City of Commerce-SWTP - Executive Summary
1.0 RELEASE PREVENTION AND EMERGENCY REPONSE POLICIES |
The City of Commerce utilizes liquefied chlorine gas in offering municipal surface-water 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 surface water treatment plant (SWTP).
c. The coordination of City of Commerce personnel with local emergency response personnel in the event of an accidental release of chlorine from the SWTP.
2.0 STATIONARY SOURCE AND REGULATED SUBSTANCES
The chlorine is stored at the SWTP in pressurized 1-ton containers secured to an engineered storage cradle mounted onto a concrete pad. The City of Commerce utilizes a vacuum-regulated system to deliver the chlorine from the 1-ton containers to the water injection system.
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 1.3 miles. The alternative-release scenario involves the release of 2,000 pounds of chlorine gas resulting from the failure of a shut-off valve on a 1-ton container that had been placed into service. The distance to the endpoint is 0.3 miles. The City of Commerce limits its inventory of chlorine at the SWTP to three 1-ton containers. The vacuum-regulated system allows one 1-ton container to be in service and one 1-ton container to be in standby, yet limit the quantity of chlorine available for release under the alternative-release scenario to only one 1-ton container.
4.0 PREVENTION PROGRAM AND CHEMICAL SPECIFIC PREVENTION STEPS
The City of Commerce SWTP was designed, in
stalled, and is operated in accordance with applicable codes, standards, and guidelines which include:
a. The use of 1-ton containers authorized by the Department of Transportation (DOT) for liquified chlorine gas service.
b. The use of 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 1-ton containers, valves, and relief devices in accordance with DOT and CI requirements.
The vacuum-regulated system utilized at the City of Commerce SWTP is extremely safe since it is designed to eliminate the release of chlorine gas from system components downstream of the vacuum regulator, which is mounted directly onto the 1-ton container.
The City of Commerce uses operating procedures developed to ensure that the 1-ton containers are not dropped, improperly installed, or otherwise damaged, during the unloading and loading, handling, storage, a
nd use at the SWTP. 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 vacuum regulators. Maintenance procedures are reviewed and revised as needed to comply with industry and safety codes and standards.
The City of Commerce 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 known offsite deaths, injuries, property damage, environmental damage, evacuations, or sheltering-in-place.
6.0 EMERGENCY RESPONSE PROGRAM
The City of Commerce SWTP is included in the community emergency response plan developed under 42 U.S.C. 11003. Appropriate mechan
isms are in place to notify emergency responders when there is a need for response.
7.0 PLANNED CHANGES TO IMPROVE SAFETY
The City of Commerce SWTP operating and maintenance procedures will be reviewed and updated as necessary.