J.R. Simplot Company - Executive Summary |
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Introduction J.R. Simplot Company's Grand Forks facility is part of the Simplot Food Group. The Grand Forks facility processes raw potatoes into frozen french fries and other frozen potato products. The Simplot Food Group turns out two billion pounds of frozen french fries and other frozen potato products per year at five facilities in the U.S. The frozen potato products are predominantly for the food service industry. Potato processing requires raw potatoes to be cleaned, peeled, cut to size, blanched, dried, fried, frozen, packaged and then placed in frozen storage. The cooling system uses anhydrous ammonia as the refrigerant. The U.S. Environmental Protection Agency (EPA) Risk Management Program (RMP) regulations 40 CFR Part 68, require facilities that have regulated substances above the listed threshold quantities to develop a formal Risk Management Program. EPA also requires these facilities to register and submit a Risk Management Plan to EPA using RMP*Submita by June 21 , 1999. The J.R. Simplot Grand Forks plant maintains quantities of anhydrous ammonia above the RMP threshold quantity of 10,000 pounds and as such is subject to the requirements of Program 3 in 40 CFR Part 68. The elements of the RMP are listed below: ? Hazard Assessment - Assess the potential impacts of worst-case and alternative release scenarios and compile a 5-year accident history. ? Prevention Program - Implement a comprehensive management program that affects a wide variety of operation, training, and maintenance activities. The requirements of the prevention program are identical to OSHA 1910.119 Process Safety Management Standard which the facility is also subject to. ? Emergency Response - Implement an emergency action program for the covered processes. ? Risk Management Plan - Register and submit an RMP plan that includes an executive summary, RMP data elements, results of the hazard assessment, and summarizes how all other requirements are met. The RMP is to be subm itted to EPA by June 21, 1999. The information presented in the next section is intended to describe the elements of J.R. Simplot Grand Forks facility's Risk Management Program. The format of the section corresponds to the executive summary data elements as dictated in 40 CFR Part 68 Executive Summary Section. EPA's RMP*Submit User's Manual was used as a guidance document for explanation of the regulation's intent of how the Executive Summary is to be structured. Executive Summary Data Elements According to EPA guidance the executive summary must include a brief descripton of the facilty's Risk Management Program. The following sections list each of the required executive summary data elements by rule citation. 68.155(a) Accidental Release and Emergency Response Policies J.R. Simplot company has operated the Grand Forks facility since 1981; however, the plant has been in operation since the late 1950's. The cooling system at the Grand Forks facility was remodeled in 1986. The safety features of the system continue to be re-evaluated and improved. The facility is currently supplementing its existing ammonia leak detection system with additional detection probes that will be integrated into the plant's computer operating system. This will allow the monitoring of the ammonia leak detectors on a plant wide basis. The facility has had a successful operating record. The safe operation of the Grand Forks facility is further illustrated by the recognition the facility received from the U.S. Department of Labor. U.S. Department of Labor, Certificate in recognition of outstanding contributions to the programs and objectives of the Occupational Safety and Health Administration, December 28, 1998. 68.155(b) Stationary Source and the Substance Handled Potato processing requires raw potatoes to be cleaned, peeled, cut to size, blanched, dried, fried, frozen, packaged and then placed in frozen storage. Anhydrous ammonia is the refrigerant in the facility' s cooling system. The facility operates four process lines each with cooling system components. In addition to the cooling systems associated with each process line, the facility operates large freezers for product freezing and storage. 68.155(c) Offsite Consequence Analysis One worst-case release scenario and one alternative release scenario was assessed for the refrigeration process. EPA defined the worst-case scenario as the release of the largest quantity of a regulated substance from a single vessel or process line that results in the greatest distance to an endpoint. This method was developed by EPA to ensure a common basis for comparison even though the EPA recognizes that the methodology uses assumptions that are not realistic and in some cases not physically possible. The alternative release rate is a release that is considered more reasonable or "more likely." Active mitigation measures can be used in determining the alternative release scenario while the worst-case scenario is only allowed consideration of passive mitigation measures. The toxic endpoint for ammonia has been defined by EPA to be 0.14 mg/L (200 ppm). This airborne concentration that is used as the toxic endpoint is the maximum airborne concentration below which it is believed that nearly all individuals can be exposed for up to one hour without experiencing or developing irreversible or other serious health effects. The distance to the toxic endpoint becomes a radius for a circle around the process containing the regulated substance. Residential population within the circle is required to be determined based on available census information. The population number is reported as part of the EPA submittal. This method greatly over estimates the population potentially exposed to a single ammonia release, because the ammonia plume would seek lowest elevations in the direction of the wind during a release. Since wind direction cannot be anticipated for an accidental release, EPA mandated the circle estimation method. Release scenarios and distances to toxic endpoints are discussed in more detail in the subsequent paragraphs. Worst-Case Release Scenario Worst-Case Release Scenario is determined in accordance with the requirements provided in 40 CFR 88.22 and 40 CFR 68.25(b & c). As described in USEPA 40 CFR Part 68.25(b) the worst-case release shall be the greater of the following: 1. The greatest amount held in a single vessel or 2. The greatest amount in a pipe. For the refrigeration system at the J.R. Simplot Grand Forks facility the worst-case release is that of a high-pressure receiver (maximum amount held in a single vessel) ruptures and its contents escape to the building in 10 minutes. According to EPA's guidance in the case of a vessel, the quantity does not include any liquid ammonia in pipework connected to the vessel and in any other vessel that can discharge directly into pipework connected to the vessel. However, the maximum amount of a mmonia that could be in the vessel at any one time, not just during normal operation is required to be considered. The facility has two high-pressure receivers with capacities of 14,500 pounds of ammonia each. Piping connects the receivers; however, per the EPA guidance only one of the vessels needs to be considered for purposes of determining the worst-case release quantity. In the event the high-pressure receiver would release its entire contents to the building in 10 minutes the release rate quantity would be 14,500 pounds which is equal to the maximum amount held in any single vessel at the facility. The rule allows the consideration of passive mitigation when estimating the worst-case release rate. Since the receiver is indoors and not directly adjacent to a door or window that may be open, the building provides some attenuation in the event of a release. The room structure facilitates the condensation of ammonia causing a rain-out effect. Only a portion of the total ammoni a quantity (Q) will become airborne while the remainder will collect in evaporating pools. EPA detailed a methodology for estimating a mitigated release rate in their guidance document entitled EPA's Risk Management Program Guidance for Ammonia Refrigeration. The methodology is presented below: To estimate the mitigated release rate, assume the following: 1. The amount of material airborne in the building four-tenths of the total inventory, or 0.4Q 2. The airborne material includes 0.2Q vapor and 0.2 Q liquid droplets. An attenuation factor for the worst case release scenario was taken from Exhibit 4-3 of the EPA guidance document Ten-minute Building Release Attenuation Factors for Prolonged Releases. Estimate o as follows: 1. Determine room volume, V, in cubic feet 2. Calculate o from room volume divided by the quantity of ammonia initially released as vapor, or o (ft3/lb) = V/(0.2Q) 3. Determine the active ventilation rate, Nv, in room volumes exchanged per hour (hr-1), for the building. 4. From Exhibit 4-3, find the 10-minute building attenuation factor, FR10, corresponding to your estimated o and the ventilation rate, Nv. 5. Estimate the release rate in lbs/min from the building attenuation factor and the airborne quantity (0.4Q) as follows, assuming the release takes place over 10 minutes: QRB = (FR10 x 0.4Q)/10 High-pressure receiver contains 14,500 lbs of ammonia Room size = 180,600 ft3 Hence: o = 180,600/(0.2 x 14,500) = 62 ft3/lb Nearest o on Exhibit 4-3 = 50 ft3/lb Ventilation rate = 44 room volumes/hour (131,310 ft3/min) Nearest Nv on Exhibit 4-3 = 40 room volumes/hour Therefore: o = 50 Nv = 40 FR10 = 0.85 (from Exhibit 4-3) QRB = (0.85)(0.4)(14,500)/10 = 493 lb/min The estimated worst-case release rate is then used to determine the distance to the toxic end-point. Exhibit 4-4 in the EPA guidance document is a table that equates the release rate to the distance to the toxic end-point for worst-case meteorological conditions (F stab ility, wind speed 1.5 meters per second). A mitigated release rate of 493 lb/minute in an urban setting equates to a toxic endpoint distance of 0.9 miles. The development in the area of the J.R. Simplot facility is a mix of commercial building, residences, and open areas that are slated for future development. Based on 40 CFR 68.22 (e) the facility is considered to be located in an urban area. The residential population within the 0.9-mile radius of influence was determined to be approximately 7,252. The population was determined by census block group centroid method using LandView? III, Environmental Mapping Software developed by the U.S. Department of Commerce Economics and Statistics Administration Bureau of the Census. The software will estimate the residential population within a given area using 1990 census information. A USGS Quadrangle map was used to determine environmental and public receptors. The USGS Quadrangle map used is listed below: ? Grand Forks, N. Dak., 1 963, photo revised 1979 Alternative Release Scenario One alternative release scenario was evaluated for the ammonia refrigeration process per USEPA 40 CFR 68.165(a)(2). The alternative release scenario considered is in accordance with the guidelines provided in 40 CFR 68.22 and 68.28. The scenario for the alternative release follows: A process line refrigeration system is put into defrost mode. An automatic valve fails to open causing pressure to build in the low-pressure receiver. The pressure in the low-pressure receiver causes the relief valve to open releasing ammonia to the atmosphere. It is estimated that it would take 10 minutes for the ammonia to be detected and the operator on shift to manually open the valve that failed to open automatically. This scenario would result in 45 pounds of ammonia being emitted to the atmosphere prior to the valve being opened. An ammonia release rate of 45 pounds in 10-minutes results in a release rate of 4.5 pounds per minute. Based on Exhibit 4-5 Distances to Toxic Endpoint for Anhydrous Ammonia (meteorological conditions D stability and wind speed 3 meters per second) from the EPA guidance document for refrigeration systems, a release rate of less than 10 pounds per minute results in a distance to a toxic endpoint of 0.1 miles in an urban setting. Based on 40 CFR 68.22 (e) the facility is considered to be located in an urban area. The residential population within the 0.1-mile radius of influence was determined to be approximately 2. The population was determined by block group proration method using LandView? III, Environmental Mapping Software developed by the U.S. Department of Commerce Economics and Statistics Administration Bureau of the Census. Determination of environmental and public receptors was completed in the same manner as detailed in the worst-case section. 68.155(d) Accidental Release Prevention Program The Prevention Program required for compliance with 40 CFR Part 68 for Program 3 processes is identical to the prevention program required under OSHA Process Safety Management. J.R. Simplot Company aligned its prevention program with OSHA in 1994. J.R. Simplot took the opportunity to revalidate their existing prevention program during the development of the Risk Management Plan. 68.155(e) Five-year Accident History No accidents, as described under 40 CFR 68.42(a), have occurred at this facility in the previous five years. 68.155(f) Emergency Response Program The emergency response program established by the J.R. Simplot Company does not require personnel to act as the site incident commander. In the case of an incident the Grand Forks Fire Department becomes the incident commander and assumes the role of directing response activities including any community emergency evacuation measures. Fire department staff train at the facility on an annual basis. 68.155(g) Safety Improvements The facility will be installing an additional leak detection system in the next fiscal year . The new system will consist of probes located outside of the compressor room. Each of the ammonia detecting probes will be connected to a local and remote alarm system. The local system will consist of a flashing red light and an audible horn. The remote system will be tied into the plant wide computerized alarm system. J.R. Simplot is currently in the process of evaluating the recommendations from the Process Hazard Analysis Revalidation completed in April 1999. Conclusion As part of J.R. Simplot Company's commitment to safety and respect for the hazards associated ammonia, an ammonia process management system was in place prior to the EPA RMP mandate. To comply with RMP, the current system for handling ammonia was re-evaluated updated as necessary. The RMP*Submit satisfies the requirement that the facility register and provide to the EPA a summary of their Risk Management Program for the ammonia refrigeration system. |