City of Alvin Wastewater Treatment Plant - Executive Summary |
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EXECUTIVE SUMMARY 1. Accidental release prevention and emergency response policies This is a wastewater treatment facility in the disinfection process, the handling of chlorine and sulfur dioxide is required (chlorine and sulfur dioxide are considered hazardous by the EPA). The same properties that make them a valuable commodity also make it necessary to observe certain safety precautions in handling of these chemicals to prevent unnecessary human exposure, to reduce the threat to our own personal health as well as that of our co-workers, and to reduce the threat to nearby members of the community. It is our policy to adhere to all applicable Federal and state rules and regulation. Safety depends upon the manner in which we handle chlorine and sulfur dioxide, the safety devices inherent in the design of this facility, the safe handling procedures that we use, and the training of our personnel. Our emergency response program is based on recommendations from the Chlorine Institute including procedures for the notification of all necessary agencies and potentially affected neighbors. 2. The stationary source and regulated substance handled The primary purpose of this facility is to treat wastewater for return into the environment, in the treatment chlorine gas is used for the purpose of effluent disinfection, and sulfur dioxide is used to neutralize the chlorine residual. The chlorine and sulfur dioxide are stored in Department of Transportation (DOT) approved containers. Both chemicals are injected into the water through equipment which meets ASTM Standards. Access to the site is restricted to authorized facility employees, authorized management personnel and authorized contractors. The regulated substances handled at this facility are chlorine and sulfur dioxide. The total inventory of chlorine is 8000 pounds and total inventory of sulfur dioxide is 8000 pounds. 3. The worst-case release scenarios and the alternative release scenarios Worst-Case Scena rio (chlorine) - Failure of a one ton cylinder of chlorine would release 2,000 pounds of chlorine. It is assumed the entire contents are released as vapor, which is heavier than air. The distance to the endpoint of 0.0087 mg/l (3ppm) is 1.3 miles, as determined by the RMP*COMP modeling program. Worst-Case Scenario (sulfur dioxide) - Failure of a one ton cylinder of sulfur dioxide would release 2,000 pounds of sulfur dioxide. It is assumed the entire contents are released as vapor, which is heavier than air. The distance to the endpoint of 0.0087 mg/l (3ppm) is 1.3 miles, as determined by the RMP*COMP modeling program. Alternative Release Scenario (chlorine)- A one ton cylinder of chlorine is puncture with contents being released as a vapor. The endpoint of 0.0087 mg/l is 0.3 miles, as determined by the RMP*COMP modeling program. Alternative Release Scenario (sulfur dioxide)- A one ton cylinder of sulfur dioxide is puncture with contents being released as a vapor. The endpoint of 0.0087 mg/l is 0.2 miles, as determined by the RMP*COMP modeling program. 4. General accidental release prevention program and the specific prevention steps This facility complies with all Federal and state regulation. This facility is also operated in accordance with recommendations from the Chlorine Institute, and Texas A&M's Engineering Extension Services. All equipment is regularly serviced by equipment suppliers authorized personnel along with the continued training of all personnel that work with the equipment. 5. Five-year accident history This facility has had no accidental release of chlorine or sulfur dioxide in the past five years. 6. The emergency response program This facility's emergency response program is in conjunction with the Brazoria County Local Emergency Planning Committee and the Alvin Fire Department. It involves the notification of all agencies involved and notification of all potentially affected neighbors. 7. Planned changes to improve safety O ptions are currently being researched for alternatives to using chlorine gas in the disinfection of wastewater effluents. |