OCEAN MIST FARMS - Executive Summary |
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EXECUTIVE SUMMARY 1. PREVENTION AND RESPONSE Ocean Mist Farms (OMF) operates a shipping and cooling facility in Castroville, CA. in addition to facilities in other counties. Risk prevention and emergency response procedures are in place at all OMF facilities. The same management and maintenance personnel are responsible at all facilities for maintaining the ammonia refrigeration equipment to prevent releases, and for responding to an emergency. The Emergency Response Plan lists the responsible personnel and the policies for responding to an accident involving the regulated substance. The cold storage ammonia refrigeration system has safeties to detect both ammonia releases and unsafe operating conditions. These are tied into an alarm system that is monitored 24 hours per day. There are also portable refrigeration unit's onsite which have no detection since the units are outdoors. Operators are present to monitor the operating conditions of these units when they are running. There is a list of responders experienced with ammonia refrigeration that would respond and determine specific responses for any incident. Safeties and detection equipment are tested and maintained by experienced maintenance personnel as spelled out in the SOPs and the maintenance program. 2. STATIONARY SOURCE AND SUBSTANCE DESCRIPTION At the Castroville facility, ammonia refrigeration systems are used for cold storage, produce precooling, and ice generation. The cold storage refrigeration system is a fixed system attached to the building. The portable refrigeration equipment is trailer mounted and used for ice generation and for precooling of produce. The trailers are outdoors and can be moved from one facility to another. The refrigeration systems were started in April 1996 and designed as per current applicable building and safety codes. The total charge refrigeration change for all systems is 40,000 LBS. 3. RELEASE SCENARIOS Both a worse case and an alternate case rele ase scenario were modeled for this RMP utilizing a computer-modeling program. The worse case was a release of the entire ammonia charge of the largest system in 10 minutes with ambient conditions as required by EPA regulations. The alternate was a release for 25 minutes averaging approximately 100 LBS/minute. This is a more probable release due to items such as rotating seals, pressure relief valves, leaks in piping, charging system or draining oil. The modeling software used was "A Real Locations of Hazardous Atmospheres" (ALOHA) from the National Safety Council in cooperation with the EPA. Both scenarios were considered releases in a rural setting. Release plumes were plotted on maps, which showed the location of populations, schools, public areas, and acute care facilities if effected by the release. The mapping software utilized was "Mapping Application for Response and Planning of Local Operational Tasks" (MARPLOT) also from the National Security Council. Effected populati ons were estimated using "Land View III," a computer census modeling program from the Bureau of Census that calculates census data of areas defined on MARPLOT generated maps. Offsite consequences were analyzed at 200 PPM level of concern for the two above release scenarios. Results show the worse case scenario having a potential endpoint of 2.1 miles. If the area were encircled with the 2.1-mile endpoint distance as the radius, the total area population would be approximately 6,000. This area contains one primary school, one middle school, one high school, and two day care centers. There are four public parks and part of a state highway in the potentially effected area. The alternate scenario has considerably less offsite consequence with an endpoint of 2,289 feet at 200 PPM. One day care center, close businesses, and some residences could be affected depending on wind direction. There are various measures in place to limit the endpoint distances of a release. One is an ammon ia monitoring system providing early detection for the cold storage system. Relief valves are tied into diffuser water tanks rather than piped to ambient. The cold storage system has an emergency control box for manual pressure release, which is tied into a diffuser tank. Preventive maintenance and safety inspections are used to insure equipment and piping is maintained and operating in a safe manner. 4. GENERAL RELEASE PREVENTION PROGRAM OMF maintains a release prevention program to eliminate or minimize releases. The program includes regular inspections, monitoring equipment, logging conditions, scheduled maintenance, and operator training. A program to document releases and analyze ways to prevent a similar future releases is in place. A Risk Management Program, which includes accident prevention procedures for the ammonia refrigeration system, is maintained on-site along with this RMP. The ammonia refrigeration system has specific safety procedures to prevent a release. Operators and mechanics are trained for safe operation and maintenance of the refrigeration system. They are also trained in emergency response procedures in the event of an ammonia release. There are emergency shut off switches outside the equipment room for the cold storage system that would shut down both the system and the ammonia flow. The cold storage refrigeration system is monitored by an alarm and detection system for unsafe ammonia concentration levels and for operating conditions outside of safety set points. Monitoring is 24 hours per day. An emergency control box that is tied into a water diffuser tank allows system pressure to be relieved without releasing to ambient. Vessel pressure relief valves are also tied into this diffuser tank. 5. FIVE YEAR ACCIDENT HISTORY There have been no accidents at this facility. 6. EMERGENCY RESPONSE PROGRAM In event of a release, certain personnel are designated to determine the potential hazard and coordinate response procedure s. The emergency coordinator is responsible for contacting emergency response agencies, schools, daycare centers, and acute care facilities that may be effected by the release. The coordinator will also be responsible for evacuation of employees if necessary, and for coordination with community emergency responders if off-site evacuations are required. 7. PLANNED CHANGES TO IMPROVE SAFETY The ammonia refrigeration system is relatively new and built to meet the latest building, mechanical, and safety codes. The same trained operators and mechanics that now operate and maintain similar facilities will operate and maintain this system. However, a more intensive and formalized safety-training program will be implemented by May 1, 1999. Specific recommendations resulting from the PHA are listed in the hard copy of the Risk Management Program maintained at the facility. They are all minor items. |