Atlantic Coast Polymers, Inc. - Executive Summary |
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Atlantic Coast Polymers, Inc.'s (ACP) accidental release prevention policy involves a unified approach that combines technologies, procedures and management practices. All applicable prevention procedures of the U.S. Environmental Protection Agency's (EPA) Risk Management Program (RMP) will be adhered to. The ACP's process safety management program's emergency response policy involves the preparation of evacuation and notification procedures and coordination of emergency response procedures with the Plainfield Fire Company, local police department and the Local Emergency Response Committee (LEPC). ACP is located at 12 East Parkway, Plainfield, Connecticut. The plant stores dimethylamine (DMA) and formaldehyde (as formalin) in quantities that exceed threshold for a RMP. 5,200 gallons of each chemical are stored on site year round for the polymerization process (described below). Polymerization of acrylamide is an old technology dating back to the mid-late 1940's. ACP is a manuf acturer of water soluble polymers using acrylamide monomer which is polymerized as a 5% solution in water in the first stage reactor. The resultant acrylamide polymer yields a viscous water solution which is pumped to the second reactor. To this reactor, in sequence, aqueous (40%) dimethylamine (DMA) is added followed by the addition of a 37% Formalin solution (formalin). The resultant reaction product is a 6 - 7% aminomethylated polyacrylamide solution which is transferred to bulk storage tanks. Principal applications include use as an aid to suspend solids settling in wastewaters, sludge dewatering in sewage treatment plants and as a processing aid in paper manufacturing. 40% DMA is a flammable liquid. A bulk storage tank containing up to 5,200 gallons of DMA is stored in an enclosed building with a cement pad, a dike and a common fire wall with the main plant. This isolates the tank and its contents from the main plant. Bulk DMA is transferred to a 600 gallon DMA meas uring tank with a sight glass located near the Stage II reactor. Observation of the liquid level shows product transfer. The 37% formalin is a toxic liquid in which solution is transferred from a diked bulk storage tank to a 600 gallon measuring tank also fitted with a sight glass. The contents of the measuring tank are transferred to the Stage II reactor where mixing and re-circulation of contents increase the temperature of about 10 degrees F. After mixing of the batch, it is transferred to finished product bulk storage tanks. ACP's off-site consequence analysis includes consideration of two release scenarios involving DMA and the formalin. These scenarios are identified as "worst-case" and "alternative." EPA states that for the worst-case scenario "the owner or operator shall assume that the maximum quantity in the largest vessel is released as a gas over 10 minutes". The worst-case scenario is to result from an unspecified failure. EPA defines the alternative scenario as one that is "more likely to occur that the worst-case scenario". The purpose of the release scenarios is to determine the distance to "toxic endpoint", which is defined by the American Industrial Hygiene Association as the "maximum airborne concentration below which it is believed that nearly all individuals could 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". Additionally, the residential population within a circle, which is made using the distance to toxic endpoint as its radius, has to be defined as an estimate of the population potentially affected. For the purpose of determining worst-case and alternative release scenarios distance to toxic endpoint, ACP utilized EPA's RMP*Comp software. The worst-case release scenario involving formalin includes the release of 48,880 lbs at the shipping temperature of 100 degrees F. The distance to toxic endpoint was determined to be 9.3 miles and an estimate of the residential population potentially affected of 48,200 was obtained. ACP used, as an alternative release scenario, the rupture of a two inch pipe which carries the folmalin from the 5,200 gallon storage tank to the reactor. The distance to toxic endpoint for the alternative scenario was determined to be 0.1 miles and an estimate of the residential population potentially affected of 8,856 was obtained. The worst-case accidental release scenario involving dimethylamine includes the release of all 39,960 lbs inside the storage tank. This scenario includes as fire wall and dike for active mitigation controls. The distance to toxic endpoint was determined to be 0.2 miles and an estimate of the residential population potentially affected of 20 was obtained. ACP used, as an alternative release scenario, the rupture of a two inch pipe which carries the dimethylamine from the 5,200 gallon storage tank to the reactor. The distance to toxic endpoint for the alternative scenario was determined to be 0.1 miles and an estimate of the residential population potentially affected of 4 was obtained. The ACP process safety management program is based on training of the operators, implementation of preventive maintenance, auditing and inspection programs; continual review and upgrade of process and safety equipment; use of accurate and effective operating procedures (developed with the participation of the operators); and execution of periodic hazard reviews of equipment and procedures. No accidental releases of either DMA or formaldehyde have occurred at the ACP Plant in the past five years. The plant has coordinated its emergency response procedures with the Plainfield Fire Company, Police Department and the LEPC. Procedures, outlined in the process safety management program, have been developed for the effective and timely notification of response personnel and the community and for the safe evacua tion of employees. |