Sierra Chemical Co., Stockton - Executive Summary |
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The Accidental Release Prevention and Emergency Response Policies at the Facility: Sierra Chemical Co. relies on the Occupational Safety and Health Administration (OSHA) 29 CFR 1910.119 Process Safety Management Standard and the OSHA 29 CFR 1910.120 Hazardous Waste Operations and Emergency Response Standard to establish policies in its efforts and commitment to prevent accidental releases of highly hazardous materials through prevention and emergency reponse. Additionally, this new regulation, 40 CFR Part 68 Chemical Accident Prevention Program, Risk Management Plan, will further enhance Sierra Chemical Co. commitment to risk management. Facility and Regulated Substances Handled: Sierra Chemical Co., Stockton Facility, consists of two operations involving highly hazardous materials. The first operation is a chlorine transfer and sodium hypochlorite manufacturing (bleach) process. Chlorine is received at the facility via 90 ton railcars. There are typically two railcars and varyi ng numbers of filled smaller packagings on site for a total of 370,000 pounds. It is repackaged into 17 ton tank trucks, 1 ton containers, and 150 pound cylinders. Additionally, the facility manufactures sodium hypochlorite (bleach) utilizing chlorine as a reactant. The second operation is a sulfur dioxide container handling and storage process. Sulfur dioxide containers, 1 ton containers and 150 pound cylinders, are received at the facility and stored pending delivery to consumers. Typical inventory of sulfur dioxide is 14,400 pounds. The Worst-Case Release Scenario and the Alternate Release Scenarios: Because chlorine is received at the facility via 90 ton railcars, complying with Department of Transportation regulations, the worst-case scenario for the facility would be the release of the contents of 1 railcar. This scenario was chosen based on the requirements contained in 40 CFR Part 68. However, in contrast to the required worst-case release scenario, Sierra Chemial Co. chose the failure of a 1 inch flexible transfer line for the alternate release scenario. This scenario was chosen because with the exception of the railcar and the flexible transfer line, all other process components handling chlorine are located inside an enclosure equipped with a chlorine fume scrubber. Furthermore, through actuated valves located on both the railcar and the process side of the flexible transfer line and chlorine detectors located at the railcars interlocked with the actuated valves, it was estmated that the flow of chlorine could be stopped within 1 minute. Modelling for all scenarios was completed utilizing RMP*Comp, Version 1.06, as provided by EPA. Modelling for the worst-case release scenario demostrated potential off-site impacts to residential, schools, hospitals, county and city parks, and industrial facilities. In contrast, modelling for the alternate release scenario demostrated potential off-site impacts to adjacent industrial facilities only. For t he sulfur dioxide container storage and handling, the alternate release scenario was chosen as a leaking valve or fuse plug on a 1 ton container. While the facility has a storage enclosure equipped with a sulfur dioixde fume scrubber for the containers of sulfur dioxide, the alternate release scenario was chosen to be taking place outside this enclosure from damage substained while handling the container. The alternate release scenario assumed that trained and qualified plant personnel would mitigate the release within 60 minutes by application of an emergency repair kit. Modelling for this alternate release scenario demostrated potential off-site impacts to adjacent industrial facilities only. The General Accidental Release Prevention Program and Chemical-Specific Prevention Steps: Sierra Chemical Co. achieves accidental release prevention through the following programs. OSHA Process Safety Management Guidelines (Sierra Chemical Co. Document HS180.10), Accident Prevention Progra m (Sierra Chemical Co. Document HS105), and the Sierra Chemical Co. Workplace Audit and Compliance Audit programs. The Five-Year Accident History: Sierra Chemical Co., Stockton Facility, since beginning operation in June 1995 has had no accident, either chlorine or sulfur dioxide, that has resulted in off-site/on-site impacts as defined in 40 CFR Part 68. The Emergency Response Program: Sierra Chemical Co., Stockton Facility, has a written emergency response plan (Sierra Chemical Co. Document HS150.20) prepared pursuant to 29 CFR 1910.120(q). Applicable plant personnel receive annual training including drills. Additionally, a copy of the emergency response plan has been furnished to the Local Emergency Planning Committee. Planned Changes to Improve Safety: Sierra Chemical Co. strives to mprove safety by implementation of the OSHA Process Safety Management Standard (including compliance audits every three years and process hazards analysis revalidation every five years) and an employee safety committee. |