? Yes\ ^
COMMENTS
No V~\
Figure A-l. Facsimile of odor observation card.
Analytical Methods - Appendix A
139
-------
APPENDIX B. CORRESPONDENCE
LETTER FROM CITY OF CLARKSTON TO THE DIVISION OF
AIR POLLUTION, PUBLIC HEALTH SERVICE, NOVEMBER 4, 1960.
The Mayor of Clarkston, Washington, asked for assistance in a local air
pollution problem that was, for reasons explained in the letter, too big
to be handled at either a local or state level. The Mayor cited informa-
tion describing air pollution problems and their effects on the 12,000
residents of the City of Clarkston. He pointed out that the pollution
originated near the City of Lewiston, a city of 25,000 inhabitants, in the
State of Idaho. The Mayor referred to potential health effects and sub-
mitted two exhibits to show environmental deterioration and property
damage. A third exhibit described the unique climatology and topo-
graphy of the region comprising Lewiston and Clarkston. The Mayor
emphasized that pollution originated in the adjacent State of Idaho and
that attempts to secure remedial action had not been productive.
LETTER FROM THE DIVISION OF AIR POLLUTION, PUBLIC
HEALTH SERVICE, TO THE CITY OF CLARKSTON,
NOVEMBER 15, 1960.
The Chief of the Division of Air Pollution, in reply to the Mayor's letter,
pointed out that the federal government had no regulatory authority for
control of air pollution and that existing legislation specifically stated
that it was the intention of Congress that such authority should rest with
state and local governments. He stated that because of the interstate
character of the problem the Division of Air Pollution would explore
with the appropriate state authorities their understanding of this prob-
lem and propose solutions. Furthermore, he indicated that the Public
Health Service's regional representative would be instructed to initiate
appropriate action.
LETTER TO THE IDAHO DEPARTMENT OF HEALTH FROM
PUBLIC HEALTH SERVICE OFFICE, REGION VIII,
NOVEMBER 23, 1960.
The Regional Medical Director, in his letter to the Administrator of
Health, requested an opinion about the air pollution problem and offered
the assistance of the Division of Air Pollution in further discussion of
this matter.
140 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
LETTER TO THE PUBLIC HEALTH SERVICE OFFICE, REGION Vm,
FROM THE IDAHO AIR POLLUTION CONTROL COMMISSION,
MAY1, 1961.
The Secretary of the Idaho Air Pollution Control Commission informed
the Regional Medical Director that the Public Health Service's,offer
of assistance had been presented to the Commission at its regular
meeting in Boise, Idaho, on February 13, 1961. The Commission ac-
cepted the offer of assistance and requested that a representative of
the Division of Air Pollution attend the next meeting of the Commission,
on June 5, to discuss the Public Health Service's study proposal.
LETTER TO THE DIVISION OF AIR POLLUTION FROM THE
WASHINGTON STATE DEPARTMENT OF HEALTH,
OCTOBER 2, 1961.
The Engineer in Charge of the Air Sanitation and Radiation Control
Section of the Department of Health, State of Washington, informed the
Chief of the Technical Assistance Branch, Public Health Service, that
he was basically in agreement with the outline proposed for the study
of air pollution in Clarkston. Furthermore, he designated a survey
director for the Washington State Health Department and outlined
suggestions and recommendations on various aspects of technical
study.
LETTER TO THE DIVISION OF AIR POLLUTION FROM THE
IDAHO AIR POLLUTION CONTROL COMMISSION,
OCTOBER 3, 1961.
The Chairman of the Idaho Air Pollution Control Commission indicated
to the Chief of the Technical Assistance Branch, Public Health Service,
that the proposal for a study, dated August 15, was acceptable to the
Commission and granted authorization to proceed with the study. More-
over, the Chairman added several recommendations to the proposal to
ensure maximum objectivity.
Correspondence - Appendix B 141
-------
LETTER TO THE IDAHO Am POLLUTION CONTROL COMMISSION
FROM THE DIVISION OF AIR POLLUTION,
OCTOBER 11, 1961.
The Deputy Chief of the Technical Assistance Branch, Division of Air
Pollution, in reply to the letter from the Idaho Air Pollution Control
Commission, stated that the study would be carried out as objectively as
possible and that all data would be treated in as scientific a manner as
possible. Moreover, he commented on specific questions raised by the
Commission. In addition, the Chairman of the Commission was invited
to participate in the first program session scheduled for October 19,
1961, in Lewiston, Idaho.
APPENDIX C. STATISTICAL ANALYSIS OF STUDENT
ODOR SURVEY DATA
Two basic statistical methods were used to analyze the data from
the student odor survey. The first was the analysis of variance proce-
dure, which was used when several variables were being tested for
significant differences. When two variables were to be tested against
one another, confidence limits of the population mean were used.
As described in Chapter IV, the data were compared by area and
date, by day of survey, by time of day, by sex of respondents, by incidence
of colds reported by respondents, and by odor sensitivity of the
respondents. In addition results from the November and April study
periods were compared.
AREA
The basic data used in the analysis of variance calculations are
shown in Tables C-l and C-2. A sample calculation for the November
study by area is made to illustrate the procedure. Table C-3 shows the
summations necessary for the computations.
1. Sum of squares from row means = 260^2055 - (58-543) = 3.90366
4 4 x 14
2. Sum of squares from column means = 921-96943 _ (58-543)2 = 4.65348
14 4 x 14
3. Total sum of squares from within = 80.08473 - (58-543) _ ^g 35305
4 x 14
142 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
Table C-l. PULP MILL ODORS (NOVEMBER)
o
e.
>
I
<<
O>
e-»
CD
O
l-b
g
i
i
to
Date
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Lewiston
Morning
4a
0.400b
4
0.572
6
0.600
3
0.750
1
1.000
6
0.667
5
1.000
5
0.333
0
0
0
0
1
0.333
1
1.000
3
0.750
3
1.000
Afternoon
2
0.143
5
0.385
5
0.500.
3
0.500
3
0.429
6
0.600
4
0.800
2
0.667
1
0.200
3
0.500
1
0.333
0
0
2
0.222
3
1.000
Evening
2
0.250
4
0.444
2
0.667
3
0.600
4
1.000
5
0.715
2
0.500
0
0
1
0.500
1
0.200
1
0.500
0
0
3
0.750
1
0.333
Lewiston Orchards
Morning
4
0.400
1
0.200
3
0.750
3
0.600
0
0
1
0.250
1
1.000
5
0.675
0
0
3
0.750
0
0
2
0.500
6
0.857
0
0
Afternoon
1
0.143
2
0.167
2
0.222
1
0.500
0
0
1
0.167
0
0
1
0.200
1
0.333
0
0
0
0
0
0
1
0.200
1
0.167
Evening
0
0
4
0.571
1
0.167
2
0.500
0
0
0
0
2
0.400
0
0
0
0
0
0
0
0
0
0
1
0.200
2
0.500
Clarkston
Morning
2
0.087
10
0.370
9
0.500
11
0.524
9
0.643
14
0.600
8
0.500
3
0.273
3
0.373
9
0.600
5
0.455
4
0.667
8
0.800
4
0.267
Afternoon
4
0.154
4
0.129
2
0.185
5
0.217
3
0.150
8
0.348
3
0.130
5
0.278
5
0.208
6
0.316
4
0.190
4
0.200
6
0.333
4
0.267
Evening
1
0.036
7
0.304
2
0.100
11
0.785
4
0.333
3
0.120
5
0.385
7
0.500
5
0.455
6
0.286
8
0.471
4
0.308
6
0.375
4
0.364
West Clarkston
Morning
0
0
3
0.750
3
0.600
2
0.500
0
0
2
0.667
1
0.500
0
0
2
0.667
1
0.333
1
0.333
3
1.000
2
1.000
0
0
Afternoon
0
0.143
1
0.143
1
0.143
0
0
0
0
1
0.167
0
0
1
0.333
1
0.333
2
0.500
0
0
1
0.333
1
0.250
1
0.200
Evening
0
0
1
0.200
0
0
0
0
0
0
1
0.200
1
0.333
0
0
4
1.000
0
0
2
0.667
3
0.600
1
0.250
1
0.250
a First entry is actual number of positive pulp mill odor responses (Type 1).
b Second entry is proportion of positive to total odor responses.
-------
Table C-2. PULP MILL ODORS (APRIL)
O
t-1
r
IT1
CQ
H
i
O
f
CQ
H
O
5!
>
»
H
Date
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Lewiston
Morning
Oa
Ob
1
0.250
2
0.500
4
0.364
7
0.778
2
0.400
0
0
1
0.333
1
0.167
2
0.667
2
0.400
7
0.875
10
0.259
0
0
Afternoon
0
0
1
0.200
2
0.400
3
0.300
1
0.111
3
0.333
1
0.200
2
0.500
2
0.500
1
0.111
0
0
2
0.333
0
0
0
0
Evening
1
0.167
0
0
1
0.250
4
0.333
0
0
3
0.375
2
0.286
1
0.500
1
0.333
0
0
2
0.250
1
0.200
0
0
0
0
Lewlston Orchards
Morning
0
0
4
1.000
0
0
1
0.167
2
0.500
2
0.500
0
0
0
0
1
0.250
1
0.500
0
0
2
1.000
2
0.400
2
0.667
Afternoon
0
0
0
0
0
0
0
0
3
0.429
1
0.200
1
0.143
0
0
0
0
0
0
1
0.200
1
0.333
2
0.400
0
0
Evening
0
0
0
0
0
0
0
0
1
0.200
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0.200
1
0.333
Clarkston
Morning
2
0.333
5
1.000
4
0.667
7
0.875
3
0.600
3
0.750
3
0.429
3
1.000
4
0.572
3
0.750
5
0.715
9
0.900
4
0.800
1
0.250
Afternoon
4
0.667
2
0.154
4
0.200
3
0.429
0
0
0
0
4
0.572
3
0.600
1
0.250
4
0.444
3
0.500
5
0.625
2
0.222
1
0.333
Evening
1
0.200
2
0.429
2
0.250
6
0.667
0
0
1
0.333
6
0.750
4
0.800
5
0.625
3
0.750
4
0.667
5
0.625
3
0.500
1
0.143
West Clarkston
Morning
0
0
0
0
0
0
0
0
1
1.000
1
0.500
1
1.000
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Afternoon
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Evening
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1.000
0
0
0
0
0
0
1
1.000
0
0
0
0
a First entry is actual number of positive pulp mill odor responses (Type 1).
k Second entry is proportion of positive to total odor responses.
-------
Table C-3. ANALYSIS OF VARIANCE TABLE BY AREA
AND DATE — NOVEMBER
Date
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Total
Lewiston
0.793
1.401
1.797
1.850
2.429
1.982
2.300
1.000
0.700
0.700
1.166
1.000
1.722
2.333
21.143
Lewiston
Orchards
0.543
0.938
1.139
1.600
0
0.417
1.400
0.875
0.333
0.750
0
0.500
1.257
0.667
10.419
Clarkston
0.277
0.803
0.785
1.526
1.126
1.068
1.015
1.051
1.036
1.202
1.116
1.175
1.508
0.898
14.586
West
Clarkston
0.143
1.093
0.743
0.500
0
1.034
0.833
0.333
2.000
0.833
1.000
1.933
1.500
0.450
12.395
Total
1.756
4.235
4.434
5.476
3.555
4.501
5.548
3.259
4.069
3.485
3.282
4.608
5.987
4.348
58.543
4. Analysis of variance
Row means
Column means
Residual
Total
Sum of squares
3.90366
4.65348
10.32611
18.88325
df
13
3
39
55
Mean square
0.30028
1.55116
0.26477
= L13412
„ 1.55116 c
Fc= 06477 = 5'
(13.39)= 1.94
0.95
= 2.91
There is, therefore, no significant difference for the pulp mill odor
responses for the days of the November survey. There is, however, a
significant difference among the areas for the proportion of pulp mill
odors reported during the survey period.
Statistical Analysis of Odor Data - Appendix C
145
-------
The calculations for the April study are similar, and the tabulation
and summations are presented in Table C-4.
The results show no significant differences among the days of the
April study. Again, there is a significant variation among the four areas.
Table C-4. ANALYSIS OF VARIANCE TABLE BY AREA
AND DATE — APRIL
Date
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Total
Lewiston
0.167
0.450
1.150
0.997
0.889
1.108
0.486
1.333
1.000
0.778
0.650
1.408
0.250
0
10.666
Lewiston
Orchards
0
1.667
0
0.167
1.129
0.700
0.143
0
0.250
0.500
0.200
1.333
1.000
1.000
8.089
Clarkston
1.200
1.583
1.117
1.971
0.600
1.083
1.751
2.400
1.447
1.944
1.882
2.150
1.522
0.726
21.376
West
Clarkston
0
0
0
0
1.000
0.500
1.000
1.000
0
0
0
1.000
0
0
4.500
Total
1.367
3.700
2.267
3.135
3.618
3.391
3.380
4.733
2.697
3.222
2.732
5.891
2.772
1.726
44.631
Three other odor types were compared by areas by use of a
statistical test, "Student t test," for significance. The odors were
smoke and wood smoke (Type 2), burning leaves (Type 3), and
rubbish and burning trash (Type 7). Table C-5 shows the essential
information for the analyses. A sample calculation is carried out
for the Type 7 odors during November.
In November, there were significant variations in the Type 2 and
Type 3 odors by area. In April, Type 2 odors showed significant dif-
ferences by area where Type 3 and Type 7 odors showed none.
TIME
To analyze pulp mill odors by time of day, the analysis of variance
procedure was used. Table C-6 shows the essential information for the
November and April study periods.
146
AIR POLLUTION IN LEWISTON-CLARKSTON AREA
GPO 6iH6r-a20-ll
-------
Table C-5. RESPONSES TO TYPE 2, 3, AND 7 ODORS -
NOVEMBER AND APRIL
Lewiston
Lewiston
Orchards
Clarkston
West
Clarkston
Type 2 odors
Nov. Apr.
76
79
227
41
39
41
28
14
Type 3 odors
Nov. Apr.
19
22
92
8
4
10
7
0
Type 7 odors
Nov. Apr.
5
12
68
12
11
4
45
5
Total positive
responses
Nov. Apr.
944
935
1,635
289
1,072
726
1,167
204
Sample calculations with conclusion for Type 7 odors during December
follow:
X = No. of Type 7 responses per 1,000 positive responses
Lewiston
Lewiston
Orchards
5.3
12.8
2x2 = 3,506.6
Clarkston 40.0
West Clarkston 41.5
•t Y — A* — **y«*j
= 24.8
2. (n-1) s2 = Zx2 -
ti
= 3,506.6- 1/4 (99.3)2 = 13.8
3. s = T/s2" = VTO = 3.72
3 72
4. /A = X ± t0.95-tff = 24.8 ± 3.182 V4~
= 24.8 ± 5.9
5. 18.9 < P- <30.7
6. Conclusion: There is a significant difference at the 95 percent
confidence level in the responses to Type 7 odors among the four
areas during the November study period.
Statistical Analysis of Odor Data - Appendix C
147
-------
Table C-6. RESPONSE TO PULP MILL ODORS BY TIME OF DAY
o
IT1
tr1
C
a
i
f
W
CO
H
i
S3
November
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Total
Morning
0.887
1.892
2.450
2.374
1.643
2.184
3.000
1.281
1.040
1.683
1.121
3.167
3.407
1.267
27.396
Afternoon
0.583
0.824
1.050
1.217
0.579
1.282
0.930
1.478
1.074
1.316
0.523
0.533
1.005
1.634
14.028
Evening
0.286
1.519
0.934
1.885
1.333
1.035
1.618
0.500
1.955
0.486
1.638
0.908
1.575
1.447
17.119
Total
1.756
4.235
4.434
5.476
3.555
4.501
5.548
3.259
4.069
3.485
3.282
4.608
5.987
4.348
48.543
April
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Total
Morning
0.333
2.250
1.167
1.406
2.878
2.150
1.429
1.333
0.989
1.917
1.115
2.775
1.450
0.917
22.109
Afternoon
0.667
1.021
0.600
0.729
0.540
0.533
0.915
1.100
0.750
0.555
0.700
1.291
0.622
0.333
10.356
Evening
0.367
0.429
0.500
1.000
0.200
0.708
1.036
2.300
0.958
0.750
0.917
1.825
0.700
0.476
12.176
Total
1.367
3.700
2.267
3.135
3.618
3.391
3.380
4.733
2.697
3.222
2.732
5.891
2.772
1.726
44.631
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The results for the analysis show that in both November and April
the responses to pulp mill odors showed significant variations, with
morning response greater than average and afternoon and evening re-
sponses less than average.
HUMAN VARIABLES
Sex of Respondent
Confidence limits of the population means were used to evaluate the
difference in odor sensitivity between male and female respondents. The
data are shown in Table C-7. The calculations are also shown for
November.
Table C-7. ODOR SENSITIVITY TEST RESULTS -
NOVEMBER AND APRIL
Test
score
0
1
2
3
4
5
6
7
8
9
Frequency of occurrence
November
Male
0
1
2
11
14
12
7
2
1
0
Female
0
1
8
11
10
16
17
7
0
0
April
Male
0
0
0
2
0
3
19
10
8
1
Female
0
0
0
0
2
8
16
14
15
8
Sample calculation (November data)
Male
1. Zf = 50
2. Zf x = 218
3. Zf x2 = 1046
4. X
where f = number of respondents with a given test score
x 218
50
= 4.36
Statistical Analysis of Odor Data - Appendix C
149
-------
. (n-1) s2 = It x2 - i ( Zf x)2
49 s2 = 1046 - ± (218)2
Of
s2 = 1.96
s = 1.40
6- /* = X +
AI = 4.36
/u. = 4.36 + 0.39
7. 3.97 ^ P- S4.75
Female
1. Zf = 70
2. Zf x = 321
3. Zf x2 = 1647
v _ Zf x
4. X -
Y - 321
~70~
X = 4.59
Since the average odor sensitivity for females falls within the range of
the male odor sensitivity no statistically significant difference was
apparent for the sexes during the November study period. The same
conclusion follows an analysis of the April sensitivity test results.
Incident of Colds
The same procedure as above was used in analyzing the effect of the
incidence of colds in the respondents. The results show that colds had
no significant effect on the odor sensitivity of the respondents for either
study period. The pertinent data are shown in Table C-8.
150 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
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Table C-8. FREQUENCY OF COLDS VERSUS ODOR
SENSITIVITY TEST SCORE - APRIL
Test score
0
1
2
3
4
5
6
7
8
9
10
Cold
0
0
0
1
0
5
10
3
5
2
0
No cold
0
0
0
2
2
7
31
24
20
10
1
APPENDIX D. LEGAL BASIS FOR AIR
POLLUTION CONTROL
This portion of the report considers the legal remedies available
to public authorities to cope with air pollution problems arising in the
States of Idaho and Washington, particularly the Lewiston-Clarkston
area.
IDAHO
SPECIFIC LEGISLATION TO CONTROL AIR POLLUTION
Under the Idaho Air Pollution Control Act of 1959 the Air Pollution
Control Commission has authority to abate air pollution (Sec. 39-2908
Idaho Code). Although the Act authorizes the Commission to adopt rules
and regulations to control and prohibit air pollution throughout the State
or in affected areas of the State, the Commission has received no
appropriations (except small sums for travel) since its creation, and
to date no action has been taken by the Commission to implement its
authority.
"Air Pollution" is defined in the Idaho Air Pollution Control Act of
1959 as "the presence in the outdoor atmosphere of substances put
there by man in concentration sufficient to cause an unreasonable inter-
ference with human, plant or animal life, or the reasonable use of
property." (Sec. 39-2902 I.C.).
Neither the Idaho Air Pollution Control Act of 1959 nor regulations
adopted pursuant to it affect ordinances or regulations adpoted by any
municipality, county, or board of health where such local ordinances
are not inconsistent with the Act and regulations thereunder (Sec. 39-
2922, Idaho Code).
Legal Basis for Control - Appendix D 151
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Existing civil and criminal remedies for actions that may also
violate rules or regulations under the Act are preserved, and functions
vested in the State Board of Health by other legislative Acts are not
affected (Sec. 39-2921, Idaho Code).
The following sections of the Idaho Code relate to the control of
public nuisances:
(1) Sec. 18-5901. "Public nuisance defined—Anything which is
injurious to health, or is indecent, or offensive to the senses,
or an obstruction to the free use of property, so as to inter-
fere with the comfortable enjoyment of life or property by an
entire community or neighborhood, or by any considerable
number of persons, or unlawfully obstructs the free passage
or use, in the customary manner, of any navigable lake, or
river, stream, canal or basin, or of any public park, square,
street or highway, is a public nuisance." (See also Sec. 52-101,
I.C.)
(2) Sec. 18-5903. "Punishment for nuisance.—Any person who
maintains or commits any public nuisance the punishment for
which is not otherwise prescribed, or who wilfully omits to
perform any legal duty relating to the removal of a public
nuisance, is guilty of a misdemeanor."
(3) Sec. 52-202. "Remedies—The remedies against a public
nuisance are:
(i) Indictment or information
(ii) A civil action, or
(iii) Abatement."
(4) Sec. 52-205. "Abatement by public body or officer—A public
nuisance may be abated by any public body or officer authorized
thereto by law."
The foregoing statutory provisions appear to authorize action to
abate air pollution that constitutes a public nuisance by (1) municipal
authorities (Calvin v. Appleby, 78 Idaho 457, 305 P. 2d 309; Boise City
v. Sinsel, 72 Idaho 145, 190 P. 2d 681) and (2) and County Board of
Health of the County in which the nuisance occurs (Sec. 39-303 Idaho
Code).
Under other provisions of the Idaho Code (Sec. 39-101 (14), Sec.
39-101, (13(a)) the Idaho State Board of Health appears to be authorized
to abate public nuisances.
CITY CHARTER PROVISIONS - LEWISTON, IDAHO
The following provisions of the City of Lewiston Charter (Idaho
Sess. Laws 1907, H.B. No. 121, p. 349) relate to the control of nuisances
and dense smoke.
152 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
-------
1. Section 86 authorizes the City Council "to declare, prevent and
abate nuisances on public or private property, and the causes
thereof."
2. Under Section 102, the City Council is authorized "To control,
regulate and prohibit the emission of dense smoke from
chimneys and chimney stacks of buildings, manufactories,
locomotives, or engines within the city; and to regulate, con-
trol, prohibit, and prevent the emission of dense smoke in
any manner in said city."
Under these state law provisions and provisions of the City of
Lewiston Charter, authority exists for the City to take action to abate
air pollution that originates within the City and constitutes a public
nuisance or consists of dense smoke.
Under Idaho law, a municipality also may sue to enjoin a public
nuisance originating outside of its jurisdiction - Village of American
Falls v. West (Idaho 1914) 142 Pac. 42.
WASHINGTON
Specific Legislation to Control Air Pollution
The Washington Air Pollution Control Act of 1957 (Sec. 70.94.010,
R.C.W.) gives cities, towns, and counties authority to adopt and enforce
air pollution control ordinances after a public hearing and a resolution
by the governing body declaring the necessity for controlling air pol-
lution (Sec. 70.94.050, R.C.W.).
"Air Pollution" is defined as "the presence in the outdoor atmos-
phere of substances put there by man in concentration sufficient to
cause an unreasonable interference with the comfort, safety or health
of man; or the reasonable use and enjoyment of his property." (Sec.
70.94.030, R.C.W.)
Clarkston has not yet acted under this grant of authority.
The following provisions of the Washington Code relate to the control
of public nuisances:
A public nuisance is an offense against the state (Sec. 9.66.010,
R.C.W.) and is punishable by a fine of not more than $1,000 (Sec. 7.48.
250). Remedies against a public nuisance are "indictment or information,
civil action or abatement." (Sec. 7.48.200.) A public nuisance may be
abated by a public body or officer thereto authorized by law (Sec. 7.48.200).
The county health officer has authority to abate any public nuisance with-
in his geographical jurisdiction (Sec. 70.06.03, R.C.W.).
Legal Basis for Control - Appendix D 153
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City Ordinance - Clarkston, Washington
The City of Clarkston Zoning Ordinance, effective April 28, 1956,
establishes performance standards for permitted uses in the C (commer-
cial) zone (Sec. 1.20.021). These standards, in essence, prohibit
emissions of (1) air contaminants as dark or darker than No. 2 Ringel-
mann or air contaminants of equal or greater opacity (2) particulate
matter or dust in excess of 0.3 grain per cubic foot, (3) obnoxious
odors, (4) sulfur dioxide and hydrogen sulfide in excess of 0.5 ppm, and
nitrous fumes in excess of 5 ppm, and (5) any material that in substance
causes a public nuisance.
Substantially similar standards are established for the M (manu-
facturing) zone (Section 1.21.020).
Legal proceedings by a municipality, a county, or state to abate
air pollution whose source is in another state is not wholly without
precedent - Georgia v. Tennessee Copper Co. (1907) 201 U.S.230, 27
S.Ct. 618. Although such an action by a municipality, county, or state
affected by a nuisance may be viewed as a possibility, however, no
assurance can be given that an ultimate successful conclusion can be
reached.
FEDERAL CLEAN AIR ACT OF DECEMBER 17, 1963
Section 5 of the Federal Clean Air Act (P.L. 88-206) enacted
December 17,1963, provides that in the case of air pollution that is
alleged to endanger the health or welfare of persons in a state other
than that in which the discharge originates a conference of the air
pollution control agencies involved shall be called by the Secretary of
Health, Education, and Welfare at the request of the governor of any
state, a state air pollution control agency, or (with the concurrence of
the governor and the state agency) the governing body of any municipality.
Following the conference, if effective progress is not being made
toward abatement of the air pollution and the health or welfare of any
persons is being endangered, the Secretary will recommend remedial
action. If appropriate action is not taken within the time allowed by the
Secretary (not less than 6 months) further procedures are authorized
before a hearing board and ultimately the Secretary is authorized to
request that the Attorney General bring a suit on behalf of the United
States to secure abatement of the air pollution.
154 AIR POLLUTION IN LEWISTON-CLARKSTON AREA
GPO 81 6—92O—1 2
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BIBLIOGRAPHIC: A study of air pollution in the inter-
state region of Lewiston, Idaho, and Clarkston, Wash-
ington. PHS Publ. No. 999-AP-8. Dec. 1964. 154 pp.
ABSTRACT: As a result of an increasing number of com-
plaints from citizens about reduced visibility, damage
to house paint, tarnishing of silver, undesirable odors,
and suspected effects of air pollution on health, Idaho
and Washington and Lewiston and Clarkston officials
requested assistance from the U. S. Public Health
Service. Subsequently, the Public Health Service, the
two states, and the two cities agreed to undertake a
cooperative study; the two cities participated in the
study. The purpose of the study was to determine the
nature and extent of air pollution in the two-city
area and to assemble information to be used as a
basis for technical and official action needed to con-
serve air quality in the area.
Because of its unique valley location, the two-city
area is susceptible to meteorological conditions
ACCESSION NO.
KEY WORDS:
BIBLIOGRAPHIC: A study of air pollution in the inter-
state region of Lewiston, Idaho, and Clarkston, Wash-
ington. PHS Publ. No. 999-AP-8. Dec. 1964. 154 pp.
ABSTRACT: As a result of an increasing number of com-
plaints from citizens about reduced visibility, damage
to house paint, tarnishing of silver, undesirable odors,
and suspected effects of air pollution on health, Idaho
and Washington and Lewiston and Clarkston officials
requested assistant e from the U. S. Public Health
Service. Subsequently, the Public Health Service, the
two states, and the two cities agreed to undertake a
cooperative study; the two cities participated in the
study. The purpose of the study was to determine the
nature and extent of air pollution in the two-city
area and to assemble information to be used as a
basis for technical and official action needed to con-
serve air quality in the area.
Because of its unique valley location, the two-city
area is susceptible to meteorological conditions
ACCESSION NO.
KEY WORDS:
BIBLIOGRAPHIC: A study of air pollution in the inter-
state region of Lewiston, Idaho, and Clarkston, Wash-
ington. PHS Publ. No. 999-AP-8. Dec. 1964. 154 pp.
ABSTRACT: As a result of an increasing number of com-
plaints from citizens about reduced visibility, damage
to house paint, tarnishing of silver, undesirable odors,
and suspected effects of air pollution on health, Idaho
and Washington and Lewiston and Clarkston officials
requested assistance from the U. S. Public Health
Service. Subsequently, the Public Health Service, the
two states, and the two cities agreed to undertake a
cooperative study; the two cities participated in the
study. The purpose of the study was to determine the
nature and extent of air pollution in the two-city
area and to assemble information to be used as a
basis for technical and official action needed to con-
serve air quality in the area.
Because of its unique valley location, the two-city
conditions
ACCESSION NO.
KEY WORDS:
-------
conducive to pollutant accumulation. Either city can
contaminate the other, and this creates a multijuris-
dictional problem that requires joint and cooperative
action to control air pollution. As a first step to
solve the problem, an Air Resources Management
Council consisting of county, city, and state officials
is to be organized. This council -will be responsible
for planning surveys and studies to determine air
quality guides and legislation and administration nec-
essary to control air pollution in this multijurisdictional
area. The Public Health Service in its advisory
capacity will provide technical assistance.
conducive to pollutant accumulation. Either city can
contaminate the other, and this creates a multijuris-
dictional problem that requires joint and cooperative
action to control air pollution. As a first step to
solve the problem, an Air Resources Management
Council consisting of county, city, and state officials
is to be organized. This council will be responsible
for planning surveys and studies to determine air
quality guides and legislation and administration nec-
essary to control air pollution in this multijurisdictional
area. The Public Health Service in its advisory
capacity will provide technical assistance.
conducive to pollutant accumulation. Either city can
contaminate the other, and this creates a multijuris-
dictional problem that requires joint and cooperative
action to control air pollution. As a first step to
solve the problem, an Air Resources Management
Council consisting of county, city, and state officials
is to be organized. This council will be responsible
for planning surveys and studies to determine air
quality guides and legislation and administration nec-
essary to control air pollution in this multijurisdictional
area. The Public Health Service in its advisory
capacity will provide technical assistance.
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