Milan Pork Processing Facility - Executive Summary |
|
EXECUTIVE SUMMARY Premium Standard Farms operates a pork processing facility near the northeast corner of Milan, Missouri. The facility is located at the northwest corner of the intersection of Highway 5 and Highway 6, and has been at this location for approximately 6 years. The nature of our business involves swine slaughter and processing of pork products for commercial distribution. The Milan pork processing facility has very few hazardous or toxic materials on site. Our facility's refrigeration system uses approximately 108,000 pounds of ammonia as refrigerant. The horizontal recirculator vessels V3 and V4, located outside the northwest wall of the main facility structure, hold the greatest amount of ammonia. One of these recirculators can hold as much as 28,300 pounds of ammonia, based on maximum high level controls in the vessels. Premium Standard Farms is committed to maintaining our ammonia equipment in safe condition, and to providing our personnel with training in saf e operating practices. This facility has never had an accidental release of propane from our facility which resulted in adverse health effects to the public or to our employees, or to damage to property. WORST CASE SCENARIO The maximum on-site inventory of ammonia at the Milan pork processing facility is approximately 108,000 pounds, constantly circulating through the refrigeration system's 6 vessels, compressors, condensers, pumps and piping. For the worst case scenario analysis, the contents of the vessel capable of containing the greatest quantity of ammonia must be assumed to be catastrophically released, if the resulting toxic vapor cloud results in the farthest possible endpoint determination for the facility. Vessel V3, the Intermediate Temperature Recirculator, contains the greatest quantity of ammonia, because of its size and pressure. This vessel could contain as much as 28,300 pounds of ammonia. The EPA requires that this maximum quantity be imagined released in a 10 minute period in order to calculate the worst case scenario. This results in a release rate of 2,830 pounds/minute (lbs/min). EPA has calculated the endpoints and provided results for ammonia as a function of rate of material released. For the Milan pork processing facility's worst case scenario described above, the endpoint is 2.0 miles from the recirculator vessel. ALTERNATE SCENARIO The alternative release scenario should reflect an incident that has occurred, or potentially could occur, at the PSF's Milan facility. In addition, EPA guidance documents state that the scenario should: 7 Be more likely to occur than the wor st case scenario, and, 7 Result in a distance to the endpoint exceeding the distance to the facility boundary, unless no such scenario exists. The alternative scenario selected for PSF's Milan facility involves a leak in the piping used to transfer ammonia from the High Temperature Recirculation Vessel (V2) to the Intermediate Temperature Recirculator Vessel (V3). The pump seal or a flange gasket ruptures while the system is unattended. This scenario is more likely to occur than the worst case scenario, and compared to other realistic alternative scenarios, would be relatively likely to result in the maximum (greatest) distance to endpoint. In this scenario, a shutoff valve would need to be closed manually in order to terminate the release of ammonia from a rupture in the piping. An EPA guidance document states that in a database of ammonia refrigeration system accidental releases the agency has compiled, this type of failure represents a large number of the incidents which were r eported. This type of failure typically results in an effective hole area of < to = square. In order to use the EPA guidance document modeling technique, a hole size must be assumed. Using the upper end of the range given by the Agency, = square inch, allows a conservatively high release rate to be calculated for the alternative scenario. The line pressure between V2 and V3 is 75 psig. Using the assumed hole area and this pressure results in a release rate of approximately 880 lbs/min. Using this value, and corresponding endpoint estimates provided by the agency, results in a distance to endpoint of 0.2 miles. The endpoint estimates provided by the EPA are specifically stated by the Agency to apply to releases of any duration. GENERAL ACCIDENTAL RELEASE PREVENTION PROGRAM Our Plant Vice President of Operations, our Plant Manager, and all our employees are dedicated to maintaining our ammonia refrigerant system in a safe manner, and using it safely should we ever be required to do so. We have clear lines of authority and responsibility with respect to all aspects of our release prevention program, leading directly to the Plant Vice President of Operations. We maintain current safety information on ammonia and our ammonia refrigeration equipment, and review any potential hazards that may be associated with the storage and potential use of ammonia at our facility. In addition, we train both our operating and maintenance personnel, in our procedures and safe practices. New employees are trained before being allowed to work alone, and periodic refresher training is provided to all employees. Any time significant changes occur in equipment or processes which could potentially impact the storage or use of ammonia, affected employees are retrained. We inspect and audit our facility, using both in house staff and trained professionals from outside our company. EMERGENCY RESPONSE Because ammonia is a toxic substance above EPA's CAA Risk Management Program threshold quantity, the PSF Milan pork processing facility is required to 1) develop an emergency response program including a written emergency response plan; or 2) coordinate response actions with the Milan, Missouri Fire Department. The Milan facility has developed a written emergency response plan. The plan designates incident commanders, an administrative assistant responsible for contacting outside agencies at the direction of the incident commander, two health professionals, and a 20 person emergency response/haz mat team. The facility has officially coordinated emergency response planning with the Sullivan County Local Emergency Planning Committee (LEPC). Included in the emergency response plan are a list of emergency response equipment locations, guidance on coordination with outside agencies, emergency phone numbers, and response team training requirements. |