NUNES COOLING INC. - Executive Summary
NUNES COOLING INC. is located within the city limits of Salinas, California, in a predominately business/industrial area, and is a produce pre-cooling, cold storage, and shipping facility. The facility was first constructed on this site in the late 1960's and has been in continuous seasonal operation since that time. Anhydrous ammonia is used as the closed loop system refrigerant for the pre-cooling and cold storage equipment and is the only acutely hazardous chemical used on the site . The facility consists of approximately 40,000 sq ft of cold storage warehouse space and various types of fixed and mobile pre-cooling equipment on the aproximate 12 acre site. |
The risks to the community from this facility would come from an incident in which the ammonia normally contained within the refrigeration system was allowed to escape into the atmosphere. In the worst-case scenario the toxic end point is located off the property within the community, the alternate release s
cenario was selected as the most likely event that would have a toxic endpoiont located off of the subject property. Events which were considered possible and able to cause a release of ammonia for the purposes of the Hazard Evaluation were: equipment failure, operator error, design deficiency, vehicular accident, acts of sabotage/vandalism, fire and earthquake. It is expected that other specific events would have similar results as those listed above. Direct contact with the released ammonia vapor by people inside the toxic endpoint is the main area of concern.
The worst case release scenario considered was as required, specifically being the release of 100% of the ammonia contained within the largest vessel over a 10 minute period. The analytical results of this scenario show a distance to the toxic endpoint of approximately .9 miles, which includes mainly industrial development with a smaller amount of residential area. The alternative release scenario chosen as t
he most likely event involves the release of 300 lbs. of ammonia over a 30 minute period from a leaking valve or cracked pipe. The distance to the toxic endpoint would be approximately .1 miles in this case. Both scenarios result in off-site impacts.
Mitigation of ammonia releases is addressed by the following:
1. System design and construction
2. Administrative controls
3. Containment curb inside the main engine room
4. Diffusion tanks for PRV releases
5. Operating engineer on-site daily
6. Off-hours security service
7. A release inside of a building would require closing the building doors
Administrative controls and policies to be used in the event of a release are contained in the existing
" Business Response Plan - 1999". The major topics covered by this document are:
1. Emergency Contact List
3. Notification Procedures
4. Hazardous Material Inventory
5. Site Plan, Facility Layout
6. Personnel Responsibilities
7. Evacuation Plan and Procedures
8. Employee Training
9. Employer Emergency Response Checklist
Risk reduction steps have been and are continuing to be implemented Nunes Cooling Inc. to .minimize the possibility of an accidental release of ammonia, and in the event of an accidental release, to minimize the effects upon the community. The essential risk reduction steps now in effect at this facility are:
1. Regular daily equipment inspections
2. The daily recording of equipment operating data
3. Maintaining equipment maintenance records
4. Maintaining records of previous releases and their causes
5. Proper training of operators
Mechanical and electrical system controls automatically maintain the correct system
temperatures and pressures, and provide safety shut-down and pressure relief in
the event that the system operates out of the design limits.
7. Ammonia diffusion tanks are installed to contain ammonia that could be released through
a pressure relief valve in the main engine room.
8. Pressure vessels are equiped with high level alarm switches.
9. All equipment and system components are designed for ammonia service
10. The system was designed and installed in accordance with applicable Federal, State
and local codes and ordinances.
11. This facility currently operates under an Community Emergency Response Plan which:
a. Identifies the Emergency Coordinator and Emergency Contacts
. Details the Emergency Notification Procedures
c. Contains procedures for hazardous material incidents
d. Details reporting procedures
e. Contains the evacuation plan
f. Shows the locations of all acutely hazardous materials on-site
g. Shows the locations of emergency response and mitigation equipment on-site
This facility has experienced one ammonia release within the last five years which resulted in the evacuation and/or sheltering in place of neighboring properties for approximately two hours. No injuries, property or environmental damage occured. The release occured during on-site construction of refrigeration system modifications when an isolation valve began leaking into an unfinished pipeline extension.
Recommended plant improvements to increase safety as a result of the incident:
1. Provide pipe labeling as per UMC a
nd ANSI/ASHRAE standards for the cold storage facility.
2. Label main valves on new compressor package on portable equipment.
3. Label piping on evaporative condenser on portable equipment.
4. Ammonia leak detection system to be installed.
5. Adopt notification procedure to be used prior to starting work on the system.
6. Adopt specific maintenance and construction procedures.