Union Carbide South Charleston Plant - Executive Summary |
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UNION CARBIDE CORPORATION SOUTH CHARLESTON PLANT RISK MANAGEMENT PLAN EXECUTIVE SUMMARY 1 Accidental Release Prevention and Emergency Response Policies The Union Carbide South Charleston Plant is committed to operating and maintaining all of our processes in a safe and responsible manner. We have implemented a combination of accidental release prevention programs and emergency response planning programs to help ensure the safety of our employees and the public, as well as to protect the environment. These programs include both Union Carbides Responsible Care. requirements and governmental requirements, such as the Environmental Protection Agencys (EPA) Risk Management Program (RMP) rule and the Occupational Safety and Health Administrations (OSHA) Process Safety Management (PSM) standard. 2 STATIONARY SOURCE AND REGULATED SUBSTANCES The Union Carbide South Charleston Plant is a manufacturing facility that annually produces more than 500 different specialty chemicals and plastics in its various operating units. Most are intermediates used in other Union Carbide processes, or sold to customers who convert them into finished products. The RMP rule requires that if a facility, such as theSouth Charleston Plant, has a specific amount (threshold) or more of any one of 140 toxic and flammable chemicals, the facility must follow the RMP rule requirements. Union Carbide handles and stores threshold quantities of the following RMP-regulated toxic substances at the South Charleston Plant: Allyl Alcohol Ethylene Oxide Propylene Oxide Vinyl Acetate Monomer Crotonaldehyde 50% Formaldehyde Union Carbide handles and stores threshold quantities of the following RMP-regulated flammable substances at the South Charleston Plant: Vinyl Methyl Ether Dimethylamine Methylamine Acetaldehyde Vinyl Ethyl Ether 3 Key Offsite Consequence Analysis Scenarios EPAs RMP rule requires that we provide information about the worst-case release scenario(s) and alternative release scenar io(s) for our facility. The following are brief summaries of these hypothetical scenarios. Unless otherwise specified, no credit was taken for administrative controls or mitigation measures in evaluating the off-site impact of the scenarios. Chemical-specific steps to prevent these scenarios from occurring, and to mitigate their effects should they occur, are shown immediately after the scenario description. The plant's general accident prevention program is described in Section 4. A) Regulated Toxic Substances Worst-Case Release Scenario This scenario assumes an over-pressure and rupture of a storage tank, releasing 39,000 lbs. of allyl alcohol as a gas to the atmosphere. According to EPAs Off-Site Consequence Analysis (OCA) Guidance Table, this release could impact off-site public receptors. Specific steps to prevent this scenario from occurring, and to mitigate its effects should they occur, include: 7 Hose Hook-up Design: Transfer hose connections are designed to prevent connection to an incompatible material, which might cause an uncontrolled reaction in the tank. 7 Material Analysis: A certificate of analysis must be reviewed to confirm transfer of material to the allyl alcohol storage tank is allyl alcohol and not an incompatible material. 7 Fire Water Spray Monitors: Area fire water spray monitors can be used to help suppress allyl alcohol vapors. 7 Surveillance: Operators routinely monitor the process. Alternate-Case Release Scenario(s) Allyl Alcohol: This scenario assumes an uncontrolled reaction causes a process vessel to fail and release allyl alcohol as vapor to the atmosphere at a rate of 2300 lbs. per minute for 15 minutes. According to the OCA Guidance Table, this release could impact off-site public receptors. The following active mitigation measures are used in this analysis: 7 Emergency Shutdown System: The system is designed to shut down the process and activate cooling when the process reaches high pressure, high temperature, l ow liquid level, or inadequate amount of catalyst conditions. This scenario assumes that the emergency shutdown devices detect, shut down, and isolate the process, but the vessel failure (crack) continues to release material over a 15 minute period. In addition, specific steps to prevent this scenario from occurring, and to mitigate its effects should they occur, include: 7 Pressure Relief Device: This device is designed to relieve pressure at a predetermined set point and prevent over-pressure of the process vessel. 7 Deluge System: A water spray system is designed to help suppress allyl alcohol vapors. It can be manual or heat activated 7 Fire Water Spray Monitors: Area fire water spray monitors can be used to help suppress allyl alcohol vapors. 7 Surveillance: Operators routinely monitor the process. Ethylene Oxide: This scenario assumes a 1-inch drain valve on the ethylene oxide pipeline is damaged by heavy equipment during maintenance, causing a 1/32-inch wide x >-inch l ong crack to develop in a weld. The result is a release of ethylene oxide at a rate of 125 pounds per minute for 20 minutes. According to the OCA Guidance Table, this release could impact off-site public receptors. The following active mitigation measures are used in this analysis: 7 Low Pressure Alarm and Shutdown System: This shutdown system is designed to sound an alarm when a drop in pressure occurs, which is indicative of a leak and shuts the ethylene oxide distribution system down. 7 Remote Actuated Valves on Header: This valve can be remotely actuated by an operator to isolate a leak on the ethylene oxide distribution piping. This quick action can minimize the amount of material released. 7 Manual Shut-Off Valve: This valve can be closed by an operator to isolate ethylene oxide flow to plant ethylene oxide distribution system. This scenario assumes the emergency shutdown device detects and shuts down the ethylene oxide distribution system and the operator activates remote a ctuated valves on the header or closes a manual isolation valve in 20 minutes to isolate the release. In addition, specific steps to prevent this scenario from occurring, and to mitigate its effects should they occur, include: 7 Fire Water Spray Monitors: Area fire water spray monitors can be used to help suppress ethylene oxide vapors. 7 Surveillance: Operators routinely monitor the process. Vinyl Acetate Monomer: This scenario assumes a drain valve is left open on the suction side of a pump that releases vinyl acetate monomer at a rate of 387 lbs. per minute for 120 minutes. According to the OCA Guidance Table, this release could impact off-site public receptors. The following passive mitigation measure was used in this analysis: 7 Concrete Dike: The drain valve on the suction side of the pump is located in a diked area to contain and minimize evaporation of the vinyl acetate monomer. The following active mitigation measure is used in this analysis: 7 Surveillance: Operators rout inely monitor the process. This scenario assumes that the operator monitors the process area every 120 minutes and would immediately shutdown the pump. In addition, specific steps to prevent this scenario from occurring, and to mitigate its effects should they occur, include: 7 Deluge System: A water spray system designed to help suppress vinyl acetate monomer vapors. 7 Fire Water Spray Monitors: Area fire water spray monitors can be used to help suppress vinyl acetate monomer vapors. Propylene Oxide: This scenario assumes a drain valve is not closed and plugged on a propylene oxide line after maintenance, releasing propylene oxide at a rate of 1,560 lbs. per minute for 30 minutes. According to the OCA Guidance Table, this release could impact off-site public receptors. The following active mitigation measure is used in this analysis: 7 Surveillance: Operators routinely monitor the process. This scenario assumes the operator would detect the leak and take appropriate actions to i solate the leak in 30 minutes. In addition, specific steps to prevent this scenario from occurring, and to mitigate its effects should they occur, include: 7 Deluge System: A water spray system designed to help suppress propylene oxide vapors. 50% Formaldehyde: This scenario assumes a chemical transfer hose rupture during the unloading of 50% formaldehyde from a tank truck, resulting in a liquid release of 50% formaldehyde at a rate of 2,230 lbs. per minute for 20 minutes. According to the OCA Guidance Table, this release could impact off-site public receptors. The following passive mitigation measure was used in this analysis: 7 Concrete/Asphalt Berm: The berm contains and minimizes formaldehyde evaporation to the atmosphere. The following active mitigation measure is used in this analysis: 7 Operator Surveillance: An operator is required to be present while unloading 50% formaldehyde from a tank truck. This scenario assumes that the operator detects and shuts down the transfer within 20 minutes after the release. In addition, specific steps to prevent this scenario from occurring, and to mitigate its effects should they occur, include: 7 Fire Water Spray Monitors: Area fire water spray monitors can be used to help suppress formaldehyde vapors. Crotonaldehyde: This scenario assumes a chemical transfer hose rupture while unloading the vinyl methyl ether system purge from a distillation column to a tank truck, resulting in a liquid release of crotonaldehyde at a rate of 300 lbs. per minute for 15 minutes. According to the OCA Guidance Table, this release could impact off-site public receptors. The following passive mitigation measure was used in this analysis: 7 Concrete Dike: The dike drains to a process sewer and minimizes crotonaldehyde evaporation to the atmosphere. The following active mitigation measure is used in this analysis: 7 Operator Surveillance: Routine operator process monitoring and surveillance is provided. This scenario assumes that th e operator detects and shuts down the transfer within 15 minutes after the release. B) Regulated Flammable Substances Worst-Case Release Scenario(s) Vinyl Methyl Ether: The worst case release scenario for a flammable regulated substance assumes catastrophic failure of a storage tank that releases 215,000 pounds of vinyl methyl ether as a gas to the atmosphere, leading to a vapor cloud explosion. According to theOCA Guidance Table, this release could impact off-site public receptors. Specific steps to prevent this scenario from occurring, and to mitigate its effects should they occur, include: 7 Combustible Gas Detectors: The detectors are designed to detect flammable vapor and automatically actuate valves to close on storage tank, activate the deluge system, and alarm the control room. 7 Deluge System: A water spray system is designed to help suppress vinyl methyl ether vapors. It is activated by combustible gas detectors. 7 Fire Water Spray Monitors: Area fire water spray moni tors can be used to help suppress vinyl methyl ether. 7 Surveillance: Operators routinely monitor the process. Dimethylamine: The worst case release scenario for a flammable regulated substance assumes catastrophic failure of a railroad tank car that releases 163,000 lbs. of dimethylamine as a gas to the atmosphere, leading to a vapor cloud explosion. According to the OCA Guidance Table, this release could impact off-site public receptors. (A separate worst-case scenario is provided for dimethylamine because the potentially impacted public receptors associated with dimethylamine releases are different from those associated with vinyl methyl ether releases.) Specific steps to prevent this scenario from occurring, and to mitigate its effects should they occur, include: 7 Combustible Gas Detectors Interlocked to Deluge System: This system is designed to detect flammable vapors and to automatically activate the deluge system (water spray) to suppress dimethylamine vapors. 7 Safety Reli ef Device: This device is designed to relieve pressure at a predetermined set point and prevent over pressure of the railroad tank car. 7 Fire Water Spray Monitors: Area fire water spray monitors can be used to help suppress dimethylamine vapors. 7 Surveillance: Operators routinely monitor the process. Alternative Release Scenario Methylamine: The alternative-case release scenario for a flammable regulated substance assumes a safety relief valve fails and prematurely opens on a tank car, releasing methylamine at a rate of 9,940 lbs. per minute for 16.4 minutes as a gas to the atmosphere (entire tank contents), leading to a vapor cloud explosion. According to the OCA Guidance Table, this release could impact off-site public receptors. Specific steps to prevent this scenario from occurring, and to mitigate its effects should they occur, include: 7 Surveillance: Operators routinely monitor the process. 7 Combustible Gas Detectors Interlocked to Deluge System: This system is designed to detect flammable vapor and to automatically activate the deluge system (water spray) to help suppress methylamine vapor. 7 Fire Water Spray Monitors: Area fire water spray monitors can be used to help suppress methylamine vapors. 4 General Accidential Release Prevention Program General Program Our general accident prevention program consists of compliance with the EPA RMP rule and OSHAs PSM standard and implementation of Union Carbides Operational Safety Program and Episodic Risk Management System. Key elements include: Equipment Design: Vessels (including shipping containers) and other process equipment are designed according to recognized industry standards and/or governmental requirements. Process Safety Information: Chemical hazard, process technology, and equipment information is documented, maintained up-to-date, and available to operating personnel. Process Hazard Analysis: Process hazard analyses are conducted every five years to identify major process hazard scen arios and to recommend corrective action(s) needed to prevent their occurrence. Episodic Risk management System: Periodic reviews are conducted to identify hazards which could have significant community impact and to recommend corrective action(s) needed to prevent their occurrence. These reviews utilize advanced quantitative risk assessment techniques. Operational Safety Standards: Design requirements for active and passive mitigation controls used to prevent major process hazards are documented in operational safety standards. Operating Procedures: Operating procedures provide detail on how to safely operate a process and are maintained up-to-date. Operator Training/Certification Program: The plant has a training and testing program which provides operators with the proper skills and knowledge prior to allowing them to independently operate a process. Technical Staff Training and Support: Trained technical staff employees are available 24 hours a day to support operations. Main tenance Procedures: The plant has specific procedures for maintaining process equipment so that it operates safely. Maintenance Training: The plant trains persons who perform routine or complex maintenance tasks on process equipment. Mechanical Integrity Program: Vessels (including shipping containers) and other process equipment are periodically tested and inspected to ensure safe operation of process equipment, following recognized standards and/or government requirements. Management of Change: The plant has a management system to ensure that modified facilities and processes are safe for operation. Pre-Startup Safety Reviews: Reviews are conducted just prior to startup to ensure that modified facilities and processes are safe for operation. Incident Investigation: The plant has a program to ensure accidents and incidents are properly investigated to determine the cause(s) and implement corrective action(s) that are needed to prevent the event from reoccurring. Employee Particip ation: The plant has a program to involve employees in prevention program elements. Hot Work Permit: The plant has a procedure to ensure that welding, cutting and brazing are safely performed in areas where flammable or combustible material may be present. Contractor Safety Program: The plant has a program to ensure that contractors are properly trained and perform their work in compliance with safety requirements. Compliance Audits: Periodic Corporate and plant-led audits are conducted to ensure that process operations comply with governmental and Union Carbide requirements. Operational Safety Program: Union Carbide has a comprehensive program to ensure that all the elements listed above are implemented at every Union Carbide location. This program includes accountabilities for timely and proper implementation of the program elements. These general prevention elements and the chemical specific steps discussed in the previous section are parts of an overall management system to prevent accidental chemical releases. Our company and our employees are committed to the standards that these management systems set. We have specific accountabilities and controls to ensure that we are meeting our own high standards for accident prevention. 5 Five-Year Accident History In the last five years there has not been an accident or incident involving an EPA RMP chemical at the Union Carbide South Charleston Plant that resulted in an on-site death, injury, or property damage; or a known off-site death, injury, evacuation, shelter-in-place, property damage or environmental damage. 6 Emergency Response Program The South Charleston Plant maintains a written emergency response program to protect worker and public safety, as well as the environment. The program consists of procedures for responding to releases of hazardous substances, including the possibility of a fire or explosion if a flammable substance is accidentally released. The procedures address all aspects of emer gency response including: 7 Proper first-aid and medical treatment for exposures 7 Evacuation plans and accounting for personnel after an evacuation 7 Notification of local emergency response agencies and the public if a release occurs 7 Post-incident cleanup and decontamination requirements, and 7 Inspecting, testing, maintaining, and using emergency response equipment. The emergency response program is updated when necessary based on modifications made to facility processes. The South Charleston Plant maintains a trained emergency squad to handle fires, explosions, toxic vapor releases, spills, and medical emergencies. The plant emergency squad trains and drills with local emergency responders to enhance their skills and tactics for responding to an accidental chemical release. Critiques are held on drills and actual events. In addition to the plant emergency squad, Union Carbide staffs a Hazardous Emergency Leaks Prevention (HELP ) team in the Kanawha Valley that responds to accidental releases from transportation equipment throughout the continental United States. The emergency response program provides the essential planning and training for effectively protecting workers, the public, and the environment during emergency situations. Detailed emergency response plans are developed and coordinated with the Kanawha/Putnam emergency Planning Committee and the community. 7 Planned Changes to Improve Safety The following is a list of improvements that we are planning to implement at the facility to help prevent and/or better respond to accidental chemical releases: 7 Implement a new Corporate program which utilizes semi-quantitative assessment techniques in process hazard analyses to ensure that controls used for prevention or mitigation of hazards provide adequate protection 7 Implement a new Corporate program designed to ensure that process safety information is maintained evergreen 7 Implement the Apollo Root Cause Analysis problem solving technique to identify causes of process problems and effective solutions to prevent their reoccurrence 7 Repaint the allyl alcohol storage tank to protect against weathering and rust 7 Add redundant relays and switches to some existing unit instrumentation 7 Upgrade control systems for better reliability and capability 7 Install CGA Lower Explosive Limit analyzers in an operating unit for continuous monitoring of flammable vapors 7 Repaint Ethylene Oxide Distribution System piping to protect against weathering and rust 7 Perform thickness measurements on the Ethylene Oxide Distribution piping 7 Perform strength test and take thickness measurements on a unit propylene oxide header 7 Install redundant instrumentation in a unit 7 Implement a Corporate-wide strategy to avoid computer hardware and software systems operating disruptions due to the year 2000 changeover. The latest information on the company's Y2K efforts can be found on our Internet site -- www.unioncarbide.com. this information will b e periodically updated through first quarter 2000. |