Westward Seafoods, Inc. - Executive Summary |
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This Risk Management Plan (RMP) is submitted to the United States Environmental Protection Agency (EPA) to meet the requirements of Section 112(r) of the Clean Air Act Amendments of 1990, codified in the Code of Federal Regulation Title 40 Part 68. Stationary source and chemical of concern Westward Seafoods is located on Unalaska Island in Dutch Harbor, Alaska. The facility is staffed year-round and also employs a large seasonal workforce during the spring and summer months. The plant produces fresh and frozen seafood products, using Anhydrous Ammonia in a closed system as a refrigerant in freezers and cold storage. Ammonia is the safest refrigerant available and has excellent warning properties; it is extremely pungent at levels far below dangerous concentrations. The maximum inventory of ammonia in the plant system is 80,000 pounds. In calculating worst-case and alternative scenarios, efforts were made in all cases to overestimate rather than underestimate the effects of a r elease. The Westward Seafoods facility is a modern plant that has been operating safely since it was built in 1989. Worst-case Scenario A worst case scenario is required to be documented in the RMP. Failure of the largest vessel in the system, the High Pressure Receiver (HPR) when filled to capacity would release 31,500 pounds of ammonia. The HPR is located in the Compressor Room. Based on the requirements of the RMP rule, it is assumed that the HPR fails catastrophically, releasing its entire contents over a 10-minute period. To obtain the most conservative assumption, is assumed that the building does not mitigate the rate of release, but the ammonia exits to the outdoors via doors and ventilation fans in the Compressor Room walls. The release is modeled using RMP*Comp(tm) software. Alternative Release Scenario The alternative release scenario for the ammonia refrigeration process is based on a potential hazard identified during the Process Hazard Analysis conducted du ring documentation of the facility prevention plan. In this scenario, a plate freezer hose fails. The failure causes liquid ammonia to release to atmosphere. To obtain the most conservative assumption, no mitigation is considered in the scenario calculations. The release is evaluated according to the procedures documented in Chapter 4 of the EPA's "Risk Management Program Guidance for Ammonia Refrigeration" (EPA GAR). Release Prevention Program Westward Seafoods has a prevention program in place to comply with the requirements of the OSHA Process Safety Management (PSM) program, which is designed to prevent accidental releases of ammonia. The PSM program addresses all required elements including employee participation, process safety information and system drawings, operating procedures, hot work permits, management of change, mechanical integrity, training, pre-startup review, compliance audits, process hazard analysis, contractor safety, incident investigation and emergency response. The system has many safety features built in including high and low level controls and alarms, pressure relief valves, automatic and manually controlled valves and shutoffs, and check valves. Plant personnel responsible for the system have had extensive training including courses published by the Refrigeration Engineers and Technicians Association (RETA). Five Year Accident History Per the requirements of 40 CFR 68.42, facilities must include a five-year accident history for all accidental releases from covered processes that resulted in deaths, injuries, or significant property damage on site or known offsite deaths, injuries, evacuations, sheltering in place, property damage, or environmental damage. There have been no such accidents at this facility in the past five years. Emergency Response Program Westward Seafoods maintains a written emergency action plan as part of the PSM plan to facilitate safe response to accidental ammonia releases. The plan identifies personnel designated and trained to conduct the necessary duties during a response. Responsibilities include notification of and communication with local responders and authorities, coordinating and conducting responses, as well as maintenance of emergency equipment and trained personnel. The facility has coordinated its emergency response plan with local authorities and responders and conducts drills periodically to practice responses. |