WATER POLLUTION CONTROL- JOSHUA STREET PLANT - Executive Summary |
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CHAPTER 1- EXECUTIVE SUMMARY The Water Pollution Control Risk Management Plan for Safe Chlorine Handling involves a unified approach that integrates technologies, procedures, and management practices to monitor potential chlorine hazards and minimize the risk of accidental chlorine releases. All applicable procedures of 40CFR 68.170 are addressed in the plan, which seeks to provide for employee safety, public health, and response agency interaction. The Joshua Street Water Pollution Control Plant utilizes chlorine to disinfect the effluent flow before sending it to the Flint River. The treatment plant services the residents of the City of Albany, surrounding areas, and a large industrial base comprised of a wide range of manufacturing. The chlorination process includes (liquid) chlorine cylinders, chlorination equipment, an instrument room, electrical equipment, and process specific safety equipment. For each chlorination process, accidental release modeling was performed for the respective area to determine potential consequences associated with operating failures resulting in accidental chlorine release. The first "worst case " scenario, defined by EPA, states that "the owner or operator shall assume that the ... maximum quantity in the largest vessel... is released as a gas over release scenario". For the Joshua Street Plant an incident history review was performed to identify the most likely case scenario. In each case, atmospheric dispersion modeling was performed to determine the distance traveled by the chlorine released before its concentration decreases to a theoretical "toxic endpoint." This is defined by the American Industrial Hygiene Association as "the maximum airborne concentration below which it is believed that nearly all individuals could be exposed for up to one hour without experiencing or developing life-threatening health effects." The residential population within a perimeter corresponding to the toxic endpoint distance was defined to estimate the population potentially affected. The worst case release scenario for the Joshua Street Plant involves the failure of a one-ton cylinder yielding a cumulative release of 2,000 lbs. of chlorine. When atmospheric dispersion modeling for this implausible scenario was performed, using the EPA guidance document, a distance to toxic endpoint of 3.1 miles was obtained. The alternative release (more likely) scenario for the chlorination process involves the mechanical failure of one flexible manifold connection (pigtail) allowing the accidental release of a one ton cylinder of chlorine over a one hour period. Similar atmospheric modeling per EPA guidance yields a more likely figure of .38 miles affected radius under normal atmospheric conditions at each site. Within these perimeters, the Joshua Street Plant identified ____receptors. In support of the probability that a worst case accidental release will not occur, a review of process history indicates that no reportable a ccidental releases greater than a 10 lb quantity have occurred within the past five years at the facility. The Water Pollution Control Risk Management Program includes the following key elements to mitigate the effects of potential chlorine release hazards: * Operator Training * Preventive Maintenance Program * Process specific safety equipment * Safe and effective standard operating procedures, written with operator participation * Hazard review of equipment and procedures * Auditing and inspection programs * Comprehensive Management Program Further, WPC has an active environmental, health and safety program with the following elements specifically supporting the safe handling of chlorine and the chlorination process: * Respiratory protection (SCBA) program * Chlorine detectors * Chemical right to know program * Personal protective equipment program The Joshua Street Treatment Plant has an emerg ency response plan, which has been coordinated with the City of Albany Fire Department and Dougherty County Emergency Services, both of whom are members of the Local Emergency Planning Committee (LEPC). Emergency response drills, drill evaluations, and facility tours are conducted annually, at which time emergency operation and response procedures are also reviewed. WPC takes a proactive approach to risk management and emergency response through continuous joint training sessions between WPC employees and local response agencies. These preventative measures will provide for the continuous improvement of communications and will maintain effective procedures for the safe handling of and timely emergency response to potential chlorine hazards. |