Ross Products Division, Casa Grande - Executive Summary |
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The Abbott Laboratories, Ross Products Division facility is located at 1250 West Maricopa Highway, in Casa Grande, Arizona. Ross manufactures infant formula and adult medical nutritional products. None of the materials used in the manufacture or packaging of these food products are considered to be regulated substances under Risk Management Program (RMP) regulations. The sole regulated chemical at the facilty is ammonia, used in a refrigeration system. All Federal requirements of OSHA's Process Safety Management (PSM) program and U.S. EPA's Risk Management Pragram are adhered to. The Ross Products facility operates a single, closed-loop ammonia system. All of the ammonia handling equipment and piping, except for the ice makers and associated piping, are located in the site's Energy Center Ammonia Room. The ammonia system is used to chill water to 33 - 40 degrees F. The frigid water is circulated throughout the plant to cool equipment and product storage tanks. At no time does the ammonia come in contact with the water. A description of the ammonia refrigerant process is included in Section 7, under the "Prevention Program Description". Since the system received its initial charge, very little ammonia has been added. Ammonia deliveries and releases are rare occurences. There have been no accidental releases of ammonia in the past five years. This may be attributed to the facility's accidental release prevention program that combines the newest equipment technologies with detailed operational procedures, preventive maintenance procedures, training and sound ammonia system management practices. In-plant emergency response procedures have been developed that incorporate both Abbott resources and emergency response services available within Casa Grande and Pinal County. The site maintains a highly trained workforce that is extremely familiar with the ammonia system and able to respond to any contigency. The site's Emergency Response Team (ERT) is available on all three shifts, and is trained to OSHA's "Hazardous Materials Technician" level. The ERT is also trained annually on the use of the Hydrocare Ammonia Spill Kit, which is used to mitigate any release that may occur. Energy Center Operators are also trained in ammonia emergency response and assist the ERT with any situation that may arise. Implementation and maintenance of systems and programs discussed in this report have the full support of Abbott management. Abbott has a global environmental, health and safety policy that applies to all Abbott locations worldwide. The policy explicitly requires all locations to: "...maintain a safe and healthy workplace and environment;" and, "...comply with all applicable laws...designed to protect human health, safety and the environment." The site's general accidental release prevention program is based on the following key elements: 1) High level of training for Energy Cent er Operators, 2) Preventive Maintenance Program, 3) State-of-the-art process and safety equipment, 4) Accurately written operating procedures, written with the participation of operators, 5) Regular hazard reviews of equipment and procedures, and 6) Ongoing auditing and Inspection program. Ammonia specific exposure prevention steps include: the availablity of self-contained breathing apparatus for operators and emergency responders; controlled access to the ammonia room; ammonia detectors; computerized process control with graphics; and a Process Safety Management program. To ensure continuing proper operation, each piece of ammonia equipment is monitored through the facility's Preventive Maintenance (PM) program. The PM's are generated automatically from a computer database at set intervals (daily to annually). Equipment is inspected and / or serviced during these scheduled PM's. Equipment condition and the work performed is documented. In addition to the PM system, each year during plant shutdown a certified ammonia contractor performs a complete inspection of each compressor. The certified contractors also check other pieces of ammonia equipment such as alarms and control systems. Included in the ammonia system's list of safety features are relief valves. Safety relief valves allow the system to vent over-pressurization in a controlled manner, avoiding a dangerous buildup of pressure. All safety valves are piped into a common relief piping system that has both a rupture disk and an ammonia detector in the piping at the discharge point. The detector is tied into the sites's monitoring system and will sound an alarm at 35ppm. All safety relief valves are replaced every five years. A "worst case scenario" using conditions predefined by U.S. EPA requires dispersion modeling to reflect all of the following assumptions: all control devices fail; the Energy Center building collapses; the entire contents of the ammonia system are realeased into the environment in ten minutes; and atmospheric conditions are selected that minimize downwind mixing. It is Abbott's strong contention that equipment design, rarely opening the system to add or remove ammonia, frequent inspection and maintenance, and high level of training provided to site personnel make actual probability of a "worst case" release an extremely remote event. The results of the "worst case scenario" would result in an off-site impact. Depending on wind direction, a long narrow plume could reach both of the following receptors: residences and industrial areas. Modeling and results are summarized in Section 2. The modeling software used was Degadis +2.1. An alternate release scenario for the Casa Grande facility involves a break in the one-inch pressurized liquid ammonia pipe which supplies an ice maker. The Icemaker is located outside of the Energy Center. The subsequent ammonia release would promptly be corrected by Energy Center personnel and mitigated by the Emergency Response Team, and would result in a much smaller off-site impact. This scenario was selected based on the fact that the icemakers are located outside and not contained by a building. The alternate release scenario results in a much smaller release that dissipates more quickly under average weather conditions. Depending upon wind speed and direction, this scenario could affect residences and industrial areas. There have been no major system changes since the implementation of the PSM program. However, there have been some minor changes which were documented by the "management of change" procedures of the PSM program. In April of 1999 another process hazard analysis (PHA) was conducted, and also an audit of the entire PSM program. The most recent recommendations are currently under review and an action plan developed. Abbott is proud of it's overall safety and environmental compl iance records. Our careful operation of the ammonia system is an integral part of safety and spill prevention planning. |