Specialty Brands - Executive Summary |
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EXECUTIVE SUMMARY Accident Release Prevention Program and Emergency Response Policy It is the policy of the Specialty Brands Carthage, Missouri facility management to implement the requirements of this Risk Management Program (RMP) in accordance with the USEPA regulations under 40 CFR Part 68 and with the corresponding regulations under OSHA's Process Safety Management (PSM) program. The objective is to minimize the risk of a release of a hazardous material and if a release occurs, to minimize the potential impact to Specialty Brands employees, the public and the environment. This objective will be accomplished by utilizing general good operating procedures, providing appropriate training to all employees, and coordinating response activities, as necessary, with the local emergency response providers. This plan covers all Specialty Brands owned activities at this facility. Specialty Brands' management is committed to providing the resources necessary to implement this policy. Facili ty Description Specialty Brands, Inc. operates a food processing facility at this location. Specialty Brands is producer of breaded meat, breaded vegetables, and fried meat product. Support operations include cold storage, an analytical laboratory, and administrative offices. Figure 1-1 shows the site location and Figure 1-2 shows the facility layout. Two chemicals are utilized at the facility in sufficient quantities to be subject to the requirements of 40 CFR Part 68. These chemicals are ammonia and propane. Ammonia is used as a refrigerant throughout the facility and propane is used as a primary fuel supply for processing equipment. Worst-Case and Alternative-Release Scenarios RMP regulations require that each facility identify worst-case and alternative case release scenarios. EPA has defined a worst-case release as the release of the entire contents of the largest vessel that contains a regulated substance in a 10-minute period. This release rate is then evaluated using mod eling techniques and/or reference tables to define the distance to a specified endpoint (concentration or overpressure). The distance to the endpoint is affected by several factors including molecular weight, volatility, heat of combustion, and physical setting (urban or rural). The alternative release scenario must be one that is more likely to occur than the worst-case scenario and that reaches an endpoint offsite, unless no such scenario exists. The alternative release scenario is also evaluated to define the distance to the specified endpoint. Under 40 CFR 68 Subpart B '68.22(e), the RMP rule identifies surface roughness as a parameter to be used in the hazard assessment to determine the physical setting of the site, urban or rural. "Urban means there are many obstacles in the immediate area; obstacles include buildings or trees. Rural means there are no buildings in the immediate area and the terrain is generally flat and unobstructed." Due to the presence of trees, hills, and /or other structures in the immediate vicinity of the Carthage, Missouri facility, an urban dispersion environment was assumed. Ammonia The data provided in the document "Model Risk Management Program and Plan for Ammonia Refrigeration" (May 1996) was used to estimate the toxic endpoint distance for the worst-case and alternative ammonia release scenarios. The EPA's "RMP Off-site Consequence Analysis Guidance" (May 1996) was not used to determine the toxic endpoint since it classifies ammonia as a neutrally buoyant gas. Since the worst-case ammonia release would involve liquid and would come from a pressurized system containing liquid, the released gas should be classified as a dense gas (a result of evaporative cooling). The ammonia refrigeration document provides calculated endpoint distances for typical meteorological conditions. The worst-case release scenario for an anhydrous ammonia release included a release of all the contents of the high-pressure receiver in a 10-minute per iod (per EPA guidelines). This release translates to a release of 4,500 pounds of ammonia in 10 minutes or 450 lbs/min. Other assumptions included in the worst-case assessment are: the ammonia is a liquefied gas; the low pressure accumulator is not diked; the release does not take place indoors; the nearfield dispersion environment is characterized as rural; 10-minute averaging period; the windspeed is 1.5 meters/sec and the atmospheric stability is classified as F (stable). The results of the worst-case assessment for ammonia show that the plume must travel 0.80 miles (1.29 kilometers) before dispersing to the endpoint concentration of 201 ppm. Figure 1-3 details the worst-case release zone. The selected alternative-release scenario for the ammonia systems is a release from a relief valve due to overpressure of a compressor unit. The largest relief valve in the system was used in this scenario. The largest relief valve has a relief rate of 57.6 pounds of air per minute. As a ma tter of convention, the specified release rate of any relief valve is always in pounds of air per minute. The release rate of 57.6 pounds of air per minute correlates to a release rate of 41.3 pounds of ammonia vapor per minute. This release rate was applied to a release from the ammonia header on top of the building located on the condenser. The ammonia refrigeration document provides calculated endpoint distances for typical meteorological conditions (3 m/s wind speed, D atmospheric stability, and 50% relative humidity). It has been determined, through a review of Specialty Brands operational history, that the total release would likely be 500 pounds of ammonia. Based on the release rate of 41.3 lbs/min, the duration for a 500-pound release is 12 minutes. Other assumptions include that no active or passive mitigation measures are currently in place and an urban dispersion environment in the nearfield. The results of the alternative-release scenario for an ammonia release indica tes that the endpoint concentration of 201 ppm is reached at 0.06 mile (96.5 meters) from the release point. Figure 1-4 details the alternative-case release zone for ammonia and propane. Propane The worst-case release scenario for propane is defined as a release of all the contents of the propane storage tank (58,000 pounds). For the worst-case release of propane the release rate is not considered. The total quantity of the propane is assumed to form a vapor cloud. The entire contents of the cloud are assumed to be within the flammability limits, and the cloud is assumed to explode. For the worst-case analysis, 10% of the flammable vapor in the cloud is assumed to participate in the explosion (i.e., the yield factor is 0.10). Consequence algorithms were used to determine the endpoint at an overpressure level of one pound per square inch (psi). Other assumptions for the worst-case propane analysis include that the propane is a flammable gas; the storage vessel is not diked; no pas sive mitigation system is in place; the nearfield dispersion environment is characterized as rural; the wind speed is 1.5 meters/sec and the atmospheric stability is classified as F (stable). The results of the worst-case assessment for propane show that the 1-psi overpressure endpoint occurs at a distance of 0.31 miles (504 meters) from the release point. The selected alternative-release scenario for the propane system is a release resulting from a 50 feet 2-inch line rupture. To estimate the impact distance for this alternative-release scenario, a vapor cloud fire was assumed to occur. The distance to the Lower Flammability Limit (LFL) represents the maximum distance at which the radiant heat effects of a vapor cloud fire might have serious consequences. The LFL for propane is 36 mg/L (EPA guidance document). In accordance with USEPA guidance, the assumptions were that propane is a dense gas and an urban dispersion environment exists in the nearfield. According to the EPA guida nce document, the end point distance for release rate of 7,500 pounds per minute or less and a LFL between 35 and 40 mg/L is less than 0.06 miles (95 meters) from the release point. Figure 1-4 details the alternative-case release zone for the ammonia and propane. General Accidental Release Prevention Program and Chemical Specific Prevention Steps The Carthage, Missouri facility is governed by a set of OSHA and USEPA regulations that require planning and facility activities intended to prevent a release of hazardous material, or if a release inadvertently occurs, to minimize the consequences of a release to the employees of the facility, the public and to the environment. These regulations include: * 40 CFR Part 68, Accidental Release Prevention * 40 CFR Part 112, Spill Prevention, Control and Countermeasure * 40 CFR Part 264, Hazardous Waste Contingency Plan * 29 CFR Part 119, Process Safety Management * 40 CFR Part 302, Emergency Planning and Community Right-to-Know Act (EPCRA) The key concepts in Specialty Brands' release prevention program are employee participation, appropriate design and maintenance of equipment, and appropriate training of all employees. Specialty Brands has developed and documented these elements in their process safety management plan (PSM). The PSM plan is incorporated with this document by reference. Employee participation in the release prevention program is encouraged and supported by Specialty Brands management. Key personnel are responsible for conducting and implementing the findings from the Process Hazard Analysis (PHA) for the ammonia system and for conducting the process safety review for the propane system. Specialty Brands employees are also members of the facility emergency response team. Specialty Brands policy is to construct all new equipment, systems, and facilities to ensure the appropriate safety and release prevention systems are included from the beginning of each project. Specialty Brands maintains a program of maintenance activities to ensure that key systems are maintained appropriately to minimize the risk of a release. Specialty Brands is committed to providing appropriate training to all employees regarding safety procedures. Each new employee is provided comprehensive safety training during their initial orientation for the facility. In addition, Specialty Brands conducts regularly scheduled safety training for all employees each year. Additional training is provided to maintenance personnel for the systems they are responsible for. Members of Specialty Brands' emergency response team receive semiannual training to ensure that response actions are promptly and safely completed. Five Year Accident History Specialty Brands has not had any qualifying releases during the five years prior to program submittal from the Carthage, Missouri facility that has affected the public or the environment. Emergency Response Program Specialty Brands has personnel trained in ammonia emergency response at the facility 24 hours per day, seven days per week. These personnel receive annual training on emergency procedures and response techniques. Specialty Brands does not have emergency response capability on site to respond to a propane emergency. It is Specialty Brands' policy to contact off-site emergency responders for assistance in the event of an accidental release of propane. Specialty Brands' employees will attempt to extinguish small fires with fire extinguishers if they have been properly trained. Specialty Brands' employees, trained in the safe operation of the propane system, will close manual shutoff valves to terminate the flow of propane if the valves can be safely approached. For all other scenarios, Specialty Brands' employees will evacuate the area and allow off-site responders to respond to the propane emergency. Specialty Brands has met with the local fire department to review the propane system and to establish coordination and communication procedures. Planned C hanges to Improve Safety Specialty Brands completes a thorough review of the ammonia systems and the propane system each time a design change is implemented. Specialty Brands is committed to using these methods to identify and implement ways to improve the safety of these systems. |