Lewiston-Auburn Water Pollution Control Authority - Executive Summary |
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The Lewiston - Auburn Water Pollution Control Authority is submitting this Risk Management Plan in order to comply with the Federal Regulations for Chemical Accident Prevention Provisions (40 CFR 68). The Authority is subject to the rule due to Its use of one ton chlorine gas cylanders for disinfection of the treatment plant effluent (chlorine is also occasionally used to control process conditions). The Authority also may need to submit a plan for propane used at the Authority's compost facility. (Note the compost facility is located a number of miles away from the waste water treatment plant), but is not submitting a plan for propane based upon our understanding that the rule requiring these plans for propane has been stayed. The Authority also uses aqua ammonia, but does not store or use amounts above the threshold quantity as we understand them. The Authority has utilized chlorine gas for the purposes described above for well over 20 years without an accident off site, and onl y minor releases on site including one minor injury to a contractor working for the Authority as described in section 6 of this sumbmittal. Athough the individual received mediacal attention, he returned to work directly and suffered no demonstrative effects. In the summer of 1997 the Authority completed an upgrade of the treatment plant which included a thorough reworking of our chlorine system. The significant changes to the disinfection system can be summerized as follows: 1) the system is now computer controlled and flow paced, with dosage and chlorine residual readings having alarm points that will notify an operator on site or at home when values exceed preset ranges. 2) Pressure piping was eliminated from the system and a gas purge/evacuation valve added. This makes the system intrinsically much safer. The only remaining portion of the system which is under pressure is the cylinders themselves and the whips that connect the cylinders to the chlorinators. In the event of a loss of vaccum, the system will automatically shut down. 3) Gas monitors were added in the lower portion of the treatment facility where gas, if leaked, would be most likely to accumulate. Traditionally all of the Authority's employees (with the exception of the office manager) have been trained in chlorine safety, use of self contained breathing aparatus (SCBA) and protective clothing, emergency response, and use of the chlorine institute "B kit". Due to changing regulations, and the need to have responders trained to a higher level, the Authority has joined in a cooperative efflort with the Auburn Water District and the Lewiston Department of Public Works to develop a Hazardous Materials Response Team. Annual drills have been held and the team has been trained and equipped. The parties are still working to refine and clarify notification and call out proceedures as well as to continue to strengthen the team. We do believe that at this time we have significant capabilty devel oped that will be able to respond to a hazardous material release at our facility. Partially as a result of preparing this Risk Management Plan, the Authority notes that more formalized maintenance and system start up procedures, and documentation of when these are completed is needed. In addition, the Authority will continue to work on better defining which areas and how many people may need to be evacuated in Lewiston and Auburn if a significant release from our system were to occur and to move off of our site. |