Valley Sweet - Executive Summary
Risk & Process Safety Management Program Executive Summary |
13125 Road 248
Tulare, California 93274
FAX (559) 686-9246
EPA Facility ID#: Applied For
December 8, 1999
Solutions Environmental Health & Safety, Inc.
6687 N. Blackstone Avenue, Suite 103
Fresno, California 93710
Table of Contents for Preface - Executive Summary
1. THE VALLEY SWEET RISK & PROCESS SAFETY MANAGEMENT PROGRAM 1
2. DESCRIPTION OF AMMONIA SYSTEM 1
3. AMMONIA RELEASE SCENARIOS 2
3.1 WORST CASE SCENARIO 2
3.2 ALTERNATIVE CASE SCENARIO 2
4. GENERAL ACCIDENT RELEASE & AMMONIA SPECIFIC PREVENTION STEPS 3
5. FIVE YEAR ACCIDENT HISTORY 3
6. EMERGENCY ACTION PLAN 3
7. PLANNED CHANGES TO IMPROVE SAFETY
1. THE VALLEY SWEET, RISK & PROCESS SAFETY MANAGEMENT PROGRAM
This is to inform all interested persons, including employees, that Valley Sweet is preparing a unified Risk & Process Safety Management Program. The program will be in complia
nce with California's Accidental Release Prevention (CalARP) Program (in California CCR Title 19, Chapter 4.5 Program Level 3 Elements. At the Federal level, Title 40 CFR Part 68), and California OSHA's "Process Safety Management (PSM) of Acutely Hazardous Materials" standard (in California CCR Title 8, Section 5189, "Process Safety Management of Acutely Hazardous Materials," and Federally Title 29 Code of Federal Regulations (CFR) 1910.119). This program is being prepared to address the risks involved with the presence of anhydrous ammonia in an amount in excess of 10,000 lbs., which is contained in our refrigeration system.
Our program will promote overall plant, worker, and public safety. The program will enable our facility to prevent the occurrence, and minimize the consequences, of significant releases of anhydrous ammonia. Overall, the program is designed to prevent accidental fatalities, injuries and illnesses and avoid physical property damage.
Our company has an exemplar
y safety record, one that we are quite proud of. Our company has many policies and procedures in place to promote overall plant, worker and public safety. The Risk Management Plan unifies our efforts, and sets forth rules, procedures and practices which will help our employees protect themselves and our neighbors.
2. DESCRIPTION OF AMMONIA SYSTEM
The Valley Sweet facility is a commercial packinghouse for grapes. The facility has an ammonia system that provides refrigeration capacity to multiple cold rooms used to cool or store fruit. Five rooms are equipped with "bunker style" evaporator coils that contain chilled liquid ammonia, of which two are used for precoolingand three for storage. Ten rooms are controlled atmosphere rooms with ceiling mounted evaporator coils. There is a hydrocooler and a refrigerated central corridor as well. A computer system provides substantial control and alarm capability.
High pressure liquid from a high pressure receiver is piped to a series of
a liquid feed solenoid valves. From there, high pressure liquid is piped to each cold room, where it passes through an expansion valve into a low pressure accumulator vessel. Low temperature liquid circulates by thermal convection through the evaporator coils located behind bunker walls in the cold rooms or hung from the ceiling. Low pressure and temperature gas collects in the accumulator vessel, and passes through a pressure regulator into a suction line. The suction line returns the vapor to a main suction accumulator vessel located in the engine room, which separates any residual liquid from the gas. The gas is piped to five screw compressors which elevate the temperature and pressure of the gas. The high pressure discharge from the compressor is sent to water cooled evaporative condensers where the high pressure gas ammonia is liquified and returned to the high pressure receivers. Liquid separated from the suction return gas in the main suction accumulator vesses drains into
a liquid transfer vessel. Operation of a float switch activated solenoid valve raises the pressure in the liquid transfer vessel to the point the liquid can be drained into the high pressure receiver.
The facility was built by professional refrigeration engineers in accordance with ANSI/IIAR 2-1992 "Standard for Equipment, Design, and Installation of Ammonia Mechanical Refrigerating Systems". It was also built in compliance with the Uniform Mechanical Code and Uniform Building Code applicable at the time of construction. The system contains numerous safety devices including sensors which stop the compressors if temperatures or pressures exceed or drop below established limits, and safety relief valves which vent ammonia gas to the atmosphere if the pressure in the system exceeds their set point. An emergency "dump box" contains switches and valves to turn off equipment and vent ammonia if necessary.
There is only one ammonia system at our facility. Therefore, we are treating
our facility as a single process.
3. AMMONIA RELEASE SCENARIOS
3.1 Worst Case Scenario
At Valley Sweet, our worst case scenario is the failure of our high-pressure receiver containing 25,000 lbs. of ammonia. Following the instructions set forth in EPA's "Risk Management Program Guidance for Ammonia Refrigeration (40 CFR Part 68)," we considered the failure of one vessel. We did not include any liquid ammonia in pipework connected to the failed vessel or in any other vessel that could discharge directly into pipework connected to the failed vessel. . Under this scenario, the release would be passively mitigated by the fact that the primary receiver vessel is inside an enclosed engine room. The ammonia would be released over a ten-minute period.
Using RMP*Comp we estimate that the ammonia would travel 2.2 miles (rural conditions) before dispersing enough to no longer pose a hazard to the public.
3.2 Alternative Case Scenario
Our ammonia refrigeration system is equipped with safet
y relief valves. These valves limit the operating pressures of the entire system, and prevent failures due to over pressurization. Our alternative release scenario is as follows. A high-pressure safety relief valve lifts and fails to reseat. The rated release rate for our high-pressure safety relief valve is 70 lbs./min. We assume the leak would continue for 10 minutes until the header pipe was switched over to the backup safety relieve valve. Following industry practice, our relief valves are installed in pairs with a switch over valve, and the discharge is piped to a release point that is remote from the valve. Under this scenario 700 lbs. of ammonia would be released over a time period of 10 minutes.
Using RMP*Comp we estimate that the ammonia would travel less than 0.1 miles (rural conditions) before dispersing enough to no longer pose a hazard to the public.
4. GENERAL ACCIDENT RELEASE & AMMONIA SPECIFIC PREVENTION STEPS
The ammonia refrigeration system at the Valley Swee
t facility is an integral part of the overall business. It is extremely important that it is maintained and operated in a safe and efficient manner. Management is committed to making sure that all employees are made aware of the potential danger of an ammonia leak.
Our refrigeration personnel monitor the ammonia refrigeration system/process and keep an active journal of all procedures and transactions that pertain to ammonia. In addition, the system/process is checked frequently by our outside refrigeration contractor, the Stellar Group, who also assists us in performing preventative maintenance and reviews of our system/process equipment.
We inform our employees of the dangers of an accidental release of ammonia in a tailgate safety meeting. New employees are made aware of the potential risk of ammonia in an employee orientation meeting. During these meetings we also discuss preventative measures, such as evacuation, in order to be prepared for a release.
Our ammonia refriger
ation system was designed and built by professional refrigeration engineers in accordance with ANSI/IIAR 2-1992 "Standard for Equipment, Design, and Installation of Ammonia Mechanical Refrigerating Systems." It was also built in compliance with the Uniform Building Code and Uniform Mechanical Code applicable at the time of construction.
Our ammonia refrigeration system is equipped with safety relief valves. These valves limit the operating pressures of the entire system, and prevent failures due to overpressurization. In the event of a valve lift, ammonia would not be released to the atmosphere because the relief valves are plumbed to a common header pipe which transfers the vapor into a water diffusion tank.
5. FIVE YEAR ACCIDENT HISTORY
Valley Sweet has had one reportable accident within the last five years.
The accident occurred in the afternoon on August 15, 1997. The accident involved the release of liquified ammonia over a period of approximately 45 minutes. The ammonia
was released from an evaporator coil that had been damaged by a metal cover that had been thrown from a fan. The metal cover had not been put back in place on an electrical housing by maintenance workers who were performing preventative maintenance on fan motors. The release occurred indoors, and was entirely contained indoors. The weather at the time of the accident is not known. 911 was dialed, and the local fire department responded. Actions taken included isolating and evacuating the area, and checking to see whether any employees had been injured by breathing ammonia vapors.
As a result of the accident one employee was given two days off to recover from a sore throat caused by breathing ammonia vapors. Approximately $40,000 worth of produce was lost when it became contaminated with ammonia.
A subsequent accident investigation made it clear that the release was the result of human error. Since the time of the accident we have revised our training and maintenance procedures
to decrease the liklihood of human error, and modified our emergency response plan to ensure a more rapid and efficient response.
6. EMERGENCY ACTION PLAN
This facility's emergency response program is based on the Cal/OSHA requirements for Emergency Action Plans (in California CCR Title 8, Section 3220, "Emergency Action Plans." Federally, Title 29 CFR 1910.38 and 1910.119), HAZWOPER (standard (in California CCR Title 8, Section 5192, "Hazardous Waste Operations and Emergency Response," and Title 29 CFR 1910.120).
Strategically, we will respond defensively to a release. Under this plan our ammonia refrigeration personnel will take whatever steps are necessary to bring a release under control. The first priority will be to operate the ammonia system to bring a release under control safely, from a distance, without donning personal protective equipment. To better prepare for this type of action, initial training to the defensive level (First Responder, Operations Level) as defined
in the HAZWOPER regulations will take place within the next year. All response activities would be done in coordination with the local fire department and the Tulare Fire Department Hazardous Materials Response Team.
Every year at the beginning of the season we review with our employees our evacuation procedures in the event of an emergency, including an ammonia release.
7. PLANNED CHANGES TO IMPROVE SAFETY
As of December 8, 1999, the time that this Executive Summary is being submitted, our Risk & Process Safety Management Plan is not finished. Initially, we though we were a Program 1 facility. However, we have since come to understand that we are a Program 3 facility. To prepare a Program 3 plan we have found it necessary to obtain help from outside vendors for some critical elements, such as preparing Piping & Instrumentation Diagrams and conducting a Process Hazard Analysis. These vendors are attempting to meet the requests of numerous facilities such as ours at the same time
, and have the same problem of only a limited number of people qualified to carry out the required tasks. Thus, these vendors are setting completion dates for plan elements that we cannot entirely control. Therefore, our company is requesting an extension of 60 days to complete our revisions. Our plan will be submitted in its entirety by Monday, February 7, 2000.
We understand our obligations to consolidate our safety activities in a Risk Management Program under the CalARP regulation. We are committed to preparing and implementing a Risk & Process Safety Management Program according to this timeline.