U S Chemical-Watertown - Executive Summary |
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1. Introduction A Risk Management Program (RMP) has been implemented at the U S Chemical Watertown warehouse for the reduction of accidental releases of hazardous materials. This RMP summarizes the management, administrative, procedural, and technological controls that work together to minimize the risk to the community of hazardous chemical releases. The RMP summary is organized to correspond with specific Environmental Protection Agency (EPA) RMP definitions and requirements, including: < Introduction; < Safety policies to protect health and the environment; < Facility identification and regulated substances covered processes; < Hazard Assessment and off-site consequence analysis; < Five-Year Accident History; < Emergency Response Plan. 2. Health, Environment, and Safety Policies Risk management and safety are important concerns at U S Chemical. This RMP formalizes and documents these activities. The Watertown warehouse is committed to conducting its operations in a safe and responsible manner and to reducing risks to human health and the environment. 3. Facility identification and Regulated Substances Covered Processes Liquefied petroleum gas (LPG) propellant contains several components that are classified as flammable materials under the RMP mixture regulations. LPG is used as a propellant in aerosol cans, which are stored within the U S Chemical warehouse located at 1007 S. 12th Street in Jefferson County, Wisconsin. The LPG mixture is regulated under 40 CFR Part 68, the EPA Risk Management Program (RMP) Rule.The facility's LPG propellant (aerosol can products), which has a capacity of 47,000 pounds, is the process that exceeds the RMP flammable substance mixture threshold of 10,000-pounds. 4. Hazard Assessment The RMP regulations define a worst-case release as "the release of the largest quantity of a regulated substance from a vessel or process line failure that results in the greatest distance to an endpoint defined in Sections 68.22 (a)" (4 0 CFR 68.3). For regulated flammable substances (e.g., butane), the endpoint is defined as an overpressure of 1 pound per square inch (psi) resulting from an unconfined vapor cloud explosion. According to the Off-Site Consequence Analysis Guidance, in a worst-case release involving a flammable gas, the substance forms a vapor cloud, which then detonates (U.S. EPA, May 1996). Ten percent of the total energy available for explosion has been assumed to contribute to the explosive effect (40 CFR 68.25(e)). The distance to the overpressure level of 1 psi is then calculated. Furthermore, for simplicity, the worst-case analysis may be based on the predominant flammable component of the mixture or a major component with the highest heat of combustion. Radian has chosen to implement the former in the worst-case analysis for this process. A Trinitrotoluene (TNT) equivalent equation based on the worst-case scenario OCAG calculation method presented in the RMP Offsite Consequence Analysis Guid ance (US EPA, April 15,1999) was used to calculate the distance to the overpressure endpoint for the LPG propellants. Using these calculations, a 1 psi overpressure vapor cloud explosion can go a distance of 33 feet. 5. Five-Year Accident History There have not been any accidental releases from the LPG process within the last five years that meet the definition in the RMP regulations. 6. Emergency Response Plan The RMP regulations require that "response actions have been coordinated with local emergency planning and response agencies" (40 CFR 68.12(b)(3)). Emergency response activities at the Watertown facility are coordinated with the Jefferson County LEPC and the Watertown Fire Department. Depending on the quantity and chemical involved in a "reportable spill," certain local, state, and federal emergency planning and response agencies are also notified. |