Southland Oil Company - Vicksburg - Executive Summary |
ACCIDENTAL RELEASE PREVENTION AND RESPONSE POLICIES Southland Oil Company has a long-standing commitment to worker and public safety. This commitment is demonstrated by the resources invested in accident prevention, such as training personnel and considering safety in the design, installation, operation, and maintenance of our processes. Our policy is to implement reasonable controls to prevent foreseeable released of regulated substances. However, if a release does occur, our trained personnel will respond to control and contain the release. DESCRIPTION OF THE STATIONARY SOURCE AND REGULATED SUBSTANCES Southland's Vicksburg terminal is located along the Yazoo diversionary canal and is used primarily for the the transfer of petroleum products as well as caustic soda and sodium hydrosulfide. HAZARD ASSESSMENT RESULTS The worst-case scenario (WCS) associated with the storage of light naphtha is a vapor cloud explosion (VCE) of the storage tank with a capacity of 15,000 barrels. U sing the vapor cloud explosion methodology in RMPComp, a 1 psi ring study was calculated using gas chromatograph analysis for light naphtha. [Note: the analysis indicated i-Butane (1.152%), n-Butane (4.662%), i-Pentane (6.423%), and n-Pentane (9.291%).] With a density of 5.7 lbs per gallon. an overpressure of 1 psi was determined to extend .7 miles from the storage tank. Although we have numerous controls to prevent such releases and to manage their consequences, no credit for administrative controls or passive mitigation measures was taken into account in evaluating this scenario. The full tank inventory of regulated substances is assumed to release, completely vaporize, and ignite, resulting in a VCE. The alternative release scenario is a boiling liquid, expanding vapor explosion (BLEVE) of the pentane in the light naphtha tank. The most likely scenario would be a fire in the tank yard exterior to the light naphtha tank. Once again, using the RMPComp software, a exposure w hich would cause second-degree burns would extend .6 miles for the location of the tank. GENERAL ACCIDENT RELEASE PREVENTION PROGRAM STEPS While threshold quantities of toxic and flammable substances are not met for any of Southland's processes other than storage of light naphtha, we have developed process safety guidelines for processes that represent the greatest risk to Southland employees, the public, and the environment. In addition to these process safety guidelines, Southland has numerous other programs which incorporate accident prevent and loss control. Employee participation takes place on both an informal and formal basis. Informally, safety suggestions and concerns are relayed to management through supervisors or directly. The safety manager also collects suggestions during safety walk-throughs. Once a quarter (and often more frequently) a meeting is held with the union safety committee to discuss safety related issues. Additionally, a safety meeting is held once a quarter at an offsite location (restaurant) to cover highlighted safety topics. Process safety information is keep with several departments at the refinery including the EHS, maintenance, and analytical laboratory departments. In addition to typical hazard communication information, documents are also kept on key process parameters, chemical mixture, technical manuals for key equipment, and industry guidelines for safe operations in petroleum refineries. As the storage tank for light naphtha has few "process" controls, a checklist analysis was developed to address process hazards. The light naphtha storage tank has an internal floating roof with is the key component which could fail and significantly increase the risk of a VCE or BLEVE. The storage tank is also gauged daily. During this gauging the tank is inspected for problems or weakened components. Southland Oil Company has historically experienced a very low employee turnover rate. As a consequence, refinery personnel are quite knowledgeable and effective at on the job training. Additionally, all employees are trained under OSHA's 24 hour Hazardous Waste Operator Standard and at the state fire academy for fire brigade training. Refreshers are conducted annually for Hazwoper and semi-annually for fire training (two days). Southland Oil Company has historically used the same contractors for construction and maintenance within the facility. Contractors are expected to know and follow Southland's safety standards and to work under the oversight of a Southland supervisor at all times while within the refinery facility. While a pre-startup safety review has not been part of the light naphtha storage, a PSSR is followed within the refinery and would be part of any maintenance operation or equipment modification. For modifications, this PSSR would be part of the permit modification process (operating and Title V). Mechanical integrity of the storage tank is focused on the proper operation and maintenanc e of the internal floating roof and the gauging for thickness of the steel shell. During all maintenance operations, standard safe work practices are utilized including lockout/tagout, line breaking procedures, confined space safety, hot work permits, and static electric spark minimization. While the operational controls would not change much over time, management of change is still considered critical when changes are made to other processes and especially safety systems. Accident and incident investigation are conducted whenever there has been an accident, near miss, or other incident. Recommendations are typically resolved at the time. A compliance audit is conducted on the storage tank during its semi-annual inspections for floating roof tanks. CHEMICAL SPECIFIC PREVENTION STEPS The key element of release containment, control, and mitigation is the permanent foam chamber install in the roof of the storage tank. Adequate inventories of foam are onsite, in both 5 and 55 gal lon containers, to extinguish a fire in the tank. External monitors and other fire suppression equipment are stored near the vicinity of the tank . FIVE-YEAR ACCIDENT HISTORY Southland Oil Company has maintained an excellent accident prevention record for the last five years. In reviewing the OSHA 200 logs for 1994, 1995, 1996, 1997, and 1998 there were no accidents or incidents related to the process. EMERGENCY RESPONSE PROGRAM INFORMATION Southland Oil Company maintains written emergency response programs for a variety of regulatory programs. The programs include: TIER II reports for EPCRA, emergency action plans, emergency response plans, SPCC plans, pipeline spill response plans, and process safety management plans. PLANNED CHANGES TO IMPROVE SAFETY Southland Oil Company plans to extend the supply line for the foam chamber at the light naphtha storage tank from its current location to a more accessible location for supplying foam in the event of a fire. |