Meadow Gold Dairies-Tulsa - Executive Summary

| Accident History | Chemicals | Emergency Response | Registration | Source | Executive Summary |

A.  Describe accidental release prevention and emergency response policies. 
 
Meadow Gold Dairies recognizes management's responsibility in protecting its employees, equipment, property, and the environment.  The safety and health of all personnel and the protection of the environment are very important.  The control of accidents has been and will continue to be a basic responsibility of all personnel in the facility. 
 
The Company has a Plant Safety Program.  The primary objective of the Plant Safety Program is to achieve maximum efficiency and saftey performance. 
 
To accomplish the Company's goal in preventing the accidental releases of ammonia and minimizing the impact of any release, the facility has developed and implemented a Process Safety Management and Risk Management program to comply with OSHAs Process Safety Management (PSM) standard (Process Safety Management of Highly Hazardous Chemicals, 29 CFR 1910.119) and EPAs Risk Management Program (RMP) regulation (Risk Management Pr 
ograms for Chemical Accidental Release Prevention, 40 CFR Part 68).  Emergency Response programs have been reviewed as well.  The objectives of the PSM/RMP programs are to prevent accidental releases through use of good operating procedures and mechanical intregrity of the ammonia refrigeration system.  The Plant Manager is responsible for the management of the accidental release prevention and emergency response programs. 
 
B.  Stationary Source and Regulated Substances Handled 
 
Meadow Gold Dairies operates a milk processing facility where milk products, juice, juice drinks and cottage cheese are processed, packaged, sold and distributed from this facility.  An important part of the processing and handling involves an ammonia refrigeration system to provide cooling during processing and storage at the facility.  The maximum intended inventory of anhydrous ammonia (CAS # 7662-41-7) contained in the system is more than 16,275 pounds. 
 
The ammonia refrigeration system is a closed loop sys 
tem whereby liquid ammonia from the high pressure receiver located outside the building is piped in special piping to refrigeration equipment used for cooling.  During cooling, the pressure of the ammonia is reduced so that the ammonia can take away heat from the milk being cooled or the cold storage rooms being cooled.  The ammonia returns in vapor form at a low pressure to the ammonia compressors where the vapors are compressed and piped to the condensers (located on the roof).  Forced air and recirculated water cool and condense the vapors in the lines.  From the condensers, the ammonia flows by gravity back to the high pressure receiver, thus completing the loop.  Ammonia is a non-corrosive chemical; therefore, does not deteriorate the inside of vessels, lines or valves.  It also carries a small amount of oil from the compresssors.  All vessels containing ammonia are ASME pressure rated above the maximum operating pressure. 
 
C.  Summary of Worst-Case and Alternative Release Scenari 
os 
 
The Worst-case release scenario at the facility involves the release of 6,999 pounds of ammonia over a 10 minute period which would result due to a failure of the high pressure receiver.  This quantity includes all the ammonia in the high pressure receiver coupled with the quantity in both ammonia condensers and the lines returning liquid ammonia to the high pressure receiver.  Under worst-case weather conditions, ammonia could travel 1.0 mile before dispersing enough to no longer pose a hazard to the public. 
 
The worst-case release scenario is highly unlikely for the following reasons: 
 
a.  The worst-case weather conditions which were used for this scenario are uncommon; 
b.  Industry and ASME standards were followed for the manufacture and quality control of the  high pressure ammonia receiver.  U-1A manufacturer's data reports were reviewed and are on file at our facility; 
c.  The high pressure ammonia receiver, while located outdoors, is protected from impact by vehicles or fork 
lifts, kept painted and routinely inspected to prevent external corrosion; 
d.  Ammonia is not corrosive in this service and our high pressure ammonia receiver is relatively new, being purchased new in 1992; 
e.  Dual safety relief valves limit operating pressure in the high pressure ammonia receiver; 
f.  The facility has a training program designed to ensure that the system is operated by experienced and qualified personnel; and, 
 
The alternative (more likely) release scenario at the facility involves the release of 240 pounds of ammonia over a 60 minute period due to a 1/4 inch break or hole in a line involving ammonia vapor at a pressure of approximately 50 psig.  These pressure conditions occur in evaporators used for keeping the cooler rooms cold or after expansion valves where ammonia is used for cooling milk.  Under alternative release weather conditions, the ammonia would be dispersed enough in less than 0.1 mile to no longer pose a hazard to the public. 
 
The likelihood of an alt 
ernative release scenario is minimized for the following reasons: 
 
a.  Positive effects of the PSM/RMP programs on the overall condition of the refrigeration equipment and operating procedures. 
b.  Most piping and valves were recently replaced.  At that time, a recirculator system, liquid trap, and ammonia transfer systems were added for safety measures to trap and return liquid ammonia to the high pressure receiver and prevent it from entering compressors and causing damage or releases.  The refrigeratin equipment and controls are in good condition. 
 
D.  Description of the Accidental Release Prevention Program 
 
The program consists of the following elements: 
 
a.  Employee Participation:  All maintenance employees participated in developing the Process Hazard Analysis (PHAs), Standard Operating Procedures (SOPs), and other elememts of the program. 
b.  Process Safety Information:  Piping and Instrumentation diagrams (P&IDs) have been developed where all ammonia vessels, lines and valves 
are numbered on the drawings.  All ammonia valves (except small guage valves) are numbered using a yellow tag with the valve number written in black on the tag.  Information has been collected which enables the employees to identify and understand the potential hazards in the system.  The written information includes the ammonia MSDS. 
c:  Process Hazard Analysis:  Formal studies with maintenance personnel participating were conducted using the What-if/Check list Technique to look at the system and indentify potential hazards.  The PHAs are maintained on a Dyadem's computer program for easy and accurate management. 
d.  Operating Procedures:  Written procedures have been developed which describe the steps which should be followed to safely operate the ammonia refrigeration system.  Although the system is controlled by an Allen Bradley PLC, the system can be run manually if necessary. 
e.  Training:  A training program has been developed which ensures that employees are trained on all asp 
ects of the system and the duties which they should perform to ensure the safe operation of the ammonia refrigeration system. 
f.  Contractors:  Contractors are screened and evaluated before they perform work on or near the ammonia refrigeration system. 
g.  Pre-Startup Safety Review:  A pre-startup safety review will be completed for all new ammonia projects involving a change to the system to verify that all safety programs are in place, training has been performed, operating procedures developed, P&IDs developed, PHA completed, and construction has been completed according to the design specifications. 
h.  Mechanical Integrity:  Annual inspections of the ammonia refrigeration system including lines and valves by a team of management and hourly personnel.  Any recommendation are resolved promptly. 
i.  Hot Work Permits:  Procedures to be followed to ensure that a signed permit is obtained prior to any cutting, welding, or burning in any area other than one designated as hot work. 
j.  Ma 
nagement of Change:  The procedures are designed to ensure that all changes made to the ammonia refrigeration system are properly reviewed. 
k.  Incident Investigation:  All incidents or near misses will be investigated, reviewed, and documented using an investigation team. 
l.  Compliance Audits:  Audits will be conducted every three years to ascertain whether or not the program is in place and working properly. 
 
E.  Five-Year Accident History 
 
No ammonia-related incidents were identified for the facility in the previous five years which resulted in significant on-site or off-site consequences. 
 
F.  Description of the Emergency Action Plan 
 
An emergency action plan has been implemented at the facility.  This program contains procedures describing how the facility will respond to ammonia spills and other emergencies, including evacuation procedures.  The program has been coordinated with the Tusla Fire Department. 
 
The emergency action program consists of the following elements: 
 
a.  Org 
anization Plan and Responsibilities 
b.  Communication Procedures 
c.  Detailed Action Plans 
d.  First Aid Procedures 
e.  Emergency Medical Treatment Procedures 
f.  Evacuation Plans 
g.  Description of Outside Assistance Available 
h.  Site Re-Entry Procedures 
i.  Training Programs and Drills 
 
G.  Planned Changes to Improve Safety 
 
A few changes to reduce the liklihood of a release were recommended during an inspection and process hazard analysis of the system.  Most involved branches off ammonia lines where valves were added for future lines or expansion, but the outlet of the valve was either not plugged or a short line extension was not capped.  These recommended changes have been evaluated will be corrected prior to June 21, 1999.
Click to return to beginning