City of Bogalusa Waste Water Treatment Plant - Executive Summary |
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The City of Bogalusa Waste Water Treatment Plant is committed to a continuous effort to improve safety at the facility. Currently, construction is underway to provide state of the art technology for chemical release containment. While construction is proceeding, all current methods of safe handling of hazardous chemicals are constantly being revised. The City of Bogalusa is committed to protecting its citizens while at the same time providing services needed to handle the sanitary needs of the City. The City's waste water treatment plant is located in a low lying area behind and below the Bogalusa City Hall Complex. The waste water treatment plant collects all discharged waste water, including sewerage, and then using chemicals and biological substances removes sufficient contaminants to render the discharge clean enough to be returned to natural waterways. The chemicals used in this process are chlorine and sulfur dioxide. Both chemicals are on the EPA's list of toxic chemic als. The chemicals are stored in one ton and 150 pound cylinders. A normal quantity stored at the facility approximates 9,000 pounds of chlorine and 6,000 pounds of sulfur dioxide. The Risk Management Program requires that two scenario's be developed to demonstrate the results of any accidental release of any regulated substances used in a process. The first is a worst-case scenario. This scenario assumes that the largest vessel containing either chlorine or sulfur dioxide ruptures and the entire content of the vessel is released in a 10 minute period. Since the treatment plant's largest vessel is a one ton cylinder, it is estimated that 200 pounds of chlorine would be released per minute. The model used for determining the toxic endpoint is EPA's RMP Guidance for Waste Water Treatment Plants Reference Tables or Equations. Using this model, the calculated distance to the toxic endpoint, with a wind speed of 1.5 meters per second, an atmospheric stability class of F, and a to pography description of rural, is 3.0 miles. Public receptors within that distance include the City Hall Complex, commercial buildings, private residences, schools, recreation area, and a hospital. The second scenario is an alternative release. This is a more realistic scenario for an accidental release. The results from this scenario are the same for both chlorine and sulfur dioxide. The same model was used to determine the distance to a toxic endpoint. In this scenario, we said a faulty valve on a 150 pound cylinder releases the entire contents in a 10 minute period. The model for this scenario uses a wind speed of 3 meters per second, and atmospheric stability class D, and topography description of rural. The distance to the toxic endpoint for both chlorine and sulfur dioxide is .2 miles. Public receptors within that distance include the City Hall Complex, commercial buildings, and private residences. Currently, there are no mitigating measures in place except that chlori ne and sulfur dioxide vapors are heavier than air, and since the waste water treatment plant is located on terrain lower than the surrounding public receptors, the toxic endpoint may be less than the model indicates. The Bogalusa Waste Water Treatment Plant has a general accident release prevention program which consist of daily visual inspection of all vessels. Signs, identifying the hazardous chemicals, as well as a partial enclosure protect the vessels. All facility employees have been trained in the proper handling of chlorine and sulfur dioxide. The waste water facility has had no accidental releases of any EPA regulated chemicals in the last five years. The Bogalusa Waste Water Treatment Plant is included in the Bogalusa City Fire Department Emergency Response Program. The City Fire Department keeps repair kits for chlorine and sulfur dioxide one ton cylinders. A major release would be handled by the Fire Department. Small accidental releases would be handled by the emp loyees of the facility. Repair kits, PPE including SCBA are stored at the facility. There is also an automatic monitoring and alarm system engaged at the facility to provide early warning to any accidental release. As previously stated, a new containment area is currently under construction. The facility addition should be completed by November 1, 1999. The new system will incorporate a scrubber as well as a vacuum controlled environment and state of the art monitoring equipment. New safety training procedures, maintenance procedures, and emergency response procedures are currently being developed and should be complete and implemented by December 31, 1999. |