Del Mesa Farms Porterville - Executive Summary |
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DEL MESA FARMS PORTERVILLE PLANT RISK MANAGEMENT PROGRAM AND PROCESS SAFETY MANAGEMENT PROGRAM Anhydrous Ammonia Refrigeration System August 1999 EXECUTIVE SUMMARY Del Mesa Farms Porterville (Del Mesa Farms) prepared a Chemical Risk Management Program and Process Safety Management Program (RMP/PSM) in general accordance with state and federal regulations. The state risk management regulations, also referred to as the California Accidental Release Prevention (CalARP) program, are codified in California Code of Regulations (CCR), Title 19, Section 2735.1, et. Seq. The Federal Environmental Protection Agency (EPA) also regulates facilities with certain toxic and flammable substances. The federal regulations are codified in Title 40 of the Code of Federal Regulations (CFR), Part 68. Finally, both CalOSHA and Federal OSHA regulate facilities with certain acutely hazardous materials under the Process Safety Management regulations, as defined in CCR Title 8 Section 5189 and CFR Titl e 29 Part 1910 Section 119, respectively. Del Mesa Farms prepared the RMP/PSM to satisfy regulatory requirements and to demonstrate a commitment to evaluate and improve anhydrous ammonia handling systems and practices at the facility. Many state-of-the-art safety features have been incorporated into the ammonia refrigeration system at the facility as part of the original system construction. In the unlikely event that a chemical release does occur at the facility, Del Mesa Farms personnel are trained in the appropriate response measures, relying on backup support services provided by the local fire department and/or hazardous materials response team. Del Mesa Farms will continue to improve ammonia-handling safety through the implementation of the prevention program elements of the RMP/PSM. Del Mesa Farms Porterville is located at 770 Plano Street, Porterville, California, approximately 1.5 miles east of Highway 65. The surrounding area consists of residential development and indus trial and commercial businesses. The site is bordered by Plano Street to the west, Henderson Avenue to the north, and other industrial business to the south and east. The facility is located on the eastern edge of Porterville, thus the area surrounding the facilities consists of a combination of industrial transitioning to rural and sparsely populated rural residential. The facility was constructed as a manufacturing site for diapers and related products. Del Mesa Farms purchased the facility in 1998 and is currently converting the facility for processing poultry products. The new poultry processing equipment will come on line in phases and the initial equipment (which includes the refrigeration system) is expected to be ready for startup during the third quarter of 1999. Production equipment will start up in subsequent months after the storage and processing areas have been cooled and prepared to handle the poultry meat/products. Operations at the facility will consist of processin g, packaging, storage, and shipment of poultry and deli meat products. The facility is surrounded by chain-link fencing and has a secured entrance that will be staffed by security personnel 24-hours-per-day, 365-days-per-year. Anhydrous ammonia will be used in a refrigeration system at the facility. The ammonia refrigeration system, which is designed as a closed system, will contain approximately 18,000 pounds of anhydrous ammonia. The system will provide cooling for production areas, raw materials storage, product storage and chilled water (brine solutions). A central computer system will monitor and control the refrigeration system. The desired temperatures will be maintained by controlling the flow of ammonia with manually and electrically operated valves, float switches, circulating pumps, and compressor controls. The RMP regulations require a review of the five-year accident history at the regulated facility. Because this is a new facility (i.e., new refrigeration system and first introduction of ammonia at the site) there is the no history of accidental releases. The RMP regulations require facilities to identify and evaluate chemical release scenarios resulting from potential failures of the chemical handling systems covered by the RMP. Program 3 requirements of the RMP apply to the Del Mesa Farms facility due to the quantity of ammonia expected to be used. Program 3 facilities are required to evaluate a worst-case release scenario (release parameters are defined by the regulations) and an alternative release scenario. The regulations define a worst-case release scenario as "the greatest amount held in a single vesselreleased as a gas over 10 minutes." An alternative release scenario is identified as a release that is more likely to occur at the facility. The largest ammonia vessel at Del Mesa Farms, the high-pressure receiver, has a capacity of 18,000 pounds of ammonia at 80% liquid level, the safe fill level for the vessel. Therefore, the w orst-case release scenario for the facility is a release of 18,000 pounds of ammonia in 10 minutes. Catastrophic failure of the high-pressure receiver would be required for this scenario to occur. As required by the RMP regulations, pessimistic atmospheric conditions, very conservative chemical dispersion characteristics, and a toxic endpoint of 200 parts per million (ppm) ammonia vapor were assumed. The SLAB Model was used for modeling the worst-case release scenario. SLAB was first developed by Lawrence Livermore National Laboratory under contract with the U.S. Department of Energy. SLAB has been revised and updated by the USAF Engineering and Services Center and the American Petroleum Institute. SLAB is commonly used to simulate the atmospheric dispersion of denser-than-air releases. Del Mesa Farms used the alternative release scenario described in the Environmental Protection Agency's (EPA) Model Risk Management Program and Plan for Ammonia Refrigeration, November 1998. The release scenario is described as a <-inch effective diameter orifice leaking liquid ammonia and resulting in an airborne release, representative of a pipe connection leak, pump seal failure, or a gasket failure. The evaluation used a release rate of 94 pounds/minute and average weather conditions. The SLAB Model was used also for modeling the alternative release scenario. The RMP/PSM regulations require a review of the accidental release prevention program and chemical specific prevention steps used by the facility. Del Mesa Farms has incorporated many safety features in the ammonia refrigeration system to prevent system failures and to mitigate potential releases. The predominant safety concern with closed-loop ammonia systems is an inadvertent buildup of pressure exceeding pressure ratings or capacities of equipment due to ammonia expansion. The Del Mesa Farms ammonia system is continuously monitored by automated control systems that shut down components if deviations from norma l operating conditions occur. The major pressure vessels in the system are connected to a diffusion panel. Ammonia from the vessels can be mixed with water (neutralized) in a diffusion tank and discharged to the sewer system to prevent over-pressurization of the vessels. Further, all pressure vessels in the system are equipped with pressure relief valves (also connected to the diffusion tank). Other safety features at the facility include: 7 emergency shutdown systems 7 component specific safety shutdowns 7 safeties will be tested annually 7 pressure relief valves on all vessels, compressors, and several other areas in the system where trapped ammonia could build pressure 7 pressure relief valves are vented to a common header connected to the water diffusion system, designed to mix vented ammonia with water for safe disposal to the municipal sewer 7 vessels are connected to a fire diffusion panel, which allows manual routing of ammonia to the water diffusion system in the event o f a fire 7 ammonia pipes, valves and components are labeled 7 pressure relief valves will be replaced at least every five years 7 a fire sprinkler and alarm system is installed in the plant 7 a central computer system monitors the refrigeration system and alarms when safety set-points are exceeded 7 ammonia leak detection system which provides early warning alarms for the process areas and can automatically shutdown the refrigeration system if engine room leaks are detected 7 operators will receive ongoing training in operations, maintenance and emergency response In addition to the physical features of the ammonia refrigeration system at the facility, Del Mesa Farms will be implementing extensive administrative controls to maintain safe operation of the system. Administrative controls include, but are not limited to formal training programs for system operators and mechanics, emergency training, a hot work permit program, a lockout/tagout program, a contractor safety program, incide nt investigation program, mechanical integrity program, management of change program, pre start-up safety review program, and a RMP/PSM auditing and inspection program. Written standard operating procedures (SOPs) are being prepared for the ammonia system at the facility. The SOPs provide a basis for site specific operator training and a ready reference for operating and trouble-shooting the systems. Del Mesa Farms is committed to maintaining the mechanical integrity of the ammonia refrigeration system. A preventive maintenance system has been developed to manage the maintenance of the refrigeration system. Preventive maintenance at the facility will include daily, weekly, and periodic inspection; calibration; testing; and overhaul of ammonia system equipment. The preventative maintenance system will be used to track equipment performance and to monitor the frequency of repairs and deviations from normal operating parameters. Changes to improve safety at the facility will be ong oing and part of Del Mesa Farms commitment to continuous improvement. A process hazard analysis was recently conducted on the ammonia refrigeration system to identify further safety improvements. Many of the mitigation measures suggested by the process hazard analysis team have already been implemented. Other recommendations are expected to be complete prior to startup. Del Mesa Farms is committed to respond to all suggested mitigation measures promptly and is establishing schedules of proposed actions for the ongoing improvement of the systems. Management responses and support will be consistent with Del Mesa Farms' commitment to safe and environmentally responsible operations. Del Mesa Farms recognizes that the RMP/PSM is a continuous process for evaluating, monitoring, and improving anhydrous ammonia handling operations at its facility. As such, this document and related attachments and program elements will evolve as Foster Farm continues their ongoing focus and dedication of r isk minimization and safety improvement for their employees and surrounding community. Del Mesa Farms will submit revised information if a change occurs that is considered significant and requires resubmission under the regulations. However, minor improvements / modifications to the RMP/PSM, related attachments, and program elements will be incorporated consistent with Del Mesa Farms' internal review practices, and Del Mesa Farms will maintain the most current versions on site. Thus, the most current version RMP/PSM, related documents, and elements maintained on site may vary slightly from the information in submittals made to EPA and other regulatory agencies. |