Sumas Cogeneration L.P. - Executive Summary |
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EXECUTIVE SUMMARY PER 40CFR 68.155(a) ACCIDENTAL RELEASE PREVENTION PROGRAM 1. Accidental Release Prevention and Emergency Response The Sumas Cogeneration LP facility in Sumas, Washington handles anhydrous ammonia which is considered hazardous by EPA. The toxicity of ammonia at high concentrations make it necessary to observe certain safety precautions to prevent unnecessary human exposure, and to reduce the threat to the personal health of our employees as well as nearby members of the community. It is our policy to adhere to all applicable Federal and state rules and regulations. Safety depends upon the manner in which we handle ammonia, the safety devices inherent in the design of the facility, combined with the safe handling procedures that we use and the training of our personnel. Sumas' emergency response program is designed to effectively respond to an accidental release of ammonia. The emergency response plan includes procedures for notification of the Local Emergenc y Planning Commission (LEPC), the State Emergency Management Division, and the National Response Center. 2. The Stationary Source and Regulated Substances The primary purpose of the Sumas cogeneration facility is to produce electric power from combustion of natural gas. Anhydrous ammonia is used at the facility to reduce the formation of oxides of nitrogen (N0x) produced during combustion. Anhydrous ammonia is received by truck and stored as a liquid under pressure in a single storage tank. The ammonia is transported by pipeline, from storage and injected into the combustion system where it reacts with the natural gas combustion products to minimize N0x formation. Access to the site is restricted to authorized facility employees, authorized management personnel and authorized contractors. The regulated substance handled at this facility is anhydrous ammonia. The maximum amount of ammonia that can be stored at this plant is 52,000 pounds. 3. The Worst-Case and Alternative Rele ase Scenarios Worst-Case Scenario 7 The worst-case release would be a catastrophic failure of the anhydrous ammonia storage tank when filled to capacity. This worst-case scenario would release 52,000 pounds of ammonia. It is assumed that the entire contents are released as vapor within 10 minutes of the failure. 7 The distance to the end-point concentration of 0.14 mg/l ammonia for this worst-case scenario is 4.0 miles. It should be noted that the worst case is not chemically or thermodynamically possible without a large infusion of heat into the ammonia. Approximately 60% of the ammonia would remain in a liquid state and evaporate slowly over a period of days if an external source of heat was not added to increase the evaporation rate. If the worst case assumption that 100% of the ammonia evaporates in 10 minutes as required by EPA were adjusted to reflect the actual chemical and thermodynamic properties of ammonia, the downwind impact distance would be substantially less than 4 miles. Alternative Scenario 7 The more realistic alternative-case release would be the failure of a 2-inch diameter anhydrous ammonia fill pipeline. This scenario would result in a total release of 20 pounds of ammonia. 7 The distance to the end-point concentration of 0.14 mg/l ammonia for this alternative release scenario is 0.1 miles. 4. Accidental Release Prevention Program The Sumas cogeneration facility complies with EPA's Accidental Release Prevention Rule and with all applicable state codes and regulations. This facility was designed and constructed in accordance with all applicable ammonia storage and handling codes. All employees involved with the operation or maintenance of the anhydrous ammonia system are thoroughly trained using Sumas' documented training program. 5. Five-Year Accident History No accidental releases of ammonia causing on-site or off-site injury or damage have occurred during the life of this facility. 6. Emergency Response Program Sumas' emergen cy response program is based upon an accidental release of ammonia. We have discussed this program with the Whatcom County Local Emergency Planning Committee and the Sumas Fire Department. |