Dow Chemical Company Torrance California Site - Executive Summary |
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Dow Chemical Torrance, CA Site General Executive Summary January, 2001 Section 1. 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. Section 2. Description of the Stationary Source and Regulated Substances The Dow facility, located in Torrance, CA, primary activities are the ma nufacturing of polystyrene plastic and polystyrene foam products. Acrylonitrile is the only regulated substance present at our facility, and is used to manufacture ABS (Acrylonitrile-Butadiene Rubber-Styrene Polymer) plastic. ABS resins have unique chemical resistance, toughness, and high temperature properties that make them especially suitable for a number of end uses including automotive parts; drain, waste, and vent pipes; small appliances; electronic equipment housings; housewares; toys; and many more. The Torrance Plant is one of many locations in North America and Europe in which Dow produces ABS plastic resin. Dow has been producing ABS resins since the early 1960s and remains today one of the largest producers worldwide. Production of ABS in Torrance started in 1972 to meet West Coast demand as well as export pportunities. ABS continues to be a vital component of the portfolio of products offered by Dow to its global customers Section 3. Worst Case Scenario Alternative Release Scenario with Administrative Controls and Mitigation Measures The EPA's RMP regulation covers the acrylonitrile storage tank and tank car unloading process and the ABS production process equipment. This regulation requires Dow to analyze these processes to determine the worst case release scenario and an alternative, or more likely, release scenario. The worst case release scenario submitted for these processes involves a catastrophic release of 274,000 lb. of acrylonitrile from an acrylonitrile storage tank. The tank's containment 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 instantaneously, to form a liquid pool. The amount of acrylonitrile that vaporizes in this worst case scenario forms a mixture in air, which a person can be exposed to for an hour, without experiencing serious health effects. This mixture would be experienced beyond the Dow Chemical facility fence line The alternative release scenario involves the acrylonitrile storage tanks, just as in the worst case scenario. In the alternative release scenario, it is assumed that a 2 inch opening develops on one of the storage tanks, resulting from the failure of a 2" piping connection to the tank, or a partial failure of the tank itself. The liquid acrylonitrile would be released at rate of 1262 pounds per minute into the tank dike forming a contained liquid pool. It is assumed that the release would last for 10 minutes, for a total liquid release amount of 12,620 lbs. This is a reasonable time frame for operations personnel to become aware of the problem and take appropriate actions to stop the release. It is assumed that the release would be detected by the flammable gas detector located in the dike, which would sound in an alarm audible both inside and outside the control room. The storage tank spill containment was considered as a passive mitigation system when evaluating this scenario. The active mitigation measure for the acrylonitrile storage tank system is the deluge fire protection system with fire fighting foam capability. Fire fighting foam, applied to the surface of a liquid pool, reduces the liquid evaporation rate. 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, and 2) sensors measuring pressure, temperature, and level. Based on the alternative release scenario, the concentration of acrylonitrile in air would be experienced beyond the Dow Chemical facility fence line, which a person can be exposed to for an hour, without experiencing serious health effects. The EPA RMP*Comp(TM) met hodology, developed by the Environmental Protection Agency (EPA), was used to model both the worst case and alternative release scenarios. Section 4. 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 the 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. a) 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 intervene 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 S afety Steering Committee has members from various areas of the plant, including operations, maintenance, engineering and plant management. b) 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 sheets (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 t he 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 information 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. c) 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. A HAZOP was completed for the acrylonitrile unloading and storage area, and the ABS plastic production uni t, in January of 1996, to fulfill the PHA requirement for the California Risk Management and Prevention Program (a program eventually replaced by the RMP). This HAZOP is considered to also fulfill the requirements for the Risk Management Plan, since no significant modifications were made to these processes. In all cases, the analyses are conducted using a team of people who have operating an 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 that 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. d) 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 procedu res can be used as a reference by experienced operators and provide a basis for consistent training of new operators. The operating procedures are maintained current and accurate by revising them as necessary to reflect changes made through the management of change process. In addition, Dow maintains information describing normal operations. 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. e) Training To complement the written procedures for process operations, Dow has implemented a comprehensive training program for all employees involved in operating a process. New employees receive basic training in personal safety, plant operation s overview, and emergency response via the "Minimum Requirements Checklist." After successfully completing this training, a new operator is assigned to a training shift, with a senior training special 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. During the initial training process, 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. f) Contractors Dow uses contr actors 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 giving each contractor a safety orientation, when they come on site, which includes information about: 1) safety and health hazards, 2) emergency response plan requirements, and 3) 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, which also includes a revi ew of job specific hazards. In addition, Dow evaluates contractor safety programs and performance during the selection of a contractor. Dow personnel periodically monitor contractor performance to ensure that contractors are fulfilling their safety obligations. g) 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 Principles" are properly implemented. h) 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). The se 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 in tegrity 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. i) 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 o f affected personnel, form a system to help ensure that operations and maintenance activities are performed safely. j) Management of Change Dow has 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. k) Incident Investigation Dow promptly investigates all incidents that resulted in, or reasonably could h ave 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 facts 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. l) Compliance Audits To help ensure that the accident prevention program is functio ning 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 management 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. Section 5. Chemical Specific Prevention Steps The Dow Acrylonitrile storage tank, tank car unloading, and ABS production processes must b e 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 program activities, these processes 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 ? 100% attendance during entire tank car unloading process ? 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 ? Fire fighting foam to minimize evaporation ? 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 with fire fighting foam capability ? Emergency response trained to First Responder Operations level and Incident Commander ? Personal protective equipment (e.g., protective clothing, self-contained breathing apparatus) The Dow Acrylonitrile 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. Section 6. Five-Year Accident History There have been no releases of acrylonitrile which have resulted in a fire, injury, or adverse impact to the environment, or had any off site impact during the last 5 years. Section 7. Emergency Response Program Information The Dow facility maintains a written emergency response pl an, 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 acrylonitrile. 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 affec ted 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 drills periodically with the Torrance Fire Department to facilitate training of their personnel. Section 8. Planned Changes to Improve Safety ? The Dow facility plans to complete a revalidation of Hazard and Operability (HAZOP) study, and correcting any noted deficiencies. ? Evaluate building a acrylonitrile tank car containment dike within the Styrene storage tank containment to reduce Toxic Endpoint distance, in the event of a release. ? Addition of foam fire suppression capability to the existing ABS plastic production structure deluge system. ? Evaluate feasibility of adding an automatic emergency block valve on the acrylonitrile tank car unloading hose. The expected completion date for these changes is January, 2002 |