Kennewick Plant - Finley Area - Executive Summary |
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1. Accidental Release Prevention and Emergency Response Policies Unocal's Kennewick Plant is comprised of the three neighboring areas, Kennewick, Hedges, and Finley Areas. The Kennewick Plant along with the West Sacramento Plant, Rivergate, and Fresno Terminals constitute the integrated operation known as Unocal Agricultural Products Group's West Coast Facilities. The Unocal Kennewick Plant - Finley Area handles anhydrous ammonia and aqua ammonia which are considered hazardous materials and are regulated substances under the Federal Accidental Release Program (ARP) and are considered in this Risk Management Plan (RMP). The properties of these chemicals make it necessary to observe safety precautions in handling them to prevent human exposure, and to reduce the threat to the facility's workers and nearby members of the community. It is the facility's policy to adhere to all applicable Federal and State of Washington rules and regulations. Safety depends upon the safe procedures us ed to handle anhydrous ammonia and aqua ammonia; the safety devices and systems designed and constructed into the facility; and the training of the pertinent personnel. 2. Description of the Stationary Source and Regulated Substances Handled The majority of the anhydrous ammonia supply for the Kennewick Area is produced by the Finley Area Ammonia Plant and transferred to the Kennewick Area via pipeline. The manufacturing of ammonia uses basic principles of chemistry with readily available ingredients. Natural gas, water and air are the raw materials used to manufacture anhydrous ammonia at the Finley Area. Natural gas from the Northwest Pipeline provide fuel and feedstock. Water is supplied from the Columbia River for steam and ambient air is used as a source of nitrogen. With the aid of catalysts, heat exchangers and compressors, the natural gas is reformed into hydrogen and combined with nitrogen to yield ammonia which is then liquefied and stored for transport by pipeline to the Kennewick Area to produce nitrogen based fertilizers. Water is also added to anhydrous ammonia to produce aqua ammonia. There are two Ammonia Plants at the Finley Area, #1 Plant and #2 Plant; however, in the compression and synthesis processes, their gas streams merge to form one gas stream. 3a. Worst Case Release Scenario The Worst Case release scenario for interconnected equipment must consider each quantity of a regulated substance handled on site in a single vessel at any time above the threshold quantity, taking into account administrative controls. In addition, smaller quantities of the regulated substance handled at higher process temperature or pressure must be considered if such a scenario would result in a greater distance to an end-point beyond the stationary source boundary. The Worst Case scenario did not consider any administrative control to limit the amount of regulated substance in any subject vessel. The ammonia storage sphere C-510A with anhydrous ammonia yields the greatest distance to the end-point and is designated as the Worst Case release scenario. The distance to the end-point of 200 ppm for the Worst Case scenario, determined by RMP*COMP, is beyond the boundaries of the stationary source. 3b. Alternative Release Scenarios The Alternative Release scenario for anhydrous ammonia, as submitted, is the most frequent credible release scenario with the greatest distance to toxic endpoint. This is the continuous release of liquid anhydrous ammonia from a railroad car loading arm due to sudden disconnection. This results in the release of gaseous ammonia at the rate of 3,550 lb/min for 1 minute. The distance to the end-point of 200 ppm for the Alternative Release scenario for the anhydrous ammonia, determined by RMP*COMP, is beyond the boundaries of the stationary source. The Alternative Release scenario for aqua ammonia, as submitted, is the most frequent credible release scenario with the greatest distance to toxic endpoint. T his is the continuous release of the 25% liquid aqua ammonia from PSV 1-059 on the shell side E-166 due to overpressure. This results in the release of gaseous ammonia from the 77 degrees Fahrenheit aqua ammonia at the rate of 2,019 lb/min for 45 minutes. The distance to the end-point of 200 ppm for the Alternative Release scenario for aqua ammonia, determined by RMP*COMP, is beyond the boundaries of the stationary source. 3c. Administrative Controls Administrative controls are in place to prevent accidental releases. Additional administrative controls to limit the distances for each reported scenario exist to restrict to a minimum the amount of anhydrous ammonia and aqua ammonia if an accidental release were to occur. These administrative controls are inherent in the operational procedures for the equipment, processes and systems that use anhydrous ammonia and aqua ammonia, as well as the training provided to the operators of these processes and systems. 3d. Mitigation Measure s Mitigation measures for each reported scenario exist that restrict the amount of anhydrous ammonia and aqua ammonia released to a minimum, if a release were to occur. The mitigation measures are based upon the design, inspection, testing, and maintenance of the processes, systems and related equipment and components that use anhydrous ammonia and aqua ammonia. 4. General Accidental Release Prevention Program and Chemical Specific Prevention Steps The facility complies with all applicable federal and state codes and regulations. There are safety meetings and safety training. The Process Safety Management (PSM) program is one part of the comprehensive loss control program system implemented at the facility for the anhydrous ammonia and aqua ammonia processes and systems. The implementation of PSM, safety related Administrative Procedures and Safe Work Practices represent the facility's main active commitments to an accidental release prevention program. 5. Five-Year Accident Hi story There have been no accidents at the subject stationary source to be reported in this RMP in the previous five-year history of the facility. 6. Emergency Response Program The details of the Emergency Response Program for the anhydrous ammonia and aqua ammonia processes at the Finley area are contained within two documents. One is the Emergency Preparedness Action Plan that contains all of the emergency response program elements. It is intended to be a compliance, reference and training guide. The other is a field guide for response actions based on the chemical involved. It is intended to be used by the response personnel while responding to an emergency event. The Emergency Response Program incorporates public notification and alert systems, as well as alerting personnel at the facility to evacuate the facility and await the arrival of responders from the Benton County Fire Department at the evacuation assembly location, if a release occurs that causes the evacuation to be initiated. 7. Planned Changes To Improve Safety There is one commitment made under the Covered Process Hazard Analysis element of the Process Safety Management (PSM) program, in the anhydrous ammonia system, to be completed. The action item, No. 896, is to modify the firewater system for vapor supression to reduce pressure fluctuations. Expected completion is 09/30/1999. Current applicable codes and regulations are reviewed as part of the PSM to determine if other commitments need to be made to achieve increased operational safety for the regulated anhydrous ammonia and aqua ammonia processes and systems. These commitments will be prevention and mitigation measures for accidental releases of the regulated substances. |