The Pillsbury Company - Chanhassen (Ammonia) - Executive Summary |
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Executive Summary The Risk Management Program (RMP) includes an Executive Summary as required by 40CFR 68.155. This Executive Summary includes a discussion of the various Risk Management Program elements as follows: 1. Accidental release prevention and emergency response policies 2. Stationary source activities 3. Regulated substances handled 4. Worst-case and alternative release scenarios 5. General and chemical-specific accidental release prevention program 6. Five-year accident history 7. Emergency response program 8. Planned changes to improve safety 9. Summary 1. Accidental Release Prevention and Emergency Response Policies It is Pillsbury's policy to comply with the all of the requirements of the EPA's Accidental Release Prevention Program regulation and all applicable Federal and state rules and regulations. The plant has developed a Risk Management Program that includes a description of the management system, the Offsite Consequence Analysis (OCA), the five-year accident history, the Prevention Program elements, and an Emergency Response Program. The plant has also developed a Process Safety Management (PSM) Manual to comply with OSHA PSM requirements. 2. Stationary Source Activities The plant located to the west of the City of Chanhassen in Carver County. The plant was built in 1989, and acquired by Pillsbury in 1992. The plant produces baked or par-baked products, raw cookie dough, frozen puffed pastries and frozen muffin batters. The ammonia refrigeration process is used to cool and freeze the finished goods. 3. Regulated Substances Handled The ammonia for the refrigeration system at the Chanhassen Plant is a regulated substance under the EPA's Risk Management Program rule. The ammonia system is a closed loop which recirculates and reuses the same material. Infrequent makeup to the system is only to replace material lost due to maintenance activities and a small intermittent purge. The system consists of compressors, receivers, evaporators and condensers and has a maximum intended inventory of 94,000 pounds of ammonia. Ammonia leak detectors have been located throughout the ammonia areas. All ambient detectors trigger a leak alarm. 4. Worst-Case and Alternative Release Scenarios For the worst case and alternative release scenarios, the EPA Model Risk Management Program and Plan for Ammonia Refrigeration (May 1996), the International Institute of Ammonia Refrigeration (IIAR) Risk Management Guidelines for Ammonia Refrigeration (1998) and the EPA Risk Management Program Guidance for Ammonia Refrigeration (November 1998) were used for guidance. The Ammonia Guidance tables were used to derive the hazard distances for worst-case and alternative release scenarios. Releasing the contents of the Engine Room #2 Intercooler which can contain up to 34,000 pounds (83.5% at 18F) of ammonia represents the worst-case scenario. The resulting distance to the endpoint extends offsite, and public receptors are within the distance t o the endpoint. The alternative release scenario was chosen as a quarter-inch hole, which would be representative of a pump seal leak or a gasket rupture. The resulting distance to the endpoint also extends offsite, and public receptors immediately adjacent to the facility are within the distance to the endpoint. Discussion The results included in this analysis indicate that the worst-case release for the ammonia process can extend offsite and reach public receptors. However, it is important to emphasize that a worst-case release is extremely unlikely to occur because of the many safety features inherent in the design and operational systems for the plant. On the other hand, the alternative release scenario is based on credible assumptions. The alternative scenario was selected from a number of possible scenarios, based on their potential to reach offsite. As mentioned in the Ammonia Model RMP, the alternate ammonia scenario would be representative of a gasket or valve packing. 5. Prevention Programs For the Chanhassen Plant ammonia system, Pillsbury followed the ANSI/IIAR 2-1992 Standard for Equipment, Design, and Installation of Ammonia Mechanical Refrigeration Systems and implemented an RMP Program 3 Prevention Program which is equivalent to the OSHA Process Safety Management (PSM) program. This is one of the most important ways for preventing ammonia releases and for minimizing the impacts of any release that does occur. Some of the key elements of the Prevention Program are summarized below. Process Safety Information(PSI) - A comprehensive set of process safety information has been compiled for the ammonia system. The PSI includes data on the chemicals, the equipment and the technology of the process. Process Hazards Analysis (PHA)- An initial PHA was conducted to satisfy the PSM requirements in 1994 and was revalidated in 1999. Recommendations made by the PHA team to improve the safety of the systems are being addressed. Operating Procedures - An Operations and Maintenance Manual provides detailed written operating procedures for the ammonia system and for safe work practices. Training - Training is provided to each operator and maintenance person before they are certified to operate the system. Maintenance - All of the covered ammonia equipment is included in the Eden Prairie preventive maintenance program. Equipment inspections, testing and preventive maintenance activities are performed following a structured schedule according to IIAR Bulletin 109. Management of Change (MOC) - An MOC procedure has been developed and is implemented for all changes made to the ammonia system, including the safety systems. Pre-startup Review (PSR)- Pre-startup reviews are conducted whenever a change results in a change to the PSI. Checklists are used to direct the PSR process. The checklists are used to ensure that all essential elements of the prevention program (i.e., engineered systems and documentation) were in place prior to start up. Compliance Audits - An initial compliance audit was conducted in 1995 and another in 1998. All findings from the audits have been addressed. Incident Investigation - The Pillsbury Company routinely investigates any ammonia related incident or accident that occurs at the Chanhassen Plant. An Incident Investigation procedure has been developed to help the investigation team determine the root cause of an incident and to help them develop measures to prevent recurrence. Employee Participation - An employee participation program (for safety and risk management) is in place and training in PSM has been conducted for all affected employees. Employee involvement in PHA studies and review of operating procedures is an important way in which employees take and retain ownership of the risk management programs. Hot Work Permit Program - A hot work permit program is being used at the Chanhassen Plant whenever hot work is conducted in and around the ammonia systems. Contractor Safety - Contractor safety procedures are in place and include reviews of contractor performance and the inclusion of safety performance and programs in selecting contractors for work on or adjacent to the ammonia process. 6. Five-Year Accident History There have been no releases of ammonia in the last five years from the plant that meet the RMP accident criteria. 7. Emergency Response Program The plant has an emergency response program which is described in the Emergency Response Plan. This plan includes procedures for evacuations, notifying response agencies and adjacent businesses, emergency equipment list with maintenance schedule, and procedures for responding to any release that may occur. The plan also includes first aid procedures for toxic exposures to ammonia. The ERP is coordinated with the Chanhassen Fire Department and the Carver County Emergency Management. The facility has conducted risk management plan communication meetings with employees and has notified immediate offsite receptors. A public communications meeting was held on May 1, 1999 in cooperation with the Chanhassenn Fire Department and the Carver County Emergency Management. 8. Planned Changes to Improve Safety All recommendations from previous PHAs, MOCs, and PSRs are being addressed. However, it is Pillsbury's policy to review operating, maintenance and emergency response procedures on a routine basis to ensure they are always applicable. This continuous review process does generate further recommendations for improved safety during the course of operations, but these measures are typically addressed in a very short time frame. 9. Summary The design of the ammonia system and the implementation of the PSM and RMP programs provide a high level of assurance that the hazards and risks associated with the use of ammonia are being managed in an appropriate manner. The likelihood of a release is minimized through the implementation of these programs. Pillsbury has developed an Emerge ncy Response Plan which is coordinated through the local response agencies. |