Matsunk Water Pollution Control Center - Executive Summary |
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The Matsunk Water Pollution Control Center is operated by the Upper Merion Municipal Utilities Authority. All employees on site are Upper Merion Township municipal employees. The chlorine system, used for effluent disinfection, is the plant's only process that is subject to the EPA Part 68 RMP Regulations. A maximum of 6 full one ton containers are stored on site, indoors. A maximum of 2 full containers are connected for service on-line at one time. The worst-case release scenario identified in the Hazard Assesment for the chlorine process is the release of the entire contents of a one ton container within 10 minutes, as required by EPA CFR 40 Part 68.25 regulations. According to Exhibit 4-4 in the EPA's RMP Guidance for Wastewater Treatment Plants, the down wind distance to the toxic endpoint (concentration of 3 ppm) for this scenario is 1.3 miles. For the alternative release scenario, a liquid chlorine release through a 0.344" vessel hole (fusible plug failure) was selected. According to Exhibit 4-12 in the EPA's RMP Guidance for Wastewater Treatment Plants, the down wind distance to the toxic endpoint (concentration of 3 ppm) for this scenario is 0.3 miles. The chlorine building enclosure should provide some temporary containment and mitigation of an indoor release, which should further reduce this estimated distance to the toxic endpoint. The chlorine building houses a maximum quantity of 12,000 pounds of chlorine in steel one ton containers. The chlorine building contains all necessary safety equipment for overall safe operations: chlorine detectors and alarms, automatic ventilation system, repair kits, and personal protective equipment (PPE). The Authority's policy is to operate a safe, well maintained chlorine process. Operators are trained and experienced in operating the chlorine process. The policy of the Authority is to utilize on-site and off-site emergency responders for an emergency response event, if necessary. Emergency response action s are coordinated with the local community response agencies. There have been no reportable accidental releases of chlorine at the Matsunk WPCC to date. The Authority is in the process of converting the chlorine gas feed system to a liquid sodium hypochlorite feed system. The risk reduction measures identified in the Hazard Review will not be required for the sodium hypochlorite feed system. However, procedural and documentation risk reduction measures will be implemented for the chlorine gas system for the time period that it remains in use. |