DuCoa - Executive Summary |
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DUCOA, 299 EXTENSION STREET, VERONA, MO 65769 FACILITY DESCRIPTION, REGULATED SUBSTANCE, ACCIDENTAL RELEASE PREVENTION AND EMERGENCY RESPONSE POLICIES: DuCoa manufacturing facility handles, ethylene oxide, methyl chloride, and trimethylamine, in which all are listed as a Regulated Substance under 40 CFR Part 68 and are present in quantities that exceed the threshold quantity for applicability of EPA's Accidental Release Prevention Program. Ethylene oxide, methyl chloride (toxic chemicals) and trimethylamine (flammable chemical) are utilized at this facility for the manufacture of nutritional animal food products for the poultry, beef, dairy, and companion animal industry. DuCoa's commitment to providing a safe, healthy work environment for employees as well as providing a safe, healthy environment for the surrounding community is supported by the incorporation of the latest technology in process controls, active mitigation, passive mitigation, and monitoring detection systems. Du coa adheres to all applicable Federal, State and local safety and environmental regulations for the prevention of releases of these chemicals. All information regarding DuCoa's Risk Management Plan has been submitted to EPA utilizing EPA's RMP* Submit software program. It should be noted that the RMP* Submit software program does not allow a facility to assign a Process ID number. The process ID number is automatically generated by EPA and does not necessary represent the number of regulated processes at this facility. For example, the three processes regulated under this standard are assigned Process ID 2, Process ID 3, and Process ID 4. The purpose of this number as provided by the RMP* Submit software is to help facilities track multiple processes. The same holds true for the id numbers represented in the worst-case and alternative release scenarios in Section 2 and Section 3 of the RMP data elements. WORST-CASE SCENARIO: EPA has defined a worst-case release as, "a release of the largest quantity of a regulated substance from a vessel or process line failure that results in the greatest distance to a specified endpoint." Administrative controls that limit the quantity of a substance in a vessel or pipe can be considered when determining the worst-case scenario. The possible causes of the release or the probability that such a release might occur is not considered in the worst-case scenario analysis, the release is simply assumed to take place. All releases are assumed to take place at ground level. It is only required to document on the actual RMP a worst-case scenario for one toxic chemical and for one flammable chemical. Therefore, you will find that the worst-case scenario for Ethylene oxide is the only chemical used in the RMP for the worst-case scenario for toxic substances due to the fact that the worst-case scenario for Ethylene oxide had the largest area of off-site impact. Meteorological conditions for the worst-case scenario are defined by EPA Guidance as atmospheric stability class F (stable atmosphere), wind speed of 1.5 meters per second (3.4 miles per hour), and ambient air temperature of 25 degrees C. Two choices are provided for topography for the worst-case scenario, rural or urban. It should be noted that the calculations and numbers used in the following summary vary from the numbers entered in the data elements of the RMP due to EPA requiring rounding to certain significant digits. The worst-case scenarios for DuCoa's regulated toxic and flammable substances are as follows: WORST-CASE SCENARIO FOR ETHYLENE OXIDE - TOXIC SUBSTANCE The worst-case scenario release was determined by taking the greatest amount held in a vessel in the process, taking into account administrative controls that limit the maximum quantity. The largest vessel in the process (Ethylene oxide tank) has a total capacity of 175,000 lb. The tank is located outside the building thus no mitigation measures are in place for the vess el. No administrative controls limit the total amount of capacity of the tank. The estimated distance to the toxic endpoint of 0.090 mg/L (ERPG-2 basis) was determined by utilizing EPA's RMP* Comp software program. EPA requires that regulated substances that are gases at ambient temperature should be considered gases for consequences analysis. Ethylene oxide, although liquefied under pressure, is a gas under ambient conditions. Therefore, the release scenario would be considered a toxic gas release. The entire contents of the vessel are assumed to be released over a period of 10 minutes. A wind speed of 1.5 meters per second and an atmospheric stability class of F was used in calculating the worst-case scenario per Risk Management Guidance, and the topography of the area surrounding the property is rural. The toxic endpoint for ethylene oxide is 0.090 mg/L. Per the EPA guidance document mentioned above, "this airborne concentration has been published by the American Industr ial Hygiene Association (AIHA) and is the maximum airborne concentration below which is believed that nearly all individuals can be exposed for up to one hour without experiencing or developing irreversible or other serious health effects or symptoms which could impair an individual's ability to take protective action". Using these parameters it was determined (using EPA* Comp.) that with a release of 175,000 lb., an estimated distance to the toxic endpoint is 12 miles. WORST-CASE SCENARIO FOR TRIMETHYLAMINE - FLAMMABLE SUBSTANCE According to EPA guidance document "RMP Offsite Consequence Analysis Guidance - May 24, 1996". The worst-case scenario would involve the release of the entire contents of the tank as a vapor, which finds an ignition source. As a conservative assumption, 10 percent of the flammable vapor in the cloud is assumed to participate in the explosion. For flammable substances such as trimethylamine, the worst-case release is assumed to result in a vapor cloud con taining the total quantity of the substance that could be released from a vessel or pipeline. The entire quantity in the cloud is assumed to be between the upper and lower flammability limits of the substance. For the worst-case consequence analysis, the vapor cloud is assumed to detonate. The endpoint for the consequence analysis of a vapor cloud explosion of a regulated substance is an overpressure of 1 pound per square inch (psi). This endpoint was chosen by EPA as the threshold for potential serious injures to people as a result of property damage caused by an explosion (e.g. injuries from flying glass from shattered windows or falling debris from damaged houses). The worst-case scenario release was determined by taking the greatest amount held in a vessel in the process, taking into account administrative controls that limit the maximum quantity. The largest vessel in the process (Trimethylamine tank) has a total capacity of 145,000 lb. The tank is located outside the buil ding thus no mitigation measures are in place for the vessel. No administrative controls limit the total amount of capacity of the tank. A wind speed of 1.5 meters per second and an atmospheric stability class of F was used in calculating the worst-case scenario per Risk Management Guidance, and the topography of the area surrounding the property is rural. The estimated distance to the overpressure of 1 psi using the parameters listed above is 0.4 miles. Public receptors reported on the RMP that are located within this endpoint radius of 0.4 miles include, residences, major commercial, office and or industrial areas. It should be clarified that only small offices/building are located within this radius and do not include major commercial areas. ALTERNATIVE RELEASE SCENARIO: EPA requires that an alternative scenario be analyzed for each regulated toxic chemical and one alternative scenario analyzed for all regulated flammable substances. The release scenario must include conside ration of the following: 1. Transfer hose releases due to splits or sudden uncoupling; 2. Process piping releases from failures at flanges, joints, welds, valves and valve seals, and drains or bleeds; 3. Process vessel or pump releases due to cracks, seal failure, drain bleed, or plug failure; 4. Vessel overfilling and spill, or overpressurization and venting through relief valves or rupture disks; and 5. Shipping container mishandling and breakage or puncturing leading to a spill. In determining the alternative release scenarios for toxic chemicals, a scenario should be used that lead to concentrations above the toxic endpoint beyond the fenceline. Scenarios for flammable chemicals should have the potential to cause substantial damage, including on-site damage. Consideration of active mitigation systems, such as interlocks, shutdown systems, pressure relieving devices, flares, emergency isolation systems, and fire water and deluge systems as well as passive mitigation are allowed to be considered. Meteorological conditions for the alternative release scenario are defined by EPA Guidance as atmospheric stability class D, wind speed of 3.0 meters per second, and ambient air temperature of 25 degrees C and 50 percent humidity. Two choices are provided for topography for the alternative release scenario, rural or urban. The alternative release scenarios for both toxic chemicals and one flammable substance is as follows: ALTERNATIVE RELEASE SCENARIO FOR ETHYLENE OXIDE - TOXIC SUBSTANCE The alternative release scenario identified for the Ethylene oxide process would be a gasket or line failure downstream of the pump. The initial operational flow rate of ethylene oxide (363 lb./min or 50 gpm), the cross-sectional area of pipe (3.355 square inches), the operational pipe pressure (50 psi) and the change in pipe elevation (10 ft) was used to calculate the release rate (6,260 pounds per min). The release duration is 5 minutes. Active mitigation (emergency shutdow n) was determined to be activated in a maximum time of five minutes. (Five minutes was determined to be sufficient time to detect and stop the leak because of continuous camera monitoring and monitoring of unloading operations by qualified personnel). This release occurs outside with no passive mitigation present. The topography is rural surroundings. A wind speed of 3 meters/second, a stability class D and an air temperature of 77 degrees F are assumed for alternative release scenarios utilizing the RMP* Comp software analysis program. Using these parameters it was determined (using RMP* Comp) that with a release rate of 6,260 pounds per min over 5 minutes would result in an estimated distance to the toxic endpoint of 2.4 miles. Public receptors reported on the RMP that are located within this endpoint radius of 2.4 miles include schools, residences, major commercial, office and or industrial areas. It should be clarified that only small offices/building are located within this radius and do not include major commercial areas. ALTERNATIVE RELEASE SCENARIO FOR METHYL CHLORIDE - TOXIC SUBSTANCE The alternative release scenario identified for the Methyl chloride process would be a gasket failure on the pressure side of the pump. The initial operational flow rate of methyl chloride (383.87 lb./min or 50 gpm), the cross-sectional area of gasket (3.355 square inches), the operational pipe pressure (50 psi) and the change in pipe elevation (10 ft) was used to calculate the release rate (6,750 pounds per min). The release duration is 5 minutes. Active mitigation (emergency shutdown) was determined to be activated in a maximum time of five minutes. (Five minutes was determined to be sufficient time to detect and stop the leak because of continuous camera monitoring and monitoring of unloading operations by qualified personnel). This release occurs outside with no passive mitigation present. The topography is rural surroundings. A wind speed of 3 meters/ second, a stability class D and an air temperature of 77 degrees F are assumed for alternative release scenarios utilizing the RMP Comp* software analysis program. Using these parameters it was determined (using RMP* Comp) that with a release rate of 6,750 pounds per min over 5 minutes would result in an estimated distance to the toxic endpoint of 0.8 miles. Public receptors reported on the RMP that are located within this endpoint radius of 0.8 miles include, residences, major commercial, office and or industrial areas. It should be clarified that only small offices/building are located within this radius and do not include major commercial areas. ALTERNATIVE RELEASE SCENARIO FOR TRIMETHYLAMINE - FLAMMABLE SUBSTANCE According to EPA RMP guidance, four possible scenarios involving flammable substances include: 1. Vapor Cloud Fire 2. Pool Fire 3. BLEVE - Boiling liquid, expanding vapor explosion 4. Vapor Cloud Explosion 5. Jet Fire Due to the characteristics of trimethylam ine, it was determined that a vapor cloud fire would be the most likely event resulting from a release. A vapor cloud fire (flash fire) is assumed to result from dispersion of a cloud of trimethylamine vapor and ignition of the cloud following dispersion. Such a fire could flash back and could represent a severe heat radiation hazard to anyone in the area of the cloud. The lower flammability limit for trimethylamine is 48 mg/L, which represents the maximum distance at which the radiant heat effects of a vapor cloud fire might have serious consequences. Vapor cloud fires are considered instantaneous events, therefore release duration does not need to be considered for estimating vapor cloud fire distances. The alternative release scenario identified for the trimethylamine process would be a gasket or line failure downstream of the pump. The initial operational flow rate of trimethylamine (267.04 lb./min or 50 gpm), the cross-sectional area of pipe (3.355 square inches), the operat ional pipe pressure (50 psi) and the change in pipe elevation (10 ft) was used to calculate the release rate (5,330 pounds per min). This release occurs outside with no passive mitigation present. Active mitigation such as a sprinkler system, deluge system, water curtain, or excess flow valve are not present at this location in the process. However, a manual emergency shutdown system is in place and can be utilized in the event of a release. The topography is rural surroundings. A wind speed of 3 meters/second, a stability class D and an air temperature of 77 degrees F are assumed for alternative release scenarios utilizing the RMP* Comp software analysis program. The estimated distance to the lower flammability limit (48 mg/L) using these parameters in EPA's RMP* Comp software analysis program is 0.1 mile. ACCIDENT RELEASE PREVENTION PROGRAM: DuCoa complies with the Process Safety Management rule of OSHA standard 29 CFR 1910.119 for the prevention of hazardous chemical re leases and is therefore subject to the requirements of EPA's Program 3 instead of Program 2. It should be noted that no data is reported for Program 2 in the RMP Submit data because DuCoa is subject only to Program 3. Program 3 (which is OSHA's Process Safety Management Plan) is a comprehensive program with fourteen elements, including process hazard analysis, employee training, operating procedures, mechanical integrity, pre-safety startup, contractor safety, emergency planning and response, compliance auditing, and employee participation. The Process Safety Management Program ensures that the processes and the equipment in the processes are designed, constructed, and maintained according to industry codes and standards and that the processes follow good engineering practices. The mechanical integrity element of the program includes continuous inspections and testing of equipment and monitoring devices in the processes to detect any deficiencies and correct them before it contribu tes to a potential release incident. All elements of the Process Safety Management Program help to ensure an uncontrolled, release of ethylene oxide, methyl chloride, and or trimethylamine is prevented. FIVE YEAR ACCIDENT HISTORY: No releases of ethylene oxide, methyl chloride, or trimethylamine have occurred at DuCoa in the past five years. EMERGENCY RESPONSE PROGRAM: DuCoa has developed an emergency response plan (in accordance with 29 CFR 1910.38) that includes provisions to evacuate employees from the facility in the event of an uncontrolled accidental release of a hazardous chemical. It is DuCoa's policy to contact the local emergency planning committee, and the local fire department (Aurora Rural Fire Department) in the event of a hazardous chemical release. DuCoa has contracted an emergency response group (Environmental Management, Inc.) that will respond to any hazardous chemical releases and any cleanup operations. DuCoa has coordinated with the local emergency plann ing committee on its emergency response plan, and in the unlikely event of an uncontrolled release, they will notify any affected neighbors or surrounding properties if an evacuation is necessary. PLANNED CHANGES TO IMPROVE SAFETY: DuCoa is continuously improving the safe operation of the ethylene oxide, methyl chloride and trimethylamine processes by implementing preventative maintenance programs, inspection programs, and employee training in the safe operation of the equipment and the system. All regulated processes are designed in accordance with good engineering practices. Periodic auditing of the Process Safety Management Prevention Program ensures that any system changes or modifications are evaluated and necessary safety precautions and or safety improvements are made before the process is placed into operation. |