



                                       
                 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
                            REGION IX AIR DIVISION




                          Technical Support Document 
                                      for
                              EPA's Rulemaking
                                    for the
                     California State Implementation Plan
                                       
                   El Dorado Air Quality Management District
                         Ozone Emergency Episode Plan




                              
                          Prepared by: Vanessa Graham
                         Reviewed by: Andrew Steckel 

                                   May 2016





RULE IDENTIFICATION - 
Agency
                        EL Dorado County Air Quality Management District (EDCAQMD)

SIP Approved Plan
None

Subject of this TSD
Ozone Emergency Episode Plan
Adopted  -  January 12, 2016 
Submitted  -  April 6, 2016

Completeness Finding
Determination of Completeness letter: April 21, 2016


BACKGROUND  -  Section 110(a) of Clean Air Act (CAA) requires each state to develop and submit to the EPA a plan that provides for the implementation, maintenance, and enforcement of the national ambient air quality standards (NAAQS). Section 110(a)(1) also requires that each state make a new State Implementation Plan (SIP) submission within 3 years after the promulgation of a new or revised primary or secondary NAAQS, for approval into the existing SIP to assure that the SIP meets the applicable requirements for the new or revised NAAQS. This type of SIP submission is commonly referred to as an "infrastructure SIP". 

To facilitate planning efforts, the state of California is divided into air quality control regions (AQCR). Each AQCR is assigned Priority I, II or III with respect to emergency episode classification, based on threshold levels specified in the Code of Federal Regulations (CFR) at 40 CFR Part 51, Subpart H. Priority I and II areas have specific emergency episode plan requirements designed to prevent ambient concentrations from reaching specified significant harm levels (SHL). Priority III areas have no emergency plan requirements. 

SUMMARY  -  AQCRs with ozone concentrations greater than 0.10 ppm must be classified Priority I. Review of EDCAQMD 2011-2014 air quality data revealed that EDCAQMD exceeded the 0.10 threshold on numerous occasions and recorded high one-hour ambient levels of 0.117 ppm. Therefore, EDCAQMD is considered a Priority I region and is required to prepare an ozone emergency episode plan. EDCAQMD's Ozone Emergency Plan, adopted on January 12, 2016, and submitted on April 6, 2016, was developed to fulfill the Infrastructure SIP emergency episode requirements as outlined in 40 CFR Part 51, Subpart H.

Each Priority I contingency plan must, at a minimum: 

 Specify two or more stages of episode criteria;
 Provide for public announcement whenever any episode stage has been determined to exist;
 Specify adequate emission control actions to be taken at each episode stage;
 Provide for prompt acquisition of forecasts of atmospheric stagnation conditions and forecast updates as frequently as they are issued by the National Weather Service;
 Provide for inspection of sources to ascertain compliance with applicable control action requirements;
 Provide communication procedures for transmitting status reports and orders as to emission control action to be taken during an episode stage, including contact with public officials, major emission sources, public health, safety, and emergency agencies and news media.

EVALUATION AND ACTION  -  EPA previously approved an analogous contingency plan for Placer County.  The El Dorado County Ozone Emergency Plan was largely modelled after the April 15, 2015 Placer County Air Pollution Control District Ozone Emergency Episode Plan.  The El Dorado plan was tailored to meet the specific ozone emissions generated within El Dorado County. Our evaluation of the El Dorado County Ozone Emergency Episode Plan finds the plan to be sufficiently clear and enforceable consistent with the general SIP enforceability requirements of CAA Section 110(a)(2). This plan is specifically intended to address CAA Section 110(a)(2)(G) requirements for an emergency episode plan or rule, which is summarized in the list of six items above and described in greater detail in 40 CFR part 51, subpart H (40 CFR 51.150 through 51.153). The six requirements above are fulfilled by requirements on pages seven thru eleven of the plan. There were no deficiencies found, and the addition of the Ozone Emergency Episode Plan strengthens the SIP. Nothing in the EDCAQMD plan, or EPA's approval of this plan, interferes with EPA's independent federal authority in CAA Section 303.

EPA RECOMMENDED ACTIONS  -  EPA staff recommends full approval of the plan as adopted on January 12, 2016 and submitted on April 6, 2016. 

ADDITIONAL RECOMMENDATIONS FOR THE NEXT RULE REVISION  -  EPA staff have no additional recommendations.

REFERENCES 

 California Infrastructure SIP prepared by ARB; Report Release December 23, 2013.
 California Infrastructure SIP Emergency Episode Planning Technical Support Document September 2014; prepared by USEPA, Region 9.
 40 CFR Part 51, Subpart H - Prevention of Air Pollution Emergency Episodes.
 USEPA Guidance on Infrastructure State Implementation Plan (SIP) Elements under Clean Air Act Sections 110(a)(1) and 110(a)(2), Stephen D. Page (EPA),  September 13, 2013. 
 Placer County Ozone Emergency Episode Plan (80 FR 76230, January 7, 2016)
 65 FR 53602, September 5, 2000 (EPA approval of SMAQMD Rule 701).
