City of Woodville-WWTP - Executive Summary |
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1.0 RELEASE PREVENTION AND EMERGENCY REPONSE POLICIES The City of Woodville utilizes liquified chlorine gas in offering municipal wastewater treatment services to its customers. This highly regulated municipal activity includes strict adherence to the following requirements: a. The use of equipment and components designed and installed for chlorine gas service. b. Training and certification by a state agency of operating personnel in the operation of a wastewater treatment plant (WWTP). c. The coordination of City of Woodville personnel with local emergency response personnel in the event of an accidental release of chlorine from the WWTP. 2.0 STATIONARY SOURCE AND REGULATED SUBSTANCES The chlorine is stored at the WWTP on a covered concrete pad in pressurized 150-pound cylinders and 1-ton containers. The City of Woodville currently uses a pressurized system to deliver the chlorine from the 1-ton containers to the water injection system. However, Woodville is in the proc ess of installing a vacuum-regulated system. The 150-pound cylinders are stored at the WWTP pending use in water treatment service at remote well locations that are not subject to the RMP Rule. 3.0 WORST CASE/ALTERNATIVE CASE SCENARIO ANALYSES INCLUDING ADMINISTRATIVE CONTROLS AND MITIGATION MEASURES TO LIMIT THE DISTANCES FOR EACH REPORTED SCENARIO. The worst-case release scenario involves the failure of one 1-ton container, resulting in the release of 2,000 pounds of chlorine gas. The distance to the toxic endpoint is 2.2 miles. The alternative release scenario involves the release of 2,000 pounds of chlorine gas resulting from the failure of a section of flexible tubing. The distance to the endpoint is 0.6 miles. The City of Woodville limits its inventory of chlorine at the WWTP to two 1-ton containers and eight 150-pound cylinders. Only one 1-ton container is allowed to be in service at a time, thereby limiting the quantity of chlorine available for release under the alter native release scenario. 4.0 PREVENTION PROGRAM AND CHEMICAL SPECIFIC PREVENTION STEPS The City of Woodville WWTP was designed, installed, and is operated in accordance with applicable codes, standards, and guidelines which include: a. The use of 150-pound cylinders and 1-ton containers authorized by the Department of Transportation (DOT) for liquified chlorine gas service. b. The use of cylinder and container shut-off valves and pressure relief devices meeting the requirements of the Chlorine Institute (CI) for liquified chlorine gas service. c. The inspection, testing, repair, or replacement of the 150-pound cylinders, 1-ton containers, valves, and relief devices in accordance with DOT and CI requirements. d. The use of a tubing, piping, and valves designed for pressurized chlorine gas service and configured to prevent water intrusion, which would compromise system integrity. The City of Woodville uses operating procedures developed to ensure that the 150-pound cylinde rs and 1-ton containers are not dropped, improperly installed, or otherwise damaged, during the unloading and loading, handling, storage, and use at the WWTP. These procedures are reviewed and revised as needed to reflect the system configuration, as well as to incorporate improvements or changes in industry and safety codes and standards. Trained personnel are used in the maintenance of the chlorine system components such as the flexible tubing, header piping, and pressure-reducing regulators. Maintenance procedures are reviewed and revised as needed to comply with industry and safety codes and standards. The City of Woodville conducts periodic hazard reviews and compliance audits in accordance with the RMP Rule. 5.0 FIVE YEAR ACCIDENT HISTORY In the past five years, there have been no accidental releases of chlorine that resulted in deaths, injuries, or significant property damage onsite, or know offsite deaths, injuries, property damage, environmental damage, evacuations, or sheltering in place. 6.0 EMERGENCY RESPONSE PROGRAM The City of Woodville WWTP is included in the community emergency response plan developed under 42 U.S.C. 11003. Appropriate mechanisms are in place to notify emergency responders when there is a need for response. 7.0 PLANNED CHANGES TO IMPROVE SAFETY The vacuum-regulated chlorine delivery system will be installed at the City of Woodville WWTP to replace the current pressurized system. This change will significantly improve the safety of the WWTP by eliminating all pressurized tubing and piping in the chlorine gas delivery system. |