Anderson Erickson Dairy Company - Executive Summary |
|
ANDERSON ERICKSON DAIRY CO. DES MOINES, IOWA Background Data In accordance with Title 40 of the Code of Federal Regulations Chapter 68 (40 CFR 68) promulgated by the Environmental Protection Agency (EPA), Anderson Erickson Dairy Co. (AE Dairy) submits this Risk Management Plan (RMP) for operations at their Des Moines, Iowa facility. The operations at AE Dairy include the processing of fluid milk and dairy products for public consumption, packaged under the familiar Anderson Erickson Dairy brand name. AE Dairy has been in operation at this facility for over 60 years providing quality products and over 330 jobs to the local community. Accidental Release Prevention and Emergency Response Policy AE Dairy is committed to protecting the health of its employees, the surrounding community, and the environment. It is AE Dairy's policy to maintain a safe and healthy workplace, protect the environment, and comply with all applicable regulations, including 40 CFR 68 and the Occupational Safety and Health Administration's (OSHA's) Process Safety Management (PSM) regulation, 29 CFR 1910.119. Stationary Sources and Regulated Substances To ensure the quality of AE Dairy's final products, refrigeration is necessary to maintain the low temperatures required for the food processing and storage areas of the plant. These requirements are promulgated and monitored by the United States Food and Drug Administration, the Iowa State Department of Agriculture and the Iowa State Department of Health. In addition, the refrigeration system is utilized to operate large coolers for product storage. To achieve this, AE Dairy uses anhydrous ammonia, the 112(r) regulated substance, as the refrigerant in the cooling system. The ammonia refrigeration system maintains the 120,000 sq. ft. facility within the required range of operating temperatures and provides the cooling for all stored products. Anhydrous ammonia is a standard refrigerant for the food industries and widely used thro ughout the country. The refrigeration system at AE Dairy consists of receiver vessels, compressors, evaporators, condensers, chillers and piping. The system can contain a maximum amount of 27,000 pounds of anhydrous ammonia at any time during the course of the year. Worst Case Release Scenario As required by 40 CFR 68 Subpart B, AE Dairy has evaluated a worst-case release scenario for anhydrous ammonia using the parameters specified by the EPA. The worst-case release scenario is defined as the release, over a 10-minute period, of the entire contents of the largest vessel or pipe in the facility's system. Based on the design of AE Dairy's refrigeration system, the worst case release scenario would involve the rupture of the Controlled Pressure Receiver, which is the largest single vessel in the system. The Controlled Pressure Receiver can contain approximately 12,168 pounds of ammonia when filled to 80% capacity, which is the maximum fill capacity allowed by AE Dairy. The Cont rolled Pressure Receiver, like all other major vessels in the system, is located inside a building. The room in which the Controlled Pressure Receiver is located has two self-closing, interior doors leading into other sections of the building and no exterior doors or windows. While the room provides passive mitigation for a release, the room is equipped with a ventilation fan that exhausts to the outside atmosphere. The release of the entire contents of the Controlled Pressure Receiver, through this exhaust fan, is the basis for the worst-case scenario. Using the equations in Chapter 4 of the EPA's RMP Guidance for Ammonia Refrigeration and the RMP*Comp computer program, the maximum distance to the specified "endpoint" was calculated. This is a conservative distance, established by the EPA, at which it is expected that a person could be exposed to the chemical for an hour without suffering irreversible health effects. The distance to the endpoint, calculated for the worst-case re lease scenario, includes offsite receptors. The worst-case release scenario was developed following EPA regulations and is not considered by AE Dairy to be a likely release scenario for the facility. During normal operations, AE Dairy maintains the Controlled Pressure Receiver at no more than 50% of capacity. The receiver would only have the potential to be filled to 80% of capacity when receiving an ammonia charge or during a pump-down operation. The Controlled Pressure Receiver has been operated in pump-down mode only two times in the last seven years. Ammonia charging is only performed on an as needed basis, potentially occurring only a few times each year. Alternative Release Scenario A more realistic release scenario (alternative release) was developed by AE Dairy taking into consideration the 60-year history of operational experience and the hazards identified in the process hazard analysis (PHA) conducted to ensure that AE Dairy hazards are identified and minimized. T he analysis was conducted in accordance with OSHA's Process Safety Management regulations contained in 29 CFR 1910.119. The alternate release scenario identified by AE Dairy involves damaging a = inch diameter pipe, resulting in the release of liquid ammonia. When considering the potential alternate release scenarios, piping routed to, and installed on, equipment located outside the buildings was considered first. In developing the release parameters of this alternative scenario, AE Dairy considered piping and equipment located in areas where vehicle traffic, personnel foot traffic, and work-related activities were likely to occur. The resulting scenario involves damage to the sight column of a tube and shell chiller located outside of the warehouse. The chiller is located in an area traveled by personnel and vehicle traffic; making damage to the equipment by objects or vehicles a credible scenario for consideration. Other considerations include a full flow liquid release from the leaking pipe and a conservative estimate of the response time necessary to control the release. Using the equations in Chapter 4 of the EPA's RMP Guidance for Ammonia Refrigeration and the RMP*Comp computer program, the maximum distance to the specified "endpoint" was calculated. This is a conservative distance, established by the EPA, at which it is expected that a person could be exposed to the chemical for an hour without suffering irreversible health effects. The distance to the endpoint, calculated for the alternate case release scenario, includes offsite receptors. Accidental Release Prevention Program To prevent and mitigate accidental releases of anhydrous ammonia, AE Dairy has implemented several precautionary measures including process and equipment controls, operating procedures, preventive-maintenance programs, employee training, and audit programs. In addition, the ammonia refrigeration system itself is designed and constructed in accordance with ANSI/IIAR 2-1992 Standard for Equipment, Design, And Installation of Ammonia Mechanical Refrigerating Systems. AE Dairy has also developed and implemented a PSM program pursuant to OSHA regulations and as such, has evaluated the refrigeration system for the potential to release anhydrous ammonia. Some of the controls installed to prevent catastrophic releases of ammonia include process equipment (pressure relief valves, check valves, backup pumps, and manual shutoffs), automated controls (automatic shutoffs, ammonia leak detection system, and electrical distribution system grounding) and emergency power supply. AE Dairy has developed standard operating procedures for all employees and contractors that have contact with the ammonia refrigeration system. These procedures incorporate safety measures to prevent employee injury, equipment damage, and accidental releases. The procedures were developed by a team consisting of personnel from operations and maintenance, plant engineering, and AE Dairy's refrigeration contractor. Pursuant to written management of change procedures established by AE Dairy, any changes to the operating procedures are to be communicated to affected employees. AE Dairy understands that maintaining the refrigeration system in good working order is essential to preventing accidental releases; therefore AE Dairy has implemented a preventative maintenance program. The preventative maintenance program is scheduled, documented and managed to ensure that regular maintenance occurs on the system. Also, to ensure the mechanical integrity of critical refrigeration system components, equipment inspections are performed. To ensure that the control measures at AE Dairy are effective in maintaining the safe operation of the plant, regularly scheduled audits are performed on the ammonia refrigeration system: 7 In accordance with the PSM program, AE Dairy conducts detailed PSM compliance audits every three years. Each audit incorporates review of process safety in formation, process hazard analysis, operating procedures, training programs, system mechanical integrity, management of change, pre-start up safety review procedures, compliance audit procedures, incident investigation procedures, employee participation programs, hot work permit procedures, and contractor safety procedures. 7 In addition, the facilities and records of AE Dairy are inspected and audited by the following: 7 The Iowa State Department of Agriculture every three months. 7 The Iowa State Department of Health every year. 7 The City of Des Moines Fire Department every year. 7 The United States Food and Drug Administration every two years. 7 AE Dairy's insurance carrier also conducts independent loss prevention audits every year. Five-Year Accident History Over the last five years, AE Dairy has not experienced an accidental off-site release of anhydrous ammonia from the ammonia refrigeration system. Emergency Response Program The AE Dairy facilities are included in the written community emergency response plan developed by the Polk County Local Emergency Planning Commission. In addition, AE Dairy has developed an emergency action program designed to protect both employees and the community in the event of an ammonia release, fire, or other emergency. This program is fully described in a document entitled, "ANDERSON ERICKSON DAIRY - EMERGENCY ACTION PLAN". Included in the document are measures to be taken by AE Dairy including emergency notifications, on-site and off-site coordination, ammonia release procedures and evacuation procedures. To assure that the local governmental response agencies are familiar with AE Dairy's emergency response procedures, copies of the program have been submitted to the following local agencies: 7 City of Des Moines Fire Department 7 Polk County Local Emergency Planning Commission In addition to the above local response agencies, AE Dairy has arranged for emergency response assistance with a local refrigeration contractor knowledgeable in the facility layout and the design and operation of the ammonia refrigeration system. In the event of an anhydrous ammonia release with off-site effects, the general public will be warned using the following methods: 7 Police and fire vehicles equipped with public address systems, 7 Door-to-door notification of residents, and 7 Broadcast message via the Polk County Emergency Broadcast System, if necessary. Continuing Efforts to Improve Safety As part of AE Dairy's continuous efforts to improve the performance of its safety systems, several changes are planned at the facility to improve safety and prevent anhydrous ammonia releases. These changes are scheduled to be implemented by the end of calendar year 1999 and include equipment upgrades, additional preventive maintenance procedures, and additional safety systems. |