City of Panama City Beach Water Treatment Plant #1 - Executive Summary |
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CITY OF PANAMA CITY BEACH WATER TREATMENT PLANT EXECUTIVE SUMMARY The City of Panama City Beach ("The City of PCB") has been requested to develop, implement, and submit to the United States Environmental Protection Agency a detailed Risk Management Plan for Water Treatment Plant One by June 21, 1999. The following is an executive summary on the components and progress of the plan. a. The City of Panama City Beach accidental release prevention policy involves a unified approach that integrates technologies, procedures, organizations, and management practices. The City emergency response policy utilizes the emergency response services available within the City and County and is in compliance with the EPA Emergency Response Program. b. The City currently supplies treated water to retail customers between Hathaway Bridge and Phillips Inlet. The City of PCB Water Plant One chlorination system has been installed to provide water distribution for wells supplying the western service a rea. The chlorine is handled in two one-ton containers. This facility is normally unmanned. Water treatment operators visit the facility daily and will respond to any trouble alarms if such a need arises. c. The City has two chlorine release scenarios, identified as "worst case release" and "alternative release". The worst case release scenario is catastrophic failure and could be caused by corrosion, impact or construction defects. It involves a failure of a one-ton chlorine container. We referred to data collected by AWWA Research Foundation and American Water Works Association to determine the distance traveled by the chlorine released before its concentration decreases to the "toxic endpoints". Atmospheric dispersion modeling used a direct release with a discharge rate of 200 lb/minute for 10 minutes. The toxic endpoint distance was calculated to be 2.6 miles. The residential population potentially affected within a circle with a 2.6 mile radius corresponding to the toxic e ndpoint was estimated to be 2,520. The other scenario is defined as a more likely to occur situation and could be caused by tubing failure, bad connection, or valve failure resulting in the release of gas. This scenario was modeled as a release from a horizontal cylindrical tank with the release occurring through a short pipe or valve in the top of the tank. The maximum average sustained release rate was 10.5 lb/minute for a 60 minute duration. The toxic endpoint distance was .48 miles. The residential population potentially affected within a circle with a 2.6 mile radius corresponding to the toxic endpoint was estimated to be 465. Both scenarios used an ambient temperature of 77 degrees Fahrenheit as required by regulations. Active mitigation measures presently applied are the use of chlorine vacuum piping combined with a loss of vacuum alarm and a permanently installed and operative chlorine leak detector. d. The general accidental release prevention program consists of the following: High level of training of water plant operators and fire department personnel Preventive maintenance programs Use of appropriate safety equipment Use of accurate and effective operating procedures Implementation of an auditing and inspection program Chemical-specific prevention steps when connecting or disconnecting chlorine cylinders require that at least two employees must be present, each wearing a self-contained breathing apparatus with a full air cylinder. e. No accidental releases of chlorine have occurred at this facility in the past five years. f. The Water Plant has an emergency response plan coordinated by the City of Panama City Beach Fire Department. g. Planned changes to improve safety will be to provide continuing training and accident drills in cooperation with the Fire Department. |