McLean Gas Plant - Executive Summary |
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Carrera Gas Company, L.L.C. McLean Gas Plant Risk Management Plan Executive Summary 1. Accidental Release Prevention and Emergency Response Policies Carrera Gas Company, L.L.C. is committed to employee, public and environmental safety. This commitment is demonstrated by our comprehensive accidental release prevention program that covers areas such as design, installation, operating procedures, maintenance, and employee training associated with the processes at our facility. It is our policy to implement appropriate controls to prevent possible releases of regulated substances. 2. The Stationary Source and the Regulated Substances Handled Our facility's primary activity is the operation of a Natural Gas Processing Plant for the production of Liquified Petroleum Gases. We have seven regulated substances present at our facility. These substances include Methane, Ethane, Propane, Isobutane [Propane, 2-methyl], Butane, Isopentane [Butane, 2-methyl-], and Pentane. These regulated sub stances are components of the inlet gas, the LPG product, and the residue natural gas The maximum inventory of the regulated substances at our facility is: Methane 16,000 lb Ethane 49,000 lb Propane 67,000 lb Isobutane [Propane, 2-methyl] 22,000 lb Butane 38,000 lb Isopentane [Butane, 2-methyl-] 43,000 lb Pentane 17,000 lb 3. The Worst Case Release Scenario(s) and the Alternative Release Scenario(s), including administrative controls and mitigation measures to limit the distances for each reported scenario To evaluate the worst case and alternate release scenarios, we have used EPA's Offsite Consequence Analysis Guidance Reference Tables or Equations. The following paragraphs provide details of the chosen scenarios. The worst case release scenario submitted for Program 3 flammable substances involves a catastrophic release from the Gas Plant Operations. In this scenario, 182,683 pounds of a flammable mixture containing Ethane, Propane, Isobutane, Butane, Isopentane, and Pentane is released. It is assumed that the entire contents of the full tank are released as a vapor, which finds an ignition source, with 10 percent of the released quantity participating in a vapor cloud explosion. Under worst case weather conditions, the maximum distance of 0.46 miles is obtained, which corresponds to an endpoint of 1 psi overpressure. The alternative release scenario submitted for Program 3 flammable substances involves a release from the Gas Plant Operations, which is assumed to result in a Vapor Cloud Explosion. The scenario involves the release of 182,683 pounds of flammable mixture containing Ethane, Propane, Isobutane, Butane, Isopentane, and Pentane. Under neutral weather conditions, the maximum distance to the flammable endpoint of 1 psi overpressure is 0.31 miles. 4. The General Accidental Release Prevention Program and the Chemical-Specific Prevention Steps Our facility has taken all the necessary steps to comply with the acci dental release prevention requirements set out in EPA's RMP (Risk Management Plan) regulations (40 CFR part 68). The McLean Gas Plant is also subject to OSHA's PSM (Process Safety Management) regulations (29 CFR 1910.119). The following sections briefly describe the elements of the release prevention program that is in place at our stationary source. Process Safety Information The McLean Gas Plant maintains a detailed record of safety information that describes the chemical hazards, operating parameters and equipment designs associated with all processes. Process Hazard Analysis Our facility conducts comprehensive studies to ensure that hazards associated with our processes are identified and controlled efficiently. The methodology used to carry out these analyses is the "HAZOP" method. The studies are undertaken by a team of qualified personnel with expertise in engineering and process operations and are revalidated at least once every five years. Any findings related to the ha zard analysis are addressed in a timely manner. The most recent PHA Update was performed on August 26, 1996. Operating Procedures For the purposes of safely conducting activities within our covered processes, the McLean Gas Plant maintains written operating procedures. These procedures address various modes of operation, such as initial startup, normal operations, temporary operations, emergency shutdown, emergency operations, normal shutdown, and startup after a turnaround. The information is regularly reviewed and is readily accessible to operators involved in the processes. Training The McLean Gas Plant has a training program in place to ensure that employees who are operating processes are competent in the operating procedures associated with these processes. Refresher training is provided at least once every three years, and more frequently as needed. Mechanical Integrity The McLean Gas Plant conducts documented maintenance checks on process equipment to ensure proper opera tions. The most recent review/revision of maintenance procedures was performed on August 3, 1996. Process equipment examined by these checks includes among others; pressure vessels, storage tanks, piping systems, relief and vent systems, emergency shutdown systems, controls, and pumps. Maintenance operations are carried out by qualified personnel with previous training in maintenance practices. Furthermore, these personnel are offered specialized training as needed. Any equipment deficiencies identified by the maintenance checks are corrected in a safe and timely manner. Management of Change Written procedures are in place at the McLean Gas Plant to manage changes in process chemicals, technology, equipment and procedures. The most recent review/revision of the management of change procedures was performed on July 31, 1996. Process operators, maintenance personnel, or any other employee whose job tasks are affected by a modification in process conditions, are promptly notified of the modification. They are also given any training required to safely deal with the modification. Pre-startup Reviews Pre-start up safety reviews related to new processes and to modifications in established processes are conducted as a regular practice at the McLean Gas Plant. The most recent review was performed on July 31, 1996. These reviews are conducted to confirm that construction, equipment, operating and maintenance procedures are suitable for safe startup prior to placing equipment into operation. Compliance Audits The McLean Gas Plant conducts audits on a regular basis to determine whether the provisions set out under the PSM and RMP rules are being implemented. The most recent compliance audit was conducted on July 31, 1996. These audits are carried out at least once every three years and any corrective actions required as a result of the audits are undertaken in a safe and prompt manner. Incident Investigation The McLean Gas Plant promptly investigates any incide nt that has resulted in, or could reasonably result in, a catastrophic release of a regulated substance. These investigations are undertaken to identify the situation leading to the incident, as well as any corrective actions to prevent the release from reoccurring. All reports are retained for a minimum of five years. Employee Participation The McLean Gas Plant approaches process safety management and accident prevention on a team basis. Company employees are strongly encouraged to express their views concerning accident prevention issues and to recommend improvements. In addition, our employees have access to all information created as part of the facility's implementation of the PSM and RMP rules, including information resulting from process hazard analyses. Contractors Our company hires contractors to provide specialized maintenance, construction, and other services. Prior to selecting a contractor, a thorough evaluation of safety performance of the contractor is carried out . The McLean Gas Plant has a strict policy of informing the contractors of known potential hazards related the contractor's work and the associated plant processes. Contractors are also informed of all the procedures for emergency response to an accidental release of a regulated substance. 5. Five-year Accident History The McLean Gas Plant has had an excellent record of preventing accidental releases. There have been no accidental release during the last five-year reporting period. 6. Emergency Response Plan The McLean Gas Plant has a written emergency response plan to deal with accidental releases of hazardous materials. The plan includes phone numbers for notification of emergency responders and the local emergency response agencies. We have also coordinated emergency response actions with the McLean Fire Department. This Plan is periodically updated to reflect any pertinent changes that have taken place. 7. Planned Changes to Improve Safety The developments and findings tha t result from the implementation of the various elements of our accidental release prevention program are routinely evaluated to determine whether any changes could be made to improve safety at our facility. All of the significant changes that have been identified, to date, have been implemented. |