Fairway Foods - Executive Summary
EXECUTIVE SUMMARY |
Accident Release Prevention Program and Emergency Response Policy
It is the policy of the Fairway Foods, Inc. (Fairway Foods) Northfield, Minnesota, facility management to implement the requirements of this Risk Management Program (RMP) in accordance with the USEPA regulations under 40 CFR Part 68 and with the corresponding regulations under OSHA's Process Safety Management (PSM) program. The objective is to minimize the risk of a release of a hazardous material and if a release occurs, to minimize the potential impact to Fairway Foods employees, the public and the environment. This objective will be accomplished by utilizing general good operating procedures, providing appropriate training to all employees, and coordinating response activities, as necessary, with the local emergency response providers. This plan covers all Fairway Foods owned activities at this facility.
Fairway Foods management is committed to providing the resources necessary to implement this p
Fairway Foods operates a distribution warehouse of food and convenience goods. Support operations include a truck repair facility, cold storage, and administrative offices. Figure 1-1 shows the location of the facility.
One chemical is utilized at the facility in sufficient quantities to be subject to the requirements of 40 CFR Part 68. This chemical is ammonia and is used as a refrigerant throughout the facility.
Worst-Case and Alternative Release Scenarios
RMP regulations require that each facility identify worst-case and alternative case release scenarios. EPA has defined a worst-case release as the release of the entire contents of the largest vessel that contains a regulated substance in a 10-minute period. This release rate is then evaluated using modeling techniques and/or reference tables to define the distance to a specified endpoint (concentration or overpressure). The distance to the endpoint is affected by several factors including molecula
r weight, volatility, heat of combustion, and physical setting (urban or rural).
The alternative release scenario must be one that is more likely to occur than the worst-case scenario and that reaches an endpoint off site, unless no such scenario exists. The alternative release scenario is also evaluated to define the distance to the specified endpoint.
Under 40 CFR 68 Subpart B '68.22(e), the RMP rule identifies surface roughness as a parameter to be used in the hazard assessment to determine the physical setting of the site, urban or rural. "Urban means there are many obstacles in the immediate area; obstacles include buildings or trees. Rural means there are no buildings in the immediate area and the terrain is generally flat and unobstructed."
Due to the presence of trees, hills, and/or other structures in the immediate vicinity of the Northfield, Minnesota, facility, an urban dispersion environment was assumed.
The data provided in the document "Model Risk Management Pr
ogram and Plan for Ammonia Refrigeration" (May 1996) was used to estimate the toxic endpoint distance for the worst-case and alternative ammonia release scenarios. The EPA's "RMP Off-site Consequence Analysis Guidance" (May 1996) was not used to determine the toxic endpoint since it classifies ammonia as a neutrally buoyant gas. Since the worst-case ammonia release would involve liquid and would come from a pressurized system containing liquid, the released gas should be classified as a dense gas (a result of evaporative cooling). The ammonia refrigeration document provides calculated endpoint distances for typical meteorological conditions.
The worst-case release scenario for an anhydrous ammonia release included a release of all the contents of the intercooler # 2 vessel in a 10-minute period (per EPA guidelines). The intercooler #2 vessel has the largest capacity in the facility. This scenario translates to a release of 24,902 pounds of ammonia in 10 minutes or 2,490 lbs/min.
Assumptions included in the worst-case assessment are: the ammonia is a liquefied gas; intercooler # 2 vessel is not diked; the release does not take place indoors; the nearfield dispersion environment is characterized as urban; 10-minute averaging period; the wind speed is 1.5 meters/sec and the atmospheric stability is classified as F (stable). Additionally, 24,902 pounds is the largest quantity of ammonia capable of being stored in the vessel.
The results of the worst-case assessment for ammonia show that the plume must travel 1.80 miles (2.89 kilometers) before dispersing to the endpoint concentration of 201 ppm. Figure 1-2 shows the endpoint radius for the worst-case release scenario.
The selected alternative release scenario for the ammonia system is a release from a relief valve due to overpressure of a compressor unit. The largest relief valve in the system was used in this scenario. The largest relief valve has a relief rate of 69.1 pounds of air per minute. As a matter of
convention, the specified release rate of any relief valve is always in pounds of air per minute. The release rate of 69.1 pounds of air per minute correlates to a release rate of 49.0 pounds of ammonia vapor per minute. This release rate was applied to a release from the ammonia header on top of the building.
The ammonia refrigeration document provides calculated endpoint distances for typical meteorological conditions (3 m/s wind speed, D atmospheric stability, 50% relative humidity). It has been determined, through a review of Fairway Foods operational history, that the total release would likely be 500 pounds of ammonia. Based on the ammonia release rate of 49.0 lbs/min, the duration for a 500-pound release is 10 minutes. Other assumptions include that no active or passive mitigation measures are currently in place and an urban dispersion environment in the nearfield. The results of the alternative release scenario for an ammonia release indicates that the endpoint concentra
tion of 201 ppm is reached at 0.064 miles (103 meters) from the release point. The endpoint radius for the alternate release scenario is limited to the Fairway Foods property.
General Accidental Release Prevention Program and Chemical Specific Prevention Steps
The Northfield, Minnesota, facility is governed by a set of OSHA and USEPA regulations that require planning and facility activities intended to prevent a release of hazardous material, or if a release inadvertently occurs, to minimize the consequences of a release to the employees of the facility, the public and to the environment. These regulations include:
* 40 CFR Part 68, Accidental Release Prevention
* 40 CFR Part 112, Spill Prevention, Control and Countermeasure
* 40 CFR Part 264, Hazardous Waste Contingency Plan
* 29 CFR Part 119, Process Safety Management
* 40 CFR Part 302, Emergency Planning and Community Right-to-Know Act (EPCRA)
The key concepts in Fairway Foods release prevention program are employee participation,
appropriate design and maintenance of equipment, and appropriate training of all employees. Fairway Foods has developed and documented these elements in their PSM plan. The PSM plan is incorporated with this document by reference.
Employee participation in the release prevention program is encouraged and supported by Fairway Foods management. Key personnel are responsible for conducting and implementing the findings from the Process Hazard Analysis (PHA) for the ammonia systems. Fairway Foods employees are also members of the facility emergency response team.
Fairway Foods policy is to construct all new equipment, systems, and facilities to ensure the appropriate safety and release prevention systems are included from the beginning of each project. Additionally, Fairway Foods has recently initiated a program of maintenance activities to ensure that key systems are maintained appropriately to minimize the risk of a release.
Fairway Foods is committed to providing appropriate traini
ng to all employees regarding safety procedures. Each new employee is provided comprehensive safety training during their initial orientation for the facility. Additional training is provided to maintenance personnel for the systems they are responsible for. Members of Fairway Foods emergency response team receive annual training to ensure that response actions are promptly and safely completed.
Five Year Accident History
A qualified release of ammonia is defined as an accidental release resulting in deaths, injuries, or significant property damage on-site, or known off-site deaths, injuries, evacuations, sheltering in place, property damage, or environmental damage.
Fairway Foods has not had a qualified release of ammonia from the Northfield, Minnesota, facility within the last five years.
Emergency Response Program
Fairway Foods has personnel trained in emergency response available to the facility seven days per week. These personnel receive annual training on emergency procedure
s and response techniques.
Planned Changes to Improve Safety
Fairway Foods completes a thorough review of the ammonia systems each time a design change is implemented. Fairway Foods is committed to using these methods to identify and implement ways to improve the safety of these systems.