Montana Power Company - Executive Summary |
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1.1 Regulated Substances Montana Power Company (MPC) operates a coal-fired electrical generation plant (Units 1-4) in Colstrip, Montana. An extensive review of the existing processes at MPC has identified liquid petroleum gas (LPG) and chlorine as the only chemicals above the threshold quantities listed in the Code of Federal Regulations (CFR), Title 40, Part 68 and, therefore, subject to a Risk Management Plan (RMP). On April 27, 1999, the US Court of Appeals granted a stay on the RMP rule as it applies propane processes. EPA plans on increasing the threshold quantity for propane from 10,000 lbs to 67,000 lbs (approximately 18,000 gallons). Facilities will not have to file a RMP for a propane process until a future date, yet to be determined by EPA. This RMP submittal will only address the chlorine processes; if necessary, a future update to this submittal will address the propane process. Chlorine is used for microbiological control of the circulating water and the raw water syste m on Units 1 and 2 and Units 3 and 4. By virtue of the toxicity of chlorine, it is necessary to observe certain safety precautions in handling chlorine to prevent unnecessary human exposure, to reduce the risk to personal health and the health of our co-workers, and to reduce the risk to nearby members of the community. MPC is strongly committed to protecting the health and safety of their employees, the public, and nearby members of the community. Safety at MPC depends upon the manner in which chlorine is handled as well as on the various safety devices incorporated into the design of the equipment. Furthermore, comprehensive training received by MPC employees adds to the inherent safety of the facility. 1.2 The Worst Case Release Scenario(s) and the Alternative Release Scenario(s) Units 1 and 2 have six (6) chlorine (one ton each) cylinders stored on site, and Units 3 and 4 have twelve (12) chlorine cylinders (one ton each) stored on site at a location separate from the cylinders used for Units 1 and 2. The single largest vessel of 2,000 lbs was used to model the worst case and alternate release scenarios. The chlorine cylinders are stored inside an enclosed building and passive mitigation was used in the modeling. 1.3 The General Accidental Release Prevention Program and the Chemical-Specific Prevention Steps MPC has taken the necessary steps to comply with the accidental release prevention requirements set out in 40 CFR Part 68. The chlorine process is subject to OSHA Process Safety Management (PSM) regulations which parallel the RMP requirements except for the need for an analysis of offsite impacts. MPC has previously prepared a PSM plan for the chlorine used on-site. 1.4 Five Year Accident History MPC has an excellent record of preventing accidental releases over the last five years. No recordable accidental releases on the chlorine processes have occurred during this period. 1.5 Emergency Response Plan MPC has a written emergency response plan to deal with the accidental release of chlorine. The plan includes all aspects of emergency response including adequate first aid and medical treatment, evacuation, and communication with the local fire department and the public. To ensure proper functioning, the emergency response equipment is regularly inspected and serviced. In addition, the plan is promptly updated to reflect any pertinent changes taking place within the processes that would require a modified emergency response. |