Oklahoma City Product Supply Center - Executive Summary |
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The Oklahoma City Product Supply Center (Hattie Street) is a food distribution warehouse that contains refrigerated areas for perishable items. The refrigerated areas of the warehouse are cooled by an anhydrous ammonia refrigeration system. Anhydrous ammonia, a substance regulated by EPA, is one of the most economical refrigerants available. However, the properties of ammonia makes it necessary to observe certain safety precautions while operating the refrigeration system to prevent employee exposure, and to reduce the threat of exposure to nearby members of the community. The Oklahoma City Product Supply Center (Hattie Street) has chosen to follow the EPA's Chemical Accident Prevention Rule, Program Level 3, to prevent a release of ammonia from the refrigeration system. The amount of ammonia estimated to be contained inside the cooler refrigeration system is 12,000 pounds. The Oklahoma City Product Supply Center (Hattie Street) complies with EPA's Accidental Release Prevention R ule, and applicable state codes and regulations to prevent a catastrophic release of ammonia. The ammonia refrigeration system also has been constructed in accordance with the International Institute of Ammonia Refrigeration guidelines (IIAR). The operators of the systems are required to complete a training and certification program to operate the ammonia refrigeration system. The Accidental Release Prevention Program does not guarantee against an accidental release. An offsite consequence analysis was completed using a computer model to simulate a release of the ammonia from the refrigeration system. The worst case scenario considered the loss of the total charge of 12,000 pounds of anhydrous ammonia in the refrigeration system over a 10-minute period. The analysis showed that the ammonia vapor could travel approximately 3,344 yards, or 10,032 feet. There are public receptors (residences, schools, recreational areas, and industrial/commercial buildings) in the affected radius. There are approximately 13,147 residents that could be affected in the identified radius. There are no environmental receptors in the potentially affected area. The alternative release scenario, which is the most likely scenario, considered a release of ammonia from a broken line inside the building. A release of 2,000 pounds of ammonia over a 10-minute period was considered. The computer model showed that the ammonia vapor could travel approximately 369 yards, or 1,107 feet. There are public receptors (industrial/commercial buildings) in the potentially affected area. No administrative controls or mitigation measures were used to limit the chemical release distances for either scenario. The Oklahoma City Product Supply Center (Hattie Street) has an established Emergency Action Plan to respond to accidental ammonia releases. The plan was developed in accordance with 29 CFR 1910.38 Emergency Action Plan. The plan requires Fleming associates to exit the facility during a fire o r ammonia release to a safe area. The emergency agencies will be notified of the emergency. The emergency agencies will notify any potentially affected neighbors. Fleming maintenance associates on the emergency response team have been trained to respond and assist the local emergency agencies with anhydrous ammonia emergencies at the Oklahoma City Product Supply Center (Hattie Street). The plan also addresses natural hazard emergencies, fires, bomb threats, civil disturbances, and utility outages. This location has not experienced an ammonia release in the past 5 years. The Oklahoma City Product Supply Center (Hattie Street) wanted to evaluate the potential failures of the refrigeration system, and if the safeguards were sufficient to prevent a catastrophic release of ammonia. A Process Hazard Analysis was completed on the refrigeration system on August 17-20, 1998. Planned changes to improve safety resulting from this analysis are documented in the Process Hazard Analysis repo rt in the Chemical Accident Prevention Program. Also, the guidelines from the International Institute of Ammonia Refrigeration (IIAR) will be followed where applicable, to manage the refrigeration system. |