ARCHIVED REPORTS LEC APPLICATION FOR CERTIFICATION

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5.5 HAZARDOUS MATERIALS HANDLING and non-flammable. Ammonia gas can be toxic to humans at sufficient concentrations. Potential toxic effects of ammonia and acceptable exposure levels are summarized in Table 5.5-4. The odor threshold of ammonia is about 5 ppm,and minor irritation of the nose and throat will occur at 30 to 50 ppm. Ammonia concentrations greater than 140 ppm will cause detectable effects on lung function even for short-term exposures (0.5 to 2 hours). At higher concentrations of 700 to 1,700 ppm, ammonia gas will cause severe effects; death occurs at concentrations of 2,500 to 6,000 ppm (Smyth,1956). The hazard to facility workers will be mitigated by facility safety equipment,hazardous materials training, and emergency response planning(see Section 5.16,Worker Health and Safety). In a catastrophic accident, toxic ammonia gas could migrate off site and affect the health of humans at locations surrounding the facility (see below,Section 5.5.2.4.2). Facility design will minimize the potential for harm to humans located off site. 5.5.2.5 Fire and Explosion Hazards Table 5.5-3 describes the flammability for the hazardous materials that will be on site. Article 80 of the California Fire Code requires all hazardous materials storage areas to be equipped with a fire extinguishing system and also requires ventilation for all enclosed hazardous material storage areas. Anhydrous ammonia,which constitutes the largest quantity of hazardous materials stored onsite,is a colorless,non-flammable liquefied gas. Under normal storage conditions, ammonia would not evaporate to the atmosphere because it is contained in a sealed tank that maintains the ammonia in a state that precludes evaporation. In the unlikely event that a release were to occur, ammonia could evaporate directly to the atmosphere. Ammonia vapor is combustible only within a narrow range of concentrations in air. It will ignite at a temperature of 1204°F within vapor concentration limits between 15% and 28% and the presence of a strong ignition source. Outside conditions that would support these vapor concentrations are rare.The evaporation rate of ammonia is similar to water,which is sufficiently low that the lower explosive limit of 15 percent (or 15,000 ppm) will not be reached. The plant machinery lubrication oil is flammable. In accordance with Article 80 of the California Fire Code,the storage area for the lubrication oil would be equipped with a fire extinguishing system and the lubrication oil would be handled in accordance with an HMBP approved by the San Joaquin County Environmental Health Department,the San Joaquin County Office of Emergency Services, and the CEC.With proper storage and handling of flammable materials in accordance with the California Fire Code and the site-specific HMBP,the risk of fire and explosion at the generating facility would be minimal. The LEC will require construction of a 2.5-mile natural gas pipeline which will interconnect to PG&E's distribution pipeline#108. Natural gas is composed mostly of methane,but also may contain ethane,propane,nitrogen,butane, isobutene, and isopentane. It is colorless, odorless, tasteless,and is lighter than air. Methane is flammable when mixed in air at concentrations of 5 to 14 percent,which is also the detonation range. Natural gas,therefore, poses a risk of fire and explosion if an accidental release were to occur. However,the risk of SACI3713221082330015(LEC_5.5_HAZMAT.DOC) 5.5-19