California Air Resources Board

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711

January 12, 1995

Mr. Peter D. Venturini, Chief
Stationary Source Division
Air Resources Board
State of California
2020 L Street
P.O. Box 2815
Sacramento, CA 95812

Dear Peter:

This letter provides a formal response to the draft prohibitory rule which you provided last summer and again in your letter of November 29, 1994. This draft prohibitory rule is intended to serve as a model prohibitory rule for the California districts and has been the subject of discussions among EPA, your agency and the California Air Pollution Control Officers Association (CAPCOA). We have previously stated that the approach and provisions of the draft rule are generally acceptable to EPA and that, when adopted by California districts and submitted to EPA, we intend to propose to approve the rule into the California State Implementation Plan. After reviewing the final draft, we remain committed to this position as discussed more fully below.

First, however, I want to thank you and your staff, especially Ray Menebroker, for the hard work and tenacity displayed in resolving the issues between EPA and the California districts. This draft rule represents a carefully crafted compromise that was largely designed by your office. The agreement we are confirming today would not have been possible without this help.

The proposed rule is designed to place smaller sources under annual emissions limits which restrict their "potential to emit" and thus their exposure to "major source" requirements of the Clean Air Act. The rule ensures compliance with the annual limit through a series of record keeping and reporting requirements. These requirements are tapered to reduce burdens as source size decreases. For instance, sources solely of attainment pollutants which limit their emissions to below 25 tons per year have no reporting requirement. For sources under 5 tons per year (or 2 tons per year for a single hazardous air pollutant), there is no specified record keeping or reporting requirements although these sources must still maintain sufficient records to demonstrate their compliance with the rule. To the extent possible, the record keeping requirements are itemized by source category and are designed to take advantage of records that sources are already likely to maintain. Through these measures, the rule should assure the public that the sources subject to the rule are properly maintaining their emissions below major source levels, while maximizing source flexibility and minimizing paperwork.

However, there are other safeguards built into the draft rule and in California's overall regulatory scheme which add to our confidence that the draft rule can work. The rule applies only to sources that agree to limit their emissions to 50 percent or less of the major source threshold. Sources with emissions above this level must either comply with all applicable "major source" requirements or secure a source-specific, federally-enforceable district permit (or other federally-enforceable mechanism) that properly limits emissions to levels below major source thresholds. Some sources may be able to qualify for an "alternative operation limit" which places simple operating limits on a source's combustion of fuel, sale of gasoline or use of a solvent. Because of the ease with which compliance can be tracked with operational limits, the rule allows sources using these limits to go up to 80 percent of the major source threshold. Either way, EPA believes that the rule creates a sufficient compliance buffer.

Moreover, California's extensive permit and inspection program increases EPA's confidence that the rule will prove adequate in limiting sources' emissions. California law requires upon annual renewal that each permit be reviewed to determine that the permit conditions are adequate to assure compliance with district rules and other applicable requirements. In addition, most California districts have an extensive inspection program so that compliance with the rule will be regularly checked by inspector visiting the source.

Finally, the rule is designed to provide smaller sources with a federally-enforceable means of limiting their potential emissions. The rule excludes sources that already have a federally enforceable operating permit and cannot be used to avoid complying with the State's new source review proqram.

Aside from these general observations, EPA has the following specific comments:

Section 2.7:  In a PM-10 nonattainment area, PM-10 precursors may need to be included when determining whether a source is major as required by section 189(e) of the Clean Air Act. Districts adopting this model rule should consider whether the definition of "Major Source" in section 2.7 should be augmented to include sources of PM-10 precursors.

Section 4.2(D):  The rule allows sources using air pollution control equipment to demonstrate compliance through the maintenance of general records on the unit and its operations. EPA has always been concerned with this provision since many pollution control units are only effective if specific operating procedures are followed. These specifics are best set and tracked in a source specific, federally-enforceable permit. For this reason, section 1.3 sunsets the applicability of the draft rule, after January 1, 1999, to pollution control equipment. For the coverage to continue beyond that date, a district must extend the provision. The EPA will disapprove the extension if the experience with the rule demonstrates that more specific conditions are needed to insure that pollution control devices are being used properly and continuously.

Section 4.2(E):  In general, EPA does not favor the use of generic or catch-all record keeping requirements for compliance purposes. There is a fear that the records necessary to show compliance for individual source categories will not be specified by the generic provision and thus will not be specified by the generic provision and thus will not be maintained. For this reason, EPA urges the Board and the Districts to evaluate regularly whether specific record keeping requirements should be developed for additional categories. As we noted during our negotiations, EPA will evaluate this question after the rule is in effect for three years and may seek -- through a SIP call or through other mechanisms -- to require additional record keeping requirements if there are implementation problems with this generic category. The districts may wish to add to the rule a provision which would authorize them to add record keeping requirements for additional source categories without a further SIP revision.

Again, thank you for staff on this draft rule. with you as this rule is all of the hard work by you and your staff on this draft rule. We look forward to continuing to work with you as this rule is adopted by California districts submitted to EPA for approval.

Sincerely,

Lydia N. Wegman, Deputy Director
Office of Air Quality Planning and Standards
Office of Air and Radiation
U.S. Environmental Protection Agency

cc:

James D. Boyd, CARB
Ray Menebroker, CARB
Richard Baldwin, Ventura AQMD
Rich Sommerville, San Diego AQMD
William Fray, South Coast, AQMD
Stuart Wilson, CAPCOA
Mary D. Nichols, EPA OAR
David Howekamp, Region 9