Wewahootee Water Treatment Plant - Executive Summary |
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CITY OF COCOA WEWAHOOTEE WTP RMP Executive Summary 1.0 Introduction and Background The USEPA's Clean Air Act Amendments of 1990 included provisions that require facilities that use certain substances to develop a plan to reduce the likelihood of an accidental release of the substances to the atmosphere and reduce the likelihood of serious harm to the public and the environment. The requirements of this plan, commonly referred to as a Risk Management Plan (RMP), are detailed and codified in 40 CFR Part 68. The City of Cocoa's Wewahootee Water Treatment Plant (WTP) is located within the Deseret Ranch Property and stores, chlorinates, and pumps groundwater to the Cocoa Claude H. Dyal WTP. The Deseret Ranch is a large property and the Wewahootee WTP is serveral miles from any public or environmental receptor. The Wewahootee WTP stores chlorine in quantities above the regulatory thresholds at which a RMP or a Process Safety Management Program (PSM) is required; however, since the facility is unmanned, it is exempt from the PSM regulation. The RMP consists of three compliance programs, each with progressively stricter compliance standards. The chlorination process at the WTP is subject to Program 1 (the least stringent of the three programs), because the WTP is not subject to the OSHA PSM Program, a worst-case release of chlorine should not affect the public, and the facility has had no accidents in the last five years. A Program 1 RMP consists of a limited hazard assessment and coordination with the local emergency planning council. The limited hazard assessment is done to determine the effects that a release of a regulated substance could have on the public and looks at only a worst case release scenario. 2.0 Hazard Assessment A hazard assessment was performed to determine the effects a release would have on the public. F or chlorine, the distance a set endpoint concentration of the gas would travel must be determined. In addition, an estimate of the population that could be affected by a release of chlorine was determined, and sensitive receptors such as hospitals, schools, and nursing homes were identified. The Program hazard assessment considers a single release scenario called "worst case"to determine if there could be any public or environmental receptors to confirm the RMP program level and compiles the five-year accident history for the chlorine process. 2.1 Worst-Case Release Scenario The regulations require the development of a worst-case release scenario based on conservative assumptions. For example, it is required to assume that the entire contents of the largest single container of chlorine will be released over 10 minutes. This is unlikely to occur since the properties of chlorine would cause a freeze and thaw cycle to occur at the leak, which would slow the release. The worst-case sc enario also requires that conservative atmospheric conditions be assumed which results in a large area of impact. The hazard assessment requires that the "toxic endpoint" or distance from the point of release to a location at which the chemical concentration equals or exceeds a certain concentration must be determined. That concentration is defined as the maximum airborne concentration below which individuals could be exposed for up to 1 hour without experiencing or developing irreversible or other serious health effects, or symptoms that could impair an individual's ability to take protective action. For chlorine, the toxic endpoint concentration is set a 3 parts per million (ppm) by volume. Because the cloud from a chlorine leak would disperse relatively quickly, an individual at a toxic endpoint would be exposed to the exposure limit concentration for much less than the 1 hour assumed by the limit. In addition, the exposure limit concentrations result in relatively minor health e ffects. Therefore, an individual at the toxic endpoint would be affected less than the results of the worst-case scenario may imply. For the Wewahootee WTP, the estimated distance to the toxic endpoint is 3 miles based on the EPA RMP*Comp Software Program. For the worst case scenario, the RMP regulations require an estimation of the residential population within the toxic endpoint circle. Additionally, the presence of public and environmental receptors such as schools, hospitals, prisons, public recreational areas, and major industrial or commercial areas must be identified. The Wewahootee WTP is located in an area surrounded by the Deseret Ranch Property that is used primarily for cattle grazing. The Deseret Ranch is one of the largest single properties in the State of Florida and is several hundreds of thousands of acres in size. Because of the remoteness of the Wewahootee WTP, there appears to be no known public or environmental receptors within the three mile radius of the wor st case release scenario. 2.1 Five-Year Accident History There have been no reportable accidents at the Wewahootee WTP between June 21, 1994, and the present date. 3.0 Emergency Response Program The Emergency Response Program develops a plan for dealing with a release. EPA RMP regulation 40 CFR 68 Subpart E require that an Accidental Release Emergency Response Plan be prepared. A facility in Program 1 is required to have coordinated with their local emergency planning council or local HAZMAT. The Cocoa's Emergency Response Plan provides specific emergency response procedures for accidental releases of chlorine and they have coordinated with the Orange County Fire and Rescue Department concerning emergency planning. |