LEWISTON, IDAHO,-CLARKSTON, WASHINGTON
AIR POLLUTION ABATEMENT ACTIVITY
U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE
Public Health Service
-------
TECHNICAL REPORT
lEWISTON, IDAHO-CLARKSTON, WASHINGTON
AIR POllUTION ABATEMENT ACTIVITY
u.s. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE
Public Health Service
National Center for Air Pollution Control
February 1967
-------
CONTENTS
Secti on I Summary and Conc 1 us ions. . . . . . . . . . . . . . . . . . . . . . . 1
Section II Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4
Section III Review of Past Studies. . . . . . . . . . . . . . . . . . . . . . . . . . 7
A Study of Air Pollution in the Interstate Region of Lewiston, Idaho,
and Clarkston, Washington. . . . . . . . . 7
Community Perception of Air Quality - An Opinion Survey in Clarkston, Washington. . . 9
An Air Quality Study in the Vicinity of Lewiston, Idaho, and Clarkston, Washington. . 9
Section IV - Inventory of Community Atmospheric Emissions. . . . . . . . . . . . . . . . 11
Industrial Process Emissions Excluding Potlatch Forests, Inc. . . . . . . . . . . . . . 11
Lumbering Operations. . . .". . . . . . . . . . . . . . . . . . . . . . . . 11
Asphalt Mix Plants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Food Processing Plants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Concrete Mixing and Grain Handling. . . . . . . . . . . . . . . . . . . . . . . . . 13
Fue 1 Usage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Non-Industrial Fuels. . . . . . . . . . . . . . . . . . . . . . . . 13
Industrial Fuels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Refuse Disposal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Vehicular Emissions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Summary of Community Emissions (Excluding Potlatch Forests, Inc.) . . . . . . . 16
Section V - Atmospheric Emissions from Potlatch Forests, Inc., Kraft
. ~ Pulp Mill and Lumber Mill. . . . . . . . . 19
Revi ew of Kraft Pu1 p Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Description of Potlatch Forests, Inc., Pulp Mill Processes and their Emissions. . . 20
Digestion and Blow System. . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Multiple-Effect Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Direct-Contact Evaporators and Recovery Furnaces. . . . . . . . . . . . . . . . . 22
Smelt Tank, Causticizing Tank, and Lime Kiln. . . . . . . . . . . . . . . . . . . 24
Steam Boil er P1 ants. . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Other Sources of Atmospheric Pollution. . . . . . . . . . . . . . . . . . . . . . 25
Summary of Pulp r~il1 Emissions. . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Section VI - Discussion of Control Technology. . . . . . . . . . . . . . . . . . . . 27
Digester and Blow System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Multiple-Effect Evap~ration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Direct-Contact Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Recovery Furnaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Personne 1 Respons i bil iti es ....................... . . 30
Control of Community Emissions. . . . . . . . . . . . . . . . . . . . . . . 30
-------
Section VII Meteorology............................... 31
Effects of Terrain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Effects of Clouds, Fog, and Snow Cover. . . . . . . . . . . . . . . . . . . . . . . . 31
Wind Speed and Direction. . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Temperature Inversions. . . . . . . . . . . . . . . . . . . . 33
Fumigation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Episodes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Section VIII - Estimated Concentrations of Air Pollutants. . . . . . . . . . . . . . . 41
Odorous Gases. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Particulates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Water Vapor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Genera 1 Comment. . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Section IX - Effects of Odors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Section X - Deterioration of Materials. . . . . . . . . . . . . . . . . . . . 49
5i lver Tarnishing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Paint Damage and Steel Corrosion. . . . . . . . . . . . . . . . . . . . .. 50
References. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 53
Appendix A - Tri-County Air and Water Quality Control Committee Charter. . . . . . . 55
Appendix B Pilot Balloon Observations, Lewiston, Idaho, October, 1966 . . . . . .. 57
-------
LEWISTON, IDAHO-CLARKSTON, WASHINGTON
AIR POLLUTION ABATEMENT ACTIVITY
SECTION I-SUMMARY AND CONCLUSIONS
Air pollution in Lewiston, Idaho, and Clarkston, Wash., has been a matter of concern to
residents of the bi-state area for the past several years. There are numerous sources of air
pollution in the community; the largest of these is the Potlatch Forests, Inc., kraft pulp mill
located just east of Lewiston. ~10st complaints about air pollution have been directed at this
mi 11.
Investigations of air pollution in the community have been concerned with air quality,
meteorology, sources of pollutants, and various effects of air pollution. The interstate
movement of pollutants, particularly odorous gases emitted by the pulp mill in Idaho and trans-
ported to Clarkston, Wash., has been demonstrated. In a public opinion survey in Clarkston,
Wash., more than 90 percent of the persons interviewed perceived air pollution in the
community as a malodor problem.
One investigation conducted jointly by Federal, state and local agencies resulted in
recommendations in 1963 that a regional air resource management council be established in 1964.
It was recommended that this agency have certain responsibilities, including surveillance of
air quality and planning for control of pollutant emissions. By December of 1965 no such
agency had been organized and the Secretary of Health, Education, and Welfare initiated an
interstate air pollution abatement action.
Personnel of the Idaho Department of Health, the Washington State Department of Health,
and the Public Health Service, visited the Potlatch Forests, Inc., pulp mill in May 1966.
Potlatch Forests, Inc., gave full cooperation and provided a detailed report on emissions of
air pollutants from its pulp and paper mills, and its wood products operations at Lewiston.
The Company reported emissions amounting to about 1,800 pounds of hydrogen sulfide, 2,500
pounds of mercaptans, and 1 ,000 pounds of organ i c sulfi de gases per day from the pu 1 p mi 11 ;
about 23,000 pounds of particulates, consisting mostly of sodium sulfate and sodium carbonate
per day, from the mill's recovery furnaces; and an average of about 9,700 tons of water vapor
per day from all operations.
An inventory of air pollutant emissions from sources other than Potlatch Forests, Inc.,
was conducted in the Lewiston-Clarkston area in the fall of 1966. Calculated daily emissions
of selected pollutants included about 4,000 pounds of particulates, 100,000 pounds of carbon
-------
2
monoxide, and more than 20,000 pounds of hydrocarbons. The particulates are generated
primarily by industrial processes and by burning of fuel and refuse; carbon monoxide and
hydrocarbons come, for the most part, from motor vehicles. About two-thirds of the community
emissions are released in Idaho and about one-third in Washington.
The valley topography of the Lewiston-Clarkston area tends to channel winds in easterly
and westerly directions. The predominant wind direction is east; winds from this direction
occur more than one-fourth of the time on an annual basis. Wind speeds are very low; the
annual average in Lewiston is less than 4 miles per hour. Temperature inversions tend to
confine air pollutants in the valley, and they occur frequently. High concentrations of air
pollutants occur at the surface when layers of pollutants which have been carried over the
cities are brought to the ground during inversion break-up. Hydrogen sulfide concentrations
in Clarkston were calculated by using meteorological diffusion equations and emission rates
reported by Potlatch Forests, Inc. The calculated concentrations agree well with the 10 to
15 parts per billion actually measured in earlier investigations.
The results of various technical investigations of air pollution, studies of meteorology,
and determinations of pollutant emissions in the Lewiston-Clarkston area lead to the following
conclusions:
1.
Terrain configuration and prevailing winds in the Lewiston, Idaho-Clarkston, Wash.,
area result in the transport of air pollutants alternately from either of the states
to the other. The confining effect of the valley walls, the high frequency of
temperature inversions, and the low average wind speed in the area all favor the
accumulation of pollutants in the valley.
2.
A number of sources in the area emit air pollutants. The major source, and the only
one that emits large quantities of the odorous gases (hydrogen sulfide, mercaptans,
and organic sulfides) that are characteristic of kraft pulping operations, is the
Potlatch Forests, Inc., kraft pulp mill. Odorous gases from this mill are transported
across the state boundary from Idaho to Washington.
3.
Particulate material, consisting primarily of sodium sulfate, emitted
mill recovery furnaces can, under certain circumstances, cause damage
of paint on ferrous metals and expose the metals for corrosion.
from the pulp
to some types
4.
Technology is adequate to control the escape of pollutants from kraft pulping
processes to the atmosphere.
5.
Potlatch Forests, Inc., has made efforts to control emissions of pollutants
pulp mill at Lewiston, and plans for additional effort have been reported.
Accomplishments to date have been inadequate to control the problem.
from its
6.
Industrial incineration
to air pollution in the
emissions of pollutants
and the burning of refuse produce smoke which contributes
community. Means are available to reduce or eliminate
from such sources.
-------
SE-Cl"ION II-INTRODUCTION
The cities of Clarkston, Wash., and Lewiston, Idaho, are located on opposite banks of the
Snake River at its confluence with the Clearwater River on the boundary between Washington and
Idaho. These two cities, and their adjacent unincorporated areas comprise a bi-state community
of some 39,000 people. Of these 39,000 people, approximately 26,000 live in Idaho and 13,000
in Washington (Figure 1).
o
I
mi I es
Clarkston Heights
IDAHO
Lewiston
Ai rport
Figure 1-
Lewiston-Clarkston st~dy area.
Asotin County, Wash., in which Clarkston is located, has a population of about 11,400; and
Nez Perce County, Idaho, in which Lewiston is located, has a population of abo~t 29,000. Adjacent
counties nearest to Lewiston and Clarkston are Whitman County, Wash., with a population of about
34,000, and Latah County, Idaho, with a population of 22,300. The trading area served by Lewiston
and Clarkston has a total estimated population of about 110,000 people.
Lewiston and Clarkston are set in a rather narrow valley oriented east and west with a range
of hills on the north slopinq abruptly to about 2,000 feet above the valley floor. To the south,
the terrain rises more qradually to a flat bench about 700 feet above the valley.
The area is important as an agricultural center. The manufacture of forest products is,
however, the largest single cateqory of business. There are several lumber mills in the area.
3
-------
4
Just to the east of Lewiston, about 2 miles east from Clarkston, are the Potlatch Forests, Inc.,
kraft pulp mill, paper mill, and wood products plant. The pulp mill has an average current produc-
tion rate of 755 tons of pulp per day. It has for several years been the object of complaints
regarding air pollution in the area.
By letter of November 4, 1960, to the Chief, Division of Air Pollution, Public Health Service,
the Mayor of Clarkston requested assistance in resolving the air pollution problem of the
C1arkston-Lewiston area. In response the Public Health Service communicated with the air pollution
agencies of the States of Washington and Idaho; subsequent events resulted in agreement to under-
take a cooperative study of the area's air pollution problem by Federal, State, and local agencies.
During the period October 1961 to April 1962 this study was conducted; the following agencies
participated:
The City of Clarkston, Wash.
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
The study report, entitled "A Study of Air Pollution in the Interstate Region of Lewiston, Idaho,
and Clarkston, Washington," was published by the Public Health Service, U. S. Department of Health,
Education, and Welfare, in 1964.11 In becoming signatory to the report, the Idaho Air Pollution
Control Commission took exception and withheld its approval from portions of the report. The
Commission did, however, give its wholehearted and unqualified concurrence and endorsement to the
recommendations of the report. These recommendations, which were agreed to by the participating
agencies at the conference held in Coeur d'A1ene, Idaho, July 6-10, 1963, follow:
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.
-------
5
(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 deterr.1ined 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.
By December 1965 implementation of the recommendations had not been initiated and concel'n for
the air pollution problem continued among residents of the area.
Pursuant to the provisions of Section 5 of the Clean Air Act, Public Law 88-206 (42 U.S.C.
1857d et~) the Secretary of Health, Education, and Welfare, on December 23,1965, ~equested
that representatives of the air pollution control agencies of the States of Washingtoll and Idaho
consult with Department representatives concerning the problem of air pollution in the area. In
his letter the Secretary stated that on the basis of reports, surveys, and studies, he has reason
to believe that air pollution originating in Idaho is endangering the health and welfare of persons
in Clarkston, Wash. TlTe consultation was held in Seattle, I'!ash., on February 7, 1966. Following
thi s consultati on, arrangements were made by the Idaho Department of Health for techn; cal representa-
ti ves of the Pub 1 i c Health Servi ce, U. S. Depa rtment of Health, Educati on, and We lfne, the
Washington State Department of Health, and the Idaho Department of Health to examine the Potlatch
Forests, Inc., kraft pulp mill at Lewiston. This examination was made on May 19,1966. At the
time of this visit officials of Potlatch Forests, Inc., agreed to supply to the Idaho Department
of Health, for forwarding to the Public Health Service, information on emissions of air pollutants
from the Lewiston operations. In response to questions developed by the Public Health Service,
Potlatch Forests, Inc., assembled and supplied detailed information on emissions to the Idaho
Department of Health in August 1966. The excellent cooperation of the Potlatch Forests, Inc., in
permitting the visit to its faciT ities and in supplying information on emissions of ai r pollutants
from its Le~iston operations is acknowledged.
About March 1, 1966, a Tri-County Air and Water Quality Control Committee was organized. The
concern of this Committee is maintenance of the qual ity of ai r and water resources in Whitman and
Asotin Counties, Wash., and Nez Perce County, Idaho. The Committee is composed of nine persons,
one officially appointed- by the qoverning body of each of the following:
-------
6
Whitman County, Wash.
Asotin County, Wash.
Nez Perce County, Idaho
Port of Lewiston
Port af Clarkston
Port of Whitman County
Lewiston, Idaho
Clarkston, Wash.
Asotin, Wash.
The Charter of this Committee states that unacceptable levels of air and water pollution
exist in portions of the tri-county area, and that the Committee shall undertake action leading
to recommendations for contro11inq and abating such pollution. The function of the Committee
is advisory only; requlation and enforcement actions shall be the responsibility of the parent
municipal corporations or appropriate leqis1ative bodies. The Charter of the Tri-County Air
and Water Duality Control Committee is reproduced in Appendix A of this report.
Emissions of air pollutants occur in the vicinities of Lewiston and Clarkston from sources
other than Potlatch Forests, Inc. An inventory of emissions from industrial, commercial,
municipal, and domestic sources was conducted by Public Health Service personnel during the
autumn of 1966. Durinq this same period, special meteoro1oqical observations were made in the
area by Public Health Service personnel. Results of both of these efforts are contained in this
report.
-------
SECTION III-REVIEW OF PAST STUDIES
A STUDY OF AIR POllUTION IN THE INTERSTATE REGION OF
lEWISTON, IDAHO, AND ClARKSTON, WASHINGTON.
This joint study of air pollution in the Lewiston-Clarkston area was conducted by State
and local agencies and the Public Health Service during the winter of 1961-l962.l! The purpose of
the study was to determine the nature and extent of air pollution in the two communities, and to
assemble data and information needed as a basis for remedial action. The study included the
followfnq activities:
1. Analysis of past and current data on weteoroloay.
2. An emission inventory.
3. Measurement of atmospheric pollutants.
4. Measurement of visibility.
5. Assessment of ambient odors.
6. neasurement of materials deterioration.
7. Interview of local physicians concerninQ health effects.
8. A survey of public opinion.
r1eteoroloqical studies included a revie~1 of past climatoloqical and meteorological data, and
observations of wind speed, wind direction, temperature, and relative humidity at a station in the
valley to supplement concurrent data collected at the Lewiston airport. The cities frequently
experience poor atmospheric ventilation because of low wind speed and low-level inversions. The
predominant wind direction is from the east, particularly at niqht. Stationary high-pressure
systems conducive to air pollution and lastinq several days can be expected twice yearly. Low-
level inversions occur most frequently in the fall, when they may be expected to occur about 50
percent of the time. f1eteoroloqical measurements durinq the samplina period showed wind speeds
hiqher 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 samplinq was done, and all estimates were
based on information from the literature and other sources.
The major contributor of hydroqen sulfide and other malodorous orqanic qases is the kraft pulp
mill. In addition, the pulp mill contributes about 77 percent of the estimated qaseous 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. (About this same amount is emitted by the
paper mill and other Potlatch operations.) The latter is believed to have a significant effect
7
-------
8
on the humidity in the valley under certain meteorological conditions. 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.
The amounts of emissions from other industrial operations are relatively small. Home heating
is the larqest source of sulfur oxides, and 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 odors produced by burning qarbage and refuse
cause 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 at a control station in Moscow, Idaho.
Concentrations of hydrogen sulfide were highest in November and February. which were periods
of more frequent inversions. Hydrogen sulfide 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 a.m. and 12 noon in the Lewiston commercial area. The time
difference results from the unique topoqraphy of the study area. Two sta~nant weather episodes
were observed in which hydrogen sulfide concentrations exceeded 10 parts per billion.
Atmospheric sulfur dioxide concentrations were highest in January (ranqe
average 4.7 ppb) durinq the coldest period, indicating fuel burning for space
primary source. Maximum daily concentrations occurred at 9 a.m., at the time
Atmospheric contamination by sulfur dioxide is not currently a problem in the
Clarkston area.
o to 25 ppb,
heating as the
of inversion breakup.
Lewiston-
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.
Paint and silver specimens were exposed to measure deterioration caused by hydroqen sulfide
and other sulfide compounds. Silver plates were also exposed at a control station in Moscow,
Idaho. Data from these tests showed neglioible silver tarnishinq in r~oscow. Silver plates
exposed in the valley were tarnished more than those exposed in the upland sites. The relative
severity of tarnishinq, as an indicator of sulfide qases in the air, is greater in Lewiston than
in Clarkston. The results obtained from exposed paint samples were inconclusive.
Odor surveys made in November and in April show that pulp mill odors represent the largest
single odor category; the odors affect Lewiston most in November and Clarkston most in April.
-------
r,
7
COMMUNITY PERCEPTION OF AIR QUALITY-AN OPINION SURVEY IN CLARKSTON, WASHINGTON
A survey of public opinion concerninq air pollution in Clarkston, Wash., was conducted by
personnel of the Public Health Service, the Washinqton State Department of Health, and the Research
Trianqle Institute, Durham, t1. C.Y By use of statistical procedures a sample of 104 households
was selected for interview. Interviews were conducted durinq the period May 20 throuah 25, 1962:
the head of the household or spouse was interviewed in each case. Almost 80 percent of the
persons intervie~led stated that Clarkston has an air pollution problem and almost two-thirds
stated that they were bothered by it in some deqree. nore than 90 percent associated air pollution
with frequent bad smells in the air, and almost 75 percent associated air pollution with frequent
haze or foa. More than 70 percent of the 104 persons interviewed, or more than 90 percent of those
who recognized an air pollution problem, mentioned the pulp mill first amonq the major sources of
air pollution in the area.
AN AIR QUALITY STUDY IN THE VICINITY OF lEWISTON, IDAHO,
AND CLARKSTON, WASHINGTON
The Division of Industrial Research, Hashinqton State University, conducted a l3-month
study of air quality in the Lewiston-Clarkston area at the request and with the financial
support of Potlatch Forests, Inc., beqinninq in December, 1961.11 T~IO-hour interval samplinq
for soilinq index and hydroaen sulfide was accomplished at three sites, 24-hour samplino for
suspended particulates at two sites, and 30-day dustfall and sulfation rate samples at 14 sites
in the survey area. I'find speed, wind direction, and air temperature at the surface were
recorded at three sites, and air temperatures at 20, 40, 60, 80, and 100 feet elevation in the
lower atmosphere were recorded at one site.
The concentration of hydroqen sulfide was measured by the darkeninq of paper tape impreqnated
with lead acetate. Data reported for the study indicate that hydroaen sulfide concentrations
averaqed about 10 to 15 parts per billion parts of air at the Clarkston samplinq site durinq
the fTlonths of October, tlovember, December, ,January, and February. The months with hiqhest
concentrations reported for the Le~tiston samplino site, t:ovefTIber and December, averaqed about
7 to 9 parts hydroqen sulfide per billion parts of air. The concentrations reported for the
tJorth Lewiston site, the Idaho State Hiqhway qaraqe, for October, tlovember. and December (the
hi qhes t r;Jonths) averaged about 25 to 30 pa rts hydrooen sulfide per bi 11 ion pa rts of ai r.
Averaqe values for soilinq index for Clarkston, Lewiston, and North Lewiston were reported
as 0.76, 0.64, and 0.42 COH per 1,000 lineal feet respectively.
Dustfall ranqed from 7.4 to 315 tons per square mile per month above backqround values.
Averaqe values of 26.41 and 68.78 tons per square mile per month were reported for sodium and
sulfate respectively at the Idaho State Hiohway oaraoe site in North Le~liston. t.1uch lower values
for these materials were found in samnles frofTI other sites. Heavy dustfall in downtown
commercial areas of Lewiston and Clarkston was reported to contain hiqh percentaoes of self-
qenerated materials such as incompletely burned carbonaceous material not related to a specific
industrial source.
-------
10
The rerort concluded that substantially hiqher levels of Dollutants were obtained durinq the
heatinG season, indicatinG that emissions resultinq from combustion of fuels for srace heatinq
contributed siqnificantly to overall air pollution. Winter meteoroloqical staqnation also
contributed siqnificantly to hiqher winter-time pollutant levels.
-------
SECTION IV-INVENTORY OF COMMUNITY ATMOSPHERIC EMISSIONS
Inventories of emissions to the atmosphere in the Lewiston-Clarkston area conducted in
1961-1962 have been reported.~ An inventory wa~ conducted in the fall of 1966 to determine
whether substantial changes have occurred since the earlier surveys. The 1966 inventory
differs in some respects from the earlier inventories; the differences result in part from
changes in fuel use patterns, increased motor vehicle use, differing sources of information,
and use of revised pollutant emission factors for some processes or pollutant sources. In
general, emissions from the community have not changed markedly since the 1961-1962 inventories.
INDUSTRIAL PROCESS EMISSIONS EXCLUDING POTlATCH FORESTS, INe.
The main industrial operations that could contribute to air pollution in the Lewiston-
Clarkston area, in addition to operations of Potlatch Forests, Inc., include three lumber
mills, three meat packing operations, two frozen food packing plants, two asphalt road mix
plants, a number of grain mills and elevators, and four concrete mixing plants. Industrial
operations with little or no atmospheric pollution potential include bakeries, ammunition
manufacturing plants, machine shops, and bottling plants. The following discussions are based
upon the emissions inventory conducted during 1966.
lumbering Operations
The three lumber mills in this area all use teepee-type wood waste burners. The two
burners observed in Clarkston and the one in .Lewiston were not operating under good combustion
conditions. Large quantities of air entering through cracks, open doors, and air ports rapidly
cooled the fire and prevented adequate burning of the wood waste material. A continual
grayish smoke plume was visible at each teepee burner.
In addition to the three lumbering operations in Lewiston and Clarkston, there is a large
lumber mill in Clearwater, Idaho. This plant, located about 8 miles east of Lewiston on the
Clearwater River also burns large quantities of scrap wood in a teepee burner. Under certain
meteorological conditions, the smoke from this burner drifts down valley toward the Lewiston-
Clarkston area.
Estimates of the atmospheric emissions from the three burners i~ the Lewiston-C1arkston
area were based on estimates of the amount of wood burned. It was assumed that 50 percent of
the raw wood is reduced to scrap in the form of bark, slabs, and sawdust,~ and that
40 percent of this scrap material, which weighs about 2.25 pounds per board foot, is burned
in the teepee burners. These burners usually operate 5 days per week and are estimated to
burn a total of about 68 tons of wood per operating day. Most of this burning takes place
during the daylight hours, although the fires smoulder during the night.
11
-------
12
Calculated atmospheric emissions from teepee burners based on estimates of the amounts of
wood burned and published emission factors~ are shown in Table I.
Asphalt Mix Plants
Two asphalt road mix plants operate in the area very intermittently, dependinq on
demand for asphalt mix and on the weather. These plants contribute large amounts of fine
dust to the atmosphere when operating even though they are equipped with qas-cleaning devices.
To calculate emissions from these plants, production rates and published emission factorsZ!
\~ere used. It was estimated that the gas-cleaning equipment collects 75 percent of the
particulate matter generated. Calculated emissions are shown in Table I.
TAl3LE
ESTIMATED ATMOSPHERIC EMISSIONS
EXCLUDING POTLATCH
I
FROM INDUSTRIAL OPERATIONS
FORESTS, I NC.
Source
Avg Process
Weight
tons/day
Particulate
Emissions, lb/day
Carbon b
Monoxide Hydrocarbons
AldehydesC
1.
Clarkston, Wash.
Guy l3ennett Lumber Co.
(teepee burner)
J. G. Lumber Co.
(teepee burner)
36a
360
720
720
71
18a
180
360
360
35
United Paving Co.
200
150
Sub Total, \.Jashington
254
690
1080
1080
106
2.
Lewiston, Idaho
R. W. Lumber Co.
(teepee burner)
Asphalt & Paving Co.
14a
140
280
280
24
Grain-Handling Operations
Concrete f1i xi nq
50
103
40
230
600
12
Sub Tota 1, Idaho
397
792
280
280
24
GRAND TOTAL
651
1482
1360
1360
130
aQuantity burned.
b
Exrressed as methane.
cExpressed as formaldehyde.
Food Processing Plants
The meat packinq plants in this area use natural gas for process heatinq and do not
normally cause any visible emissions other than steam plumes. They are, however, intermittent
sources of localized odor. The frozen food plants also utilize natural gas for process
-------
13
heating and generally emit only
Calculated emissions from these
in Table 1.
water vapor and gas combustion products to the atmosphere.
sources are insignificant; no emissions are listed for them
Concrete Mixing and Grain Handling
The concrete batch plants and the grain-handlinq operations both emit dust to the
atmosphere. These emissions are decreased by the use of wet mixinq techniques at the
concrete plants and cyclone collectors at the qrain mills. A localized dust problem is,
however, still caused by these intermittent operations.
Production or process weights were not obtained'for concrete-mixing and qrain-
handling operations during the 1966 inventory. In the absence of more recent data, values
reported by Tuttle and Adams were used.~ For concrete plants an emission factor of
0.1 pound of dust per cubic yard of concrete mixed was used to calculate emissions, and for
qrain handlinq an emission factor of 0.3 percent by weight of the grain handled was used.
Because data for individual plants were not available, only total emissions for these
operations are shown in Table I.
fUEL USAGE
Non-Industrial fuels
Atmospheric emissions result from the combustion of fuels used for space heating.
Fuel consumption varies inversely with the ambient temperature, and is hiqhest when
temperatures are lowest. Distillate fuel oils and natural gas are the two main types of
fuel used for heating purposes in this area. They are currently used in approximateiy
equal amounts. Natural gas consumption is risinq much more rapidly than fuel oil
consumption, however, and should become the predominant fuel within a few years. Both gas
and the light fuel oils burn fairly cleanly in modern, properly adjusted furnaces and are
not major sources of air pollution.
A survey of fuel consumption in the Lewiston-Clarkston area in October 1966
showed that approximately 4.4 million qallons of number 1 and 2 fuel oil is sold annually
in the area for non-industrial heating purposes. About 63 percent of this fuel is burned
in the Lewiston area. Average sulfur content of this fuel, as reported by the U. S. Bureau
of rlines, is 0.31 percent by vleight. 'i}j
Total annual natural gas consumption by approximately 3,250 customers amounts to
5,730,752 therms or 536 million cubic feet excluding that used by Potlatch Forests, Inc.
Approximately 82 percent of this fuel is used for non-industrial, i.e. commercial and
domestic heating purposes. This gas contains 0.005 grain df sulfur per cubic foot. Some
1 i quefi ed propane is a 1 so burned as fue 1 j hm-Iever, it represents on ly a small percentaqe
of the total fuel usage.
Approximately 200,000
non-industrial consumers.
fJormal School in Lewiston
gallons of residual fuel oil is also burned annually by
This fuel contains about 1.2 percent sulfur. The Lewis-Clark
is the primary consumer of this fuel.
-------
14
Approximately 6 percent of the heatinq-fuel requirements in this are are
supplied by coal. During 1965 about 3,600 tons was consumed; about 65 percent of this
coal was consumed in the Lewiston area. In addition to domestic consumers, a small number
of public buildings burn coal for heating purposes. Coal used in the area is mined in
Utah and has an average sulfur content of 0.6 percent and an ash content of about
6.5 percent.
Wood, largely in the form of "Presto Loqs," is also used for heatinq, mainly as' a
supplement to other heating fuels. About 10,000 tons of wood was burned in 1965.
Average estimated atmospheric emissions resulting from non-industrial fuel usage
are shown in Table II. Total fuel consumption was obtained from the various fuel suppliers
in Lewiston and Clarkston, and published emission factors were used to calculate total
emissions.Z! An average heating season of 205 days was used to relate annual fuel use to
emissions during an average heating day.
TABLE II
ESTHIATED AVERAGE ATr10SPHERIC EtHSSIONS RESULTING FROt~ THE
COMBUSTION OF FUELS FOR NON-INDUSTRIAL HEATINGa
(pounds per day)
Carbon Sulfurb Nitrogee Hydro- d Organif
Type of Fue 1 Solids r.1onox i de Oxides Oxides carbons Aldehydese Ammonia Acids
Natural Gas, 3 40 3 240 120
430 million ft /yr
Light Fuel Oils, 260 45 925 1550 45 45 22 420
4.4 million gal/yr
Residual Fuel Oil, 12 183 80 3 2 12
0.2 million ga1/yr
Coal, 3600 tons/yr 1150 90 420 140 175
Wood, 10,000 tons/yr 150 245 8 60 490 50 20
TOTAL 1612 382 1539 2070 713 98 24 472
aBased on a 205-day heating season. bExpressed as sulfur dioxide. cExpressed as nitrogen dioxide.
dExpressed as methane. "Expressed as formaldehyde. fExpressed as acetic acid.
Industrial Fuels
Most of the industries in the Lewiston-Clarkston area burn natural gas for process
heating purposes. Industrial natural gas consumption, not including Potlatch Forests, Inc.,
was about 106 million cubic feet during 1965. An estimated 100,000 gallons of residual fuel
oil was also consumed for process and industrial space-heatinq needs.
Estimated atmospheric emissions of the more significant pollutants from industrial
fuel consumption are shown in Table III.
-------
TABLE I II
E&TIMATED ATMOSPHERIC EMISSIONS
FROM THE COMBUSTION OF FUEL FOR INDUSTRIAL PURPOSES
EXCLUDING EMISSIONS FROM POTLATCH FORESTS, INC.
(pounds per day)
Solids
Sulfur
Oxides
Nitrogen
Oxides
Natura 1 Gas,
106 million ft3/yr
7
80
Residual Fuel Oil
0.1 million gal/yr
TOTAL
5
12
95
95
32
112
REFUSE DISPOSAL
The domestic and commercial burning of refuse is a chronic source of localized air
pollution. Many commercial establishments, especially food markets, burn large quantities
of cardboard and wooden boxes. Many homeowners burn refuse in their backyards. This type
of burning frequently occurs under extremely poor combustion conditions and results in the
intermittent release of dense smoke and other atmospheric pollutants.
Mandatory refuse collection exists in the incorporated areas of both Lewiston and
Clarkston. Voluntary collection service is available in the Lewiston Orchards area.
Clarkston Heights has no mandatory refuse collection service, and many residents burn their
own refuse or haul it a distance of 2 or 3 .miles to the local dump area. The Lewiston
sanitary landfill, located near the airport, rarely burns. At the Clarkston dump site,
however, brush is separated from the balance. of the refuse and periodically burned. In
addition, other fires caused by hot coals or other burning material dumped by individuals
frequently occur.
No accurate estimate of the amount of refuse burned daily exists. However. based on
discussions with local officials concerning the amount of refuse collected for disposal
other than by burning, and using an estimate of 1400 pounds of refuse per capita per year.
approximately 30 tons of refuse are burned per day about 300 days a year in this area.
Table IV lists calculated atmospheric emissions created by open burning of refuse in the
Lewiston-Clarkston area. Emission factors were obtained from the literature.7,9/
Lewiston and Clarkston each has its own municipal primary sewage treatment plant.
Neither of these plants causes any significant air pollution during normal operation.
Localized odor problems may result during plant upsets.
VEHICULAR EMISSIONS
There are presently about 16,500 motor vehicles in the Lewiston-Clarkston area. These
vehicles burn an estimated 12 million gallons of gasoline each year. In addition, trucks
-------
16
TABLE IV
ESTIMATED ATMOSPHERIC EMISSION FROM.BURNING REFUSE
Amount Emissions, lb/day O' b
Burned, Carbon Hydrocarbonsa rgam c
District tons/yr Solids Monoxide Acids
lewiston 1950 115 540 202 100
lewiston Orchards 3500 204 965 362 181
Clarkston (backyard) 1200 70 330 124 62
Clarkston (dump) 800 49 220 82 42
Clarkston Heights 1250 72 345 130 65
TOTAL 8700 510 2400 900 450
aExpressed as methane.
bExpressed as acetic acid.
burn about 87,000 gallons of diesel fuel each year. Tail pipe and crankcase b10wby emissions
are the major vehicular sources of atmospheric pollution.
Evaporation of gasoline both from automobile gas tanks and c~rburetors, and from
gaso1ine.station tank-filling operations also add to the total hydrocarbon emissions. The
increased use of engine blowby devices and exhaust control systems on 1968 model cars will
decrease the emissions from automotive vehicles in the future.
Table V presents the estimated atmospheric emissions currently resulting from vehicular
fuel consumption and service station tank-filing operations.
SUMMARY OF COMMUNITY EMISSIONS (EXCLUDING POTLATCH FORESTS, INC.)
A summary of community-wide calculated pollutant emissions by source category in each
State appears in Table VI.
TABLE V
ESTIMATED ATMOSPHERIC EMISSIONS FROM MOTOR VEHICLES
(Pounds per day)
Carbon Sulfura Nitrogeg Hydro- c d Organi!!
Solids t1onox i de Oxides Oxides Carbons Aldehydes Ammonia Acids
Gasoline,
12 million gal/yr 330 99,000 230 3,300 17,830 165 65 130
Diesel fuel,
87,000 gal/yr 25 12 10 55 45 5 7
TOTAL 355 99,012 240 3,355 17,875 170 65 137
aExpressed as sulfur dioxide. bExpressed as nitrogen dioxide. cExpressed as methane.
dExpressed as formaldehyde. eExpressed as acetic acid. fInclude evaporative losses from
tanks. and filling operations.
-------
TABLE VI
EMISSIONS INVENTORY SUMMARY TABLE
LEWISTON-CLARKSTON ABATEMENT ACTIVITY, 1966
(pounds per day)
Process Emissions Industrial Fuel Non-Industrial Refuse Grand Total
ExCl. PFI Exc1. PFI Fuel Disposal Vehicular Exc1. PFI
Pollutant Idaho Wash. Total Idaho Wash. Total Idaho Wash. Total Idaho Wash. Total Idaho Wash. Total Idaho Wash. Total
Solids 792 690 1482 10 2 12 1020 592 1612 322 188 510 245 110 355 2,389 1,582 3,971
Carbon 280 1080 1360 - ., - 242 140 382 1510 890 ~400 68,400 30,610 99,012 70,432 32,722 103,154
Monoxide
Sulfur a - - - 86 9 -95 1018 521 1539 - - - 165 75 240 1269 605 1,874
Oxides
Nitrogenb - - - 101 11 112 1319 751 2070 - - - 2,310 1 ,p45 3,355 3,730 1,807 5,537
Oxides
c 280.1080 1360 450 263 713 568 332 900 12,300 5,575 17,$75 13,598 7,250 20,848
Hydrocarbons - - -
A1dehydesd 24 106 130 - - - 60 38 98 - - - 117 53 170 201 197 398
Ammonia - - - - - - 15 9 24 - - - 45 20 65 60 29 89
Organice - - - - - - 308 164 472 284 166 450 95 42 137 687 372 1,059
Acids
~xpressed as sulfur dioxide
EExpressed as acetic acid.
trxpressed as nitrogen dioxide.
~xpressed as methane.
ctxpressed as formaldehyde.
""-I
-------
S ECTION V-AT MOS PH ERIC E-MISS IONS F ROM POTLATCH FOR ESTS, I NL ;
KRAFT PULP MILL AND LUMBER MILL
Potlatch Forests, Inc., supplied to the Public Health Service, through the Idaho
Department of Health, detailed data regarding emissions of atmospheric pollutants from its
Lewiston plants. In transmitting the data Potlatch Forests, Inc., stated, "These are a
sincere effort on our part to give the best information we have available; however. many of
these tests are the result of only one or two testings and may require additional information
in the future." Implicit in this statement is recognition of the variability of emissions
from individual sources in a kraft pulp mill. Emissions can, and do, vary from hour to hour,
and from day to day. They vary with production rate, with conditions of operation, and with
the adequacy of performance of control facilities. Precise emissions data usually require
repeated tests for various conditions of operation and over considerable periods of time.
The data provided by Potlatch Forests, Inc., have been used in discussions of emissions
in this report. It is recognized that emission values somewhat different from those
reported might be yielded by repeated testing. This reservation is not intended as
criticism of the information supplied by Potlatch Forests, Inc.; to the contrary, the
Company is commended for having developed at our request such a large array of data in so
short a period of time.
REVIEW OF KRAFT PULP PROCESS
The kraft pulp industry has enjoyed spectacular growth during the past 25 years, and
annual production is currently about 23,000,000 tons. The kraft pulping process utilizes
an alkaline solution of caustic soda (sodium hydroxide) and sodium sulfide to separate
cellulose fibers from lignin and other non-cellulose portions of wood. The cellulose fiber,
or pulp, is washed and used to manufacture paper. The non-fiber portion of the wood is
burned to recover chemicals and to provide process heat.
To separate cellulose from
vessels called digesters where
called white liquor.
lignin, wood in the form of small chips is fed into large
it is cooked for 2-1/2 to 3 hours in an alkaline solution
The white liquor is composed largely of sodium hydroxide and sodium sulfide. Steam is
injected into the digesters until a pressure of 110 psi is attained. Gases generated by the
chemical process are vented periodically during the cooking period.
After completion of the cooking period, a digester charge is blown into a receiver
called a blow tank. During this sudden decrease in pressure, the softened wood chips
19
-------
20
disintegrate, furthering the separation of the cellulose pulp fibers from the lignin. The
pulp is filtered and washed free of spent cooking chemicals. The spent cooking liquor and
wash water, called black liquor, is concentrated in a series of evaporators.
The concentrated black liquor is sprayed into recovery furnaces, and the lignin and
other combustible materials in the liquor are burned to generate process steam. Chemical
recovery js accomplished by drawing off the molten mixture of sodium compounds from the
furnaces. This melt is dissolved in water to form green liquor, which in turn is reacted
with lime to convert sodium carbonate to sodium hydroxide. The sludge, or lime mud,
produc~d in this reaction is settled out and returned to a lime kiln. The resulting clear
solution, called white liquor, is reused as cooking liquor in the digesters. A lime kiln
is used to calcine the lime mud to calcium oxide for reuse in converting green liquor to
white liquor.
A block diagram of the pulping and chemical recovery process is shown in Figure 2.
DESCRIPTION OF POTLATCH FORESTS, INC.,
PULP Mill PROCESSES AND THEIR EMISSIONS
The Potlatch Forests, Inc., pulp mill produces an average of 755 tons of air-dried pulp
per day, although maximum daily production rates have ,been as high as 825 tons.
Digestion and Blow System
The pulp mill contains nine batch digesters with a total capacity of 30,800 cubic
feet. In addition, there are two continuous digesters. The wood chips are 42 percent
pine and 41 percent fir, with the balance comprised of cedar, larch, and spruce. Cooking
with steam and white liquor at a temperature of 3500F at 110 psi dissolves the lignin and
other similar material in the wood, freeing the cellulose fibers.
During the cooking period, gases are periodically released from the digester. These
relief gases are passed through a cyclone separator and a condenser. The condensate and
uncondensed gases are passed to an accumulator tank where they are sprayed with a hypo-
chlorite solution from the pulp-bleaching process. The non-condensable gases are released
to the atmosphere.
When a cooking cycle is completed, the digester contents are suddenly released into a
blow tank. This sudden decrease in pressure and violent agitation aids in separating the
pulp from the lignin. Gases released in the blowing operation are vented through a
condenser to the deodorizer tank where they are sprayed with hypochlorite solution; the
remaining non-condensable gases are released to the atmosphere.
Atmospheric emissions from the digester and blow tank systems occur intermittently.
Under normal operating conditions, 72 batches of wood chips are cooked and blown each day,
-------
21
U.C.G.-UNCONDENSED GASES
TO
ATMOSPHERE
U.c.G.
CONDENSER
STEAM
PULP, U.c.G.
WEAK BLACK LIQUOR
P~LP TO E:~ ,WATER
PAPER I
MACHINES BLACK LIQUOR (15% SOLIDS)
I
U.c.G.
LIQUID
MULTIPLE EFFECT
EVAPORATORS
U.c.G.
TO
ATMOSPHERE
STEAM
8. U.c.G.
BLACK LIQUOR (50% SOLIDS)
t.
CONDENSER
DIRECT CONTACT
EVAPORATOR
SALT BLACK LIQUOR VENTURI
CAKE (65"% SOLIDS) r SCRUBBER
~~~~6 I FLUE BLACK LIQUOR (60% SOLIDS)
4 t GAS t, SALT CAKE
RECOVERY RECOVERY H2S04,NaHS04
FLUE
GAS FURNACE FURNACE
ELECTROSTATIC
PRECIPITATOR
TO
ATMOSPHERE
FLUE GAS
FLUE GAS
TO
ATMOSPHERE
I SMELT TANKS I ( WATER
GASES, VAPORS
&. PARTICULATES
..
TO
ATMOSPHERE
WATER
NATURAL GAS
TO
ATMOSPHERE
Figure 2.
Schematic diagram of Potlatch Forests, Inc.,
kraft pulping process.
-------
22
an average of 3 per hour, or one every 20 minuts.
operation approach those from a continuous system.
Thus, emissions from this batch
According to data received from Potlatch Forests, Inc., there are no detectable atmos-
pheric emissions, except water vapor, from this part of the process. This would indicate
a 100 percent efficient gas scrubbing system. With9ut a control system, emissions in the
order of 0.45 pound of hydrogen sulfide, 2.5 pounds of methyl mercaptan, and 1.4 pounds of
dimethyl sulfide per ton of pulp could be expected.l2I Such emissions would amount to
2,100 pounds of sulfur per day for a 755-ton-per-day production rate.
Multiple-Effect Evaporators
The digested wood pulp is filtered and washed with water to recover chemicals used
in the digestion process. This washing process yields a liquid called black liquor. Black
liquor is concentrated by passage through four sets of countercurrent multiple-effect
evaporators. The liquor enters the evaporators at a concentration of about 15 percent
solids and leaves at a concentration of 50 percent.
Because of the high concentration of sulfurous compounds in the black liquor entering the
evaporators, large quantities of odorous gases are given off in the evaporation process. Particulate
emissions are, however, not produced by the evaporators. Emissions from the multiple-effect
evaporators, as reported by Potlatch Forests, Inc., are shown in Table VII.
TABLE VII
ATMOSPHERIC EMISSIONS FROM MULTIPLE-EFFECT EVAPORATORSa
(pounds per day)
Sulfur Hydrogen Alkyl Alkyl Water
Evaporator Dioxide Sulfide Mercaptans Sulfide Disulfide Vapor
Set 1 0 50.1 11.2 20.6 1.1 135,000
Set 2 and 3 0 107 555 169 6.0 92,000
Set 4 0 0.7 0.2 1.6 0.9 6,520
TOTAL 0 157.8 566.4 191 .2 8.0 233,520
a. Sulfur-containing compounds are expressed as pounds of sulfur.
Direcl-Contacl Evaporators and Recovery Furnaces
After leaving the multiple-effect evaporators, the black liquor is split into
three streams. Two of these streams enter direct-contact disc-type evaporators while the
third stream enters a recovery furnace flue gas scrubbing system. In all three cases contact
with hot flue gases further concentrates the black liquor to a concentration of about
65 percent solids. Contact with the hot flue gases releases odorous sulfurous gases that
are carried by the flue gases into the atmosphere.
-------
23
The concentrated black liquor and make-up sodium sulfate is sprayed into the
recovery furnaces where organic materials in the black liquor are burned. The heat evolved
is used to qenerate steam for various plant processes. Three recovery furnaces are used at
Potlatch Forests, Inc. Make-up sodium sulfate is added at the rate of 98 pounds per ton of
air-dried pulp, which is equivalent to 16,700 pounds of sulfur per day, based on a daily
. . d'p1Jde .
productlon rate of 755 tons. Spent llquor from the chlorlnllplant, composed of sulfurlc
acid and sodium bisulfate, is used along with salt cake as part of the chemical make-up.
This make-up is equivalent to 8.6 pounds of sulfur per ton of pulp produced.
By limiting the amount of air entering the (irst combustion zone of the recovery
furnaces, a reducing atmosphere is maintained and a portion of the sodium sulfate (Na2S04)
is reduced to sodium sulfide (Na2S), In addition, sodium carbonate (Na2C03) is formed by
the burning of organic sodium compounds. A molten residue of sodium sulfide and sodium
carbonate thus formed is tapped from the furnaces and dissolved in water to form green
liquor.
Hot flue gases from the furnaces contain gaseous sulfur compounds, solid particles,
water vapor, carbon dioxide, nitrogen, and at times some oxygen. The hot flue gases from
two furnaces pass through direct-contact disc evaporators that serve as the final evapor-
ation stage for black liquor, then pass through a single electrostatic precipitator to the
atmosphere. The present electrostatic precipitator was installed to replace two less-
efficient units that were in use at the time of the 1961-62 survey. The flue gas from the
third furnace passes through a venturi scrubber that serves as a direct-contact evaporator
by using black liquor as the scrubbing medium. Solid material collected in the electro-
static precipitator is returned to the direct-contact evaporators by a stream of black
liquor.
The design rate for furnaces one and two, which are equipped with the electrostatic
precipitator, is 1,575,000 pounds of solids per day. Furnace number three, equipped with
a vent~ri scrubber, is designed to handle 900,000 pounds of solids per day. The electro-
static precipitator is reported by Potlatch Forests, Inc., to be 95 percent efficient in
collecting particulate; the collection efficiency of the venturi scrubber is reported to be
74.2 percent. Particulate emissions from the recovery furnaces represent a major source of
atmospheric pollution from this plant.
Malodors result from the burning of black liquor, especially when an excess of
oxygen is not maintained in the secondary combustion zones of the furnaces, and by passaqe
of the furnace flue gases through the direct-contact eva~orators. Secondary combustion air
injected into the upper portion of the recovery furnaces decreases the amount of odorous
sulfur gases emitted. Potlatch Forests, Inc., reported that the oxyqen content of the flue
gas varies from 0 to 3 percent by volume, which would indicate that excessive amounts of
odorous compounds could be released during periods of insufficient air supply to the furnace.
Table VIII summarizes atmospheric emissions from the three recovery furnaces as
reported by Potlatch Forests, Inc.
-------
24
TABLE VIII
ATr10SPHERIC EMISSIONS FROM POTLATCH FORESTS, INC. RECOVERY FURNACESa
(pounds per day)
Sulfur Hydrogen Alkyl A 1 ky 1 Water
Furnace Dioxide Sulfide t~ercaptan Sulfide Disulfide Particulate Vapor
1 and 2 2.3 806 93.6 0 61.2 5,140 1,742,000
3 8.4 627 981 7.3 5.7 17,700 1 ,806,000
TOTAL 10.7 1,433 1,074.6 7.3 66.9 22,840 3,548,000
aSulfur-containing gases are expressed as pounds of sulfur.
Calculations based on other data provided by Potlatch Forests, Inc., show that total
hydrogen sulfide emissions may reach a rate of 5,400 pounds per day from all three recovery
furnaces. This rate of hydrogen sulfide emission from recovery furnaces of a mill of this
size having no facility for controlling hydrogen sulfide emissions from the furnaces is not
ex traord i na ry.
Smelt Tank, Causticizing Tank, and lime Kiln
The molten chemical residue tapped from the furnace bottom is water quenched in
smelt tanks. This sudden cooling of the molten chemicals causes the material to shatter and
results in the release of solid particles and some sulfurous gases. Relief gases from the
three smelt tanks pass through a demister where liquid droplets are removed before the gases
are discharged to the atmosphere.
Total vent gas from the smelt tanks is approximately 6,800 cfm at a temperature of
1800 to 2400F. Reported atmospheric emissions are shown in Table IX.
Green liquor goes from the smelt tanks to a clarifier, or settling tank, where
solids are removed. The green liquor then goes to a slaking tank where lime (CaO) is added,
and to a causticizer where the reaction between lime, water, and sodium carbonate occurs
to form sodium hydroxide. The reactions that result in a solution called white liquor are
CaO + H20 ~ Ca (OH)2
Na2 C03 + Ca (OH)2 ~ Ca C03 + 2 NaOH
There are six causticizers at the Potlatch Forests, Inc., mill; however, these
chambers are not significant sources of atmospheric pollution.
The lime mud, largely calcium carbonate that settles out in the causticizers and
subsequent clarifiers, is returned to the lime kiln after washing and filtering. A single
large, gas-fired, rotary lime kiln calcines the lime to calcium oxide (CaO). This kiln
processes about 10 tons of lime per hour. Hot gases composed largely of carbon dioxide,
-------
25
water vapor, sulfurous compounds, oxygen, and nitrogen pass from this kiln through a
venturi water spray scrubber that removes particulate matter. This high-energy scrubber
utilizes a pressure drop of about 16 inches of water and has a particulate collection
efficiency of about 97.6 percent. This lime kiln venturi scrubber combination was
installed to replace three less efficient units that were in use at the time of the
1961-62 survey. Atmospheric emissions from the lime kiln scrubber, as reported by Potlatch
Forests, Inc., are shown in Table IX.
ATMOSPHERIC EMISSIONS
TAGLE IX
FROM POTLATCH FORESTS,
(pounds per day) .
INC., SMELT TANKS AND LIME KILNa
Sulfur Hydrogen A 1 ky 1 Alkyl Parti- Wa ter
Dioxide Sulfide Mercaptans Su lfi de Disulfide cu 1 ate Vapor
Smelt Tanks 1.1 0 2.6 0 2.8 410 106,400
Lime Kiln 1.3 72.4 18.1 161.0 87.6 760 1,070,000
TOTAL 2.4 72.4 20.7 161.0 90.4 1170 1,176,400
aA11 sulfur-containing gases are expressed as pounds of sulfur.
Steam Boiler Plants
Two boiler plants provide additional process steam for pulp mill operations at
Potlatch Forests, Inc. These units normally burn natural gas and are not a major source of
atmospheric pollution. During the winter months, however, additional heating requirements are
supplied by residual fuel oil. This fuel contains between 1.1 and 1.45 percent sulfur, end
for an average daily rate of 9,800 gallons, approximately 1,950 pounds of sulfur dioxide would
be emitted per day during periods of its use.
The lumber division of Potlatch Forests, 'Inc., utilizes four boilers rated at
1,100 horsepower each. These boilers are fired with natural gas and scrap wood material.
Particulate emissions from these boilers varies with the type of fuel used and the firing
rates. Data reported by Potlatch Forests, Inc., show a daily emission of 1,080 pounds of
solids resulting from the production of 20,000 tons of steam.
Other Sources of Atmospheric Pollution
Other relatively minor sources of pollution include paper driers and leaks in process
equipment. A large silo-type wood waste burner is also us~d occasionally; it causes a local
smoke problem when in operation. When operated properly, these processes are not a major
source of air pollution.
SUMMARY OF PULP MilL EMISSIONS
Table X presents a summary of atmospheric emission data reported by Potlatch Forests, Inc.
Emissions from the various pulp mill sources vary greatly and depend on the prevailing
-------
26
operating conditions. Average emissions are difficult to estimate precisely without a great
deal of effort and cost.
TABLE X
SUM~~RY OF ATMOSPHERIC EMISSIONS FROM
POTLATCH FORESTS, INC., PULP MILL AND POWER BOILERS
(pounds per day)a
Sulfur Hydrogen A 1 ky 1 Alkyl Water
Source Dioxide Su lfi de Mercaptans Sulfide Disulfide Particulates Vapor
Multiple Effect
Evaporators 0 158 566 191 8 233,520
Recovery Furnaces 11 1433 1075 7 67 22,840 3,548,000
Smelt Tanks 0 3 0 3 410 106,400
Lime Kilns 1 72 18 161 88 760 1,070,000
Power Boil ers 31b 20 1,080 10,349,000
TOTAL 44b 1663 1662 359 186 25,090 15,3D6,920
aA11 sulfur-containing gases are expressed as sulfur.
bReported emissions for summer months; emissions during the
winter can be as high as 1,950 pounds per day.
-------
SECTION VI-DISCUSSION OF CONTROL TECHNOLOGY
Potlatch Forests, Inc., has reported that sin€e the survey of 1961-1962 several changes in
operation or e~uipment that may affect emission of air pollutants have been made. These include:
1. Oxidation of weak black liquor has been discontinued because of operatino problems. This
I'IOU 1 d tend to increase emi s s ions of odorous oases from the recovery furnace di rect-contact evaporator
sys tem.
2. Use of lime kilns numbers 1 and 2 has been discontinued: kiln number 3 has been extended, and a
new scrubber has been installed. Emissions from lime burning should be substantially lower than
the 1961 level s.
3. The electrostatic precipitators of recovery furnaces number 1 and 2 have been replaced with a
sinqle electrostatic precipitator of hinher collection efficiency. This installation is reported
to have substantially reduced emission of particulates from these two furnaces.
4. Steam atomizinq nozzles were installed in the venturi evaporator on the number 3 recovery
furnace in an effort to increase its efficiency in collection of particulates from the furnace
flue qases; however, satisfactory collection efficiency has not been achieved.
5. The chlorine dioxide tower vent scrubber was replaced with a lamer unit. Increased efficiency
in the collection of chlorine dioxide is reported.
6. The diqester qas oxidation tank was rebuilt: it is reported that there is now no emission of
sulfurous oases from the diqester relief blow tank system.
7.
A scrubber was installed on the chlorine dioxide storage vent.
In addition to these changes, it was reported that a new blow heat recovery system and a
scrubber for bleach plant chlorine vents were expected to become operational during the latter
part of 1966.
DIGESTER AND BLOW SYSTEM
Diqester relief and non-condensable qases from the blow heat recovery system ordinarily are
rich in hydroGen sulfide, mercaptans, and organic sulfides. The present practice of scrubbinq
all qases from diqester relief and the blow system operation with a chlorine and water solution
appears, on the basis of reported data, to be effective in reducino emissions of these odorous
gases. This system operates effectively, however, only when sufficient chlorine is available to
contact and react with the sulfurous oases. This is especially important during periods of peak
qas flow. The chlorine-water solution leavino the scrubbinq unit should be routinely monitored
for residual oxidant content, and means should be provided for supplemental chlorine when the
scrubbinG medium supplied from the bleach plant is inadequate.
27
-------
28
MU l TI PlE-EFF HT EV APORA TION
Non-condensable qases from multiple-effect evaporators are among the kraft mill emissions
having the greatest concentrations of malodorous gases. Emissions from the evaporators represent
about 10 percent of the hydrogen sulfide and about 30 to 40 percent of the orqanic sulfides and
mercaptans reported to be emitted from the mill. The proportion of total pulp mill emissions
released from this source is unusually hiqh. Control of evaporator emissions has been accomplished
in other mills by scrubbinq with an oxidizinq medium such as chlorine solution. Incineration,
by catalytic oxidation or in lime kilns or recovery furnaces, 1S also a possible means of control.
An enqineering evaluation should be made to determine the feasibility of ducting all non-
condensable gases from the multiple-effect evaporators to the chlorinated water scrubbing system
presently used on the digester and blow system relief gases. This change would approximately
double the gas flow through the scrubbing system, and thus would require an increase in liquid
throughput, and possibly an increase in scrubber size.
Evaporator and blow condensates can be sources of odorous gases when sewered or used
elsewhere in the pulp mill process. One suggested control process is steam stripping of such
condensates and incineration of the odorous gases produced.
DI RECT -CONT ACT EV APORA TORS
Common practice in kraft pulp manufacturinq in the United States is to concentrate strono
black liquor to 60 to 65 percent solids in direct-contact evaporators. In this type of
evaporator, strong black liauor is contacted directly with the hot flue gases from a recovery
furnace. These flue gases contain nitrogen, some oxyqen, water vapor, and about 10 to 12 percent
carbon dioxide. They also contain minor amounts of sulfur dioxide and may contain odorous
sulfides, including hydroqen sulfide. The black liquor in contact with these gases contains
sodium sulfide and other alkaline sodium salts as well as dissolved materials from wood. Two
types of direct-contact evaporators are used in the Lewiston mill: furnaces number 1 and 2 are
equipped with disc-type units with rotating transfer surfaces; furnace number 3 has a venturi
evaporator equipped for steam atomization.
The equilibrium partial pressure of hydrogen sulfide above the black liquor is given by the
rel ati onshi p,
PH S =
2
(K)
(CNa S)
2
(CH+) ,
in which PH S is the equilibrium pressure of
concentratibn of sodium sulfide and hydrogen
proportionality constant.
hydroqen sulfide above a solution in which the
ion are CNa2s and CH+' respectively. The term K is a
When carbon dioxide contacts the alkaline black liquor, the qas is absolted and the pH of
the liquor decreases (CH+ increases). As a result, PH S increases and hydro~en sulfide tends to
be released from the black liquor. Methyl mercaptan ~s also released by acidification of its
sodi um salts.
-------
29
As shown by the equilibrium equation, the release of hydrogen sulfide during direct-contact
evaporation can be reduced in two ways: (1) by maintaining a high pH level (low value of CH+) in
the black liquor (since the liquor is in contact with the flue gas stream that contains a large
proportion of carbon dioxide, this usually is not practicable) and (2) by reducing the concentra-
tion of sodium sulfide (CNa S) to zero or as near zero as is possible. The latter can be achieved
by oxidizing the sodium sultide in the black liquor, thus converting it to sodium thiosulfate.
When the complete conversion of sodium sulfide is achieved, CNa S is zero and PH S also is zero.
If the liquor is thoroughly oxidized before it enters the direc~-contact evapora~or, the release
of hydrogen sulfide from this source may be greatly reduced.
The oxidation of weak black liquor was attempted at the Potlatch Forests, Inc., mill. The
attempt was unsuccessful, however, because of the stability of the foam produced, and the effort
was abandoned. Oxidation of strong black liquor prior to direct-contact evaporation should be
entirely feasible.
Non-contact type forced-circulation evaporators have been used for concentrating black liquor
to 60 to 65 percent solids in other countries. Hot flue gases do not come in contact with the
black liquor in such evaporators. Less hydrogen sulfide is formed, and none of it or of other
sulfurous gases are released to the flue gas. Non-condensable gases released from the black
liquor in the evaporation process can be treated in a gas scrubbing system such as that serving the
digester vent system or incinerated in the recovery furnace. Although use of forced-circulation
evaporators is reported to effect heat economies,ll! it increases the complexity of operation and
has higher initial and maintenance costs than does use of direct-contact types. Oxidation of
strong black liquor would seem to be the more feasible approach for the Lewiston mill.
RECOVERY FURNACES
Two recovery furnaces in the pulp mill are served by an electrostatic precipitator with a
reported particulates collection efficiency of 95 percent. Even with this collector these
furnaces emit more than 5,000 pounds of particulates per day. Effort should be made to
increase the efficien~y of the precipitator or otherwise decrease the emission of particulates
from the furnace stacks. Substantial improvement could be expected from secondary scrubbing
of the flue gases. Particulate emissions from the third furnace are still a major problem.
The existing venturi scrubber, with a reported collection efficiency of 74.2 percent, is not
adequate and should be replaced or followed by another control device such as a high-efficiency
electrostatic precipitator. Recommended practice for control of dust emissions in combustion
for indirect heat exchangers~ having heat input equal to the three recovery furnaces would
limit emissions to about 5,000 pounds of inert particulate per day even for locations in flat
terrain. The valley location and the chemical nature of emissions from the recovery furnaces
justify limiting emissions to a substantially lower value.
Odorous sulfide emissions from the recovery furnaces can be reduced by proper furnace operating
conditions, namely:
1. Adequate excess oxygen for complete
2. Thorough mixing of furnace gas with
3. Adequate combustion temperature and
combustion.
combustion air.
time to complete
the oxidation reaction.
The furnaces are reported to operate in the range of 0 to 3 percent excess oxygen. Oxygen
content in the flue gas leaving the furnace should be at least 3 percent by volume. Since a
-------
"0
reducinq atmospllere must be maintained in the 101'Ier part of the furnace to reduce the sulfide
l.n~lpounds, this ,Illditional air must be injected into the oxidizinll zone of the furnace. Data
provided by PoUctich Forests, Inc., indicate that none of the three furnaces is overloaded;
tlil:refore, maintendllce of 3 percent excess oxyqen in the flue qas should not cause overheating.
rilC presence of COIl1uustibles in furnace flue CJases is an indication of need for additional
~r'condary COliluustion air. ~10nitoring of flue qases for combustibles can be a valuable aid in
:I,lintaininq IlI'opcr furnace operation for odor control.
PERSONNEl RESPONSIBILITIES
Installation of air pollution control enuipment is only part of the solution to kraft ~i11
odors. Opprating or maintenance personnel must be assiqned responsibilities to ensure that a11
control enuipment is operating properly. Consideration should be given to desiqnatinq one
person directly responsible to manaqement as pollution control officer for the mill. In the case
of Potlatch Forests, Inc., this person would probably be the effluent enqineer. His duties
should include the location of odorous emissions, rellu1ar testing to ensure that control equipment
is operatinq well, recommendations for additional control equipment, and submission of periodic
repurts to the mill manaqer on pollution releases and equipment operation.
CONTROL OF COMMUNITY EMISSIONS
The control of community emissions depends 1aroe1y upon performance by individual citizens.
The prO[1er maintenance of automobiles and furnaces and the disposal of trash by a scavenoer or
by lJUryinq all help reduce the local air pollution burden. r.1andatory collection of all refuse
should be practiced in both Lewiston and Clarkston, and in the unincorporated areas adjoininq
these cities. All refuse should be taken to a landfill area and buried, not burned.
Smoke from the teepee burners in this area is another local problem. Burners observed
in thl' fall of 1966 were poorly operated and in need of repair. Periods of hiqh charqinq rate,
too much dilution air, and inadequate mixinll of air and combustion qases are some of the main
problems. Strowl pfforts should be made by the operatinq companies to eliminate smoke from
these burners. Prohibition of these burners should be considered if smoke abatement practices
are not successful.
No industri.-Il process I'lith a history of atmospheric pollution problems
to locate in Lewi<,ton or Clarkston without specifyinq in detail the type of
equipment they aqree to install. These plans should be subject to approval
control officials of both Idaho and Washinqton.
should be allowed
air pollution control
by air pollution
-------
SECTION VIl-METEOROlGY
EFFECTS OF TERRAIN
Topography and its effects on the atmosphere more than anything else affects the
behavior of air pollution in Lewiston, Idaho, and Clarkston, Wash. Because of the valley
configuration, particularly the wall-like hills risinq about 2,000 feet on the north side
of the Clearwater and Snake Rivers, north and south winds are greatly weakened and usually
fail to penetrate to the valley floor. Air movement is channelled to move either east or
west along the Clearwater River and the east-west portion of the Snake River in the
vicinity of Clarkston.
In addition to obstructing and channelling the wind, topography causes air motion
where the uneven surface of the ground heats and cools unevenly. Incoming solar radiation
results in air pollution moving upslope, or up valley, as the heated air rises; whereas
the loss of heat from slopes or high ground during hours of darkness causes it to move
down the valley as the cooled, more dense, air drains to a lower elevation by the force
of gravity.
Described above is what may be called "normal" behavior of the air resulting from
effects of topography. Variations in this behavior are caused by the action of meteoro-
logical features of cyclonic scale, for example, the occasional passage of a low-pressure
system with some local frontal activity. The low-pressure systems are usually associated
with strpnger westerly winds aloft that come lower with the approach of the disturbance
and sometimes reach the ground, causing gusty conditions that ventilate the valley.
EFFECTS OF ClOUDS, FOG, AND SNOW COVER
Other factors that disturb the normal behavior of the air are overcast skies, fog, and
snow cover. Overcast skies not only reflect incoming solar radiation from cloud tops, they
also act as a blanket, reducing heat loss from the ground so that surface temperatures are
more uniform and at the same time reducing the effects of ~opography.
Fog has a similar effect, but it is also important that the top of the fog layer acts
as a radiating ~urface at night. The top of the fog layer cools and intensifies a trapping
temperature inversion layer aloft. Consequently, with the cooling aloft, a vertical
temperature profile develops in the fog layer, so that air pollutants in stack plumes are
carried to the ground.ll! This process is illustrated in Figure 3. Fog has occurred with the
most serious air pollution incidents in the Lewiston-Clarkston area.
31
-------
32
SHORT-WAVE
RAOIATION
cr
LONG-WAVE
RADIATION
VAllEY FDG"t;t~~~~ I ~::;:u~
NIGHT HEIGHT CURVE
Figure 3.
Function of fog in maintaining valley
stabil ity.
The worst air pollution conditions occur with complex, multi-layer, inversions that
occur when a stratus cloud overcast persists over the area for several days and fog forms at
the valley floor. Solar radiation is insufficient to penetrate both of these layers and
warm the ground sufficiently to destroy the surface-based inversion. Under these conditions
air pollutants continue to accumulate from day to day.
Adams s ta tes, "Some 20 days of heavy fog are recorded annually in the valley. Fog
formation may on occasion be accentuated by large volumes of steam introduced into the valley
air. This steam rapidly disappears as the relative humidity decreases. However, during the
winter months of 'higher relative humidity, the steam may persist and become indistinguishable
from natural fog."Y
During rainy, damp weather the odor of the pulp mill sometimes seems unusually strong.
The stronger odor may in part result from the more acute sense of smell associated with a
moist atmosphere, or may be the result of down currents caused by the falling precipitation.
As already stated, vertical mixing of the air can occur below an inversion lid when there is
a fog; this may occur with or without precipitation.
Snow cover reflects solar radiation so there is less surface heating and upslope and up-
valley winds may not develop. At night, snow is a much better radiator of heat than bare
ground and colder more dense air results. Downslope winds and downvalley winds are likely
to be stronger, and valley inversions can be expected to be deeper and more intense when
the ground is snow covered.
-------
33
WIND SPEED AND DIRECTION
Lewiston seems to have the lowest average annual wind speed of any city for which
U.S. Weather Bureau records are available. The annual average for a period of ?3 years at
the Weather Bureau City Office location in downtown Lewiston was only 3.8 mph.l1IThe
following average annual wind speeds in other cities are given for comparison:
Los Angeles (Civic Center),Calif.
Salt Lake City, Utah
Kansas City, Mo.
Washington, D. C.
6.2 mph
8.8 mph
10.0 mph
9.5 mph
Lewiston also has a high percentage of calms, which occur mostly at night and during
the early morning. At 0400 hours in the fall 28.3 percent of wind observations were calm.
The predominant wind direction is east; wind from this direction occurs 27 percent of the
time annually. (U.S. Weather Bureau City Office, December 1927-November 1932). East winds
occur most nights and during many daylight hours in winter. Westerly winds are most
frequent during the afternoon.
During the period Oct. 5 through 11, 1966, a brief meteorological investigation of the
Lewiston-Clarkston area was conducted by Abatement Program personnel. During this period,
a variety of conditions were observed. There were both clear and cloudy skies and two
periods of rain. Winds were generally light, although on one day wind speeds were
moderately strong. Neither significant fog nor a period of prolonged atmospheric stagnation
occurred. Forty-five upper wind soundings were taken, and Weather Bureau .records on file
at the airport were examined for possibly significant observations.
Upper wind soundings were taken from the Lewiston Fire Station, 13th and F Streets,
elevation 740 feet MSL~ The period of observation was October 5 throuqhll. Regular
observation times were 0500, 0700, 0900, 1100, 1500, 1900, and 2300 hours; however,
observations were also made at other times at the discretion of the observer. Pilot balloons
used for the soundings were tracked by theodolite for 8 minutes whenever possible;
observations were recorded at 20-second intervals. Based on a standard rate of ascent for
a balloon, an 8-minute sounding made possible calculations of wind speed and direction up to
an elevation of 3,560 feet above surface, which is an elevation 1,700 feet above the top of
the Lewiston Hill.
Results of the upper wind soundings are tabulated in Appendix B. The data are notable
primarily for the very low wind speeds that were especially common up to several hundred
feet above the surface, and for the large changes in wind direction, sometimes even reversals,
with increasing elevation.
TEMPERATURE INVERSIONS
When there exists a large decrease of temperature with height, the air is unstable and
mixing occurs readily; however, when there is a small decrease, or an increase of temperature
-------
34
with height (i.e., an inversion), the air is stable and vertical motions are damped out.
Inversions are more intense in a valley than over flat terrain because the coldest air seeks
the lowest elevation and pushes aloft the warmer air.
Instrumentation for the Adams study included two wind speed and direction recording
systems, one on the north side of the Snake River northwest of Clarkston and one in
Clarkston.l! Wind data were also obtained from a third station at lewiston Airport. A
lOa-foot meteorological tower was operated for 10 months at the first-mentioned site for
recording temperatures at six levels, or temperature inversion data. Figure 4 and Figure 5
taken from the Adams report show the percentage of the days per month inversions occurred
100
90
Co?
>-
'""
= ao
LL.
=
>-
:z:
.......
~ 70
.......
Q...
60
1962 1963
50
F M M J J A S N 0 J F
E A A U U U E 0 E A E
B R Y N l G P V C N B
Figure 4.
Percent of days per
month having inversions.
14
12
10
~
-<=
z
=
>-
'""
a: 6
:::>
=
4
Figure 5. Average hours 1962 1963
of inversion duration.
0
F M M J J A S N D J F
E A A U U U E 0 E A E
B R Y N l G P Y C N B
-------
35
during the study period and the average durations of continuous inversions in the lower
100 feet of the atmosphere at the tower site. Shortest inversion periods occurred during
the late spring and early summer, whereas inversions persisted longer during the late fall
and winter months. The frequency of inversions is greater during summer than during winter.
The emissions from a tall stack, or air
at the source, remains aloft under inversion
unless it is removed by wind or permitted to
pollution that rises because it has been heated
conditions, but it is confined by valley walls
escape aloft by the dissipation of the inversion.
FUMIGATION
If a volume of air is displaced in an upward or downward direction in an unstable atmosphere,
the air continues to move in the up or down direction. In an unstable atmosphere the
temperature decrease with height is greater than loC per 100 meters (5.4oF per 1,000 ft).
Hardly any air pollution from the pulp mill results in the Lewiston-Clarkston area when the
air is generally unstable. Looping of plumes can cause high concentrations near the mill.
but this condition is most likely to occur du~ing the afternoon when westerly winds transport
the pulp mill plume away from the populated areas.
Moderately high concentrations of air pollutants from the pulp mill can be transported
interstate under neutral meteorological conditions. i.e., when the temperature decrease with
height is loC per 100 meters. Neutral conditions occur with windy or cloudy conditions or
during transitions between unstable and stable conditions. Neutral conditions with easterly
winds that transport air pollution from the pulp mill to Clarkston occur very infrequently.
By far the most important cause of high concentrations of air pollution at ground level
in Lewiston and Clarkston is the atmospheric process called "fumigation." Wherever the ground
receives solar radiation. the air heats from the surface upward. After sunrise a layer of
warm air is formed at the base of the stable 1ayer that fills the valley. and the layer
thickens as heating continues. When this layer becomes thick enough. convective currents
form within it. depending on the character of the surface. Significant factors would be
roughness caused by trees or other vegetation. man-made objects. and minor topographic
features. The upward-moving currents may. or may not. join together in a shallow up-valley
breeze at this time of day. Wind directions may be variable. or westerly; and wind speeds
3 to 7 miles per hour. However. with sufficient time, usually before mid-morning. the layer
of heated air becomes deep enough to reach the pulp mill plume spread out several hundred feet
overhead. Mixing of the material of the plume occurs throughout the heated layer. Although
the mixing seems to begin over Clarkston, or westward from there. where there may be more
surface heating. it works back to Lewiston. With continued TIeating as the morning progresses.
the layer in which mixing is occurring becomes deep enough to envelop all of the plume. At
first the plume material is brought nearly straight downward by the air currents. The material
in the plume that reaches the ground is relatively highly concentrated. since the plume has
never diffused much in the stable layer. Obviously. the rate of heating is a factor in
determining the maximum ground concentration and the duration of the generally high concentrations
resulting from fumigation. In the summer the average duration of the fumigation process may
-------
36
be 30 minutes to 1 hour, whereas in the fall and winter the average duration may be 2 or 3
hours or longer.
When viewed from a distance, the material being mixed downward during fumigation appears to
be uniform. It gradually obscures visibility between the ground and the plume without showing
any signs of the vertical currents causing the mixing. Following the fumigation, visibility
gradually improves. A change in horizontal visibility during fumigation is sometimes
noticeable for a brief period in downtown Lewiston and Clarkston, when a mid-morning haze can
be seen between the observer and objects such as trees or buildings a city block or two away.
Overhead, the plume becomes thinner and later becomes indistinguishable from the more tenuous
material mixed throughout the heated layer of air.
Near the pulp mill the vertical air currents, if strong, may cause looping of the plume
to the ground while the fumigation is taking place at some further distance downwind.
By the time the fumigation has been completed, wind directions are likely to be variable,
with light speeds, so the plume over the pulp mill rises nearly straight up under good
diffusion conditions, or if the winds have become westerly, the plume moves up valley away
from Lewiston.
Air pollution that comes down in fumigation over Clarkston can be carried back over
Lewiston with a west wind. This seems to be much less of a problem, however, than it
might first appear because of the strong vertical motions that are likely to be occurring.
Going westward, aloft, the plume remains concentrated; but returning and going eastward
toward the pulp mill, it is likely to be well dispersed. In some instances, heating is
sufficient to eliminate the stable layer in the valley and any air pollution is free to
escape upward. In this case, the valley quickly clears and ground concentrations are
inconsequential in the return flow.
Figure 6 illustrates the fumigation process.
There is also another situation when the pulp mill odor can be noticeable in downtown
Lewiston with a west wind. Odors from the water discharge of the mill at the confluence
of the Clearwater and Snake Rivers may be noticeable when the wind is light and the air is
stable, with little vertical mixing.
EPISODES
Air pollution potential forecasts of weather conditions conducive to accumulation of
air pollutants in the atmosphere are prepared at a facility of the National Center for Air
Pollution Control in Cincinnati, Ohio, by meteorologists on assignment from the Environmental
Science Services Adminstration (ESSA), u.S. Department of Commerce. These forecasts are
based on reports received hourly via teletype from the Weather Bureau stations in the United
States and on numerous analyses and forecasts provided by the National Meteorological Center
in Suitland, Md. Since the air pollution potential forecast program was begun for the
-------
>-
......
......
u..
1,000 --
I
I
I
I
I
I
I
I
--I I- 5.40 F
- TEMPERATURE +
SURFACE
COOLING
T
500
>-
......
......
u..
500
I
I
I
I
I
I
-1 f- 5.4°F
TEMPERATURE +
SURFACE
HEAT! NG
37
< "ST "" I ~,~,
jWJI;&jJiJ~jiJ~1lWE&!t~t~8~m~\~&$\il%i~~i!~;;\,
SOURCE Jfr\
CONOITIONS LATE AT NIGHT BEFORE FUMIGATION
, < "ST "" I ~
: FUM~i C:A.:r-1 ~.. WEST WINO 7"' SOURCE;~iiiJft!'
CONDITIONS AT MID-MORNIN~ OURING FUMIGATION
Figure 6.
The fumigation process.
western part of the United States in October 1963, air pollution advisories have been issued
for the Lewiston-C1arkston area for a total of 32 days during the periods listed below:
Nov. 30 - Dec.
Nov. 18 - Nov.
Jan. 16 - Jan.
7, 1963
22, 1964
19, 1965
Feb. 18 - Feb. 19, 1965
Oct. 23 - Oct. 28, 1965
March 25 - March 27, 1966
(No other advisories in year
1966)
Weather Bureau records at the Lewiston Airport were independently scanned
possible dates of high air pollution situations in Lewiston, Idaho. The dates
are listed below:
to determi ne
selected
-------
38
1961
1%5
aJanuary 10-22
January 8-13; 15-23; and 24 - February 12
November 4-10; 12-21; and 27 - December 3
aOctober 23-21
November 3-18 and 22-27
1962
December 5-11
January 28
February 1
February 15-21
March 5-8
1966
October 10 - November 3
February 17-22 and 24-26
March 8-14
November 12-17
aMarch 24 - April 1
April 3-9 and 17-24
December 7-12; 16-23; and 25-31
1963
April 29 - May 5
May 7-9
January 4-8 and 20-24
February 4-16 and 18-25
October 9-16
October 22 - November 14
aNovember 30 - December 7
November 17 - December 6
December 12-21
December 17-20 and 29-31
1964
alnclude dates of advisories.
October 21-28
aNovember 6-10 and 13-22
December 2-6 and 27~31
Meteorological conditions on these dates were characterized by an unusual number of hours
with smoke over the city or in the valley, sometimes with fog, and calm or light wind. The
periods that coincide with periods of air pollution advisories are marked. These dates would
not be expected to correspond exactly because air pollution potential forecasts are limited to
areas at least as large as 75,000 square miles (roughly the size of the state of Oklahoma), in
which stagnation conditions are expected to persist for at least 36 hours.
The report 999-AP-s!! contains a graph, "Seasonal Variation of Airport Observations of
Smoke Over the City, 1948-1959," which shows average days per month for which smoke was
reported in the valley for each month of the year. This graph is replotted in Figure 7,
which shows the days per month smoke was reported in the valley during each month of 1965 and
1966. Excluding January and February it appears that smoke in the valley was reported
considerably more often during 1965-66 than during the 1948-59 period.
-------
24
>-
LU
--'
--'
cr:
:>
::z: 20
C>
LU
I-
0:
C> 16
c...
LU
0:
LU
:..:
C>
~
v.> 12
=
I-
::z:
C>
~
0:
LU
c...
v.>
>-
cr:
C>
4
39
28
, [\
HOURLY OBSERVATIONS
-
U.S. WEATHER BUREAU ,. '< ~
- AIRPORT STATION
LEW ISTON, 10AHO I V ,\
" J .
\ \
) ",1966 1965 ~ / "
.
I~ ~\. I' / ' \
./ \
,,", J 'f"7 'c -...... I ) V \ ,
'- I
\ -" II "I 1"-\ I 1 / \
. J
/ i\. " i I / '
.
I ~ ', V 1/
) AVERAGE ~ ./
,,' 1948-1959 ~ V
~' ~
o
JAN
SEP
NOV
DEC
MAR
JUL
OCT
FEB
APR
MAY
J UN
AUG
Figure 7.
Seasonal variation of airport observations
of smoke over' the city.
-------
SECTION VIII-ESTIMATED CONCENTRATIONS OF AIR POLLUTANTS
ODOROUS GASES
It was reported that 1,660 pounds of sulfur is emitted daily from the pulp mill stacks
as hydrogen sulfide along with the same amount emitted as mercaptans. Meteorological
diffusion computations were made for four different conditions by using these emission
rates and the method of Turner and Gifford,15.16/ Table XI gives estimated concentrations
that would be expected in downtown Clarkston. A fumigation case is shown by photograph
and drawing in Figure 8. Effective stack heights for all stacks of the paper mill were
computed by using the method of Ho11and.lZ! Example of effective plume heights are given
below for neutral meteorological conditions:
2 and 3 evaporator
1 and 2 recovery
3 recovery
Effective
Height, m
38
71
70
(assumed wind
speed 2 mps )
Heights for stable conditions were computed to be somewhat lower.
Observations of the plume show that the calculated heights underestimate true heights
because practically all of the stacks of the paper mill act as heat sources and their plumes
merge. Other available methods of computing plume rise also do not fit this situation;
therefore. computations of downwind concentrations were made for effective stack heights
of 100 meters and 150 meters. since with light winds the height of the plume usually appears
to be within this range. In all but the uniform mixing case. ground concentrations would be
normally distributed across the long axis of the plume. The values given would occur beneath
this long axis. The effect of the shape of valley cross section was considered in the
uniform mixing case. but the valley walls did not seem to restrict the plume dispersion
significantly at a distance 3 miles downwind at the selected wind speed of 5 mph.
The report 999-AP-sli states that sampling station 6. i" Clarkston. yielded maximum
concentrations of 9 ppb under unstable conditions, 33 ppb under neutral conditions, and 44 ppb
under fumigation conditions. Adams gives average concentrations of H2S with respect to time
of day at station 1-2, also in C1arkston.1I For mid-day. when conditions are generally
unstable. he shows a concentration of about 5 ppb. and between 0600 and 0800. which are hours
possibly associated with fumigation, he shows about 13 ppb. He also presents monthly
distributions by hours for this station. These distributions indicate average peak fumigation
values of about 20 ppb during some months.
41
-------
42
~l .
.
'-p,,.
~
II
"
"
~
.,~.';.'
. .~.,.;. .
,.,.+" "7 "..
~
TOP OF PLUME 223 m
(CONCENTRATION AT GROUNO
lEVEL BEFORE FUMIGATION
19 ppb AT CENTER OF CIRCLE.)
FUMIGATION WINO SPEEO 5 mph ESTIMATED DOWNWIND
CONCENTRATION OF H2S OR MERCAPTANS
WASH I NGTON
IDAHO
Potlatch Forests, Inc.~
lewiston
".
o
I
Mi I es
Figure 8.
A typical fumigation of the study area.
-------
43
With wind speeds as low as 2 miles per hour «1 mps) and the possible reduction of
wind direction fluctuations caused by the valley configuration, the actual concentrations
may at times be double those shown in the Table XI. Both the estimates and the available
measurements indicate that concentrations of H2S and mercaptans range from about 5 to 50 ppb
over periods of 3 to 15 minutes in Clarkston most of the time when it is downwind of the
operating pulp mill, depending on atmospheric stability and wind speed. The estimates also
suggest that emissions of the pulp mill have not changed significantly since 1961-62.
TABLE XI
ESTIMATED DOWN~JlND CONCENTRATIONS
OF EITHER HYDROGEN SULFIDE OR MERCAPTANS
Distance, about 3 miles (5,000 m)
Rate of emission of H2S or Mercaptans:
1,660 lb/day of sulfur each
(Emission rate of H2S = 1,764 1b/day = 9.2 g/sec)
(Emission rate of mercaptans, assumed to be all methyl mercaptan,
CH3SH = 2,490 lb/day - 13.1 g/sec)
-6 3
NOTE: Calculated concentrations are the same for both gases. 1 ppb H2S = 1.4 x 10 g/m,
1 ppb CH3SH = 2 x 106 g/m3.
Concentration, ppb
Meteorological
Condition
3- to 15-min avg
2-hr avg
Wind speed
5 mph (2 mps)
H 100 m
9
22
19
27
16
H = 150 m H = 100 m H = 150 m
8 5 5
15' 13 9
5 11 3
22
13
Q
Moderately
Unstable
Neutra 1
Moderately
Stab 1 e
F . t. a
umlga 10n
Unifo~
Mixing
aFumigation concentration xf =
,12"; U cr H'
y
H = effective stack height
H'= H + 123 m. (123 m = estimated vertlcal extent of plume above effective
stack height)
Q = emission rate, g/sec
u = average wind speed, mps
cry= standard deviation of plume concentration in the horizontal
bRectangular cross section 1000 m (H + 123 m). No time limit.
-------
44
P ARHClflATES
Details of the physical characteristics Qf the approximately l2 tons of particulates
emitted dai-ly by Potlatch- Forests, Inc., operations arec unavailable. Hithout information
such as particle diameters and densities, a auantitative determination of the fall-out per
unit are~ of ground surface cannot be made. Particles of smaTl dia~eter, which make UP
the visible plume persisting after evaporation of moisture, al"e, however, consistently
carried over Clarkston and brought to the ground by ~tmospheric diffusion processes and
fumigation. Larger particles arpear as fine snow grains that are observed to fall from t~e
plume within a mile or two of the mill. Such grains are seen primarily in North Lewiston,
where on the ground they resemble a trace of snow. They fall through the air, blow over
surfaces, and accumulate in cracks and corners as would a dry snow. The distance these
larger, easily visible particles are carried depends on wind speed. They can on occasion,
however, be transported by the wind as far as downtown Lewiston or Clarkston.
WATER VAPOR
The report 999-AP-8 discusses the possible effect of the stack effluent from the
pulp mill on visibility within the Lewiston-Clarkston valley. In order to further
investigate this effect, downwind concentrations of water vapor were calculated for the
distance of Clarkston by using the reported rate of emission of water vapor, 9,000 tons
per day; and these concentrations were used to estimate the increase in relative humidity
caused by the pulp and paper mill emissions at three different temperatures. These estimates
are shown in Table XII. The relative humidities listed may be added to any existing relative
humidity of the air at the temperature shown ta obtain the resulting effect. For example,
if the relative humidity of the air would otherwise be 80 percent at 320F, fumigation with
a 5-mph wind speed would be expected to produce a relative humidity of 88 percent at ground
level; whereas 100 percent humidity, plus water droplets, would occur in the core of the
plume under moderately stable conditions. It can be seen from Table XII that the effect of
the plume is much greater at low temperatures.
The pulp and paper mill plume also contains solid particles too small to be visible
when the air is dry and they are well-dispersed. Such particles do, however, adsorb any
water vapor present and become effectivelY larger. The fact that the plume contains a
large amount of water vapor in addition to the particles means that it can be seen when
otherwise it. would be virtually invisible; and since the particles would be expected to
grow rapidly as the humidity becomes high, e.g., higher than 90 percent, the plume can be
an obscuring factor when the relative humidity is well below 100 percent.
Since at times the relative humidity of the air is high as a result of natural causes,
the estimated humidity increases seem consistent with visual observational data. This
would explain the frequently seen, cloud-like layer that often nearly fills the valley as
well as the considerable amount of fog that occurs during the colder months. When wind
speeds are very light the moisture added to the air in the valley is sometimes not cleared
out from one day to the next. It continues to accumulate and its effect increases until
a change in meteorological conditions removes it.
-------
45
TABLE XII
PERCENT INCREASE IN RELATIVE HUMIDITY
CAUSED BY PAPER MILL PLUME
AT DISTANCE OF CLARKSTON a
Condition
Temperature
100F 320F 500F
1.
Atmosphere Moderately
Stable
(Ground Level)
Atmosphere Moderately
Stable
(Plume Centerline)
Fumigation
(Ground Leve 1 )
Uni form Mi xing
10
12
5 3
25 13
8 4
4 2
tons/day.
2.
59
3.
18
4.
aRate of emission of water vapor: 9,000
Distance: 3 miles (5,000 meters).
Pressure assumed: 1,000 mb.
Wind speed: 5 mph (2 mps).
Concentrations averaged over 3- and 15-minute periods.
GENERAL COMMENT
The plume from the Potlatch Forests, Inc., mill is often a dominant feature of the
valley. If the mill were located in flat country, in an area where there is more natural
haze, or in a heavily industrialized, urban area as exists along parts of the East Coast,
the plume would be considerably less conspicuous to the eye. Aside from the fact that it
contains air pollution in the form of odors and particulates, it affects the behavior
of people and the economy of the Lewiston-Clarkston area in the following ways:
1.
There is no other' plume of remotely comparable size
the Potlatch Forests, Inc., plume is singled out as
feature.
The plume contains an enormous amount of moisture that under certain
frequently occurring meteorological conditions either can be seen or
noticeably obstructs visibility.
In absence of the plume, visibility would generally be unlimited except for
precipitation and some fog that would occur almost entirely during the
colder months.
The plume viewed from above can be clearly seen even when very tenuous
because it strongly refl ects 1 i ght. I-then seen from the. side, it is more
conspicuous against the walls of the valley than it would be against the sky.
Many persons travel into and out of the Lewiston-Clarkston area. Travellers
are reluctant to descend from the very clean, dry air of hill tops where
visibility is unlimited into the valley where the air appears to be less
clean. Upon leaving the valley they experience relief as they look back
at the obscuration below. Some people with real or imagined health problems
avoid travelling to Lewiston on days when air pollution may be high.
in the entire area; therefore,
a prominent and objectionable
2.
3.
4.
5.
-------
SECTION IX-EFFECTS OF ODORS
Of all man's senses, least is known about olfaction. The nose is so sensitive that no
scientific instrument approaches it in sensitivity 0; versatility as an odor meter. It can
respond to thousands of distinct odor stimuli and can detect odors in extremely dilute gaseous
concentrations.
Response to an odor is, however, almost entirely subjective. What is pleasant or
fragrant to one person may be unpleasant or malodorous to another. Kraft pulp mill odors are,
however, almost universally displeasing and repulsive; consequently, such mills frequently are
located in one-industry towns whose livelihood depends on the success of the mills. Although
communities that are economically dependent on such a single industry are not likely to
complain, people in neighboring jurisdictions, who may be less dependent and whose comfort,
enjoyment, and welfare are disturbed by the malodors, are not so tolerant or constrained.
Effects of odors on behavior have been given insufficient attention. It is known,
however, that the physiological processes of any individual with respiratory ailments are
adversely affected, however slightly, by odors and other air pollutants. Thus, the
condition of an afflicted person under the influence of odors is exacerbated to the level of
a person with a more advanced respiratory deficiency. This can result in loss of sleep,
general weakness, greater susceptibility to other diseases, irritability, loss of appetite,
and loss of work days.
Although he may not be greatly affected by low-level chemical and particulate pollutants,
a healthy. individual undoubtedly is affected by noxious odors. Odors may not cause organic
disease, but they can seriously affect a healthy individual's behavior adversely, both physio-
logically and psycholoQica11y.
Offensive odors such as those that originate from the Potlatch Forests, Inc., pulp mill
generally are recognized as capable of producing nausea, vomiting, and headache; curbing
appetites; disturbing sleep; upsetting stomachs; hampering proper physiologic breathing;
offending the senses; and interfering with comfortable enjoyment of property. They can mar
good dispositions and provoke irritability.
Sociologically, such odors reduce personal and community pride, interfere with human
relations in various ways, discourage capital investments, lower socio-economic status, and
damage a community's reputation. Economically, they can stifle growth and development of a
community. Both industry and labor prefer to locate in areas that are desirable places to
live, work, and play; the natural tendency is for them to avoid areas with obvious odor
problems. Tourists shun polluted areas. The resulting decline in market or rental property
values, tax revenues, payrolls, and sales can be disastrous to a community.
47
-------
SECTION X-DETERIORATION OF MATERIALS
SilVER TARNISHING
Metallic silver is sensitive to various sulfur compounds, especially hydrogen sulfide.
Hydrogen sulfide reacts chemically with metallic silver, causing a black-purple film or
tarnish upon the metal surface. Because of the sensitivity of silver to hydrogen sulfide,
the tarnishing of exposed specimens of the metal is often used as an indicator of hydrogen
sulfide in the atmosphere. The percent decrease in light reflectance from the exposed silver
plate is the generally accepted measure of the amount of tarnishing.
In the 1961 study of air
Clarkston, Washington, silver
reflectance in 30 days.
pollution in the Interstate Region of Lewiston, Idaho and
in the Lewiston area was found to lose about 45 percent of its
From May to December 1966, silver specimens were exposed for periods of approximately
1 month each at the State Highway Garage in North Lewiston. Exposures of these specimens
resulted in an average of about 86 percent decrease in reflectance. During the montns of
November and December 1966, silver specimens were exposed at three locations in the
Lewiston-Clarkston area and one location in Pullman, Wash. Results of these exposures, as
percent decrease in reflectance during 30-day exposures, are listed in Table XIII.
TABLE XIII
PERCENT DECREASE IN REFLECTANCE OF
METALLIC SILVER SPECIMENS - 30 DAY EXPOSURES
Location November, 1966 December, 1966
Pullman, Wash. 17 20
North Lewiston, Idaho 89 81
Lewiston, Idaho 77 54
Clarkston, Wash. 88 76
These results are indicative of the presence of hydrogen sulfide in the atmosphere
of the Lewiston-Clarkston area. Specimens from Pullman, Wash. show only moderate tarnishing.
49
-------
50
PAINT DAMAGE AND STEEL CORROSION
Potlatch Forests, Inc., has reported that particulate emissions from recovery furnaces
are currently 78.9 percent sodium sulfate and 13.2 percent sodium carbonate. The ratio of
sodium to sulfate in this distribution of sodium compounds is about 0.6 to 1.0, a relation-
ship that permits use of these chemical constituents as crude tracers for furnace
particulate emissions. Data reported for dustfall samples taken at the State Highway
Garage in North Lewiston during the period December 1961 through December 1962 show sodium
and sulfate as the major constituents. ~ The ratio of sodium to sulfate in these samples
is about 0.4 to 1. During the summer and early fall of 1966 qualitative dustfall samples
were obtained at the State Highway Garage in North Lewiston. These samples yielded a
sodium to sulfate ratio of about 0.6 to 1 and averaged about 40 percent by weight sodium
and sulfate.
Special dustfall samples have been obtained at or near the site of Henderson Motors,
Inc., in North Lewiston, only a short distance from the State Highway Garage. One of these
was taken on July 27, 1966, during a 2-hour period when the area was being showered with
white particulate material, and another collected in a piece of farm machinery over an
undetermined period of time; both yielded a sodium to sulfate ratio of about 0.7 to 1.
The latter sample contained sulfate, carbonate, and a minor amount of bicarbonate in
stoi~hiometric proportion to its sodium content. These sodium salt constituents accounted
for 43 percent of the total sample.
These data are consistent with reports by Potlatch Forests, Inc., of substantial
emissions of sodium sulfate and sodium carbonate from its recovery furnaces.
Particulates emitted from kraft pulp mill recovery furnaces have been associated with
paint damage and corrosion of ferrous metals in the Lewiston area. It is reported that
for a number of years v~hicles at the State Highway Garage in North Lewiston have suffered
paint damage and corrosion. Similar damage to vehicles has been reported and demonstrated
at the Henderson Motors, Inc., site in North Lewiston. Steel coupons exposed at the State
Highway Garage during the summer and fall showed only light to moderate corrosion. These
flat plate specimens were placed in the customary angled exposure position that does not
accumulate particulate when the surface is dry. Corrosion results indicate that the metal
surfaces were seldom wet during the exposure periods or that the gaseous components of the
atmosphere had only mild corrosive effect.
The mechanism of liquid blister formatio~ during prolonged immersion of paint coatings
on metal is of interest to paint manufacturers whose products may be applied to ships'
bottoms, dock works, water tanks, and similar structures. The mechanism has been described
by investigators concerned primarily with paint blistering in 3.7 percent sodium chloride
solutions, the concentration of sea water. ~ The mechanism is identified as
"electroendosmosis," which is defined as the movement of water through a capillary or
membrane under the influence of an electrical potential gradient. Studies showed that when
painted steel was submerged in sea water, blistering of the paint occurred shortly after
-------
51
corrosion of the metal occurred. The blisters occurred in the vicinity of the corrosion
but not at the corrosion site. The electrical force drawing the water through the paint
is that set up by the corroding metal itself.
Inspection of some of the vehicles at the State Highway Garage and at the Henderson
Motors, Inc. site in North Lewiston indicated that, in fact, the coating of paint on the
vehicles was not intact and was not protecting the metal surface underneath.
An investigation of the corrosive properties and the paint blistering capabilities of
sodium sulfate and sodium carbonate was undertaken by the Abatement Program, National Center
for Air Pollution Control. Results of this investig~tion indicated the following:
1. Sodium sulfate, a neutral salt, neither greatly inhibits nor greatly accelerates
corrosion of ferrous metal.
2.
Sodium carbonate, an alkaline salt, inhibits corrosion of ferrous metals.
3.
A mixed solution (4 to 1) of sodium sulfate and sodium carbonate inhibits the
corrosion of ferrous metals.
4. Sodium sulfate solutions, like sodium chloride solutions, are capable of blistering
paint from ferrous metal surfaces. This blistering capability is greatly accelerated
by nearby corrosion of the metal.
5.
Sodium carbonate solutions do not blister paint from ferrous metal surfaces.
6. A mixed solution of 4 parts sodium sulfate and 1 part sodium carbonate is
capable of blistering paint from ferrous metal surfaces.
7. A 10 percent solution of sodium sulfate caused blistering of paint after 16 hours
of exposure. The blistering was visible to the unaided eye.
8. A solution containing 10 percent sodium sulfate and 2.5 percent sodium carbonate
caused blistering of paint on steel in approximately 4 days.
9. In a laboratory trial. a 1 percent solution of the fall-out sample collected from
a farm machine adjacent to the Henderson Motors, Inc.. site blistered paint on st:ee'
in a period of 1 hour. In this trial only the painted side of the metal was exposed
to the sample solution while the unpainted side was subjectea to corrosion caused by
distilled water. A synthetic sample having the same proportions of Na2S04 and Na2C03
as the fall-out sample caused paint blistering under the same test conditions.
10. Seven different types of automobile paints were tested by submersion of
specimens of painted automobile body sheet metal in a 10 percent sodium sulfate solution.
-------
52
Three specimens blistered withi.n a 24-hour ~eriod and a fourth blistered during a 4-day
exposure.
It is concluded that
metal the paint was meant
the type of paint and its
damage to some types
to protect can occur
exposure to dustfall
of paint and subsequent natural corrosion of the
in the Lewiston-Clarkston area, depending upon,
rich in sodium sulfate.
-------
REFERENCES
1.
"A Study of Air Pollution in the Interstate Region of Lewiston, Idaho, and Clarkston,
Washington." PHS Publication No. 999-AP-8, U. S. Department of Health, Education, and
Welfare, Cincinnati, Ohio, December 1964,154 pp.
2.
"Cotmlunity Perception of Air Quality: An Opinion Survey in
PHS Publication No. 999-AP-10, U. S. Department of Health,
Cincinnati, Ohio, June 1965, 106 pp.
Clarkston, Washington."
Education, and Welfare,
3.
Adams, D. F., "Lewiston-Clarkston Air Quality Survey
Research, Insititute of Technology, Washington State
Project 662, April 1964.
- 1962." Division of Industrial
University, Pullman, Washington,
4.
Tuttle, W. N., and Adams, D. F., "A Source Inventory Study in the Vicinity of Lewiston,
Idaho and Clarkston, Washington." Division of Industrial Research, Institute of Technology,
Washington State University, Pullman, Washington, Project 0662, August 1962.
5.
Johnson, A. J., and Auth, G. H., "Fuels and Combustion Handbook." McGraw-Hill Book Co.
New York, New York, 1951.
6.
Hovey, H. H., Risman, A., and Cunnan, J. F., "The Development of Air Contaminant Emission
Table for Nonprocess Emission." Journal Air Pollution Control Association, 16(7) :362-366,
July 1966.
7.
Mayer, M., "A Compilation of Air Pollutant Emission Factors for Combustion Processes,
Gasoline Evaporation, and Selected Industrial Processes." Public Health Service, U. S.
Department of Health, Education, and Welfare, Cincinnati, Ohio, May 1965.
8.
Blade, O. C., "Petroleum Products Survey No. 31."
Center, Bartlesville, Oklahoma, September 1963.
U..S. Bureau of Mines, Petroleum Research
9.
Gerstle, R. W., and Kemnitz, D. A., "Atmospheric Emissions from Open Burning." Public Health
Service, U. S. Department of Health, Education, and Welfare, Cincinnati, Ohio, January 1967.
10.
Hansen, G. A., "Odor and Fallout Control in a Kraft Pulp Mill."
Control Association, 12(9):409-413, September 1962.
Journal Air Pollution
53
-------
54
11.
Harding, C. 1., and Landry,J. E., "Future Trends in Air Pollution Control in the Kraft
Pulping Industry." TAPPI, 49(8) :61A-67A, August 1966.
12.
Recommended Guide for the Control of Dust Emission -- Combustion for Indirect Heat Exchangers,
ASME Standard No. APS-1, The American Society of Mechanical Engineers, New York, New York, 1966,
13.
Schrenk, H. H., Heimann, H., Clayton, G. D., Gafafer, W.
in Donora, Pa. ," Public Health Bulletin No. 306, Federal
Service, Washington, D. C., 1949, 173 pp.
M., and Wexler, H., "Air Pollution
Security Agency, Public Health
14.
"Climatic Summary of the United States."
Washington, D. C., 1930 Ed.
Weather Bureau, U. S. Department of Agriculture,
15.
Turner, D. B., "Workbook of Atmospheric Estimates." Meteorology Program, National Center
for Air Pollution Control, Cincinnati, Ohio (In preparation).
16.
Gifford, F. A., "Atmospheric Dispersion Calculations Using the Generalized Gaussian Plume
Model." Nuclear Safety, 2(2) :56-59, December 1960.
17.
Holland, J. Z., "A Meteorological Survey of the Oak Ridge Area." ORO-99, Atomic Energy
Commission, Washington, D. C., 1953, pp 554-559.
18.
Kittelberger, W. W., and Elm, A. C., "Water Immersion Testing of Metal Protective Paints."
Industrial and Engineering Chemistry. 39:876-881, 1947.
-------
APPENDIX A
TRI-COUNTY AIR AND WATER QUALITY CONTROL COMMITTEE CHARTER
An unacceptable level of Air and Water pollution exists now in portions of the Tri-County
area. Unless reasonable standards of Air and Water quality control are established soon, the
expected increase of industry, commerce, and population may increase the now unsatisfactory
pollution levels to an intolerable point.
The Committee shall limit its activity and scope of operations to matters pertaining to
maintenance of a high standard of purity and quality for air and water resources.
The Committee shall undertake and pursue a course of action which will expeditiously lead
to recommendations for controlling and abating air and water po1iution incidents existing upon
creation of the committee; and shall establish and forward for enactment into ordinance,
resolutions, statutes and other controlling media, standards for air and water quality control.
The function of this Committee shall be advisory only; the regulatory and punitive
matters required to enact and enforce air and water quality control standards, ordinances,
regulations and like actions shall be the responsibility of the parent municipal corporation
or appropriate legislative body.
The geographic area of concern to the Committee shall include the entire areas of
Nez Perce County, Idaho, Asotin and Whitman Counties in Washington.
It is anticipated that this Committee shall function for a limited time only. Initially
the life of this Committee shall be limited to 18 months. If this term becomes impractical
and/or must be extended, such extension shall be voted upon by each member, agreement for
such extension must be unanimous.
Roberts Rules of Order will constitute the par1iamenta~y guide for committee operations
except insofar as this guide be in conflict with the committees' adopted policy rules or
regulation.
The operations, functions, and meetings of the committee being of public concern and
dealing with public matters shall be advertised in advance and shall be open to the news
media and the general public. Executive sessions with the general public and news media
barred therefrom are prohibited.
55
-------
56
The committee shall seek expert advice and opinion in its operations pertaining to
and water quality control investigations. Committee deliberation and decision however
remains at the discretion of the Committee.
air
From time to time, it may become necessary for the Committee to acquire and expend
public funds in the furtherance of its aims and goals. In these instances the Committee shall
request such required funds from the parent municipal corporation, each parent municipal
corporation providing its fair share based upon an agreed distribution.
If private funds become available by donation these may be accepted upon vote of the
Committee.
Upon dissolution, funds remaining under the control of the Committee shall be returned
to the apportioning municipal corporation in the same manner prorated as received.
In the event that the Committees' recommendations are disregarded, or refused by the
municipal corporation empowered to act in the instant matter, the Committee shall then find
itself a non-functioning entity serving no public purpose. In this event or in any case
where the Committee becomes a non-functioning body, its last official act prior to dis-
solution shall be to advise the appropriate State and Federal agencies that it cannot
function and invite their intervention to establish and enforce the required standards of
air and water quality control.
-------
APPENDIX B
PILOT BALLOON OBSERVATIONS, LEWISTON, IDAHO, OCTOBER, 1966
57
-------
Pilot Ca1100n Observptions, Lewiston, Idaho Vl
CP
October 1966
DATE: 05 05 06 06 06 06 06 Op 06 06 06
TIME: 2000 2200 0600 0612 0625 0800 0815 0830 1000 1010 1020
Ht Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel
ft 0 mph 0 mph 0 mrh 0 mph 0 mph 0 mph 0 f11ph 0 mrh 0 mrh 0 mph 0 mnh
0000 160 01 00 00 276 01 00 339 01 358 01 296 02 259 03 217 O~ 284 04
0170 120 03 094 04 071 02 076 01 042 01 349 02 301 01 268 02 265 02 226 04 199 01
0330 106 06 080 08 071 04 082 04 088 02 348 02 274 02 260 03 253 05 248 02 216 02
0500 100 06 078 10 064 04 073 05 072 04 307 02 267 03 260 04 251 03 310 01 226 02
0650 090 06 078 11 056 05 060 04 057 04 290 04 283 03 262 03 240 02 086 01 273 01
0810 090 06 078 12 051 04 048 02 025 02 290 03 316 03 q41 01 236 02 046 02 030 01
0960 090 06 078 12 041 04 035 03 018 01 019 02 035 02 214 01 063 04 046 03
1113 076 06 078 10 004 02 067 02 075 02 072 04 064 04 039 02 073 05 072 05
1267 055 02 084 10 037 02 074 06 094 04 080 08 078 07 069 04 097 06
1420 219 01 101 10 071 03 081 08 108 05 072 05 099 07
1573 203 01 108 06 065 06 Q98 08 138 06 074 04 099 07
1727 113 02 112 04 068 08 104 08 153 08 107 04
1880 092 02 145 04 082 10 153 12 110 03
2020 086 02 153 04 094 09 157 12 108 02
2160 079 04 171 05 108 08 166 11 104 02
2300 090 05 190 09 116 07 169 10 114 03
2440 117 05 192 12 122 08 125 03
2580 144 05 193 10 122 09 133 02
2720 169 05 193 10 171 03
2860 169 06 210 10 J77 05
3000 183 10 210 11 191 06
3140 188 13 210 14 209 06
3280 190 14 210 14
3420 195 15 212 14
3560 198 19 212 15
-------
Pilot Balloon Observations, Lewiston, Idaho
October 1966
DATE: 06 06 06 07 07 07 07 07 07 07 07
TIME: 1200 1709 2300 0500 0800 0905 0915 1100 1500 1800 1900
Ht Dir Vel Dir Ve"l Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel
ft 0 mph 0 mph 0 mph 0 mph 0 mph 0 mph 0 mrh 0 mph 0 mrh 0 mph 0 mph
0000 208 03 169 01 163 04 124 04 059 05 044 06 060 05 050 02 175 02 266 13 200 13
0170 184 04 041 01 095 06 099 06 Oc::' 05 073 06 069 04 063 02 231 02 279 14 211 14
0330 166 03 018 02 088 09 098 04 072 07 076 08 069 06 079 02 236 03 279 17 214 16
0500 157 02 352 02 075 12 017 02 078 06 082 08 069 05 082 04 263 02 279 17 235 11
0650 100 02 307 01 073 12 328 03 080 06 082 07 057 04 069 04 314 02 279 16 271 09
0810 102 02 252 02 073 10 299 02 083 06 071 06 052 04 069 03 316 02 279 17 280 14
0960 109 02 252 03 073 07 295 06 078 05 063 05 055 05 107 01 314 02 275 16 280 14
1113 112 03 256 03 073 06 296 10 040 03 067 05 071 06 136 02 336 01 270 14 280 12
1267 112 04 266 04 083 04 296 10 040 02 074 06 078 08 136 04 013 01 270 14 280 14
1420 112 04 282 04 110 03 295 08 048 02 074 07 083 07 147 05 303 01 273 14 279 19
1573 112 03 295 05 176 01 288 10 061 02 080 06 098 06 165 06 297 01 275 15 277 21
1727 130 02 300 06 285 04 280 16 114 02 104 06 124 05 196 05 296 02 275 15 277 17
1880 147 02 303 06 302 10 280 16 130 02 119 06 151 05 220 05 286 03 275 16 273 16
2020 118 02 303 06 306 11 282 14 142 03 127 05 160 05 235 05 286 04 269 13 269 16
2160 065 03 295 07 298 11 282 14 164 03 139 05 161 06 246 05 279 04 268 13 264 16
2300 059 04 296 08 289 12 282 14 171 04 151 06 170 07 247 05 264 04 268 12 255 18
2440 050 05 297 09 280 16 281 14 173 06 178 10 177 10 247 04 254 04 265 12 251 19
2580 038 06 301 10 275 22 285 13 178 08 192 12 162 10 247 05 248 04 265 12 251 18
2720 028 08 300 09 268 25 264 15 192 07 165 10 248 06 233 06 253 14 251 16
2860 023 09 298 09 263 22 255 20 197 07 169 10 248 05 226 07 250 15 248 16
3000 296 10 263 18 255 22 206 08 248 06 224 09 250 16 243 17
3140 293 10 260 18 216 08 248 06 223 10 250 16 243 18
3280 290 10 260 17 216 08 248 07 223 10 250 16 242 18
3420 284 09 260 19 216 08 248 07 222 10 250 15 240 16
35"60 284 08 260 22 216 08 248 07 222 09 250 15 240 16
\J1
\D
-------
Pilot Balloon Observations, Lewi s ton, Idaho
""
October 1966 0
DIIJE: 07 08 08 08 08 08 08 08 09 09 09 09 09
TH1E: 2300 0500 0900 1100 1110 1500 1900 2300 0500 0700 0900 1100 1500
Ht Dir Vel Dir Vel Dir Vel Di r Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Di r Vel Dir Vel
ft 0 mph 0 n1rh 0 mrh 0 0 0 0 0 0 0 0 0 mph 0 mph
mph f11rh mnh mph mrh mrh mnh mrh
0000 170 05 084 02 270 14 232 12 270 20 270 16 200 06 150 03 150 04 050 02 360 02 275 02 193 04
0170 097 05 092 04 270 16 250 12 252 22 257 20 227 09 193 04 120 04 090 03 025 02 316 02 214 02
0330 077 08 086 04 267 25 258 13 250 43 255 32 254 11 193 06 105 06 098 05 066 02 316 02 217 03
0500 075 06 107 01 268 25 265 21 253 48 257 32 261 14 197 04 105 08 086 06 066 03 307 02 194 03
0650 073 04 261 01 268 23 259 28 250 50 260 22 269 12 276 05 092 09 083 06 085 04 307 01 175 03
0810 089 02 268 04 268 22 263 32 245 60 263 20 271 16 291 08 092 08 081 04 087 06 319 01 160 03
0960 129 01 274 08 249 53 263 20 267 22 288 07 087 06 076 04 077 07 344 01 151 02
1113 231 01 275 18 249;,.24 263 18 265 17 278 08 082 06 083 04 068 06 057 02 194 01
1267 234 02 279 26 253 . 09 265 17 261 16 278 10 082 04 093 04 063 04 076 05 210 02
1420 224 04 274 20 253 06 265 19 260 14 283 10 109 04 099 04 070 04 090 05 212 03
1573 218 06 274 16 270 04 265 18 259 15 280 14 120 05 099 04 082 04 097 04 246 03
1727 224 07 270 03 267 18 253 16 273 14 120 04 099 04 106 03 107 04 284 05
1880 231 06 270 06 272 21 246 15 268 12 116 02 123 05 127 04 144 03 297 05
2020 249 07 275 10 272 20 248 14 27.0 14 115 02 151 06 117 05 189 03 285 05
2160 245 07 275 22 272 19 247 14 270 14 113 04 137 04 115 06 200 04 281 04
2300 264 12 275 34 274 20 248 13 270 16 140 07 126 04 129 08 198 04 288 04
2440 262 14 275 30 274 19 258 12 270 18 140 10 186 16 150 10 194 06 297 04
2580 233 11 275 20 274 22 267 12 267 18 117 08 194 20 169 09 187 07 303 04
2720 217 10 275 12 275 25 269 13 267 17 117 04 167 08 180 11 189 08 306 03
2860 210 10 275 14 275 22 272 14 267 16 172 03 179 08 184 11 195 08 304 03
3000 209 09 275 20 277 22 273 20 265 18 257 04 196 07 184 11 197 09 308 04
3140 209 10 275 12 277 22 273 23 265 18 277 10 188 05 182 11 199 09 301 04
3280 207, 09 278 24 273 24 265 18 270 10 198 03 180 10 202 09 296 04
3420 201 09 278 25 273 25 268 19 262 08 205 03 175 10 206 10 291 05
3560 200 10 278 26 273 25 268 20 261 09 205 04 175 10 205 10 286 05
-------
Pilot Balloon Observations, Lewiston, Idaho
Octobe r 1966
DATE: 09 10 10 10 10 10 10 10 11 11 11
TIME: 1900 0500 0700 0900 1100 1500 1900 2300 0500 0700 0900
Ht Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel Dir Vel
ft 0 mrh 0 mph 0 mrh 0 mph 0 mrh 0 mrh 0 mph 0 mrh 0 mph mrh mT1h
0000 181 02 170 01 00 020 01 245 02 180 02 00 00 00 130 03 045 02
0170 131 04 119 02 118 02 011 01 254 03 190 02 00 090 06 098 04 094 04 028 02
0330 112 04 103 04 111 04 264 01 254 03 190 02 00 072 09 084 07 086 06 066 03
0500 117 03 095 04 086 04 252 01 247 03 195 02 086 02 071 09 078 07 081 07 076 04
0650 080 02 094 03 059 03 345 01 245 02 212 01 040 02 071 10 065 04 083 06 084 04
0810 237 01 104 02 048 03 043 01 322 01 274 01 058 02 071 10 047 03 083 04 088 02
0960 298 02 131 01 059 03 058 03 053 02 274 03 080 03 071 10 043 03 083 03 068 01
1113 324 03 282 01 073 04 063 06 065 03 270 03 085 02 069 10 061 04 038 01 127 01
1267 341 04 265 02 073 08 063 08 087 04 265 04 102 02 069 08 086 04 049 02 210 01
1420 356 05 171 01 055 10 054 08 062 02 257 04 134 02 073 09 136 02 069 02 147 02
1573 006 06 072 05 064 08 060 07 027 03 256 03 157 02 078 07 204 01 165 04 184 02
1727 020 05 070 08 085 07 064 05 081 03 265 02 104 01 087 04 115 01 220 04 290 04
1880 024 05 078 08 108 07 106 07 092 05 278 03 055 02 094 05 159 02 238 04 301 07
2020 016 05 100 06 118 08 140 08 103 06 287 03 055 04 097 10 204 03 250 04 301 07
2160 012 06- 135 09 151 11 147 10 130 07 287 02 044 04 096 08 253 04 302 09
2300 007 05 147 10 164 14 150 14 160 08 302 02 054 04 096 04 270 05 302 12
2440 017 05 160 12 173 17 158 15 180 08 315 02 061 04 105 04 282 07
2580 037 03 169 18 180 18 180 13 188 04 315 02 084 04 112 04 287 12
2720 057 02 171 20 189 16 210 08 302 01 331 03 095 04 112 06 287 16
2860 064 03 175 22 193 12 245 06 043 02 010 04 104 05 115 04 287 18
3000 058 02 177 22 204 08 275 06 060 04 014 07 115 06 283 17
3140 058 03 180 17 208 06 275 06 052 04 014 07 120 06 280 19
3280 077 03 180 14 214 06 275 06 055 04 014 08 123 06 278 22
3420 106 04 180 12 228 08 278 06 046 03 012 08 123 06 278 24
3560 115 04 180 09 234 10 278 06 028 02 012 08 123 06 280 27
0'
------- |