Winter Garden Citrus Plant - Executive Summary |
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Risk Management Plan 1.1. Introduction This Risk Management Plan (RMP) was prepared by O'Brien & Gere Engineers, Inc. (O'Brien & Gere) on behalf of Winter Garden Citrus Incorporated (WGCI) Winter Garden facility. The plan was prepared to fulfill the requirements of Section 112(r)(7) of the Clean Air Act (CAA) pursuant to United States Environmental Protection Administration (USEPA) regulations contained in 40 Code of Federal Regulations (CFR) Part 68, Sections 68.1-68.220, Accidental Release Prevention Provisions. These regulations require stationary sources with listed substances present in a process in greater than the threshold quantity to develop and implement a risk management program that includes a hazard assessment, a prevention program, and an emergency response program. The risk management program must be described in an RMP that must be registered with USEPA, submitted to appropriate agencies, and made available to the public. In the Winter Garden facility, anhydrous ammonia, which is a listed toxic substance in the RMP regulations, is stored in greater than the threshold quantity of 10,000 lb. This RMP was prepared in accordance with 40 CFR 68, Subpart G, 68.150-68.190, which describes the format of the written RMP. An updated RMP, including an updated offsite consequence analysis, is required within five years of its initial submission or its most recent update. A compliance audit to certify compliance with the provisions of the RMP regulations is required at least every three years. The written RMP was developed based upon site visits conducted by O'Brien & Gere between the months of May and August of 1998. During the site visits, the ammonia refrigeration system was inspected; system design and operating procedures and information were collected; and personnel responsible for environmental activities, emergency planning and coordination, and system operation and maintenance were interviewed. A review of the system accident history and the facility Emergency Response Plan was also conducted. A hazard assessment consisting of one worst-case and one alternate-case release scenario was completed. The hazard assessment was conducted in accordance with 40 CFR 68 regulations, as well as guidance provided by the USEPA RMP Offsite Consequence Analysis (OCA) document. The hazard assessment is detailed in the following section. A Program 3 Prevention Program was prepared based on a review of the system and its associated operating, maintenance, and training procedures. 1.2. Hazard Assessment Winter Garden Citrus, Inc. processes citrus fruit and juices at its Winter Garden facility. Ammonia refrigeration systems are used to freeze concentrate and to chill stored product. Separate systems are used to supply the different cold rooms and freezing tunnel. In the Winter Garden facility, anhydrous ammonia, which is a listed toxic substance in the RMP regulations, is stored in greater than the thr eshold quantity of 10,000 lb. The facility's accidental release prevention and emergency response procedures are based on the goal of storing and handling ammonia to prevent exposure to employees and the nearby community. It is Winter Garden Citrus policy to adhere to applicable state and federal regulations. The ammonia refrigeration system is designed in accordance with applicable regulations and design standards. Ammonia use is based on safe handling procedures and training of personnel. The facility's Emergency Response Plan includes procedures for emergency response and notification of the local fire department and the local emergency planning commission (LEPC) in the event of fire, explosion, or ammonia release to the environment. 1.2.1. Worst-Case Release Scenario In accordance with 40 CFR 68 Subpart B - Hazard Assessment, facilities which are defined as Program 3 are required to include an off-site consequence analysis and a worst-case release scenario analysis in the RMP for the facility. For the purpose of initiating the development of an RMP for the Winter Garden facility, and in accordance with 40 CFR 68 Subpart B, one worst-case release scenario was evaluated. In accordance with 40 CFR Part 68.25(b)(1), the worst-case release scenario was defined to be the release of the greatest amount held in a single process vessel line. The receiver located outside of the main building was determined to hold the largest quantity of ammonia of any vessel for the site, 8,000-lb. The USEPA provides guidance specifically for ammonia refrigeration systems in its Model Risk Management Program and Plan for Ammonia Refrigeration. The model plan is based on the following conditions, which are generally applicable to the Winter Garden facility: 7 The worst case quantity released is equal to greatest amount held in the largest vessel. 7 Because ammonia is a vapor at ambient temperature and is held as a liquid under pressure in most parts of the system, the total mass is considered to be released over a period of 10 minutes. 7 Typical minimum weather conditions are wind speed of 1.5 meters per second and F stability class. 7 The toxic endpoint is 0.14 mg/L. The Winter Garden facility is located in a primarily industrial/residential area and should therefore be classified as urban. Using Table 2-1 of the model plan, 8,000 lb. of ammonia released in an urban area would give a predicted distance to the toxic endpoint of 5,600 feet or 1.06 miles. In accordance with 40 CFR 68.30, the off-site impacts resulting from a worst-case release scenario are evaluated by estimating the population within a circle with its center at the point of release and a radius equal to the distance to the endpoint. Therefore, under a worst-case release scenario, a circle with a radius of 5,600 ft. or 1.06 miles around the facility would be affected. This circle is depicted on the attached Figure 1. Winter Garden lies within Orange County, Florida. According to the latest information attainable from the U.S. Census Bureau, Orange County has a population density of 746-persons/square mile. Based on this population density, it is estimated that 2600 people would be potentially impacted under the worst-case release scenario. Furthermore, based on site visits of the Winter Garden facility and the review of USGS maps for the area, several public receptors are located within the radius of significant impact. These receptors include housing subdivisions, businesses such as the Continental Can Co., one public swimming pool, one public park (Irrgain Park), and three schools (Dillard Street Elementary School, the West Side Votech Center and Maxey Elementary School). 1.2.2. Alternate Release Scenario In accordance with 40 CFR 68.28, the facility is required to identify and analyze at least one alternative release scenario for inclusion in the RMP. Based on the Model Risk Management Program and Plan for Ammonia Refrigeration, O'Brien & Gere selecte d the alternative scenario and evaluated the impact associated with a leak in the evaporative condensers on the roof of the main building. A likely scenario would be a burst or broken supply line. According to Winter Garden Citrus Inc. personnel and based on facility operations, this release would last for a duration of approximately 10 minutes and represents an alternative release scenario which could reasonably be expected to occur at the Winter Garden facility. As shown in the following calculations, the ammonia release rate from a leak in the evaporative condenser was estimated utilizing methodology provided in USEPA's Model Risk Management Program and Plan for Ammonia Refrigeration and the OCA document. The OCA document provides equations for modeling the release rate of gases for the alternate scenario while the model plan provides predicted distance tables specific to ammonia releases. From Equation No. 11 of the OCA for unmitigated releases of gases under alternate release s cenarios, QR = HA x Pt x 1/V(Tt) x GF = 2.50 in2 x 195 psia x 1/V(308) x 14 = 389 lb/min QR = Release rate (pounds per minute) HA = Hole area (square inches) Pt = Tank pressure (pounds per square inch - absolute) Tt = Tank temperature (K) GF = Gas factor, incorporates conversion factors, from OCA guidance This equation gives a conservative estimate of the release rate since it does not account for the decrease in pressure as the system is evacuated or the pressure loss along the length of pipe. This should make up for any uncertainty in estimating the size of the leak. From Table A-1 of the model plan, the distance to the toxic endpoint corresponding to a rate of release of 389 lb/min is approximately 1315 ft or 0.25 miles. A release of this magnitude has the potential to affect off-site receptors since the minimum distance from the release site to the nearest property line of WGCI's facility is less than 1000 feet. Based on the calculations, the distance to the toxic endpoint is 1350 ft. 40 CFR 68.30(b) states that an alternative release scenario must reach an endpoint off-site, unless no such alternative release scenario exists. Therefore, the alternative release scenario defined by this report satisfies this requirement. In accordance with 40 CFR 68.30, the off-site impacts resulting from the alternate release scenario are evaluated by estimating the population within a circle with its center at the point of release and a radius equal to the distance to the endpoint. Therefore, under the alternate release scenario, a circle with a radius of less than 1350 ft. around the point of release would be affected. Based on the population density of 746 people per square mile, it is estimated that a maximum of 150 people would be potentially impacted under the alternate release scenario. Furthermore, based on site visits to the Winter Garden facility and review of USGS maps for the area, several public receptors are located within the radius of significant impac t. A residential area and a public swimming pool are located immediately adjacent to the site to the north. Various businesses located adjacent to the facility also have the potential to be impacted depending on weather conditions. However, the typical prevailing wind direction, obtained from National Weather Service data, is from the north and would tend to concentrate the vapor cloud over WGCI property. 1.2.3. Documentation, Review and Update WGCI shall maintain records of the off-site consequence analysis at the facility. A copy of this report with a description of both the worst and alternate case scenarios, all assumptions and documentation, release rates and amounts, and distance to endpoints will meet this requirement. Affected population and environmental receptors should also be included. WGCI shall review and update the consequence analysis at least once every five years. If changes in processes, quantities stored or handled, or any other aspect of the stationary sou rce might reasonably be expected to increase or decrease the worst-case distance to the endpoint by a factor of two or more, WGCI shall complete a revised analysis within six months of the change and submit a revised RMP. 1.2.4. Five Year Accident History Two accidental releases of ammonia have occurred since Louis Dreyfus Citrus Inc. purchased the company on September 18, 1996. Both incidents were minor in scope. The first incident occurred on 12/4/98 when an operator neglected to verify all drain valves on a juice cooler were secured prior to putting the unit on-line. The operator corrected the condition almost immediately. A contractor crew was working near the drain location with one individual within 6 feet of the drain discharge. All persons except the individual near the drain evacuated the location with no ill effects. The individual near the drain discharge was exposed to the discharge. This individual was taken to a local clinic to be checked for any possible to xic effects of the exposure. The individual was treated and released with no serious injuries. The extent of the discharge was estimated to be less than 25 pounds of ammonia in gaseous form. The facilities Emergency Response Team responded to the release and evacuated and secured the area until the gas dissipated. The release at no time represented an off-site hazard. The winter garden Fire Department was not contacted for assistance as the release was small and the condition corrected immediately. Training and operating procedures have revised to emphasize the necessity of performing pre-startup inspections. In addition a valve lockout removal authorization program has been implemented. The second incident occurred on 4/8/99 when a valve bonnet became loose and separated while being manipulated by an operator. The valve in question is used to drain water and oil from its associated separator vessel. The operator was able to re-secure the valve bonnet in a relatively shor t time (estimated at 2-3 minutes). There was no evidence of direct ammonia release to atmosphere except via ammonia contained in the water leaking from the valve. The facilities Emergency Response Team responded to the incident and evacuated and secured the area until the ammonia evaporated from the water and dissipated. The extent of the discharge was estimated to be less than 20 pounds of ammonia in an evaporated gaseous form. No injuries occurred during the incident and the release at no time represented an off-site hazard. The winter garden Fire Department was not contacted for assistance as the release was small and the condition corrected immediately. Training and maintenance programs have been revised to make operators aware of the potential for this hazard in the future. 1.3. Prevention Program and Emergency Response Plan The ammonia refrigeration system complies with USEPA's RMP regulations and other applicable regulations. Safety information, including a Materia l Safety Data Sheet (MSDS) for anhydrous ammonia, maximum inventory, and equipment specifications and codes are maintained. Personnel responsible for operating and maintaining the ammonia refrigeration system have been thoroughly trained and tested for competency in understanding the hazards of the system, how to avoid or correct unsafe conditions, and in the written operating, inspection, and maintenance procedures. The procedures were developed according to industry and company standards, and according to 40 CFR 68. Refresher training, both classroom and on the job, is provided at least every three years. Receiver tank levels are checked daily. Written maintenance procedures have been developed for ammonia use and storage. Various maintenance checks occur on a daily, weekly, or monthly basis. 1.3.1. Prevention Program Review The prevention program is intended to assure that the plant and equipment are in conformance with safe design principles and that the operation, maint enance and control of hazard procedures are complete and accurate. 1.3.2. The Emergency Response Plan The facility has a written Emergency Response Plan (ERP) which describes emergency response management procedures to be utilized for an ammonia release. This plan enables WGCI personnel to act promptly in the event of an ammonia release within the facility. The ERP details responsibilities for individual plant personnel, coordination with outside responders, emergency equipment and training, evacuation, and emergency medical treatment. The Winter Garden and Orange County Fire Departments were consulted during the development of the ERP. 1.3.3. Management System The RMP management system assigns responsibility for implementation of the prevention program. The management system is intended to ensure that each element is fully and effectively carried out. At WGCI, it is the responsibility of the plant manager to assign the relevant portions of the plan to the appropriate personn el. The safety coordinator shall ensure that the plan is up to date and available to facility personnel. |