,,-i:.,a^5yF>,,^.^^^v.^,^;^
^.^^iyi^^tiaff&lims^nM^^i^^^^K^^^^M.
- ••*-- -„-'?. /•• .!i7"i- "-• *-— !t"- '.""^''rVt'K : '-i-VrA^x^^^'-'g^^-'^'- ^^J^^"-. ^B_ilLlL^: HL_i^^V^W"F^&- == ^ "V- ^:-•-'-•••• ^ ': = • =• v" ------,f-' ' -' -.,- ?-•••'- -•= s" --J»-^':'.- fv^-" ": •-.-.-, "*,•=- -'.",:=-•?.*%•;-' - -^-r--^;,.'^- ^ J^^.'^ "^•~,
£?V-?;/>:::i;e^^^^^
.-:,?: n;C;;^? -;;< ^&^^^%?:^fe^iySJ^S^apg^
".^^.-^-i-'-'vV."'•'•?* V;;J'Ay^\7^;'i^i-?/?^*>r^ .^ :^--:'>;':'i\';^' ••;:'-.•-'-''":."-.'''.>"''. vI'S'v-^-'-"'''-^^-'""'''-"^.'•''. >
'^|^M;^;w|if?|i;fii|^^
-------
-------
A Review of Air Quality Improvements in the
State of Iowa Under the Clean Air Act
Background
The first Clean Air Act promoting uniform laws and
cooperative activities between the states and the federal govern-
ment to control air pollution was approved in the Congress on
December 17, 1963. This law provided for grant funds to support
state, local, and multijurisdictional agencies in their efforts
to control air pollutant emissions. This Act was amended on
November 21, 1967. The 1967 Act established the statutory
concepts of air quality standards, air quality control regions,
and state implementation plans (SIP).
The Iowa legislature approved enabling legislation in 1967
placing air pollution control activities in the Iowa Department
of Health, and created the Iowa Air Pollution Control Commission.
The Commission was authorized to supervise the administration
and enforcement of laws relating to air pollution. The Commis-
sion had authority to adopt, amend, and promulgate rules and
regulations pertaining to air pollution control.
The state statute provided for local air pollution control
agencies, but required those agencies to obtain a "certificate
of acceptance" from the state air pollution Commission. This
certification was to assure that local agencies' operations
would be consistent with the state's program and give the state
authority over local program activities.
The 1967 Act required the Secretary of Health, Education,
and Welfare to identify air basins, both interstate and
intrastate. The Secretary was required to prepare air quality
criteria documents for pollutants of concern and companion
documents identifying control techniques. The states were to
use those criteria documents as guides for selecting air quality
standards which would protect against health and welfare effects
of the criteria pollutants. Under the authority of the 1967 Act,
the Department of Health, Education, and Welfare designated six
interstate and six intrastate air quality control regions in the
state of Iowa during 1970. Figure 1 shows the boundaries for
these regions.
The Environmental Protection Agency (EPA) was created in 1970
and was given responsibility for the air pollution control program.
The Clean Air Act of 1970 required the Administrator of
EPA to promulgate National Ambient Air Quality Standards (NAAQS)
and prepare guidelines the states would use to prepare plans for
attainment and maintenance of those standards. The NAAQS were
promulgated by EPA on April 30, 1971.
Table I contains the air quality standards for criteria
pollutants. The table includes total suspended particulate
matter (TSP) even though EPA replaced the TSP standard with PM10
-------
in 1987. The rationale for including TSP in this report is that
all states have long-term data, and those data show the change or
improvement in air quality over a long period of time* PM10 data
have only been gathered for a short period and any trends are not
yet apparent.
The states were required by Section 110 of the Act to submit
a plan showing attainment and maintenance of the NAAQS within
nine months of promulgation of the NAAQS. The Iowa plan was
submitted to EPA on January 27, 1972. EPA's approval of the Iowa
plan was published in the Federal Register on May 31, 1972, and
the approval became effective on that date. The Iowa SIP provided
for attainment and maintenance of standards for particulate
matter (TSP), sulfur oxides, nitrogen oxides, carbon monoxide
(CO), and photochemical oxidants (ozone). The Iowa SIP also
included an Emergency Episode Plan. That plan provided for
curtailment of emissions at certain source operations in the
event air quality levels increased to certain concentrations and
meteorological conditions were expected to contribute to air
stagnations for an extended period of time.
The state of Iowa revised its rules and regulations
subsequent to the plan submittal in 1972 to cure deficiencies
identified in the May 31, 1972, rulemaking. Additionally, there
have been reorganizations of the Iowa environmental programs
since the air program was created by statute as part of the Iowa
Department of Health. The reorganizations first created the
Iowa Department of Environmental Quality, then the Department
of Water, Air and Waste Management, and, finally, the present
Department of Natural Resources.
The Clean Air Act, as amended in 1977, added significantly
to the state and EPA responsibilities. The states were required
to identify areas in their jurisdiction where air quality was
worse than the NAAQS, equal to or better than the NAAQS, and
areas where there were insufficient air quality data to determine
their attainment status. EPA published a listing of those
areas as nonattainment, attainment, or unclassifiable. Table II
identifies the Iowa nonattainment areas designated in 1978. The
states were required to adopt and submit plans to attain and
maintain standards in the nonattainment areas. The Act also
contained requirements for prevention of significant deteriora-
tion (PSD) of air quality in areas meeting the national standards.
The 1977 amendments provided for certain sanctions if states did
not adopt or implement plans providing for attainment of the
standards.
Iowa's revised SIP under the requirements of the 1977
Clean Air Act Amendments was submitted on June 22, 1979. Those
revisions provided a strategy for attainment and maintenance of
standards in the nonattainment areas of the state. Among other
control measures, the plan required reasonably available control
technology (RACT) on all existing major sources in the nonattain-
ment areas. Additional revisions to the nonattainment plan
were submitted and acted on by EPA through 1980. The state also
-------
Total suspended
participate matter (TSP)
(standard was replaced
by PM10 in 1987)
PM1Q (July 1, 1987)
Sulfur Dioxide
Ozone (as revised
February 8, 1979)2
Table I
National Ambient Air Quality Standards
Primary
,1
75 pg/nr annual geometric mean
260 na/ar 24-hour value not to
be exceeded more than once per
year
50 jig/™ annual mean
150 /tg/m 24-hour average not
to be exceeded more than once
per year
80 /tg/m annual arithmetic mean
365 fig/m maximum 24-hour
concentration not to be exceeded
more than once per year
0.12 ppm (235 #g/m) 1-hour
average concentration not to
be exceeded more than once
per year
Secondary
150 /tg/m 24-hour value
not to be exceeded more
than once per year
Same as primary
1300 ftg/m maximum 3-hour
concentration not to be
exceeded more than once
per year
Same as primary
Carbon Monoxide
Nitrogen dioxide
Lead (October 5. 1978)
9 ppm (10 mg/m ) maximum
8-hour concentration not to
be exceeded more than once
per year
35 ppm (40 mg/m ) maximum
1-hour concentration not to be
exceeded more than once per
year
0.053 ppm (100 iig/m > annual
arithmetic mean
1.5
maximum arithmetic
mean averaged over a calendar
quarter
Same as primary
Same as primary
Same as primary
Primary standards are set to protect public health and secondary standards to protect public welfare.
The initial promulgation included photochemical oxidants and hydrocarbons. The photochemical oxidant
standard was revised to ozone in 1979 because the preponderance of photochemical oxidants measured is
ozone. The hydrocarbon standard was deleted in 1982. The hydrocarbon measurements included all organic
compounds. Hydrocarbons were measured as a precursor to ozone, but only reactive organic compounds
take part in the photochemical reaction producing ozone. The term "hydrocarbon" has been dropped and
replaced with the term "volatile organic compounds" (VOC) because not all hydrocarbons are reactive.
-------
Table II
Iowa Nonattairwent Area Designations (1978)
Primary Secondary
County JSP TSP Ozone1 CO SO,
Black Hawk P
Clinton P P
Lee P
Linn P
Marshall P
Muscatine P
Polk P P P
Pottawatomie P
Scott P P
Webster P
Woodbury P
Dubuque P
Ccrro Gordo P
P—Partial
W—Whole county
1 Lim, Polk, Scott, and Pottawatomie Counties were designated nonattainment but were removed from the list
when EPA revised the ozone standard in 1979.
adopted provisions requiring lowest achievable emission rates
for new sources in nonattainment areas. Later, the state adopted
provisions for best available control technology (BACT) in
attainment areas for prevention of significant deterioration of
air quality.
EPA promulgated a national ambient air quality standard for
lead on October 5, 1978. The state of Iowa submitted a lead SIP
August 19, 1980, which EPA approved March 20, 1981.
EPA promulgated a size specific particulate matter standard
(PM10), replacing the existing total suspended particulate matter
(TSP) standard July 1, 1987. The state submitted a SIP revision
reflecting the standard change October 28, 1988. EPA approved
the state's PM-^o SIP revision August 15, 1989. All remaining TSP
nonattainment areas were designated "unclassified" with respect
to the old standard.
Iowa's Air Quality Progress
The data discussion that follows is not to be construed to
be an exhaustive or detailed data analysis. An effort was made
to use data from 1974 through 1988 as an indication of air quality
changes or improvements. Where monitor sites were discontinued
and/or relocated, this was not possible. If a monitor was relo-
cated in the same general area in order to provide a continuing
overview, the new location was used to provide the continuity
sought. This has introduced some data bias; however, the intent
-------
is to merely illustrate continuing air quality changes over the
time period stated above. Where multiple monitor sites exist, a
single site somewhat representative of the overall air quality
of an area was selected. Some of the selected sites may not be
either a best or worst case site in an area.
Table III shows a chronological record of the redesignation
of areas in Iowa since the original areas were identified in
1978. These redesignations occurred primarily as a result of
changes in air quality. Most represent an improvement in the
status of the area,
Table III
Redesignation of Iowa Nonattainment Areas
Redesignation .
Area (County) : From To Date
Dubuque (Dubuque) Attainment CO nonattainment 1981
Keokuk (Lee) STSP Nonattainment Attainment 1981
Dubuque (Dubuque) SO^ Nonattainment Attainment 1982
South Central
Des Moines (Polk) PTSP Nonattainment Attainment 1982
Dubuque (Dubuque) CO Nonattainment Attainment 1982
Des Moines (Polk) PTSP Nonattainment PTSP (partial) 1984
and STSP Nonattainment
West Des Moines (Polk) PTSP Nonattainment STSP Nonattainment 1984
Davenport (Scott) PTSP Nonattainment STSP Nonattainment 1984
Cedar Rapids (Linn) PTSP Nonattainment STSP Nonattainment 1984
Ankeny (Polk) PTSP Nonattainment STSP Nonattainment 1984
Mason City (Cerro Gordo) PTSP Nonattainment PTSP (partial) 1984
and STSP Nonattainment
Mason City (Cerro Gordo) PM10 (Group II)1 1987
Cedar Rapids (Linn) PM1Q (Group II)1 1987
Des Moines (Polk) PM1Q (Group II)1 1987
All remaining TSP areas , PTSP and Unclassified 1989
STSP Nonattainment
PTSP—Primary TSP
STSP—Secondary TSP
After promulgating the PM1Q standard in 1987, EPA divided all areas of the country into three categories:
(1) areas with a strong likelihood of violating the standard (Group I); (2) areas where attainment of the
standards is possible (Group II); and (3) areas with a strong likelihood of attaining the standard (Group
III).
Particulate Matter (TSP and PM10)
Figure 2 shows the change in the annual geometric mean
TSP concentration from 1974 through 1988 for selected sites in
Council Bluffs, Cedar Rapids, Des Moines, and Mason City.
Figure 3 shows the second maximum 24-hour concentration
changes from 1974 through 1988 for Council Bluffs, Cedar Rapids,
-------
Des Moines, and Mason City. These second maximum values illus-
trate violations of the primary and secondary 24-hour TSP
standard. The standard allows one exceedance per year; thus,
the second maximum value is an indicator of air quality standard
violations. Generally, the number of exceedances of the standard
decreased with the improved air quality.
Figure 4 illustrates the second maximum 24-hour PM10 values
for Council Bluffs, Cedar Rapids, Des Moines, and Mason City.
The second maximum is used because the standard allows one
exceedance. Cedar Rapids, Des Moines, and Mason City are PM10
group II areas. Group II areas are those expected to attain the
PM10 standard, but some uncertainty exists. The remainder of
the state is Group III. Group III areas are those fully expected
to be within the PM10 standard.
Since the state began measuring PM-^g concentrations, no
violations of the new standard have been measured.
Sulfur Dioxide (SO2)
Measured exceedances of the short-term standards (24-hour
and 3-hour) have been recorded, but showing long-term air quality
trends in Iowa is difficult since few monitors have remained in
the same location for more than approximately five years. Addi-
tionally, the SO2 monitoring method was changed in the late 1970s
from a 24-hour bubbler method to a continuous method. Continuous
and 24-hour bubbler results do not compare well. There are only
a few areas in Iowa where there are measured exceedances of the
24-hour and 3-hour standard. The large majority of SC>2 monitor
sites have never measured any SO2 exceedances. Figure 5 shows
the second maximum 24-hour values for selected sites, and Figure
6 shows 3-hour values for SO2.
Carbon Monoxide (CO)
The ambient air quality standards for CO are 9 parts per
million (ppm) 8-hour average not to be exceeded more than once
per year, and 35 ppm 1-hour average not to be exceeded more
than once per year. In the mid-1970s, Dubuque, Cedar Rapids,
and Des Moines experienced exceedances of the CO standard.
Since there were no major point sources in these cities, the
CO concentrations were believed to come from mobile sources.
There were no exceedances of the 1-hour standard, but several
exceedances of the 8-hour standard were measured in each of the
above-mentioned cities. Figure 7 shows the second maximum 8-hour
average concentrations for each of those cities.
Ozone
The ozone standard is 0.12 ppm 1-hour average. Violations
occur when the expected exceedances are greater than one per
year. Some violations occurred in Cedar Rapids in 1977 and 1978,
but none have been reported since. Elsewhere in the state there
-------
have been isolated single exceedances but no reported violations.
Figure 8 shows the second maximum 1-hour concentrations for
Cedar Rapids, Des Moines, and Iowa City.
Nitrogen Dioxide
The nitrogen oxides measurements in Iowa began in 1976 and
were discontinued after 1981 because the nitrogen oxides' concen-
trations were so far below the standard. First, there is no
ozone problem in any of the major cities so that NOX contribu-
tions to ozone is not a concern. Secondly, monitoring for NOX
where there is so little requires an unreasonable expenditure of
resources. No figure showing NOX concentrations is included in
this paper.
Lead
EPA promulgated the NAAQS for lead on October 5, 1978. The
lead standard is 1.5 micrograms (jug) per cubic meter (m3) and
is both primary and secondary. Air sampling for lead began in
various parts of Iowa in 1974 and has continued through the
present. Only one quarterly mean greater than the 1.5 ng/m?
standard has been reported, which was in Council Bluffs in 1982.
It is generally believed that that value was due to transport
from lead sources in Nebraska. Abatement actions have been taken
to limit lead emissions from those sources and the air quality
measurements tend to reflect those activities.
Figure 9 shows the measured quarterly averages from
Council Bluffs. Figure 10 is Des Moines from 1979 through 1988,
where available.
Summary
The reduction of particulate matter concentrations in Iowa
is the single greatest air quality improvement statewide. The
1963 and 1967 Acts catalyzed air pollution control activities,
but the national ambient air standards conceived by the 1970
Clean Air Act and the resulting state implementation plans
provided the real beginning to improved air quality in the state
of Iowa. Most of the air quality improvement followed the nonat-
tainment plans required by the Clean Air Act, as amended in 1977.
The 1977 amendments required RACT in certain areas and BACT in
others. These requirements in part account for the control of
major pollutant sources.
Clinton and Keokuk are the only areas in which measured
SO2 violations have been found. These were discovered in the
mid-1980s because of an expanded SO2 monitoring program. Keokuk
has had no SO2 standard violations since 1985. The state has
prioritized its program to reduce SO2 emissions in Clinton and
to evaluate SO2 levels in other parts of the state.
-------
All areas of Iowa are now attainment for CO. Measured CO
violations were found in Cedar Rapids in 1975 and 1976. CO
violations were found in Des Moines from 1976 through 1984. The
federal motor vehicle pollution control program, in conjunction
with traffic flow improvements and traffic reduction techniques,
have improved CO air quality in those areas that have experienced
CO violations. Dubuque also experienced CO violations in 1980,
1983, and 1984. Motor vehicle pollution controls and transporta-
tion control techniques reduced CO levels to below the standard.
Cedar Rapids and Des Moines experienced ozone violations
in 1977 and 1978. Since that time there have been no exceedances
of the standard. Generally, Iowa has had no ozone problems.
Nitrogen oxides concentrations are so low in Iowa that
monitoring for the most part has been eliminated as an
unnecessary expense.
Ambient lead levels in the urban areas of Iowa appear
related to motor vehicle emissions except for Council Bluffs.
Observations of the ambient lead monitoring in Des Moines from
1979 through 1987 suggests that as unleaded gasoline use
increased, ambient lead concentrations decreased. A similar
pattern is found in Council Bluffs, but it appears that a
stationary lead source keeps the lead concentrations elevated.
However, there has only been one violation of the lead standard
in Council Bluffs and that was the first quarter of 1982.
The Clean Air Act of 1967 provided funding to start up or
expand state air pollution control programs, but the 1970 and
1977 amendments provided the structure needed to develop strong
and effective programs. The 1977 amendments contained require-
ments for areas not attaining the NAAQS to institute more
stringent emissions controls to meet the standards, as well as
provisions intended to prevent violations in areas with air
quality equal to or better than the NAAQS. The Clean Air Act has
directly influenced activities which have benefited air quality
in Iowa.
8
-------
Scg . *
a: u. S? «K o:
m
CB
I
CO
O)
0)
CC
O
O
co
O
0)
•H
fa
-------
-------
cu
LLJ
DC
LL
CO
CO
CD
CXD
00
CM
oo
co
CO
co
CD
_o
"CD
o
CD
O
oo
"co
13
C
a.
co
00
CD
b
c
o
CO
CO
D
CO
(D
I
CD
"O
Z3
O
O
(£W/6n)
-------
-------
ooooooooooooooo
co
CO
.o
I
CD
O
C
O
O
Q_
CO
13
O
3
CM
I
1
CM
O
o
CO
CD
'O
CO
CD
Q
CO
2
"a.
co
DC
CO
I
CD
'o
c
o
O
feiu/6n)
-------
-------
LU
DC
CO
CD
o
5
CM
T3
JZ
CM
b
o
CO
CO
CO
-------
-------
LO
LU
DC
LL
o
CD
00
O)
o S
= 8
05
CD
O
c
o
O
CM
O
CO
•s 2
1_
T-I CD ™
f c"5
C -= CD
CO^ D
•00)'^
® OS C
J o O
.E o o
O i_ i_
w .2 2
~c^ *•• ^^
^IB VH
'55 ^ ^
O
I
CM
E o^^
^ = CD CD
* + =tfc
-------
-------
CO
LU
CL
Li-
•£
CO
o
CM
O
CO
I
CO
oo
oo
<£>
00
CO
oo
CM
oo
CO
O
CD
O
O
O
CM
O
CO
O
CO
oo
O
O
CO
CM
ooooooooooooooooo
oooooooooooooooo
in
oo
£S
.g -
TJ O
CD *-
S 1
^ Q-
£ w
E -Q
c. 4-<
CO CO
Q) -^
C3)
CD
O
O
O
•o
1^
-3 co
c ^
§a
CO
TD
CO
E
1 E
CD
.1 i
Ss
si
SI
CO .Q
o
-------
-------
LU
DC
LL
CO
OD CO
C\J
.O
I
-------
-------
00
LLJ
cc
LL
CO
CO
CD
CO
^t
00
CM
CO
O
co
CO
1^
CD
N.
s
OCOCD^OJOCOCDTrCMO
CNI i- i- i- i- i- O O O O ' p
OCJCDCDCDOOCJCDCDC)
(UJdd)
05
CO
o
'I-
•«—•
(D
O
c
o
O
0
c:
*o
&
E
13
C
-------
-------
CD
LLJ
DC
LJL
CO
CD
O)
£
I
T3
CO
CD
CD
•c
CO
O
CO
It:
m
"o
o
O
co
O
f
0
co
O
•o
cr5
CD
•4—*
co
O
CVJ
6
CO
O
i- i- O
-------
-------
LU
CC
O
5
co
O
0)
CO
O
•O
CO
0
•c
CO
O
4—1
CO
(ew/6n)
-------
------- |