Welch's - Executive Summary |
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Accident Release Prevention and Emergency Response Policies Welch's Risk Management Planning policy provides a comprehensive approach to prevent accidental releases of chemicals through the integration of engineering controls, administrative controls and administrative procedures. All applicable procedures from the U.S. Environmental Protection Agency (EPA) Prevention Program are adhered to. The Welch emergency response program involves the preparation of response plans detailed specifically to the Welch facility located in North East, Pennsylvania and to the emergency response services available in the community as detailed in the Welch Off-Site plan submitted and approved by the Erie County Local Emergency Planning Commission (LEPC), and is in compliance with the EPA Emergency Response Program requirements. Stationary Source and Regulated Substance Handled The Welch facility, located at South Lake Street, North East, Pennsylvania is a manufacturing facility that receives grapes and packages juices, jams and jellies. Anhydrous ammonia is used as a refrigerant. The anhydrous ammonia system includes bulk tanks, process piping, various safety and monitoring systems and various chillers. This system is manned by an operator on one shift and on other shifts, trained maintenance mechanics. Maintenance employees are on staff to respond to any alarms and to maintain the system. The offsite consequence analysis includes consideration of two release scenarios for this chemical, the "worst case scenario" and an "alternate case scenario". The worst case scenario is defined by EPA and states that "the owner or operator shall assume that the maximum quantity in the largest vessel is released as a gas over 10 minutes, " due to an unspecified failure. The alternate case scenario is defined as "more likely to occur than the worst case release scenario". Worst and Alternate Case Scenarios Atmospheric dispersion modeling has been performed to determine the potenti al distance traveled by the anhydrous ammonia before its concentration decreases to the "toxic endpoint" specified in 40 CFR part 68 Appendix A, which is 0.14 mg/L of air (200 ppm). The residential population within a circle with a radius corresponding to the toxic endpoint distance has to be defined; "to estimate the population potentially affected". The worst case scenario involves a failure of the bulk ammonia tank, containing 13,000 lbs. of ammonia, released as a gas over a ten-minute period. EPA mandated meteorological conditions, namely Stability F, wind speed of 1.5 meters per second, highest daily temperature of 98 degrees F. (as supplied from 1995-1997 PADEP Erie COPAM Station data), and average humidity of 68% (three year average of 1996-1998 as supplied by the PADEP Erie COPAM Station) were used for the worst case scenario. The facility is located in a rural area; the worst case scenario would encompass population and environmental receptors. The alternate case scenar io involves a breech (20% rupture) in the 3-inch liquid ammonia feed line to the process. A conservative duration time factor of 74 minutes was used to account for the time it would take for the contents of the vessel feeding this line to be released. Meteorological conditions used for the alternate case scenario were ambient wind speed of 3 m/s, temperature of 98 degrees F, atmospheric stability class D and relative humidity of 68%. The alternate case would also affect offsite population and environmental receptors. General Accidental Release Prevention Program and Prevention Steps The general accidental release program for anhydrous ammonia is as follows: 7 Safety training for employees who maintain and inspect the system. 7 Effective, detailed procedures for maintenance, operation and troubleshooting of the systems. 7 Preventative maintenance programs to maintain a good mechanical integrity of the system. 7 The Management of Change program identifies potential concerns before s ystem changes are implemented. 7 Detailed inspection program to identify potential concerns before they become a problem. The inspection program includes low level leak detection activities. 7 A compliance audit program that meets the criteria of OSHA's PSM standard (29 CFR 1910.119). 7 Chemical specific prevention steps for anhydrous ammonia include Level A, Level B and Level C personal protection equipment to be used for emergency response and certain other activities; training of emergency responders and maintenance employees on the toxic and physical properties of ammonia; the chemical sensing system and other safety systems; and the training of daily monitoring employees to the OSHA First Responder (8-hour) level. Five Year Accident History There have been two accidental releases of anhydrous ammonia within the past five years. In April 1997 a release occurred while repairs were being made to a cooling unit. A pipe broke from the force of a valve being closed. It was later determined that substandard pipe, not visible by inspection, had been used some 30 years earlier. There were 2 employees and 1 contractor injured in the release. Offsite responders were notified and responded. There were no offsite consequences. As a result of the accident, procedures were upgraded; all piping installed during that time period was inspected and replaced as necessary. The other accident occurred in July 1997. Packing on a valve was found to be leaking and was in the process of being repaired. Draining of the piping had begun, and ammonia from the leaking packing and the draining operation was carried by the wind into an area where an employee was working. The employee became ill and was taken for medical treatment. A total of 20 lbs. of ammonia was released. There were no offsite consequences. As a result of the incident, SOP's were upgraded, inspection frequency was increased and alternate types of valves are being investigated. Emergency Response Program Welch has a comprehensive emergency response plan, including an Offsite plan that has been approved by the Erie County Local Emergency Planning Commission (LEPC). Welch has emergency responders trained at the 24-hour technician level (OSHA HAZWOPER standard), as well as the Incident Commander level. These responders are trained to handle potential releases of anhydrous ammonia. Specific on-site response plans for handling releases of anhydrous ammonia exist. The emergency response team is well equipped with chemical sensing equipment, personal protective equipment, offensive and defensive strategy tools and equipment, radio communication, pre-determined response check lists for Incidental Command, first aid responders, EMT's and medical supplies. All Welch emergency response teams (fire, chemical and other emergency situations) use the Incident Command System. This system includes provisions for interaction and support of offsite professional emergency responders. A Process Haza rd Analysis (PHA) meeting the criteria of OSHA's PSM standard 29 CFR 1910.119 was conducted for the anhydrous ammonia system. The HAZOP (Hazard and Operability) method was used to analyze the anhydrous ammonia system. A team consisting of safety and environmental professionals, area supervisor, process engineer, analyzed the ammonia system. In regards to the mechanical integrity portion of PSM, the standard ANSI K-61.l was used to evaluate the safety and integrity of the system. The PHA was then reviewed with all operators and mechanics trained to handle ammonia at the facility to inform them of the process, the results and as a training tool. Planned Changes to Improve Safety Numerous procedures were created and many engineering improvements have been made to improve the safety and reliability of the system. A brief list of some of the changes made is listed below. 7 Control system and SOP changes to prevent overpressurization of vessel jackets during cleaning operation. 7 Addi tional guarding of ammonia piping in lift truck areas. 7 Joint efforts with area industries to share resources and enhance response to an incident. 7 Installation of additional E-stops to shut equipment down remotely. 7 Upgrades to centralized alarm system. 7 Use of a third party, independent consultant to conduct a PSM compliance audit. 7 Improvements to numerous policies and procedures, such as Hazard Communication, Hot Work Permits and Line Breaking Permits. 7 Specific emergency response training for ammonia response, conducted by P.M. HAZMAT, was provided to all mechanics and managers directly responsible for the operation of the ammonia systems of the plant. This training culminated with a live release of ammonia and the instructors as well as the training officer for the Fire Training Academy in Lake Charles Louisiana critiqued the response. Incident Commander training was also provided to all individuals in attendance. We are working with other users of ammonia in the communi ty to form a community response team that will provide back up support for each other. In addition to these changes the facility is reviewing the need for ammonia sensors, upgraded level monitoring capability. These efforts are intended to minimize the risks of a release for potential release scenarios, which were identified as having a higher potential probability. |