# Approval and Promulgation of Implementation Plans; State of Iowa

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URL: https://www.frixlaw.com/law-library/documents/fr%3A97-21696

## Record

- **Collection:** Federal Register
- **Document type:** Proposed Rule
- **Published:** August 15, 1997
- **Citation:** 62 FR 43681

## Text

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[IA 031-1031; FRL-5875-5]

Approval and Promulgation of Implementation Plans; State of Iowa

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The EPA is proposing to approve the State Implementation Plan
(SIP) submitted by the state of Iowa to achieve attainment of the
primary National Ambient Air Quality Standard (NAAQS) for sulfur
dioxide (SO2) for Muscatine County, Iowa. The SIP was
submitted to satisfy the requirements of section 110 and part D of
title I of the Clean Air Act (Act), and regulates certain sources of
SO2 emissions in Muscatine, Iowa. The effect of the EPA's
proposed action is to make this revision to the Iowa SIP federally
enforceable.

DATES: Comments must be received on or before September 15, 1997.

ADDRESSES: Comments may be mailed to Wayne Kaiser, Environmental
Protection Agency, Air Planning and Development Branch, 726 Minnesota
Avenue, Kansas City, Kansas 66101.

FOR FURTHER INFORMATION CONTACT: Wayne Kaiser at (913) 551-7603.

SUPPLEMENTARY INFORMATION:

I. Background

On March 10, 1994, the EPA published a document in the Federal
Register (59 FR 11193) designating a portion of Muscatine County, Iowa,
nonattainment for SO2. Additional information on the events
leading to nonattainment designation are contained in the Technical
Support Document (TSD) which accompanied that document.
Areas designated nonattainment are subject to section 110 and part
D of title I of the Act. On June 13, 1996, and April 25, 1997, the
state of Iowa submitted information satisfying these requirements. An
evaluation of the adequacy of this submittal with the Federal
requirements is discussed below.

II. Description and Analysis of State Submittal

In 1991 and 1992 there were violations of the primary
SO2 NAAQS at one of three state air monitors in Muscatine,
Iowa. This resulted in designation of a portion of Muscatine County as
nonattainment in 1994. The state determined that there were two major
emission sources contributing to the violations of the NAAQS. They were
Grain Processing Corporation (GPC), a wet grain milling facility, and
Muscatine Power and Water (MPW), a municipal power plant. In the course
of modeling the impacts of these emission sources, it was also
determined that a third source, Monsanto Corporation, contributed to a
modeled violation of the SO2 NAAQS in the vicinity of its
own facility.
The state of Iowa's Department of Natural Resources negotiated
emission reductions with GPC, MPW, and Monsanto. The reductions were
incorporated into revised construction permits. These permits have been
submitted as a part of the section 110 SIP revision and thus will be
federally enforceable when approved by the EPA.
The normal process for establishing a control strategy for an area
where a NAAQS violation has occurred is to conduct an air dispersion
modeling analysis to determine the degree of emissions reductions
required by the sources contributing to the monitored violations.
The NAAQS violations occurred at the Musser Park monitor, which is
located north of and nearest to the GPC facility. Two additional
monitors, one located further north of the sources, and one located to
the south near MPW, have never recorded any violations of the NAAQS.
Dispersion modeling performed by the state using the EPA's
Industrial Source Complex (ISC) model significantly under predicted
monitored values at the Musser Park monitor, but was highly accurate at
the other downwind monitoring site. Consequently, the state initially
used an alternative methodology, roll-back analysis, to estimate
emission rates needed to attain the NAAQS at the Musser Park monitoring
site. A roll-back analysis takes a monitored ambient exceedance
recorded during a specific set of facility operating conditions and
determines the amount of the exceedance due to each of the source's
SO2 emitting operations in use at that time. The estimates
are then linearly ``rolled back'' to acceptable SO2 emission
limits which provide for attainment of the NAAQS under that set of
operating conditions. Ultimately, the state, GPC, and MPW negotiated
reductions of allowable emissions of 24 percent and 60 percent,
respectively, and reductions of actual emissions of 4 percent and 13
percent, respectively. These emission reductions were incorporated into
revised construction permits for each source. These permits are
proposed for approval as part of this

[[Page 43682]]

SIP revision and thus will be federally enforceable. The TSD for this
action contains further information on the modeling analysis and the
establishment of the final emission limits.
Although the ISC model was not sufficiently accurate to be the
basis for the control strategy at GPC and MPW, it was judged to be
reliable for predicted emissions in the vicinity of the Monsanto
facility. Modeling here indicated one small area of nonattainment on
plant property to which the public had access. Monsanto agreed to
accept emission limits and operating conditions in its permits to
eliminate the modeled exceedances of the SO2 NAAQS.
The emission limits imposed upon the sources are contained in the
following permits:

GPC Permits dated September 18, 1995: #95-A-374; Boilers 1,2,3,5,6,7,
#74-A-015-S; Source 97, Wet Milling No. 3 Germ Drier, #79-A-194-S;
Source 15, Wet Milling Nos. 1 and 2 Germ Driers, #79-A-195-S; Source
126, Wet Milling No. 4 Germ Drier. Permit #95-A-374 contains the
requirement for the installation of a continuous emission monitor (CEM)
on the stack servicing the permitted boilers.
MPW Permits dated September 14, 1995: #74-A-175-S; Boiler 7, #95-A-373;
Boiler 8. Permit #74-A-175 requires the installation of a CEM on boiler
stack 7. The CEMs provide for continuous measurement of SO2
emissions and the subsequent determination of compliance with the
permit emission limits. All permits contain the state's standard
notification, recordkeeping, and reporting requirements.
Monsanto Permits dated July 18, 1996: #76-A-265-S3; B-6 Boiler, and
#76-A-161-S3; B-7 Boiler.

III. Nonattainment Plan Provisions (Part D, Section 172(c))

The following discusses how the submission complies with the
pertinent provisions of the General Preamble for Implementation of
title I of the 1990 Amendments and the SO2 Guideliine
Document, as well as section 172(c) of the Act, which sets forth the
requirements for part D SO2 SIPs.
Section 172(c)(1)--In General. The plan complies with the
requirements to implement reasonably available control measures by
providing for expeditious attainment of the SO2 NAAQS
through the emission limits imposed on the sources by enforceable
permits.
Section 172(c)(2)--Reasonable Further Progress (RFP). Section
171(l) of the amended Act defines RFP as ``such annual incremental
reductions in emissions of the relevant air pollutant as are required
by (part D) or may reasonable be required by the EPA for the purpose of
ensuring attainment of the applicable national ambient air quality
standard by the applicable date.'' As discussed in the General Preamble
for SO2 (57 FR 13547), there is usually a single ``step''
between precontrol nonattainment and postcontrol attainment. Therefore,
for SO2, with its discernible relationship between emissions
and air quality and significant and immediate air quality improvement,
RFP is construed as ``adherence to an ambitious compliance schedule.''
The state has met the requirement to implement reasonably available
control measures and RFP by providing for expeditious attainment of the
SO2 NAAQS through the establishment of emissions limits and
operating restrictions imposed on the sources by the state construction
permits submitted as part of the state plan. Implementation plans
required under section 191(a) shall provide for attainment as
expeditiously as practicable but no later than five years from the date
of the nonattainment designation, in this case by March 1999. However,
the state permits required compliance (and attainment) by March 15,
1996. The sources met this compliance date, and the EPA believes that
this date was as expeditious as practicable.
Section 172(c)(3)--Inventory. This section of the Act requires that
nonattainment plan provisions include a comprehensive, accurate,
current inventory of actual emissions from all sources of relevant
pollutants in the nonattainment area. The emission inventory also
should include a comprehensive, accurate, and current inventory of
allowable emissions in the area.
A detailed emission inventory was included in the states
submittal. In order to better quantify actual emission from the 100
``nontraditional'' sources at GPC, source testing was conducted on two
occasions on a number of representative emission points. In addition to
the four major sources in the area, an emissions inventory was obtained
for modeling purposes from three additional minor sources in Muscatine,
and from 36 sources outside of Muscatine but within 50 kilometers.
Section 172(c)(5)--Permits for New and Modified Major Stationary
Sources. Section 172(c)(5) and section 173 of the amended Act contains
SIP requirements for state construction permitting programs. Any new or
modified major stationary source constructed in a nonattainment area
must comply with the state submitted and federally approved New Source
Review (NSR) Program. The state has an approved NSR program. However,
revisions were required to make the state rules compliant with the 1990
Amendments. The state adopted revisions and the EPA approved them in
Federal Register documents dated June 23, 1995, and October 30, 1995.
The EPA action proposing approval of the state's emission offset rule
has been published and a final action is pending.
Section 172(c)(6)--Other Measures. This section states that SIP
provisions shall include enforceable emission limitations, and such
other control measures, means or techniques, as well as schedules and
timetables for compliance as may be necessary, to provide for
attainment by the applicable attainment date.
The state SIP provides for expeditious attainment of the
SO2 NAAQS through the emission limits and operating
restrictions that are set forth in the permits issued by the state. The
emission reductions contained in these documents should ensure that the
area continues to attain the NAAQS.
Section 172(c)(7)--Compliance with Section 110(a)(2). This section
contains general requirements for nonattainment plans. The state has
met these requirements. The SIP contains enforceable permits which
ensure attainment of the NAAQS. The state has committed to continue its
existing ambient monitoring network; it has an approved parts C and D
permit program (final approval of the state's emission offset rule is
pending); and it has authority to prevent construction of a source
which will contribute significantly to nonattainment in, or interfere
with maintenance by, any other state with respect to the NAAQS. It also
has demonstrated it has adequate personnel, funding, and authority
under state law to carry out the provisions of the SIP. With respect to
section 110(a)(2)(K), under which the EPA generally requires modeling
in the case of SO2 and other pollutants (to demonstrate
attainment as required by other provisions of section 110(a) and part
D), the EPA notes that the ISC model used by the state has been shown
to under predict ambient SO2 concentrations at the Musser
Park monitor on known exceedance days. Therefore, as described in more
detail above, a negotiated reduction of the permitted emission limits
was established.
Section 172(c)(8)--Equivalent Techniques. This section provides
that

[[Page 43683]]

the EPA may allow the state to use equivalent modeling, emission
inventory, and planning procedures in its SIP unless the EPA determines
they are less effective than procedures approved by the Administrator.
Since attainment of the SO2 NAAQS could not be demonstrated
for all portions of the nonattainment area by modeling (for technical
reasons described above and in more detail in the TSD), reductions in
both allowable and actual limits were determined for the affected
sources based generally on rollback calculations. The EPA believes that
this procedure is no less effective than other procedures approved by
the Administrator since it results in enforceable reductions in both
potential and actual emissions. In addition, although not a basis for
approval of the attainment demonstration, the EPA notes that no
monitored violations of the NAAQS have been recorded since the
reductions have been implemented.
Section 172(c)(9)--Contingency Measures. For SO2
programs, the EPA interprets ``contingency measures'' to mean that the
state agency has a comprehensive program to identify sources of
violations of the SO2 NAAQS and to undertake an aggressive
follow-up for compliance and enforcement, including expedited
procedures for establishing enforceable consent agreements pending
adoption of revised SIPs.
The state has a comprehensive program to identify sources of
violations of the SO2 NAAQS and to undertake an aggressive
follow-up for compliance and enforcement. The state has statutory
authority to address any exceedances and resultant violations of the
NAAQS that may be identified.
The state will continue to maintain the network of the three
SO2 ambient air monitoring stations in the nonattainment
area. The state is committed to quickly identifying when exceedances
occur and evaluating which sources may be contributing to such
occurrences. Direct source monitoring, using CEMs as required in the
permits issued to MPW and GPC under this plan, is designed to ensure
that the emissions limitations in the permit are not exceeded.
Reporting requirements established in those permits provide the state
with a mechanism to consistently monitor the operations of those
sources.
Section 176(c)--Conformity. The EPA promulgated final general
conformity regulations on November 30, 1993. These regulations require
the states to adopt general conformity provisions in the SIPs for areas
designated nonattainment or subject to a maintenance plan approved
under section 175A of the Act. The state submitted its general
conformity SIP, which the EPA approved on October 25, 1995. The state
is not subject to the transportation conformity requirements.
The state complied with the procedural requirements for submittal
of SIPs pursuant to sections 110(a) and 110(l). The state provided for
public notice and comment as required. The permits were approved by the
Iowa Environmental Protection Commission. The SIP and related
documentation was submitted by the governor's designee to the EPA on
June 13, 1996, and April 25, 1997.
The SIP submittal was reviewed by the EPA to determine completeness
in accordance with the completeness criteria set out in 40 CFR part 51,
appendix V. The submittal was found complete and the state was so
notified by an EPA letter dated July 16, 1996.

IV. Proposed Action

The EPA is proposing to approve a revision to the state SIP which
incorporates emission restrictions and limitations on major
SO2 sources in Muscatine, Iowa, for the purpose of assuring
attainment and maintenance of the SO2 NAAQS. The enforceable
permit conditions have been in effect since March 15, 1996. There have
been no exceedances of the NAAQS since September 1995.
Nothing in this action should be construed as permitting or
allowing or establishing a precedent for any future request for
revision to any SIP. Each request for revision to the SIP shall be
considered separately in light of specific technical, economic, and
environmental factors, and in relation to relevant statutory and
regulatory requirements.

V. Administrative Requirements

A. Executive Order 12866

The Office of Management and Budget has exempted this regulatory
action from Executive Order 12866 review.

B. Regulatory Flexibility Act

Under the Regulatory Flexibility Act, 5. U.S.C. 600 et seq., the
EPA must prepare a regulatory flexibility analysis assessing the impact
of any proposed or final rule on small entities (5 U.S.C. 603 and 604).
Alternatively, the EPA may certify that the rule will not have a
significant impact on a substantial number of small entities. Small
entities include small businesses, small not-for-profit enterprises,
and government entities with jurisdiction over populations of less than
50,000.
SIP approvals under section 110 and subchapter I, part D of the CAA
do not create any new requirements but simply approve requirements that
the state is already imposing. Therefore, because the Federal SIP
approval does not impose any new requirements, the Administrator
certifies that it does not have a significant impact on any small
entities affected. Moreover, due to the nature of the Federal-state
relationship under the CAA, preparation of a regulatory flexibility
analysis would constitute Federal inquiry into the economic
reasonableness of state action. The CAA forbids the EPA to base its
actions concerning SIPs on such grounds (Union Electric Co. v. U.S.
E.P.A., 427 U.S. 246, 256-66 (S.Ct. 1976); 42 U.S.C. 7410(a)(2)).

C. Unfunded Mandates

Under section 202 of the Unfunded Mandates Reform Act of 1995
(``Unfunded Mandates Act''), signed into law on March 22, 1995, the EPA
must prepare a budgetary impact statement to accompany any proposed or
final rule that includes a Federal mandate that may result in estimated
costs to state, local, or tribal governments in the aggregate; or to
private sector, of $100 million or more. Under section 205, the EPA
must select the most cost-effective and least burdensome alternative
that achieves the objectives of the rule and is consistent with
statutory requirements. Section 203 requires the EPA to establish a
plan for informing and advising any small governments that may be
significantly or uniquely impacted by the rule.
The EPA has determined that the approval action proposed does not
include a Federal mandate that may result in estimated costs of $100
million or more to either state, local, or tribal governments in the
aggregate, or to the private sector. This Federal action approves
preexisting requirements under state or local law, and imposes no new
requirements. Accordingly, no additional costs to state, local, or
tribal governments, or to the private sector, result from this action.

Authority: 42 U.S.C. 7401-7671q.

Dated: July 24, 1997.
William Rice,
Acting Regional Administrator.
[FR Doc. 97-21696 Filed 8-14-97; 8:45 am]
BILLING CODE 6560-50-F

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A97-21696. Public record. Not legal advice.