United States
Environmental Protection
Agency
Office of Air Quality EPA454/R-95-014
Planning and Standards October 1995
Research Triangle Park NC 27711
Air
<> EPA National Air Quality and
Emissions Trends Report,
1994
-------
454/R-95-014
National Air Quality and
Emissions Trends Report,
1994
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Emissions Monitoring and Analysis Division
Air Quality Trends Analysis Group
Research Triangle Park, North Carolina 2771 1
November
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, J 994
-------
Disclaimer
This report has been reviewed and approved for publication by the U.S. Environmental Protection Agency's Office
of Air Quality Planning and Standards. Mention of trade names or commercial products are not intended to
constitute endorsement of recommendation for use.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Preface
This is the twenty-second annual report on air pollution trends in the United States issued by the Environmental
Protection Agency. The report is prepared by the Air Quality Trends Analysis Group (AQTAG) in Research
Triangle Park, North Carolina and is directed toward both the technical air pollution audience and other interested
parties and individuals. AQTAG solicits comments on this report and welcomes suggestions regarding techniques,
interpretations, conclusions, or methods of presentation. Please forward any response to the Trends Team, (MD-
14) U.S. Environmental Protection Agency, Air Quality Trends Analysis Group, Research Triangle Park, North
Carolina, 27711.
Readers of previous reports should note the following changes:
An expanded appendix including:
- All statistical data tables.
- A discussion of methodology.
* Graphics displaying the 10 and 20 year air quality trends in urban, suburban, and rural locales.
Additional air quality trends statistical summaries.
Additional categories in the pollutant emissions tables.
For additional air quality data, readers can access the Aerometric Information Retrieval System's (AIRS) executive
software from the AIRS bulletin board on the Office of Air Quality Planning and Standards' (OAQPS) Technology
Transfer Network (TTN). Electronic copies of trends graphics and Lotus 1-2-3 spreadsheets can be obtained from
the Ambient Monitoring Technology Information Center (AMTIC) bulletin board system of the TTN. To gain
access by modem, dial (919) 541-5742. Internet users can access EPA's homepage at:
(http://www.epa.gov/docs/oar/oarhome.html), or the TTN at the following telnet address: (ttnbbs.rtpnc.epa.gov).
For help in accessing the OAQPS's TTN, dial (919) 541-5384.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Contents
Chapter 1: Executive Summary 1-1
Chapter 2: Air Quality Trends 2-1
Carbon Monoxide 2-3
Lead 2-6
Nitrogen Dioxide - 2-9
Ozone 2-12
Particulate Matter 2-16
Sulfur Dioxide 2-19
Visibility 2-22
References 2-24
Chapter 3: PAMS: Enhanced Ozone and Precursor Monitoring 3-1
Chapter 4; Air Toxics 4-1
Emission Trends 4-1
Background and Further Details 4-2
Air Toxics Regulation and Implementation Status 4-6
References 4-10
Chapter 5: Nonattainment Areas 5-1
Chapter 6: Selected Metropolitan Area Trends 6-1
The Pollutant Standards Index 6-1
References 6-4
Chapter 7: International Air Pollution Perspective 7-1
Emissions 7-1
Ambient Air 7-4
References 7-6
Appendix A: Data Tables A^l
Appendix B: Methodology B-l
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Figures
Figure 1-1: Summary of emissions changes for all sixNAAQS pollutants between 1970 and 1994. 1-2
Figure 1-2: Total U.S. population, 1970-1994. 1-2
Figure 1-3: Total U.S. vehicle miles traveled, 1970-1994. 1-4
Figure 1-4: Total U.S. Gross Domestic Product, 1970-1994. 1-4
Figure 1-5: Number of people living in counties with air quality levels above the NAAQS in 1994. 1-5
Figure 2-1: Trend in second maximum non-overlapping 8-hour average CO concentrations, 1985-1994. 2-5
Figure 2-2: National total CO emissions trend, 1985-1994. 2-5
Figure 2-3: CO second maximum 8-hour concentration trends by location, 1985-1994. 2-5
Figure 2-4: Highest CO second maximum 8-hour concentration by county, 1994. 2-6
Figure 2-5: CO emissions by source category, 1994. 2-7
Figure 2-6: Long-term ambient CO trend, 1975-1994. 2-7
Figure 2-7: Trend in maximum quarterly average Pb concentrations, 1985-1994. 2-8
Figure 2-8: National total Pb emissions trend, 1985-1994. 2-8
Figure 2-9: Pb maximum quarterly mean concentration trends by location, 1985-1994. 2-11
Figure 2-10: Maximum quarterly Pb concentrations in the vicinity of Pb point sources. 2-11
Figure 2-11: Highest Pb maximum quarterly mean concentration by county, 1994. 2-12
Figure 2-12: Pb emissions by source category. 2-12
Figure 2-13: Long-term ambient Pb trend, 1975-1994. 2-12
Figure 2-14: Trend in annual mean NO2 concentrations, 1985-1994. 2-14
Figure 2-15: National total NOX emissions trend, 1985-1994. 2-14
Figure 2-16: NOX emissions by source category, 1994. 2-14
Figure 2-17: NO2 annual mean concentration trends by location, 1985-1994. 2-14
Figure 2-18: Highest NO2 annual mean concentration by county, 1994. 2-15
Figure 2-19: Trend in annual second daily maximum 1-hour O3 concentrations, 1985-1994. 2-17
Figure 2-20: O3 second daily maximum 1-hour concentration trends by location, 1985-1994. 2-17
Figure 2-21: Highest O3 second daily maximum 1-hour concentration by county, 1994. 2-18
Figure 2-22: Long-term ambient O, trend, 1975-1994. 2-18
Figure 2-23: National total VOC emissions trend, 1985-1994. 2-18
Figure 2-24: VOC emissions by source category, 1994. 2-19
Figure 2-25: Trend in annual mean PM-10 concentrations, 1985-1994. 2-21
Figure 2-26: National total PM-10 emissions trend, 1985-1994 (traditionally inventoried sources only). 2-21
Figure 2-27: PM-10 annual mean concentration trends by location, 1985-1994. 2-21
Figure 2-28: PM-10 emissions from traditionally inventoried source categories, 1994. 2-21
Figure 2-29: PM-10 total emissions by source category, 1994. 2-22
Figure 2-30: Highest second maximum 24-hour PM-10 concentration by county, 1994. 2-22
Figure 2-31: Highest second maximum 24-hour SO2 concentration by county, 1994. 2-24
Figure 2-32: Trend in annual mean SO2 concentrations, 1985-1994. 2-24
Figure 2-33: National total SO2 emissions trend, 1985-1994. 2-24
Figure 2-34: SO2 total emissions by source category, 1994. 2-25
Figure 2-35: SO, annual mean concentration trends by location, 1985-1994. 2-25
Figure 2-36: Long-term ambient S02 trend, 1985-1994. 2-25
Figure 2-37: Annual average light extinction. 2-26
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Figure 2-38: (a) Trend in 75th percentile light extinction, 1960. 2-27
Figure 2-38: (b) Trend in 75th percentile light extinction, 1970. 2-27
Figure 2-38: (c) Trend in 75th percentile light extinction, 1980. 2-27
Figure 2-38: (d) Trend in 75th percentile light extinction, 1990. 2-27
Figure 3-1: Photochemical Assessment Monitoring Stations (PAMS) Program 3-2
Figure 3-2: Predicted vs. observed ozone levels; Southeast site, 1993 data. (MET and VOC data) 3-5
Figure 3-3: Comparison of daily PM-10 and three o'clock p.m ozone concentrations on July 7, 1994. 3-6
Figure 3-4: Estimated urban B/T and X/T ratios from Atlanta source profiles (from Henry et al., 1994). 3-7
Figure 3-5: Measured urban B/T and X/T ratios from East Hartford, CT PAMS site during July 1994 episodes. 3-7
Figure 3-6: Predicted changes in B/T and X/T ratios at rural sites (resulting from airmass aging). 3-7
Figure 3-7: Measured rural B/T and X/T ratios from Stafford, CT PAMS sites during July 1994 episodes. 3-7
Figure 3-8: Maximum ozone concentrations and hour of occurrence on July 21, 1994. 3-8
Figure 3-9: 8-hour moving average ozone concentrations on July 21, 1994. 3-8
Figure 4-1: Trends in HAP Emissions (1989-1993). 4-1
Figure 4-2: Total HAPs emissions for 1993. 4-3
Figure 4-3: Changes in TRI estimates of HAP emissions by state, 1989-1993. 4-4
Figure 4-4: Changes in TRI estimates of HAP emissions by state, 1992-1993. 4-4
Figure 4-5: Comparison of annual TRI emission estimates for the top 10 HAPs from 1989-1993. 4-5
Figure 4-6: Comparison of annual HAP emissions for the top 10 industrial categories from 1989-1993. 4-5
Figure 4-7: Cumulative number of source categories with MACT standards promulgated (1990-1995). 4-9
Figure 4-8: Cumulative emission reductions from promulgated MACT standards (1990-1995). 4-9
Figure 4-9: Emission reductions (greater than 5000 tons/year) from promulgated MACT standards (1990-1995). 4-10
Figure 4-10: Emission reductions (less than 5000 tons/year) from promulgated MACT standards (1990-1995). 4-10
Figure 5-1: Location of nonattainment areas for criteria pollutants. 5-2
Figure 5-2: O3 nonattainment areas by degree of severity. 5-4
Figure 6-1: Pollutant Standards Index 6-3
Figure 6-2: Total number of PSI days greater than 100 in the 90 largest cities. 6-4
Figure 7-1: Emissions of sulfur dioxide from anthropogenic sources in selected countries, 1970 to 1990, 7-1
Figure 7-2: Paniculate matter emissions from anthropogenic sources in selected countries, 1970 to 1990, 7-2
Figure 7-3: Global anthropogenic emissions of greenhouse gases, 1990. 7-4
Figure 7-4: GEMS: 1990 sulfur dioxide and participate matter monitors location and sample data. 7-6
Figure 7-5: Maximum daily average ozone levels at selected world cities, 1991. 7-6
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994 vii
-------
Tables
Table 2-1: NAAQS in effect in 1994. 2-2
Table 3-1: PAMS target list of VOCs. 3-3
Table 3-2: Most abundant anthropogenic VOCs in selected measurement campaigns. 3-5
Table 4-1: Major pollutants controlled by standards promulgated (1900-1995). 4-7
Table 5-1: Nonattainment area counts for NAAQS pollutants. 5-1
Table 6-1: Pollutant Standards Index values with pollutant concentrations, health descriptors, and PSI colors. 6-2
Table 7-1: Emissions of nitrogen oxides from anthropogenic sources in selected countries, 1985 and 1990. 7-3
Table 7-2: WHO health guidelines. 7-4
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Chapter 1
Executive
Summary
The following is the 22nd annual report documenting air
pollution trends in the United States. This report
primarily focuses on, pollutants for which the United
States Environmental Protection Agency (EPA) has
established National Ambient Air Quality Standards
(NAAQS). The Clean Air Act (CAA) provides for two
types of standards. Primary standards set limits to
protect the public health, including sensitive
populations such as asthmatics, children and the
elderly. Secondary standards set limits to protect the
public welfare, including animals, crops, vegetation,
and buildings. There are six criteria pollutants with
primary standards: carbon monoxide (CO), lead (Pb),
nitrogen dioxide (NO2), ozone (O3), particulars matter
whose aerodynamic size is less than or equal to 10
microns (PM-10), and sulfur dioxide (SO2).
Each year, EPA analyzes air quality data for the
most recent 10-year period. Specific monitoring sites
are included in this trend analysis only if they have
complete data for a minimum of eight out of the 10
years. In 1987, the standard for Total Suspended
Particulates (TSP) was replaced with the PM-10
standard. Therefore, PM-10 trend analyses are based
on data collected at monitoring sites that have
complete data for six out of the seven years between
1988 and 1994. This report contains data accumulated
on criteria pollutants between 1985 and 1994 from
more than 4,000 monitoring stations around the
country.
It is important to note that discussions of ozone
refer to ground level, or tropospheric ozone, as
opposed to stratospheric ozone. In the stratosphere,
miles above the earth, ozone acts as a screen from the
sun's ultraviolet rays. Ozone at ground level (in the air
we breathe) is a health concern as well as an
environmental concern. It is the primary ingredient of
what is commonly known as smog. However, ozone is
not emitted directly into the air; rather it is created
when sunlight reacts with oxides of nitrogen and
volatile organic compounds (VOCs) in the ambient air.
EPA tracks ambient air quality trends for criteria
pollutants based on direct measurements of pollutant
concentrations in the air at selected sites throughout the
country. Additionally, EPA tracks air emission trends
based on estimates of total tonnage of criteria
pollutants released into the air annually. Emission
trends are estimated using the best available
engineering calculations. These calculations express
the level of industrial activity, changes in technology,
fuel consumption, VMT, and other air polluting
activities. Emission trends reflect emissions from
natural sources, changes in air pollution regulations,
and the installation of emission controls.
A 10-year period is convenient for considering
ambient pollution trends because of the changes that
occurred in monitoring networks during the early
1980s, as well as the changes that routinely occur in
the geographic distribution of monitors. Although it is
difficult to provide ambient trends going back more
than 10 years, it is important not to overlook some of
the earlier control efforts in the air pollution field.
While ambient monitoring trends and emission trends
can be viewed as independent assessments of the
underlying pollutant trends, emission estimates can
also be used to provide information on longer time
periods. Figure 1-1 provides a convenient summary of
emission changes for all six NAAQS pollutants
between 1970 and 1994. Emissions for all criteria
pollutants except nitrogen oxides decreased between
1970 and 1994, the greatest success story being a 98-
percent decrease in Pb emissions.
These reductions occurred during a period of
significant population and economic growth. Since
1970, total U.S. population increased 27 percent,
vehicle miies traveled (VMT) increased 111 percent,
and the gross domestic product increased 90 percent as
noted in Figures 1-2 through 1-4.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
1-1
-------
MILLION SHORT TONS/YEAR
160
140
120
100
80
60
40
20
0
CO
(-23%)
NOx
(+14%)
voc
(-24%)
PM10
(-78%)
SOx
(-32%)
1970
1994
THOUSAND
SHORT TONS/YEAR
250
200
LEAD
(-98%)
Figure 1-1; Summary of emissions changes for all sixNAAQS pollutants between 1970 and 1994.
27% increase, 1970 to 1994
MILLIONS OF PEOPLE
300
250
200
150
100
50
0
260
227
204
1970
Sources: U.S. Bureau of the Census
Figure 1-2: Total U.S. population, 1970-1994.
1980
1994
1-2
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Between 1985 and 1994, ambient air quality
measurements at selected monitoring sites revealed the
following data:
Carbon monoxide concentrations decreased
28 percent.
* Lead concentrations decreased 86 percent.
Nitrogen dioxide concentrations decreased
9 percent.
Ozone concentrations decreased 12 percent,
Particulatc matter concentrations decreased
20 percent (between 1988 and 1994).
* Sulfur dioxide concentrations decreased
25 percent.
These air quality improvements are a direct result of
effective implementation of clean air laws and reg-
ulations. Despite the increase in U.S. population, total
VMT, and gross domestic product since 1970, there is
strong evidence of a general trend of air quality im-
provement.
Between 1985 and 1994, emission estimates
revealed the following data:
« Carbon monoxide emissions decreased
15 percent.
Lead emissions decreased 75 percent.
Emissions of nitrogen oxides increased
3 percent.
Emissions of volatile organic compounds
(largely responsible for ozone formation)
decreased 10 percent.
Partieulate matter emissions (between
1988 and 1994) decreased 12 percent.
* Sulfur dioxide emissions decreased
9 percent.
Emissions are affected by the nation's economic
activity, meteorological conditions, and regulatory
controls. The slight increase observed in NOX
emissions is attributed to increased production and
processing by industry and greater fuel combustion by
electric utilities.
While progress has been made, it is important not
to lose sight of the magnitude of the air pollution
problem that still remains. Figure 1-5 summarizes the
number of people living in counties with air quality
levels above the NAAQS. About 62 million people in
the United States reside in counties that did not meet a
minimum of one air quality standard based on 1994
monitoring data. The ground level O3 standard is the
most commonly violated standard, based on both
population and number of areas not meeting standards.
In 1994, 50 million people lived in counties that
exceeded the O3 standard. However, 1994 is the third
consecutive year that every monitoring site in the
country met the NO, standard. With respect to SO2, it
is important to note that while most monitoring sites
are currently meeting ambient standards, SO, problems
in the United States are associated with point sources
and are typically identified by modeling rather than by
routine ambient monitoring. The population estimates
in Figure 1-5 are based only upon a single year of data,
1994, and only consider counties with monitoring data
for that pollutant. For example, the number of people
living in nonattainment areas as of September 1995
was approximately 134 million (based on the formal
designations of nonattainment areas) as opposed to 62
million (based on those counties with air quality data
that exceeded any NAAQS in 1994). There are two
reasons for this difference in population estimates.
First, formal designations generally encompass entire
metropolitan areas rather than just the county with the
monitor. Second, formal designations are based on
multiple years of data (rather than the most recent
calender year) to account for a broader range of
meteorological conditions.
Although this report emphasizes those six
pollutants for which NAAQS exist, there are other air
pollutants of concern. Air toxics are chemicals known
or suspected of causing cancer or other serious health
effects (e.g., reproductive effects). According to EPA's
Toxic Release Inventory (TRI), estimated emissions of
hazardous air pollutants (189 compounds identified for
regulatory attention by the CAAA) declined 33 percent
between 1989 and 1993, with an 8-percent decrease
reported between 1992 and 1993. Control programs
designed to address criteria pollutant reductions also
reduce air toxic releases to some degree (by reducing
emissions of particulates, VOCs, and NOJ. However,
Title III of the CAA (section 112 of the CAAA)
provides specific new tools to directly address releases
of hazardous air pollutants. EPA is also implementing
programs to reduce emissions of pollutants
contributing to O3 depletion in the stratosphere and
acidic deposition (i.e., acid rain).
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
1-3
-------
111 % increase, 1970 to 1994
BILLIONS OF MILES
3500
3000
1970 1980
Figure 1-3: Total U.S. vehicle miles traveled, 1970-1994.
1994
90% increase, 1970 to 1994
BILLIONS OF DOLLARS
,000
1970
1980 1994
Figure 1-4: Total U.S. Gross Domestic Product, 1970-1994.
1-4
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Any NAAQS
Figure 1-5: Number of people living in counties with air quality levels above the NAAQS in 1994.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
1-5
-------
Chapter 2
Air Quality
Trends
EPA has established National Ambient Air Quality
Standards (NAAQS) for six criteria pollutants to
protect public health and welfare. These six pollutants
are carbon monoxide (CO), lead (Pb), nitrogen
dioxide (NCy, ozone (Qj), particulate matter whose
aerodynamic size is less than or equal to 10 microns
(PM-10), and sulfur dioxide (SOj). Table 2-1 lists the
NAAQS for each pollutant in terms of the level of the
standard, the associated averaging time, and the form
of the statistic used to evaluate compliance. There are
primary standards for all of the criteria pollutants.
Some pollutants (PM-10 and SO2) have primary
standards for both long-term (annual average) and
short-term (24-hours or less) averaging times. Short-
term standards are established to protect the
population from any adverse health effects associated
with acute exposure to air pollution, while long-term
standards are established to protect the population
from any adverse health effects associated with
chronic exposure to air pollution. The secondary
standard for most pollutants is the same as the primary
standard, except for SO2
Most air quality trends information is based on
data from three related indicators:
« Measurements of pollutant concentrations in
the ambient air.
Estimates of total national pollutant emissions.
The number of times that air quality standards
are violated.
National trends in air quality are derived from
routine measurements recorded over time at
monitoring sites located primarily in urban and
suburban areas, and to a lesser extent in selected rural
areas. These monitoring stations are operated by
state, tribal, and local government agencies as well as
some federal agencies. The national air quality trends
calculated for this report were derived from the
composite average of direct measurements of air
concentrations obtained from monitoring sites (see
Table A-10 of Appendix A). The averaging times and
air quality statistics used in these trends calculations
relate directly to ambient air quality standards.
Another indicator of air quality trends is the
estimated total of nationwide emissions. This estimate
is based on engineering calculations of the amounts
and kinds of pollutants emitted by automobiles,
factories, and other sources over a given period.1
Although air pollutant concentrations can only be
reduced over time by decreasing or eliminating
pollutant emissions, changes in pollutant
concentrations do not always track changes in
pollutant emissions resulting from human activities.
There are four primary reasons for the differences
observed between trends in concentrations and trends
in emission estimates. First, because most monitors
are positioned in urban, population-oriented locales,
air quality trends are more likely to track changes in
urban emissions rather than changes in total national
emissions. Urban emissions are generally dominated
by mobile sources, while rural areas are more likely
to be dominated by large stationary sources such as
power plants and smelters. Second, emissions for
some pollutants are calculated or measured in a
different form man the primary air pollutant. For
example, concentrations of N02 are caused by
emissions of oxides of nitrogen which include nitric
oxide and NO2- Also, concentrations of O3 are caused
by emissions of volatile organic compounds (VOCs)
and oxides of nitrogen. Third, the amount of each
pollutant measured at monitoring locations depends on
what chemical reactions occur in the atmosphere
during the time it takes the pollutant to travel from its
source to the monitoring station. Fourth, meteor-
ological conditions can be conducive to the formation
and buildup of pollutants in the ambient air. For
example, peak O3 concentrations typically occur
during hot, dry, stagnant summertime conditions (i.e.,
high temperature and strong solar insolation). In
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
2-1
-------
contrast, CO is predominately a cold weather problem
with peak CO concentrations occurring during the
winter months. The temporal variation in paniculate
levels may also be attributed to fluctuations in
meteorological conditions, especially precipitation.
Rainfall has the effect of reducing re-entrainment of
particles and washing particles out of the air. Also,
drier conditions are associated with an increase in the
frequency of forest fires.
This chapter describes air quality and emissions
trends for each of the six criteria pollutants.
Interested readers will find a discussion of the trends
methodology in Appendk B, and an expanded section
containing data tables in Appendix A.
fable 2-1: NAAQS in effect in 1994.
Parenthetical value is an approximately equivalent concentration.
Not to be exceeded more than once per year.
The standard is attained when the expected number of days per calendar year with maximum hourly average concentrations
above 0.12 ppm is equal to or less than one, as determined according to Appendix H of the Ozone NAAQS.
Participate standards use PM-10 as the indicator pollutant. The annual standard is attained when the expected annual
arithmetic mean concentration is less than or equal to 50 fig/m3; the 24-hour standard is attained when the expected number of
days per calendar year above ISQ.^g/m1 is equal to or less than one, as determined according to Appendix K of the PM
NAAQS.
2-2
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Carbon Monoxide (CO)
Mature and Sources
CO is a colorless, odorless, poisonous gas formed
when carbon in fuels is not burned completely. It is
a by-product of motor vehicle exhaust, which
contributes more than three-fourths of all CO
emissions nationwide. In cities, automobile exhaust
can cause as much as 95 percent of all CO
emissions. These emissions can result in high con-
centrations of CO particularly in local areas with
heavy traffic congestion. Peak CO concentrations
typically occur during the colder months of the year
when CO automotive "cold start" emissions are
greater and nighttime inversion conditions are more
frequent. Other sources of CO emissions include
industrial processes, non-transportation fuel
combustion, and natural sources such as wildfires.
Despite an overall downward trend in
concentrations and emissions of CO, some
metropolitan areas still fail to meet the CO NAAQS.
Health Effects
CO enters the bloodstream and reduces oxygen
delivery to the body's organs and tissues. The
health threat from CO is most serious for those who
suffer from cardiovascular disease. At higher levels
of exposure, healthy individuals are also affected.
Exposure to elevated CO levels is associated with
visual impairment, reduced work capacity, reduced
manual dexterity, poor learning ability, and
difficulty in performing complex tasks. There are
two primary NAAQS for ambient CO, a 1-hour
average of 35 ppm and an 8-hour average of 9 ppm.
These standards cannot be exceeded more than once
per year.
Trends
Long-term improvements continued between 1985
and 1994. Figure 2-1 indicates that national average
CO levels decreased 28 percent during the past 10
years as measured by the composite average of the
annual second highest 8-hour concentration.
National total CO emissions decreased 15 percent
since 1985 as illustrated in Figure 2-2. The ambient
trends plotting points and emissions totals by source
category are listed in Tables A-l and A-2 of
Appendix A.
Because the urban CO monitoring network is
primarily mobile-source oriented, CO air quality im-
provements track the estimated 21 percent reduction
in highway vehicle emissions. This air quality im-
provement occurred across all monitoring environ-
ments (see Figure 2-3) despite a 32-percent increase
in miles traveled in the United States since 1985.
Between 1993 and 1994, national average CO
concentrations increased two percent, while total
CO emissions increased four percent. This one year
increase in the national average concentration has a
distinct regional component which is likely associ-
ated with the year to year differences in meteorologi-
cal conditions. Ambient concentrations increased in
the northeastern and north central regions of the
country coinciding the much colder than normal
winters in those regions. Except for southern Cali-
fornia, the remainder of the country continued the
downward trend in ambient CO levels. The map in
Figure 2-4 shows the variations in CO concentra-
tions across the country in 1994. The air quality
indicator is the highest annual second maximum 8-
hour concentration measured in each county. The
bar chart to the left of>the map displays the number
of people living in counties within each concentra-
tion range. The colors on the map and bar chart
correspond to the colors for the concentration
ranges displayed in the map legend. Ten counties
(with a total population of approximately 15 million)
had second maximum 8-hour concentrations greater
than 9 ppm in 1994.
The composite average of the estimated number
of exceedances of the CO NAAQS declined 92
percent between 1985 and 1994. The large differ-
ence between the rate of change in concentrations
and the percentage change in exceedances is due to
the nature of the exceedance statistic (which is
simply a count of a pass/fail indicator). As noted
above, the trend in the annual second maximum 8-
hour concentration tracks the trend in highway
vehicle emissions.
Figure 2-5 shows that transportation sources
now account for 78 percent of the nation's total CO
emissions. The observed increase in CO emissions
between 1993 and 1994 is attributed to two sources;
transportation emissions (up two percent) and
wildfire emissions (up 159 percent) exacerbated by
NATIONAL Aia QUALITY AND EMISSIONS TRENDS REPORT, 1994
2-3
-------
1985-94: 28% decrease
1993-94: 2% increase
CONCENTRATION, PPM
15 r- - -- -
328 SITES
t
190% of sites have lower
; 2nd max B-hr concentrations
I than this line
85 86 87 88
Figure 2-1: Trend in second maximum non-
overlapping 8-hour average CO concentrations,
1985-1994.
the dry conditions in the West and Northwest
regions.
Ten-year trends in ambient concentrations are
the focus of this report since changes over time in
monitoring methods and site locations limit the
number of sites having the continuous data record
needed for a long-term trends assessment. Although
it is difficult to provide a quantitative assessment,
qualitative long-term comparisons can be made.
Figure 2-6 illustrates the improvement in ambient
CO air quality during the past 20 years. The appar-
ent discontinuity between the endpoint of the
1975-1984 trend line and the first year of the
1985-1994 trend line results from differences in the
mix of trend sites for the two periods (141 vs. 328
sites). The plotting points for the 20-year trend
charts are listed in Table A-9 of Appendix A.
1985-94:15% decrease
1993-94: 4% incerase
THOUSAND SHORT TONS PER YEAR
140,000
120,000
100,000
80,000
!£fejw
r~| Fuel Comfcuslion 1
^ Transportation |
jA^
Endystria] Processing
| Miscellaneous
\ I I
figure 2-2: National total CO emissions trend,
1985-1994:
Concentration, ppm
urhan(183 sitesj
suburban{137 sites)
turat[6 sites)
85 86 87 88 89 90 91 92 93 94
Figure 2-3: CO second maximum 8-hour
concentration trends by location, 1985-1994.
2-4
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Carbon Monoxide Air Quality Concentrations, 1994
Hlglwtt Second Hue ft-Hour Anragt
Figure 2-4: Highest CO second maximum 8-hour concentration by county, 1994.
"^^^
78.3%
7.3%
5.0%
9.4%
| Fuel Combustion g| Industrial Processes
I Transportation [~j Miscellaneous
Figure 2-5: CO emissions by source category,
1994,
14
12
10
Concentration, ppm
1975-84 198S-94
(141 sites) (328 sites)
76 78 80 82 84 86 SB 90 92
(Composite Annual 2nd Max 8-hr Concentration)
Figure 2-6; Long-term ambient CO trend,
1975-1994.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
2-5
-------
Lead (Pb)
Nature and Sources
In the past, automotive sources were the major
contributor of Pb emissions to the atmosphere. As a
result of EPA's regulatory efforts to reduce the
content of Pb in gasoline, the contribution from the
transportation sector has declined. Today, smelters,
battery plants, followed by highway vehicles are the
major sources of Pb emissions to the atmosphere. The
highest concentrations of Pb are found in the vicinity
of nonferrous smelters and other stationary sources of
Pb emissions.
Health Effects
Exposure to Pb mainly occurs through the inhalation
of air and the ingestion of Pb in food, water, soil, or
dust. Pb accumulates in the body in blood, bone, and
soft tissue. Because it is not readily excreted, Pb can
also affect the kidneys, liver, nervous system, and
other organs. Excessive exposure to Pb may cause
neurological impairments such as seizures, mental
retardation,- and/or behavioral disorders. Even at low
doses, Pb exposure is associated with changes in
fundamental enzymatic, energy transfer, and homeo-
static mechanisms in the body. Fetuses and children
are especially susceptible to low doses of Pb, often
suffering central nervous system damage. Recent
studies show that Pb may be a factor in high blood
pressure and subsequent heart disease in middle-aged
white males. The primary NAAQS for Pb is a
quarterly average concentration not to exceed 1.5
jtg/m3.
Trends
Figure 2-7 indicates that between 1985 and 1994,
quarterly average Pb concentrations in urban areas
throughout the country decreased 86 percent, while
Figure 2-8 shows that total Pb emissions decreased 75
percent. These reductions are a direct result of the
use of unleaded gasoline in automobiles. During the
last 10 years, Pb emissions from highway vehicles
decreased 91 percent. Figure 2-9 reveals that the air
quality trends at urban and suburban locations are
similar, which is not surprising since highway vehicles
are the major emission source at these locations. The
large reduction in Pb emissions from transportation
sources has changed the nature of the ambient Pb
problem in the United States. The map in Figure 2-10
shows the 1994 peak quarterly concentrations
measured in the vicinity of major Pb sources. Despite
the reduction of lead from transportation sources,
there are still violations of the Pb standard around
some Pb point sources. The Pb monitoring strategy
now focuses on these point sources of Pb emissions.
For example, various enforcement and regulatory
actions are being actively pursued by EPA and the
States for those sources shown on the map recording
violations of the Pb NAAQS. The map in Figure 2-11
shows how the highest quarterly mean Pb
concentration varied by county in 1994. Ten
counties, with a total population of 4.4 million and
containing the point sources from Figure 2-10, did not
meet the Pb NAAQS in 1994.
Between 1993 and 1994, Pb emissions remained
unchanged, while national average Pb concentrations
(approaching the minimum detectable level) decreased
20 percent. Figure 2-12 shows that the two major
categories of Pb emissions are industrial processes
(58 percent) and emissions from transportation sources
(32 percent). A listing of Pb emissions by major
source category is provided in Table A-3 of Appendix
A. The long-term Pb success story is that ambient Pb
concentrations have been reduced by more than 97
percent since 1975, as illustrated in Figure 2-13.
2-6
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
1985-94: 86% decrease
1993-94:20% decrease
CONCENTRATION, UG/M
1.5
NAAQS
90% of sites have lower
Max Quarterly Means
0 5 -K than this line
197 SITES
8S 86 87 SB 89 90 91 92 93 94
Figure 2-7: Trend in maximum quarterly average
Pb concentrations, 1985-1994.
1985-94: 75% decrease
1993-94: no change
SHORT TONS PER YEAR
Fuel Combustion fj Industrial Processing
Transportation
25,000
20,000
15,000
10,000
5,000
85 86 87 88 89 90 91 92 93 94
Figure 2-8: National total Pb emissions trend,
1985-1994.
0,35
0,3
0.2S
0.2
0.15
0.1
O.OS
Concentration, ug/m3
urt>an(W sites)
85 86 87 88 89 90 91 92 93 94
Figure 2-9: Pb maximum quarterly mean concen-
tration trends by location, 1985-1994.
Figure 2-10; Maximum quarterly Pb concentrations
in the vicinity of Pb point sources.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
2-7
-------
Lead Air Quality Concentrations, 1994
Hlglttit QuBTttrty Av«r«9»
Figure 2-11: Highest Pb maximum quarterly mean concentration by county, 1994.
57.9%
9.9%
32.2%
Fuel Combustion iH Industrial Processes
Transportation
Figure 2-12; Pb emissions by source category.
Concentration, ug/m3
2
is
0.5 -
j 1975-84 1985-94
'(43 sites) (197 sites)
76 ?B BO- 82 94 86 88 9D 92 94
(Composite Annual Max Quarterly Mean Cone.)
Figure 2-13: Long-term ambient Pb trend,
1975-1994.
2-8
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Nitrogen Dioxide (NO2)
Nature and Sources
Nitrogen dioxide belongs to a family of poisonous,
highly reactive gases called oxides of nitrogen (NOJ.
These gases form when fuel is burned at high
temperatures, and come principally from motor
vehicle exhaust and stationary sources such as electric
utilities and industrial boilers. A suffocating,
brownish gas, nitrogen dioxide is a strong oxidizing
agent that reacts with water to form corrosive nitric
acid. It also plays a major role in the atmospheric
reactions that produce O3.
Health and Other Effects
Nitrogen dioxide can irritate the lungs and lower
resistance to respiratory infections such as influenza,
The effects of short-term exposure are still unclear,
but continued or frequent exposure to concentrations
higher than those normally found in the ambient air
may cause increased incidence of acute respiratory
disease in children. The ambient NO2 primary
NAAQS is an annual mean concentration not to
exceed 0.053 ppm. Oxides of nitrogen are an
important precursor to both O3 and acidic precipitation
(acid rain) and may affect both terrestrial and aquatic
ecosystems. The regional transport and deposition of
atmospheric NO,, is a potentially significant
contributor to such environmental effects as the
growth of algae and subsequent unhealthy or toxic
conditions for fish in the Chesapeake Bay and other
estuaries. In some parts of the western United States,
oxides of nitrogen have a significant impact on
paniculate matter concentrations.
Trends
Nationally, annual mean NO2 concentrations remained
relatively constant throughout the 1980s, followed by
decreasing concentrations in the 1990s. The 1994
composite average of the N02 annual mean con-
centrations is nine percent lower than the 1985 level,
but five percent higher than the 1993 level, as
illustrated in Figure 2-14.
The trend in national total emissions of NOX is
shown in Figure 2-15. Since 1985, national total NO,
emissions increased 3 percent, while highway vehicle
NOK emissions declined seven percent and fuel com-
bustion emissions increased 8 percent. The two
primary sources of the NOX emissions in 1994 were
fuel combustion (50 percent) and transportation (45
percent) as shown in Figure 2-16. Table A-4 in
Appendix A provides a listing of NO* emissions by
major source category. The increase in NOX emissions
between 1993 and 1994 is attributed to increased
emissions from off-highway vehicles and wildfires.
Although the highest ambient NO2 levels are
typically observed in urban areas, Figure 2-17 shows
that the ambient NO2 air quality trends are similar
across monitoring locations. Even with an increase in
annual mean NO2 concentrations, 1994 is the third
consecutive year that all monitoring locations across
the nation, including Los Angeles, met the federal
NO2 air quality standard (see Figure 2-18). Twenty-
year trends in ambient NO2 concentrations are not
shown because the sites meeting the 1975-1984
completeness criteria (a total of 40 sites) are not
representative of the mix of 205 sites in the current
trends data base. The lack of data resulted in a large
discontinuity between the levels of the two trend lines.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
2-9
-------
1985-94; 9% decrease
1993-94: 5% increase
1985-94: 3% increase
1993-94:1% increase
CONCENTRATION, PPM
0.06 _-- . - -
THOUSAND SHORT TONS PER YEAR
30,000
NAAQS
205 SITES
0.05 j
i 90% of sites hive tower
0.04 4 Arith Mean coneentratians
than this line
0.03
0,02
0.01
0.00 - ------
85 86 87 88 89 90 91 92 93 94
25,000
Fuel Combustion | Industrial Processing
Transportation B Miscellaneous
T~ i 1 i I i i
85 86 87 88 89 90 91 92 93 94
Figure 2-14: Trend in annual mean NO2
concentrations, 1985-1994.
Figure 2-15: National total NOX emissions trend,
1985-1994.
3.8%
49.7%
45.0%
1.6%
Fuel Combustion
Transportation
Industrial Processes
Miscellaneous
0.03
0.025
0.02
0.015
0.01
0.005
Concentration, ppm
utban(71 sites)
suburt»an(34 silesj
nirat(3 sites)
85 86 87 8B 89 90 91 92 93 94
Figure 2-16: NOX emissions by source category, Figure 2-17: NO2 annual mean concentration trends
1994. by location, 1985-1994.
2-10
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Nitrogen Dioxide Air Quality Concentrations, 1994
Figure 2-18: Highest NO2 annual mean concentration by county, 1994.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
2-11
-------
Ozone (O3)
Nature and Sources
Ground-level O3 is the most complex, difficult to
control, and pervasive of the six criteria pollutants.
Unlike, other pollutants, O3 is not emitted directly into
the air by specific sources. A poisonous form of pure
oxygen, it is created when sunlight reacts with oxides
of nitrogen and VOCs in the air. There are
thousands of sources of these gases. Some of the
more common sources are gasoline vapors, chemical
solvents, combustion products of various fuels, and
consumer products. These products can frequently be
found in large industrial facilities, gas stations, and
small businesses such as bakeries and dry cleaners.
Often these "precursor" gases are emitted in one area,
but the actual chemical reactions, stimulated by
sunlight and temperature, take place in another.
Combined emissions from motor vehicles and
stationary sources can be carried hundreds of miles
from their origins, forming high O3 concentrations
over very large regions. Approximately 50 million
people lived in counties with air quality levels above
the primary O3 NAAQS in 1994. The highest levels
of O3 were recorded in Los Angeles. High levels also
persist along the Texas Gulf Coast and much of the
Northeast.
Health and Other Effects
While O3 in the upper atmosphere is beneficial in that
it shields the earth from harmful ultraviolet rays,
ground-level O3 causes health problems because it
damages lung tissue, reduces lung function, and
sensitizes the lungs to other irritants. Scientific
evidence indicates that ambient levels of O3 not only
affect people with impaired respiratory systems (such
as asthmatics) but healthy adults and children as well.
Exposure to O3 for six to seven hours, even at
relatively low concentrations, has been found to
significantly reduce lung function and induce
respiratory inflammation in normal, healthy people
during periods of moderate exercise. This decrease in
lung function is often accompanied by such symptoms
as chest pain, coughing, nausea, and pulmonary
congestion. Recent studies provide evidence of an
association between elevated ambient O3 levels and
increases in hospital admissions for respiratory
problems in several U.S. cities. Though less well
established in humans, animal studies have
demonstrated that repeated exposure to O3 for months
to years can produce permanent structural damage in
the lungs and accelerate the rate of lung function
decline and the aging of the lungs. Ambient O3 also
is responsible for several billion dollars of agricultural
crop yield loss in the United States each year. It also
causes noticeable leaf damage in many crops and
species of trees. Forest and ecosystem studies indicate
that damage is resulting from current ambient O3
levels. The ambient standard for O3 is 0.12 ppm daily
maximum 1-hour concentration not to be exceeded
more than once per year averaged over three calendar
years.
Trends
Ground level O3 (the primary constituent of smog) has
been a pervasive pollution problem throughout the
United States. Ambient O3 trends are influenced by
year-to-year changes in meteorological conditions as
well as emission reductions from ongoing control
measures. Although meteorological conditions in
1994 were conducive to O3 formation, especially in
the Southeast, Figure 2-19 reveals that the 1994
composite national average daily maximum 1-hour O3
concentration is 12 percent lower than the 1985
composite mean level. The national 1994 composite
mean is the second lowest national average of this 10-
year trends period. The lowest level was recorded in
1992 and the highest in 1988. The composite mean of
the number of exceedances of the O3 NAAQS declined
56 percent since 1985. Figure 2-20 shows that the
trends in composite mean second daily maximum 1-
hour concentrations are similar across monitoring
environments, while the highest levels are typically
found at suburban sites. During the past 10 years,
urban sites recorded the largest air quality
improvement (a 14 percent decline in O3
concentrations), followed by suburban sites (-12
percent) then rural sites (-nine percent). The map in
Figure 2-21 presents the highest second daily
maximum 1-hour concentration by county in 1994.
The accompanying bar chart to the left of the map
reveals that in 1994 approximately 50 million people
lived in counties where the second daily maximum 1-
hour concentration was above the level of the O3
NAAQS.
2-12
NATIONAL Am QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
As noted in a study by the National Academy of
Science, and in previous Trends Reports, O3 trends
are affected by changing meteorological conditions
that are conducive to O3 formation.2-3 EPA has
developed a statistical model that factors out
meteorological effects and helps reduce the degree of
uncertainty in the resulting trend estimates.* Results
from application of the model in 44 major urban areas
indicate that meteorologically adjusted O3 trends are
improving at a median rate of 1.1 percent per year
since 1984. Quantitative long-term ambient Q3 trends
assessments are difficult due to historical changes in
network design, siting criteria, spatial coverage and
monitoring instrument calibration procedures. Figure
2-22 contrasts the 1975-1984 composite trend line
based on 149 sites with the current 1985-1994
composite trend line based on 549 sites. Although
the overall trend is downward, short-term upturns
corresponding to peak O3 conducive years are evident.
The shaded area in the late 1970s indicates the period
corresponding to the old calibration procedure where
concentration levels are less certain.
Recent control measures include regulations to
lower fuel volatility as well as NO* and VOC
emissions from tailpipes,5 Figure 2-23 shows that
emissions of VOCs (which contribute to O3 formation)
decreased 10 percent between 1985 and 1994.
Nationally, the two major sources of VOC emissions
are industrial processes (56 percent) and transportation
sources (37 percent) as shown in Figure 2-24 or in
Table A-5 of Appendix A. NOS emissions (the other
major precursor to O3 formation) increased three
percent between 1985 and 1994.
1985-94:12% decrease
1993-94:1% decrease
CONCENTRATION, PPM
549 SITES
90% of sites have lower
2nd max 1-hr concentrations
than this line
0,25
0.20
0.15
0.10
0.05 ,
0.00
85 86 87 88 89 90 91 92 93 94
Figure 2-19: Trend in annual second daily
maximum 1-hour O3 concentrations, 1985-1994.
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0,02
Concentration, ppm
suburban(SS9 sites)
urtan(117 sites)
iural(155 siles)
0 L
85 86 87 88 '89 90 91 92 93 94
Figure 2-20: O3 second daily maximum 1-hour
concentration trends by location, 1985-1994.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
2-13
-------
Ozone Air Quality Concentrations, 1994
Hlghwt Second Dally 1 -Hour Max
Figure 2-21: Highest O3 second daily maximum 1-hour concentration by county, 1994.
Concentration, ppm
0-16
1975-84 1985-94
(149 sites) (549 sites)
1985-94:10% decrease
1993-94: 3% increase
THOUSAND SHORT TONS PER YEAR
30,000
25,000
20,000
15,000
10,000
5,000
QFuel industrial H Transportation ^ Miscellaneous
Combustion Processing
76 78 80 82 84 86 88 90 92 94
85 86 87 .88 89 90 91 92 93 94
Figure 2-22: Long-term ambient 03 trend,
1975-1994.
Figure 2-23: National total VOC emissions trend,
1985-1994.
2-14
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
56.3%
36.9%
3.8%
3.0%
Fuel Combustion H Industrial Processes
Transportation Q Miscellaneous
Figure 2-24: VOC emissions by source category, 1994.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
2-15
-------
Participate Matter (PM-10)
Mature and Sources
Partieulate matter is the general term for solid or
liquid particles found in the atmosphere. Some
particles are large or dark enough to be seen as soot
or smoke. Others are so small they can only be
identified with an electron microscope. Because
particles originate from a variety of mobile and
stationary sources, their chemical and physical
compositions vary widely depending on location and
time of year. In 1987, EPA replaced the earlier
Total Suspended Particulate (TSP) standard with a
PM-10 standard.6 The new standard focuses on
smaller particles that are likely to be responsible for
adverse health effects because of their ability to reach
the lower regions of the respiratory tract, PM-10
includes only those particles that have a mass less than
or equal to a standard particle with a diameter of 10
micrometers (0.0004 inches).
Health and Other Effects
Based on studies of human populations exposed to
ambient particle pollution (sometimes in the presence
of SO2) and laboratory studies of both animals and
humans, areas of concern for human health have been
identified as: negative effects on breathing and
respiratory systems, aggravation of existing
respiratory and cardiovascular disease, alterations in
the body's defense systems against foreign materials,
damage to lung tissue, carcinogenesis, and premature
death. The elderly, children, and people with chronic
obstructive pulmonary or cardiovascular disease,
influenza, or asthma are especially sensitive to the
effects of PM-10. In addition, PM-10 serves as a
carrier for a variety of toxic metals and compounds,
and is a major cause of reduced visibility in many
parts of the United States.
There are both short-term and long-term PM-10
NAAQS. The long-term standard specifies an expect-
ed annual arithmetic mean not to exceed 50 /ig/m3,
while the short-term 24-hour standard of 150 ftg/m3,
is not to be exceeded more than once per year.
Trends
Ambient monitoring networks were revised in 1987 to
measure PM-10 (replacing the earlier TSP standard
instruments). Between 1988 and 1994, the national
composite average of annual mean PM-10 concen-
trations decreased 20 percent, while estimated PM-10
emissions from traditionally inventoried sources
decreased 12 percent as shown in Figure 2-25 and
Figure 2-26. Urban and suburban sites have similar
trends and comparable average concentration levels
(see Figure 2-27). The trends at rural sites are
consistent with these urban and suburban patterns, al-
though the composite mean level is significantly
lower. Between 1993 and 1994, mean PM-10 con-
centrations remained unchanged, while PM-10
emissions increased one percent.
PM-10 emissions from traditionally inventoried
sources decreased 17 percent since 1985. Figure 2-28
shows that the three major categories, fuel
combustion, industrial processes, and transportation
contribute almost equally to the total. Emissions from
residential wood combustion decreased 50 percent in
the past 10 years. Table A-6 of Appendix A lists PM-
10 emission estimates from these sources for
1985-1994. On a national basis, fugitive sources
(e.g., emissions from agricultural tilling, construction,
and unpaved roads) contribute about 85 percent to
total PM-10 emissions as compared to the 15-percent
contribution from sources historically included in
emission inventories (See Figure 2-29), Misc-
ellaneous and natural source PM-10 emissions
estimates are provided in Table A-7 of Appendix A.
Figure 2-30 displays the highest second maximum
24-hour PM-10 concentration by county in 1994,
Though not shown here, when both the annual and 24-
hour standards are considered, there were 13 million
people living in 19 counties with PM-10 con-
centrations above the PM-10 NAAQS in 1994.
2-16
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
CONCENTRATION, UG/M
70 - -
1988-94; 20% decrease
1993-94: no change
3
60
: NAAQS
50
748 SITES
90% of sites have lower
Artlh Mean corrontrahons
than this Hna
89
90
91
92
34
Figure 2-2S: Trend in annual mean PM-1Q concen-
trations, 1985-1994.
1988-94:12% decrease
1993-94:1% increase
THOUSAND SHORT TONS PER YEAR
4,000
3,000
2,000
1,000
Fuel Combustion | Industrial Processing
Transportation
88 89 90 91
(no miscellaneous emissions)
93
94
Figure 2-26: National total PM-10 emissions trend,
1985-1994 (traditionally inventoried sources only).
35
30
25 -
20
15
10
Concentration, ugftn3
mhan(3S2 sites)
88
89
90
91
92 93
94
Figure 2-27: PM-10 annual mean concentration
trends by location, 1985-1994.
38.4%
34.7%
26.9%
| Fuel Combustion ffH Industrial Processes
[] Transportation
Figure 2-28: PM-10 emissions from traditionally
inventoried source categories, 1994.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
2-17
-------
85.4%
Manmade [U Fugitive dust pji] Fires Q Natural Sources
Figure 2-29; PM-10 total emissions by source
category, 1994.
PM-10 Air Quality Concentrations, 1994
Hlglwal Second Max 24-Hour Avtrago
:
Figure 2-30: Highest second maximum 24-hour PM-10 concentration by county, 1994.
2-18
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Sulfur Dioxide (SO2)
Nature and Sources
Sulfur dioxide belongs to the family of sulfur oxide
gases (SOJ. These gases are formed when fuel
containing sulfur (mainly coal and oil) is burned, and
during metal smelting and other industrial processes.
Most sulfur dioxide monitoring stations are located in
urban areas. The highest monitored concentrations of
sulfur dioxide are recorded in the vicinity of large
industrial facilities.
Health and Other Effects
The major health concerns associated with exposure to
high concentrations of sulfur dioxide include effects
on breathing, respiratory illness, alterations in the
lungs' defenses, and aggravation of existing
cardiovascular disease. Major subgroups of the
population that are most sensitive to sulfur dioxide
include asthmatics and individuals with cardiovascular
disease or chronic lung disease (such as bronchitis or
emphysema) as well as children and the elderly.
There are two primary NAAQS for SO2 that address
these health concerns: an annual mean concentration
of 80 fig/m3 (0.03 ppm) not to be exceeded, and a 24-
hour daily concentration of 365 jig/m* (0.14 ppm) not
to be exceeded more than once per year,
SO2 also can produce damage to the foliage of
trees and agricultural crops. Together, sulfur dioxide
and oxides of nitrogen are the major precursors to
acidic deposition (acid rain), which is associated with
the acidification of lakes and streams, accelerated
corrosion of buildings and monuments, and reduced
visibility. The secondary SO2 NAAQS, which
protects against such damage, is a 3-hour average
concentration of 1300 /tg/m3 (0.50 ppm) not to be
exceeded more than once per year.
Trends
The map in Figure 2-31 displays the highest
second maximum 24-hour SO2 concentration by
county in 1994. Only one county, containing a major
SO2 point source, failed to meet the ambient2SO
NAAQS in 1994. The national composite average of
SO2 annual mean concentrations decreased 25 percent
between 1985 and 1994 (see Figure 2-32), while SO2
emissions decreased nine percent (see Figure 2-33).
Between 1993 and 1994, national SO2 mean
concentrations decreased four percent, and SO2
emissions decreased two percent. Table A-8 of
Appendix A lists national total SO2 emission estimates
by source category between 1985 and 1994.
The difference between concentrations and emis-
sions trends is mainly a result of the location of the
ambient monitoring network. Historically, networks
are positioned in population-oriented locales.
However, fuel combustion sources, which comprise
88 percent of total national SO2 emissions (Figure 2-
34), tend to be located in less populated areas. Figure
2-35 reveals mat composite annual mean
concentrations at sites in urban and suburban locations
decreased 28 percent, while ambient levels decreased
14 percent at rural sites. The progress in reducing
ambient SO2 concentrations during the past 20 years
is portrayed in Figure 2-36. This reduction can be
accomplished by installing flue-gas control equipment
at coal-fired generating plants, reducing emissions
from industrial processing facilities such as smelters
and sulfuric acid manufacturing plants, reducing the
average sulfur content of fuels burned, and using
cleaner fuels in residential and commercial burners.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
2-19
-------
Sulfur Dioxide Air Quality Concentrations, 1994
KlfltwM Second H«c 24-Hour Awrag*
I -
Figure 2-31: Highest second maximum 24-hour SO2 concentration by county, 1994.
1985-94:25% decrease
1993-94: 4% decrease
CONCENTRATION, PPM
0.035 ,
0.030
0.025
0.020
0.015
0.010
NAAQS
90% of silos have lower
Aritti Mean concentrations
than this line
475 srrcs
Figure 2-32: Trend in annual mean SO2
concentrations, 1985-1994.
1985-94:9% decrease
1993-94:2% decrease
THOUSAND SHORT TONS PER YEAR
30,000
25,000
20,000
jy) Fuel Combustion | Industrial Processing
| Transportation
! I I I I I I I I
85 86 87 88 89 90 91 92 93 94
Figure 2-33: National total SO2 emissions trend,
1985-1994.
2-20
NATIONAL Am QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
87.6%
Fuel Combustion Industrial Processes PJ] Transportation
Figure 2-34: SO2 total emissions by source
category, 1994.
0,011
0.01
0.009
0.008
0.007
0.006
Concentration, ppm
ytban(146 sites)
nral[127ste»!
85 86 87 88 89 90 91 02 93 94
Figure 2-35: SO2 annual mean concentration trends
by location, 1985-1994.
OwcentmUon, ppm
0.018
0.012
0008
1975-84 198S-94
(149 sites)
76 78 80 62
Figure 2-36: Long-term ambient SO2 trend, 1985-1994.
88 90 92 S4
NATIONAL AIR QUALITY AMD EMISSIONS TRENDS REPORT, 1994
2-21
-------
Visibility
Nature and Sources of the Problem
Visibility impairment, which is most simply described
as the haze which obscures the clarity, color, texture,
and form of what we see, is actually a complex
problem that relates to several of the pollutants
discussed in this chapter. Visibility impairment is a
result of aerosols or gas mixtures and suspended
particles in the atmosphere. These gases and particles
cause light to be scattered or absorbed, thereby
reducing visibility.
Sulfates are the largest single contributor to light
extinction, or visibility reduction, in many parts of the
United States as shown in Figure 2-37. The pie charts
are scaled to indicate the relative difference in the
amount of light extinction by region. In the Appal-
achian Mountains, sulfates account for 68 percent of
visibility reduction. Organic carbon, the next largest
contributor, causes 16 percent of visibility reduction.
In most areas of the West and Alaska, sulfates and
organics contribute equally to light extinction. In
southern California, nitrate is the greatest contributor
to light extinction. Light absorbing carbon is
generally the smallest contributor to visibility
reduction at all monitoring sites.
Monitoring Technologies
In 1980, the National Park Service in cooperation with
EPA, established the Interagency Monitoring of
Protected Visual Environments (IMPROVE) network,
a long-term visibility monitoring program, at remote
locations throughout the United States.7 Since then,
several other Federal and regional organizations have
joined the effort. The IMPROVE network is devoted
to fully characterizing visibility.
Visibility impairment can also be studied by
analyzing the data collected since 1960 at 280 mon-
itoring stations located at airports across the country.
At these stations, measurements of visual range (the
maximum distance at which an observer can discern
the outline of an object) were recorded. Long-term
records of visual range help reveal trends in visibility.
There are two large contiguous haze regions in the
United States, one over the eastern states and another
over the Rocky Mountains and the Sierra-Cascade
ranges. Figure 2-38 reveals that this general pattern
has been preserved over the 30-year period beginning
in 1960, with intermittent changes in regional trends.
In the 1980s, haze reduction north of the Ohio River
and east of the Mississippi River continued, while
haze regions over the southeastern United States and
the Pacific states remained virtually unchanged.8
NORTHEAST
FLORIDA
SULFATE
ORGANICS
SOIL
LAC
NITRATE
S^^^sww^MS^^J^^J^^SJ^^^^SS^
Figure 2-37: Annual average light extinction.
2-22
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Programs to Improve Visibility
In April of 1994, EPA announced that it would begin
work on a Regional Haze Program to address
visibility impairment in Class I areas (national parks
and wilderness areas). This program will introduce
technical approaches to monitoring and modeling reg-
ional haze as well as define the policy for achieving
"reasonable progress" toward the national goal of
eliminating visibility impairment in these areas. The
program will be developed in coordination with
efforts of the Grand Canyon Visibility Transport
Commission. This commission is in the process of
developing recommendations for EPA regarding
protection of the Class I areas on the Colorado Plateau
in the southwestern United States. In addition to the
Regional Haze Program, better controls for sources of
criteria pollutants such as NO, could also lead to
improvements in visibility.
1960 Quarter 3
1570 Quarter 3
Figure 2-41: (a) Trend in 75th percentile light
extinction, 1960.
Figure 2-37: (b) Trend in 75th percentile light
extinction, 1970.
1990 Quarter 3
Figure 2-37: (c) Trend in 75th percentile light
extinction, 1980.
Figure 2-37: (d) Trend in 75th percentile light
extinction, 1990.
NATIONAL Am QUALITY AND EMISSIONS TRENDS REPORT, 1994
2-23
-------
References
. National Air Pollutant Emission Trends, 1900-1994, EPA-454/R-95-011, Environmental Protection Agency,
Office of Air Quality Planning and Standards, Research Triangle Park, NC, October 1995.
. Rethinking the Ozone Problem in Urban and Regional Air Pollution, National Research Council, National
Academy Press, Washington, DC, December 1991.
. National Air Quality and Emissions Trends Report, 1993, EPA-454/R-94-026, U.S. Environmental
Protection Agency, Office of Air Quality Planning and Standards, Research Triangle Park, NC, October
1994.
. W.M. Cox and S.H. Chu, "Meteorologically Adjusted Ozone Trends in Urban Areas; A Probabilistic
Approach", Atmospheric Environment, Vol. 27B, No. 4, Pergamon Press, Great Britain, 1993.
. Volatility Regulations for Gasoline and Alcohol Blends Sold in Calendar Years 1989 and Beyond, 54 PR
11868, March 22, 1989.
. National primary and secondary standards for particulate matter, 52 PR 24663, July 1, 1987.
. IMPROVE, Spatial and Temporal Patterns and the Chemical Composition of the Haze in the United States;
An Analysis of Data from the IMPROVE Network, 1988-1991, CIRA Cooperative Institute for Research
in the Atmosphere, Colorado State University, CO, February 1993.
,. R.B. Husar, J.B. Elkins, and W.E. Wilson, "U.S. Visibility Trends, 1960-1992," Air and Waste
Management Association 87th Annual Meeting and Exhibition, Cincinnati, OH, 1994.
-24
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Chapter 3
PAMS: Enhanced Ozone and Precursor
Monitoring
Of the six criteria pollutants, ozone (O3) is the most
pervasive. The most prevalent photochemical oxidant
and an important contributor to "smog", Os is unique
among the NAAQS pollutants in that it is not emitted
directly into the air, but instead results from complex
chemical reactions in the atmosphere between volatile
organic compounds (VOCs) and nitrogen oxides (NOx)
in the presence of sunlight. Further, there are thousands
of sources of VOCs and NOX located across the country.
To track and control O3 EPA must develop an
understanding of not only the pollutant, but the
chemicals, reactions, and conditions that contribute to its
formation as well.
Section 182(c)(l) of the 1990 Clean Air Act
Amendments (CAAA) called for improved monitoring of
O3 and its precursors, VOC and NO*, in order to obtain
more comprehensive and representative data on O3.
Responding to this requirement, EPA promulgated
regulations to initiate the PAMS (Photochemical
Assessment Monitoring Stations) program in February
1993. The PAMS program requires the establishment of
an enhanced monitoring network in all O3 nonattainment
areas classified as serious, severe or extreme. The 22
affected O3 areas, shown in Figure 3-1, cover 113
thousand square miles and have a total population of 79
million people.
Each PAMS network will consist of as many as five
monitoring stations, depending on the area's population.
PHOTOCHEMICAL ASSESSMENT MONITORING STATIONS
(PAMS)
PROGRAM
ARBAS SUBJECT TO
ENHANCED OZONE
MONITORING
f~0\ NUMBEROFAFFECTEOAREAS
lOr' TOTAL = 22
Figure 3-1: Photochemical Assessment Monitoring Stations (PAMS) Program
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
3-1
-------
These stations will be carefully located based on
meteorology and other conditions at the site. Generally,
each PAMS network will consist of four different
monitoring sites (Types 1,1,3, and 4) designed to fulfill
unique data collection objectives. The Type I site is
located upwind of the metropolitan area to measure O3
and precursors being transported into the area. The Type
2 site is referred to as the maximum precursor emissions
impact site1. As the name implies, it is designed to
collect data on the type and magnitude of O3 precursor
emissions emanating from the metropolitan area. The
Type 2 site are typically located downwind of the central
business district, and operate according to a more
intensive monitoring schedule than other PAMS stations.
The Type 2 sites are capable of measuring a greater array
of precursors and are also suited for the evaluation of
urban air toxics. The Type 3 stations are intended to
measure maximum O3 concentrations and are sited
downwind of the urban area and the Type 2 sites. The
Type 4 PAMS site is located downwind of the
nonattainment area to assess O3 and precursor O j levels
exiting the area and potentially contributing to the O3
problem in other areas.
Over its initial three years, the PAMS program has
exhibited steady and successful growth. Currently, there
are 57 PAMS surface air quality and meteorology
monitoring stations established and operating across the
nation. This represents at least one monitoring station in
each of the 20 areas involved in the PAMS program2.
Despite the ambitious schedule and "cutting edge" nature
of the monitoring technologies employed, data from
nearly all sites operating in 1993 and half those running
in 1994 have been reported to the Aerometric
Information Retrieval System (AIRS). AIRS is EPA's
national repository for air pollution data.
The data collected at the PAMS sites include
measurements of O3, NO x, a target list of VOCs
including several carbonyls (see Table 3-1) as well as
surface and upper air meteorology. Most PAMS sites
measure 56 target hydrocarbons on an hourly basis
during the O3 season. Included in the monitored VOC
species are nine compounds classified as hazardous air
pollutants (HAPs). The Type 2 sites also collect data on
carbonyl compounds (aldehydes and ketones) every three
hours during the O3 monitoring period. All stations
measure O3, NOX, and surface meteorological parameters
on an hourly basis.
The PAMS networks produce a wealth of
information invaluable to the development and
evaluation of O3 control strategies and programs. In
addition to providing a long term perspective on changes
in atmospheric concentrations of O3 and its precursors,
the PAMS program will help to improve emission
inventories, serve as input to photochemical grid models,
provide information to evaluate population exposure, and
provide routine measurements of selected HAPs. Most
importantly, PAMS will deliver a more complete
understanding of the complex problem of O3 so that we
may move toward the best solution to reduce O3
concentrations.
Currently, comprehensive analyses of the current
PAMS data are underway and an interpretation of the
results of such assessments is beyond the scope of this
report. However, significant attention and effort has
been recently directed to the analysis and interpretation
of the PAMS data. For example, preliminary
assessments of data from a Type 2 site in the Southeast
and one in the Mid Atlantic area yielded interesting
insights (albeit extremely exploratory) into relationships
between selected VOC species and O3 levels. Statistical
models of hydrocarbon concentrations and surface
meteorological conditions explained a significant portion
of the variability in downwind O3 (see Figure 3.2).
Surprisingly, the hydrocarbons (although selected based
on their correlation with the O3 values unique to the
individual PAMS areas) were similar despite the
expected differences in the VOC sources in the two
locations. While there is considerable additional work to
be performed to reproduce, strengthen and verify this
approach, the analyses are exciting, as they are a glimpse
into the potential advances that innovative PAMS data
analysis may offer. In addition, the Ambient Monitoring
and Assessment Committee of the Northeast states for
Coordinated Air Use Management (NESCAUM) and the
Lake Michigan Air Directors Consortium (LADCO)
recently released draft reports of their preliminary
examination of the PAMS data in their geographic areas.
Although exploratory in nature and based on a
limited sample of PAMS data (focuses on data collected
at six northeastern sites during two three-day episodes in
July, 1994), the NESCAUM report demonstrates the
variety of applications of PAMS data analysis and
reflects the value of the program to Federal arid State
ozone control efforts3. Selected analytic results and
interpretations from this report are summarized below.
Note that all results and interpretations are based on
analysis of data for the ozone episodes occurring on July
6-8,1994 and July 20-22, 1994.
3-2
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
The most active ozone-forming VOCs in the
NESCAUM region were formaldehyde, isoprene,
acetaldehyde, m/p-xylene and toluene. Together, these
5 compounds accounted for more than 75% of the
ozone formation potential during the studied episodes.
Table 3-2 contrasts these results for the most active
ozone-forming VOCs with those of a previous study in
the Northeast and an evaluation in California. An
earlier study, limited to the six a.m. to nine a.m. time
period in five Northeastern cities4, found six of the same
seven compounds leading the VOC abundance list.
Another, more extensive study of speciated VOCs5 in
the Los Angeles area, found the same seven
anthropogenic compounds to be most abundant and,
with the exception of propane, in virtually the same rank
of occurrence.
Of the targeted biogenic VOC compounds, only
isoprene (emitted predominantly by deciduous
vegetation) is currently quantifiable by most PAMS
sites in the Northeast. Isoprene levels during the 2
episodes examined here were higher than anticipated
(up to 25 - 35 ppbc) at several Northeastern sites.
These levels are similar to concentrations reported
during similar high temperature periods in the
Southeast, and are considerably higher than current
model estimates.
Short term exposures to high levels of ozone are
frequently characterized by relatively low levels of
benzene, relatively high levels of formaldehyde and
particulate matter.
As shown in Figure 3-3, the only day that PM-10
sampling was performed during the studied episode
periods (i.e., July 7, 1994) was characterized by high
regional PM-10 concentrations, exhibiting a similar
spatial pattern to the high, afternoon ozone values on that
day (note; PM-10 data from PA and more southerly
states were not available at time of extraction).
PAMS data have sufficient detail to quantify
effects of airmass aging, as more reactive VOC species
are photochemically destroyed during daytime
transport from urban centers to downwind sites,
Figure 3-4 displays the estimated benzene-to-toluene
(B/T) and xylene-to-toluene (X/T) ratios for urban areas
based on 1990 Atlanta source profiles and source mix.
Figure 3-5 shows the measured hourly B/T and X/T
ratios from the urban (type 2) PAMS site in East
Hartford, CT during the July, 1994 episode periods. The
scatter plot in Figure 3.5 reveals that toluene levels at the
East Hartford site were highly correlated with both
benzene and xylene - in a manner consistent with a
"common source" (i.e., fresh motor vehicle-related
emissions) and as expected for an urban area.
Figure 3-6 shows the hypothetical effect of aging on
Atlanta B/T and X/T ratios - benzene, toluene and m/p-
xylene will be less well correlated than in urban centers.
Figure 3-7 shows the measured B/T and X/T ratios for
the rural type 3 PAMS site in Stafford, CT (about 20
miles downwind of East Hartford) during the July 1994
episodes. The scatter plot in Figure 3-7 shows that the
B/T ratio at the downwind, rural Stafford site has
increased and the X/T ratio has decreased in comparison
to the urban East Hartford site. This is consistent with
the predicted effect of airmass aging, as the more
reactive species are differentially removed during
transport. The points plotted in Figure 3-7 also exhibit
greater scatter (B/T and X/T correlations are poorer) than
Figure 3-5. While common (motor vehicle-related)
sources are still anticipated to be a predominant cause of
benzene, toluene, and xylene at the Stafford site, the
species inter-correlations are diminished during
transport, as the degree of aging depends on variable
factors such as wind speed direction, solar radiation, OH,
NOX, etc.
The July 20-22/94 episode provides clear evidence
of the transport of both ozone and ozone precursors
(reactive VOCs and NO^) along the c«ast of Maine
from sources to the Southwest. In this case, the
transport of ozone itself appears to be more
important than the transport of precursors.
Routine ozone measurements alone can often provide
strong empirical evidence of transport. For example,
Figure 3-8 displays peak hourly concentrations and hour
of occurrence at sites along the north Atlantic coast on
7/21/94. Concentrations in excess of the 80 ppb Maine
State Standard were recorded at all of these coastal sites,
four of which also recorded exceedances of the federal
standard. With persistent southwesterly winds, the hour
of maximum concentration occurs progressively later in
the day as one moves to the northeast, ranging from 12
noon at Lynn, MA to as late as nine p.m. at Jonesport,
ME. The ozone levels from these North Atlantic Coastal
sites are also displayed as 8-hour running averages in
Figure 3-9, and provide a clear impression of ozone
transport along the coast.
More detailed, independent reports on the results and
interpretation of the analysis of PAMS data and
compilations of summary statistics for the previous
year's data are planned for future publication and annual
updates.
NATIONAL Am QUALITY AND EMISSIONS TRENDS REPORT, 1994
3-3
-------
Table 3-1: PAMS target list of VOCs.
Bm*^^
Acetylene
Eihylene
Ethane
Propylene
Propane
Isobulane
1-Butene
n-Bulane
trans-2-Buiene
cis-2-Butene
3-MethyI-l-Buiene
tsopentane
1-Pentene
Isoprene
Crans-2-Pentene
cis-2-Pentene
2-Meihyl-2-Butene
2,2-DimelhyIbutane
Aceialdehyde
Cyclopenlene
4-Melhyl-l-Pentene
Cyclopentane
2,3-Dimethylbutane
2-Methylpentane
3-MelhyIpentane
2-Methyl-l-Pentene
n-Hexane
(rans-2-Hexene
cis-2-Hexene
Methylcyclopentane
2,4-Dimethylpentane
Benzene
Cyclohexane
2-Melhylhexane
2,3-Dimeihylpenlane
3-Methylhexene
2,2,4-Trimethylpentane
Total NMOC
Acetone
n-Heptane
Methyl cyclohexane
2,3,4-Trimelhylpentane
Toluene
2-MelhyUieplane
3-Meihylheptane
n-Octane
Ethylbenzene
p-Xylene
Styrene
o-Xylene
n-Nonane
Isopropylbenzene
n-Propylbenzene
b-Pinene
1,3»S-Trimethylbenzcne
1,2,4-Trimelhylbenzene
B-Pinene
Formaldehyde
PREDICTED OZONE LEVELS VERSUS OBSERVED OZONE LEVELS
Southeast Site, 1993 Data
(MET and VOC data)
so.
40.
0 20 49 BO 80 103 120 140 ICO
PREDICTED OZONE LEVELS
WSSSSSSKSSffigs^
Figure 3-2: Predicted vs. observed ozone levels; Southeast site, 1993 data. (MET and VOC data)
3-4
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Table 3-2: Most abundant anthropogenic VOCs in selected measurement campaigns.
1.
2.
3.
4,
5.
6.
7.
Northeast '94
Isopentane
Toluene
Propane
Ethane
n-Butane
m/p-Xylene
n-Pentane
5 City '84
Isopentane
n-Butane
Toluene
n-Pentane
m/p-Xylene
Propane
Isobutane
Los Angeles '87
Propane
Isopentane
Toluene
n-Butane
Ethane
m/p-Xylene
n-Pentane
PM10D7-JIII-1994
03 07-JuH 99< 15:00
Figure 3-3: Comparison of daily PM-10 and three o'clock p.m ozone concentrations on July 7, 1994.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
3-5
-------
11
5.
X
f>
N *
i 3
GO
e 12
Toluene
16
20
u
a
a.
a
*
X
*
E
t>
N
4 8 12 16 20
Toluene (ppbc)
0 Xylerw itnztne
Figure 3-4: Estimated urban B/T and X/T ratios from
Atlanta source profiles (from Henry et al., 1994).
Figure 3-5: Measured urban B/T and X/T ratios from
East Hartford, CT PAMS site during July 1994
episodes.
*
c
o
O
>
N
C
m
8 12
Toluene
16
20
O.
a
t>
t
»
m
246
Toluene (ppbc)
0 Xylene
Benzene \
Figure 3-6: Predicted changes in B/T and X/T ratios at Figure 3-7: Measured rural B/T and X/T ratios from
rural sites (resulting from airmass aging). Stafford, CT PAMS sites during July 1994 episodes.
3-6
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
onesport (86 ppb at 21:00)
arbor, ME (102 ppb at 19:001
le Au Hunt, ME (116 ppb at 17:00)
Clyde, ME (124 ppb at 17:00)
ppsburg, ME (148 ppb at 15:00)
Cape Elizabeth, ME (148 ppb at 15:00)
Kennebunkport, ME (141 ppb at 14:00)
Rye, NH (135 ppb at 13:00}
Lynn, MA (105 ppb at 12:00)
Figure 3-8: Maximum ozone concentrations and hour of occurrence on July 21, 1994.
S
"" OB Q
Mi
luTTnT!.
itiilil! HniTl
Jmmtie
BvHMT.kC
MA1HU.ME
MQpfcME
nhpplOiim, ME
Qv»BiatBKll£
Kn«u*inltE
FVftW
« 5
Figure 3-9: 8-hour moving average ozone concentrations on July 21,1994.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
3-7
-------
Endnotes
1, A second Type 2 site may be required in some PAMS areas and would be positioned to capture the
precursor emissions in the second-most predominant morning wind direction. This additional Type 2
site constitutes the fifth PAMS site in the network,
2. Although there are 20 areas classified as serious, severe, or extreme for ozone, the flexibility of the
PAMS program allowed areas (in close proximity to one another) in two regions to consolidate their
monitoring operations. Therefore, only 20 PAMS networks exist.
3. The Ambient Monitoring and Assessment Committee, NESCAUM (Northeast States for Coordinated
Air Use Management). 1995. Preview of 1994 Ozone Precursor Concentrations in the Northeastern
United States, R, Poirot, ed. Boston, MA. The complete report is available from the NESCAUM office
(617-367-8540) or via the Internet from the CAPITA anonymous FTP server (capita.wustl.edu).
4. Wixtrom, R.N. and S.L. Brown. 1992. In: J. Exposure Analysis and Environmental Epidemiology*
Edo Pellizzari, ed. 2: 51 (averages recalculated here for 5 NE cities only.)
5. Lurmann, F.W. and H.H. Main. 1992. Analysis of Ambient VOC Data Collected in the Southern
California Air Quality Study. Report to California Air Resources Board. Sonoma Technologies, Inc.
Santa Rosa, CA.
3-8 NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Chapter 4
Air Toxics
Emission Trends
Extent of the Problem
In 1993, emissions of hazardous air pollutants (HAPs)
nationally totaled 1.2 billion pounds, as reported in
EPA's Toxic Release Inventory (TRI). This total
represents a decrease of approximately 600 million
pounds (or 33 percent) from 1989 levels, and of 110
million pounds (or eight percent) from 1992 levels as
illustrated in Figure 4-1. In comparison, between 1989
and 1993, total TRI air releases and total TRI releases
(to all media) declined 35 percent. Between 1992 and
1993, total TRI air releases decreased nine percent and
total TRI releases (to all media) decreased six percent.1A3
Figure 4-2 utilizes a grid map to present total HAP
emissions for 1993 by geographic area. In 1993, seven
states reported total HAP emissions of less than one
million pounds (Idaho joined the six states; New Mexico,
North Dakota, Wyoming, Hawaii, Nevada, and Vermont
SS8J8BSSSB
from 1992). In 1993, four states reported HAP releases
greater than 65 million pounds down from five states in
1992 and 11 in 1989.
Changes in the TRI estimates of HAP emissions by
state from 1989 to 1993 and 1992 to 1993 are depicted in
Figures 4-3 and 4-4. The total HAP emissions of 37
states have declined more than 25 percent from 1989
levels. While only one state reported net increases in
HAP emissions for the five-year period, seven states
estimate one-year increases in HAP releases since 1992,
Figure 4-5 compares annual TRI emission estimates
from 1989 to 1993 for the top 10 HAPs (based on 1989
levels). These estimates show a downward trend in
emissions for all 10 pollutants since 1989. However,
emissions of five of the 10 HAPs increased since 1992
[i.e.5 xylene (mixed isomers), chlorine, carbon disulfide,
hydrochloric acid, and trichloroethylene]. Similarly,
Figure 4-6 presents yearly HAP emissions for the top 10
industrial categories based on 1989 releases. All
industrial categories show decreased emissions since
1989-93: 33% decrease
1992-93: 8% decrease
Billion Pounds
Releases to all other roedk
Olhet Releases to «ir
Hazardous Air Pollulante
1989
1990
1991
1992
1993
Figure 4-1: Trends in HAP Emissions (1989-1993).
Source: Toxic Release Inventory
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
4-1
-------
Total Air Releases of Hazardous Air Pollutants for 1993
! iffiftfEyi to IHUQQJXX)
uum K» uotum
I loam ID mum
I IJJDDto HUH)
[ ik> isco
Figure 4-2; Total HAPs emissions for 1993.
1989 except for the paper products classification.
Between 1992 and 1993, emissions from the
transportation equipment, and furniture and fixture
industries increased, while the other eight categories
decreased. The chemical products industry has
consistently reported greater aggregate HAP emissions to
the TRI than any other source category.
Background and Further Details
Problem Definition
Hazardous air pollutants, also commonly referred to as
"air toxics," are pollutants that cause, or might cause,
severe health effects or ecosystem damage. Examples of
air toxics include dioxin, benzene, arsenic, beryllium,
mercury, and vinyl chloride. The Clean Air Act
Amendments (CAAA) list 189 pollutants as hazardous
air pollutants (HAPs) and specifically targets them for
regulation in Title III, section 112 (b)(l).* Air toxics are
emitted from all types of sources including stationary
sources, area sources, and mobile sources. Control of air
toxic pollutants differs in focus from controlling the six
principle National Ambient Air Quality Standards
(NAAQS) pollutants. For the six NAAQS pollutants,
control strategies are used in geographic areas where the
national air quality standards have been violated. In
contrast, EPA has focused on identifying all air toxics
emission sources and developing nationwide technology-
based performance standards for these sources. The
objective is to ensure that sources of air toxic pollution
are as well controlled as technology will allow,
regardless of geographic location.
The air toxics and the NAAQS programs
complement each other. Many air toxics are emitted in
the form of particulates or as organic compounds.
Control efforts to meet the NAAQS for ozone (O3) and
PM-10 will also reduce air toxic emissions. Further, as
air pollution control strategies for automobiles become
more stringent, air toxic emissions that can result from
vehicles are also reduced. Emission requirements under
the air toxics program can also significantly reduce
emissions of the six NAAQS pollutants. For example,
EPA's final air toxics rule for organic chemical
manufacturing is expected to reduce emissions of
Volatile Organic Compounds (VOCs), which form O3 or
ground-level smog, by nearly 1 million tons annually.
Many of these emission reductions are expected to
benefit geographic areas in meeting the national air
quality standards for ozone.
4-2
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Percent Change in Hazardous Air Pollutant (HAP) Air Releases
from 1989 to 1993
Figure 4-3; Changes in TRI estimates of HAP emissions by state, 1989-1993.
Percent Change In Hazardous Air Pollutant (HAP) Air Releases
from 1992 to 1993
19 Up to 29K Decrease (37)
O Sraater iha> SKt DBCTO«I» (6)
Figure 4-4: Changes in TRI estimates of HAP emissions by state, 1992-1993.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
4-3
-------
Top 10 Hazardous Air Pollutants
(1989 Base Year)
300
TOLUENE 1.1,1-mCMbOtOETHWE MBK- DICHLOROME1WNE KYOROCM£»IC*CID
MRHANOL XVieNI (HIKED EOMERS) CHLOfllNE CARBON QtSULHDE TBIOMLOROETOYLENE
M*r,1 Elh-,1 Krteoo
Figure 4-5: Comparison of annual TRI emission estimates for the top 10 HAPs from 1989-1993.
Top 10 Industrial Categories
(1889 Base Year)
pounds
500,000,000
400,000,000
300,000,000
200,000,000
100,000,000
0
1989 m 1990 n 1991 1992 ^ 1993
Figure 4-6: Comparison of annual HAP emissions for the top 10 industrial categories from 1989-1993.
4-4
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
The air toxics program is especially important in
reducing air emissions at or near isolated industrial
locations, and in controlling pollutants that are toxic even
when emitted in small amounts. Additionally, EPA has
developed mechanisms to prevent sudden, catastrophic
releases like the Bhopal, India chemical plant explosion
in 1985. Companies handling or using toxic chemicals
are required by EPA to develop programs to prevent
accidental releases, and to contain any releases in the
event an accident should occur.
Health and Other Effects
At sufficient concentrations and exposure durations,
human health effects from air toxics can include cancer,
poisoning, and immediate illness. Other less measurable
effects include immunological, neurological,
reproductive, developmental, and respiratory effects.
Hazardous air pollutants may also be deposited onto soil
or into water bodies, thereby affecting ecological systems
and eventually human health.
In addition to inhalation exposure from HAPs,
indirect exposures occur particularly through the
ingestion of food. Some of these HAPs (like mercury)
can bio-accumulate in body tissues and magnify up the
food web with each level accumulating the toxics and
passing the burden along to the next level. Top
consumers in the food web, usually consumers of large
fish, may accumulate chemical concentrations many
millions of times greater than the concentrations present
in the water. As a result, fish consumption advisories
have been issued in hundreds of water bodies nationwide,
including the Great Lakes. Adverse effects range from
immune system disease and reproductive problems in
wildlife to subtle developmental and neurological
impacts on children and fetuses.
Ecological effects attributable to bio-accumulating
HAPs can be subtle or delayed in the onset. Effects such
as immune function impairment, reproductive problems,
and neurological changesall of which can affect
population survivalcan occur.
Data Sources and Limitations
Ambient concentration data for individual air toxic
pollutants is limited (both spatially and temporally) in
comparison to the long-term nationwide monitoring for
the six NAAQS pollutants. Therefore, this chapter
focuses on emission trends and relies on EPA's Toxic
Release Inventory (TR1) as the primary source of
comprehensive information on emissions of air toxics.
Authorized by the Emergency Planning and Community
Right to Know Act (EPCRA) of 1986, the TRI requires
facilities with 10 or more employees meeting thresholds
for manufacturing, processing or otherwise using listed
chemicals (including air toxics) to submit annual reports
to EPA on their releases. Data for the TRI has been
collected since 1987 and it is the only air toxics inventory
which is regularly updated. Consequently, the data from
the TRI are used in this report to provide an indication of
trends in toxic emissions.
While TRI is the only database available for
assessing air toxic emission trends, there are significant
limitations in the inventory's portrayal of overall HAP
emissions. First, facilities with Standard Industrial
Classification (SIC) codes outside the range of 20 to 39
(the manufacturing SIC range) are not required to report.
Therefore, HAP emissions from facilities such as mining
operations, electric utilities, and oil and gas production
operations are not represented in the TRI. In addition,
emissions from small manufacturing facilities (those with
fewer than 10 employees) as well as mobile, commercial,
residential, and consumer sources are not included in
TRI. However, comprehensive, single-year national
inventories for specific pollutants (prepared by EPA to
support special studies called for by the CAAA) have
demonstrated mat for some toxic air pollutants,
emissions from these excluded source categories can be
much more significant than those from the manufacturing
. sector.5 Furthermore, TRI data are self-reported by the
emitting facilities, and facilities are not required to
perform actual monitoring or testing to develop their TRI
estimates. As a result, the accuracy of the reported data
can vary from facility to facility and year to year.
Finally, the original TRI list only required reporting for
173 of the 189 HAPs identified in the CAAA.
Efforts are underway to enhance the TRI database by
expanding both the type of facilities that must report their
releases and the list of chemicals that must be reported.
Two of the 16 compounds omitted from the original TRI
list (acetophenone and ethylidene dichloride) will be
added in the 1994 reporting year. Also, nine additional
HAPs have been proposed for addition to the TRI.
However, there are no plans to add the remaining five
HAPs to the TRI because they are either produced in
quantities too low to meet the reporting thresholds or
emitted by sources which currently are not required to
report to the TRI. In summary, 173 of the 189 HAPs
(those included in the TRI data base) are included in the
analyses within this chapter. All references to HAPs
emissions in the following section are to the sum of these
compounds as reported in the TRI.
NATIONAL Am QUALITY AND EMISSIONS TRENDS REPORT, 1994
4-5
-------
Air Toxics Regulation and
Implementation Status
The downward trend in emissions of air toxics described
in Section 4.1 is expected to continue. The 1990 CAAA
greatly expanded the number of industries affected by
national air toxic emission controls, and the emission
reductions from these controls are just beginning to be
realized for some industries. Large industrial complexes
(major sources) such as chemical plants, oil refineries,
aerospace manufacturers, and steel mills are some of the
industries being controlled for toxic air pollution. Where
warranted, smaller sources (area sources) of toxic air
pollution such as dry cleaning operations, solvent
cleaning, and chrome plating are also affected. Within
the next 10 years, the air toxics program is projected to
reduce emissions of toxic air pollutants by well over one
million tons per year.
Emission Reductions Through Air Toxics Regulation
The regulation of air toxics emissions through the
process outlined in Section 112 of the 1990 CAAA,
referred to as maximum achievable control technology
(MACT) regulations, is beginning to achieve significant
emission reductions of HAPs as well as criteria
pollutants. As Figure 4.7 shows, MACT standards have
been promulgated for twenty-seven source categories as
of October, 1995. Sources are required to comply with
these standards within three years of the effective date of
the regulation, with some exceptions. In addition to the
reduction of 880,000 tons per year in HAP emissions
from these source categories, EPA also estimates that the
MACT standards will result in reductions in the
combined emissions of PM-10 (a criteria pollutant) and
volatile organic compounds (ozone precursors) of about
1,890,000 tons per year as shown in Figure 4-8.
The five MACT standards in Figure 4.9, which are
collectively responsible for the majority of the HAP
emission decreases, individually produce reductions
ranging from 38,000 to S 10,000 tons per year. The ten
MACT standards in Figure 4.10 reduce emissions of
hazardous air pollutants which have very significant
health impacts such as dioxin, chromium, lead, mercury,
cadmium, arsenic, coke oven emissions, 1,3-butadiene,
and benzene.
The specific pollutants whose emissions are reduced
by the MACT program are detailed in Table 4.1 and
further in the Table A. 16 in Appendix A. In Table 4.1,
HAPs controlled by each standard are designated by an
"x". Some of these HAPs are of particular interest to the
special studies discussed in the next section.
Special Studies
As required by the 1990 CAAA, EPA is also conducting
special studies to assess the magnitude and effects of air
toxics focusing on specific sources, receptors and
pollutants. Summaries of examples of such examinations
are presented below.
The Great Waters Study
The CAA, Section 112(m)(5), requires a report to
Congress every two years assessing the extent of
atmospheric deposition of HAPs and other pollutants to
the Great Lakes, the Chesapeake Bay, Lake Champlain
and coastal waters. The need for new regulations to
protect these water bodies will also be included in this
report.4 The pollutants of concern include nitrogen
compounds, mercury, pesticides, and other HAPs. There
are extensive research studies underway throughout this
program to provide new understanding of the
complicated issue of atmospheric deposition of air
pollution to water bodies. New scientific findings will be
incorporated into each biennial report and appropriate
regulatory recommendations will be made based on those
findings. The CAA provides the authority to introduce
new regulations or influence those under development in
order to prevent adverse effects as well as environmental
effects resulting from exposure to these pollutants.
Utility Air Toxics Study
As mandated by Section n2(n)(l)(A) of the 1990
CAAA, the EPA is studying HAP emissions from fossil
fuel fired (coal, oil and gas) electric utilities. EPA is also
studying the adverse health effects associated with those
emissions.4 A draft Utility Air Toxics Study Report
published in June 1995 identified 67 HAPs in the
emissions database. Based on a screening assessment, 13
HAPs were determined as priority for risk analysis.
From coal-fired utilities, five HAPs (mercury, arsenic,
chromium, hydrogen chloride, and hydrogen fluoride)
appear to be of greatest concern. From oil-fired plants,
three HAPs (arsenic, chromium, nickel) are at the top of
the list. The report predicts that in the next two decades,
there will be roughly a 30-percent increase in HAP
emissions from coal-fired utilities and roughly a 50-
percent decline in HAP emissions from oil-fired utilities.
These projections are primarily based on anticipated
4-6
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
energy demands and changes in fuel usage, but also
consider other factors such as expected controls. EPA
plans to complete the Utility Air Toxics Study in late
1995.
The Mercury Study
The Mercury Study Report to Congress is a
comprehensive study of mercury emissions from
anthropogenic sources in the United States. The report
assesses the effect on health and ecological systems from
mercury emissions and analyzes technologies to control
mercury emissions as well as the costs of such controls.
The study is mandated by section ,112 (n)(l)(B) of the
1990CAAA.4
For industrial or manufacturing sources that use
mercury in products or processes, the overall
consumption of mercury is generally declining.
Industrial consumption of mercury has declined by about
one-third between 1988 (1508 Mg) and 1993 (558 Mg).
Much of this decline is attributed to the elimination of
mercury as a paint additive and the reduction of mercury
in batteries. Manufacturing decreases are important
because emissions of mercury are more likely to occur
when products containing mercury are broken or
discarded. Based on trends in mercury use ,and
emissions, EPA predicts that manufacturing use of
mercury will continue to decline. Secondary production
of mercury will continue to increase as more recycling
facilities recover mercury from discarded products and
wastes. A significant decrease will occur in mercury
emissions from municipal waste combustors and medical
waste incinerators if the regulations proposed by EPA for
these source categories are fully implemented. Based on
predictions in energy demands and fuel usage, mercury
emissions from utility boilers are expected to increase.
The Mercury Study Report to Congress is due to be
submitted to Congress in December 1995.
The Specific Pollutants Strategy
The CAA, Section 112(c)(6), requires EPA to identify
the sources of 90 percent of air emissions of alkylated
lead compounds, polycyclic organic matter,
hexachlorobenzene, mercury, polychlorinated biphenyls,
2,3,7,8-tetraehlorodibenzofurans and 2,3,7,8-
tetrachlordibenzo-p-dioxin.4 The Agency is required to
develop a strategy to promulgate standards for these
sources by the year 2000.
The Urban Area Source Program
The CAA, Section 112(k), requires EPA to develop a
strategy that will subject the sources of HAPs emissions
in urban areas to standard controls and thereby reduce
cancer risk from those HAPs by 75 percent.4 Research to
determine which HAPs and sources will be included in
the strategy is currently under way.
Table 4-1: Major pollutants controlled by standards promulgated (1990-1995).
Dtetin,
faEEi
^flPJgrtttflP-
J&SL.
m-rfrfflfrftfc-Sfifo****!
"Ha*"* Btmk^thMy , L ffffffl
Stoae I G*s*w
^tfftixn 4 RCTte.B
ftj^p^KhiiaCcrateaayiUJI
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
4-7
-------
Sep-93 Feb-94 Nov-94 May-95 Oct-95
Oct-93 Jul-94 Feb-95 Jul-95
Major 1
i Area
Figure 4-7: Cumulative number of source categories with MACT standards promulgated (1990-1995).
1993
1994
1995
HAPs m PMlO&VOCs
Figure 4-8: Cumulative emission reductions from promulgated MACT standards (1990-1995).
4-8
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
600
500
400
I 1 300
200
100
Haz Organic NESHAP (HON)
Q Petroleum Refineries
Aerospace Manufacturing |§ Solvent Cleaning
Perchloroethylene Dry Cleaners
Figure 4-9: Emission reductions (greater than 5000 tons/year) from promulgated MACT standards (1990-1995).
6000
5000
4000
3000
j
MACT Source Categories
MarineTanfc Vessel H Stage I Gas Distribution ^ MagnelieTspeManur ^ CofcOvens Q Secondary Lead Ssnctten
Copnin S(criliz«ra | Muni Waslc Cambustois ^ Chromium ElectropUling jH Pol>incre& Resins II ^ Indus Cooling Towers
Figure 4-10: Emission reductions (less than 5000 tons/year) from promulgated MACT standards (1990-1995).
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
4-9
-------
References
1. As used in this report, estimates of air releases or emissions of "hazardous air pollutants" or "HAPs" refer to the
173 (of the 189) air toxics defined by the Clean Air Act that are included in the TRI, The term "TRI air releases"
refers to reported emissions of both HAP and non-HAP compounds to air. Finally, the term "total TRI releases"
represents all emissions of any pollutants (HAPs and non-HAPs) to any media (e.g., air, water).
2, 1993 Toxics Release Inventory, EPA-745-R-95-Q1G, U.S. Environmental Protection Agency, Office of Pollution
Prevention and Toxics, Washington, D.C. 20460, March 1995.
3. 1992 Toxics Release Inventory, EPA-745-R-94-001, U.S. Environmental Protection Agency, Office of Pollution
Prevention and Toxics, Washington, D.C. 20460, April 1994.
4. Clean Air Act Amendments of 1990, U.S. Code of Federal Regulations, vol. 42 sec, 7412(b)(2), 1990
5. National Air Pollutant Emission Trends, 1900-1994, EPA-454-R-95-011, U.S. Environmental Protection Agency,
Office of Air Quality Standards and Planning, Research Triangle Park, N.C. 27711
4-10 NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Chapter 5
Nonattainment
Areas
This chapter provides general information on geogra-
phical regions known as nonattainment areas. When
an area does not meet the National Ambient Air
Quality Standards (NAAQS) for one of the criteria
pollutants, it may be designated as nonattainment. The
Clean Air Act Amendments (CAAA) of 1990 further
classify nonattainment areas for ozone (O3), carbon
monoxide (CO), and particulate matter (PM-10) based
on the magnitude of an area's problem. Nonattainment
classifications may be used to specify which air
pollution reduction measures an area must adopt, and
when the area must reach attainment. The technical
details underlying these classifications are discussed in
part 51 of the Code of Federal Regulations. To move
into attainment status, a nonattainment area must meet
the NAAQS and fulfill all CAAA requirements. Table
5-1 shows the total number of nonattainment areas for
each pollutant and provides comparable statistics for
each year since the CAAA designations were
implemented. Note that transitional and incomplete
areas are excluded from these counts. Over the past
year, the total number of nonattainment areas dropped
by 13, with O3 having the greatest net reduction of 14
areas. The number of nonattainment areas for CO and
lead (Pb) declined by two, sulfur dioxide (SO2)
declined by four, and PM-10 declined by one, while the
nitrogen dioxide (NO2) count remained at one. It is
important to note that there are several areas that have
begun the redesignation process, but are still included
in these counts since their redesignations have not yet
been finalized. As of September 1995, there were 4
CO, 1-Pb, 2 PM-10, and 29 O3 nonattainment areas
with pending redesignation requests.
Figure 5-1 shows the location of the nonattainment
areas for each criteria pollutant. Figure 5-2 further
identifies the O3 nonattainment areas by degree of
severity. A "simplified" summary of nonattainment
areas can be found in Table A-l 1 in Appendix A. The
simplified list was created by combining geographic
areas that are in nonattainment for more than one
criteria pollutant. As of September 1995, there were
a total of 185 nonattainment areas on the simplified
nonattainment list. Roughly one-fourth of these areas
maintain nonattainment status for more than one
criteria pollutant. The areas on the simplified list are
shown alphabetically by state. A more detailed listing
is contained in the Coae of Federal Regulations, Part
81 (40 CFR 81). In Table A-l 1, the population totals
corresponding to each nonattainment area are based on
1990 Census figures. For nonattainment areas defined
as partial counties, only population totals for the
applicable portion were used if available; otherwise,
the entire county population totals are shown. When a
larger nonattainment area encompassed a smaller one,
double-counting the population was avoided by only
counting the population of the larger area. When two
Table 5-1: Nonattainment area counts for NAAQS pollutants.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
5-1
-------
[Alt] »~"-
AREAS DESIGNATED NONATTAINMENT
BY POLLUTANT
Dnjgnatod
Now; unduiM *im» *» not Mown.
Figure 5-1: Location of nonattainment areas for criteria pollutants.
nonattainment areas only partially overlapped, the
areas were counted as two distinct nonattainment areas
and the populations were added accordingly. There
are approximately 134 million people living in areas
currently designated as nonattainment.
Boundaries of nonattainment areas generally
coincide with those of Metropolitan Statistical Areas
(MSAs). MSAs are defined as areas comprising a
large population center with adjacent communities that
have a high degree of economic and social integration
with the urban center. MSA boundaries are appointed
by the U.S. Office of Management and Budget. MSAs
contain a central county and any adjacent counties with
at least 50 percent of their population in the urbanized
area. Although MSAs compose only 19 percent of the
land area in the United States, they account for almost
80 percent of the total population. Table A-12 in
Appendix A presents a summary of the highest air
quality levels measured in each MSA during 1994.
The 330 MSAs are listed alphabetically along with the
1990 population estimate. Concentrations above the
level of the respective NAAQS are shown in bold italic
type. Readers are cautioned that this summary is not
adequate in itself to numerically rank MSAs according
to their air quality. The monitoring data represent the
quality of the air in the vicinity of the monitoring site,
but may not necessarily represent urban-wide air
quality.
5-2
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Classified Ozone Nonattainment Areas
As of July 21.1995
Figure 5-2: O3 nonattainment areas by degree of severity.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
5-3
-------
5-4 NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Chapter 6
Selected Metropolitan Area Trends
While most of this report discusses air quality trends
on a national scale, there is a great interest in local air
quality trends. The Pollutant Standards Index (PSI) is
used as an overall assessment of air quality for any
given day. PSI values are reported in all metropolitan
areas of the United States with populations exceeding
200,000. Table A-13 in Appendix A lists the number
of PSI days greater than 100 for all criteria pollutants
[except lead (Pb)] in Metropolitan Statistical Areas
(MSAs). Table A-14, also in Appendix A, lists the
number of PSI days greater than 100 for ozone (O5)
only. Summary statistics of PSI trends are listed in
Table A-15 of Appendix A. Ten-year PSI trends are
based on daily maximum pollutant concentrations from
the subset of ambient monitoring sites that have
complete data for a minimum of eight out of the 10
years.
The Pollutant Standards Index
The Pollutant Standards Index (PSI) is computed for
particulate matter whose aerodynamic size is equal to
or less than 10 microns (PM-10), sulfur dioxide (S02),
carbon monoxide (CO), ozone (O3) and nitrogen
dioxide (NO2), and is based on their short-term
National Ambient Air Quality Standards (NAAQS),
Federal Episode Criteria, and Significant Harm Levels.
Pb is the only major pollutant not included in the index
because it does not have a short-term NAAQS, a
Federal Episode Criteria, or a Significant Harm Level.
The five PSI color categories and their respective
health effect descriptors are listed in Table 6-1. The
PSI is primarily used to report the daily air quality of
a large urban area to the general public. It is reported
simply as a number or a word, and is featured on local
TV or radio news programs and, in newspapers.
Usually the index is presented in a pictorial form as
shown in Figure 6-1.
The PSI integrates information from five major
pollutants across an entire monitoring network into a
single number that represents the worst daily air
quality experienced in an urban area. Criteria pollutant
concentrations (except Pb) are converted into a number
between zero and 500. The index is calculated by first
computing a separate sub-index for each pollutant with
data for the day, and then determining the highest PSI
of any pollutant. The pollutant with the highest index
is reported as the PSI for that day. Therefore, the PSI
does not take into account the possible adverse effects
associated with combinations of pollutants (i.e., syn-
ergism).'-2
A PSI value of 100 corresponds to the standard
established under the Clean Air Act (CAA), and a PSI
greater than 100 indicates that at least one criteria
pollutant exceeded air quality standards on a given day;
therefore, air quality would be in the unhealthful range
on that day. PSI values activate public health
warnings. For example, a PSI of 200 initiates a First
Stage Alert at which time sensitive populations (the
elderly, and persons with impaired respiratory
illnesses) are advised to remain indoors and reduce
physical activity. A PSI of 300 initiates a Second
Stage Alert at which time the general public is advised
to avoid outdoor activiiy.
The PSI was designed to protect the public from
acute health effects (24 hours or less) as opposed to
chronic health effects (months or years) experienced as
a result of poor air quality. PSI values do not directly
account for the amount of damage air pollutants can
cause to public welfare, namely animals, vegetation,
and materials such as building surfaces and statues.
However, increased PSI levels generally reflect
increased damage to the environment.
PSI estimates depend on the number of pollutants
monitored as well as the number of monitoring sites
where data is collected. The more pollutants and sites
that are available in an area, the better the estimate of
the maximum PSI for a given day. Ozone accounts for
the majority of days with a PSI above 100, but is
collected only at a small number of sites in each area.
However, since O3 concentrations are relatively
uniform over large areas, O3 data can be used to
estimate maximum pollutant concentrations. The
typical one-in-six day sampling schedule for most PM-
10 sites limits the number of days that PM-10 can
factor into the PSI determination. This limitation can
result in an underestimation of the PSI.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
6-1
-------
Summary of PSI Analyses
Of the five criteria poltutants used to calculate PSI,
CO, O3 PM-10, and SQ generally contribute to the
PSI. NO2 is rarely the highest pollutant measured
because it does not have a short term NAAQS and can
only be included when concentrations exceed one of
the Federal Episode Criteria or Significant Harm
Levels.
Figure 6-2 shows the trend in the number of PSI
days greater than 100 summed across the nation's 90
largest metropolitan areas (those cities with total 1990
population greater than 500,000). Because of their
magnitude, PSI totals for Los Angeles, CA and
Riverside, CA are shown separately. The long-term air
quality improvement is evident in this figure. Between
1985 and 1994, the total number of PSI days greater
than 100 decreased 35 percent in Los Angeles, 27
percent in Riverside, and 72 percent in the remaining
major cities across the United States,
Figure 6-1: Pollutant Standards Index
Table 6-1: Pollutant Standards Index values with pollutant concentration, health descriptors, and PSI colors.
pjpasspisppssajpsis^^
INDEX
VALUE
500 -
400 -
300
200
100
50 -
n
AIR
QUALITY
LEVEL *
SIGNIFICANT
HARM
EMERGENCY
WARNING
SQ%OF
I4AAQS
POLLUTANT LEVELS
PMio
(24*001)
US'"53
- 5DQ
0
SO,
(24-flolII)
ugftn3
- 2100 -
1600
- 365
0
CO
ewouri
pf₯n
- so -
... 40 .-
4tS
o
(1-fWuf)
pprn
0.5 -
0 2
ft -I-5
D
NO j
(MiwiJ
PPffi
_ 2.Q
_ 1 6 _
1 7
0 6
a
HEALTH
EFFECT
DESCRIPTOR
HAZARDOUS
VERY
UNHEALTHFUL
UNHEALTHFUL
MODERATE
GOOD
PSI
COLORS
RED
ORW46E
YELLOW
GREEN
BLUE
Ns incfes values reported al concentration levels below those speafel by 'Aleut Lever criteria.
k Annual primary
6-2
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
2,000
1,500
1,000
500
0
RIVERSIDE-SAN BERNARDINO, CA (27% DECREASE)
LOS ANGELES-LONG BEACH, CA (35% DECREASE)
ALL EXCEPT LA AND RIVERSIDE (72% DECREASE)
1985 1986 1987 1988 1989 1990 1991 1992 1993 1994
Figure 6-2: Total number of PSI days greater than 100 in the 90 largest cities.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
6-3
-------
References
I. Measuring Air Quality, The Pollutant Standards Index, EPA-451/K.-94-Q01, U.S. Environmental Protection
Agency, Office of Air Quality Planning and Standards, Research Triangle Park, NC, February 1994.
2. Code of Federal Regulations, 40 CFR Part 58, Appendix G.
6-4 NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, ! 994
-------
Chapter 7
International Air
Pollution Perspective
This chapter discusses air pollution emissions and
ambient concentrations for selected cities and countries
around the world. Because air quality standards and
goals often differ among countries, common statistics
have been selected for purposes of comparison.
However, it is important to note that trends observed
within a specific country are more accurate than com-
parisons of trends made between countries.
Emissions
Estimates of global and national pollutant emissions
vary widely. Discrepancies in definitions, estimation
methodology, and model inputs cause this variability,
though misreporting may also be a factor. In 1985, the
European Council of Ministers began a program called
CORINE (Coordination d'Information Environne-
mentale) to gather, coordinate, and ensure the consis-
tency of information on the state of the environment in
Europe.1 One of CORJNE's component projects was
CORINAIR, an air emission inventory. This inventory
was first conducted for the year 1985 for the 12
European Union (EU-12) countries namely, Belgium,
Denmark, France, former West Germany, Greece,
Ireland, Italy, Luxembourg, the Netherlands, Portugal,
Spain, and the United Kingdom. In 1990, coverage
was expanded to include additional European nations.
A standardized approach has enhanced the usefulness
of emission data for international comparisons albeit
for a limited number of countries and years. Data from
CORINAIR are used in this section wherever possible.
U.S. data are taken from National Air Pollutant
Emission Trends, 1990-1994; Canadian data are
generally from Environment Canada (1985 and 1990);
and additional emissions estimates are culled primarily
from reports of the Organization for Economic
35.000
30.000.
1970 m 1975 1980 B 1985
Canada France Hungary Japan Spain
CSFR FRG Italy Poland UK
USA
China, P.R. USSR
Figure 7-1: Emissions of sulfur dioxide from anthropogenic sources in selected countries, 1970 to 1990.
Source: CORINAIR, Environment Canada, OECD (1993), USEPA (1995). [Japan; 1985 data refer to 1986]
NATIONAL Am QUALITY AND EMISSIONS TRENDS REPORT, 1994
7-1
-------
3,500
3,000
n
1970 H 1975 | 1980 g 1985 H 1990
}-
21,000
18,000
Canada CSFR France FRG GDR Italy Netherlands UK
USA
Figure 7-2; Participate matter emissions from anthropogenic sources in selected countries, 1970 to 1990,
Source: CORINAIR, Environment Canada, OECD (1993), USEPA (1995)
Cooperation and Development (OECD) and the United
Nation Environment Program (UNEP).
Worldwide anthropogenic emissions of sulfur
oxides (SOX, reported as SO2) were reported by OECD
to be approximately 99 million metric tons per year in
the early 1990s,2 Emissions data for selected countries
between 1970 and 1990 are shown in Figure 7-1.
These countries account for over three-fourths of the
1990 emissions estimate. Mexico also has significant
emissions of SOX (based on their 1985 estimate of 6.5
million metric tons), but insufficient statistics are
available to chart any trend.3 Between 1970 and 1990,
SOX emissions decreased in most of the countries
shown in Figure 7-1. The People's Republic of China
is a notable exception; their sulfur dioxide emissions
increased 98 percent between 1975 and 1990, from
10.1 to 20.0 million metric tons. (Note: 1970 data are
not available.)4 The United States reduced SOX
emissions by almost eight million tons between 1970
and 1990, the largest reduction of the countries charted.
Another environmental data source estimated 1985
global anthropogenic emissions of sulfur oxides to be
approximately 160 million tons.5 The difference
between the 1985 and 1990 global SOX emission
estimates (61 million metric tons or 38 percent) likely
exaggerates actual global SOX emission reductions
during this period. The countries represented in Figure
7-1 collectively recorded a decrease of almost seven
percent between 1985 and 1990. This percent decrease
is probably a better representation of global SO,
emission reductions during this time frame.
In 1990, global emissions of suspended particulate
matter were approximately 57 million metric tons.6
Fossil fuel combustion was the greatest contributor to
this total. Despite increased coal combustion in many
industrialized countries, particulate emissions have
decreased. This is a direct result of cleaner burning
techniques.7 Except for Italy, particulate emissions in
the countries listed in Figure 7-2 decreased between
1970 and 1990. The United States, the Netherlands,
former West Germany, and the United Kingdom all
realized reductions of more than 50 percent.
Global anthropogenic emissions of nitrogen oxides
(NO,, reported as NO2) were approximately 68 million
metric tons in 1990.2 Table 7-1 provides 1985 and
1990 NOX emission data for the EU-12 countries plus
Canada and the United States. These countries account
for nearly two-thirds of the nitrogen oxides emitted
into the atmosphere as a result of human activities.
Although aggregate NO^ emissions for the EU-12
countries increased 26.5 percent during this period,
NOX emissions in the United States and Canada
remained relatively constant, increasing only 0.8 and
0.5 percent, respectively.
7-2
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Table 7-1: Emissions of nitrogen oxides from
anthropogenic sources in selected countries, 1985
and 1990 (1,000 metric tons).
Source; COMNAIR, Environment Canada, USEPA (1995)
In addition to tracking emissions of criteria
pollutants, an increasing number of national and
international environmental organizations also track
emissions of greenhouse gases. Water vapor, carbon
dioxide, methane, nitrous oxide, ozone, and chloro-
fluorocarbons (CFCs) are the most commonly refer-
enced greenhouse gases. These gases allow sunlight to
pass through the atmosphere, but trap and absorb the
energy radiated from the earth's surface (as does a
greenhouse). Rising concentrations of greenhouse
gases increase global temperatures and can adversely
affect sea levels and flora. Carbon dioxide (CO,),
methane (CH4), and CFCs have the greatest global
warming potential.8 Human activities are largely
responsible for the recent atmospheric build-up of
these gases. Five of the largest contributors to the
global emission total for each of these gases are shown
in Figure 7-3. In 1992, the United States signed and
ratified the Framework Convention on Climate
Change. This agreement seeks to develop
methodology for estimating sources and sinks of
greenhouse gases, as well as consistent measures of
greenhouse gases emissions. In 1970, global CO2
emissions (from energy use and industrial processes)
were approximately 15.6 billion metric tons. In 1991,
global CO2 emissions had increased to approximately
22.0 billion metric tons. The Middle East experienced
the largest gain during this period, more than
quadrupling their emissions.3
Former USSR 16%
China, P.R. 11%
Japan 5%
FRG 3%
U.S. 20%
Former USSR12%
India 12%
Japan 18%
U.S. 22%
China, P.R. 15%
Former USSR11
FRG 6%
Italy 4%
Others 44%
Carbon Dioxide
(Global emissions = 22 billion metric tons)
Others 48%
Methane
Others 39%
Chlorofluorocarbons
(Global emissions = 275 million metric tons) (Global consumption = 600 thousand metric tons)
Figure 7-3: Global anthropogenic emissions of greenhouse gases, 1990 source,- OECD (1991), USEPA (1994)
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
7-3
-------
Worldwide CFC consumption was about 600
thousand tons in 1990.8 Because CFCs deplete strato-
spheric ozone, the United States and other countries
have drastically curtailed their production over the past
decade. The United States' consumption of CFCs
decreased almost two-thirds between 1986 and 199Q.4
Although the most common CFC substitutes (per-
fluorinated carbons and partially halogenated com-
pounds) are not harmful to the stratospheric ozone
layer, they are extremely powerful greenhouse gases.3
Global anthropogenic emissions of methane were about
275 million tons in I990.8 Landfills are the largest
source of human-induced methane in the United
States.3
Ambient Air
Most countries regulate ambient concentrations of
pollutants to protect their citizens and the environment.
The averaging times, number of exeeedances, and units
for these regulations vary between countries. The
World Health Organization (WHO) has developed
recommended international guidelines for the six
criteria pollutants (see Table 7-2). In conjunction with
UNEP, WHO also established the ongoing Global
Environment Monitoring System (GEMS). GEMS is
an urban air pollution monitoring and assessment
program involving over 850 monitors in 46 countries
worldwide. The GEMS program intends to strengthen
urban air pollution monitoring and assessment
capabilities, improve the validity and comparability of
data, and provide global appraisals on concentrations
and trends of urban air pollutants. Sulfur dioxide and
particulate matter account for almost 75 percent of the
GEMS monitoring network.9 This portion of the
network (excluding the United States) is highlighted in
Figure 7-4 along with 1990 concentration data from the
GEMS/AIR program for selected cities around the
world. With almost 200 GEMS/AIR designated mon-
itors, the United States' portion of the GEMS/AIR
network is the most extensive of all participating
nations.
By the year 2000, almost half of the earth's
population are expected to be living in cities. The
urban air quality of 20 of the world's largest cities was
recently evaluated by UNEP/ WHO. The study con-
cluded that air pollution is widespread in all 20 urban
areas. Each city exceeded WHO guidelines for at least
one criteria pollutant, 14 cities exceeded at least two
WHO guidelines, and seven cities exceeded three or
Table 7-2: WHO health guidelines.
Guideline values for combined exposure to SO2 and SPM.
more. Mexico City exceeded WHO guidelines for all
six pollutants. Their sulfur dioxide, carbon
monoxide,particulate matter, and ozone pollution
levels were classified as serious problems, while their
lead and nitrogen dioxide pollution levels were
classified as moderate problems. Particulate matter
was the predominant air pollution problem afflicting
the 20 megacities. New York was one of only three
cities that normally met the particulate matter WHO
guideline. Sulfur dioxide and ozone were the next
most prevalent forms of air pollution.10 Of the six
criteria pollutants, ozone tends to be the least
monitored. A chart comparing the maximum pollutant
level of Oj at various world cities in 1991 is shown in
Figure 7-5.
7-4
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
IS&-
SULFUR DIOXIDE fS02] *RITH. !HD»*«i
MEAN 24 HOUR
CIT» COUNTRY (PPII) (Ppy|
U.S. Standard
Sao Paulo
Montreal
Toronto
Vancouver
Beijing
Shanghai
Cairo
Hessen
Tehran
Osaka
Tokyo
Auckland
Chiislchiiien
Jarczew
Wroclaw
Lisbon
Madrid
Caracas
Zagreb ,
Brazil
Canada
Canada
Canada
China, P.R.
China. P.R.
Egypt
Germany
Iran
Japan
Japan
New Zealand
New Zealand
Poland
Poland
Portugal
Spain
Venezuela
Yugoslavia
0.030
0.015*
0.008 *
0.007 '
0.006 '
0.047
0.042
0.014
0.007 '
0.059
0.047 *
0.049 "
0,001
0,002 .
0.010
0.027
0.016
0.012
0.009
0,025
0,140
0,032
0,045
0.040
0.018
0.201
0,123
0,063
0.032
0,091
0,099
0.099
0.004
0.008
0.052
0.070
0.035
0.025
0.012
0.076
PARTICULATE rTSPl
CITT
Eariier U.S.
Sao Paulo
Hamilton
Monlreal
Toronto
Vancouver
Beijing
Shanghai
Hessen
Hong Kong
Osaka
Tokyo
Christcnurch
Lahore
Zagreb
COUNTRY
Standard
Brazil
Canada
Canada
Canada
Canada
China, P.R.
China, P.R.
Germany
Hong Kong
Japan
Japan
New Zealand
Pakistan
Yugoslavia
OEOU.
KGAN
75
24
64
45
64
37
390
263
32
as
47
55
11
386
118
:NDH>X
H HOUR
260
SO
201
110
201
77
1322
753
74
249
154
256
559
685
308
TSP
Nation Coot HiUan Cout
Canada
(nda
dim
Agerfra
UK
40 Canada
23 Aperlm
21 Owe
16 Japan
12 Cduitia
43
22
20
18
15
" bdicaies daia dil not meel ARS summary criteria
Figure 7-4: GEMS: 1990 sulfur dioxide and particulate matter monitors location and sample data.
[Monitors are located in shaded countries (317 SO2 monitors in 44 nations; 300 particulate matter monitors in 41 nations).
Note that South Korea, Austria, Germany, and the Netherlands only monitored SO2; Luxembourg only monitored
particulate matter,] Source: AIRS, USEPA
Mexico City, Mexico
Sao Paulo, Brazil
Sydney, Australia
U.S. Standard
Toronto, Canada
Barcelona, Spain
Montreal, Canada
Ottawa, Canada
Hong Kong
Calgary, Canada
Vancouver, Canada
London, England
Helsinki, Finland
204
(parts per billion)
0
50
100
150
200
Figure 7-5: Maximum daily average ozone levels at selected world cities, 1991.
Source: Environment Canada, USEPA, UNEP (1992). [Note: Mexico City & Sao Paulo data are approximate.]
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
7-5
-------
References
1. National Air Pollution Trends, 1900-1994, EPA-454/R-95-011, USEPA, Office of Air Quality Planning and
Standards, Research Triangle Park, NC 277! 1, 1995.
2. "The State of the Environment," OECD, Published by the Organization for Economic Cooperation and
Development, Paris, 1991.
3, National Air Pollution Trends, 1900-1993, EPA-454/R-94-027, USEPA, Office of Air Quality Planning and
Standards, Research Triangle Park, NC 27711, 1994.
4, "Environmental Data Report 1993-1994," UNEP, UNEP/GEMS Monitoring and Assessment Research
Center, London, United Kingdom, Blackwell Publishers, Oxford, England, 1993.
5. "The Environment in Europe and North America: Annotated Statistics 1992," United Nations Statistical
Commission and Economic Commission for Europe Conference of European Statisticians Statistical
Standards and Studies, Published by the United Nations, New York, 1992.
6. "The State of the Environment 1972-1992," UNEP, UNEP/GCSS HI/2, Published by the United Nations
Environment Program, Nairobi, Kenya, 1992.
7. "Urban Air Pollution," UNEP, 199la, UNEP/GEMS Environment Library No. 4, Published by United
Nations Environment Program, Nairobi, Kenya, 1991.
8. "OECD Environmental Data-Compendium 1993," OECD, Published by the Organization for Economic
Cooperation and Development, Paris, 1993.
9. "GEMS/AIR Air Quality Atlas", USEPA/UNEP/WHO, Office of Air Quality Planning and Standards,
Research Triangle Park, NC 27711, 1994.
10, "Urban Air Pollution in Megacities of the World," UNEP/WHO, 1992a, Blackwell Publishers, Oxford,
England, 1992.
7-6 NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Appendix A;
Data Tables
NATIONAL Am QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-l
-------
Table A-1. Trend Statistics Used in the 1994 Trends Report - Summary Statistics
STATISTIC UNITS SITES PERCENTILE
1985
1986
CARBON
2nd Max. 8hr. PPM 328 95th
90th
75th
50th
25th
10th
5tti
Arith. Mean
12.8
11,3
8,5
6.3
4.8
3.6
3.0
6.9
12.4
11.1
6.9
6.5
4,9
3.5
2.9
7.1
1iB7
1988
1989
1990
1991
1892
1993
1994
MONOXIDE
11.9
9.9
8.3
6.3
4.7
3.6
3.0
6.7
11.3
10.0
7.7
6.1
4,4
3.4
3.0
6.4
11.0
9.7
7.8
6.0
4.4
3.5
2.8
6.3
10.5
6.8
7,1
5.5
4.3
3,1
2.6
5.9
9,7
8,6
6,9
5.2
3.8
3.0
2.5
5.5
8.6
7.9
6.4
4.9
3.7
2.6
2.5
5.2
B.1
7.3
5,8
4.7
3.6
2.9
2.3
4.9
8.3
7.6
6.1
4.9
3.8
2.8
2.3
5.0
LEAD
Max. Qtr UG/M3 197 95th
90th
75th
50th
25th
10th
5th
" " Arith, Mean
0.71
0.56
0.37
0.22
0.14
0.09
0.07
0,29
0.43
0.33
0.21
0.14
0.09
0.06
0.05
0.18
0.41
0.24
0.15
0,09
0.06
0.04
0.03
0.16
0,30
0,21
0.11
0.07
0,04
0.02
0,02
0.11
0.23
0.16
0.10
0.06
0.04
0,03
0,02
0.08
0.26
0.16
0.08
0,05
0.03
0.02
0.01
0.08
0.19
0.14
0.06
0.04
0.02
0.01
0.01
0.06
0,15
0,11
0.05
0.03
0.02
0.01
0.01
0.05
0.14
0.09
0.05
0.03
0.02
0.01
0.01
0.05
0,14
0.08
0.05
0.03
0.02
0.01
0.01
0.04
NITROGEN DIOXIDE
Arith. Mean PPM 205 95th
90th
75th
50th
25th
10th
5th
Arith. Mean
0.043
0.037
0.028
0.021
0.014
0.007
0.004
0.022
0.045
0.035
0.027
0.021
0.014
0.007
0.004
0.022
0.043
0.038
0.028
0,021
0,015
0.006
0.004
0.022
0.046
0.037
0,028
0,022
0.014
0,008
0.004
0,022
0,043
0.035
0.028
0.021
0.014
0.007
0.003
0.022
O.O41
0.034
0.026
0.020
0,013
0.007
0,004
0.020
0.041
0.033
0.027
0,020
0,012
0.007
0.003
0.020
0.039
0.033
0.025
0.019
0.013
0.007
0.004
0,020
0.037
0.033
0.025
0.019
0.013
0.006
0.004
0.019
0.040
0.034
0.026
0.020
0.013
0.006
0.004
0,020
OZON6
2nd Max. 1hr. PPM 549 95th
90th
75th
50th
25*
10th
5th
" " " Arith. Mean
0.210
0.170
0.134
0.113
0,099
0.089
0.080
0.124
0.1 BO
a 160
0.130
0.113
0.099
0.089
0.080
0.120
0.183
0.168
0.140
0.118
0,105
0.091
0.087
0,126
0.210
0.181
0.154
0.130
0.111
0.097
0.08B
0.136
0.190
0.155
0.126
0.109
0,097
0.087
0.080
0,117
0.180
0.150
0.122
0.108
0,096
0.085
0.077
0.114
0.178
0.150
0,127
0.110
0.097
0.083
0.078
0.116
0,160
0.136
0.114
0.100
0.091
0.083
0.078
0.107
0.1BO
0.140
0.120
0.105
0.092
0,081
0.077
0.110
0.156
0.135
0.1 18
0.105
0.094
0,083
0.077
0.109
A-2
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Table A-1. Trend Statistics Used in the 1994 Trends Report - Summary Statistics
#of
STATISTIC UNITS SITES PERCENTILE
1986
1986
19S7
1988
1989
1990
list
1992
1993
1994
PMiO
VWd. Arith. Mean UG/M3 748 95th
90th
75th
50th
25th
10th
5th
" Arith. Mean
. SUliEUR
Arith. Mean PPM 475 95th
90th
75th
50th
25th
10th
5th
" " " Artth. Mean
2nd Max. 8hr, PPM 475 95th
90th
75th
50th
25th
10th
5th
" " " Arith. Mean
0.0198
0.0164
0.0121
0.0087
0.0054
0.0026
0.0016
0.0092
0.0962
0.0748
0.0557
0.0405
0.0252
0.0122
0.0080
0.0438
0.0177
0.0152
0.0122
0.0034
0,0054
0.0023
0.0016
0.0030
0.1000
0.0767
0.05B5
0.0397
0.0260
0.0115
0.0076
0.0440
53.S
4S.8
38,2
31.6
26.7
22.0
1B.2
35.4
56.2
45.0
37.2
30.9
26.S
22.0
18.S
33.2
47.0
40.2
34.6
28.4
23.9
19.5
16.6
29.9
46.5
40.1
33,8
28,5
24.2
19.6
16.3
29.8
42,6
37.2
31.4
26.1
22.2
18.3
15.0
27.3
41.7
38.6
30.5
25.8
21.4
17,8
14.8
26.5
40.0
36.9
31.0
25.8
21.5
17.7
14,3
26.6
DIOXIDE -.. . -;;.;. ..:=''.;;_ '. .;'!' ;'
0.0169
0.0149
0.0116
O.OOB2
0.0053
0.0023
0,0015
0.0088
0.0855
0.0702
0.0515
0.0382
0.024B
0.0103
0.0065
0.0406
0.0182
0.0152
0.0116
0.0084
0.0055
0.0026
0.0018
0,0089
0.0840
0.0714
0.0550
0.0401
0.0260
0.0134
0.0088
0.0430
0.0176
0.0149
0.0114
0.0081
0.0051
0.0024
0.0017
0.0086
0.0866
0,0729
0.0515
0.0386
0.0244
0.0126
O.OOB4
0.0408
0.0161
0.0138.
0.0105
0.0076 '
0.0046
0.0023
0.0016
0.0080
0.0748
O.OE26
0.0477
0.0332
0.0210
0.0103
0.0073
0,0367
0.0154
0.0131
0.0100
0.0075
0.0047
0.0022
0.0017
0.0078
0,061)3
0,0573
0,0443
0.0321
0,0210
0.0099
0,0076
0.0340
0.0142
0.0125
0.0096
0.0068
0.0044
0.0021
0.0016
0.0073
0.0691
0,0551
0.0431
0.0305
0.0191
0.0107
0.0073
0.0330
0.0145
0.0123
0.0092
0.0067
0.0042
0.0023
0.0016
0.0072
0.0657
0.0553
0.0408
0.0279
0.0183
0.0099
0.0061
0.0314
0.0137
0.0120
0.0091
0.0065
0.0041
0.0022
0.0016
0.0069
0.0683
0.0557
0.0431
0.0305
0.0191
0.0092
0.0061
0.0327
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-3
-------
Table A-2. National Carbon Monoxide Emission Estimates, 1985-1994 (thousand short tons)
Source Category
File! Combustion
Electric utilities
Steam generated fossil-fuel
Other [ic and gt]
Industrial
Other fuel combustion
Residential wood
Other
Industrial Processes & Related
Chemical & allied product mfg
Metals processing
Petroleum & related industries
Other industrial processes
Solvent utilization
Storage & transport
Waste disposal & recycling
Transportation '-;,
Highway vehicles
Off-highway
N3hjra!'-Sourc|S ''" ' - ." .'"; '""
.M'&peilSti&nis'''; '. ' ..:
Wildfires
Prescribed burning
Other
1985
8,486
292
NA
MA
670
7,528
7,232
293
5,274
1,845
2,223
462
694
2
49
1.941
: W.94
77,387
13,706
.'.':,".£',
y-; 7;S?r.
2,957
4,300
63B
1986
7,548
291
NA
NA
650
6,607
6,316
291
5(151
1,853
2.079
451
715
2
51
1,916
/87j33Q^
73.347
13,984
~":'C-'°^
'''.$$&?:
2,271
4,300
683
1987
6,960
300
NA
NA
649
6,011
5,719
292
SidOl
1,798
1,984
455
713
2
50
1,850
,8S;38j,r
71,250
14,131
' ':'.' '-^'.
': «;82Q ':
3,795
4,300
725
1988
7,372
313
NA
NA
669
6,390
6,086
303
5,227
1,917
2,101
441
711
2
56
1,806
;.8Sy58T:-
71,081
14,500
:;.. X;
'v:t?;wa :
10,709
4,300
854
1989
7,441
31 i
NA
NA
672
6,450
6,161
288
5,266
1.925
2.132
436
716
2
55
1,747
ASM;.
66,050
14,518
:'""; Q
-?'*vi21
3,009
4,300
813
1990
5,0i4
314
NA
NA
677
4.072
3,781
291
5,228
1,940
2,080
435
717
2
55
1,686
- ''77,500;--:;
62,858
14.642
;':/'&.
- J:t,im .
6,079
4,300
794
1991
5;35S
315
303
12
667
4,373
4,090
283
5,114
1,944
1,992
412
710
2
54
1.701
.':76;6'7-§:;.
62,074
14.60-
: -'C-.
" 8;;530:
3.439
4,300
791
1992
5,601
313
302
11
672
4,616
4,332
283
5,193
1,964
2,044
410
719
2
55
1,717
--74J759--
59.859
14,iOO
,: X. ' ". tf: .
- ; 6,774'"''
1,674
4,300
BOO
1993
4,854
323
311
12
670
3,961
3,679
283
.5,27-7
1,998
2,091
398
732
2
56
1,732
= 75,4=71 '
60.202
15,269
Q
6,700
1,586
4,300
814
1994
4,884
325
313
12
671
3,888
3,607
281
5.414
2,048
2,166
390
751
2
58
1,746
76.727
61,070
15,657
0
9,245
4,115
4,300
831
Total
NA = Not Available
. 108;<«2
A-4
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Table A-3. National Lead Emission Estimates, 1985-1994 (short tons)
Source Category
Fuel Combustion
Electric utilities
Industrial
Other fuel combustion
Industrial Processes & Related
Chemical & allied product mfg
Metals processing
Petroleum & related industries
Other industrial processes
Solvent utilization
Storage & transport
Waste disposal & recycling
Transportation
Highway vehicles
Off-highway
Natural Sources
Miscellaneous
198S
515
64
30
421
3,402
118
2,097
0
316
0
0
871
16,207
15,978
229
o
0
1986
516
69
25
422
2,972
108
1,820
0
199
0
0
844
3,808
3,589
219
0
0
1987
510
64
22
425
3,004
123
1,835
0
202
0
0
844
3,343
3,121
222
0
. 0
1988
511
66
19
426
3,090
136
1,965
0
172
0
0
817
2,911
2,700
211
0
0
1989
505
67
18
420
3,161
136
2.088
0
173
0
0
765
2,368
2,161
207
0
0
1990
soo
64
18
418
.3,278
136
2,169
0
169
0
0
804
1.8B8
1,690
197
0
0
1991
495
61
18
416
3,081
132
1,975
0
167
0
0
807
1,704
1,519
186
0
0
1992
491
59
18
414
2,771
93
1,775
0
56
0
0
847
1,637
1,444
193
0
'"'" 0
1993
491
61
15
415
2,868'
96
1,887
0
54
0
0
829
1,580
1,401
179
0
0
1994
493
63
15
415
2-868
93
1,873
0
55
0
0
847
11996
1,403
193
0
: 0
Total
20,124 7,296 6,857 6,513 6,034 5,6i6 5,279 4,839 4,938 4,95f
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-5
-------
Table A-4. National Nitrogen Oxides Emission Estimates, 1985-1994 (thousand short tons)
Source Category
Fuel Combustion '
Electric utilities
Steam generated tosstMuel
Other [ic and gl]
Industrial
Other fuel combustion
Residential wood
Other
IfldustriaKPrpcesses & Related
Chemical & allied product mfg
Metats processing
Petroleum & related industries
Other industrial processes
Solvent utilization
Storage & transport
Waste disposal & recycling
Transportation ;-
Highway vehicles
Off-highway
Nkfu'ral'Sources.- ." " ""',
Miscellaneous: "-.
Wildfires
Prescribed burning
Other
1985
10.S36
6,916
NA
NA
3,209
712
88
624
891
262
87
124
327
2
2
87
10^823
8.089
2,734
: . ' d
:,309
142
153
14
1986
10,668
6,909
NA
NA
3,065
694
77
618
873
264
80
109
32B
3
2
B7
10,550
7,773
2,777
: ' d.-
257
89
153
15
1987
10.897
7.128
NA
'NA
3,063
706
69
635
840
255
75
101
320
3
2
85
10,31.5
7,651
2,664
; . 0
-'- 351
1B2
153
16
1988
11,437
7,530
NA
NA
3,187
740
74
668
860
274
82
100
315
3
2
85
: 10,575
7,661
2.914
.'. | 0-.
726'
554
153
19
1989
11,552
7,607
NA
NA
3,203
736
75
661
B51
272
83
97
311
3
2
B4
10,526
7,682
2,844
.';: /Q
292
121
153
18
1990
11.483
7.516
NA
NA
3,258'
712
46
666
BSD
276
81
100
306
2
2
82
10(331
, 7.4BB
2,843
' ' 0
373
203
153
17
1991
11,382
7,488
7,432
56
3,175
719
SO
670
838
278
78
97
297
2
2
93
10,170
7.373
2,796
.0
283
112
153
17
1992
11,421
7,475
7,422
32
3,216
730
53
678
852
284
80
96
305
3
3
83
10.325 '
7,440
2.8B5
-'" - 0'
249
78
153
18
1993
11.696
7.773
7,717
56
3,197
728
45
681
S66
286
81
95
315
3
3
84
. 10.485
7,510
2.985
6.
219
47
153
18
1994
11.728
7.795
7.740
55
3,206
727
44
683
S88
291
84
95
328
3
3
85
10.624
7,530
3.095
0
374
203
153
18
Toiii:
NA = Not Available
22;409 23,618 23,1221 23036 23,672 2Z;B47 :23,276 23,616
A-6
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, i 994
-------
Table A-5. National Volatile Organic Compound Emission Estimates, 1985-1994 {thousand short tons)
Source Category
Fuel Combustion
Electric utilities
Steam generated
Other (ic and gt)
Industrial
Other fuel combustion
Residential wood
Other
Industrial Processes & Related
Chemical & allied product mfg
Metals processing
Petroleum & related industries
Other industrial processes
Solvent utilization
Storage & transport
Waste disposal & recycling
Transportation
Highway vehicles
Off-highway
Natural Sources
Miscellaneous
Widflres
Prescribed burning
Other
1985
1,570
32
NA
NA
134
1,403
1,373
31
12,282
1,358
76
703
390
5,699
1,747
2,310
11>384 .
9.376
2,008
"'. ;: 0
562
283
179
100
1986
1,39i
34
NA
NA
133
1,230
1,199
31
12,138
1,412
73
666
395
5,626
1,673
2,293
10j912
8,874
2,039
.;,"" Q.:
544 ;
2S9
179
106
1987
1,282
34
NA
NA
131
1.117
1,085
32
12,329
1.410
70
655
394
5,743
1,801
2,256
10,515
8.477
2,038
"-"' 0:
- : : 652:
361
179
112
1988
1,361
37
NA
NA
136
1,188
1,185
33
12,737
1,513
74
645
408
5,945
1,842
2,310
10,396
8,290
2,106
0
'-,:1,227- -
918
179
130
1989
1.371
37
NA
NA
134
1,200
1,169
31
12,62i
1,506
74
639
403
5,964
1J53
2,290
' 9i;295:''
7.192
2.103
0:
;' '-eaai
335
179
124
1990
919
36
NA
NA
135
749
718
31
12,638
1,526
72
643
401
5.975
1.759
2,262
8,974:
6,854
2,120
'.:->. o
'. '-1-1Q69.
768
179
122
1991
977
36
35
1
135
807
776
30
12(537
1,533
69
634
396
5,918
1,720
2,265
' - ;8;62l:->.
6,499
2,122
H> .*.:
- -: -741 .
440
179
121
1992
1,022
35
34
1
135
853
822
31
132,702
1,546
72
638
403
6,031
1,745
2,268
' -:;8;23T
6,072
2,159
^ -C--0-..
-." '" :*66
164
179
123
1993
899
36
35
1
134
729
698
30
12,881^
1,557
74
631
406
6,156
1,757
2,271
8;3Qi
6,103
2,206
'-I' - °
: '-'&& '
212
179
125
1994
B86
36
35
1
135
715
684
30
131054
1.577
77
630
411
6,313
1,773
2,273
8,5*9
6,295
2,255
, '-' 0
" '685'
379
179
127
Total
NA = Not Available
2SJ99 24,931 24,777 25,720 23^34 23;6M> 22;8?6 22^22 22ii76 23}17*
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-7
-------
Table A-6. National Particulate Matter (PM-10) Emission Estimates, 1985-1994 {thousand short tons)
Source Category
Fuel Combustion
Electric utilities
Steam generated fossil-fuel
Other [ic and gt]
Industrial
Other
Residential wood
Other
industrial Processes & Related
Chemical & allied product mfg
Metals processing
Petroleum & related industries
Other industrial processes
Solvent utilization
Storage & transport
Waste disposal & recycling
Transportation ;
Highway vehicles
Off-highway
Total'- - -' ' .'. . , . . . ';
Table A-7. Miscellaneous
Source Category
Miscellaneous :
Fugitive dust
Unpaved roads
Paved roads
Construction
Mining & querying
Agricultural tilling
Olher Combustion
Wildfires
Prescribed burning
Other
1985
1,538
284
280
4
245
1,009
959
50
952
57
142
32
382
2
59
278
-A 731 ,-
363
368
5,220
1986
1,419
288
284
4
243
888
837
51
945
58
132
31
390
2
58
274
...' 729..
356
372
; 3,092
& Natural Source
1985
37,903
36,742
11.830
5,071
12,670
337
6,833
1,167
308
447
412
1986
37,186
36,065
11.773
5,257
11.825
312
6,899
1.101
226
447
427
1987
1,333
284
280
4
238
811
758
53
921
57
126
30
364
2
56
265
710
360
350
2,964
PM-10
1987
37,518
36.203
11,184
5,526
12,121
375
6.996
1,315
389
447
479
1988
1,383
279
275
4
242
862
807
55
929
61
136
29
385
2
56
259
756.'.
369
387
3,067
1989
1,383
273
269
4
241
869
817
52
913
62
137
28
377
2
56
251
- '?39
367
372
3,035
1990
1,075
282
278
4
240
553
501
51
900
62
136
28
374
2
57
242
729
357
372
2,704
1991
1,076
248
244
4
234
593
542
51
881
62
130
27
362
2
55
244
717
349
w
2,674
Emission Estimates, 1985-1994
1988
39,616
37,539
12,563
5,893
11,662
344
7,077
2,077
1,086
447
544
1989
37,504
36.199
11,849
5,767
11,269
391
6,923
1,305
300
447
558
1990
37i232
35,655
12,311
5,967
10,044
350
6,983
1,578
590
447
541
1991
36,188
34,870
11,911
5,967
9,672
367
6.952
1.319
333
447
538
1992
1,109
247
243
4
236
626
574
51
894
63
133
27
368
2
56
246
722
343
379
2,725
1993
1,041
268
264
4
234
539
488
51
910
63
136
27
377
2
57
248
716
321
395
2,666
1994
1.033
26S
262
4
237
52S
478
51
932
64
141
26
390
2
59
250
722
311
411
2,688
(thousand short tons)
1992
36,371
35,207
11,527
5,942
10,543
357
6,838
1,164
171
447
546
1993
38,636
37,480
13,215
6,077
10,993
358
6,837
1,157
152
447
557
1994
40,766
39,325
13,497
6,343
12.397
372
6,716
1.442
424
447
571
Natural Sources (Wind Erosion)
Total
4,047 10,324 1,577 18,110 12,101 4,362 10,095 4,626 1,978 2,593
41,956 47,490 39,095 57,727 49,605 41,594 46,234 40,997 40,614 43,360
A-8
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Table A-8. National Sulfur Oxides Emission Estimates, 1985-1994 (thousand short tons)
Source Category
Fuel Combustion
Electric utilities
Steam generated
Other (ic and gt)
Industrial
Other fuel combustion
Residential wood
Other
Industrial Processes & Related
Chemical & allied product mfg
Metals processing
Petroleum & related industries
Other industrial processes
Solvent utilization
Storage & transport
Waste disposal & recycling
Transportation
Highway vehicles
Off-highway
Natural Sources,
Miscellaneous '. .
Widfires
Prescribed burning
1985
20,021
16,273
MA
NA
3,169
579
13
566
2,467
456
1,042
505
425
1
4
34
730
522
208
o
11
6
6
1986
19;428
15,701
NA
NA
3,116
611
11
600
2i25e
432
888
469
427
1
4
35
748
527
221
;- "'"0
'- 9
3
6
1987
19,445
15,715
NA
NA
3,068
662
10
652
1,976
425
648
445
418
1
4
35
771 :
538
233
- ' .: :ft-'
13
7
6
1988
19,761
15,990
NA
NA
3,111
660
11
650
2,052
449
707
443
411
1
5
36
806
553
253
0
.: 'W-°
22
6
1989
19,927
16,218
NA
NA
3,086
624
11
613
2.010
440
695
429
405
1
5
36
837
570
287
-;-- 0
10
5
6
1990
19,698
15,898
NA
NA
3,106
595
7
586
1,985
440
663
440
401
1
5
36
836
571
26S
'--. . b
T4;:
8
6
1991
19,295
15,788
15,754
35
2,915
592
7
585
1,828
440
633
422
391
1
5
36
''.836-.-
570
266
i. o :
10
4
6
1992
18,019
15,418
15,386
32
3.002
599
8
592
1,957
447
650
417
401
1
5
37
851
578
273
0
9
3
6
1993
18,732
15,181
15,159
32
2,942
599
6
593
1,982
450
667
409
. 413
1
5
37
. 795'-;:
517
278
0
'-'' 8
2
6
1994
18;497
14,869
14.836
34
3,029
599
6
592
2,029
457
692
406
431
1
5
37
579
235
283
i 0
14
B
6
Total
NA = Not Available
23,230 22,442 22,204.22,647 22J8S 22^33 22,018 21,836 21,617 21,-HB
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-9
-------
Table A-9, Long-term Air Quality Trends: Plotting Points, 1975-1994
Year
CO
2nd Max. 8hr.
PPM
N02
Arith. Mean
PPM
OZONE
2nd Max, 1hr.
PPM
PB
Max. Qfr
UG/M3
PM-10
Wtd. Arith. Mean
UG/M3
SO2
Arith. Mean
PPM
1975-84 (141 sites)
(40 sites)
(149 sites) (43 sites) TSP{1610 sites) (149 sites)
1975
1976
1977
1978
1979
1980
1981
1982
1963
1984
12.4
11.7
11.1
10.4
10.1
9.3
9.0
8.1
8.2
8.1
0.0300
0,0290
0.0290
0.0300
0.0290
0.0270
0.0260
0.0240
0.0240
0.0250
0.152
0.151
0.150
0.154
0.135
0.138
0.126
0.124
0.138
0.124
1.730
1.740
1.850
1.670
1.380
1.020
0.830
0.510
0.390
0.370
72.3
73.7
73.1
71.8
71.8
72.5
66.7
5S.4
56.7
57.3
0.0145
0.0148
0.0130
0.0123
0.0119
0.0109
0.0102
0.0094
0.0091
0.0092
1985-94 (328 sites)
(205 sites)
(549 sites) (197 sites) PMriQ(748 sites)
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
6.9
7.1
6.7
6.4
6.3
5.8
5.5
5.2
4.9
5.0
0.0217
0.0218
0.0217
0.0220
0.0216
0.0204
0.0203
0.0197
0.0192
0.0200
0.124
0.120
0.126
0.136
0.117
0.114
0.116
0.107
0.110
0.109
0.290
0.180
0.160
0.110
0.082
0.081
0.059
0.051
0.046
0.044
33.4
33.2
29.9
29.8
27.3
26.5
26.6
0.0092
0.0090
0.0088
0.0089
0.0086
0.0080
0.0078
0.0073
0.0072
0,0069
A-10
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Table A-10.
Air Quality Trend Statistics By Monitoring Location
STATISTIC UNITS
#01
SITES
LOCATION
19B5
1936 19B7
1988
1989
1990
1991
1992
1993
1984
CARBON MONOXIDE
2nd Max. 8hr. PPM
n it
tt n
Max. Qtr UG/M3
fi n
fi li
6
137
183
5
96
94
RURAL
SUBURBAN
URBAN
RURAL
SUBURBAN
URBAN
4.6
6.4
7.S
0,14
0,26
0.33
5.2 4.7
6,4 6.3
7.7 7.1
LEAD
0.07 0.04
0.16 0.13
0.21 0.2
3,9
5.9 '
6.9
0.03
0.09
0.13
3.6
5,9
6.8
0.04
0.08
0,09
3.2
5.4
6.3
0.03
0.07
0.1
3.0
5.1
6.0
0.02
0.05
0.07
3.2
4.B
5.5
0.02
0.04
0.06
2.7
4.7
5.1
0.02
0.04
O.OS
3.0
4.B
S.3
0.01
0.04
0.05
NITROGEN DIOXIDE
AriMi. Mean PPM
M It
fi IS
2nd Max. 1hr. PPM
11 !l
fi II
Wtd Arilh. Mean UG/M3
ii 11
»
36
94
71
155
25i
117
83
296
352
RURAL
SUBURBAN
URBAN
RURAL
SUBURBAN
URBAN
RURAL
SUBURBAN
URBAN
0,008
0.023
0,028
0.114
0.129
0,123
0.008 O.OOB
0,023 0.023
0,028 0.027
OZONE
0.112 0.115
0,125 0.132
0.119 0.125
PM10
o.ooa
0.023
0.027
0.127
0.143
0.133
27.8
33.87
34.31
O.OOB
0.023
0.027
0.111
0,122
0.114
28.35
33.34
34.11
O.OOB
0,022
0.025
0.110
0.119
0.109
25.8B
30.13
30.85
0.008
0.022
0.025
0.108
0.121
0.112
2S.3
29.92
30,86
0.006
0.021
0.025
0.102
0.112
0.103
23.26
27.63
28.21
0.007
0.020
0.024
0,106
0.114
0.104
21.92
26.88
27.48
0.008
0.021
0.025
0.104
0.113
0.106
21.6
26.93
27.71
Aritti. Mean PPM
SULFUR DIOXIDE
127 RURAL 0,0073 0.0073 0.0073 0.0074 0.0072 0.006B O.Q068 0,0065 0.0066 0,0063
190 SUBURBAN 0.0097 0,0094 o.ooso 0.0092 o.ooaa o.oosz o.ooao 0.0074 0.0072 o.oo?o
146 URBAN 0.0105 0.0103 0.0099 0.0101 0.0100 0.0091 O.OOSS O.OOSO 0.0077 0.0076
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-ll
-------
TABLE A-11.
SIMPLIFIED NONATTAINMENT AREAS LIST(a)
STATE
1 AK
2 AK
3 AK
4 AL
5 AZ
6 AZ
7 AZ
8 AZ
9 AZ
10 AZ
11 AZ
12 AZ
13 AZ
14 AZ
15 AZ
16 "AZ
17 .CA
18 CA
18 CA
20 CA
21 CA
22 CA
23 CA
24 CA
25 CA
28 CA
27 ' CA.
28 CA -
' 29 CA' "-.
at> CA
31 CA
32 CA
33 CA
34 CO
35 CO
36 . . CO
,»:. co'. -
. ae " CQ '
~3i --co: -
40 CO
41 CO
42 CO
43 CO
44 CT
48 DC-MD-VA
46 -DE- -.
.47 ";FL "
. . 46 -6A
- 49 ' -GA
60 <&>.-
51 GU
52 IA
53 ID
54 ID
55 ID
56 ID
57 ID
58 It
59 IL-IN
BO IN
61 IN
62 IN
S3 IN
64 IN
65 IN
68 KY
67 KY
68 KY
69 KY-1N
70 LA
AREA NAME(b)
Anchorage
Fairbanks
Juncau
Birmingham
Ajo
Bullhead City
Douglas
Mianii-Hayden
MorenEl
ttogataa
Paul Spur
Pajson
Phoenix
Ri'llilo
San Manuel
Yurna
CnTra
Coaehella Valley
Imperial Valley
' Laka-Tahoe StHJtfvShwe
Los Angetis-South Coasl Air Basin
Mammoth Lakes (In Mono Co.)
Mono Basin (in Mono Co.)
Monterey Bay
Owens Valley
- Sacramento Metro
SanDlego .
San Francisco-Oaltland-Sun Joso
San Joaniflri.yallBy ,-
Santa Baibara-Sarila Maiia-Lonipoc
Seartes Valley
Southeast Desert Modified AQMA
Ventura Co,
Aspen
Canon City
Cblo'raftxSprinQs -..,:.
;:BrajyW«&TUer.;;-; ' -:_ '-"- . .
. FbHCoifint-;:: .' -.';; ,
Limaf; :;" " - '
Lorigrrjoht. :
Pagosa Springs
Sleamboal Springs
Telluride
Greater Conneclicut
Washinglon
-Sussex:^ ' . - . . ' . .
-TampftSL Petiersburg-Clearwaler
Allanla; ;; .
Muacogea'Co. /
Plti PowerPlam
Tanguisson Power Plant
Musealine Co.
Boise
Bonner Co.(Sandpolnt )
Pinehurst
Poratello
Shostione'
Ofltesby *
Ghlcago-Gary-Lake County
Evanaville .
Marion Co.
Laponc Co.
Vermillton Co,
ViflO Co.
Wayne Co.
Boyd Co.
Lewnglon-Fayetle
Muhlenberg Co.
Louisville
Balon Rouge
POLLUTANT(c)
O3 CO SO2 PM10 Pb N02
1
1
1
1
1
2
1
1 1
1
1
1
1 1
1
1 1
1 t
.1 (e)
1 3
1
1
1
1
.''."-' '1 '
-. " . 1
1
1 1
1 1
1
1 '
- 1 - .
1
1
1
1 . - 1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1 . .
1
1
1 .
2 , 1
1
1
1
'1
1 ...
1
1
1
1 '
1
1
1
1
1
. - , , " . .
1 ' .
1
1
1
1
1
1
3
l (0
1
(a) -
POPULATION^)
(1000s)
130
41
1Z
751
6
5
13
3
8
19
1
5
2092
1
5
55
72
183
82
,30
13513
10 (Pop Mono Co.)
. (See Mono Co. above)
622
IB
183S
2498
3830
2742
370
31
' 3B4
669
5
13
.353
, - /leas-- .. - : -
1 . : tbs
' ' ;'"^f
52
1
7
1
2470
3924
113
16BB
2SS3
179
145
. (See Guam above)
40
205
27
2
61
1
4
78S6
165
ao
107
17
106
72
51
249
31
B34
582
A-12
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
TABLE A-11.
SIMPLIFIED NONATTAINMENT AREAS LIST(a) (cant.)
71
72
73
74
75
76
77
78
78
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
11O
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
STATE
LA
MA
MA-NH
MO
MD
ME
ME
ME
ME
ME
ME
Ml
Ml
Ml
MN
MM
MO
MO
MO-IL
MT
MT
MT
MT
MT
MT
MT
MT
MT
MT
MT
MT
NE
NH
NH
NJ
NM
NM
KM
NM
NV
NV
NV
NY
NY
NY
NY
NY
NY-NJ-CT
OH
OH
OH
OH
OH
OH
OH
OH
OH-KY
OH-PA
OR
- OR
OR
OR
OR
OR
OR
OR-WA
PA
PA
PA
PA
AREA NAME(b)
Lake Charles
Springfield (W. Mass)
Boston- Lawrence-Worcester
Baltimore
Kant and Queen Anne Cos,
Hancock and Waldo Cos.
Knox end Lincoln Cos.
Lewi aim-Auburn
Mitllnocfeet
Portland
Presque Isle
Detroit
Glands Rapids
Muskegon
Minneapolis-Si. Paul
Olmsled Co,
Dent
Liberty-Arcadia
SI. Louis
Bulls
Columbia Falls
Kalispell
Lame Deer
Lewis & Clark
Librjy
Mlssoula
Poison
Ronah
Thompson Fails
Wtiltcfish
Yellowstone
Douglas
Manchester
Ports rnoulMtaver-RaehesIer
Atlantic City
Albuquerque
Anthony .
Grant Co,
Suntend Pa*
Central Steploe Valley
Las Vegas
Reno
Albany-Schenectady-Troy
Buffalo-Niagara Falls
EssexCo. (While Mln,)
Jefferaon Co. ~
Pqughkeepsie
New.York-N. New Jersey-Long Island
Canton
Cleveland-Akron-Lorain
Columbys
Coshocton Co.
Gala Co.
Jefferson Co.
Lake Co.
Lucas Co.
Cincinnati-Hamilton
Young stown- Warren-Sharon
Grants Pass
Klamatti Falls
Lakeview
LaGrande
Medlbrd
Oak ridge
Springfield-Eugene
Portland- Vancouver AQM A
Aliocrna
Conewsngo Twp. (In Wairen Co, PA)
Erie
Harrisburg-Leoanon-Cartisto
POLLUTANT(C) POPULATION^
O3 CO S02 PM10 Pb N02 (IQOBis)
1 ..... 168
1 ..... 812
1 1 , . . 5500
11 .... 2348
1 ..... 52
1 ..... 80
1 ..... 67
1 ..... 221
1 ... B
1 ...... 441
1 . . 11
1 . . 1028
1 ..... 688
1 ...... 159
1.1,. 2310
..1 ... 71
1 . 1
1 . 6
1 . .
-------
TABLE A-11.
SIMPLIFIED NONATTAINMENT AREAS LIST(a} (cont.)
STATE
141 PA
142 PA
143 PA
144 PA
145 PA
146 PA
147 PA
148 PA-OE-NJ-MD
149 PA-NJ
150 PR
151 Ri
1S2 TN
153 TN
154 TN
155 TN
1S6 TN
157 TN
158 TX
159. TX
160 TX
161 TX
182 UT
163 UT
164 UT
165 UT
188 VA
167 VA
168 VA
.169 . WA -
170 WA
171 WA
172 WA
173 WA
174 Wl
175 Wl
176- Wl
177 W| '.
178 Wl
179 Wl
180 Wl
181 Wl
182 WV
183 WV
184 WV
185 WY
AREA NAME(b)
Johnstown
Lancaster
Pittsburgh-Beaver Valley
Reading
Scranlon-Wlkes-Borre
Warren-Pleas.-eiade (In Wamen Co)
Yo*
PhJIadalphia-WlmlnQton-Tronton
Altenlcrwn-BetWehem-Easton
GuaytiaboCo.
Providence (all of Rl)
Betilon Co.
Fayette Co,
Humphreys Co.
Shelby Co.
Nashville
Polfc Co.
Beaumont-Port Arthur
Dallas-Fort Worth
El Paso -
Houston-Gal veslon-Brazon'a
Ogden
Salt Lake City
Tooele Co,
Utah Co.
Norfolk-yini. Beach-Newport (tows
Richmond . "
Stiiytti Co. (White Top Mta.)
Olympia-Tutnwaver-Lacey
- SeaWe-Tacoma
Spokane
Wallula
Yakjma
Door Co.
KcwsLinee Co,
Manltowoc Co.
MaraUionCo.
"Milwaukee-Racine
OneMaCo.
Stiotaytjan
Wahvorth Co.
Follansbee
New Manchester Gr, (In Hancock Co)
Wier.-BiJ tier-Clay (in Hancock Co)
Sheridan
POLLUTANTM
03 CO S02 PM10 Pb N02
1 .....
1 .....
1 .21 .
1 .....
1 .....
1 ...
1 .....
11 ....
1 .1 ...
1
1 .....
1 ...
1
1 ...
1 (1)
1 . . 1 (m) .
1 ...
1 .....
1 . . 1
-------
(d) Population figures were obtained from 1890 census data, For nonattainment areas defined as only partial
counties, population figures for just the nonattainment area were used when these were available. Otherwise,
whole county population figures were used. When a larger nonattainment area encompasses a smaller one,
double-counting the population is avoided by only counting the population of the larger nonattainment area. Note
that several smaller nonattainment areas may be Inside one larger nonattainment area, as is the case in Figure 1,
which is considered one nonattainment area. Caution must be used in these cases, as population figures will not be
representative of small nanattainment areas for-one pollutant inside larger nonattainment areas for another
pollutant. Occasionally, two nonattainment areas may only partially overlap, as in Figure 2. For the purpose of
this table, these are considered two distinct nonattainment areas,
(e) Carbon monoxide nonattainment area includes San Francisco county, and parts of Alameda, Contra Cosa, Mann,
Napa, San Mateo. Santa Clara. Solano, Sonoma counties.
(f) Lead nonattainment area Is a portion of Franklin township. Marion county, Indiana,
{g) Sulfur dioxide nonattainment area is a portion of Boyd county.
(h) PM-1Q nonattainment area is Granite City, Illinois, in Madison county,
(i) Lead nonattainment area is Herculaneum, Missouri in Jefferson county,
(I) Lead nonattainment area is a portion of Lewis and Clark county, Montana.
(k) Ozone nonattainment area is a portion of Dona Ana county, New Mexico.
(I) Lead nonattainment area is a portion of Shelby county, Tennessee.
(m) Lead nonattainment area is a portion of Williamson county, Tennessee.
(n) Lead nonattainment area is Frisco, Texas, in Collin county.
I i|j MA for O3
^NAforSOZ
NAfbrOS
NAforPM-10
rigure 1: (Multiple MA areas within a larger NA
jrea) 2 SO2 NA areas inside the Pittsburgh-
Jeaver Valley ozone NA Counted as 1 NA
area.
Rgure 2: (Overfappng NA areas) Searies
Valley PM-10 NA partially overlaps the San
Joaquin Valley ozone NA Counted as 2 NA
areas.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-15
-------
Table A-12. 1994 Metropolitan Statistical Area Air Quality Factbook Peak Statistics for Criteria Pollutants
METROPOLITAN STATISTICAL AREA
ABILENE, TX
A6UADILLA, PR
AKRON, OH
AL8ANY-SCHENECTADY-TROY, NY
ALBANY. GA
ALBUQUERQUE, NM
ALEXANDRIA, LA
ALLEffl-OWN-BETHLEHEM-EASTON. PA
ALTOONA. PA
AMAfULLO, TX
ANCHORAGE. AK
ANN ARBOR. Ml
ANNISTON. AL
APPLETON-OSHKOSH-NEENAH. Wl
ARECIBO. PR
ASHEWILL'E.NC
ATHENS, GA
ATLANTA, BA
ATLANTIC-CAPE MAY, NJ
AUGUSTA-AlKiN, GA'SC
AURORA-ELGIN, IL
AUSTIN-SAN MARCOS, TX
BAKERSFIELD, CA
BALTIMORE, MD
BANSOR, ME
BARNSTABLE-YARMOUTH, MA
BATON ROUGE,. LA.
BEAUMONTrPORT ARTHUR, TX
BELLINGHAM, WA
BENTON HARBOR, Ml
BERGEN-PASSAIC, NJ
BILLINGS, MT
BILOXI-GUUFPORT-PASCAGQULA, MS
BINGHAMTON, NY
BIRMINGHAM, AL
BISMARCK, :ND
BLOQMlNGTON-NORMAL, IL
BUOOMINQTON. IN
BOISE CITY, ID
BOSTON, MA-NH
BOULDER.LONGMONT, co
BRAZQRIA, TX
BREMERTON, WA
BRIDGEPORT, CT
BROCKTON. MA
BROWNSVILLE-HARLINGEN-SAN BENITO, TX
BRYAN-COLLEGE STATION, TX
BUFFALO-NIAGARA FALLS. NY
BURLINGTON, VT
CAGUAS. PR
See definitions and footnotes at end of lable
CO
1990 8-HR
POPULATION (PPM)
119,655
156,000
436,908
874,304
112,561
480,577
131,556
686.6BB
130,542
187,547
226,338
282,937
116,034
315,121
140,606
174,821
156,267
2,833,51 1
319.416
396,809
356,Bi4
781,572
543,477
2.382,172
88,745
94.132
628,254
361,226
127,780
161.378
1,278,440
113,419-
' 197,125
264,497
907.810
83,831
129,180
108,978
20S;775
2,870.669
225,339
391,707
189,731
443.722
189.478
260,120
121,862
1,189,288
131,439
173,961
NO
NO
7
S
NO
a
ND
8
2
ND
11
NO
ND
2
ND
ND
ND
5
5
ND
ND
6
6
7
ND
ND
5
2
NO
ND
7
6
ND
ND
7
ND
ND
ND
1 5
6
6
ND
ND
6
ND
4
ND
4
5
ND
PB
OMAX
fUGM)
ND
ND
O.OE
0.04
ND
ND
ND
0.13
ND
ND
ND
ND
ND
ND
ND
ND
ND
0.03
0.04
0.01
ND
ND
ND
0.04
ND
ND
0.10
0.04
"ND
ND
0.08
ND
ND
ND
0.11 (g)
ND
ND
ND
ND
0.01
ND
ND
ND
0.02
ND
ND
ND
0.05
ND
ND
NO2 OZONE PM10 PM10
AM 2ND MAX WTO AM 2ND MAX
(PPM) (PPM) (UGM) (UGM)
ND
ND
ND
IN
ND
0.023
ND
0.023
0.015
ND
ND
ND
ND
ND
ND
ND
ND
0.023
ND
ND
ND
0.018
0.020
0.032
ND
ND
0.018
0.012
ND
ND
0.031
ND
ND
ND
0.013
ND
ND
ND
ND
D.03B
ND
ND
ND
0.02S
ND
ND
ND
0.021
0,017
ND
ND
ND
0.10
0.12
ND
0.10
ND
0.12
0.11
ND
ND
0.09
ND
0.08
ND
0.08
ND
0.13
0.10'
0.10
ND
0.10
0.17
0.15
0.08
ND
0.14
0.12
0.08
0,12
0.11
ND
0.12
ND
0.11
ND
ND
ND
ND
0.12
0.09
0.11
ND
0.17
0.12
0.09
ND
0.10
ND
ND
ND
ND
28
25
ND
37
23
IN
26
18
IN
IN
IN
ND
ND
25
ND
32
"33
21
ND
20
40
33
22
ND
27
IN
IN
ND
41
IN
21
IN
34
18
ND
ND
39
29
21
ND
20
30
ND
26
ND
21
21
ND
ND
ND
80
67
ND
84
49
70
74
32
145
42
44
ND
ND
58
ND
71
56
45
ND
47
JM
75
59
NO
55
45
51
ND
101
62
40
44
104
40
ND
ND
110
SB
SB
ND
41
62
NO
53
ND
48
47.
NO
SO2
AM
{PPM!
ND
ND
0.012
0.007
ND
ND
ND
0.010
0.010
ND
ND
ND
ND
ND
ND
ND
ND
0.005
0.003
0.003
ND
ND
0.003
0.009
ND
ND
CkOOB
0.007
0.007
ND
0.008
0.019
0.003
ND
0.007
ND
ND
ND
ND
0.011
ND
ND
ND
0.010
ND
0.001
ND
0.012
0.003
ND
S02
24-HR
(PPM)
ND
ND
0,042
0.037
ND
ND
ND
0.053
0.058
ND
ND
ND
ND
ND
ND
ND
ND
0.023
0.019
0.014
ND
ND
0.007
0.031
ND
ND
0;02"5;
0:050
o.ois
ND
0.045
0.095
0.021
ND
0.037
ND
ND
ND
ND
0.041
ND
ND
ND
0.052
ND
0.004
NO
0.056
0.013
ND
A-16
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Table A-12, 1994 Metropolitan Statistical Area Air Quality Factbook Peak Statistics for Criteria Pollutants
METROPOLITAN STATISTICAL AREA
CANTON-MASSILLON. OH
CASPER, Wf
CEDAR RAPIDS, IA
CHAMPAIGN-URBANA, IL
CHARLESTON-NORTH CHARLESTON. SC
CHARLESTON, VW
CHARLOTTE-GASTONIA-RQCK HILL, NC-SC
CHARLOTTESV1LLE, VA
CHATTANOOGA, TN-GA
CHEYENNE, Wf
CHICAGO, IL
CHICO-PARAD1SE, CA
CINCINNATI, OH-KY-IN
CLARKSVILLE-HQPWNSVILLE, TN-Kr
CLEVELAND-LORAIN-ELYRIA. OH
COLORADO SPRINGS, CO
COLUMBIA, MO
COLUMBIA, SC
COLUMBUS, GA-AL
COLUMBUS, OH
CORPUS CHRISTI, IX
CUMBERLAND, MD-VW
DALLAS, TX
DANBURY. CT
DANVILLE. VA
DAVENPORT-MQLINE-ROCK ISLAND, IA-IL
DAYTONA BEACH, FL
DAYTON-SPRINGFIELD, OH
DECATUR, AL
OECATUR, IL
DENVER. CO
DES MOINES. IA
DETROIT, Ml
DOTHAN, AL
DOVER, DE
DUBUQUE, IA
DULUTH-SUPERIOR, MN-WI
DLTTCHESS COUNTY, NY
EAU CLAIRE, Wl
EL PASO, TX
ELKHART-GOSHEN, IN
ELMIRA, NY
ENID. OK
ERIE, PA
EUGENE-SPRINGFIELD, OR
EVANSVILLE-HENDERSON, IN-KY
FARGO-MOORHEAD, ND-MN
FAYETTEVILLE-SPRINCDALE-ROGERS. AR
FAYETTEVlLLE, NC
FITCHBURG-LEOMINSTER, MA
See cjsfinilions and toolnoles al end of table
CO
1990 8-HR
POPULATION (PPM)
394.106
61.Z26
168.767
173.025
506.875
250.454
1,162.093
131,107
433,210
73.142
6,069.974
182.120
1,452,645
169,439
2,202,069
397.014
112,379
453,331
243,072
1,377,419
349,894
101,643
2,553.362
187,8§7
108,711
350,861
370,712
951,270
131,555
11T.20B
1,622,980
392,928
4,382,299
130.964
110,993
86.403
239,971
640.220
137.543
591.610
156.198
95.195
56,735
275,572
282.912
278.990
153,298
1 13,409
274,566
102,797
5
NO
4
HO
4
4
6
NO
NO
ND
B
5
5
ND
a
5
ND
S
ND
5
ND
ND
5
ND
ND
ND
ND
4
ND
ND
8
5
10
ND
ND
ND
4
ND
ND
-8
ND
ND
ND
4
6
5
3
ND
6
ND
PB
QMAX
(UGM)
ND
ND
ND
ND
0.02
ND
0.03
ND
ND
ND
0.65 SB)
ND
0.04
ND
1.29 (c»
0,02
ND
0.02
1.43 <«
0.11
ND
ND
0.58 M
ND
ND
0.02
NO
0.04
ND
0.05
0.07
ND
0.07
ND
ND
ND
ND
ND
ND
0.14
ND
ND
ND
ND
0.02
ND
NO
ND
ND
ND
NO2 OZONE PM10 PM10
AM 2ND MAX WTDAM 2ND MAX
(PPM) (PPM) (UGM) (UGM)
ND
ND
ND
ND
0.011
IN
0.018
ND
ND
ND
0.034
0.015
0.027
IN
0.028
ND
ND
0.011
ND
IN
ND
ND
0.016
ND
ND
ND
ND
ND
ND
ND
0.035
ND
0.026
ND
ND
ND
. ND
ND
ND
0.034
ND
ND
ND
0.015
ND
0.016
ND
ND
ND
ND
0.10
ND
0.07
0.09
0.10
0.10
0.12
ND
0.12
NO
0.12
0.10
O.f3
ND
0.13
0.07
NO
0.10
0.11
0.11
0.11
ND
0.14
0.13
ND
O.OS :
0:09:
0.12
0,03;
0,10
0,11
0,07
0.14
ND
0.10
TO
ND
0.12
NO
0.14
0.10
0.08
ND
0.10
0.09
0.14
0.05
ND
0.10
ND
32
IN
24
25
26
ND
30
22
34
IN
44
33
32
22
80
29
ND
42
27
29
31
ND
29
IN
ND
60
26
27
IN
29
36
IN
49
28
ND
ND
21
ND
ND
39
ND
19
ND
IN
24
33
18 "
IN
IN
ND
61
46
47
SO
64
ND
SB
40
65
35
140
81
90
44
143
90
ND
116
49
78
57
ND
59
48
ND
147
63
61
45
66
107
92
129
S3
ND
ND
46
ND
ND
169
ND
.41
ND
54
143
102
39
49
44
ND
SO2
AM
(PPM)
0,009
ND
0.005
0.004
0.004
0.011
0.004
ND
ND
ND
0.009
ND
0.010
0.007
0.014
ND
ND
0.003
ND
0.006
0,002
0.010
IN
O.OOS
ND
. 0.bQ4%-
ND
0,007
IN
0.007
0,007
ND
0,010
ND
ND
IN
ND
ND
ND
0,008
ND
0.004
ND
0.010
ND
0.017
ND
NO
IN
NO
SO2
24-HR
(PPM)
O.OS2
ND
0,048
0.024
0,036
0.038
0.017
"ND
ND-
ND
0.060
ND
0,052
0.037
0.081
ND
. ND
0.01S
ND
0.041
0.013
0.037
0.018
0.037
ND
0;034r
ND
.ip:6i4 -
0;02i
0.030
0.034
ND '
0.045.
ND
ND
0.023 .
ND
ND
ND
0.031
ND
0,023
ND
0.07S
ND
0.061
ND
NO
0.011
ND
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-17
-------
Table A-12. 1994 Metropolitan Statistical Area Air Quality Factbook Peak Statistics for Criteria Pollutants
CO
1990 8-HR
METROPOLITAN STATISTICAL AREA POPULATION (PPM)
FLINT, Mi
FLORENCE, AL
FLORENCE, SC
FORTCOLLINS-LOVELANO, CO
FORT LAUDEROALE, FL
FORT MYERS-CAPE CORAL, FL
FORT PiERCE-PORT ST, LUCIE, FL
FORT SMITH, AR.QK
PORT WALTON BEACH, FL
FORTWAYNE. IN
FORT WORTH-ARLINGTON, TX
FRESNO, CA
GADSDEN, AL
GAINESVILLE, FL
GALVESTON-TEXAS CITY. TX
GARY, IN
GLENS FALLS,1 NY
GOLOSBORO, NC
GRAND FORKS,.NIMWN
GRAND RAPIDS^MUSKEGON+lQllAND, Ml
GREAT FALLS. MT
GRiELEY. CO
GREEN BAY, Wl
GREENSBQRQ-WINSTON-SALEM-HIGH POINT
GREENVILLE, NC
GRE6NV1LLE-SPARTANBUR6-ASDERSON, SC
HAGERSTOWN, MB '
HAMILTON'-MIDOLETOyVN, OH
HARRfSeUR&LEBANOti-CARLJSLE. PA
HARTFORD.CT
HICKORY-MORGANTON, NC
HONOLULU. HI
HOUMA, LA
HOUSTON, TX
HUNTINGTON-ASHLAND. VW-KY-OH
HUNTSViLLE, AL
INDIANAPOLIS, IN
IQWACITY.iA
JACKSON, Ml
JACKSON, MS
JACKSONVILLE. FL
JACKSONVILLE. NC
JACKSON, TW
JAMESTOWN, NY
JANESVILLE-BELQIT, Wl
JERSEY CITY, NJ
JOHNSON CITY-KINSSPORT-BRISTOL, TN-VA
JOHNSTOWN, PA
JOPLIN. MO
KALAMAZOO-BATTLE CREEK. Ml
See definitans and footnotes al end of table
430,459
131.327
114.344
186,136
1,255.486
335,113
251,071
175.911
143,776
383.811
1,332,053
667,490
99,840
204,111
217,399
604,526
118,539
78,143
70,683
B8B.399
77,691
131,821"
1i4,584
942, 091
88.741
640,861
121,393
2it,479
567,985
787,841
221,700
836,231
182,842
3,301,937
312,529
238,912
1,243,822
96,119
149.756
395.39S
906,727
149.B38
77,982
141,895
139.510
553,099
436,047
241,247
134,910
223,411
ND
ND
ND
6
6
ND
ND
NO
ND
5
4
9
ND
ND
ND
7
ND
ND
ND
4
5
5
ND
6
ND
6
ND-
ND
ND
8
ND
S
ND
6
5
4
4
ND
NO
5
5
ND
ND
ND
ND
11
3
4
ND
2
PB
UMAX
(UGM)
0.01
ND
0.01
ND
0.03
ND
ND
ND
ND
o.os
0.03
ND
0.06
ND
0.02
0.16
ND
ND
ND
0.02
ND
ND
ND
ND
NO
0.02
ND .
NO
0.04
0.02
ND
0.00
ND
0.01
0.04
ND
3.10
-------
Table A-12. 1994 Metropolitan Statistical Area Air Quality Factbook Peak Statistics for Criteria Pollutants
METROPOLITAN STATISTICAL AREA
KANKAKEE, IL
KANSAS CITY. MO-KS
KENOSHA.WI
KILLEEN-TEMPLE, TX
KNOXVILLE.TN
KOKOMO, IN
UCROSSE.WI-MN
LAFAYETTE, IN
LAFAYETTE, LA
LAKE CHARLES. LA
LAKELAND-WINTER HAVEN, FL
LANCASTER, PA
LANSING-EAST LANSING, Ml
LAREDO. TX
LAS CRUCES. MM
LAS VEGAS, NV-AZ
LAWRENCE. KS
LAWBENCE, MA-NH
lAWTQN, OK
LEWISTON-AUBURN, ME
LEXINGTON, KY
LIMA, OH
LINCOLN, NE
LITTLE ROCK-NORTH LITTLE ROCK, AR
LONGVIEWMARSHALL, TX
LOS'ANGELES-LONG BEACH. CA
LOUISVILLE, KY-IN
LOWELL, MA-NH
LUBBQCK, TX
LYNCHBURG.VA
MACON. GA
MADISON. Wl
MANCHESTER, NH
MANSFIELD, OH
MAYAGUEZ, PR
MCALLEN-EOlNBURS-MiSSION. TX
MEOFORD-ASHLAHD. OR
MELBOURNE-TITUSVILLE-PALM BAY. FL
MEMPHIS, TN-AR-MS
MERCEO, CA
MIAMI, FL
MIDDLESEX-SQMERSET-HUNTEROON, NJ
MILWAUKEE-WAUKESHA, Wl
MINNEAPOLIS-ST. PAUL, MN-Wl
MOBILE. AL
MODESTO. CA
MQNMOUTH-OCEAN, NJ
MONROE, LA
MONTGOMERY. AL
MUNCIE, LN
See delinrtions and footnotes al end of table
CO
1990 B-HR
POPULATION (PPM)
516.418
1,566.280
128.181
255,301
604,816
96.225
97.804
130,598
208,740
168.134
405,382
422,822
432,674
133,239
13S.S10
741.459
81,788
333.S16
111.486
88,141
348.428
154,340
213.641
513,117
163.431
3.863,164
. .. 9i2,6G2
273,067
222,635
142,139
281,103
367,085
147,809
, 126,137
133.497
383,545
146,389
398,878
961.747
178,403
3,132,582
1,019,835
1.432,149
2,464,124
476,923
370,522
386,327
142,191
292,517
119,559
NO
5
NO
ND
4
ND
ND
ND
ND
ND
ND
4
ND
ND
5
11
ND
ND
3
ND
4
ND
5
4
ND
15
B
7
ND
ND
ND
5
ND
NO
ND
ND
7
ND
e
NO
5
4
7
6
ND
6
5
ND
ND
ND
PB
QMAX
(UGM)
ND
0.03
ND
ND
ND
NO
ND
ND
ND
ND
ND
0.04
ND
NO
O.OE
ND
ND
0-00
ND
- NO
ND
ND
ND
ND
ND
a. OB
0,03
.ND
ND
ND
ND
NO
ND
ND
ND
ND
0.02
ND
2,20 (a)
NO
0,01
D.12
0.03
ND
ND
ND
ND
ND
ND
1.33
NO2 OZONE PM10 PM10
AM 2ND MAX WTDAM 2ND MAX
(PPM) (PPM) (UGM> IUGM)
ND
0.011
ND
ND
ND
ND
ND
ND
ND
0.006
ND
0.019
ND
ND
ND
0.027
ND
ND
0.008
ND
0.016
ND
ND
0.011
ND
0.050
0.026
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
0.'027
O.D13
0.014
ND
0,025
IN
ND
0.023
ND
ND
ND
ND
ND
0.11
0.12
ND
0.11
ND
ND
ND
0.10
0.11
0.09
0.11
0.09
ND
0,14
0,10
ND.
0.11
0.09
ND
0.11
0.10
0.08
0.10
0.10
0.24
0.13
ND
ND
ND
ND
O.OB
ND
ND
ND
ND
0.09
0.09
0.11
0.12
0.11
0.14
0.13
0.03
0.09
0112
0.12
D.10
0.10
ND
ND
40
ND
15
38
ND
NO
ND
21
23
ND
IN
ND
IN
40
47
ND
IN
IN
20
29
29
28
30
ND
47
35
ND
23
23
ND
22
ND
29
ND
ND
39
17
29
39
25
27
33
IN
31
41
ND
34
26
ND
ND
98
ND
35
69
ND
ND
ND
42
48
ND
117
ND
73
125
114
ND
35
51
46
80
48
49
62
ND
112
75
NO
153
40
NO
50
ND
SB
NO
ND
94
34
76
109
74
57
87
1S5
76
103
WD
99
72
ND
SO2
AM
(PPM)
ND
0.006
ND
ND
0.009
ND
ND
ND
ND
0,004
0.004
0.006
ND
ND
0.007
ND
ND
0.007
NO
0.006
O.OOB
0.004
NO
0.003
ND
0.004
0.013
ND
ND
ND
O.OD;
0.004
ND
ND
ND
ND.
ND
ND
0.005-
ND
0.001
0,005
0.004
0.002
0.011
ND
ND
0.004
ND
ND
SO2
24-HR
IPPM)
ND
0.034
ND
NO
0.057
ND.
ND
NO
ND
0.017
0.016
0.030
ND
ND
0,040
ND
ND
0.032
ND
0.02B
0.037
0.037
ND
0.009
ND
0.010
P.OSQ
ND
ND
ND
0.013
0.026
ND
ND
ND
. ND.
ND
ND
0.025
ND
0.004
0.028
0.032
0.036
0.052
ND
ND
0.009
ND
ND
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-19
-------
Table A-12. 1994 Metropolitan Statistical Area Air Quality Factbook Peak Statistics for Criteria Pollutants
METROPOUTAN STATISTICAL AREA
MYRTLE BEACH. SC
NAPLES, FL
NASHUA, NH
NASHVILLE, TN
NASSAU-SUFFOLK, NY
NEW BEDFORD, MA
NEWHAVEN-MERIDEN, CT
NEWLONDON-NORW1CH, CT-RI
NEW ORLEANS. LA
NEWYORK, NY
NEWARK, M
NEWBURGH, NY-PA
NORFOLK-VIRGINIA BEACH-NEWPORT NEWS
OAKLAND, CA
OCALA, FL
ODESSA-MIDLAND, TX
OKLAHOMA CITY. OK
QLYMPIA, WA
OMAHA, NE-tA
ORANGE COUNTY, CA
ORLANDO, FL
OWENSBORO, KY
PANAMA CITY, FL
PARKERSBURG-MAR1ETTA, WV-OH
PENSACOLA, FL
PEORlA-PEMN, 1L ' '
PHlLADRPHIA, WNJ
PHOENIX-MESA; AZ
PINE BLUFF, AR
PITTSBURGH. PA
PITTSFIELD, MA
PONCE, PR
PORTLAND-VANCOUVER, OR-WA
PORTLAND, ME
PORTSMOUTH-ROCHESTER, NH-ME
PROVIDENCE-FALL RIVER-WARWICK, RI-MA
PROVO-OREM, UT
PUEBLO, CO
PUNTAGQRDA.FL
RACINE, Wl
RALEIGH-DURHAM-CHAPEL HILL, NC
RAPID CITY, SD
READING, PA
REDOING, CA
RENO, NV
RICHLAND-KENNEVWCK-PASCO. WA
RICHMOND-PETERSBURG, VA
RIVERSIDE-SAN BERNARDINO, CA
ROANOK6.VA
ROCHESTER, MN
Sea definitions and footnotes al end of la&le
CO
1990 8-HR
POPULATION (PPM)
144,053
152,099
180,557
985,026
2,609,212
175,841
638,220
266,819
1,236,816
8,548,646
1,824,321
307,647
1,396,107
2,082,914
194,833
118,934
-- -958,139 :
. - 161,238
518,262..
2,410,556"
1,072,748
87,189
126,994
149,169
344.406
339.172
1 4;856sB8i'
2.122;l6l
85,487
' 2,Q58;705
79.250
253.285
1.239.842
215,281
223.578
i.i4i;sio
263,590 -
123;OS1
110,975
175,034
735,480
81,343
338.523
147,038
254,687
1 50.033
665,640
2,5B6,7.93
(224,477
106,470
'NO
ND
9
7
5
ND
8
ND
'5
7
11
ND
7
4
ND
ND
7
- 4
4
8
5
4
NO
ND
ND
6
: 6-
W
ND
7
ND
ND
8
ND
ND
7
9
ND
ND
4
7
ND
5
2
9
ND
4
s
6
S
PB
QMAX
(UGM)
ND
ND
0.01
1.38 fli)
ND
ND
0.17
ND
0.12
0.11
0.30
0.11
0.02
0.02
ND
-NO
0.01
ND
8.47 fl)
0.04
0.00
ND
ND
ND
ND
0.02
22,10 Q
0.04
NO
0.07
ND
ND
0.27
ND
0.02
ND .
ND
ND
ND
ND
ND
0.00
184(0
ND
ND
ND
ND
0.04
ND
ND
NO2 OZONE PM10 PM10
AM 2ND MAX WTDAM 2ND MAX
(PPM) (PPM) (UGM) (UGM)
ND
ND
0.015
0.020
0.028
ND
0.030
ND
0.020
0.048
0.042
ND
0.019
0.022
ND
ND
0.015
ND
ND
0.042
0.011
0.012
ND
ND
ND
ND
0,037
IN
NO
0,031
ND
ND
IN
0.002
0.013
0.022
0.024
ND
ND
NO
0.009
ND
0.023
ND
ND
ND
0.024
0.041
0.013
ND
ND
ND
0.11
0.12
0.13
o.io
MS
0.12
0.12
0.13
0,13
ND
0.10
0.13
ND
ND
0.10
ND
Q.OB '
0.21
0.11
0.11
ND
0.11
0.11
0.09
0.13
0.12
ND/
0:12
0.09
ND
0.11
0.12
0.12
0.12
0.09'
ND
ND "
0.11
0.11
ND
0.11
0:11
0.09
ND
0.12
0.23
0:10
ND
NO
ND
IS
36
24
19
28
23
31
53
43
ND
22
22
ND
ND
- - 23
IN
32
40'
26
26
23
ND
IN
26
111
-. 50
IN
41
ND
27
32
27
15-
37
33
IN
ND
ND
22
45
29
24
40
IN.
22
66
40
IN
NO
ND
40
71
65
49
106
S3
71
13D
107
ND
44
78
ND
ND
55
63
114
104
40
93
39
ND
33
82
371
114
56.
1ST
ND
64
70
69
37
70
122
54
ND
NO
38
144
80
54
140
103
40
fS4
83
43
SOI
AM
(PPM)
ND
ND
0.007
0.007
O.OOB
ND
0.010
o.a'as
0.008
0.0 18
0.009
NO
O.OOB
0.002
NO
ND
0.004
ND
0.003
0,002
0.002
O.OOS
ND
0.017
0.006
O.OOS
0.013
IN
ND
0,022
ND
ND
0.005
0.008
0.006
0.009
ND
ND
ND
ND
NO
ND
0,012
ND
ND
ND
O.OQ6
0.002
0.004
IN
S02
24-HR
(PPM)
ND
ND
0,037
0.071
0,039
ND
0.056
0,029
0.027
0.071
0.035
ND
0.025
0,009
ND
ND
0.007
.ND
0,018
0.008
0,012
0,035
ND
0.084
0.051
-0:063-.
0,057
0,003
ND
0.111 ft)
ND
ND
0.013
0.043
0.022
0.045
ND
ND
ND -
ND
ND
ND
0.044
NO
ND
ND
0.024
0.012
0.011
0.010
A-20
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Table A-12. 1994 Metropolitan Statistical Area Air Quality Factbook Peak Statistics for Criteria Pollutants
METROPOLITAN STATISTICAL AREA
ROCHESTER. NY
ROCKFORD. IL
ROCKY MOUNT. NC
SACRAMENTO, CA
SAGINAW-BAY CITY-MIDLAND, Ml
ST. CLOUD. MN
ST. JOSEPH, MO
ST. LOUIS, MO-IL
SALiM. OR
SALINAS, CA
SALT LAKE CITY-OGDEN. UT
SAN ANGiLO, TX
SAN ANTONIO. TX
SAN DIEGO, CA
SAN FRANCISCO, CA
SAN JOSE. CA
SAN JUAN-BAYAMON, PR
SAN LUIS OBISPO-ATASCADERO-PASO ROBLE
SANTA BARBARA-SANTA MARIA-LOMPOC, CA
SANTA CRUZ-WATSGNVILLE, CA
SANTA FE. NM
SANTA ROSA, CA
SARASOTA-BRAQENTQN, FL
SAVANNAH, SA
SCRANTON-VflLKES-iARRE-HAZiETON, PA
SEAmE-BELLEVUE-EVERETT, WA
SHARON, PA
SHEBQYGAN, Wl
SHERMAN-OEN1SQN, TX .
SHREVEPQRT-BOSSIER CfTY. LA
SIOUX CITY, IA-NE
SIOUX FALLS, SD
SOUTH BEND. IN
SPOKANE, WA
SPRINGFIELD, IL
SPRINGFIELD. MA
SPRINGFIELD. MO
STAMFORD-NORWALK, CT
STATE COLLEGE.'PA.
STEUBENVILIE-WEIRTQN, OH-VW
STOCKTON-LODI. CA
SUMTER, SC
SYRACUSE. NY
TACOMA, WA
TALLAHASSEE, FL
TAMPA-ST. PETERSBURG-CLEARWATER, FL
TiRRE HAUTE, IN
TEXARKANA. TX-TEXARKANA, AR
TOLEDO, OH
TOPEKA, KS
See definitions and footnotes at end of table
CO
1990 8-HR
POPULATION (PPMJ
1,002.410
2B3.719
133.235
1,481,102
399,320
190.921
83.083
2.444.099
278,024
355.660
1.072.227
98,485 .
1.302,099
2.49B.016
1,603,678
1.497,577
1,086,376
217,152
369.608
223,734
117.043
3BB.222
277,776
242.622
734,175
1,972,961
121,003
103.877
55,021
334,341
115.01B
123,809
247,052
361,384
189.SSO
S29.519
239,971
127,378
123.7B6
142,523
480,628
102.637
659,864
586,203
233,598
2,067,859
130,812
120,132
614,128
180,976
5
4
ND
8
ND
S
ND
6
8
2
8
NO
4
7
5
7
5
3
6
1
3
3
5
ND
4
7
ND
ND
ND
ND
ND
ND
4
9
3
8
6
6
ND
17
B
NO
7
6
NO
4
3
ND
4
ND
PB
QMAX
(UGM)
0.04
0.04
ND
0,02
ND
ND
ND
S.11 (m>
NO
NO
0.05
ND
0.03
0.02
0.02
0.02
' ND
ND
ND
ND
NO
0.01
ND
ND
ND
0.61
0.05
ND '
NO
ND
ND
ND
NO
ND
ND
0.01
ND
ND
ND
ND
0,00
0.02
ND
ND
ND
O.S9 H
ND
ND
0.70 (o)
0.01
NO2 OZONE PM10 PM10
AM 2ND MAX WTO AM 2ND MAX
(PPM] (PPM) (UGM) (UGM)
ND
ND
ND
0.022
ND
ND
ND
0.028
ND
0.012
0.02i
ND
ND
0.024
0.022
0,028
ND
0.014
0.022
O.QD6
0.003
0.015
ND
ND
O.OZO
ND
ND
ND
ND
ND
ND
ND
0,011
ND
ND
0.029
0.013
ND
ND
0.020
0.024
ND
NO
ND
ND
0.010
ND
ND
ND
ND
0.10
0,10
ND
0.14
ND
ND
' ND
0.1S
ND
0.09
0.11
ND
0.11
0.14
0,08
0.11
ND
0.10
0.13
0,09
0.07
0.09
0.10
ND
0.11
0,13
0.11
QM
ND
0.09
ND
ND
0.11
0.09
0.10
0.13
0.10
0.16
NO
0.11
0.12
ND
0.11
0.11
ND
0.10
0.11
ND
0.12
ND
22
19
21
28
22
ND
34
AS
ND
20
38
ND
25
51
IN,
2S
34
22
33
31
1S
IN
26
ND
26
2B
30
ND
ND -
26
23
24
19
34
' 22
24'
18
36
ND
39
37
ND
25
27
ND
30
28
23
28
IN
45
44
41
101
45
ND
77
122
ND
33
140 -
ND
53
121
72
89
82
4S
56
61
29
51
81
ND
63
83
6B
NO
ND
51
69
45
71
115
53
08
39 -
7B '
ND
187 DO
93
ND
64
76
NO
69
S7
52
66
49
SO2
AM
(PPMJ
0.013
ND
ND
0.001
ND
NO
IN
0.014
ND
ND
0.011
ND
ND
0.003
0.001
ND
0.013
ND
0.002
O.Q02
0.002
ND
0.003
0.003
0.007
.0,007 '
0.006
ND
ND
0.002
ND
ND
ND
ND
0.006
0,008.
0.010
0.010
ND
0.035
ND
ND
0.004
0.007
ND
0.007
0.012
ND
0.007
ND
SO2
24-HR
(PPM)
0,052
ND
ND
0,007
ND
ND
0.062
0.089
ND .
ND
0,039
ND
ND
0.015
0.005
ND
0.077 - .
ND
0.005
0.006
O.OOB
ND
0.017
0.015
0.036
0.026
0.047 -
ND
ND
0.003
ND
ND
ND
ND
0.050
0.070
0.103
0:057
ND
0.200 [k)
ND
ND
0.022
0.024
ND
0.095
0.044
ND
0.056 -
ND
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-21
-------
Table A-12. 1994 Metropolitan Statistical Area Air Quality Factbook Peak Statistics for Criteria Pollutants
CO
1990 8-HR
METROPOLITAN STATISTICAL AREA POPULATION (PPMJ
TRENTON. NJ
TULSA, OK
TUSCALOOSA. AU
TUSCON. AZ
TYLER, TX
UTICA-ROME, NY
VALLEJO-FAIRFIELD-NAPA, CA
VENTURA. CA
VICTORIA; TX
VINELAND-MILLVILUE-ORIOGErON, NJ
VISAUA-TULARE.PORTERV1I.LE, CA
WACO. TX
WASHINGTON. DC-MD-VA-VW
WATERBURY, CT
WATERLOO-CEDAR FALLS. IA
WAUSAU, Wl
WEST PALM BEACH-BOCA RATON. FL
WHEEUNG.WV-OH
WICHITA FALLS, TX
WICHITA, KS
WILLIAMSPORT. PA
WILMINGTON-NEWARK, DE-MO
WILMINGTON, NC
VTORCESTER. MA-CT
YAKIMA, WA
YOLO, CA
YORK, PA
YOUNGSTOWN-WARREN, OH
YUBA CITY, CA
YUMA.AZ
CO = Highest second
325,824 ND
70B.9S4 5
150,522 ND
666.BBO 6
151,309 ND
316,633 ND
451,186 i
669.016 4
74,361 ND
13B.OS3 ND
311.921 4
189,731 ND
3,000,504 6
221.629 ND
146.611 ND
115,400 ND
863,518 3
159,301 5-
122,378 ND
485,270 7
118,710 ND
578.BB7 4
120,284 ND
320,006 6
188,823 8
381,288 5
417J84B . 4
492,619 3
-- 122,643 "6
108,895 ND
PB N02 OZONE PM10
QMAX AM 2ND MAX 'WTDAM
(UGM) (PPM) (PPM) (UGM)
ND ND
0.10 0,017
NO ND
0.05 0.021
ND ND
ND ND
0.01 0.01i
ND 0,024
ND ND
ND ND
ND 0.023
ND ND
0.04 0.030
0.02 ND
ND ND
ND ND
0.00 0.012
ND ND
ND ND
0.01 ND
ND ND
ND 0.019
ND ND
ND 0.025
ND ND
. ND NO
ojJ4 0:024
ND 0.017
ND 0.016
ND ND
0.14
0,13
ND
0.10
0.10
0.09
0.10
O.f8
0,09
0,10
0.1S
ND
0,13
ND
ND
0.08
0.09
0.10
ND
0.09
O.OB
0.13
0.10
0.13
ND
0.10
0,12 '-.
0.10
an
ND
29
28
26
31
18
21
21
31
ND
ND
48
ND
29
27
29
ND
20
31
IN
32
27
38
IN
' 20
31
30
31
39
34
34
PM10
2ND MAX
(UGM)
64
S3
4B
63
40
49
57
67
ND
ND
93
ND
84
58
59
ND
56
69
73
100
61
82
30
44
ae
.71
80
- 110
81
54
SO2
AM
(PPM)
ND
0,005
ND
0,002
ND
0.002
0.002
0.001
ND
0,005
ND
ND
0.011
0.006
ND
0.004
0.002
0.019
ND
0.004
0.006
0,014
ND
0.008
ND
NO
"0.009
0.013
ND
NO
SO2
24-HR
(PPM)
ND
0.036
ND
0.004
NO
0.011
0.007
0.004
ND
0.032
ND
ND
0.038
0.030
ND
0.024
0.016
0.087
ND
0.005
0.042
0.056
ND
0.024
ND
ND.
0.041
0.084
- ND
ND
maximum non-overlapping 8-hour concentration (Applicable NAAQS is 9 ppm}
PB - Highest quarterly maximum concentration (Applicable NAAQS is 1.5 uo/m3)
NO2 = Highest arithmetic mean concentration (Applicable NAAQS is 0.053 ppm)
O3 = Highest second
daily maximum 1-hour concentration (Applicable NAAQS is 0.12 pprn)
PM10 = Highest weighted annual mean concentration (Applicable NAAQS is 50 urj/m3)
Data from exceptional events not included
= Highest second
maximum 24-hour concentration (Applicable NAAQS is 150 ug/m3)
S02 ~ Highest annual mean concentration (Applicable NAAQS i
- Highest second
i 0,03 ppm)
maximum 24-hour concentration (Applicable NAAQS is 0.14 pprn)
ND Indicates data not available
IN ' - Indicates insufficient data to calculate summary statistic
WTO
AM
UGM
PPM
= Weighted
= annual mean
= Units are mierograms per cubic meler
= Units are parts pef million
(a) - Impact from an industrial source in Leeds. AL Highest population oriented site in Birmingham, AL is 0.11 ugta3.
(b) - Impact from an industrial source in Chicago, It. Highest population oriented site in Chicago, IL is 0.10 ug/m3,
(c) - Impact from an industrial source in Cleveland. OH. This facility has been shutdown. Highest sits in Cleveland. OH is 0.12 ug/rn3.
(d) - Impact from an indusuial source in Columbus. CA Highasl population oriented sita in Columbus, GA is 0.16 ug/m3.
(e) - Impact from an industrial source in Collin Co., TX. Highasl population oreinM site in Dallas, TX is O.OB uglm3.
(I) - Impact torn an industrial source in Indianapolis, IN. Highest population oriented site in Indianapolis, IN is 0.2 ug/m3
(g) ~ Impact from an industrial source in Memphis, TR Highest population oriented site in Memphis, TN isO.IQugfrnS.
(h) - Impact from an industrial source in Wliarnston Co., TN. Highest population oriented silo in Nashville, TN is 0.09 ug/m3_
(i) - Impact from an industrial source in Omaha, NE. Highest population oriented site in Omaha, NE is 0.67 ug/ni3
0) - Impact from an industrial source in Philadelphia. PA. Highest population onented site in Philadelphia. PA is O.Wug/mS,
(k) - Impact from an induslrial source.
(I) - Impact rrarn an induslrial source in Reading. PA.
(m) - Impact from an industrial source in Herculaneurn, MO. Highest population oriented site in St. Louis is 0,06 ug\m3-
(n) - Impact from an industrial source in Tarnpa. FL.
(a) - Impact from an industrial source in Toledo, OH.
A-22
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Table A-13 Number of PSI Days Greater Than 100 at Trend Sites, 1985-94, and All Sites in 1994
METROPOLITAN STATISTICAL AREA
AlBANY-SCHENECTADY-TROY, NY
ALLENTOWN-BETHLEHEM-EASTON, PA
ATLANTA, GA
AUSTIN-SAN MARCOS, TX
BAKERSFIELO, Cft
BALTIMORE, MO
BATON ROUGE, LA
BERGEN-PASSAJC, NJ
BIRMINGHAM, AL
BOSTON, MA-NH
BUFFALO-NIAGARA FALLS, NY
CHARLESTON-NORTH CHARLESTON, SC
CHARLOTTE-GASTONIA-ROCK HILL, NC-SC
CHICAGO. IL
CINCINNATI, OH-KY-IN
CLEVELAND-LORAIN-ELYRIA, OH
COLUMBUS, OH
DALLAS. TX
DAYTQN-SPRIIilGFIELD, OH
DENVER, CO
DETROIT, Ml
EL PASO, TX
FORT LAUOEROALE. FL
FORT WORTH-ARLINGTON, TX
FRESNO, CA
GAR*, IN-- .- . ;':- .-..".
GRAND.RAPIDS-MUSKEGON-HOU-AND..MI .' :
GREErtSBORO-WINSTON-SAiEM-HIGH POINT
GREENVILLe^PARTANBliaS;:ANWHSON,--SCy
HARRISHtlRB-LESANONiCAfiLiSLfepA :
HARTFORD. CT
HONOLULU. HI
HOUSTON. TX
INDIANAPOLIS; IN
JACKSONVILLE, FL
JERSEY GITY, NJ
KANSAS CITY, MO-KS
KNOXV1LLE, TN .
tAS VEGAS, fJVAZ
LfTTLi ROCK-NORTH.LrTTiE ROCK, AS
LOS ANGELES-LONG BEACH, CA
LOUISVILLE, KY-IN
MEMPHIS. TN-AR-MS
MIAMI. FL
MIDDLESEX-SOMERSET-HUNTERDON, NJ
MILVVAUKEE-WAUKESHA, Wl
MINNEAPOLIS-ST. PAUL, MN-W1
MONMOUTH-OCEAN, NJ
NASHVILLE, TN
NASSAU-SUFFOLK, NY
tK trend
sites
4
9
7
4
7
15
6
8
17
24
20
7
7
40
19
25
9
9
;11
20
25
16
5
3
5
: MT
"' --:6"
-'-7
' - \
--S
14
4
28
24
13
a
19
10
8
6
37
1S
10
7
f
17
14
*
4
11
i
985 1986 1987 1988 1989 1990 1991 1992 1993 1994
2003000001
435 16 003001
9 18 27 21 3 17 6 5 17 4
3002101001
57 54 70 85 56 48 48 16 49 45
25 23 28 43 9 12 20 5 14 17
10 6 10 10 8 18 6 2 3 2
8 5 14 19 4 43 0 0 0
3 7 11 16 3 5 0 2 5 0
32 5 15 4 13 1 3 1
214 19 120000
0200000000
6 12 10 21 352040
99 17 22 4387 18
57 11 24 367015
1 2 7 21 6 2 7 1 2 4
0 11 40 1 3 10 6
27 9 13 14 7 8 135 1.
0 2 3 17 3 1 1 03 2
38 49 37 19 11 9 7 73. 2
259 17 10 38028
32 43 32 16 33 27 10 13 6 10
0000100000
12 10 4 11 8 5 9 2 1 8
37 37 49 29 45 22 32 27 27 11
-, .-10-;. :8 8 - 13 ': . 1 -:?... . '-.'$.-. ;. '-;. ("& : _ , 0" :.;-.1-
'\ -2 2 5- 16 '.. \3-: ' '?;- 2 ';'-!"&:---. 1 '-'."l
0 3 1 12 :Q 1 0 0 2 : 0
-o o o : 4 o o o rfli? 1 a
:- --2 0 5:- 13 '* Q, """ 2 '"'""- 0 '"6": V" 2"
17 7 20 27 11 7 14 Q 9 10
0000000000
64 55 67 61 42 61 42 31 26 29
2039210102
2022010010
26 8 12 18 2 7 8 1 5 1
34 6 4 221 12 0
0 0 0 80 5 0020
:56 40 7 30 46 21 15 58 -12
p i i : o : o 1 o o o o
206 226 201 239 226 178 182 185 146 136
492 20 344064
15 13 10 8 4 6 1 1 40
5.44541 2000
17 7 10 24 8 12 8 3 1 5
5 10 13 19 8 2 10 0 0 4
22 13 7 1 5 1 0 1 0 3
2000000000
394 17 481 1 33
4 9 15 10 6 7 13 2 4 3
Total #
sites
14
11
13
S
27
28
13
?
17
29
22
10
26
58
24
40.
13
"w:-?3
, 12
35
35
19
20
8
16
' -26
10
.:.-^
...'''::8
- ' "7
17
13
30
33
19
9
25
17
1t
8
41
27
16
12
7
22
25
4
27
- 7
PSI >100
1994
1
1
4
1
50
18
-.4'
o;
0
2
0
0
1
8
5
-7"
':" -'1
;' ": ;7
::2.
' :2r
8
10
0
8
19
;; -A2
'-. 3
: :""j
;.- ;--.o;
i;:. ' >
10
0
32
2
0
7
0
1
V:".: 12-
0
136
5
2
0
e
K
*3
0
2
%.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-23
-------
Table A-13 Number of PSI Days Greater Than 100 at Trend Sites, 1985-94, and All Sites in 1994
METROPOLITAN STATISTICAL AREA
NEW HAVEN-MERIDEN, CT
NEW ORLEANS, LA
NEW YORK, NY
NEWARK, NJ
NORFOLK-VIRGINIA BEACH-NEWPORT NEWS
OAKLAND, CA
OKLAHOMA CITY, OK
OMAHA, NE-LA
ORANGE COUNTY, CA
ORLANDO. FL
PHILADELPHIA, PA-NJ
PHOENIX-MESA, AZ
PITTSBURGH PA
PORTLAND-VANCOUVER, OR-WA
PROVIDENCE-FALL RIVER-WARWICK, RI-MA
fSALEIGH-DURHAM-CHAPEL HILL, NC
RICHMOND-PETERSBURG, VA
RtVERSIDE-SAN BERNARDINO, CA
ROCHESTER, NY '
SACRAMENTO, CA
ST. LOUIS, MO-IL
SALT LAKE CITY-OGDEN. UT
SAN ANTONIO, TX
SAN DIEGO, CA
SAN FRANCISCO, CA
SAM-JOSE, CA: ; ; .:". .. - ;-"- - '.
SANfJUAli-BAYAMflN, PR\ '..-.""''
SCRAtilfQN-WlLlCESaARRE-HAZLEtQN.'PA
SEAmE-BELLfeyU'E;.EVERETT,WA .'.
SPR{MFiELD;.&tA*.
SYRACUSE, NY
TACOMA, WA
TAMPA-ST. PETERSBURG-CLEARWATER, FL
TOLEDO, OH
TUSCON, AZ
TULSA, OK ' " -
VEimiRACA' : '
WASHINGTON, DC*1D-VA-Wtf:
WES^PAUid^ BeACH-BOCA:RATON,'FL
WILMIMSTON-llEWARK, BE-MD
« trend
sites
12
8
24
13
B
22
11
9
10
S
36
22
31
11
13
3
9
34
8
18
46
19
7
21
11
\9
" ' 6'
11
13
- is
4
8
20
6
16
10
14
32
2
8
198S 1986 1887 1988 1889 1980 1991 1992 18S3 1994
11 7 17 16 7 10 22 3 11 8
1352100122
65 58 44 46 18 18 22 4 6 8
24 20 24 33 5 8 11 5 2 6
1158001242
12 ' 8 14 10 3 5 6 2 3 3
6460220002
31"01 100011
78 66 58 65 66 47 42 43 25 14
0 1 0 0 0 200 0 0
31 23 36 35 20 14 25 3 22 6
88 88 42 26 30 9 4 9 7 7
9 8 13 25 9 11 4 2 5 2
36 11 8689202
12 7 10 9 2 7 11 2 1 2
002 12 000000
"5 18 18 111241
168 170 171 180 177 143 141 160 139 122
0115010000
75 69 52 76 60 43 44 21 10 11
10 13 17 18 13 8 6 3 5 11
21 36 8 11 17 6 19 10 3 10
3222010001
88 70 61 84 90 60 39 37 17 16
5412110000
;< 34 17 18 . 16 21 11 11 220
0 0 200 0 0 0 0 0
1 0 1 12 10 2 0 0 0
:'25 13 14 20 85 2 .1 0 0
12 5 3 19 5 4 54 73
19 942212000
12 4 9 9 4 3 1 1 0 1
6551130100
0 2 2 6 1 01 03 1
3246200000
5422232112
31 : 84 S4 83 59 38 49 " 25 16 24
17 12 26 37 8 S 17 2 13 .7
0 00 0 0 00 0 0 0
10 9 16 31 7 5 6 2 3 1
Tofalff
sites
13
14
34
17
14
29
14
13
12
16
52
28
50
17
21
18
11
58
9
39
61
31
7
27
11
14
19
- 11
21
17
9
9
33
8
29
13
16
55
9
12
PSf>10Q
1994
a
2
9
6
2
3
2
1
14
0
18
9
a
4
3
1
1
124
0
13
13
11
1
16
0
1
'. .:. 0
0
4
3
0
1
0
2
0
2
24
8
0
7*
A-24
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Table A-14 (Ozone Only) Number of PSI Days Greater Than 100 at Trend Sites, 1985-94. and All Sites in 1994
METROPOLITAN STATISTICAL AREA
ALBANY-SeHENECTADY-TRQY. NY
AUENTQWN-BETHLEHEM-EASTON, PA
ATLANTA, GA
AUSTIN-SAN MARCOS, TX
BAKERSRELD, CA
BALTIMORE, MD
BATON ROUGE, LA
BERGEN-PASSAJC, NJ
BIRMINGHAM, AL
BOSTON, MA-NH
BUFFALO-NIAGARA FALLS. NY
CHARLESTON-NORTH CHARLESTON, SC
GHARLOTTE-GASTQNIA.ROCK HILL, NC-SC
CHICAGO, IL
CINCINNATI, OH-KY-IN
CLEVELAND-LORAIN-ELYRIA, OH
COLUMBUS, OH
DALLAS, TX - . . .
DAYTON-SPRINGFIELD, QH :
DENvea'co
DETROIT, Ml
EL PASO, TX
FORT LAUDERDALi, FL
FORT WORTH JWL1NGTON, TX
FRESNO, CA
6ARY.1N . '.. . ' V " '/ :"
GRAND RAPIDS-MUSKESON-HOLLAMD, Ml !. , j
GREENSBORO-VVINSTON^A^rHieH'pilMt^
GRE6(«ltli^PAWAlMBDRS^biRSON,.:Sev:-
HARRiSBURCMBBANOH-CARtlSLlrPA .' "!
HARTFORD, CT
HONOLULU, HI
HOUSTON, TX
INDIANAPOLIS, IN
JACKSONVILLE, FL
JERSEY crrrviu ..-. "
KANSAS CtTYiMO-KS. : . /, : . ..
KNGXVKIEITN. - . ; ,;
LAS'VE!3AS.NV-AZ . - .'".;:
LrrTLE:ROCK-NORTH LfTTLE RQCICAR '
LOS ANGELES-LONS BEACH. CA
LOUISVILLE, KY-IN
MEMPHIS, TN-AR-MS
MIAMI, FL
MIDDLESEX-SOMERSET-HUNTEROON. NJ
INLWAUKE64MMIKESHA..WI
MINNEAPOLIS^ PAUL. MN-VW
MONMOUTH-OCEAN.-NJ
NASHVILLE, TN
NASSAU-SUFFOLK, NY
tf trend
sites
2
3
3
2
3
6
3
1
S
3
2
2
3
15
7
7
- "i
-- i-3
3
5
7
3
1
2
3
- ' -:,--4
:''' 12
':#
': '.,1
' ' 'V3
3
1
11
5
2
1
- .,5
2.
- : .2
_ \2
14
4
3
3
2
6
3
0
3
1
1985 1986 1987 1988 1989 1890 1991 1892 1993 1994
2003000001
435 15 003000
9 18 27 21 3 17 6 5 17 4
3002101001
55 51 69 80 50 41 41 15 49 43
15 18 26 40 8 11 20 , ,5 14 16
10 6 10 10 9 18 6 2 3 2
8 2 13 18 2 3 3 00 0
35 7 15 1 S 025 0
3 2 4 15 4 1 3 1 31
2 04 18 1-1 0000
0200000000
1 10 10 21 2 3 2 0 4 0
96 16 21 307302
37 11 24 367015
1 2 7 21 . 3. 2 7 1 1 2
: 0 1 1 4 0 1 3 0 0 0
;'': 25 9 13'.l4-:- . 7 .;.'.--«; i- :' "3 -'"".5--:- -"!
022 17: 3 1 1 0^3 2
13 5 4-."" 0 2 B; 0 0 0
1 3 6 16 10 38 0 26
18 19 17 6 13 9 7 7 4 6
0000100000
12 10 4 11' 8 5 9 2 1 8
37 37 49 28 45 22 32 27 27 11
'- -.2 -:.&<- 6 134:;.. o :'.' 'a.-- ,3-. :.-;2-v;.o 1
:. -2 . "2; 5 JiT-' ..3 ,-- 2 .'.'-'i' -:.;;0,:'-: i; '- 1
- , "o..-,: -.'3-.. . i '; .12'-.. ,. .a ' 1- ".o.V;O:o. ."'j:. '.=.': ;o
:;,'^;-::-;':;;o-;.:-v:p--;:--^4:\:- -:ov -'"a" ;'^:;v;^6/:- "1* '::':t
"' ':i-.. ./6.;.-:5'--- i3.-".--Vb'-. . 2-" :3;o:^-: ::b: r '::2
11 2 10 24 9 7 12 8 9 10
0000000000
64 53 66 61 42 61 42 31 26 29
2039210002
2022000010
15 4 12 18 2 .7 8 t 5 1
3 3 ..S 4 1 2 1 1 1 0
o ^b o 8 q 5 o o: 2 o
i . o o 2 i o o a o o
o 1 i a p 1 o D o o
16B 174 160 178 154 132 134 143 116 107
492 20 144064
8658240010
3445312000
17 7 10 24 8 12 8 3 1 5
5 10 13 19 8 2 10 0 0 4
0 1 1 1 0 00 0 0 0
0 0 0 0 0.00 002
3 3 3 17 2 7 1 123
48 11 867 13 243
Wai*
sites
3
3
4
2
9
8
7
1
6
6
2
3
6
22
8
:.'' ' S
'-.. -4:
.'-" -:-6:
.":*
9
8
4
3
2
6
4
-'- !-:5
. : ' 6
v' : 'I
..' ':3
3
1
11
7
3
1
6
: ' - 7
-....-;4
-iJV;-2
15
6
4
4
2
9
5
0
8
L 2
PSI >100
1994
1
0
4
1
48
17
- '4
0
0
2
0
0
1
2
5
- " .- 3
:-.:=-O
-:'." -7
. '2
6
6
6
0
8
19
- " -1
: . .3
'.'.. ? :1
/^T^o
: ' -:->2
10
0
32
2
0
: -' ' 't
:=-.,. -:0
L-...r..-.t
::':;:r:':6
C-;:: :-:"0
107
- 4
1
0
5
5
0
0
3
3
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-25
-------
Table A-14 (Ozone Only) Number of PS! Days Greater Than 100 at Trend Sites, 1985-94. and All Sites in 1994
METROPOLITAN STATISTICAL AREA
NEWHAVEN-MERIDEN, CT
NEW ORLEANS, LA
NHWYORK, NY
NEWARK, NJ
NORFOLK-VIRGINIA BEACH-NEWPORT NEWS
OAKLAND, CA- -
OKLAHOMA CITY, OK
OMAHA, NE-1A
ORANGE COUNTY, CA
ORLANDO, FL
PHILADELPHIA, PA-NJ
PHOENIX-MESA, AZ
PITTSBURGH. PA
PORTLAND-VANCOUVER, OR-WA
PROVIDENCE-FALL RWER-WAHVMCK, RI-MA
RALEIGHDURHAM'-CHAPEL HILL, NC
RICHMOND-PETERgBURS.VA '
RiVERSIDE-SAN BERNARDINO, CA-
RpCHESTER, NY
SACRAMENTO, CA : '
ST. LOUIS, MO-1L
SALT LAKE CITY-OGOEN, UT
SAN ANTONIO, TX
SAN DIEGO, CA
SAN FRANCISCO, CA
SAXTOSEi-m /:;. .. ' _,"';.'.. ;,.. ';-
SftN-aUAN^fiAYAMQf4,.PR' ' ' . ' ' , - ' ' V /
SCRANtON-WlLKESiBAftRfe-HAZLETdM, PA = '
SEAmBBELLEVUE-E^RETt^WA '.- ;"
SRRINGFIELtKMA':- .-- ' ' ' " . .-
SYRACySE, NY
TACOMA, WA
TAMPA-ST. PETERSBURG-CLEARWATER, FL
TOLEDO, OH
TUSCON, AZ
Tlit,SA,"0'K ':
VINTURA;eA;. . . .' '
WASHINGTON; OC-ltoi-VA-WV. '
WEST. PALM BEACH-BOCA RATON, FL ' '.
vifiLMIN6TON^NBVARK;'cJE«
8 trend
sites
2
4
5
3
2
7
3
3
4
2
9
8
6
3
2
1
3
1'5
2
7
14
4
2
7
3
--4
v - :l
. - "'4
i
3
1
1
5
2
4
rj
.6
13
1
'2
1985 1886 1987 1988 1989 1990 1991 1992 1993 19S4
11 7 17 16 7 8 20 3 7 6
1252100122
20 8 18 32 12 13 19 3 6 8
10 12 23 30 4 7 8 5 2 4
1137001242
12 8 14 10 3 5 5 2 3 3
1010020000
0000000000
70 63 54 55 48 44 42 41 25 14
0100020000
31 21 35 35 18 14 25 3 22 5
9023030452
2 15 16 202032
2422041 200
96 10 827 11 21 2
0 0 2 12 00 0 0 0 0
51 7 18 1 1 12 4 1
157 165 168 179 168 136 138 148 138 121
01 1 50 1 0 0 0 0
25 31" 30 52 20 18 2i 20 8 11
10 11 14 18 7 8 6 3 5 10
14 928721001
3122010001
85 67 60 80 81 60 39 37 17 16
1010000000
;-..10>.-'.:3"."-"lfr.--- 1t'.-..-B * 2\ ;$> >£, ".2,- _-Q
'0 -: ;o. D o b o o o 0:6
.':-,.!. --"0.;.. ;i ~.'iz.- i. - .'o. "'.?':.' ;b\.v-::6' :.'-; D
: ,',' i :'i::'.'. 'O;-.' V'-'-'o " ^2: "o; 0 0\ 0
."" 12"' ::3"" -2- 19- . 5.--- -4' :-S- ' 3 . ' 7 ,3
0011000000
0000020001
6550130100
0226101031
0000000000
5 4: 1 2 23 2 0 ;1 2
'-3"1.- 83 54- ,83 '59- 36 - .49 25 ' 16 24
: ; "14V" -' id .. 21::' 35. :5 - ' '5: 16 2 '13 "-'"7
0 0 0 0 00 0 0 0^ 0
: 10 9 16 31 7 5 6 2 3 i
Total #
sites
2
6
7
3
3
9
4
3
4
4
11
9
9
4
3
5
4
21
- 2
13
17
8
2
9
3
7
0
v V4
-: -a
-4
2
1
7
4
7
3
'"7
18
2
4
PSI >100
1994
6
2
9
4
2
3
0
0
14
0
5
4
4
1
3
1
1
123
0
13
11
1
1
16
0
1
0
0
; ''2
3
0
1
0
2
0
.2
24
8
0
7.
A-2o
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Table A-15. Total Number of PSI Days Greater Than 100 at Trend Sites, 1985-94, and All Sites in1994
METROPOLITAN STATISTICAL AREA
(rend 1985 19B6 1987 1988 1989 1990 1991 1992 1993 1994
sites
Tola!*
sites
PSI >100
1994
ALL POLLUTANTS
AIL TREND SITES
LOS ANGELES-LONG 8EACH, CA
RIVERSIDE-SAN BERNARDINO. CA
ALL EXCEPT LA AND RIVERSIDE
1204
37
33
1134
1656 1567 1538 1954 1250 1008 994 678 676 613
208 226 201 239 226 178 182 185 146 136
168 170 171 180 177 143 141 150 139 122
1280 1171 1166 1535 847 687 671 343 391 355
1833
41
56
1736
704
136
124
444
OZONE ONLY
ALL TREND SITES
LOS ANGELES-LONG BEACH. CA
RIVERSIDE-SAN BERNARDINO. CA
ALL EXCEPT LA AND RIVERSIDI
352
14
15
323
1108 1057 1226 1675 889 818 839 578 615 530
168 174 160 178 154 132 134 143 116 107
157 165 168 179 168 136 138 148 138 121
783 716 898 1318 567 550 567 287 361 302
502
15
21
466
589
107
123
359
NATIONAL Am QUALITY AND EMISSIONS TRENDS REPORT, 1994
A-27
-------
Table A-16. Emission Reductions for Regulations Promulgated in 1990-95
SOURCE CATEGORY
Promul.
Chromium Electroplating
Coke Ovens
Commercial Sterilizers
Degreasers
Industrial Cooling Towers
Magnetic Tape
Stage 1 Gasoline Marketing
Perchloroethylene Dry
Cleaning
Hazardous Organic
NESHAP (HON)
Aerospace Industry
Marine Tank Vessels
Petroleum Refineries
Municipal Waste
Combustors 1 & II
Polymers & Resins II
Secondary Lead Smelters
11/94
10/93
11/94
11/94
7/94
11/94
11/94
9/93
2/94
9/95
9/95
8/95
9/94,
10/95
2/95
5-93
Dates
Compliance
11/97
12/97
12/97
1/95
11/96
11/97
12/95-12/97
9/96
4/97
9/98
9/98
9/99
8/98
New-at Startup
Exist- 3-5 yrs
3/98
6/98
No. of
Facil.
Emiss. Reduc.,
Mg/Yr
5,000
75 Batt.
75
25,000
14
260
30,000
370
3,000
28
190
200
19
23
173
1,305 if MACT
1,500 if LAER
1,000
77,000
25
2.080
2,300
35,600
460,000
164,100
4,500
48,000
181
97
1,300
HAPs Controlled
Pollutants
Chromium
Coke Oven Emissions
Ethyiene Oxide
Methylene Chloride, TCE,
Perchloroethylene, 11 1-TCA.
Carbon Tetrachloride.Chloroform
Chromium
MEK, MIBK, Toluene, Xylene, Elhylbenzene
Hexane, Toluene, Benzene, Others
Perchloroethylene
Many CAAA Section 112 HAPs
Chromium, Toluene, MEK, TCE, 1 1 1-TCA
MIBK, Many others
Benzene, Hexane, Xylene
Benzene, Toluene, Xylene, Ethylbenzene
Dioxin, Lead, Cadmium, Mercury
Epichlorohydrfn
Lead & Arsenic Compounds, 1 ,3-outadiene
A-28
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
-------
Appendix B:
Methodology
Air Quality Data Base
The ambient air quality data presented in this report are
obtained from EPA's Aerometrie Information Retrieval
System (AIRS). These are direct measurements of
pollutant concentrations at monitoring stations
operated by state and local governments throughout the
nation. The monitoring stations are generally located
in the larger urban areas. EPA and other federal
agencies operate some air quality monitoring sites on
a temporary basis as a part of air pollution research
studies. The national monitoring network conforms to
uniform criteria for monitor siting, instrumentation,
and quality assurance.2
In 1994, more than 4,600 monitoring sites reported
air quality data for one or more of the six NAAQS
pollutants to AIRS. Air quality monitoring sites are
selected as national trends sites if they have complete
data for at least eight of the 10 years between 1985 and
1994. The annual data completeness criteria are
appropriate to each pollutant and measurement
methodology. Table B-l displays the number of sites
meeting the 10-year trend completeness criteria. For
the PM-10 standard which was established in 1987, the
trend analyses are based on sites with data in five of six
years present during the 1988-94 period. Because of
the annual turnover of monitoring sites, the use of a
moving 10-year window maximizes the number of
sites available for trends, and yields a data base that is
more consistent with the current monitoring network.
The air quality data are divided into two major
groupings: daily (or 24-hour) measurements and
continuous 1-hour measurements. The daily
measurements are obtained from monitoring
instruments that produce one measurement per 24-hour
period and typically operate on a systematic sampling
schedule of once every six days, or 61 samples per
year. Such instruments are used to measure PM-10 and
Pb. More frequent sampling of PM-10 (every other
day, or every day) is also common. Only PM-10
weighted annual arithmetic means that meet the AIRS
annual summary criteria are selected as valid means for
trends purposes.3 Only Pb sites with at least six
samples per quarter in three of the four calendar
quarters qualify as trends sites. Monthly composite Pb
data are used if at least two monthly samples are
available for at least three of the four calendar quarters.
Monitoring instruments that operate continuously
produce a measurement every hour for a possible total
of 8,760 hourly measurements in a year. For hourly
data, only annual averages based on at least 4,380
hourly observations are considered as trends statistics.
The SO2 standard-related daily statistics require 183, or
more, daily values to be included in the analysis.
Ozone sites meet the annual trends data completeness
requirement if they have at least 50 percent of the daily
data available for the ozone season, which varies by
state, but typically runs from May through September.11
Air Quality Trend Statistics
The air quality statistics presented in this report relate
to the pollutant-specific NAAQS and comply with the
recommendations of the Intra-Agency Task Force on
Air Quality Indicators.5 A composite average of each
of the trend statistics is used in the graphical
presentations throughout this report. All sites were
weighted equally in calculating the composite average
trend statistic. Missing annual summary statistics for
the second through ninth years for a site are estimated
by linear interpolation from the surrounding years.
Missing end points are replaced with the nearest valid
year of data. The resulting data sets are statistically
balanced, allowing simple statistical procedures and
graphics to be easily applied. This procedure also is
conservative since end-point rates of change are
dampened by the interpolated estimates.
Emission Estimates Methodology
Trends are presented for annual nationwide emissions
of CO, Pb, nitrogen oxides (NOX), volatile organic
compounds (VOCs), PM-10, and sulfur dioxide (SO2).
These are estimates of the amount and kinds of
pollution being emitted by automobiles, factories and
other sources, based upon best available engineering
calculations.
NATIONAL AIR QUALITY AND EMISSIONS TRENDS REPORT, 1994
B-l
-------
The estimates of emissions in this report differ
from those reported in previous reports due to
improvements in emission estimation methodologies.
Readers should also note that the 1990 to 1994
emission estimates are based on some preliminary data
and are subject to revision in future reports. Additional
emission estimates and a more detailed description of
the estimation methodology is contained in a
companion report, National Air Pollutant Emission
Trends, 1900-1994?
Table B-l: Number of monitoring sites
:-:-:: ;:<-::<-^:^<-:-:-:v:^^C'-o/:;l>l^T»l:-^^:
-------
TECHNICAL RiPORT DATA
(Please read Instructions an the reverse before completing}
1. REPORT NO.
EPA 454/R-95-014
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
5, REPORT DATE
National Air Quality and Emissions Trends Report, 1994
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
*.Muinuniai ft _ Wayland
A!. Freas, T. Fitz-Simons, J. Hemby, 0. Mintz, M..Schmidt,
H. Tanajian, C. Sansevero, R. Thompson, S, Nizich,
8, PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
U.S1 Environmental Protection Agency
Office of Air and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, NC 27711
1O. PROGRAM ELEMENT NO,
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
This report presents national and regional trends in air quality from 1985 through
1994 for particulate matter, sulfur dioxide, carbon monoxide, nitrogen dioxide, ozone
and lead. Air quality trends are also presented for 90 metropolitan, areas. Both
national and regional trends in each of these pollutants are examined. National air
quality trends are also presented for both the National Air Monitoring Sites (NAMS)
and other site categories. In addition to ambient air quality, trends are also
presented for annual nationwide emissions. These emissions are estimated using the
best available engineering calculations; the ambient levels presented are averages of
direct measurements. International comparisons of air quality and emissions are
contained in this report. The topics of air toxics and visibility are also addressed.
This report also includes a section call Selected Metropolitan Area Trends. Its
purpose is to provide interested members of the air pollution control community,
the private sector and the general public with greatly simplified air pollution
information for the single year 1994. Air quality statisticis are presented for each
of the pollutants for all Metropolitan Statistical Areas with data in 1994.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDiNTlFIEHS/OPEN ENDED TERMS
c. cos AT I Field/Group
Lead
Air Pollution Trends
Emission Trends
Carbon Monoxide
Nitrogen Dioxide
Ozone
Sulfur Dioxide
Total Suspended
Visibility
Particulate Matter
Air Pollution
Air Quality Standards
National Air Monitoriijig
Stations (NAMS)
Air Toxics
Pollutant Standards
Index
TEMENT
19. SECURITY CLASS (This Report I
21. NO. OF PAGES
Release Unlimited
20. SECURITY CLASS (Tin'spage/
22, RRtCE
EPA Form 2220-1 (Rov. 4-77) PREVIOUS EDITION is OBSOLETE
-------
INSTRUCTIONS
1. REPORT NUMBER
Insert (he EPA report number as il appeals on the cover of the publication,
2. LEAVE BLANK
3. RECIPIENTS ACCESSION NUMBER
Reserved far use by each report recipient.
4. TITLE AND SUBTITLE
Title should indicate clearly and briefly the subject coverage of the report,and be displayed prominently. Set sn!>(iik% if used, in smaller
type or otherwise subordinate it to main Mile. When a report is prepared in more than one volume, repeat tin- primary title, add vuluiru*
number and include subtitle for the specific liile.
S. REPORT DATE
Each report shall carry a daif indicating at least month and year. Indicate the hasis on which ii wns -wkeicii (e.g.. dale of issue, dale nf
approval, date of preparation, etc.).
6. PERFORMING ORGANIZATION CODE
Leave blank.
7. AUTHOR(S)
Give name(s) in conventional order (John K. Doe, J. Robert Doc. ere.}. List author's affiliation il' il ditlcts from the performing organi-
zation.
8. PERFORMING ORGANIZATION REPORT NUMBER
Insert if performing organization wishes to assign this number.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Give name, street, city, slate, and ZIP code. List no more than two levels or an organizational liirearcliy
10. PROGRAM ELEMENT NUMBER
Use the program element number under which the report was prepared. Subordinate numbers may be included in iiarciiilu'sct,
11. CONTRACT/GRANT NUMBER
Insert contract or pant number under which report was prepared.
12, SPONSORING AGENCY NAME AND ADDRESS
Include ZIP code.
13. TYPE OF REPORT AND PERIOD COVERED
Indicate interim final, etc,, and if applicable, dates covered.
14. SPONSORING AGtNCY CODE
Insert appropriate code.
Ii. SUPPLEMENTARY NOTES
Enter information not included elsewhere but useful, such as: Prepared in cooperation with. Translation of, I'roaik'd ai cuiileri-mx- »i.
To be published in. Supersedes, Supplements, etc.
16. ABSTRACT
Include a brief (200 words or less) factual summary of the most significant information contained rn the rcporl. It UK- report H>M|:IIII\ a
significant bibliography or literature survey, mention it here.
17. KEY WORDS AND DOCUMENT ANALYSIS
(a) DESCRIPTORS - Select from the Thesaurus of Engineering and Stai'ntilk Tcnns the proper autlmriwd terms thai identify the major
concept of the research and are sufficiently specific and precise to be used as index entries for cataloging.
(b) IDENTIFIERS AND OPEN-ENDED TERMS - Use identifiers for project names, code names, equipment designators, etc. Use «pim-
ended terms written in descriptor form for those subjects for which no descriptor exists.
(e) COSAT1 HELD GROUP - Held and group assignments are to be taken from the 1965 C'OSATI Subject < aiepory List. Since llie ma-
jority of documents are multidisciplinary in nature, the Primary Held/Group assignment!;,) will be specific discipline, area of human
endeavor, or type of physical object. The application!5) will be cross-referenced with secondary Held/(»ruup a
-------
INSTRUCTIONS
1. REPORT NUMBER
Insert the EPA report number as it appears on the covet of the publication.
2. LEAVE BLANK
3. RECIPIENTS ACCESSION NUMBER
Reserved for use by each report recipient.
4. TITLE AND SUBTITLE
Title should indicate deafly and briefly the subject coverage of the report, and be displayed prominently. Set subtitle, it' n«tl. in smaller
type or otherwise subordinate it to main title, when a report is prepared in more than on? volume, repeal the primary title, add volume
number and include subtitle for the specific title.
6. REPORT DATE
Each report shall carry a date indicating at least month and year. Indicate the hash an which ii was selected (e.g.. Jaic aj issue, datr of
approval, date of preparation, etc.).
6. PERFORMING ORGANIZATION CODE
Leave blank.
7. AUTHOR (S)
Give name(s) in conventional order fJolm K. Doe, J. Robert Doc, etc.}. List author's affiliation if it differs from Hie perfarminj! organi-
zation.
8. PERFORMING ORGANIZATION REPORT NUMBER
Insert if performing organization wishes to assign this number,
9, PERFORMING ORGANIZATION NAME AND ADDRESS
Give name, itreet, city, stale, and ZIP code. List no more than two levels of an organizational hircardiy.
10. PROGRAM ELEMENT NUMBER
Use the program element number under which the report wax prepared. Subordinate numbers may be indutlcil in |urviittie>es.
11. CONTRACT/GRANT NUMBER
Insert contract or grant number under which report was prepared.
12. SPONSORING AGENCY NAME AND ADDRESS
Include ZIP code.
13. TYPE OF REPORT AND PERIOD COVERED
Indicate interim final, etc., and if applicable, dales covered.
14. SPONSORING AGENCY CODE
Insert appropriate code.
Ii. SUPPLEMENTARY NOTES
Enter information not included elsewhere but useful, such as: Prepared in cooperation with. Translation of, 1'rcM.itii'U ul ctinli-iviiiv of.
To be published in. Supersedes, Supplements, etc,
16. ABSTRACT
Include a brief (200 words or less) factual summary of the most significant information i-untained in the report. II the rc|»irt i mil,mi', a
significant bibliography or literature survey, mention it here.
17. KEY WORDS AND DOCUMENT ANALYSIS
(a) DESCRIPTORS - Select from the Thesaurus of Engineering and Scientific Terms the proper uutliurixed terms (hat identify the major
concept of the research and are sufficiently specific and precise to be used as index entries for vatalugmg.
(b) IDENTIFIERS AND OPEN-ENDED TERMS - Use identifiers for project namts, code names, equipment designators, etc. Use open-
ended terms written in descriptor form for those subjects for which no descriptor exists.
(c) COSATI MELD GROUP - Held and group assignments ate to be taken from the 1 %5 C'OSATI Subject Caiirpnry List. Since the ma-
jority of documents are mullidisciplinary in nature, the Primary Held/Group assignments) will be .specific discipline, area of human
endeavor, or type of physical object. The application(s) will be cross-referenced with secondary Held/Group jsMpimems that will lollnu
the primary posting! s).
Ii. DISTRIBUTION STATEMENT
Denote reusability to the public or limitation for reasons other than security for example "Release Unlinirii-il." rite aiw availability to
the public, with address and price,
19.8.20. SECURITY CLASSIFICATION
DO NOT submit classified reports to the National Technical Information service.
21. NUMBER OF PAGES
Insert the total number of pages, including this one and unnumbered pages, but exclude distribution list, H any.
22. PRICE
Insert the price set by the National Technical Information Service or the Government Printing Office, it" knuwn.
EPA form 2220-1 (Rev. 4-77) (Reverse)
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
\. REPORT NO.
EPA 454/R-95-014
2.
3. RECIPIENT'S ACCESSION NO,
4, TITLE AND SUBTITLE
5. REPORT OATi
National Air Quality and Emissions Trends Report, 1994
6. PERFORMING ORGANIZATION CODE
7. AUTHOR^) |y| Wayland
«l. Freas, T. Fitz-Simons, 3. Hemby, 0. Mintz, M. Schmidt,
H. Tanajian, C. Sansevero, R. Thompson, S. Nizich,
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
J.Sl Environmental Protection Agency
3ffice of Air and Radiation
Dffice of Air Quality Planning and Standards
Research Triangle Park, NC 27711
ID, PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO,
12. SPONSORING AGENCY NAME AND ADDRESS
13, TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
This report presents national and regional trends in air quality from 1985 through
1994 for participate matter, sulfur dioxide, carbon monoxide, nitrogen dioxide, ozone
and lead. Air quality trends are also presented for 90 metropolitan areas. Both
national and regional trends in each of these pollutants are examined. National air
quality trends are also presented for both the National Air Monitoring Sites (NAMS)
and other site categories. In addition to ambient air quality, trends are also
presented for annual nationwide emissions. These emissions are estimated using the
best available engineering calculations; the ambient levels presented are averages of
direct measurements. International comparisons of air quality and emissions are
contained in this report. The topics of air toxics and visibility are also addressed.
This report also includes a section call Selected Metropolitan Area Trends. Its
purpose is to provide interested members of the air pollution control community,
the private sector and the general public with greatly simplified air pollution
information for the single year 1994. Air quality statisticis are presented for each
of the pollutants for all Metropolitan Statistical Areas with data in 1994.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTlFIERS/OPEN ENDED TERMS C. COSATl Field/Group
Lead
Air Pollution Trends
Emission Trends
Carbon Monoxide
Nitrogen Dioxide
Ozone
Sulfur Dioxide
Total Suspended
Visibility
Particulate Matter
Air Pollution
Air Quality Standards
National Air Monitoring
Stations (NAMS)
Air Toxics
Pollutant Standards
Iwte*
^TEMENT
19. SECURITY CLASS (This Report I
21. NO, OF PAGES
Release Unlimited
20. SECURITY CLASS (Tin'spages
22. PRICE
EPA Form 2220-1 (Rnv. 4-77) PREVIOUS EDITION is OBSOLETE
------- |