Calaveras Co. La Contenta WWTP - Executive Summary |
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FEDERALLY MANDATED RMP SUBMISSION EXECUTIVE SUMMARY 1. Accidental Release Prevention and Emergency Response Policies The County of Calaveras uses chlorine at its La Contenta Wastewater Treatment Plant (LaC-WWTP). The chlorine is stored in the Chemical Building is liquified chorine gas under pressure and is considered a hazardous material; Chlorine gas is also a regulated substance under the California Accidental Release Program (CalARP). Calaveras County Environmental Health recognized the LaC-WWTP as a Stationary Source under the CalARP regulations and requested this Risk Management Plan (RMP). The County of Calaveras policy is to adhere to all applicable Federal and State of California rules and regulations. Safety depends upon proper construction design and safety features of the facility, accurate operating and emergency procedures, and effective training of personnel. 2. Stationary Source and Regulated Substances LaC-WWTP is a 400,000 GPD facility that treats domestic se wage from 485 residences and businesses in the La Contenta subdivisions near Valley Springs. Chlorine gas is used to disinfect the treated wastewater before it is sent to the golf course for summer irrigation. The Chemical Building at LaC-WWTP is an enclosed structure located at 1525 Campbell Court in Valley Springs, California. As a Stationary Source, there is one Federally regulated substance in one regulated process. The regulated process for chlorine includes: gas container unloading and storage, a metering/mixing device, and an gas-in-solution injector. When chlorine gas is dissolved in water, it is no longer a regulated substance in the CalARP. The chlorine gas is trucked to the facility in one-ton containers. There are two one-ton containers of chlorine stored in the Chemical Building. 3a. Worst Case Release Scenario The Worst Case release scenario for interconnected equipment must consider the largest quantity of a regulated substance handled on site in a single vesse l at any time, taking into account administrative controls on the vessels contents and usage as per the CCR Title 19 Division 2 Chapter 4.5 Article 2 Section 2750.3(b). The 2,000-lb container is considered the largest vessel of chlorine. The one-ton container is, at most, filled with 2,000 lb of liquid chlorine. The Worst Case release scenario for the one-ton container is the release of the entire capacity at a rate of 110 lbs per minute for a ten-minute duration. The standard release rate of 200 lbs per minute has been decreased due to the chlorine container being inside a building. The distance to the 3 ppm (0.0087 mg/L) would extend beyond the boundaries of the stationary source. 3b. Alternative Release Scenario The Alternative Release scenario for the one-ton container is complete failure and separation of a quarter-inch fuse plug in the end of the container. All 2,000 lbs of chlorine are assumed to flash to vapor. The distance to the end point of 3 ppm (0.0087 mg/L) for the chlorine release would extend beyond the boundaries of the stationary source. 3c. Administrative Controls Administrative controls to limit the distances for each reported scenario exist to restrict, to a minimum, the amount of chlorine lost from a one-ton container if an accidental release were to occur; and preferably to not have a release occur. These administrative controls are inherent in the operational procedures for the regulated substances processes and the training provided to the operators. Administrative controls are also in place for the regulated processes. 3d. Mitigation Measures Mitigation measures to limit the distances for each reported scenario exist to restrict the amount of the regulated substances released to a minimum, if a release were to occur; and preferably to not have a release occur. The mitigation measures are based on the design, inspection, testing, and maintenance of the regulated processes and their related equipment and components. 4. Gener al Accidental Release Prevention Program and Chemical Specific Prevention Steps The facility complies with all applicable Federal and State codes and regulations. There are safety meetings and safety training. The Process Safety Management (PSM) program implemented at the facility for the regulated processes and their related activities and equipment represents the facilitys main active commitments to an accidental release prevention program. 5. Five Year Accident History There have been no accidental releases of regulated substances within the last five years. 6. Emergency Response Program The Emergency Response Program is based upon the alerting of personnel at the facility to evacuate or shelter-in-place and await the arrival of responders from the local area responder at the assembly location if a release occurs that causes the evacuation or the shelter-in-place to be initiated. 7. Planned Changes To Improve Safety Current applicable codes and regulations are reviewed as part of the Process Hazard Analysis element of the Process Safety Management (PSM) program to determine if commitments need to be made to achieve increased operational safety for the regulated processes. These commitments address prevention and mitigation measures for accidental releases of the regulated substances. The completion schedules for these commitments are included in the PSM. |