The Gas Company SNG Plant - Executive Summary |
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Accidental Release Prevention and Emergency Response Policies The Gas Company owns and operates a synthetic natural gas plant as part of its gas distribution system on the Island of Oahu. The Facility operates under strict federal and state regulations for safety of its employees, its products and the environment. By maintaining a comprehensive safety program and documenting the program in this Risk Management Plan, The Gas Company is complying with HIOSH and OSHA Process Safety Management Standards (called PSM) and EPA's Risk Management Program regulations (called RMP). The Gas Plant has been safely operating since 1974. At The Gas Company, we realize that constant diligence in operation and proper maintenance of our facility can reduce risks to our workers and to the public. This RMP documents the procedures and controls in place to ensure that accidental releases of flammable materials are prevented and to promptly respond to and mitigate any incident that does occur. Our RMP and PSM programs are applied to all onsite activities that could involve or affect the facility. Our safety programs prevent accidents because they focus on the rules, procedures and practices that govern individual processes, activities or pieces of equipment. These rules are periodically reviewed and improved as necessary. They are also communicated to and accepted by all employees at the facility. Stationary Source and Regulated Substances A mixture of flammable liquids and gases called naphtha is transfered by pipeline from an adjacent refinery and stored in pressure vessels. The mixture is largely butane gas and other light hydrocarbons. A total storage capacity of 600,000 lb. is stored in 5 pressure vessels. The naphtha is then pumped into the process facility, which uses a series of catalytic reactions to manufacture synthetic natural gas (called SNG). The processes utilize catalysts in fixed beds and in tubes. Catalysts are solid materials that promote the reaction of naphtha and its components with hydrogen and oxygen to form SNG and a byproduct, CO2 is then supplied to a product pipeline. The CO2 is piped to a local plant that bottles the gas and makes dry ice. The SNG is distributed throughout the City of Honolulu and a number of surrounding communities. System components include boilers, compressors, condensers, reactors, accumulators, piping and valves, instrumentation and controls and other miscellaneous components. Naphtha and its components are highly flammable and stored as a pressurized liquid 5 horizontal storage tanks. The tanks are protected by a water deluge system as well as fixed hydrants and monitors. The process plant is located a considerable distance away from the storage area and it is unlikely that a fire in the process would involve the storage vessels. The vessels are connected to the process by piping and therefore the process facility has been included in the RMP. The primary hazard of the stored products and the process facility is the risk of explosion or fire. The butane and other feed components are not considered acutely toxic material, although it could cause asphyxiation in large quantities. General Accident Release Prevention Program The SNG Plant has integrated program elements described in the RMP to deal with the risks involved with the storage and handling of naphtha and other flammable materials throughout the manufacturing process. In this way, we promote overall plant, worker and public safety. These program elements include: Process Safety Information - The facility has been designed and installed by reputable vendors who are well known in the industry. We require that information on the design and operation of the facility be documented and maintained for as long as we operate it. Process Hazard Analysis - Our processes involving flammables have been thoroughly analyzed for unseen hazards using techniques that are common in process industries. Using trained teams of e mployees, with experienced hazard analysis leaders, we systematically review the details of design and construction. Hazard analyses generate items that potentially could pose a risk to operations, could reduce risk or could improve operability. The hazard analysis findings are analyzed to determine if a change to the facility would be beneficial. Items are addressed on a priority basis based upon safety and feasibility. Operating Procedures - Formal written procedures for operation and maintenance of our facility have been developed. Procedures provide steps for each operating phase, they also document operating limits, safety and health considerations, and safety systems and their functions. Training - The Gas Company has a very experienced workforce. The average experience of operators is 7 years. The Gas Company certifies that their operators are competent. In the past, we have ensured that newly hired employees are proficient at safely carrying out their duties and respon sibilities before assigning them to critical tasks. Mechanical Integrity - Preventive maintenance practices have been in place since the facility was constructed in 1974. We perform routine safety checks, inspections and preventive maintenance tasks to reduce the likelihood and severity of equipment failures. Outside experts, including pressure vessel and piping inspectors are employed as needed to provide ongoing verification of the integrity of the system. Hot work procedures, Lockout/Tagout procedures and others are used to document and control safe work practices. Management of Change - Changes to the process, including chemicals, technology, equipment and procedures and changes to equipment that could affect the process or storage of flammables are managed through use of a written management of change procedure. Designated management personnel must authorize changes under this program element. Pre-startup Safety Review - Before a major change can be instituted, Pre-startup Safety Review requires that Construction and equipment is in accordance with design specifications, procedures are in place and adequate, process hazard analysis is performed and recommendations resolved and training is conducted. Compliance audits - Under the RMP, The Gas Company is required to evaluate compliance with the RMP and PSM regulations at least every three years. Incident Investigation - The RMP requires that incidents which resulted in or could reasonably resulted in a catastrophic release of naphtha be investigated promptly by a team of investigators with the appropriate knowledge and experience to thoroughly investigate and analyze the incident. Employee Participation - We actively encourage and require our employees to participate in program development and enforcement. We have a documented system that verifies employee participation in each program element. Hot Work Permit - Before work is performed which involves a potential source of ignition, designated person nel must inspect the work area, review the procedures and document the precautions necessary to prevent fires or explosions. The written permit authorizes work on specific dates and on specific equipment. Contractors - The Gas Company has a program in place to collect safety program and performance information from its contractors and evaluate the contractors suitability. Contractors are audited to verify that they are meeting their obligations under the RMP and other facility safety rules. The contractor's safety record, training program and procedures are evaluated before they are hired and periodically during the course of the contract. Five year Accident History EPA requires that facilities document a five year history of accidental releases that caused a serious onsite or offsite consequences. The SNG Plant has had no reportable accidents in the last five years. Release Scenarios EPA requires that facilities document a theoretical worst case and alternative release scena rios to prompt public participation and discussion in chemical safety and emergency preparedness. The following scenarios have been developed following EPA's specific modeling assumptions and requirements. The assumptions require pessimistic assumptions of wind speed, air stability and other factors that are not typical conditions for the area. Worst Case Release Scenario Following EPA's requirements for modeling releases, under worst case conditions, failure of the largest storage vessel containing naphtha would result in a vapor cloud that could find a source of ignition and explode. Such a release could result in an overpressure of one pound per square inch (1 PSI) up to 0.4 miles from the facility. 1 PSI is the threshold set by EPA as the value that could be hazardous to people. No residences or other sensitive populations or environments are present in the area described by the scenario. There are however, commercial, industrial and military properties in the area. This scenario is unlikely for the following reasons: -The storage area is provided with a deluge fire protection system and fixed monitors to help control fires and explosions. -Flammables are typically contained in piping and vessels throughout the system that could be isolated before a large amount of flammable material is released. -Worst- case weather conditions are uncommon. -Industry standards for the manufacture and quality control of pressure vessels and piping are employed by the facility. -Naphtha is not particularly corrosive in this service; pressure safety valves limit operating pressure in this vessel; program in place at the facility includes regular maintenance, inspection, testing, and replacement of equipment. The facility is also protected by a flare system that is designed to safely burn off gas discharges before it can accumulate in explosive quantities. -The facility is continuously supervised by competent individuals who are trained to identify poten tial problems and to isolate leaks if they occur. Alternative Release Scenario EPA also requires identification of an alternative release scenario. The alternative release scenario for our facility is a small pipe failure or line leak of 1-inch hole size, resulting in a release of naphtha at 1,500 LB/min for 30 minutes. The flammable cloud could travel up to 160 feet in typical weather conditions before dispersing below the flammable concentration. In this hypothetical scenario the operator would detect and isolate the release in 30 minutes. Flammable detectors are located in the process area of the facility and water monitors are available to assist in dispersing a flammable vapor cloud. The Gas Company SNG Facility has in place each element of the prevention program to reduce the likelihood and consequences of this scenario. Mechanical integrity, prestart-up safety review, management of change and operating procedures help prevent this type of incident. By procedure, all d rains are verified closed and secured at time of startup. Emergency Response Program The SNG facility has an emergency response plan to address actions taken by employees during an emergency. The plan provides for immediate response by facility operators and for emergency notification of public and company response resources. The emergency response plan details how The Gas Company will interface with the public and local agencies. All employees at the facility are periodically trained in the provisions of the emergency plan and the relevant aspects of the Incident Command System utilized by The Gas Company and other response agencies. The Gas Company is also an active participant in Campbell Local Emergency Action Network, a volunteer organization established to promote emergency planning and public education in the Campbell Industrial Park. As a member of CLEAN, the Gas Company recently participated in an initiative to develop the award winning Campbell Industrial Park Emergen cy Management Plan. It provides comprehensive information to the nearby communities and to Park businesses on emergency preparedness. It has established a framework for emergency coordination among both private and public response groups. The Fire Department and Honolulu City and County Civil Defense actively participate in CLEAN activities and assisted in developing the plan. CLEAN recently launched an initiative to purchase and distribute emergency alert radios throughout the Industrial Park and nearby sensitive populations that could be affected by an emergency. These devices, when activated through the Emergency Alert System can provide warning and instruction to Campbell Industrial Park businesses and to nearby sensitive receptors in event of an emergency. Planned Changes to Improve Safety Through the process of developing and implementing Process Safety Management and Risk Management Programs The Gas Company has identified and implemented numerous improvements to its pro gram and facility. Through the cycles of hazard analysis, audits, management of change and other program items potential improvements are continuously identified, prioritized and resolved. Some of the items that will be addressed in the upcoming months include: -Improved procedures for maintenance tasks -Improved maintenance and inspection programs -Instrumentation improvements for better process control -Equipment additions and upgrades -Improved emergency response procedures |