Foamex Milan Plant - Executive Summary |
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EXECUTIVE SUMMARY Accidental release prevention and emergency response policies At the Foamex International, Inc. Milan Plant in Milan, Tennessee, we handle toluene diisocyanate (TDI), which is considered hazardous and regulated by the EPA. The same properties that make TDI valuable for use at our facility also make it necessary to observe certain safety precautions in the handling of this substance. TDI is considered a toxic substance and associated safety precautions have been implemented to prevent unnecessary human exposure, to reduce the threat to our own personal health as well as our co-workers, and to reduce the threat to nearby members of our community. It is our policy to adhere to all applicable federal and state rules and regulations. We are committed to the safety of our employees and the public, and to the preservation of the environment, through the prevention of accidental releases of hazardous substances. Successful implementation of our accidental release prev ention program will help ensure that emergencies are unlikely and reduce the likelihood that emergency response procedures will be needed. Nevertheless, an emergency such as a fire, explosion, or toxic release of TDI is possible. We have emergency response procedures to help ensure that accidents will be mitigated properly without undue risk to the public, environment, employees, contractors, or other personnel within the plant. Description of the facility and the regulated substances handled The primary purpose of this facility is to produce polyurethane foam, which is sold to other facilities and used to produce furniture and a number of other products. TDI is one of the reactants required to produce our polyurethane foam. TDI is received by rail car and by tank truck, and is stored in five indoor storage tanks. The maximum quantity of TDI stored in rail cars and in storage tanks at our plant is about 500,000 pounds. The TDI is piped to a mix head where it is mixed with other reactants to produce a slab of polyurethane foam. The foam is conveyed to cutting stations where it is cut to the size and shape specified by our customers TDI is the only substance handled at our plant that is regulated by EPA's risk management program (RMP) rule. This substance is covered because the maximum quantity stored onsite exceed EPA's threshold quantity (TQ) of 10,000 pound for the substance. Offsite consequence analysis of release scenarios We performed an offsite consequence analysis (OCA) to estimate the potential for an accidental release to affect the public or the environment. The OCA consists of evaluating worst case release scenarios (WRSs) and alternative release scenarios (ARSs). We do not expect a worst case release scenario to ever occur. An ARS represents a release that might occur during the lifetime of a facility like ours. ARSs help us to work with the local emergency planning committee (LEPC) to improve the community emergency response plan. The m ain objective of performing the OCA is to determine the distance at which certain effects might occur to the public because of an accidental release (called the endpoint distance). The following effects could occur at the endpoint distance: ' Most people at the endpoint distance of a toxic substance release like TDI would be able to walk away from the exposure without any long-term health consequences, although some short-term consequences (e.g., strong eye or throat irritation) are likely. Some people who are particularly susceptible to the released substance could be incapacitated. Worst case release scenarios. Catastrophic failure of a TDI rail car, having a capacity of 200,000 lbs. TDI, would be a worst case release for a toxic substance because a TDI rail car is the largest outdoor TDI container on the plant. The TDI vendors limit the quantity of TDI loaded into a railcar to 192,000 lbs. maximum to allow space for thermal expansion during possible heating of the TDI. During cold weather, we pre-heat the TDI to a maximum temperature of 95 0F to facilitate unloading and prevent TDI solidification. During hot weather, the TDI temperature could reach the maximum ambient temperature of 100 0F. Because a release at a higher temperature will result in the greatest endpoint distance, we assumed the release would occur at 100 0F. We also assumed that the entire contents of the railcar would be released as a liquid, form a pool that would spread to cover an area of approximately 80,000 ft2 with a depth of about 0.4 inches (1 cm), and evaporate to form a toxic cloud that would disperse downwind. Refined dispersion modeling predicts a distance of 560 ft. from the rail car to the TDI toxic endpoint concentration of 0.98 ppm (0.007 mg/L). Alternate Release Scenarios. Rupture of the transfer line from the railcar unloading pump to the TDI storage tank would release TDI to the ground at the standard pump rate of 950 lb/min. We assumed that the release would co ntinue for the 5 minutes required for an employee to stop the pump using remote emergency shutdown controls. The resulting pool would spread to cover an area of approximately 1,900 ft2 with a depth of 0.4 inches and evaporate to form a toxic cloud that would disperse downwind. Refined dispersion modeling predicts a distance of less than 33 ft. from the pool to the TDI toxic endpoint concentration of 0.98 ppm. The general accidental release prevention program and specific prevention steps The plant has implemented programs and procedures that comply with EPA's Level 2 Accidental Release Prevention Program Rule. Our facility qualifies for Level 2 coverage because (1) our worst case release scenario for TDI can impact persons across the property boundary of the nearest public receptor, and (2) TDI is not a substance covered by OSHA's process safety management standard (PSM). Our accidental release program is designed to systematically accomplish the following functions: - Cont rol the creation and retention of safety information regarding the regulated substance, processes and equipment - Conduct hazard reviews to identify, evaluate, and control process hazards associated with the regulated substance, processes, and procedures - Create, maintain, and evaluate operating procedures for activities within or near processes that use the regulated substance - Provide training for personnel who operate covered processes so that they safely perform their jobs - Monitor and control maintenance activities that can affect the mechanical integrity of equipment used in covered processes - Confirm through compliance audits that RMP practices at the plant are consistent with our written programs and that the programs are adequate to address all of the requirements of the RMP rule - Ensure that process incidents, particularly those of catastrophic magnitude or potential, are thoroughly investigated using our incident investigation procedures and that relevant findings are c ommunicated throughout the company to help prevent recurrence The TDI processes on our plant have hazards that must be managed to ensure continued safe operation. The prevention program outlined above is applied to the TDI processes. Collectively, these prevention program activities help prevent potential accidental releases that could be caused by equipment failures, human errors, and by management system failures. In addition to the accidental release prevention program, our plant has safety features on many units to help (1) contain or control a release, (2) quickly detect a release, and (3) reduce the consequences of or mitigate a release. The following types of safety features are used in various units of the TDI processes: Release detection - Process alarms - Video monitors Release Containment/Control - TDI storage tanks piped to overflow to other vessels - Curbing or dikes to contain TDI liquid releases - TDI storage tanks located inside an e nclosed building - Automated shutdown systems for critical process parameters (e.g., high level, high pressure) - Pressure/vacuum relief devices on vessels to prevent rupture or collapse - Remote shutdown of unloading and transfer pumps - Magnetic drive TDI centrifugal pumps without seals - Valves to permit isolation of the process - TDI railcar inner tank surrounded by an outer shell filled with insulation - TDI railcars are unloaded through a nozzle in the top of the tank Release Mitigation - Fire suppression and extinguishing systems - Trained emergency response personnel - Personal protective equipment (e.g., protective clothing, self-contained breathing apparatus, breathing air stations) Five-year accident history We have had no releases of TDI or in the last 5 years that resulted in deaths, injuries, or significant property damage on site, or known deaths, injuries, evacuations, sheltering-in-place, property damage, or environmental damage off site. We have had 1 small releases of TDI over the past 5 years. This release either occurred inside an operating building and was too small to result in injuries or significant damage. Emergency Response Program Our emergency response program is based on the requirements in OSHA's emergency action and fire prevention plan regulation, OSHA's hazardous waste and emergency operations regulation, and EPA's emergency response program requirements in its RMP rule. Our program consists of procedures for responding to a release of TDI . The procedures address all aspects of emergency response, including proper first aid and medical treatment for exposures, evacuation plans and accounting for personnel after an evacuation, notification of local emergency response agencies and the public if a release occurs, and post-incident cleanup and decontamination requirements. In addition, the plant has procedures that address maintenance, inspection and testing of emergency response equipment. Employees receive training i n these procedures as necessary to perform their specific emergency response duties. The emergency response program is updated when necessary, based on modifications made to plant processes or other facilities, by using management of change procedures. Personnel affected by changes in the program are informed and or trained on those changes. The overall emergency response program for the plant is coordinated with the LEPC. This coordination includes participation in periodic meeting of the committee, which includes local emergency response officials, local government officials, and other industry representatives. The plant has around-the-clock communications capability with the appropriate LEPC officials and emergency response organizations such as the fire department. This provides a means of notifying the public of an incident, if necessary, as well as facilitating quick response to an incident. The plant also conducts periodic emergency drills that involve the LEPC and emerge ncy response organizations. Planned changes to improve safety We strive to improve the safety of our plant TDI processes through periodic safety reviews and a program of soliciting safety suggestions from employees. Our hazard review and incident investigation programs are especially designed to identify needed process safety improvements, some of which result in changes to the processes. The following changes are currently planned for implementation: ' Upgrade inspections and tests of selected equipment and instrumentation designed to prevent TDI releases ' Revise operating procedures to resolve findings from the latest TDI process hazard review |