AES Hawaii Inc. - Executive Summary |
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N:\COMMON\RMP\RMP-DRAFT2\SEC1-3A.RTF 6/2/99 1-1 SECTION 1 EXECUTIVE SUMMARY EPA's Accidental Release Prevention Rule, which is authorized under 112(R) of the Clean Air Act (CAA), requires that facilities that have covered processes establish Risk Management Programs to reduce the risks of accidental release of toxic or flammable materials and establish emergency response procedures in the event of an accident. This Risk Management Plan summarizes the efforts that this company has undertaken to establish a Risk Management Program. Anhydrous ammonia is the only chemical used at the AES Hawaii facility that is above the RMP threshold amount. The onsite maximum storage quantity of the liquid anhydrous ammonia tank at the AES Hawaii plant is 109,000 pounds, which is above the 10,000 pound RMP applicability threshold. The AES Hawaii plant does not use any other chemicals or flammable materials in excess of threshold quantities covered by RMP requirements. A management system will be in place at the facility to oversee implementation of the facility's Risk Management Program. This management system is considered one of the most important elements of this facility's Risk Management Program, as its goal is to ensure that lines of authority and responsibility are clearly defined, helping to ensure that all elements of the Risk Management Program are implemented. At the AES Hawaii Facility, the person who has the overall responsibility for the Risk Management Program is the environmental coordinator. The facility also participates in emergency response activities with the Campbell Local Emergency Action Network (CLEAN). CLEAN has developed an Emergency Management Plan that provides supplemental guidance and information to emergency response personnel, local residents, and busi ness based on the specific operations in and around Campbell Industrial Park (CIP). The plan addresses emergency planning, public health and safety. The AES Hawaii facility generates steam and electricity at 91- 086 Kaomi Loop, Hawaii 96707. The Plant is located near Barber's Point, within the area known as Campbell Industrial Park, which is on the Island of Oahu about 30 miles west of Honolulu. Electricity generated by the facility is supplied to Hawaiian Electric Company, and steam is sold to the nearby Chevron USA oil refinery. The plant has two Circulating Fluid Bed (CFB) coal-fired boilers and one steam turbine. The CFB boilers use a clean coal technology that minimizes emissions of sulfur dioxide, nitrogen oxides. The boilers use limestone that reacts with the sulfur in the coal to reduce sulfur dioxide emissions. The nitrogen oxides emissions are reduced by two factors: the relatively low boiler operating temperatures and the a ddition of anhydrous ammonia to the boiler flue gas that reacts with the nitrogen oxides to produce harmless nitrogen gas and water vapor. Ammonia safety considerations have been incorporated into the construction of the ammonia system. The ammonia tank is secured to the ground and has cathodic protection. The tank has relief valves at the top of the tank. Thus, overpressurization of the tank would primarily involve the venting of gas in the upper part of the tank. The vapor lines from the tank to the boiler area are buried to reduce potential releases from this piping. Loading and unloading valves, the tank and tanker truck are equipped with automatic shut-off valves in the event that flow through the valves exceeds design criteria. Therefore, in the event of a loading hose failure, the flow of ammonia would be automatically terminated. The facility also has a monitor located in the ammonia system process area tha t detects leaks and triggers an alarm. This facility maintains a Prevention Program at the facility that minimizes the possibility of any accidental release from the ammonia system. The prevention program incorporates a mechanical integrity program, regularly scheduled maintenance, daily visual operational checks of equipment, and employee training in proper operating procedures and emergency response. AES Hawaii has designed a Mechanical Integrity Program for ammonia in accordance with 29 CFR 1910.119(j). The purpose is to verify that critical process equipment is designed, installed, maintained properly, and operates correctly. In accordance with this program, the ammonia processes and equipment must be constructed, installed, and maintained in order to minimize the risk of releases of the highly hazardous chemicals. The mechanical integrity program at AES Hawaii includes identifying and categorizing equipment. Inspecting and testing of instrumentation and documenting maintenance procedures; training of maintenance personnel; establishing criteria for acceptable test results; documenting test and inspection results; and documenting manufacturer information for equipment and instrumentation. The facility performs a system integrity check every five years for the ammonia storage tank and all associated hoses/lines. The most recent integrity evaluation was performed in May 1998. As part of this evaluation, all emergency relief valves and storage tank loading/unloading valves and hoses were replaced. The equipment is maintained in accordance with manufacturer specifications, and applicable ANSI, and ASME engineering codes. A computer database generates work orders to identify when such maintenance needs to be implemented. Once, each 12-hour period, operators visually observe the equipment for signs of potential malfunction. Alarms an d interlocks are checked on a monthly basis. All new employees, regardless of position, are given a safety walk of all areas of AES Hawaii. This walk through includes the ammonia system. Special emphasis is placed on the nature of the anhydrous ammonia and actions of all personnel in case of an ammonia problem (i.e. leak). All persons hired who are responsible for operations of the ammonia system are given full classroom training before they are allowed to work on, operate or otherwise manipulate or affect the ammonia system. The classroom course includes detailed instruction on the ammonia system, including the physical aspects of ammonia, operating the ammonia system, and casualties involving the ammonia system. They are trained regarding the hazards and safety precautions to be observed for the ammonia system. In addition, annual refresher training is required. The plant has a current "Disaster and Emergency Plan". All employees have bee n trained in the plan, and the plan is reviewed frequently to verify that it is current with plant operating practice. The plan contains emergency response procedures (ERP) which include actions for evaluating the severity and controlling releases of hazardous materials including ammonia. A list of the agencies that must be notified is included in the plan to assure that the public is properly notified in the event of an emergency. AES Hawaii has performed a Hazard and Operability (HAZOP) Analysis that evaluated all potential hazards for the facility. The HAZOP study was performed according to the procedures described in "Guidelines for Hazard Evaluation Procedures; Center for Chemical Process Safety" published by the American Institute of Chemical Engineers, New York. The HAZOP was performed by a team of technical experts in the system's process, engineering, design, operations maintenance, and safety. The ammonia system was divided into sections or segments and assigned a node number. Each node was evaluated for deviations using guide words such as "no flow", "high pressure", etc. The cause and consequence of a guide word applied to a node were evaluated to determine and identify deviations and/or hazards that can result from application of a guide word to the node. Each identified consequence was assigned a relative risk rank based on the severity of the consequence and anticipated frequency. The team then discussed corrective actions which were recorded and implemented or are in the process of being implemented. A Hazard Assessment is also included in this Risk Management Plan. It presents the potential offsite impacts for the postulated worst-case alternative release scenario for the ammonia system. The worst case scenario required by the EPA assumes that the entire content of the ammonia storage vessel is released over a 10-minute period. It is important to note that the likelihood of the worst-case scenario is extremely low. Additionally, the meteorological parameters assumed for the worst-case scenario are low wind speed and high stability, thus resulting in a very conservative analysis. The alternative case scenario is based on a transfer hose failure or a pipe leak through a 1-inch hole. The entire content of the ammonia system is assumed to release over a 60-minute period. The zone of impact in this case is approximately 0.62 miles and would primarily affect business in CIP. The alternative scenario also is conservative. AES has implemented these various analyses and training programs to prevent and prepare for an emergency release. To date, this facility's Five Year History (and entire history of the plant) does not include any accidental releases from the ammonia system which resulted in deaths, injuries, or significant property damage onsite, or known offsite d eaths, injuries, evacuations, sheltering in-place, property damage, or environmental damage. |