City of Auburn Water Purification Plant - Executive Summary |
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ACCIDENTAL RELEASE PRVENTION AND EMERGENCY RESPONSE POLICIES AT THE FACILITY At the Auburn Water Filter Plant, we handle chlorine, which EPA considers hazardous. Certain safety precautions must be followed in order to allow for a safe work environment, preventing unnecessary exposure, and reducing threat to members of the community. The City adheres to all state and federal rules and regulations that are applicable to this facility. A safe environment at the plant is dependent on the manner in which chlorine is handled, the safety devices included in the facility, safe handling procedures and ongoing safety training of filter plant personnel. THE FACILITY AND THE REGULATED SUBSTANCES HANDLED The Auburn Water Filter Plant is located at the corner of Swift Street and Pulsifer Drive in the City of Auburn. The slow-sand filtration plant was constructed in 1919. The City presently has two filtration plants in use: a slow-sand plant and a rapid-sand plant. The plant contains four beds with a total capacity of about 8 mgd. The water level is generally about 7 feet in the beds. The beds consist of about 3 feet of sand supported by 12 inches of gravel. Prior to rapid sand filtration, the raw water passes through an upflow clarifier for suspended solids removal. Powdered alum is the primary coagulant and is fed via solution form to a mixing basin in the center of the clarifier. The alum dose is controlled manually by the plant operators based on the raw water flow and characteristics. The sludge accumulated at the bottom of the clarifier is drained to a lagoon where the supernatant is decanted to the Owasco Lake outlet. Sludge is removed from the bottom of the lagoon on an as needed basis. Disinfection is accomplished by a vacuum gas chlorination system. Chlorine can be injected at the plant influent and filter effluent (prior to the clearwell). The chlorine residual of the water prior to entering the distribution system is measured by an online chlorine residual analyzer. The chlorine feed rate is manually adjusted to maintain a free chlorine residual of approximately 1.5 mg/l entering the distribution system. The City has the capability to feed sodium hypochlorite in the event that the gas chlorinators become inoperable. The maximum amount of chlorine stored at this facility is 6,000 lbs. (3 Ton cylinders). THE WORSE-CASE RELEASE SCENARIO(S) AND THE ALTERNATIVE RELEASE SCENARIO(S) 7 Worse-case scenario. A gas release would release 2,000 lbs. of chlorine. The distance to the endpoint is 1.30 miles. 7 Alternative scenario. A pipe leak liberating chlorine gas. The distance to the endpoint for the alternative scenario is 1.30 miles. THE GENERAL ACCIDENTAL RELEASE PREVENTION PROGRAM AND CHEMICAL SPECIFIC PREVENTION STEPS The City of Auburn Water Filter Plant complies New York State codes and regulations that are applicable. Design and construction of the facility was in accordance with the rules and guidelines of the New York State Health Department, w hich inspects annually. The City has in place a Water Supply Emergency Action Plan, which includes a section on "Chlorine Gas Leak Emergency Procedure." The Auburn Fire Department also has in place a policy entitled "Hazardous Materials Response Plan." THE FIVE-YEAR ACCIDENT HISTORY There have been no accidents in the past five years. THE EMERGENCY RESPONSE PROGRAM The Water Filter Plant has an emergency response program in place entitled "Water Supply Emergency Plan." Also, the Auburn Fire Department has in place a policy entitled "Hazardous Materials Response Plan," created in conjunction with the Public Works Department and the Water Filter Plant, specifically to deal with chlorine emergencies. PLANNED CHANGES TO IMPROVE SAFETY The Auburn Water Filter Plant was constructed in 1919. An engineering study is currently underway for the purpose of EPA regulatory compliance updates. This review includes safety plans, procedures and equipment. It has been identified that for safety purp oses, the City will include in its plans to switch from gaseous chlorine to liquid hypochlorite as a disinfectant. It is anticipated that these improvements will commence within the next nine months and be completed within the next 24 months, mitigating any hazards associated with gaseous chlorine that have been identified. |