Matheson Tri-Gas, Inc. - Executive Summary |
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MATHESON TRI-GAS, INC. - LONGMONT, CO BRANCH RMP EXECUTIVE SUMMARY BACKROUND This Matheson Gas Products facility packages compressed specialty industrial gases in Department of Transportation (DOT), National Fire Protection Association (NFPA), and Compressed Gas Association (CGA) approved containers. This operation includes manufacturing and filling material into cylinders. The source gas for operations is manufactured at the facility and placed in cylinders. Finished product is stored and shipped in cylinders with capacities of 110 pounds to 2 pounds, depending on the size of the cylinder. The plant operates three shifts, 24-hours a day, 7 days a week. Hydrogen fluoride (HF) cylinders are processed and stored in quantities that exceed the established EPA threshold. Therefore, this process is subject to RMP regulations. HF is used as a raw material in the manufacture of another specialty gas. The HF process involves two cylinders stored together in the process area dedicated to HF operations. Each HF cylinder has a capacity of 1,330 pounds. At any given time, one cylinder will be utilized in the manufacturing process, while the second cylinder is stored until the first cylinder is emptied during manufacturing. Due to the potential quantity of HF contained in each cylinder, this process has been assigned to Program 3. DESCRIPTION OF WORST-CASE AND ALTERNATIVE CASE SCENARIOS Worst Case Scenario In compliance with the Federal definition of the worst-case scenario, a 10-minute release of the entire contents of the largest container of HF handled at the facility was modeled using RMP Comp. Such a release would involve a cylinder unit spontaneously "splitting in half" under poor weather conditions without the use of any mitigation equipment available at the facility. Due to the rigorous DOT, NFPA, and CGA codes and standards applied to compressed gas cylinder service and Matheson Tri-Gas, Inc.'s internal standards, the likelihood of this scenario occur ring is almost zero and should not be considered a credible release situation. The largest container of HF located at the facility holds 1,330 pounds of product and has a theoretical offsite impact of 1.8 miles. In accordance with EPA guidelines, the toxic endpoint was modeled without considering any mitigating equipment, such as a scrubber, process monitors, or emergency shutoff equipment, present at the facility. Alternative Case Scenario In compliance with the Federal definition of the alternative case scenario, a more realistic, yet unlikely, release scenario, having offsite impact, has been identified for HF. A release of HF from a process pipe is the identified scenario. This would occur if the piping were compromised, damaged, or defective. The likelihood of this incident occurring is decreased by operator training, preventative maintenance, and choice of pipe material of construction compatible with HF. This scenario involves a container holding 1,330 pounds of produ ct with a theoretical offsite impact of 0.1 mile. To provide the most conservative data, the toxic endpoint was modeled using a release rate calculated with the most conservative data and without considering any mitigating equipment, such as a scrubber, process monitors, or emergency shutoff equipment, present at the facility. ACCIDENT HISTORY This facility has had only one accident involving the regulated process in the last five years. There were no off-site impacts. In 1996, during equipment repair, less than one pound of liquid hydrogen fluoride was instantaneously released. There were no off-site impacts. The operator completing the repair sustained an injury from the exposure, remained at the hospital overnight for observation, and has completely recovered. In response to the incident, the facility improved gas management systems and procedures to prevent reoccurrence. . PREVENTION PROGRAM and EMERGENCY RESPONSE Compressed gas cylinders are manufactured and maintained t o the exacting codes and standards of the DOT, NFPA, and CGA. Cylinder construction is mandated in all aspects including metallurgy, wall thickness, and design pressure. The cylinder design pressure must exceed the fill pressure by a certain percentage. These codes and standards have been established to insure that compressed gas cylinders are designed to withstand extremes of operation and overpressure conditions. Each cylinder must be tested and re-qualified every 5 years. Appurtenances such as valves must meet stringent manufacturing standards as well. In addition to these codes and standards, Matheson Tri-Gas, Inc. has internal policies for handling compressed gas cylinders. Compliance with these standards, codes, and policies significantly reduces the likelihood of a catastrophic failure of a compressed gas cylinder. In addition to the integrity of the cylinder and its components, a primary element of this facility's prevention program is its experienced operators. Not on ly are they certified with the knowledge, skills, and abilities to perform their duties safely, but they are also able to assess and resolve possible abnormalities before they result in a release. Operators are present at the facility 24-hours a day, 7 days a week. An operator or supervisor cannot perform their job duties unless they have successfully completed initial training. After filling, each cylinder is leak checked. Cylinders are stored with protective caps covering the valve. The entire facility is monitored for HF gas at various key locations inside and outside the manufacturing area. The monitoring system has automatic process shutdown capabilities. The HF cylinder room is exhausted to a scrubber unit dedicated to and designed for emergency releases. This facility maintains an emergency response team that has been trained in accordance with OSHA 29 CFR 1910.120 Section Q (6)(iii). Each member receives refresher training and requalification annually. Equipment necess ary to quickly respond to an incident is kept at the facility, including monitors and an emergency scrubber. The Longmont Fire Department is invited to various walk-throughs to acquaint the staff with the facility. Contact with the City is made by phone, and the public authorities are responsible for alerting area residents and businesses. PLANNED UPGRADES The facility is currently in the process of evaluating improvements to the alarm systems, scrubber pumps, and operating and maintenance procedures. |