McCook Metals L.L.C. - Executive Summary |
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EXECUTIVE SUMMARY Accident Release Prevention Program and Emergency Response Policy It is the policy of the McCook Metals, L.L.C. (McCook Metals) facility management to implement the requirements of this Risk Management Program (RMP) in accordance with the USEPA regulations under 40 CFR Part 68 and with the corresponding regulations under OSHA's Process Safety Management (PSM) program. The objective is to minimize the risk of a release of a hazardous material and if a release occurs, to minimize the potential impact to McCook Metals employees, the surrounding public and the environment. This objective will be accomplished by utilizing general good operating procedures, providing appropriate training to all employees, and coordinating response activities, as necessary, with the local emergency response providers. McCook Metals' management is committed to providing all the resources necessary to implement this policy. Facility Description McCook Metals manufactures aluminum coil sto ck and plate stock from virgin and scrap aluminum and various hardening alloys. The facility has various melting and holding furnaces, hot and cold rolling mills, annealing and soaking furnaces, and ancillary equipment. These operations cast ingots and roll and cut the aluminum into the desired product. Figure 1 shows the site location and Figure 2 shows the facility layout. One chemical, Chlorine, is utilized at the facility in sufficient quantities to be subject to the requirements of 40 CFR Part 68, RMP. Chlorine is part of the mixed gas used for aluminum fluxing purposes. Chlorine is delivered in one-ton cylinders, which are connected to the central chlorine system at the east end of the Cast House. Worst-Case and Alternative-Case Release Scenarios RMP regulations require that each facility complete worst-case and alternative-case release scenarios. USEPA has defined a worst-case toxic release as the release of the entire contents of the largest vessel that contains a re gulated substance in a 10-minute period. This release rate is then evaluated using modeling techniques and/or reference tables to define the distance to a specified endpoint (concentration or overpressure). The distance to the endpoint is affected by several factors including molecular weight, volatility, heat of combustion, and physical setting (urban or rural). The alternative release scenario for each covered process must be one that is more likely to occur than the worst-case scenario and that reaches an endpoint off site, unless no such scenario exists. The alternative release scenario is evaluated using the same techniques as the worst-case scenario to define the distance to the specified endpoint. Under 40 CFR 68 Subpart B '68.22(e), the RMP rule identifies surface roughness as a parameter to be used in the hazard assessment to determine the physical setting of the site, urban or rural. "Urban means there are many obstacles in the immediate area; obstacles include building s or trees. Rural means there are no buildings in the immediate area and the terrain is generally flat and unobstructed." Due to the presence of trees, and other structures in the immediate vicinity of the McCook Metals facility, an urban dispersion environment was assumed. Chlorine The worst-case release scenario for chlorine is defined as a release of all the contents of one chlorine storage tank in a 10-minute period (per EPA guidelines). This translates to a release of 2,000 pounds of Chlorine in 10 minutes or 200 lbs/min. Other assumptions included in the worst-case assessment are: the Chlorine is a liquefied gas; the release does not take place indoors; the nearfield dispersion environment is characterized as urban; 10-minute averaging period; the wind speed is 1.5 meters/sec and the atmospheric stability is classified as F (stable). The results of the worst-case assessment for Chlorine show that the plume must travel 1.3 miles (2.1 kilometers) before dispersing to the endp oint concentration of 0.0087 mg/L. Figure 3 shows the worst-case release zone. The selected alternative release scenario for the Chlorine system is a release from a broken line in the plant containing mixed gas. This scenario is based on the most recent incident involving the mixed gas system. It was determined that the release rate of chlorine is 15 pounds per hour per cylinder. There are two cylinders connected to the system at all times. This yields a release rate of 30 pounds of chlorine per hour. EPA's computer model, RMP*Comp Version 1.06, was used to calculate the endpoint distance for this alternative release scenario using typical meteorological conditions (3 m/s wind speed, D atmospheric stability, 50% relative humidity). It is estimated that the maximum response time to this leak would be 60 minutes. Based on the release rate of 30 pounds per hour, the total amount released is 30 pounds. Other assumptions include no active or passive mitigation measures are curren tly in place and an urban dispersion environment in the nearfield. The results of the alternative release scenario for a Chlorine release indicates that the endpoint concentration of 0.0087 mg/L is reached at 0.1 miles (160 meters) from the release point. Figure 4 shows the alternate-case release zone. General Accidental Release Prevention Program and Chemical Specific Prevention Steps The McCook Metals facility is governed by a set of OSHA and USEPA regulations that require planning and facility activities intended to prevent a release of hazardous material, or if a release inadvertently occurs, to minimize the consequences of a release to the employees of the facility, the surrounding public and to the environment. These regulations include: 7 40 CFR Part 68, Accidental Release Prevention 7 40 CFR Part 112, Spill Prevention, Control and Countermeasure 7 40 CFR Part 264, Hazardous Waste Contingency Plan 7 29 CFR Part 119, Process Safety Management The key concepts in McCook Me tals' release prevention program are employee participation, appropriate design and maintenance of equipment, and appropriate training of all employees. Employee participation in the release prevention program is encouraged and supported by McCook Metals management. McCook Metals management and hourly personnel are members of employee teams organized to generate documentation and to provide ongoing PSM support. Key personnel are responsible for conducting and implementing the findings from the Process Hazard Analysis (PHA) for the Chlorine system. McCook Metals employees are also members of the facility emergency response team. McCook Metals has an emergency response plan in place and sufficient equipment on site for an initial response to most Chlorine releases. McCook Metals policy is to construct all new equipment, systems, and facilities to ensure the appropriate safety and release prevention systems are included from the beginning of each project. McCook Metals maintains a pr ogram of maintenance activities to ensure that key systems are maintained appropriately to minimize the risk of a release. McCook Metals is committed to providing appropriate training to all employees regarding safety procedures. Each new employee is provided comprehensive safety training during his or her initial orientation for the facility. In addition, McCook Metals conducts refresher training at least every three years, but may be held more frequently, if the process operators or management team deem it necessary. Additional training is provided to maintenance personnel for the systems they are responsible for. Members of McCook Metals' emergency response team receive annual training to ensure that response actions are promptly and safely completed. Five Year Accident History McCook Metals has had three releases of Chlorine from the McCook, Illinois facility within the last five years; the largest release was 7,600 pounds over a 152-hour period. No one offsite was injured and no residences or businesses were evacuated. This release happened in February 1994 and actions have been taken to eliminate a release of this magnitude from happening again. Emergency Response Program McCook Metals has personnel trained in emergency response at the facility 24 hours per day, seven days per week. These personnel receive annual training on emergency procedures and response techniques. Emergency response is also coordinated with the LEPC. Planned Changes to Improve Safety McCook Metals completes a thorough review of the Chlorine system each time a design change is implemented. McCook Metals is committed to using these methods to identify and implement ways to improve the safety of the system. The PSM committee is involved with any modification of the Standard Operating Procedures (SOPs), Process and Instrumentation Diagrams (P&IDs), and the Emergency Response Plan. |