Kraft Foods Inc. - Executive Summary |
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1.0 Release Prevention and Emergency Response Policies The Kraft Foods facility in Bentonville, Arkansas has an excellent record in preventing and minimizing releases of anhydrous* ammonia. This facility has a thorough emergency training program for on-site emergency responders. This facility has implemented an electronic preventive maintenance system. This is a system that uses a real time database to track training and inspection dates and issue reminders to responsible groups. The emergency response policies at this facility ensure that there is emergency response coverage, 24 hours - 7 days per week. There are also adequate provisions for coordination with outside agencies, such as with the Bentonville Fire Department and the Benton County Emergency Government (LEPC), in the event of an emergency. Responders are on site most of the time. During periods when there are no on site responders, plant employees have been instructed to call 911 in the event of an emergency. The Ben tonville Fire Department is the primary responder in either case. At least one person per shift has been trained to assist the fire department with the response to an ammonia release. *From this point in the Executive Summary, anhydrous ammonia will be synonymous with ammonia. 2.0 Process Description and Regulated Substances At this location Kraft Foods manufactures cheese and whey products from milk. The SIC code for the primary process at this facility is 2022. The NAICS code for this facility is 311513. Many areas of the plant are refrigerated to preserve the products. Some of these areas include: raw material storage, process equipment, filling and finished product storage. Kraft Foods has one regulated substance under 40 CFR 68, anhydrous ammonia, at this location. Ammonia is used as a cooling agent in the refrigeration of the milk and cheese products in the various areas described above. The ammonia threshold for triggering applicability to 40 CFR 68 is 10,000 pounds. The quantity of ammonia stored on-site is approximately 16,033 pounds. Thus, 40 CFR 68 is applicable to Kraft Foods in Bentonville, AR. 3.0 Worst-case and Alternative Release Scenarios The ammonia refrigeration system has associated hazards that can potentially affect on-site employees and the general public if there is a release from the system. Although the alternative release scenario is more probable, the US EPA requires one worst-case and one alternative release scenario be reported for each regulated chemical. Described below are the associated hazards and the worst-case and alternative release scenarios for each regulated chemical. Ammonia Ammonia is classified as a Group 2 Refrigerant per ASHRAE Standard 34-1989. The dominant characteristic of this chemical is its toxicity. It is a self-alarming chemical by its distinctive pungent odor. Due to this odor, persons exposed to ammonia vapor will not voluntarily stay in areas of even small concentrations. Ammonia is flammab le in a very narrow and high range of concentration with a high ignition temperature. It is not poisonous, but it is corrosive to human tissue. Ammonia is readily absorbed into the moisture of the skin, and at high concentrations can cause severe burns. The risks to persons in an accidental release of ammonia include: 1. Irritation of respiratory tract, 2. Corrosive attack of skin and other tissue, 3. Freezing of skin and other body tissue when contacted by liquid ammonia. Below is a description of the release scenarios for ammonia and their off-site consequences: Worst-case scenario - The largest potential release of ammonia will occur with a one inch diameter puncture in the high pressure receiver during system pumpout. The receiver is located outside of the plant by the northeast wall. Taking the specific definition of the worst-case from 40 CFR 68.25, the largest quantity of ammonia that can be stored in a vessel is in the high pressure receiver during system pumpout. The total quantity of ammonia that can be stored in the high pressure receiver is 15,034 pounds without administrative controls. It is assumed that the entire quantity in the receiver, 15,034 pounds, is released to the atmosphere in 10 minutes. Under Section 68.25(c)(1), a regulated substance such as ammonia, which is normally a gas at ambient temperature and handled as a liquid under pressure, shall be considered to be released as a gas over a 10 minute period. Thus, ammonias physical state in the worst-case release is a gas. The ammonia worst case scenario was modeled using SLAB (June 1990 version) to obtain the distance to endpoint. The endpoint is defined by the US EPA as the Emergency Response Planning Guideline, Level 2 (ERPG-2) which was calculated to be 1.06 miles. The ERPG-2 was developed by the American Industrial Hygiene Association and is applicable to human exposures for up to one hour. The ERPG-2 is intended to protect individuals from health threatening or escap e impairing injury and is not generally considered fatal. SLAB is a computer model developed (1983) by Lawrence Livermore Laboratories and sponsored by the Department of Energy (DOE) and EPA. SLAB is a dense gas model (also models neutrally-buoyant and includes lofting of a cloud if it becomes lighter than air) for various types of releases including a ground-level evaporating pool, an elevated vertical and horizontal jet, and an instantaneous volume source. The model solves the conservation equations of mass, momentum, energy, and species. It can simulate continuous, finite duration, and instantaneous releases. Rural dispersion coefficients (0.4 surface roughness) were used during modeling runs for the Bentonville facility in accordance with Appendix W to Part 51- Guidelines on Air Quality Models Section 8.2.8. The estimated affected residential population is 1,863 people. The types of affected receptors are listed in the Data Elements section. Alternative Release Scenario - The worst-case release is less likely to occur than the following scenario: Alternative Release Scenario Description The alternative release scenario that meets both selection criteria is an ammonia release from the Pressure Relief Valves (PRVs) on the high pressure receiver (dual relief valves assumed 2 PRVs releasing at the same time) which are located approximately 160 ft from the property line. The actuation of the PRVs will produce a horizontal jet release. There is no applicable administrative controls or passive mitigation associated with the PRVs. Active mitigation is defined as human intervention. It is assumed that the PRV will be deactivated by human intervention 10 minutes after the start of the release. Our calculations showed that the ammonia vapor release rate is 50.91 lb/min. The US EPA Risk Management Program and Plan for Ammonia Refrigeration Table A-1 was used to determine the distance to the ERPG-2 endpoint of 0.141 miles. The estimated effected residential population is 148 people. 4.0 General Accidental Release Prevention Program and Chemical-Specific Prevention Steps This facility has developed an OSHA PSM program for their ammonia refrigeration system. Ammonia falls under the RMP Program 3 prevention program, which is identical to the OSHA PSM program. EPA has stated that if the process is in compliance with OSHA PSM, it is in compliance with RMP Program 3. Thus, Krafts ammonia PSM has been reviewed and determined to be complete for the RMP document. There are several aspects of the prevention program that are key: 1. The Utility Service Area design (USA) serves as an excellent safeguard for plant personnel because it greatly reduces the amount of ammonia piping inside occupied rooms. Since most of the pipe work is out of the way of people and the machinery and so there is less of a chance of an ammonia release. 2. The plant maintains good training, certification, and employee awareness of operating procedu res. 3. An electronic control monitoring system is in place for monitoring the entire engine room process. 5.0 Five-year Accident History The review of this facility's accident history includes the following range of dates: June 7, 1994 - June 7, 1999. There have been no releases at this facility as defined in 40 CFR Part 68.42(a). 6.0 Emergency Response Program As mentioned earlier, this facility has developed an emergency response in which plant employees are divided into various management and response teams. There are many in-plant contacts for an emergency which can be found in the Emergency Response Plan. There are also back-up personnel in the event that the primary incident response personnel cannot be contacted. The emergency response plan includes information about the frequency of employee emergency response training, as well as a detailed description of the training content which includes CPR and first aid training. There are also specific procedures to follow in the event of a fire and ammonia emergency. At the discretion of the Incident Commander, the Bentonville Fire Department will be called to provide emergency responders and equipment. In the event of an ammonia release, a trained on site responder will accompany the fire department into the facility. The fire department will take the lead in responding to the emergency. The Bentonville Fire Department will also be called for all fire related emergencies. In all cases where the fire department is called, an ambulance will also be called to the scene. 7.0 Planned Changes to Improve Safety Based on the PHA completed for ammonia, a list of action items was developed and is being monitored to determine if implementation was accomplished. The HAZOP method is used for each component of the ammonia system. There are numerous examples of safety improvements as a result of the PSA results. These improvements include: 1. Relocating the ammonia engine room because it was in the sam e room as the electrical switch gear. In 1995 a new room was added to the facility to facilitate this relocation. 2. A recent inspection of the chiller indicated that the ammonia piping needed replacement. The old piping was subsequently replaced. |