United States
Environmental Protection
Agency
Office of
Research and
Development
Environmental Sciences Research
Laboratory
Research Triangle Park, North Carolina 27711
EPA-600/7-78-041
March 1978
POLLUTANT MEASUREMENTS
IN PLUMES FROM POWER
PLANTS AND CITIES
Summer 1975, February 1976,
and February 1977
A Project MISTT Report
Interagency
Energy-Environment
Research and Development
Program Report
-------
RESEARCH REPORTING SERIES
Research reports of the Office'of Research and Development, U.S' Environmental
Protection Agency, have been grouped into;nine series. These nine'broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring -
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this series result from the
effort funded under the 17-agency Federal Energy/Environment Research and
Development Program. These studies relate to EPA's mission to protect the public
health and welfare from adverse effects of pollutants associated with energy sys-
tems. The goal of the Program is to assure the rapid development of domestic
energy supplies in an environmentally-compatible manner by providing the nec-
essary environmental data and control technology. Investigations include analy-
ses of the transport of energy-related pollutants and their health and ecological
effects; assessments of, and development of, control technologies for energy
systems; and integrated assessments of a wide range of energy-related environ-
mental issues.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/7-78-041
March 1978
POLLUTANT MEASUREMENTS IN PLUMES
FROM POWER PLANTS AND CITIES
Summer 1975, February 1976, and February 1977
A Project MISTT Report
by
J. A. Ogren
D. L. Blumenthal
W. H. White
Meteorology Research, Inc.
Altadena, California 91001
Contract No. 68-02-2245
Project Officer
William E. Wilson, Jr.
Atmospheric Chemistry and Physics Division
Environmental Sciences Research Laboratory
Research Triangle Park, North Carolina 27711
ENVIRONMENTAL SCIENCES RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U. S. ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711
-------
DISCLAIMER
This report has been reviewed by the Environmental Sciences Research
Laboratory, U.S. Environmental Protection Agency, and approved for pub-
lication. Approval does not signify that the contents necessarily re-
flect the views and policies of the U.S. Environmental Protection Agency,
nor does mention of trade names or commercial products constitute
endorsement or recommendation for use.
ii
-------
ABSTRACT
Airborne measurements of aerosols and pollutant gases in urban and power
plant plumes were conducted during the summer of 1975, February 1976, and
February 1977, in the vicinity of St. Louis, Missouri; Moss Landing, Cali-
fornia; and Clearwater, Florida, respectively. The principal objective was
to characterize the physical and chemical behavior of these plumes under a
variety of meteorological conditions, with emphasis on sulfur transport and
transformation. Results illustrate the regional nature of air pollution.
The transport of well-defined urban plumes over 150 km downwind of a city was
documented during day and night conditions. Power plant plumes were sampled
over 100 km downwind of the source at night and during the day over the
ocean; strong dilution mechanisms limited the sampling of power plant plumes
to 40 km during the day over land. Measurements indicated that, when the
plume was not well mixed to the ground, the mass flux of sulfur in the plume
did not change with distance. In urban plumes, a significant reduction in
sulfur was found; only about one-third of the emissions were transported
beyond 100 km downwind of the city.
A new airborne impactor system was tested during the program. Sample
substrates were optimized for microscopy, but elemental composition of the
samples was also determined using ion-excited X-ray emission techniques. A
preponderance of sulfur was found in all types of samples (regional, urban
plume, power plant plumes). The dominance of sulfur in regional samples
obtained in a large scale hazy air mass is indicative of the role played
by sulfur in visibility reduction.
Atmospheric electrical measurements were made to test their effective-
ness in plume tracking. Power plant plumes were detected up to 90 km from
the source using conductivity and potential gradient sensors.
This report was submitted in fulfillment of Contract 68-02-2245 by
Meteorology Research, Inc. under the sponsorship of the U. S. Environmental
Protection Agency. This report covers a period from June 18, 1975 to
October 18, 1977, and work was completed October 18, 1977.
111
-------
CONTENTS
Abstract iii
Figure s .. vi
Tables vii
Acknowledgment viii
1. Introduction 1
2. Summary of Results, Conclusions, Recommendations 4
Results 4
Conclusions 10
Recommendations 10
3. Program Description 12
Urban plume 12
Coal-fired power plant plume 12
Oil-fired power plant plume 16
Regional sampling 19
4. Experimental Methodology 21
Aircraft description 21
Flight plans 21
Calibration 22
Data processing 24
5. Elemental Composition of Aerosol Samples 25
Introduction 25
Summary of results, conclusions, recommendations 25
Measurement techniques 27
Analysis 34
References 41
Bibliography 43
Appendix
A. Airborne sampling system for Project MISTT 52
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FIGURES
Number Page
1 Selected horizontal profiles of ozone concentra-
tion and bgCAT downwind of St. Louis on 11 August
1975 5
2 Ozone flow rates (in excess of background) in St.
Louis urban plume on three different days 7
3 Comparison of light scattering coefficient (bSCAT)
and vertical electric field (E) 9
4 Location of sampling programs 13
5 Traverse flight pattern for plume sampling 23
6 Airborne impactor system 28
7 Assembly drawing of MRI Model 1502 Inertial
Cascade Impactor 29
8 Jet configuration for 3. 0 /urn D stage (top) and
0. 4 n m D stage (bottom) 31
9 Elemental composition of aerosol samples (0.4-
3. 0 urn. dia) 38
VI
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TABLES
Number Page
1 Project MISTT Participants ........................... 3
2 Sampling Summary- -Urban Plume (St. Louis,
Missouri) ........................................... 14
3 Sampling Summary- -Coal- Fired Power Plant
Plume ( Labadie Power Plant) ......................... 15
4 Sampling Summary- -Oil- Fired Power Plant Plume
(Moss Landing Power Plant) .......................... 17
5 Sampling Summary- -Oil- Fired Power Plant Plume
(A Florida Power Plant) .............................. 18
6 Sampling Summary- -Regional Sampling ................ 20
7 Design of Cascade Impactor ........................... 29
8 Example of Elemental Composition Data, Impactor
Stage C (3.0-0.4 ^m diameter) ........................ 33
9 Summary of Significant Measurement Errors ........... 35
1 0 Impactor Sampling Summary .......................... 37
VII
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ACKNOWLEDGMENT
This work has been supported by the Federal Interagency Energy/
Environment Research and Development program through the EPA Division
of Atmospheric Chemistry and Physics, Aerosol Research Branch. We ap-
preciate the guidance provided by Dr. William Wilson, Director of Project
MISTT. We also appreciate the technical support provided by Dr. R. Husar
and Dr. N. Gillani of Washington University, Dr. B. Cantrell of the Univer-
sity of Minnesota, Dr. Ralph Markson of Airborne Research Associates, Dr.
Jack Durham of EPA, the other members of the Project MISTT team, and
the staff of MRI.
Vlll
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SECTION 1
INTRODUCTION
The fate of sulfur compounds emitted into the atmosphere from urban
areas and industrial processes has become an is sue of great importance in the
formulation of air pollution control strategies. As part of the EPA-sponsored
Project MISTT (Midwest Interstate Sulfur Transformation and Transport),
airborne samplingwas conducted by Meteorology Research, Inc. (MRI)inthe
plumes from oil-fired power plants in California and Florida, from coal-fired
plants in the vicinity of St. Louis, and from the St. Louis urban/industrial area.
Preliminary measurements were made during the summer of 1973, followed
by large-scale field programs in 1 974, 1975, 1976, and 1977. These aircraft-
based measurements were designed to provide data useful in answering many
unresolved questions about the transport, transformation, and removal pro-
cesses affecting atmospheric sulfur.
The principal objective of the MRI sampling programs was to charac-
terize the physical and chemical behavior of plumes (both urban and power
plant) under a variety of meteorological conditions. Particular areas of in-
terest were to:
1. Measure primary and secondary pollutant mass fluxes in
the plume at a number of distances downwind of the source;
2. Characterize plume behavior during daytime (well-mixed)
and nighttime (stable) regimes;
3. Determine the composition of aerosols in the plume and in
background air;
4. Document the transport, accumulation, and transformation
of pollutants in synoptic-scale air masses.
Analyses of the aircraft data were directed towards gaining a better un-
derstanding of the factors affecting the transport, transformation, and remov-
al of primary and secondary pollutants, particularly those containing sulfur.
Among these factors were temperature, solar radiation, humidity, vertical
mixing, wind velocity, background pollutant concentrations, and trace ele-
ment (catalyst) concentrations.
-------
During the sampling performed under this contract, two new aerosol
sampling techniques were tried. An airborne impactor system capable of col-
lecting aerosol samples for microscopic and elemental analyses was devel-
oped and used to collect samples during the summer 1975 and February 1977
field programs. A description of the system and analysis of the data from
the summer 1975 program are presented in Section 5. During the February
1977 field program, atmospheric electrical measurements (conductivity and
potential gradient) were made in conjunction with other aerosol measure-
ments to determine their usefulness as in-situ and/or remote aerosol indi-
cators (10).
The primary sampling platform for the work performed under this con-
tract was an instrumented Cessna 206, operated byMRI. Measurements ob-
tained by the Cessna 206 included SO2, NO, NOX, O3, light-scattering coef-
ficient (b), condensation nuclei, aerosol charge acceptance, aerosol size
distributions, temperature, dewpoint, ultraviolet radiation, pressure, and
position. The aircraft was equipped to collect aerosol samples for chemical
and microscopic analyses using cascade impactors and a size-segregating
sequential filter sampler. Data from the instruments, as well as several
status indicators, were recorded on magnetic tape cartridges approximately
once per second. During most sampling missions,the Cessna 206 was sup-
ported by a scout aircraft. The scout was used to locate the plume, to aid
in determining the sampling path for the primary aircraft, and to make lim-
ited measurements at far downwind distances. During the Summer 1975 field
programthe scout aircraft was a Cessna 182 operated by Washington Univer-
sity. During the February 1 977 program, a Bellanca Viking, operated by Air-
borne Research Associates, was used both as a scout and as the sampling
platform for the atmospheric electrical measurements.
Project MISTTwas a multi-year effort involving a team of several re-
search groups. Organizations that participated in Project MISTT are listed in
Table 1, along with a brief description of their responsibilities. Overall pro-
gram direction was provided by the Environmental Sciences Research Labora-
tory of the U. S. Environmental Protection Agency at Research Triangle
Park, North Carolina. The field programs in the St. Louis area were coordi-
nated by Washington University.
This report describes the field programs conducted during July/August
1975, February 1976, and February 1977. The emphasis is to describe the
MRI sampling programs and experimental methods, and to summarize the
results and conclusions of analyses of the MRI aircraft data. An analysis of
the elemental composition of aerosol samples collected during the summer
of 1975 program is also presented in this report. The previous field pro-
grams and analyses of the earlier data are reported in the final report for
the 1974 program(l). Where appropriate, significant differences between the
1974 program and later work are pointed out .in this report.
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TABLE 1. PROJECT MISTT PARTICIPANTS
Airborne Research Associates:
Argonne National Laboratory:
Battelle Columbus Laboratories:
California Institute of Technology:
Crocker Nuclear Laboratory
(University of California, Davis):
Environmental Measurements,
Inc. :
Environmental Quality Research:
EPA-Las Vegas:
EPA-Research Triangle Park:
Florida State University:
IIT Research Institute:
Meteorology Research, Inc. :
University of Minnesota:
Northrop Services, Inc. :
Rockwell International Science
Center:
Stanford Research Institute:
University of Texas:
Washington State University:
Washington University:
University of Washington:
Electric Field Measurements, Scout Aircraft.
Boundary Layer Structure and Dynamics, Dry
Deposition Rates. (ANL work was co-sponsored
by ERDA. )
Outdoor Smog Chamber Measurements of Sul-
fate Formation Rates in St. Louis, Gas Chro-
matographic--Mass Spectrometric Measure-
ments of Organic Vapors.
Development of a Super sensitive Sulfate Measure-
ment Technique, Sulfate Measurements--1974.
Aerosol Sample Analysis using IEXE techniques.
COSPEC Measurements.
Forecasting and other Meteorological Support,
Dry Deposition Studies.
Helicopter Measurements, Winter 1976, Aircraft
Lidar Observations, Summer 1976.
Program Management, Instrument Calibration,
Data Transfer, Measurements in EPA Mobile
Lab.
Aerosol Measurements Using the FSU "Streaker"
Sampler with PIXE Analysis.
Optical and Electron Microscopy.
Aircraft Measurements, Data Analysis, Meteo-
rological Interpretation.
Aerosol Size Distribution Measurements, Aerosol
Dynamics, Ground Measurements, Data Analysis,
and Interpretation.
Instrument Calibration, Program Coordination--
1977.
Pilot Balloon Operations.
Ground-Mobile Lidar Operations.
Effects of Charge on Aerosol Deposition, Reactive
Plume Models.
Detailed Hydrocarbon Analysis, Interpretation of
Ozone and Hydrocarbon Data.
Field Program Direction, Scout Aircraft Operations,
Data Analysis and Interpretation, Data Management
and Model Development^ Sulfate Determinations.
Ground-Based Measurements and Data Interpretation,
Sulfate Species Measurement, Air Mass Trajectories.
-------
SECTION 2
SUMMARY OF RESULTS, CONCLUSIONS, RECOMMENDATIONS
RESULTS
A total of thirty-one sampling missions were conducted during the sum-
mer 1975 (St. Louis, Missouri), February 1976 (Moss Landing, California),
and February 1 977 (Clearwater, Florida) field programs. Of these, nine were
devoted to urban/industrial plumes, six to coal-fired power plant plumes,
fifteen to oil-fired power plant plumes, and one to a study of synoptic-scale
hazy air masses. Urban and power plant plume studies were conducted both
day and night, and in some cases sampling continued into the following day.
Much of the oil-fired power plant plume sampling was performed over the
ocean.
Analyses of the data base resulting from these thirty-one sampling mis-
sions have yielded significant gains in understanding the physical and chem-
ical factors affecting the transport and transformation of primary and sec-
ondary pollutants. The major contributions of MRI to the airborne sampling
programs were to collect the aircraft data, analyze the meteorological fac-
ors affecting plume behavior and analyze the urban plume data. Other inves-
tigators studied the physical and chemical properties of plume aerosols, the
fate of sulfur in the plume, the properties of synoptic-scale polluted air
masses, and other related aspects of pollutant behavior. Both the results of
MRI analyses and of analyses performed by other researchers using data
collected by MRI during the summer 1975, February 1976, and February 1 977
field programs are summarized in this chapter.
Urban Plumes
A large portion of the data from the summer 1975 field program was
related to urban plumes. MRI analyses of the urban plume data are report-
ed in References 2-6. The results of these analyses were summarized by
by Wilson (7):
1. The urban plume of St. Louis significantly degraded the air
quality of communities as far as 150 km from the city on a
number of occasions. An example of such an occasion is de-
picted in Figure 1.
-------
URGANA
A POWER PLANT
• REFINERY
KILOMETERS
76-407
Figure 1. Selected horizontal profiles of ozone concentration and bSCAT downwind of St. Louis
on 11 August 1975. Profiles were recorded during traverses of profile baselines at
the following altitudes and times: (starting upwind of city) 455 m rnsl, 0744-0758
, CDT: 425 mmsl, 1019-1036 CDT; 610 m msl, 1245-1310 CDT; 760 m msl, 1442-
1058 CDT. Note that baseline concentrations are non-zero.
-------
2. The most conspicuous components of the St. Louis plume 50
kmormore downwind of the citywerethe reaction products
formed along the way, particularly ozone and light scatter-
ing aerosols (bSCAT).
3. Most of the aerosol responsible for the high bSCATand result-
ing decrease in visibility within the St. Louis urban plume
was formed after 1-Zhours reaction time in the atmosphere.
4. The width of the St. Louis urban plume did not increase much
beyond the 40 km width of the city.
5. The mass flux of excess ozone (i. e. , that above background)
in the St. Louis urban plume leveled off at about 1Z5 metric
tons per hour, as illustrated in Figure 2.
6. The St. Louis urban plume persisted overnight and into the
next day on at least one occasion. Sulfate aerosol concen-
trations of upto 60/*g/m3were measured in the earlymorn-
ing hours after following the urban plume for 18 hours.
7. Only about one-third of the original sulfur emissions in the
urban plume were transported beyond a radius of 100 km.
Formation of secondary sulfate aerosol was undetectable up
to a distance of 50 km (8).
\
Power Plant Plumes
Most of the power plant plume measurements conducted as part of work
described in this report (summer 1975, February 1976, and February 1977)
were related to oil-fired plants. Coal-fired power plant plumes were studied
extensively in the summer 1974and 1976 studies. Results of the power plant
plume measurements are:
1. Power plant plumes (oil-and coal-fired)were followed over
100 km downwind of the stack during the night. Except when
the plume was transported over the ocean (Florida study),
plume sampling during the daytime hours was limited to
within about a 40 km radius of the plant because of dilution.
Transport conditions over the ocean during the day were
similar to conditions over land at night.
Z. Within the limits of experimental uncertainty, when the
plume was not well mixed to the ground, the mass flux of
of sulfur in the plume did not change with distance (8).
-------
150
L-
.C
ui
5100
or
^
o
(_,_
^50
0
N
O
A * A •
B *
«
• 7/18/75
A 8/II/ 75
• 7/30/74
• A
. . -1 - I I
IOU
h^
100^
h-
a:
^
o
50 u-
LJ
^~
O
M
0
0
50 100
DISTANCE DOWNWIND,km
150
0
76-410
Figure 2. Ozone flow rates (in excess of background) in St. Louis urban plume on three different
day;s. Values are calculated from winds within the plume and the difference between
ozone concentrations inside and outside the plume. Downwind distances are measured
from St. Louis Gateway Arch.
-------
3. The sulfate formation rate in the oil-fired power plant
plumes studied appearedto be considerably lower at night
than during the day (9).
4. Fallout of sulfate particles may be a significant contri-
butor to ground sulfate levels near the stack for oil-fired
power plant plumes (9). This observation is based on a
limited amount of data, and requires additional measure-
ments for verification.
5. Dispersion of the plume is minimal over the ocean be-
cause of the lack of surface heating. Figure 3 illustra-
tes a plume traverse 40 km downwind of the source; the
plume was only 2 km wide at this distance, and at 90 km
downwind was only 5 km wide.
6. The use of atmospheric electrical measurements (con-
ductivity and potential gradient) for remote and in-situ
plume detection was shown to be an effective technique
out to 90 km downwind of the source (10). Figure 3 il-
lustrates the relationship between the light scattering co-
efficient and the electric field on a horizontal traverse
through an oil-fired power plant plume. The plume also
was easily detected by the conductivity measurement,
which showed a dramatic decrease while in the plume.
Elemental Composition of Aerosol Samples
The MRI airborne impactor system was developed and tested during
the 1975 sampling program. Microscopic analyses of the ninety-three aero-
sol samples collected with the impactor system in 1975 documented the fea-
sibility of the system for use in ambient aerosol sampling. Analysis of the
samples for elemental composition using ion-excited X-ray emission tech-
niques (IEXE) was seriously hampered by steps taken to optimize the sam-
ples for microscopic analysis. However, results of the elemental analyses
were in qualitative agreement with the microscopic analyses in that both an-
alyses indicated a preponderance of sulfur in all types of samples. Like-
wise, high sulfur concentrations were also found on the impactor samples
on those days for which analysis of the sulfate filter samples indicated high
sulfate levels. The predominance of sulfur in the regional samples, which
were collected in a large-scale hazy air mass, is probably indicative of the
contribution of particulate sulfur to visibility reduction in hazy air masses.
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scat
1-6-
0.8 -
2.0- 200
1.8 - 180
160
1.4 - 140
1.2 - 120
1-0 - 100
80
0.6 - 60
0.4 - 40
0.2 - 20
0855 EST 2/12/77
274 m msl
scat
•' V\/yv\.
_L
_L
1 2 3
CROSSWIND DISTANCE, km
Figure 3. Comparison of light scattering coefficient (bSCAT) and
vertical electric field (E). , Data recorded from two air-
craft flying in formation through an oil-fired power plant
plume 40 km downwind of the source.
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CONCLUSIONS
Air pollution in the midwest United States must be considered as a re-
gional problem in the formulation of air pollution control strategies. Both
urban and power plant plumes can be transported long distances. At night,
elevated plumes are isolated from the surface and can travel at least 100 km
downwind of the source in the absence of strong removal processes. These
pollutants can be mixed to the surface on the following day, creating ground-
level impacts not attributable to local sources.
In order to understand the contribution of any source to air pollution
levels in its vicinity, it is imperative to understand the history of the air
mass entering the source region. For example, the ozone concentration just
east of Decatur, Illinois, on 18 July 1975 was on the order of 0. 1 5 ppm.
Much of this amount was due to the St. Louis urban plume. Although the St.
Louis plume did not pass directly over Decatur, a shift in wind direction of
less than ten degrees would have caused this to happen. Under such condi-
tions, pollutants emitted from Decatur would be imbedded in the St. Louis
plume. Downwind of Decatur, the effects of the St. Louis plume could be in-
correctly attributed to emissions from Decatur. A similar scenario can be
imagined for the effects of a power plant plume far downwind of the source.
The meteorological conditions which appeared most conducive to long-
range transport of high concentrations were steady wind directions and lack
of vertical mixing. These conditions are most likely to occur at night or
over the ocean, when surface heating is not a factor. Plume behavior over
the ocean during the day is similar to that at night overland, except for the
effects of solar radiation on plume chemistry.
When SO2 is emitted near the ground, as from home heating units or
short stacks, the SO2 can be removed by surface removal mechanisms (dry
deposition). When SO- is emitted higher in the air, as from the tall stacks
of fossil-fuel-fired electric power plants , the SO^is diluted before it reaches
the ground, and the surface removal rates are reduced. Emissions may, in
fact, be trapped above an inversion layer and remain trapped for hours.
Thus, elevated stacks theoretically permit a longer residence time in the
ambient atmosphere for SO- and may actually enhance sulfate formation.
On the other hand, they provide for increased dilution of the sulfate and SO2
and thus reduce the impact of emissions in the vicinity of the source (7).
RECOMMENDATIONS
The field measurements described in this report documentedthe exis-
tence of long-range pollutant transport, however they did not define the geo-
graphical extent of long-range transport nor the frequency of occurrence.
10
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These two subject areas need to be better understood in order to define the
impact of the long-range transport of pollutants. We recommend further an-
alysis of the aircraft and supporting meteorological data to better determine
the meteorological conditions leading to the development of long-range trans-
port situations. This may allow the results of Project MISTT to be extend-
ed to other regions.
Further work is desirable in both analysis of existing data and collec-
tion of additional data. A wealth of plume chemistry data was collected dur-
ing Project MISTT, and only a small fraction has been analyzed in detail.
Analysis of these data should yield considerable insight into the chemical
transformation processes occurring in both urban and power plant plumes
and the meteorological factors affecting these processes.
Research areas where additional measurements are recommended are
the three-dimensional distribution of pollutants on a regional (synoptic) scale,
the behavior of plumes over the ocean, and the importance of particulate fall-
out as a sulfur removal mechanism from plumes. Measurements performed
over the ocean are an approximation of smog chamber experiments in the
free atmosphere, because of the virtual absence of surface sources and re-
moval mechanisms. Preliminary measurements of the three-dimensional
distribution of pollutants on a regional scale were performed on 1 0 August
1975, however much more work is needed to understand the factors affect-
ing the transport, transformation, and removal of regional-scale polluted
air masses. Finally, measurements made in February 1977 indicated that
particulate fallout might result in significant surface sulfate concentrations
near the stack, but much more work is needed to document the importance
of this effect.
11
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SECTION 3
PROGRAM DESCRIPTION
The overall program can be divided into four separate types of sam-
pling missions: urban, coal-fired power plant, oil-fired power plant, and
regional. Samplingwas performed during July/August 1975, February 1976,
and February 1977, at several locations across the United States (Figure
4). Summaries of all sampling missions are presented in this chapter. De-
tailed sampling maps, flight outlines, weather summaries, and data plots can
be found in the data volumes for this project (11, 12).
URBAN PLUME
Emissions from the St. Louis urban/industrial area were sampled dur-
ing July and August 1975. Other participants in urban plume sampling mis-
sions were Washington University (program coordination, scout aircraft op-
eration, field data processing), University of Minnesota (aerosol sizedistri-
tribution measurements), Environmental Measurements, Inc. (ground-based
correlation spectrometer SO measurements), IIT Research Institute (micro-
scopic analysis of aerosol samples), Northrop Services, Inc. (calibration of
gas analyzers), and Rockwell International (winds aloft measurements).
A summary of the nine urban plume sampling missions is presented
in Table 2.
COAL-FIRED POWER PLANT PLUME
Airborne sampling was conducted in the plume of the coal-fired Lab-
adie power plant during July and August 1975. The Labadie plant (2250 meg-
awatts) is located about 55 km west of the St. .Louis Gateway Arch. This
samplingwas performedas part of the summer 1975 St. Louis program, and
the other participants were the same as for the urban plume sampling mis-
sions.
A summaryof the six coal-fired power plant plume sampling missions
is presented in Table 3.
12
-------
OO
_,-. .1
LABADIE. ST. i
|POWER'HLOUIL
jPLANT x/__
MOSS
•LANDING
POWER \
n . . . , \
KILOMETERS
Figure 4. Location of sampling programs.
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TABLE 2. SAMPLING SUMMARY — URBAN PLUME (ST. LOUIS, MISSOURI)
Date
(1975)
Tin
7/18
7/21
7/22
7/28
7/29
b
7/30
8/7
8/11
8/12
Flight Times
(CDT)
Start
0657
-1215
0641
1051
1545
0638
~1115
0726
1237
1311
1724
1322
1854
2350
0505
1026
0803
0737
1139
1608
2007
0739
1236
Stop
-1115
-1340
0958
1451
1900
-1000
-1300
1126
1444
1640
1823
-1730
-2250
0405
0913
1246
0929
1106
1532
1723
2136
-1120
-1600
Tape
Cartridge
Number
120
127
134
135
406
415
416
408
409
452
453
454
455
456
457
458
459
418
422
423
423
426
427
Approx. Plume
Sampling Dist.
fkm)
8, 30, 50
50
25, 32
75, 100
135, 175
~I5
50
15, 50
105
10, 35
30, 50, 87
87, 120
150
190. 250
250
...
55
90, 150
240
32, 80
160
No. of
Sulfate
Samples
0
0
10 -
8
8
9
4
14
4
0
0
12
8
10
12
3
4
9
9
3
2
4
3
No. of
Imp actor
Samples
4
0
2
2
0
0
0
0
0
4
0
3
1
2
2
0
0
2
2
0
2
2
2
Comments
Urban plume sampling upwind and downwind of Alton/Wood
River industrial complex. Afternoon flight terminated due
to deteriorating weather conditions.
Long-range plume sampling out to Dccatur, Illinois. A de-
tailed analysis of this day Is presented in White et. al. , Science,
194, pp. 187-189, 1976.
Sampling to southwest of city. Light wind apeed conditions.
poor plume definition.
Sampling northwest of city. Alton/Wood River Industrial com-
plex and Portage des Sioux power plant plumes also sampled.
Plumes not detected at 105 km distance.
Sampling due south of city. Urban plume well defined at 35
km. Sampling terminated because of marginal weather con-
ditions farther south.
Long-range plume sampling to northwest of city.
Cross-calibration flight with EPA/RAPS helicopters.
Long-range sampling northeast of city. Sampling at 240 km
unsuccessful due to thunderstorm activity.
Sampling to east-northeast of city.
-------
TABLE 3.
SAMPLING SUMMARY--COAL-FIR ED POWER PLANT PLUME
(LABADIE POWER PLANT)
Date
(1975)
7/19
7/24
&
7/25
8/6
8/7
&
8/8
8/8
&
8/9
8/13
Flight Times
(CDT)
Start
0733
~13IO
2100
0138
1641
1732
2227
2208
0643
1037
Stop
~0950
~1415
~0030
~0440
~1950
2106
-0150
0145
0954
1059
Tape
Cartridge
Number
407
407
417
450
460
461
462
420
429
430
Approx. Plume
Sampling Diet.
(km)
10, 22
35
15, 25, 50
88, 145
10, 44
2, 18, 39
58, 80
16, 37, 93
8, 21
No. of
Sulfate
Samples
0
0
20
12
0
9
9
8
21
2
No. of
Impactor
Samples
0
0
4
1
3
4
3
4
4
2
Comments
Plume characterization to northeast of plant. Wind direction
variable In afternoon.
Nighttime sampling southwest of plant. Good plume definition
at 88 km.
Plume not detected at 44 km distance.
Strong vertical dilution of plume at 2 km distance. Only traces
of plume found on second flight.
Plume located at 93 km distance northwest of plant; however,
pronounced wind shift prevented further sampling.
Sampling east of plant but west of St. Louis. Second flight
aborted due to heavy rain.
-------
OIL-FIRED POWER PLANT PLUME
Oil-fired power plant plume sampling was performed at both Califor-
nia and Florida locations. Sampling at the Moss Landing plant (located near
Monterey, California) was performed during February 1 976, while the other
plant (located near Clearwater, Florida) was sampled during February 1 977.
Summaries of these two sampling programs are presented in Tables 4 and
5.
The Moss Landing plant has an installed generating capacity of Z175
megawatts, and is designed to burn gas and/or oil. Serious plume tracking
problems were encountered because the plant was operated mostlyon gas for
the duration of the program. In addition, that portion of the plant operated
on oil burned low-sulfur fuel oil (about 0.3 percent sulfur by weight). These
two factors resulted in very low plume SO2 concentrations; at a downwind
distance of 1 km, the highest measured SO2 concentration was 0.4 ppm.
Sampling at the Moss Landing power plant was terminated premature-
ly because of the low sulfur emissions. The aircraft data were processed
and submitted to the EPA Project Officer for review; however,a formal data
volume was not prepared because of the inapplicability of the data to analy-
sis of plume sulfur chemistry.
v
The oil-fired plant in Florida has a generating capacity of 525 mega-
watts. During the sampling program the sulfur content of the oil was about
2 percent by weight. Ten sampling missions were flown, and included sam-
pling at night and sunrise as well as duringthe day. Several tests were made
using a scrubber on the inlet of the NO/NOX monitor to evaluate the effects
of potential interferences for that instrument.
In addition to the Cessna 206, a single-engine Bellanca Viking, oper-
ated by Airborne Research Associates, was equipped to make atmospheric
conductivity and potential gradient measurements. This aircraft was used to
test the feasibility of using atmospheric electrical measurements for plume
tracking and to compare the electrical measurements with aerosol measure-
ments made by the 206 (10). The Bellanca also served as a scout aircraft to
locate the plume.
Other participants in the program in cludedNorthropServices, Inc. (pro-
gram coordination), Environmental Quality Research (meteorological sup-
port), Airborne Research Associates (scout aircraft, electric field meas-
urements), and Florida State University (aerosol sampling). The Florida
State University research vessel "TURSIOPS" was used as a platform for
tethered balloon meteorological measurements. In addition, Brookhaven Na-
tional Laboratory performed airborne sampling in the same area during the
period of study.
16
-------
TABLE 4. . SAMPLING SUMMARY--OIL-FIRED POWER PLANT PLUME
(MOSS LANDING POWER PLANT)
Date
(1976)
2/17
2/18
2/19
2/20
2/21
Flight Times
(PST)
Start
1218
1223
1123
1558
1110
1214
Stop
1603
1532
1524
1728
1156
1419
Tape
Cartridge
Number
501
502
503
504
505
Approx. Plume
Sampling Diet.
(km)
8
8
8, 18
34
'
1. 2. 5, 8
No. of
Sulfate
Samples
4
3
4
2
0
0
No. of
Impactor
Samples
0
0
0
0
0
0
Comments
Plume survey flight east of plant. Plant primarily burning gas
--750 MW generated by oil.
Sampling east of plant. Oil-fired generation 750 MW.
Sampling southeast of plant. Oil-fired generation 1450 MW.
Plume reconnaissance flight. Light wind conditions, plume
drifting over ocean. Oil-fired generation 1450 MW.
Plume reconnaissance flight—data recorded on stripchart.
only. Oil-fired generation 500 MW.
-------
TABLE 5. SAMPLING SUMMARY--OIL-FIRED POWER PLANT PLUME
(LOCATED NEAR CLEARWATER, FLORIDA)
Date
(1977)
2/7
2/8
2/9
2/10
fc
2/11
2/11
2/12
2/15
2/17
2/17
2/18
Flight Times
(EST)
Start
1359
1309
1640
2314
1602
0658
1413
0734
1357
0802
Stop
1745
1708
1900
0248
1930
1054
1725
0936
1758
1102
Tape
Cartridge
Number
201
202
203
204
205
206
208
209
210
211
Approx. Plume
SampUng Diet.
(km)
...
3, 40, 80
30, 50
20, 40
2-3. 45, 90,
135
3, 10
1, 3
3, 10
25, 1-3
No. of
Sulfate
Samples
2
4
0
3
3
5
2
3
5
3
No. of
Impactor
Samples
4
4
0
3
4
4
4
4
4
4
Comments
Sampling checkout of the plume concentrations and tracking
ability. Sampling over the Gulf of Mexico.
Plume characterization. Sampling over the Gulf.
Test of atmospheric electrical measurements for plume track-
ing. Developed sampling protocol, radio procedures, etc.
Sampling over the Gulf.
ments. Special NO, Experiment. Sampling over the Gulf.
Plume characterization. Special NO, Experiment. Arrro-
spheric electrical measurements. Plume located over land.
Sunrise experiment. Special NO, Bubbler Experiment.
Atmospheric electrical measurements. Sampling over the
Gulf.
Cross-comparison flight with Brookhaven National Laboratories.
Plume located over land.
Sampling underneath the plume to measure fallout. Eight Nucle-
pore filters were wing-mounted. Plume located over land.
Plume characterization- -coordinated with Florida State Uni-
versity aircraft. Plume located over land.
Plume characterization ~25 km downwind (over land). Sampling
underneath the plume for fallout (over the Gulf). Atmospheric
electrical measurements. FSU aircraft flying in the area.
-------
REGIONAL SAMPLING
On 1 0 August 1975, a special flight pattern was used to characterize the
distribution of pollutants across a synoptic scale hazy air mass in the Mid-
west United States. The approximate route of flight was frornSt. Louis, Mis-
souri, to Kansas City, Missouri, to Indianapolis, Indiana, and return to St.
Louis. This mission was conductedas part of the 1975 sampling program in
St. Louis, and the other participants were the same as for the urban plume
sampling missions (except that correlation spectrometer and winds aloft
measurements were not obtained). A summary of this mission is given in
Table 6.
19
-------
TABLE 6. SAMPLING SUMMARY--REGIONAL SAMP LING
N
O
Date
(1975)
8/10
Flight Times
(CDT)
Start
0503
1012
1514
Stop
-0840
-1400
-1800
Tape
Cartridge
Number
421
419
463
Approx. Plume
Sampling Dist.
(km)
...
-.-
...
No. of
Sulfate
Samples
13
21
5
No. of
Impactor
Samples
3
1
0
Comments
SU Louis-Kansas City- Chi llicothe, Missouri
Chillicothe-Indianapolis, Indiana
Indianapolis -St. Louis, Missouri
-------
SECTION 4
EXPERIMENTAL, METHODOLOGY
Operations of the MRI sampling aircraft were coordinated closely with
other participants in the program. The general mode of operations was to
use a scout aircraft to locate the plume and set up sampling routes for the
MRI Cessna 206. (The use of a scout aircraft was a major refinement of the
experimental methodology used in 1974. ) The 206 then made a detailed char-
acterization of the plume while the scout moved farther downwind and locat-
ed the plume again. Both aircraft were in contact with the operations head-
quarters, which provided guidance for in-flight sampling decisions and co-
ordination with the other program participants. The improvements in air-
to-ground communications were another important refinement over 1974.
The experimental methodology related to the operation of the Cessna
206 is described in this chapter. Additional information on experimental
methodology can be found in Reference 1. Descriptions of the experimental
methods used by other program participants, as well as the manner in which
the various sampling platforms were coordinated by the operations head-
quarters, can be found in the references in the Project MISTT bibliography
(Page 43).
AIRCRAFT DESCRIPTION
An instrumented Cessna 206 was used as the primary sampling plat-
form. The 206 instrumentation for this contract was similar, with slight re-
finements, to that used during the 1974 program (1). A discussion of the
Cessna 206 airborne sampling system is presented in Appendix A, along
with a list of the changes that were made to the system during this project.
FLIGHT PLANS
The basic flights plans for both urban and power plant plumes consist-
ed of a combination of constant-altitude traverses flown through the plume
21
-------
perpendicular to its longitudinal axis* and vertical spirals (soundings) flown
over a given point. These patterns allowed a detailed characterization of the
plume at a particular downwind distance. In addition, horizontal traverses
were flown outside the plume to characterize the background environment
(Figure 5).
After the plume was located at the desired downwind distance, ground
reference points were chosen to allowtraverse paths approximately perpen-
diculartothe plume axis. The 206 then made a number of traverses between
the endpoints at various altitudes. The number of traverses at each down-
wind distance depended on the vertical extent of the plume, but was usually
at least three, and sometimes ten, or more.
Following the plume traverses, a spiral was usually made as close to
the plume centerline as possible. This spiral extended from as near the
ground as possible to well above the plume (power plants) or mixing layer
(urban plumes). This completed the plume characterization at that distance,
and the aircraft then moved downwind and repeatedthe process. While trans-
iting between downwind distances, the aircraft flew outside the plume and
performed background measurements.
CALIBRATION
Several different systems were used for calibration of the continuous
gas analyzers on the aircraft. These systems were continually refined dur-
ing the course of the project. Specifics of the calibration system and pro-
cedures used for the February 1977 study are given in Appendix A. The pro-
ceduresused duringthe summer 1975 and February 1976 studies were sim-
ilar, although the systems were different.
Calibrations for the 1975 study were performed by Northrop Services,
Inc. A Bendix Dynamic Calibration System was used to dilute a 99.1 ppm
NO cylinder and an 11. 05 ppm SO- cylinder. Gas concentrations in the cyl-
inders were compared to NBS standard reference materials before and once
during the field program. Ozone calibration gas concentrations were deter-
mined using gas phase tit ration techniques. The accuracy of the flow regu-
lating capillaries was checked before and after the field program.
- It should be noted that it was frequently difficult to ensure that a given
traverse was normal to the plume longitudinal axis due to plume wander-
ing, and because the plume was essentially invisible except for near-
stack sampling traverses.
22
-------
o EVENT ON, TIME. ALTITUDE AND
ROUTE NOTED, IMPACTOR ON
O EVENT OFF. 1MPAUOR OFF
Figure 5. Traverse flight pattern for plume sampling.
Points A, B, C, and D are readily identifiable
ground reference points which are determined
to allow traverse paths perpendicular to the
plume axis.
23
-------
For the February 1976 study, a low-concentration span gas bottle
(—0.6 ppm) was used to calibrate the SO2 monitor. The stability of the SO2
concentration in the bottle was verified by analyses before and after the field
program. The ozone monitor was calibrated before and after the field pro-
gram using a Monitor Labs 8500 calibrator, which was also used to calibrate
the NO/NOX monitor before the field program. After the field program, the
NO/NOX monitor was calibrated by the manufacturer.
DATA PROCESSING
Processing of the aircraft data was performed in two phases: prelim-
inary processing in the field and final processing after the field program.
On-site initial processing allowed a rapid evaluation of the results of a mis-
sion and helped in the planning of additional missions. Initial processing was
performed by Washington University for the summer 1975 program. Data
tapes from the February 1976 field program were not processed until the
aircraft returned home. For the February 1977 program, the tapes were
shipped to Research Triangle Park, North Carolina, for preliminary pro-
cessing at EPA. An MRI data analyst on-site in North Carolina reviewed
the data for validity and proper instrument operation, and reported the re-
sults of this review to the field crew by telephone. The tapes were then
shipped to MRI for further processing, and preliminary plots of the data were
transmitted to the field crew by telecopier so that analysis could begin while
the field program was still underway.
Preliminary data processing consisted of copying the field tapes into
computer disk storage and producing stripchart plots of important parame-
ters, hard-copy raw data listings, and a 1/2-inch industry-compatible mag-
netic tape for use in further processing. The stripchart plots were used for
the initial analysis of the results of the mission, and the data listings were
used to provide inputs for further processing of the data after the field pro-
gram.
Final processing of the aircraft data was performed by MRI and the
University of Minnesota (UM). The size distribution data from the 1975 pro-
gram were reduced to final form and analyzed by UM; all other data were
processed by MRI. Final data processing at MRI consisted of converting the
raw voltage data to engineering units (e.g. , parts per million by volume of
O_, NO, NOX , SO2 ), flagging inoperative instruments, and applying cali-
bration corrections. A magnetic tape of the final data was prepared, as well
as hard-copy plots and/or listings of selected parameters for all sampling
runs. These plots were included in the data volumes for the project (11, 12),
along with sampling maps and summaries for each flight.
24
-------
SECTION 5
ELEMENTAL COMPOSITION OF AEROSOL SAMPLES
INTRODUCTION
During July and August 1975, impactor samples of atmospheric aerosols
were collected in the St. Louis, Missouri area as part of Project MISTT
(Midwest Interstate Sulfur Transformation and Transport). These samples
were collected to allow determination of aerosol size and chemical compo-
sition characteristics by microscopic analysis. Subsequent to the micro-
scopic analysis, the samples were analyzed for elemental composition using
ion-excited x-ray emission (IEXE) techniques. In this chapter, the sample
collection and IEXE analysis methods are described, and the results of the
IEXE analysis are presented. Results of the microscopic analysis were pre-
sented by Draftz et al (13).
Four types of samples were collected: coal-fired power plant plume,
St. Louis urban plume, background (outside of plume), and regional (sam-
ples collected over a large area between Kansas City, Missouri, and Indian-
apolis, Indiana). MRI's Cessna 206 was used to collect the samples. A total
of fifty-nine (59) impactor sample sets were obtained; each set consisted of
two size cuts plus a backup filter. The impactor stages had 50 percent col-
lection efficiencies (D n) of 3 and 0.4 jim diameter.
JU
SUMMARY OF RESULTS, CONCLUSIONS, RECOMMENDATIONS
For the 1975 sampling program, the impactor sample substrates and
collection system were optimized for microscopic analysis. Many of the
procedures used to optimize for microscopy were in severe conflict with the
requirements for elemental analysis. Some of the conflicting procedures
were the use of glass-fiber backup filters instead of Nuclepore, the absence
of a collection grease on the sample substrates, and the presence of a thin
layer of gold on the collection substrates. Elemental data were not obtained
from the glass-fiber backup filters because of incompatibility with IEXE an-
alysis. The size selectivity of the impactor was probably poor because of
the high possibility of particle bounce from the ungreased collection sub-
strates. Finally, the gold-coated substrates caused interferences that could
25
-------
not be accounted for; these interferences probably caused masking of some
elements and generation of spurious signals corresponding to other elements.
As a result of the system optimization for microscopy, the IEXE data
cannot be used to draw definitive conclusions. The data were evaluated on a
qualitative basis to gain a better understanding of the elemental composition
of the aerosol samples, however, even qualitative results must be tem-
pered by the high degree of uncertainty in the data. The results can be used
as an example of the type of information that is available using IEXE analy-
sis, and may provide an indication of the composition of aerosols in the St.
Louis area.
In general, the most common elements detected in the aerosol sam-
ples were silicon, sulfur, and chlorine. Together, these three elements
comprised over two-thirds of the aerosol mass. The abundance of sulfur in
the urban and power plant plume samples was expected because these sources
are rich in sulfur; the abundance of sulfur in the background and regional
samples indicates that sulfur-containing aerosols are widely distributed in
the atmosphere and must be considered as a regional-scale pollutant. Fur-
thermore, because the regional samples were collected in a very hazy air-
mass, the predominance of sulfur in these samples is probably indicative of
the role of sulfur compounds in visibility reduction in large-scale hazy air-
masses. Silicon and chlorine are largely of natural origin, and their rela-
tive abundance in all types of samples is indicative of their widespread oc-
currence in the atmosphere.
The aircraft sampling methods for power plant plumes caused a large
amount of background air to be included in the samples. The data reflect
this problem, because the composition of power plant plume samples is sim-
ilar to that of the background samples. The contribution of the power plant
is apparent in the data, however, because of the presence of such typical
power plant plume constituents as vanadium, titanium, and potassium.
The urban plume samples were notably lacking in lead, a major com-
ponent of automobile exhaust. Although interferences from the gold-coated
substrates could be the reason, another likely explanation is that lead-con-
taining particles were too small to be collected on the last stage of the im-
pactor. This hypothesis could not be confirmed because the backup filters
were not analyzed. Other missing elements in the samples (which would be
expected to be present) were calcium (a major component of soil) and iron
(power plant plume samples only). No explanation was found for the absence
of these elements, and further workwould be required to determine if their
absence is significant or an artifact of the sampling and analysis method.
26
-------
The airborne impactor system was proven to be a feasible way to col-
lect atmospheric aerosol samples. If optimized for analysis by IEXE tech-
niques, the system may allow identification of the contribution of various
sources to ambient aerosol concentrations (e.g., by using vanadium as a
tracer for power plants. For further applications of the system, it is rec-
ommended that the following items be performed:
• Calibrate size selectivity of impactor
« Optimize substrates for IEXE analysis (mylar substrates
coated with grease, Nuclepore backup filters)
o Use longer sample collection times
o Use plume sampling flight patterns that do not include
background air in the sample (e.g. , plume orbits)
• Collect a larger number of background samples
• Analyze a larger number of blank (control) samples.
Many of these steps have been implemented on subsequent power plant
plume sampling programs, and have yielded a large amount of information
on the differences between plume and background aerosol composition and
concentrations.
MEASUREMENT TECHNIQUES
Airborne Impactor System
The airborne impactor system consisted of four inertial cascade im-
pactors installed on the Cessna 206 in a wing-mounted pod (Figure 6). Aer-
osol size distribution measurement systems were also mounted on the air-
craft.
The impactor, based on an MRI commercial product, was designed to
collect particulate matter in several size ranges below 1 5/u m in diameter
(Figure 7). Modifications tothe commercial design were made to optimize the
collection of airborne samples. The airborne impactor consisted of two im-
paction stages and a backup filter. A third stage, intended to collect large
debris ( > 1 5/im diameter) which would generally not be of interest, was used
for the first two days of sampling. Use of this stage was subsequently dis-
continued because microscopic analyses indicated that very little material
was collected. The stage cutoffs for the flow rates used are summarized in
Table 7.
27
-------
00
Figure 6. Airborne Impactor System
-------
Nozzle
Jet Plate
Collection
Disc
1st Stage
O" Ring
Filter
75-II3
Figure 7. Assembly drawing of MRI Model 1502
Inertial Cascade Impactor.
TABLE 7.
DESIGN OF CASCADE IMPACTOR
Stage
A*
B
Diameter of
Holes (cm)
0.871
0.396
Number
of Holes
8
4 .
D50
(Mm)
14.5
3.1
Reynolds
No.
RN
1055
4654
Mach
No.
MN
0.056
0.054
0.053
4J10 each
; quadrant
0.39
3455
0.298
Temperature = 38 °C; Flow rate = 56 /pm
* - Used for only two days.
29
-------
One feature of this design which aided analysis of the last stages was the
placement of holes in clusters to concentrate the samples (Figure 8). Inlet
nozzles with an internal diameter of 0.48 cm were used. These nozzles al-
lowed isokinetic sampling conditions at an airspeed of 36 ms'1 fora flowrate
of 50z/pm. This nozzle diameter was chosen as a tradeoff between the opti-
mum diameters for the sampling speeds typically used for urban (49 ms~ )
and power plant plume (31 ms~' ) sampling.
The wing-mounted impactor pod provided aerodynamic stability for the
system. Each impactor was controlled from inside the aircraft by a sole-
noid valve. The inlet nozzles were, protected by a cap on a movable arm
which rotated out of the way when sample collection began. Quick disconnect
fittings were used to allow removal of the entire impactor, including inlet
nozzle, fromthepod. The vacuum source was an engine-driven carbon vane
pump.
Aerosol samples were collected on Nuclepore substrates mounted on
collection dishes below the jets. Most of these substrates were coated with
gold to optimize the experiment for microscopic analysis. The substrates
were not coated with a collection grease because of interferences with the
microscopic analysis. This increased the probability of errors in the size
selectivity of the system due to particle bounce-off. Glass-fiber backup fil-
ters were used to optimize the system for microscopic analysis. As will be
discussed later, the system optimization for microscopic analysis seriously
hampered the trace element analysis.
Impactors were assembled and disassembled in a clean room under a
filtered laminar-flow clean hood. Prior to assembly the impactor s and noz-
zles were washed with soap and water and rinsed with acetone followed by
distilled water. Careful handling procedures were followed to ensure that
the samples were not contaminated.
Aircraft Sampling Procedures
The basic flight pattern used for plume sampling was discussed in
Section4. Ingeneral, each plume impactor sample was integrated over sev-
eral of the traverses made at a particular downwind distance. Impactor
sampling was performed during an entire traverse, thereby entraining some
background air into the plume samples. Background aerosol samples were
obtained during special traverses made outside of the plume.
30
-------
75-109
Figure 8. Jet configuration for 3. 0 fim D stage (top) and
0.4/im D stage (bottom)
31
-------
Analysis of Elemental Composition
After microscopic analyses of the impactor samples were completed,
they were shipped to Crocker Nuclear Laboratory (University of California,
Davis )for determination of elemental composition. Ion-excited X-ray emis-
sion (IEXE) methods (14) were used to determine sample mass concentra-
tions (ng/cm2 of substrate area) for elements sodium and heavier. Nominal
uncertainties for the IEXE analyses were _+ 10 percent of the reported val-
ue, although values nearthe detection limit were less certain (+_ 30 percent).
In addition, the gold-coated substrates caused interferences which added to
the uncertainty of the measurements. The backup filters were not analyzed
because glass-fiber filters are incompatible with IEXE analysis.
Only one of the four impaction areas on each stage was analyzed. The
total mass of an element on an impactor stage was calculated using the equa-
tion
H f n A
M = — Am,
ct
where Mis the total mass of the element (ng), n is the number of impaction
areas on the stage (Table 7), A is the area scanned by the IEXE apparatus
(0.9 cm2), m is the elemental concentration (ng/cm ), and a is the fraction
of the impaction area contained in the scanned area. The greatest uncer-
tainty in the total mass calculation resulted from determination of the value
for a , because it was very difficult to ensure that the impaction area was at
the center of the area scanned by the IEXE system. In order to allow calcu-
lation of approximate total mass concentrations, the value of a was chosen
to be 0. 5 _+ 0. 25.
Mass concentrations corresponding to the total mass on an impactor
stage were calculated by dividing the mass by the air volume sampled. An
uncertainty of ±10 percent was assumed for the determination of sample air
volume.
An example of the results of an IEXE analysis is presented in Table
8. Several of the problems encountered with the elemental composition data
are illustrated in the table, specifically:
1 ) Signals from the gold-coated substrates tended to
"swamp" other elements;
2) Uncertainties increased for elemental masses on
the order of the minimum sensitivity;
3) Determination of total mass on an impactor stage
contributed as much error as the sample mass
measurements.
32
-------
TABLE 8. EXAMPLE OF ELEMENTAL COMPOSITION DATA
IMPACTOR STAGE C (3.0-0.4 Mm DIAMETER)
(2)
Element
Na
Mg
Al -
Si
S
Cl
K
Ca
Ti
V
Cr
Mn
Fc
Co
Ni
Cu
Zn
As
Se
Br
Rb
Sr
7.c
Mo
Da
Pt
Au
Hg
Pb
Minimum
Atomic Sensitivity
Number (ng/cm2)
11 187
12 117
13 139
14 143
16 170
17 105
19 64
20 40
22 48
23 40
24 44
25 41
26 41
27 39
28 43
29 36
30 76
33 1599
34 .315
35 210
37 265
38 141
40 190
42 303
56 -158
78 480
79 953
80 712
82 167
,3 > Total Mass On
Sample Mass Imp actor Stage
(ng/cm2) (ng)
206.5 + 81.0 1490 + 1330
(4)
96. 3 J; 26.4 ' 693 J; 540
146. 1 _+ 30.9 1050 jf 750
502. 3 _+ 67. 5 3620 _t 2300
y
104.3 + 20.8 751 jf 530
69. 2_+ 17.4 498 _+ 370
53. 4J; 16.6 384 _+ 310
99. 1 + 20.6
U)
39.9 _+ 14.0 287 jr 240
335.9^ 78.3 2420 + 1770
4021. Q+ 481.8
Mass
Concentration
(ng/m3)
676 jh 670
315J; 280
478 jj; 390
1640 _+ 1200
341 _+ 280
226 j 190
175J; 160
131 _+ 120
1100^ 910
(l ) Sample integrated over 16 plume traverses 3 km downwind of
Labadie Power Plant,
(2) Elements not reported
8/7/75
were not detected
(3) Sample mass values and uncertainties as reported by Crocker
Nuclear Laboratory.
(* ) Sample mass below minimum sensitivity of analysis.
33
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Interferences from gold-coated substrates are thought to be the most sig-
nificant source of error in the IEXE analysis, particularly because of the
possibility that some elements might have been masked completely by the
gold. In addition, it is possible that some of the signals identified as being
caused by other elements were actually spuriously generated by the gold.
Summary of Measurement Errors
The major sources of error in the elemental composition data are
listed in Table 9, along with methods for reducing the errors in the future.
The most serious errors were caused by optimization of the system for mi-
croscopic analysis, although significant errors were caused by inexperience
with the system. It should be noted that the airborne impactor system was
developed for the 1975 MISTT program, and experience gained during the
program has led to the development of more accurate sampling techniques.
Specifically, flight plans involving orbits in the plume for sample collection
have provided representative plume samples with sufficient mass for accu-
rate analysis. In addition, techniques have been developed that allow a more
precise positioning of samples in the IEXE apparatus. These techniques
have reduced the error in the calculation of totalmass on an impactor stage
from 50 percent or more to about 10 percent.
ANALYSIS
Sampling Summary
Four types of impactor samples were collected: power plant plume,
urban plume, background, and regional. Power plant plume samples were
collected in the plume of the coal-fired Labadie power plant. This plant,
located about 55 km west of the St. Louis Gateway Arch, is rated at 2250
MW gross generating capacity.
Urban plume samples were collected downwind of St. Louis, Missouri.
The plume from the industrial/refinery complex at Wood River, Illinois (just
across the Mississippi River from St. Louis) was usually imbedded in the
St. Louis plume, and was considered to be part of the urban plume.
Background impactor samples were collected in conjunction with ur-
ban and power plant plume samples. These samples were collected so that
the contribution of the background to plume pollutant concentrations could be
determined.
On 1 0 August 1 975, a special flight plan was usedto study the horizontal
and vertical distribution of pollutants between Kansas City, Missouri, and
Indianapolis, Indiana. This regional sampling took place during stagnant,
low-visibility meteorological conditions over much of the sampling area.
34
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TABLE 9.
SUMMARY OF SIGNIFICANT MEASUREMENT ERRORS
Approx.
Magnitude
Source of Error (Percent)
Particle bounce-off Unknown
or reentrainment
Non-isokinetic 10
sampling
Use of glass-fiber
filters, which pre-
vented IEXE analysis
Spurious signal Unknown
generation by gold
Masking of real Unknown
signals by gold
Uncertainties in 10-30
IEXE analysis
system
Inaccurate position- 50
ing of sample in
IEXE apparatus
Flow Measurement 10
Inclusion of back- 30
ground air in plume
samples
NOTES: a) Magnitudes of errors
b) Errors with unknown
most serious sources
Method for Improvement
Coat substrates with a collec-
tion grease
Higher- re solution flow mea-
surements
Use Nuclepore or paper filters
Do not use gold-coated sub-
strates
Do not use go Id- coated sub-
strates
Longer sample collection
times
More precise positioning of
samples in IEXE apparatus
Higher- resolution flow
me a s ur ement
Collect plume samples only
while in plume
generally are rough estimates
magnitudes are believed to be
of uncertainty
35
-------
A summary of the impactor samples is given in Table 10.
Elemental Composition of Aerosol Samples
Recognizing that measurement errors make quantitative analyses of
the impactor data highly unreliable, the analytical effort was directed towards
qualitatively understanding the elemental composition of the aerosol sam-
ples. No attempt was made to analyze the change in chemical composition
with particle size because of the large potential for particle bounce due to
the ungreased substrates. Because the aerosols of primary interest to
Project MISTT are those in the accumulation mode (generally 0. 1-2 Mm di-
ameter), only data from stage C of the impactors (0. 4-3 jim diameter) were
evaluated.
Before discussing the characteristics of the elemental composition of
the aerosol samples, it is important to reiterate the limitations of the data.
The size interval covered by stage C is predicted by theory to be 0.4-3.0
H m diameter. The impactor was not calibrated for this program, and the
actual interval might be different. In addition, this stage probably collected
some particles larger than 3. 0 pm as a result of particle bounce from the
larger stage. Another major limitation of the data is the interference caused
by the gold coating on the substrates. Although the effects of the interfer-
ence are not known, it is possible that signals from some elements were
masked and others enhanced by the gold. No corrections for these effects
could be applied to the data.
The average elemental composition of the four types of aerosol sam-
ples collected during the program is depicted in Figure 9. Average compo-
sition for each category was calculated by summing the mass of each ele-
ment on all impactors in the category to determine total elemental mass.
Elemental masses less than the detection limit of the IEXE system were not
included in the sum. Total detected sample mass was calculated by sum-
ming the total elemental masses for elements with atomic masses between
Na and Fe (inclusively). The average contribution of each element (percent
of total detected mass) was found by dividing total elemental mass by total
detected sample mass.
This method of presenting the data was chosen because it does not in-
clude the errors involved in calculating mass concentrations discussed ear-
lier. The drawback to such a presentation is that differences between the
distributions can be masked or enhanced by differences in total mass con-
centrations. For example, an element uniformly distributed in the atmo-
sphere would comprise different portions of the total sample mass for each
category even though its mass concentration was constant. This bias in pre-
sentation was unavoidable because of the large errors involved in calculating
36
-------
TABLE 10. IMP AC TOR SAMPLING SUMMARY
Date (1975)
July 17
July 18
July 24-25
July 28
July 29-30
August 6
August 7-8
August 8-9
August 10
August 1 1
August 12
August 1 3
Time (CDT)
0730-1330
0700-1900
2115-0430
1315-1800
1330-1130
1700-1930
1730-0115
2215-0145
0515-1745
0745-2130
0800-1515
0645-1100
Mission
Emphasis
Urban
Urban
Labadie
Urban
Urban
Labadie
Labadie
Labadie
Regional
Urban
Urban
Labadie
Number of Samples
Power Plant Urban
Plume Plume Regional
4
4
4
3
8
2
6
3
4
3
4
4
TOTAL 19 26 4
Background
--
--
1
1
--
1
1
1
--
3
--
2
10
OJ
-------
100
90
80
70
60
50
40
30
20
10
Power Plant Urban
Plume Plume
K (3%)
Al (3%)
Mg (3%)
Ti (3%)
Na (4%)
P (5%)
V (5%)
Cl (11%)
S (30%)
Si (31%)
90
80
70
60
50
40
30
20
10
0
P (4%)
Fe (47.)
Cl (5%)
Si (11%)
S (66%)
100
90
80
70
60
50
40
30
20
10
Backgroun
Mg (5%)
Fe (7%)
Na (7%)
Al (7%)
Cl (9%)
S (24%)
Si (34%)
d
100
90
80
70
60
50
40
30
20
10
0
Regional
Sampling
P (3%)
Si (3%)
Fe (4%)
Cl (7%)
S (81%)
Figure 9. Elemental composition of aerosol samples (0. 4-3. 0 Mm dia).
Reported values are averages for all samples collected on
gold-coated Nuclepore substrates. Only elements with atomic
masses between Na and Fe (inclusively) are included in total.
Elements comprising two percent or less of the total mass
are not listed.
38
-------
mass concentrations. For future studies, a more representative presenta-
tion would be to scale the height of each column in Figure 9 by the,.average
mass concentration for that category.
One obvious feature of the distributions in Figure 9 is the predomi-
nance of sulfur. The fact that sulfur is a major species in all four types of
samples indicates that it is widely distributed in the atmosphere, and thus
must be considered a regional as well as a local-source pollutant. However,
the abundance of sulfur in the regional sampling data is somewhat surpris-
ing, because intuitively the expected composition should be similar to that
for the background samples. One explanation for the pronounced difference
is that the background distribution is an average covering several days with
varying meteorology, while the regional samples were collected over a time
period of about 12 hours in a very hazy air mass. The regional samples may
be indicative of the dominant role played by sulfur in visibility reduction in
large-scale hazy air masses. This subject is discussed further by Husar
et al (15).
The similarity between the power plant plume and background sample
composition is probably a result of the manner in which samples were col-
lected. Because a large amount of background air is sampled during plume
traverses, the two types of samples should be similar. The effects of the
power plant plume can be observed in the data, because such typical plume
constituents as vanadium, titanium, and potassium were observed in signif-
icant quantities (> 2 percent of total mass) only in the power plant plume
samples.
The other major elements in the aerosol composition, silicon and
chlorine, are primarily of natural origin. Although silicon is a common el-
ement in power plant plumes, its primary origin is soil. One possible ori-
gin of the chlorine is sea salt advected into the area from the Gulf of Mexi-
co.
One element that was not detected in the urban samples (and that might
be expected to be present) is lead, a major component of automobile ex-
haust. However, work byFlocchini et al (14) indicated that most of the lead
in urban aerosols is present in the 0.6 pm diameter and smaller size range.
This could be the reason for the lack of lead in the St. Louis urban plume
samples, although this hypothesis would require analysis of the backup fil-
ters for confirmation.
Two aspects of the elemental composition data that were unexpected,
and for which no plausible explanations could be found, are the lack of iron
in the power plant plume samples and the lack of calcium in all samples.
Although these elements were present in small quantities (< 2 percent of
39
-------
total mass), a substantially greater percentage was expected. Coal-fired
power plants are generally considered to be major sources of iron, and their
plumes should contain significant amounts of that element. Likewise, cal-
cium is a primary constituent of the earth's crust, and should have appeared
in the aerosol samples. Further work is needed to determine if the absence
of these elements is significant or an artifact of the sampling and analysis
methods.
40
-------
REFERENCES
1. White, W.H. , J. A. Anderson, W.R. Knuth, D. L. .Blumenthal, J. C.
Hsiung and R. B. Husar, 1976. Midwest Interstate Sulfur Transfor-
mation and Transport Project: Aerial Measurements of Urban and
Power Plant Plumes, Summer 1974. EPA-600/3-76-11 0.
2. White, W.H. , J. A. Anderson, D. L. Blumenthal, R. B. Husar, N. V.
Gillani, J. D. Husar, andW.E. Wilson, Jr. 1976. Formation and
Transport of Secondary Air Pollutants: Ozone and Aerosols in the St.
Louis Urban Plume. Science. 194:187-189.
3. White, W. H. , D. L. Blumenthal, J. A. Anderson, R. B. Husar,
and W. E. Wilson, Jr. 1977. Ozone Formation in the St. Louis Ur-
ban Plume. International Conference on Photochemical Oxidant Pol-
lution and Its Control Proceedings. EPA-600/3-7-001a, p. 237.
4. White, W.H. , J. A. Anderson, D. L. Blumenthal, R. B. Husar, N. V.
Gillani, S.B. Fuller, K.T. Whitby, and W.E. Wilson, Jr. 1976. For-
mation of Ozone and Light-Scattering Aerosols in the St. Louis Urban
Plume. 171st National American Chemical Society Meeting. New York,
New York. April. In: Proceedings of the Division of Environmental
Chemistry.
5. White, W.H. , D. L. Blumenthal, J. A. Anderson, R. B. Husar, and
W. E. Wilson, Jr. 1976. Formation and Transport of Light-Scattering
Aerosols in the St. Louis Urban Plume. Symposium on Radiation in
the Atmosphere. Garmisch-Partenkirchen, Germany. August. (Pro-
ceedings to be issued. )
6. Blumenthal, D. L. , and W. H. White., 1977. Transport of Oxidant and
Oxidant Precursors . 5th National Symposium of the Air Pollution Con-
trol Division of The American Society of Mechanical Engineers. Pitts-
burgh, Pennsylvania. May 11-12.
7. Wilson, W. E. 1977. Midwest Interstate Sulfur Transformation and
Transport Study (MISTT): Summary. International Symposium on Sul-
fur in the Atmosphere. Dubrovnik, Yugoslavia. September. (Proceed-
ings to be published in Atmospheric Environment)
41
-------
8. Husar, R. B. , J. D. Husar, N. V. Gillani, S.B. Fuller, W.H. White,
J. A. Anderson, W. M. Vaughn, andW.E. Wilson, Jr. 1976. Pollu-
tant Flow Rate Measurement in Large Plumes: Sulfur Budget in Pow-
er Plant and Area Source Plumes in the St. Louis Region. 1 71st Na-
tional American Chemical Society Meeting. New York, New York.
April. In: Proceedings of the Division of Environmental Chemistry.
9. Durham, J. L. , W.E. Wilson, V. P. Aneja, J. H. Overton, Jr., D. L.
Blumenthal, J. A. Anderson, S. Frisella, W. Dannevik, L. Hull, and
R. Woodford. 1977. Sulfate Aerosol Formation Rate in an Oil-Fired
Power Plant Plume. 83rd National Meeting of the American Institute
of Chemical Engineers. Houston, Texas. March 20-24.
/ V
10. Markson, R. , D. L. Blumenthal, and J. Sedlacek. 1977. Atmospheric
Electrical Plume Detection: Theory and Field Measurements. Ameri-
can Nuclear Society Topical Symposium. Aerial Techniques for Envi-
ronmental Monitoring. Las Vegas, Nevada. March 7-11.
11. Anderson, J. A. , et al. 1976. Vol. I: Sampling Summary: Aircraft
Monitoring Support for an Aerosol Characterization Study in St. Louis
--1975 Program. Vol. II: 1975 MISTT Data Volume. MRI Report 76
FR-1417.
12. Anderson, J. A., et al. 1977. Airborne Measurements in Oil-Fired
Power Plant Plume--Tampa Study. MRI Report 77-FR-1491.
13. Draftz, R. G. , J.Graf, and G. Yamate. 1976. Microscopical Analy-
sis of Aerosols Transported from St. Louis. 171st National American
Chemical Society Meeting. New York. New York. April. In: Pro-
ceedings of the Division of Environmental Chemistry.
14. Flocchini, R. G. , T. A. Cahill, D. J. Shodoan, S. J. Lange, R. A.
Eldred, P. J. Feeney, G.W. Wolfe, D. C. Simmcroth, J. K. Suder.
1976. Monitoring California's Aerosols by Size and Elemental Compo-
sition. Environmental Science and Technology. 10(l):76-82.
15. Husar, R. B. , N.V. Gillani, J. D. Husar, C. C. Paley, P.N. Turcu.
Long Range Transport of Pollutants Observed Through Visibility Con-
tour Maps, Weather Maps and Trajectory Analysis. 3rd Symposium
on Atmospheric Turbulence, Diffusion and Air Quality. American Me-
teorological Society. Raleigh, North Carolina. October.
42
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PROJECT MISTT BIBLIOGRAPHY
PUBLICATIONS
Bower, Kide (J. R. Brock). A Method of Modelling Chemically Re-
active Plumes. M.S. Thesis. University of Texas, Austin,
Texas. August, 1976.
Chatfield, R. , and R. A. Rasmussen. 1977. An Assessment of the
Continental Lower Tropospheric Ozone Budget. Internationa 1
Conference on Photochemical Oxidant Pollution and Its Control
Proceedings. EPA-600/3-7-OOla, p. 121.
Cunningham, P. T. , and S. A. Johnson. 1976. Spectroscopic Obser-
vation of Acid Sulfate in Atmospheric Particulate Samples.
Science. 191:77-79.
Fondario, D. A. (W. E. Wilson and H. Jeffries). An Analysis of a
High Sulfate Episode at Wheeling, West Virginia. M.S. Thesis.
University of North Carolina. August 1976.
Husar, J. D., R. B. Husar, and P. K. Stubits. 1975. Determin-
ation of Submicrogram Amounts of Atmospheric Particulate
Sulfur. Anal. Chemistry. 47:2062.
§Husar, J. D. , R. B. Husar, E. S. Macias, W^ E. Wilson, Jr.,
J. L. Durham, W. K. Shepherd, and J. A. Anderson. 1976.
Particulate Sulfur Analysis : Application to High Time-Resolu-
tion Aircraft Sampling in Plumes. Atmospheric Environment.
J_0:591-595.
Husar, R. B. 1976. Thermal Analysis of Aerosols. J. Thermal Anal.
10:2.
§ - Denotes analyses of MRI aircraft data collected as part of the field
programs described herein (Summer 1975, February 1 976, Feb-
ruary 1977).
43
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Husar, R. B., D. E. Patterson, C. C. Paley, N. V. Gillani. Ozone
in Hazy Air Masses. 1977. International Conference on Photo-
chemical Oxidant Pollution and Its Control Proceedings. EPA-
600/3-7-OOla, p. 275.
Rasmussen, R. A., and R. Chatfield. 1977. Hydrocarbon and Oxi-
dant Chemistry Observed at a Site Near St. Louis. EPA-600/
000.
Wesely, M. L. , B. B. Hicks, W. P. Dannevik, S. Frisella, and
R. B. Husar. An Eddy-Correlation Measurement of Particulate
Deposition from the Atmosphere. Submitted to: Atmospheric
En vi r onment.
Whitby, K. T. , B. K. Cantrell, R. B. Husar, N. V. Gillani, J.A.
Anderson, D. L. Blumenthal, W. E. Wilson, Jr. Aerosol For-
mation in a Coal-Fired Power Plant Plume. Submitted to: At-
mospheric Environment.
White, W. H., J. A. Anderson, W. R. Knuth, D. L. Blumenthal,
J. C. Hsiung and R. B. Husar. 1976. Midwest Interstate Sulfur
Transformation and Transport Project: Aerial Measurements
of Urban and Power Plant Plumes, Summer 1974. EPA-600/
3-76-110.
§ White, W.H., J. A. Anderson, D. L. Blumenthal, R. B. Husar,
N. V. Gillani, J. D. Husar, and W. E. Wilson, Jr. 1976. For-
mation and Transport of Secondary Air Pollutants: Ozone and
Aerosols in the St. Louis Urban Plume. Science. 194:187-1 89.
§White, W. H. , D. L. Blumenthal, J. A. Anderson, R. B. Husar,
and W. E. Wilson, Jr. 1977. Ozone Formation in the St. Louis
Urban Plume. International Conference on Photochemical Oxi-
dant Pollution and Its Control Proceedings. EPA-600/3-7-001a.
p. 237.
§White, W. H. NOX -O3 Photochemistry in Power Plant Plumes:
Comparison of Theory with Observation. Environ. Sci. &
Technol., 11:10,, pp. 995-1000.
§ - Denotes analyses of MRI aircraft data collected as part of the field
programs described herein (Summer 1975, February 1 976, Feb-
ruary 1977).
44
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§ Wilson, W.E., Jr., R. J. Charlson, R. B. Husar, K. T. Whitby,
and D. L. Blumenthal. 1977. Sulfates in the Atmosphere: A Pro-
gress Report on Project MISTT. EPA-600/7-77-021.
§ Wilson, W.E. , Jr., 1977. Sulfate Formation in Power Plant Plumes:
A Critical Reveiew. EPA-600/000.
PRESENTATIONS
1973 Annual Meeting of the Air Pollution Control Association Pa-
cific Northwest International Section. Seattle, Washington. Novem-
ber 1973.
Blumenthal, D. L. Measurement of Physical and Chemical Plume
Parameters Using an Airborne Monitoring System.
Division of Environmental Chemistry American Chemical Society.
Los Angeles, California. March-April 1974.
Husar, R. B. , D. L. Blumenthal, J. A. Anderson, and W. E. Wil-
son, Jr. The Urban Plume of St. Louis.
68th Annual Meeting, Air Pollution Control Association. Boston.
Massachusetts. June 1975.
Vaughn, W. M. , R. Sperling, N. V. Gillani, and R. B. Husar. Hori-
zontal SO« Mass Flow Rate Measurements in Plumes: A Com-
parison of Correlation Spectrometer Data with a Dispersion and
Removal Model.
White, W.H. , and D. L. Blumenthal. The Stability and Long Range
Transport of Ozone or Ozone Precursors.
§ - Denotes analyses of MRI aircraft data collected as part of the field
programs described herein (Summer 1 975, February 1 976, Feb-
ruary 1977).
45
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International Symposium on the Development of Nuclear-based Tech-
niques for the Measurement, Detection, and Control of Environmen-
tal Pollutants. March 15-19, 1976. Vienna, Austria.
Cunningham, P. T. , and B. D. Holt. Stable Isotope Ratio Measure-
ments in Atmospheric Sulfate Studies.
171st National American Chemical Society Meeting. New York, New
York. April 1976. In; Proceedings of the Division of Environmental
Chemistry.
§Draftz, R. G., J. Graf, and G. Yamate. Microscopical Analysis of
Aerosols Transported from St. Louis.
Draftz, R. G. , and J. Graf. Microscopical Analysis of St. Louis
TSP.
§Husar, R. B. , J. D. Husar, N. V. Gillani, S. B. Fuller, W.H.
White, J. A. Anderson, W. M. Vaughan, and W. E. Wilson, Jr.
Pollutant Flow Rate Measurement in Large Plumes: Sulfur Bud-
get in Power Plant and Area Source Plumes in the St. Louis
Region.
Whitby, K. T. , B. K. Cantrell, R. B. Husar, N. V. Gillani, J. A.
Anderson', D. L. Blumenthal, and W. E. Wilson, Jr. Aerosol
Formation in a Coal-Fired Power Plant Plume.
0
§ White, W. H. , J. A. Anderson, D. L. Blumenthal, R. B. Husar,
N. V. Gillani, S. B. Fuller, K. T. Whitby, and W. E. Wilson,
Jr. Formation of Ozone and Light-Scattering Aerosols in the St.
Louis Urban Plume.
§ Wilson, W. E. , Jr. , R. B. Husar, W. H. White, K. T. Whitby, D. B.
Kittleson. Chemical Reactions in Power Plant Plumes.
- Denotes analyses of MRI aircraft data collected as part of the field
programs described herein (Summer 1975, February 1976, Feb-
ruary 1977).
46
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69th Annual Meeting. Air Pollution Control Association. Portland,
Oregon. June 1976.
§Draftz, R. G. Aircraft Collection and Microscopical Analyses of
Ambient Aerosols from Urban Atmospheres.
§Wilson, W. E. , Jr., R. J. Charlson, R. B. Husar, K. T. Whitby,
D. Li. Blumenthal. Sulfates in the Atmosphere.
Symposium on Radiation in the Atmosphere. Garmisch-Partenkirchen,
Germany. August 1976. (Proceedings to be issued)
Husar, R. B. Determination of Ambient H2SO4 and its Ammonium
Salts by in-situ Aerosol Thermal Analysis.
Husar, R. B. , N. V. Gillani, J. D. Husar, C. C. Paley. Large
Scale Haziness over Midwestern and Eastern United States.
§White, W. H. , D. L. Blumenthal, J. A. Anderson, R. B. Husar, and
W. E.Wilson, Jr. Formation and Transport of Light-Scatter ing
Aerosols in the St. Louis Urban Plume.
International Conference on Stable Isotopes. August 4-6.1976. Low-
er Hutt, New Zealand.
Holt, B.D. , P. T. Cunningham, and A. G. Engelkemeir. Application
of Oxygen-18 Analysis to the Study of Atmospheric Sulfate For-
mation. In Press.
Symposium on Aerosol Science and Technology. 82nd National Meet-
ing of American Institute of Chemical Engineers. Atlantic City, New
Jersey. September 1976.
§Husar, R. B. , N. V. Gillani, and J. D. Husar. Particulate Sulfur
Formation in Power Plant, Urban and Regional Plumes.
§Whitby, K. T. , and B. K. Cantrell. Size Distribution and Concen-
tration of Atmospheric Aerosol.
§ - Denotes analyses of MRI aircraft data collected as part of the field
programs described herein (Summer 1 975, February 1 976, Feb-
ruary 1977).
47
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NATO/CCMS 7th Technical Meeting on Air Pollution Modeling and its
Applications. Airlie, Virginia. September 1976. (Proceedings to be
issued).
Gillani, N. V. , and R. B. Husar. Analytical-Numerical Model for
Mesoscale Transport, Transformation and Removal of Air Pol-
lutant s.
Husar, R. B., N. V. Gillani, J. D. Husar. A Study of Long Range
Transport from Visibility Observations, Trajectory Analysis and
Local Air Pollution Monitoring Data.
Overton, J. H. , B. K. Lamb, and F. H. Shair. A Dual Tracer Study
for Validation of Models with Respect to High and Low Altitude
Sources.
3rd Symposium on AtmosphericTurbulence. Diffusion and Air Qual-
ity. American Meteorological Society. Raleigh, North Carolina.
October 1976.
Dannevik, S. , S. Frisella, L. Granat, and R. B. Husar. SOj Depo-
sition Measurements in the St. Louis Region.
Gillani, N. V. , and R. B. Husar. Mesoscale Model for Pollutant
Transport, Transformation and Ground Removal.
Husar, R. B. , N. V. Gillani, J. D. Husar, C. C. Paley, P. N.
Turcu. Long Range Transport of Pollutants Observed Through
Visibility Contour Maps, Weather Maps and Trajectory Analysis.
§Wilson, W. E., Jr., R. B. Husar, N. V. Gillani, S. B. Fuller,
W. H. White, J. A. Anderson, and D. L. Blumenthal. Charac-
terization of Urban Plumes.
Non-Urban Tropospheric Composition Symposium. Miami Beach.
Florida. November 10-12. 1976.
Rasmussen, R. A., R. B. Chatfield, and M. W. Holden. Transport
of Hydrocarbon and Oxidant Chemistries Observed at a Rural
Mid-West Site.
§ - Denotes analyses of MRI aircraft data collected as part of the field
programs described herein (Summer 1 975, February 1 976, Feb-
ruary 1977).
48
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4th National Conference on Fire and Forest Meteorology. Society of
American Foresters/American Meteorology Society. St. Louis.
Missouri. November 1976. (Proceedings to be issued).
Gillani, N. V. , and R. B. Husar. Synoptic Haziness Over the Eastern
United States and Its Long Range Transport.
American Nuclear Society Topical Symposium. AerialTechniques for
Environmental Monitoring. Las Vegas, Nevada. March 7-11, 1977.
Markson, R. , D. L. Blumenthal, and J. Sedlacek. Atmospheric
Electrical Plume Detection: Theory and Field Measurements.
83rd National Meeting of the American Institute of Chemical Engi-
neers. Houston. Texas. March 20-24, 1977.
§Durham, J. L. , W. E. Wilson, V. P. Aneja, J. H. Overton, Jr.,
D. L. Blumenthal, J. A. Anderson, S. Frisella, W. Dannevik, L.
Hull, and R. Woodford. Sulfate Aerosol Formation Rate in an
Oil-Fired Power Plant Plume.
5th National Symposium of the Air Pollution Control Division of The
American Society of Mechanical Engineers. Pittsburgh, Pennsylva-
nia. May 11-12. 1977.
§Blumenthal, D. L. , and W. H. White. Transport of Oxidant and Oxi-
dant Precursors.
International Symposium on Sulfur in the Atmosphere. Dubrovnik,
Yugoslavia. September 1977. (Proceedings to be published in Atmo-
pheric Environment)
Invited Papers -
Charlson, R. J. Chemical Properties of Sulfur Aerosols.
Husar, R. B. Project MISTT - Sulfur Budget in Large Plumes.
§ - Denotes analyses of MRI aircraft data collected as part of the field
programs described herein (Summer 1975, February 1 976, Feb-
ruary 1977).
49
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International Symposium on Sulfur in the Atmosphere. Dubrovnik,
Yugoslavia. September 1977. (Proceedings to be published in Atmo-
spheric Environment. (Continued)
Invited Papers (Continued)
§ Wilson, W.E. Midwest Interstate Sulfur Transformation and Trans -
port Study (MISTT): Summary.
Contributed Papers -
§Blumenthal, D. L. , J. A. Ogren, and J. A. Anderson. Airborne
Sampling System for Project MISTT.
Cobourn, G. , R. B. Husar, J. D. Husar. Monitoring of Ambient
H_SO4andits Ammonium Salts byin-situ Aerosol Thermal Anal-
ysis.
Cantrell, B. K. , and K. T. Whitby. Aerosol Size Distributions
and Aerosol Volume Formation Rates for Coal-Fired Power
Plants.
Gillani, N. V., R. B. Husar, J. D. Husar, D. E. Patterson. Pro-
ject MISTT: Kinetics of Particulate Sulfur Formation in a
Power Plant Plume out to 300 km.
Gillani, N. V. Project MISTT: Mesoscale Plume Modeling of the
Dispersion, Transformation, and Ground Removal of SO2«
Kittelson, D. B. , M. Veermersch, B.Y.H. Liu, D. Y. H. Pui, K. T.
Whitby, and R. L. McKenzie. Total Sulfur Aerosol Detection
with an Electrostatically Pulsed Flame Photometric Detector
System.
Leslie, A. C. D. , M. S. Ahlberg, J. R. Winchester, and J. W. Nel-
son. Aerosol Characterization for Sulfur Oxide Health Effects
Assessment.
Liu, B.Y.H. , D.Y.H. Pui, K. T. Kittelson, D. B. Kousaka.Y.
Kousaka,and R. L. McKenzie. The Aerosol Mobility Chromato-
graph: A New Detector for Sulfuric Acid Aerosols.
§ - Denotes analyses of MRI aircraft data collected as part of the field
programs described herein (Summer 1 975, February 1976, Feb-
ruary 1977).
50
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International Symposium on Sulfur in the Atmosphere. Dubrovnik,
Yugoslavia. September 1977. (Proceedings to be published in Atmo-
spheric Environment. (Continued)
Contributed Papers (Continued) -
Lyons, W. A. , E. M. Rubin, K. T. Whitby. Satellite Detection of
Long Range Pollution Transport and Sulfate Aerosol Hazes.
Smith, T.B., D. L. Blumenthal, J. A. Anderson, A.H. Vanderpol,
and R. B. Husar. Long Range Transport of SCL in Power Plant
Plumes: Day and Night.
Whitby, K. T., B. K. Cantrell, D. B. Kittelson. Nuclei Formation
Rates in a Coal-Fired Power Plant Plume.
MRI DATA VOLUMES
Anderson, J.A., et al. 1976. Vol. I: Sampling Summary: Air-
craft Monitoring Support for an Aerosol Characterization Study
in St. Louis-1975 Program. Vol. II: 1975 MISTT Data Volume.
MRI Report 76 FR-1417.
Anderson, J.A., et al. 1977. Airborne Measurements in Oil-Fired
Power Plant Plume--Tampa Study. MRI Report 77 FR-1491.
White, W. H. , J. A. Anderson, et al. 1975. Summary Report-
Aircraft Monitoring Support for an Aerosol Characterization
Study in St. Louis. MRI Report 75 FR-1335.
§ - Denotes analyses of MRI aircraft data collectedas part of the field
programs described herein (Summer 1975, February 1976, Feb-
ruary 1977).
51
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APPENDIX A
AIRBORNE SAMPLING SYSTEM FOR PROJECT MISTT
The measurement system installed on the Cessna 206 in the summer of
1976 is described in a paper entitled "Airborne Sampling System for
Plume Monitoring", prepared for presentation at the International Sym-
posium on Sulfur, September 7-14, 1977, Dubrovnik, Yugoslavia, to
appear in Atmospheric Environment, January, 1978. The system on
the aircraft in 1975,and in the winters of 1976 and 1977, was identical,
with only minor exceptions :
1) The hydrocarbon/halocarbon sample collec-
tion system was not installed in 1975;
2) The stripchart recorder was not installed in
1975;
3) The venturi exhaust was used as the vacuum
source for the sulfate sampler in 1975;
4) The optical particle counter electronics were
mounted on the floor just aft of the electrical
aerosol analyzer in 1975;
5) The impactor system and size distribution
measurement system were not installed dur-
ing the February 1976 sampling program at
the Moss Landing power plant;
6) An ultraviolet photometer was installed on
the aircraft for the February 1977 sampling
program.
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/7-78-041
TITLE AND SUBTITLE POLLUTANT MEASUREMENTS IN PLUMES FROM
POWER PLANTS AND CITIES
Summer 1975, February 1976, and February 1977
A Project MISTT Report
3. RECIPIENT'S ACCESSIOI*NO.
5. REPORT DATE
March 1978
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S) •
8. PERFORMING ORGANIZATION REPORT NO.
J. A. Ogren, D. L. Blumenthal, J. A. Anderson
and W. H. White
MRI 77 FR-1511
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Meteorology Research, Inc.
464 West Woodbury Road
Altadena, California 91001
10. PROGRAM ELEMENT NO.
INE625 EA-07 (FY-77)
11. CONTRACT/GRANT NO.
68-02-2245
12. SPONSORING AGENCY NAME AND ADDRESS
Environmental Sciences Research Laboratory - RTP, NC
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Final fi/1R/7R-in/1R/77
14. SPONSORING AGENCY CODE '
EPA/600/09
15. SUPPLEMENTARY NOTES
i. ABSTRACT
[Airborne measurements of aerosols and polluted gases in urban and power plant
plumes-were conducted during the summer of 1975, February 1976, and February 1977
in the vicinity of St. Louis, Missouri; Moss Landing, California; and, Clearwater,
Florida, respectively. The principal objective was to characterize the physical
and chemical behavior of these plumes under a variety of meteorological conditions,
with emphasis on sulfur transport and transformation.I Results illustrate the
regional nature of air pollution. The transport of well-defined urban, plumes
over 150 km downwind of a city was documented during day and night conditions.
Power plant plumes were sampled over 100 km downwind of the source at night and
during the day over the ocean; strong dilution mechanisms limited the sampling
of power plant plumes to 40 km during the day over land. Measurements indicated
that, when the plume was not well mixed to the ground, the mass flux of sulfur in
the plume did not change with distance. In urban plumes, a significant reduction
in sulfur was found; only about one-third of the emissions were transported beyond
100 km downwind of the city.
New techniques used in this study included an airborne impactors system for
aerosol collection and atmospheric electrical measurements for plume tracting.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
* Air pollution
* Aerosols
* Sulfates
* Sulfur dioxide
* Sulfuric acid
Electric power plants
* Plumes
* Conversion
* Measurement
Airplanes
b.lDENTIFIERS/OPEN ENDED TERMS
Project MISTT
c. COSATl Field/Group
13B
07D
07B
10B
21B
8. DISTRIBUTION STATEMENT
RELEASE TO PUBLIC
19. SECURITY CLASS (This Report)
UNCLASSIFIED
21. NO. OF PAGES
20. SECURITY CLASS (Thispage)
UNCI ASSTFTFn
22. PRICE
EPA Form 2220-1 (9-73)
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