Technical Support Document for EPA's Notice of Proposed Rulemaking

on revisions to the California State Implementation Plan as submitted by

the State of California for the Monterey

Bay Unified Air Pollution Control District EPA's Analy sis of Monterey Bay Unified Air Pollution Control District = s Rule 400 - Visible Emissions United States Environmental Protection Agency , Region IX

Air Division January 2010 Prepared by

Andrew SteckelMonterey Bay UAPCD

– Rule 400,

Visible Emissions TSD, January 10 - 2 - Monterey Bay Unified Air Poll ution Control District ( MBUAPCD ) Rule 400 - Visible Emissions 1. Rule A doption and Submittal Chronology - On August 11, 2005 (70 FR 46770), EPA in corporated into the SI P a version of MBUAPCD Rule 400 that was adopted locally on October 15, 2003, and subm itted to EPA on January 15, 2004 . No subsequent version of the rule was submitted besides the December 15, 2004 version that is described below and is the subject of this technical support document.

- On December 15, 2004, the MBUAPCD G overn ing Board ame nded Rule 400 .

- On March 7, 2008, the California Air Resources Board (CARB) submitted the December 2004 amended Rule 400 to EPA as a revision to the California State Implementation Plan (SI P).

- On April 17, 2008 , EPA found complete C alifornia’ s March 2008 submittal of Rule 400 . 2. Rule Summary & Background - MBUAPCD R ule 400 is designed to limit visible emissions from various a ctivities and sources , primarily by establishing a 20% opacity standard. The December 2004 amendment ad ded a definition of “startup” in section 2.5 and relaxed the opacity requirement for gas turbines to allow 40% opacity during startup. Specifically , new section 3.2.3 reads, “...visible emissions from gas - fired combustion turbines may exceed Ringlemann 1 during startup, provid ed that visible emissions during such startups shall not exceed Ringelmann 2 (or equivalent 40% opacity

) for a period or periods aggregating more than three minutes in any one hour.” 3. Nonattainment History of Monterey Bay Air Basin - Upon enactment o f the Clean Air Act (CAA) Amendments of 1990, the Monterey Bay air basin was designated nonattainment for ozone and classified as moderate under CAA § 107(d)(4)(B) . However, o n October 18, 2000, the area was designated attainment for the 1 - ho ur ozone stand ard. T he area also meets the 8 - hour ozone standard , was designated attainment for PM - 10 , and meets the PM - 2.5 standard. 4. Rule Evaluation - EPA is primarily using the following three criteria to evaluate Rule 400. a. Rule Stringency

– CAA §§ 172( c ) and 182( b )(2) require ozone nonattainment areas to implement reasonably

available control technology (RACT) for ozone precursors. In approving the Monterey

Bay Ozone Maint enance Plan, EPA found that MBUAPCD had adequately implemented RACT . Because Mont erey Bay attained the PM standard, the area was not subject to CAA § 189 PM requirements regarding Reasonably or Best Available Control Measures (RACM or BACM) . b. Enforceability

– CAA § 110(a)(2)(A) requires that regulations submitted to EPA for SI P appro val must be clear and legally enforceable.Monterey Bay UAPCD

– Rule 400,

Visible Emissions TSD, January 10 - 3 - c. Anti - Backsliding - CAA § 110(l) restricts certain SIP revisions that would relax existing SI P approved requirements. EPA finds that Rule 400 reasonably fulfills these three criteria except for the rule def iciency identified below. 5 . Rule Deficienc y - T he SI P submittal fails to demonstrate that this rule revision adequately complies with CAA requirements regarding enforceability and anti - backsliding as described below.

- New section 3.2.3 places no time limitation on o pacity between 20% and 40% for gas turbine s except as defined in the District permit pursuant to new section 2.5. This is inconsistent with long - standing national policy on excess emissions (see attachment 8.c below), which explains that SI P rules must ensure that emissions during startup conditions are minimized. We believe this could be addressed by adding rule text establishing appropriate time limitations on gas turbine startup, requiring sources to minimize time and emissions d uring startup , and demonstrating in the staff report that the rule minimizes emissions during startup . 6. Additional Recommendations for the Next Rule Revision - The following revision is not currently the basis for rule disapproval, but is recommended f or the next time the rule is amended.

- Remove the broad exemption for agricultural operations at 1.3.3 or justify why it is appropriate to treat sources at agricultural operations differently than identical sources at non agricultural operations. 7. EP A Action – EPA staff recommends full disapproval of the April 17, 2008 submittal of MBUAPCD Rule 400 pursuant to CAA § 110(k) because the submittal would only weaken the SI P and the State has not shown that the submittal complies with the CAA in light of th e deficiency

described above. There are no CAA § 110(c) FI P or § 110(m) sanction implications of this action since this is not a required submittal. 8. Attachments a. MBUAPCD Rule 400 - Visible Emissions , adopted December 15, 2004 . b. “ Staff Report ; Proposed Revisions to Rule 400 (Visible Emissions)” , MBUAPCD, December 15, 2004 . c . “State Implementation Plans: Policy Regarding Excess Emiss ions During Malfunctions, Startup, and Shutdown”, USEPA Memorandum, September 20, 19 99 .