R. M. Clayton WRC - Executive Summary |
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In accordance with Title 40 of the Code of Federal Regulations, Chapter 68, Subpart G, Section 155 (40 CFR 68.155), under section 112(r) of the Clean Air Act Amendments (CAAA), the R. M. Clayton Water Reclamation Center (WRC) located at 2440 Bolton Road, Atlanta, Georgia, has established an Executive Summary of the Risk Management Plan. The R. M. Clayton WRC is required by federal law and state permit to limit the concentration of bacteria and viruses prior to discharge of reclaimed water to the Chattahoochee River. The facility accomplishes this goal by utilizing chlorine to disinfect the reclaimed water thus protecting public health and the environment from such pathogens. If released to the atmosphere in sufficient quantities, chlorine can be harmful to humans or the environment. The R. M. Clayton WRC has developed a Risk Management Plan and Program to help prevent a harmful release of chlorine and is prepared to respond in case such a release occurs. Please note, the current c hlorine disinfection process will be replaced by an ultraviolet (UV) disinfection system by 2001. Substantially reduced amounts of chlorine may remain on-site as a backup to the UV system for a limited time. A second process has also been determined to be subject to the 112(r) requirements. As part of water reclamation, the natural breakdown of solids which have been separated from the water occurs in structures known as digesters. The digestion process at the R. M. Clayton WRC generates digestion gas containing flammable concentrations of methane. The digester gas is either stored, flared, or burned as an alternative fuel source for process sludge incineration or drying. An accidental release of digester gas could result in fire or explosion because of the methane content of the gas. The R. M. Clayton WRC has developed a Risk Management Plan and Program to help prevent a potentially flammable or explosive release of digester gas and is prepared to respond in case such a release occurs. For each covered process, disinfection (chlorine) and digestion (methane), worst-case and alternative scenarios were developed to assess the possible consequences of accidental releases of these substances. Worst-case scenarios involved estimation of the impact of a rapid, complete release under artificially adverse weather conditions, however unlikely the conditions and parameters might be. The developed alternative scenarios estimate the impact based on more realistic release parameters under typical meteorological conditions. The worst-case scenario for chlorine involved the release of the entire contents of a single chlorine vessel, while the alternative case described the results of a failure of the subheader connected to the chlorine vessel. The worst-case scenario for methane was modeled on a vapor cloud explosion of the entire contents of the largest vessel in the digester gas system. The alternative case for methane was based on a vapor cloud fire from an accide ntal release from a digester unit roof vent. The Environmental Protection Agency (EPA) developed and approved software package, RMP*Comp, was utilized to estimate the toxic, explosive and flammable endpoint distances for the release scenarios. Another EPA-approved software package, LandView III, as well as other available information, were employed to identify public and environmental receptors within the extents identified by RMP*Comp. Specific values from these calculations are provided in Sections 2 through 5 of the Risk Management Plan and Chapter 2 of the Risk Management Program. The calculations did not account for active or passive mitigation measures. There have been no accidents involving substantial chlorine or methane releases that resulted in on-site or off-site injury, property damage, environmental damage, evacuations or sheltering within the past 5 years. The facility has an emergency response plan which is coordinated with the Atlanta-Fulton County Emergency Manag ement Agency/Fulton County Local Emergency Planning Committee (LEPC) and the Fire Department (FD). The R. M. Clayton WRC is prepared to respond by assessing the hazard level of a release, and correcting or interrupting incidental leaks. The LEPC/FD will respond to substantial releases as well as any release that is identified as migrating off the R. M. Clayton WRC property. The LEPC/FD will notify the public if an imminent health threat is determined to exist. To help prevent accidental releases of chlorine or methane, the R. M. Clayton WRC has developed a Prevention Program (Program 2). The Prevention Program includes the following key elements: 7 safety information and equipment (such as automatic shutoffs, chlorine and methane detectors) 7 hazard review of equipment and procedures 7 safe and standard operating procedures 7 operator training 7 preventive maintenance program 7 compliance auditing program 7 incident investigation program The R. M. Clayton WRC has identified oppo rtunities to increase the safety of the facility, the public, and the environment. The primary safety enhancement will be accomplished by the installation of the UV disinfection system. Additionally, the facility plans to implement other improvements including, but not limited to: detection system upgrades, lightning protection upgrades, and continuing enhancement of the inspection and response planning procedures. |