ARCHIVED REPORTS LEC APPLICATION FOR CERTIFICATION

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5.1C:EVALUATION OF BEST AVAILABLE CONTROL TECHNOLOGY The ammonia emissions resulting from the use of SCR may have another environmental impact through their potential to form secondary particulate matter such as ammonium nitrate. Because of the complex nature of the chemical reactions and dynamics involved in the formation of secondary particulates,it is difficult to estimate the amount of secondary particulate matter that will be formed from the emission of a given amount of ammonia. However, the SJVAPCD has stated that because of high background levels of ammonia,the formation of ammonium nitrate and ammonium sulfate in the San Joaquin Valley air basin is limited by the formation of nitrates and sulfates and not driven by the amount of ammonia in the atmosphere. Therefore, ammonia emissions from the proposed SCR system are not expected to contribute significantly to the formation of secondary particulate matter within the SJVAPCD. A second potential environmental impact that may result from the use of SCR involves the storage and transport of anhydrous ammonia. Although ammonia is toxic if swallowed or inhaled and can irritate or burn the skin,eyes,nose, or throat,it is a commonly used material that is typically handled safely and without incident and is already being stored and used at the existing STIG#2 plant. As discussed in Section 2.0, the project will utilize the existing ammonia delivery system,which consists of an ammonia storage tank,spill containment basin, and refilling station with a spill containment basin and sump—new ammonia storage facilities will not be constructed as part of the proposed project. NCPA is already required to maintain a Risk Management Plan(RMP) and to implement a Risk Management Program to prevent accidental releases of ammonia. The RMP will be updated to include use of ammonia at the LEC (see Section 5.5 of the AFC). The RMP provides information on the hazards of the substance handled at the facility and the programs in place to prevent and respond to accidental releases. The accident prevention and emergency response requirements reflect existing safety regulations and sound industry safety codes and standards. Thus,the potential environmental impact due to anhydrous ammonia use at the LEC is minimal and does not justify the elimination of SCR as a control alternative. Regeneration of the EMx catalyst is accomplished by passing hydrogen gas over an isolated catalyst module. The hydrogen gas is generated by reforming steam, so additional steam would be required beyond that for which the project is designed. This would require an increase in the size of the auxiliary boiler as well as an increase in expected boiler operation and emissions. 5.1C.1.1.1.2 Achieved in Practice Evaluation While there are no formal"achieved in practice' criteria in the SJVAPCD,the SCAQMD has established formal criteria for determining when emission control technologies should be considered achieved in practice (AIP) for the purposes of BACT determinations. The criteria include the elements outlined below. • Commercial Availability: At least one vendor must offer this equipment for regular or full-scale operation in the United States. A performance warranty or guarantee must be available with the purchase of the control technology, as well as parts and service. • Reliability: All control technologies must have been installed and operated reliably for at least six months. If the operator did not require the basic equipment to operate daily, then the equipment must have at least 183 cumulative days of operation. During this period,the basic equipment must have operated (1) at a minimum of 50% design SAC/371322/082330016(LEC_5.1 C_APPEN D IKI)OC) 5.1 C 4