Approval and Promulgation of Air Quality Implementation Plans; Colorado; Emission Controls for Alfalfa Dehydrators

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[CO31-1-6012; FRL-4876-9]

Approval and Promulgation of Air Quality Implementation Plans;

Colorado; Emission Controls for Alfalfa Dehydrators

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rulemaking.

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SUMMARY: In this document, EPA is proposing to approve a revision to

the State Implementation Plan (SIP) submitted by the Governor of

Colorado on May 6, 1993. The Governor requested that Colorado

Regulation No. 5, which contained emission control regulations for

alfalfa dehydration plant drum facilities that had begun operation

prior to December 31, 1984, be removed from the federally-approved SIP.

The State made this request pursuant to the repeal of Regulation No. 5

from the State air quality regulations, which was mandated by

amendments to the State's laws relating to the regulation of

agricultural sources of air pollution. EPA is proposing to approve this

revision because the State provided a modeling demonstration which

showed that the removal of the emission limitations in Regulation No. 5

from the SIP would not interfere with attainment or maintenance of the

PM-10 National Ambient Air Quality Standards (NAAQS). The effect of

this approval, if promulgated, will be to remove the provisions of

Regulation No. 5 regarding existing alfalfa dehydrators from the

federally-approved SIP.

DATES: Comments on this proposed action must be received in writing by

May 23, 1994.

ADDRESSES: Written comments should be addressed to:

Vicki Stamper, 8ART-AP, U.S. Environmental Protection Agency,

Region VIII, 999 18th Street, suite 500, Denver, Colorado 80202-2466.

Copies of the State submittal and other relevant information are

available for public inspection during normal business hours at the

following locations:

Air Programs Branch, U.S. Environmental Protection Agency, Region

VIII, 999 18th Street, suite 500, Denver, Colorado 80202-2466.

Air Pollution Control Division, Colorado Department of Health, 4300

Cherry Creek Drive South, Denver, Colorado 80222-1530.

FOR FURTHER INFORMATION CONTACT: Vicki Stamper, 8ART-AP, U.S.

Environmental Protection Agency, Region VIII, 999 18th Street, suite

500, Denver, Colorado 80202-2466, (303) 293-1765.

SUPPLEMENTARY INFORMATION:

I. Background

In 1992, the Colorado Air Pollution Prevention and Control Act was

signed into law. This State Act significantly revised the previously-

existing Colorado statutory provisions relating to air quality,

including the regulation of agricultural sources of air pollution.

Specifically, Section 25-7-109(8) of the Colorado Revised Statutes

states that the State ``...shall not regulate emissions from

agricultural production such as farming, seasonal crop drying, animal

feeding, and pesticide application...'' unless such a source is

otherwise required to meet Federal requirements (e.g., construction or

operating permits, new source performance standards, etc.). Colorado's

Regulation No. 5 contained emission control regulations for existing

alfalfa dehydration plant drum facilities, which fall under the

category of seasonal crop drying. Because the State Air Quality Control

Commission is now prohibited from regulating air pollution emissions

from sources such as seasonal crop drying, the State repealed Colorado

Regulation No. 5 and requested that it be removed from the federally-

approved SIP.

Only one alfalfa dehydration plant drum facility in the State was

subject to Regulation No. 5. This plant is operated by the Graves Ranch

company in the vicinity of La Porte, Colorado, which is near the city

of Fort Collins in the northern Front Range area of the Colorado Rocky

Mountains. The plant only operates during the summer agricultural

season (June through October), and it is not currently considered to be

a major stationary source. Regulation No. 5 was repealed by the State

on March 18, 1993, resulting in the elimination of all State emission

control limits for this source. The State subsequently submitted a

request to remove Regulation No. 5 from the federally-approved SIP on

May 6, 1993.

Section 110(l) of the Clean Air Act (Act), as amended, prohibits

EPA from approving a revision to the SIP ``if the revision would

interfere with any applicable requirement concerning attainment and

reasonable further progress...or any other applicable requirement of

[the Clean Air Act].''1 Thus, in order for EPA to approve a

revision to a State's SIP, especially one which weakens or eliminates

an existing emission limitation, EPA must ensure that the revision will

not interfere with attainment or maintenance of the NAAQS. EPA informed

the State of this requirement in a March 16, 1993 letter during the

public comment period for the State's repeal of Regulation No. 5.

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\1\The Clean Air Act (``the Act'') is codified in the U.S. Code

at 42 U.S.C. 7401, et seq.

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II. Analysis of State Submission

1. Procedural Background

The Act requires States to observe certain procedural requirements

in developing implementation plans and plan revisions for submission to

EPA. Section 110(l) of the Act provides that each revision to an

implementation plan submitted by a State under the Act must be adopted

by such State after reasonable notice and public hearing.

The EPA must also determine whether a submittal is complete and

therefore warrants further EPA review and action (see section 110(k)(1)

of the Act and 57 FR 13565). The EPA's completeness criteria for SIP

submittals are set out at 40 CFR part 51, appendix V. (1992). The EPA

attempts to make completeness determinations within 60 days of

receiving a submission. However, a submittal is deemed complete by

operation of law if a completeness determination is not made by EPA 6

months after receipt of the submission.

After providing more than 30 days of prior public notice, the State

of Colorado held a public hearing on March 18, 1993 to entertain public

comment on the repeal of Colorado Regulation No. 5. The State

subsequently repealed the regulation from the Code of Colorado

Regulations and, on May 6, 1993, the Governor submitted a request that

Regulation No. 5 be removed from the federally-approved SIP. EPA

received the submittal on May 11, 1993.

The SIP revision was reviewed by EPA to determine completeness

shortly after its submittal, in accordance with the completeness

criteria set out at 40 CFR part 51, appendix V (1992). The submittal

was found to be administratively and technically complete, and a letter

dated July 8, 1993 was forwarded to the Governor indicating the

completeness of the submittal and the next steps to be taken in the

review process. EPA then proceeded to review the submittal for

technical adequacy.

2. Technical Adequacy Review

As noted, EPA had previously informed the State in a March 16, 1993

letter that EPA could not approve the removal of Regulation No. 5 from

the SIP without insuring that its repeal would not interfere with

attainment or maintenance of the NAAQS. The criteria pollutant (i.e.,

pollutant which is subject to the NAAQS) emitted from the Graves'

alfalfa dehydration plant of significance is PM-10 (those particles

with an aerodynamic diameter less than or equal to a nominal 10

micrometers). Currently, both La Porte and Fort Collins are designated

unclassifiable for the attainment status of the PM-10 NAAQS.2

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\2\The provisions of section 193 of the Act which prohibit

modification of certain control requirements in nonattainment areas

without offsetting equivalent or greater emissions reductions are

not applicable to this SIP revision.

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To address the section 110(l) noninterference requirement, the

State presented PM-10 ambient air quality monitoring data for the Fort

Collins and La Porte areas in its May 6, 1993 submittal. Specifically,

the State submitted PM-10 monitoring data collected in Fort Collins

during 1990 and in La Porte from May through December of 1992 which

showed that the PM-10 values in the area are generally one-third of the

NAAQS for PM-10. The State concluded that, because of these low values,

the repeal of the emission limitations on the Graves' alfalfa

dehydration plant would not interfere with attainment or maintenance of

the PM-10 NAAQS.

EPA reviewed the information submitted by the State and determined

that the monitoring data alone were insufficient to demonstrate that

the repeal of the emission limits in Regulation No. 5 would not

interfere with attainment or maintenance of the PM-10 NAAQS.

Specifically, in an August 30, 1993 letter, EPA informed the State that

these monitoring data were not adequate for the required demonstration

because: (1) The data did not necessarily reflect the uncontrolled

emissions from Graves' alfalfa dehydration plant (since Regulation No.

5 was still in effect at the time of the monitoring); and (2) EPA did

not review or approve the La Porte PM-10 monitor as a site of maximum

concentration. Consequently, EPA requested that the State submit a

modeling analysis based on the potential, uncontrolled emissions from

the Graves' alfalfa dehydration plant to demonstrate that the repeal of

the Regulation No. 5 emission limits would not interfere with

attainment or maintenance of the PM-10 NAAQS.

The State subsequently submitted the requested modeling

demonstration on September 24, 1993. The State utilized conservative

estimates for both the potential, uncontrolled PM-10 emissions from the

Graves' alfalfa dehydration plant, as well as the ambient PM-10

background concentration for the La Porte area, in an EPA-approved

screening model. The model predicted a worst case cumulative 24-hour

PM-10 concentration of 107 ug/m3 and a worst case cumulative

annual PM-10 concentration of 7.75 ug/m3 in the La Porte area. EPA

believes these values are sufficiently below the 24-hour PM-10 NAAQS of

150 ug/m3 and the annual PM-10 NAAQS of 50 ug/m3 to

adequately demonstrate that the repeal of Regulation No. 5 will not

interfere with attainment or maintenance of the PM-10 NAAQS. See the

Technical Support Document (TSD) accompanying this notice for further

details on the demonstration provided by the State.

III. Proposed Action

Based on the demonstration provided by the State on September 24,

1993 which showed that the repeal of Regulation No. 5 would not

interfere with attainment or maintenance of the PM-10 NAAQS, EPA is

proposing to approve the revision to the Colorado SIP submitted on May

6, 1993. The effect of this approval, if promulgated, will be to remove

the provisions of Regulation No. 5 regarding existing alfalfa

dehydrators from the federally-approved SIP.3

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\3\Note that the new construction or modification of alfalfa

dehydration plant drum facilities will continue to be regulated

under the State's prevention of significant deterioration (PSD) and

new source review (NSR) provisions, which are included in Colorado

Regulation No. 3.

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IV. Request for Public Comments

The EPA is requesting comments on all aspects of this proposal. As

indicated at the outset of this document, EPA will consider any

comments received by May 23, 1994.

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 any SIP shall be

considered separately in light of specific technical, economic, and

environmental factors and in relation to relevant statutory and

regulatory requirements.

Under the Regulatory Flexibility Act, 5 U.S.C. 600 et seq., 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, EPA may certify that the rule will not have a

significant economic impact on a substantial number of small entities.

Small entities include small business, small not-for-profit

enterprises, and government entities with jurisdiction over populations

of less than 50,000.

This proposed Federal SIP-approval of a regulatory relaxation does

not impose any new requirements. Accordingly, I certify 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 Act,

preparation of a regulatory flexibility analysis would constitute

Federal inquiry into the economic reasonableness of state action. The

Act forbids 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).

This action has been classified as a Table 2 action by the Regional

Administrator under the procedures published in the Federal Register on

January 19, 1989 (54 FR 2214-2225), as revised by an October 4, 1993

memorandum from Michael H. Shapiro, Acting Assistant Administrator for

Air and Radiation. A future document will inform the general public of

these tables. On January 6, 1989, the Office of Management and Budget

(OMB) waived Table 2 and 3 SIP revisions (54 FR 2222) from the

requirements of section 3 of Executive Order 12291 for a period of two

years. The EPA has submitted a request for a permanent waiver for Table

2 and 3 SIP revisions. The OMB has agreed to continue the waiver until

such time as it rules on EPA's request. This request is still

applicable under Executive Order 12866, which superseded Executive

Order 12291 on September 30, 1993.

List of Subjects in 40 CFR Part 52

Environmental protection, Air pollution control, Carbon monoxide,

Hydrocarbons, Incorporation by reference, Intergovernmental relations,

Lead, Nitrogen dioxide, Ozone, Particulate matter, Reporting and

recordkeeping requirements, Sulfur oxides, Volatile organic compounds.

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

Dated: April 8, 1994.

Jack McGraw,

Acting Regional Administrator.

[FR Doc. 94-9666 Filed 4-20-94; 8:45 am]

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