Dow Chemical Torrance California Site - Executive Summary |
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General Executive Summary For The Dow Chemical Torrance California Facility June 1999 Accidental Release Prevention and Emergency Response Policies The Dow Chemical Company ("Dow") has a long-standing commitment to worker and public safety. This commitment is demonstrated by the resources invested in accident prevention, such as training personnel and considering safety in the design, installation, operation, and maintenance of our processes. Our policy is to implement reasonable controls to prevent foreseeable releases of regulated substances. However, if a release does occur, our trained personnel will respond to isolate and deny entry and control the release to the extent possible. Dow personnel will also notify the Torrance Fire Department who will assume command of the incident, if necessary, until the release is stopped. Description of the Stationary Source and Regulated Substances The Dow facility, located in Torrance, CA, primary activities are the manufacturing of p olystyrene plastic and Styrofoam(r) extruded polystyrene board. Ethyl chloride is the only regulated substance present at our facility, and is used to manufacture Styrofoam(r) insulation building materials. Worst Case Scenario Alternative Release Scenario with Administrative Controls and Mitigation Measures The ethyl chloride storage tank and tank car unloading process is subject to the requirements of the EPA's RMP regulation. This regulation requires Dow to analyze the process to determine the worst case release scenario and an alternative, or more likely, release scenario. The worst case release scenario submitted for this process involves a catastrophic release of 274,000 lb. of ethyl chloride from the storage tank. The storage tank's dike was considered as a passive mitigation system when evaluating this scenario. Passive mitigation systems are those devices, equipment, or technologies that function without human, mechanical, or other energy source. It is assumed that the entire quantity is released as a vapor, which finds an ignition source, with 10 percent of the released quantity participating in a vapor cloud explosion. An overpressure of 1 psi, resulting from the explosion would be experienced beyond our fence line. The effects of a 1 psi overpressure include broken windows and possible significant damage to buildings, depending of the type of structure. The alternative release scenario submitted involves a release of 49,800 lb. of ethyl chloride, in 10 minutes, resulting from the rupture of a 2" ethyl chloride tank car unloading hose. The release is assumed to result in a Vapor Cloud Explosion. The tank car's spill containment was considered as a passive mitigation system when evaluating this scenario. Based on the alternative release scenario, an overpressure of 1 psi, resulting from the explosion would be experienced beyond our fence line. The active mitigation measure for the ethyl chloride tank car is the deluge fire protection sys tem. Active mitigation systems are the converse of passive mitigation systems, in that they require human, mechanical, or other energy sources to function. The release is also controlled by monitoring and detection systems including 1) flammable gas detectors, 2) a television camera, 3) sensors measuring pressure, temperature, and level deviations. The EPA RMP*Comp(TM) methodology, developed by the Environmental Protection Agency (EPA), was used to model both the worst case and alternative release scenarios. General Accidental Release Prevention Program Steps Our facility has taken all the necessary steps to comply with the accidental release prevention requirements set out under 40 CFR part 68 of the EPA. All facilities at the Dow Torrance, CA site were designed and constructed in accordance with the Uniform Building Code, Uniform Fire Code, and all other applicable codes and standards in place at the time of construction. A number of processes at our facility are subject to th e OSHA PSM standard under 29 CFR 1910.119. Our facility is also subject to EPCRA Section 302 notification requirements. We also have an air operating permit ID under Title V of the Clean Air Act. The following sections briefly describe the elements of the release prevention program that is in place at our stationary source. Employee Participation Dow truly believes that process safety management and accident prevention is a team effort. Company employees are strongly encouraged to express their views concerning accident prevention issues and to recommend improvements. Specific examples of employee participation range from writing and updating operating procedures to participating as a member of: 1) accident investigation teams, 2) project pre-startup reviews, and 3) process hazard analysis (PHA) teams. All employees are encouraged to report any unsafe conditions and to initiate the Management of Change process to correct the condition. Dow employees are also encouraged to inte rvene in unsafe acts to prevent injury to other employees. Employees have access to all information created as part of the Torrance site Injury and Illness Prevention Program. In addition, the Torrance site has a Site Safety Steering Committee whose function is to address overall site process safety and employee safety issues. The Site Safety Steering Committee has members from various areas of the plant, including operations, maintenance, engineering and plant management. Process Safety Information Dow keeps a variety of technical documents that are used to help maintain safe operation of the processes located at the Torrance, Ca site. These documents address chemical properties and associated hazards, limits for key process parameters and specific chemical inventories, and equipment design basis/configuration information. Chemical-specific information, including exposure hazards and emergency response/ exposure treatment considerations, is provided in material safety data shee ts (MSDSs). This information is supplemented by documents that specifically address known corrosion concerns and any known hazards associated with the inadvertent mixing of chemicals. Safety-related limits for specific process parameters (e.g., temperature, level, and composition) are maintained in documentation located in the Styrofoam (r) plant control room. Dow ensures that the process is maintained within these limits using process controls and monitoring instruments, highly trained personnel, and protective instrument systems (e.g., automated shutdown systems). These reference documents are readily available to all employees. Several of these documents are also supplied to the Torrance Fire department, such as MSDSs and site maps, which show location of hazardous materials storage. Specific departments within the facility are assigned responsibility for maintaining up-to-date process safety information. Dow also maintains numerous technical documents that provide informatio n about the design and construction of process equipment. This information includes materials of construction, design pressure and temperature ratings, electrical rating of equipment, etc. This information, in combination with written procedures and trained personnel, provides a basis for establishing inspection and maintenance activities, as well as for evaluating proposed process and facility changes to ensure that safety features in the process are not compromised. Process Hazard Analysis (PHA) Dow has a comprehensive program to help ensure that hazards associated with the various processes are identified and controlled. Within this program, each process is systematically examined to identify hazards and ensure that adequate controls are in place to manage these hazards. Dow primarily uses the Fire and Explosion Index (F&EI) and Chemical Exposure Index (CEI) analysis techniques as screening methods to determine the need for more rigorous PHA methodologies. OSHA recognizes F& EI and CEI as effective PHA methodologies. If the F&EI and/or CEI analyses determine that a significant hazard exists from a process unit, then a Hazard and Operability (HAZOP) study is completed for the unit. In all cases, the analyses are conducted using a team of people who have operating and maintenance experience as well as engineering expertise. This team identifies and evaluates hazards of the process, and makes recommendations for additional prevention and/or mitigation measures as needed. A relative risk ranking is assigned to the recommendations to aid in prioritization of the corrective actions. The PHA team recommendations are then forwarded to local management for review. Local management prioritizes the recommendations, compiles a corrective action list with responsible parties and target completion dates and forwards this to corporate management for final review. Local management is accountable for the completion and documentation of these items. To help ensure t hat the process controls and/or process hazards do not deviate significantly from the original design safety features, the Dow facility periodically updates and revalidates the hazard analysis results. These periodic reviews are conducted at least every 5 years and will be conducted at this frequency until the process is no longer operating. The results and findings from these updates are documented and retained. Once again, the team findings are forwarded to local management to be prioritized and addressed accordingly. Operating Procedures Dow maintains operating procedures written to provide clear instructions for safely conducting activities associated with the process. The operating procedures include the following items. * Startup * Normal Operations * Shut down * Emergency Shutdown * Startup following a turnaround or emergency shutdown These procedures can be used as a reference by experienced operators and provide a basis for consistent training of new operators. The o perating procedures are maintained current and accurate by revising them as necessary to reflect changes made through the management of change process. In addition, the Dow Styrofoam(r) manufacturing facility maintains information describing normal operations in a set of documents called "Best Run Data". Operating limits, consequences of deviation from these limits, and recommended actions that should be taken to avoid or correct the deviation are found in the process control computer logic programming documentation. This information, along with written operating procedures, is readily available to operators and for other personnel to use as necessary to safely perform their job tasks. Training To complement the written procedures for process operations, the Dow Styrofoam(r) manufacturing facility has implemented a comprehensive training program for all employees involved in operating a process. New employees receive basic training in personal safety, plant operations overview, a nd emergency response via the "Minimum Requirements Checklist". After successfully completing this training, a new operator is paired with a senior operator to learn process-specific duties and tasks. After operating technicians demonstrate (e.g., through oral tests and skills demonstration) the knowledge adequate to perform the duties and tasks in a safe manner on their own, they can work independently. The entire initial training process takes approximately two years to complete. In this two-year period, operating technicians only perform those tasks that they have demonstrated competency in. Additionally, all operating technicians periodically receive refresher training on plant systems to ensure that their skills and knowledge are maintained at an acceptable level. This refresher training is conducted at least every 3 years. All of this training is documented for each operator, including the means used to verify that the operator understands the training. Contractors Dow us es contractors to supplement its work force during periods of increased maintenance or construction activities, and to supplement the manufacturing work force. Because contractors can work with, on, or near process equipment, the plant has procedures in place to ensure that contractors: 1) perform their work in a safe manner, 2) have the appropriate knowledge and skills, 3) are aware of the hazards in their workplace, 4) understand what they should do in the event of an emergency, 5) understand and follow site safety rules, and 6) inform Dow personnel of any hazards that they find during their work. This is accomplished by providing contractors with: 1) a process overview, (2) information about safety and health hazards, 3) emergency response plan requirements, and 4) safe work practices prior to their beginning work. A Dow plant representative verifies that these items have been accomplished through the safe work permit process. In addition, Dow evaluates contractor safety program s and performance during the selection of a contractor. Dow personnel periodically monitor contractor performance to ensure that contractors are fulfilling their safety obligations. Pre-startup Audits Dow conducts a Pre-startup audit for any new facility or facility modification that requires a change in the process safety information. The purpose of the Pre-startup audit is to ensure that: safety features, procedures, personnel, and the equipment are appropriately prepared for startup prior to placing the equipment into service. This audit provides one additional check to make sure construction is in accordance with the design specifications and that all supporting systems are operationally ready. The Pre-startup audit team uses checklists to verify all aspects of readiness. A Pre-startup audit involves field verification of the construction and serves a quality assurance function by requiring verification that requirements of all Dow "Safety Standards" and "Loss Prevention Pr inciples" are properly implemented. Mechanical Integrity Dow has well-established practices and procedures to maintain pressure vessels, piping systems, relief and vent systems, controls, pumps and compressors, and emergency shutdown systems in a safe operating condition. The basic aspects of this program include: 1) conducting training, 2) developing written procedures, 3) performing inspections and tests, 4) correcting identified deficiencies, and 5) applying quality assurance measures. In combination, these activities form a system that maintains the mechanical integrity of the process equipment. Dow employs contract service companies that perform required pressure vessel and process piping integrity thickness testing and inspections, who use procedures developed by the American Petroleum Institute (API), and the American Society of Mechanical Engineers (ASME). These companies are required to demonstrate accepted industry qualifications and training, in order to perform these tests and inspections. Dow personnel perform vibration analysis, oil analysis and lubricate pumps and compressors per written procedures, to help ensure that equipment functions as intended, and to verify that equipment is operating within acceptable limits. If a deficiency is identified, employees will correct the deficiency before placing the equipment back into service (if possible), or an MOC team will review the use of the equipment and determine what actions are necessary to ensure the safe operation of the equipment. The qualifications to perform these tests include training on: 1) an overview of the process, 2) safety and health hazards, 3) applicable maintenance procedures, 4) emergency response plans, and 5) applicable safe work practices to help ensure that they can perform their job in a safe manner. Another integral part of the mechanical integrity program is quality assurance. Dow incorporates quality assurance measures into equipment purchases and repairs. This helps ensure that new equipment is suitable for its intended use and that proper materials and spare parts are used when repairs are made. Safe Work Practices Dow has long-standing safe work practices in place to help ensure worker and process safety. Examples of these include 1) control of the entry/presence/exit of support personnel, 2) a lockout - tagout procedure to ensure isolation of energy sources for equipment undergoing maintenance, 3) a procedure for safe removal of hazardous materials before process piping or equipment is opened, 4) a permit and procedure to control spark-producing activities (i.e., hot work), and 5) a permit and procedure to ensure that adequate precautions are in place before entry into a confined space. Dow also maintains a strictly enforced no-drug policy. These procedures (and others), along with training of affected personnel, form a system to help ensure that operations and maintenance activities are performed safely. Management of Change Dow ha s a comprehensive system to manage changes to processes. This system requires that changes to items such as process equipment, chemicals, technology (including process operating conditions), procedures, and other facility changes be properly reviewed and authorized before being implemented. Changes are reviewed to: 1) ensure that adequate controls are in place to manage any new hazards and 2) verify that existing controls have not been compromised by the change. Affected process safety information, process operating limits, and equipment information, as well as procedures, are updated to incorporate these changes. In addition, operating and maintenance personnel are provided any necessary training on the change. Incident Investigation Dow promptly investigates all incidents that resulted in, or reasonably could have resulted in, a fire/explosion, toxic gas release, major property damage, environmental loss, or personal injury. The goal of each investigation is to determine the fa cts and develop corrective actions to prevent a recurrence of the incident or a similar incident. The investigation team documents its findings, develops recommendations to prevent a recurrence, and forwards these results to plant management for resolution. Corrective actions taken in response to the investigation team's findings and recommendations are tracked until they are complete. The final resolution of each finding or recommendation is documented, and the investigation results are reviewed with all employees (including contractors) who could be affected by the findings. Incident investigation reports are retained for at least 5 years so that the reports can be renewed during future PHAs and PHA revalidations. Compliance Audits To help ensure that the accident prevention program is functioning properly, Dow periodically conducts an audit of our procedures and practices for both accuracy and compliance. Audits are conducted at least every 3 years with both hourly and manage ment personnel as audit team members. The audit team develops recommendations that are forwarded to local management for review. A prioritized corrective action list with responsible parties and target completion dates is generated to address each of the audit team's recommendations. Local management is accountable for the completion and documentation of these items. The two most recent audit reports including corrective actions are retained at all times. Compliance audits are conducted for the areas of: 1) Reactive Chemicals, 2) Process Safety, 3) Personal Safety, 4) Industrial Hygiene, 5) Hazardous Materials Transportation, and 6) Security. Chemical Specific Prevention Steps The Dow ethyl chloride storage tank and tank car unloading process must be managed to ensure continued safe operation. The prevention programs summarized previously help prevent potential accident scenarios that could be caused by equipment failures and human errors. In addition to the prevention pro gram activities, the ethyl chloride storage tank and tank car unloading process have safety features to help: 1) quickly detect a release, 2) contain/control a release, and 3) reduce the consequences of (mitigate) a release. The following types of safety features are used in various processes: Release Detection * Flammable gas detectors with alarms * Television camera which is monitored in the plant control room * Sensors measuring pressure, temperature, and level deviations Release Containment / Control * Valves to permit isolation of the process (manual or automated) * Automated shutdown systems for specific process parameters (e.g., high level, high pressure) * Diking to contain liquid releases * Redundant equipment and instrumentation (e.g., uninterruptible power supply for process control system, backup firewater pump) * Pressure relief devices Release Mitigation * Fire suppression deluge systems * Emergency response trained to First Responder Operations level and I ncident Commander * Personal protective equipment (e.g., protective clothing, self-contained breathing apparatus) Five-Year Accident History The Dow Styrofoam(r) production facility has handled ethyl chloride for 15 years. Due to our effective safety management systems, there have been no releases of ethyl chloride which have resulted in a fire, injury, or adverse impact to the environment on or off site during this 15 year period. Emergency Response Program Information The Dow facility maintains a written emergency response plan, which is in place to protect worker and public safety as well as the environment. The plan consists of procedures for responding to a release of hazardous materials including ethyl chloride. Included in these procedures is the possibility of a fire or explosion if a flammable substance is accidentally released. The procedures address evacuation plans and accounting for personnel after an evacuation, notification of local emergency response agencies, and post incident cleanup and decontamination requirements. In addition, Dow has procedures that address maintenance, inspection, and testing of emergency response equipment. Employees receive training in these procedures as necessary to perform their specific emergency response duties. The emergency response plan is updated when necessary based on modifications made to plant processes or other. The emergency response program changes are administered through the MOC process, which includes informing and/or training affected personnel in the changes. The overall emergency response program for the Dow facility is coordinated with the Torrance Fire Department. This coordination includes periodic tours, training and Hazardous Material incident drills. Dow can notify the Torrance Fire Department 24 hours/day via 911. This provides a means of notifying the public of an incident, if necessary, as well as facilitating quick response to an incident. The Dow facility also conducts dril ls periodically with the Torrance Fire Department to facilitate training of their personnel. Planned Changes to Improve Safety The Dow facility resolves all findings from PHAs, some of which result in modifications to the process. The following types of changes are planned: * Reduction of ethyl chloride usage * Address Seismic Assessment recommendations to upgrade ethyl chloride storage tank and piping systems, and fire protection systems as determined to be necessary * Review and update of Piping and Instrument Diagrams * Review and update of pressure relief valve and pressure vessel calculations * Revisions to personnel training program * Revisions to operating procedure program |