DIXIE PARK WWTP - Executive Summary |
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EXECUTIVE SUMMARY Dixie Park WWTP (The Facilities) The Martin County Environmental Services Division's accidental release prevention and emergency response policies, integrate technology, procedures and management practices to assure safety of it's employees, the community and the environment. In service to the community, the County has a history of adhering to proactive approaches for the prevention and emergency response of accidental releases of toxic substances. Current prevention and emergency response polices adhere to the Environmental Protection Agency's (EPA) Prevention Program and Emergency Response requiremen ts as set forth under the 40 CFR 68 regulations. The Facilities are located in Hobe Sound, Florida and utilize chlorine gas in the wastewater treatment process. The Facilities maintain a non-enclosed, chlorination area and chlorination distribution system on-site. Chlorine is delivered to the central area and stored on- site in cylinders containing 2,000 pounds of liquefied chlorine under pressure when full. The chlorine facility holds a maximum of seven (7) 2,000 pound cylinders. The Facilities have an outstanding performance history in conjunction with handling, storing, maintaining and operating of chlorine gas. No accidental releases have occurred since the system went into service in 1986 under Martin County's ownership. The wastewater treatment plant is manned 10 hours/day, seven (7) day/week. State certified operational personnel are trained in the safe handling, maintenance and operation of chlorine system s that comply with EPA 40 CFR 68 regulations. The chlorination system is designed utilizing latest technologies and industry specific design codes and standards. The current emergency response plans are documented and coordinated with the community emergency response officials through the Local Emergency Planning Committee (LEPC). Operational staff are trained according to these response plans. The EPA 40 CFR 68 requires offsite consequence analysis of two (2) release scenarios for toxic substances identified as "worst case release" and "alternative release." The "worst case release" is defined by EPA as "the owner/operator shall assume that the ... maximum quantity in the largest vessel ... is released as a gas over 10 minutes." For the worst case release, EPA specifies the parameters to use in calculating the distance the chlorine will travel to achieve its "toxic endpoint." The alternative release is defined as "more likely to occur than the worst case rele ase scenario", such as a pipe leak. Utilizing the EPA's RMP* COMP Model, a distance of 4.3 miles was calculated for the worst case release toxic endpoint and 0.30 miles for the alternative release. As per EPA regulations, the population is estimated within the circles defined by the radius' corresponding to the toxic endpoints. These population values are 37,221 for the worst case and 813 for the alternative release. It is noted that if an actual release did occur according to the alternative release scenario, the population at risk would be substantially less due to the plume of gas being more in the form of an elliptical pattern moving down wind of the point source rather than a circle centered on the point source. The use of chlorination within water treatment and wastewater treatment has yielded enormous benefits in this County related to preventing the spread of water borne diseases. Martin County, like virtually every modern treatme nt facility, understands the value and risks of this treatment procedure. Martin County has an exceptional track record of no accidental releases in its history and remains ever vigilant in its attention to safety regarding chlorine. Martin County supports this regulatory effort to inform the public in the general vicinity of any utility of the risks associated with accidental gaseous releases. Indeed, we support efforts to notify the public of such risks at all points of exposure including the production, delivery and site storage of chlorine gas. If you have questions on this matter, you may contact the offices of Martin County Environmental Services, 2203 S.E. Ocean Blvd., Stuart, Florida 34996, (561)221-1442. dwm/execsum.dix/99-122.1 |