City of Beaumont Loeb Chlorination Facility - Executive Summary |
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Facility Description The City of Beaumont Loeb Chlorine Facility provides treated water to the City and surrounding areas. Water is disinfected with chlorine in the treatment process and then distributed to residential, commercial, and industrial users. The Facility maintains a maximum inventory of 16,000 pounds of chlorine, which is above threshold quantity established by the Environmental Protection Agency and therefore subject to the requirements of the Risk Management Program. Chlorine, a chemical required by regulation to be used in the disinfection process, has been in use at the Loeb Facility since operation began. One accidental release of chlorine meeting the requirements of the five year accident history, as defined in the Risk Management Program regulations, occurred at the facility in May 1999. Operating and maintenance procedures have been modified, and update training has been conducted as a result of the accident. No offsite impacts occurred as a result of this acci dent. Offsite Consequence Analysis The off-site consequences of potential accidental releases of chlorine at the Loeb Facility were assessed in accordance with requirements established in 40 Code of Federal Regulations, Part 68. SLAB Atmospheric Dispersion Model, an EPA-recognized computer modeling program, was used to model a worst case release scenario and an alternative release scenario. The worst case scenario is a model of a chlorine release under specific conditions established by EPA, including release volume, duration, and weather conditions. Active safety systems in place at the Loeb Facility that are designed to minimize the effects of a chlorine release cannot be considered in the worst case scenario. The worst case release scenario is required to assume the release in a ten minute period of the entire contents of the largest vessel of the regulated chemical onsite, which for the Loeb Facility is a one-ton chlorine container. Meteorological conditions required by EPA rules are assumed for the release. The toxic endpoint for the worst case release scenario is estimated to reach a point beyond the boundary of the facility. Since this facility is located in a populated area, the chlorine vapor would reach offsite endpoints and nearby public receptors. Big Thicket National Forest is the only sensitive environmental receptor located within the release area. The alternative release scenarios represent the results more likely to occur in the event of a chlorine release at the Loeb Facility. Active safety systems at the Loeb Facility are considered for the alternative release scenario. Average weather conditions at the facility are used for this release scenario, as recommended by EPA regulations. Failure of a gas pipe in the chlorine feed system is assumed for the chlorine alternative release scenario. While the toxic endpoint for the chlorine alternative release scenario is estimated to reach a point beyond the facility boundary, no sensitive e nvironmental receptors designated by EPA are affected by this release scenario. One public receptor is located within the release area. Prevention Program The Loeb Facility is subject to Prevention Program 2 of the Risk Management Program. In accordance with the requirements of Program 2, the Loeb Facility maintains specifications for the equipment associated with the chlorine feed system and has documented the codes and standards adhered to in designing, constructing, and operating the system. The safe operating ranges for the chlorine system are documented, and it is operated within these safe ranges. A hazard review has been conducted for the chlorine system and identified action items are expected to be completed by December 31, 2002. When a major process change is made to the system, there are procedures in place to conduct a hazard review. Otherwise, a hazard review is conducted every five years. Written procedures for the operation and maintenance of the chlorine sys tem are also in place for the Loeb Facility. Procedures are reviewed and updated periodically by City personnel and whenever a major process change occurs. Loeb Facility operators receive training in the operation of the chlorine system through classes and on-the-job instruction. Competency is determined through supervisor observation, operator demonstration of activities, and written and oral tests. Operators receive refresher training at least every three years, or more often as necessary. Only qualified operators operate the chlorine system. A team of City personnel conducts a compliance audit of the facility operations and procedures once every three years and whenever a major process modification is made. A compliance audit checklist has been developed based on American Water Works Association recommendations. A system to correct any deficiency discovered during the compliance audit is in place. In the event of an accidental release, or a situation that could lead to an a ccidental release, there are procedures in place to investigate such incidents, develop findings and recommendations for corrective action, and implement the recommendations. Personnel working at the Loeb facility are trained to notify emergency personnel in the event of a significant chlorine leak. In the unlikely event a chlorine release requiring the assistance of offsite emergency response personnel occurs, the City of Beaumont Fire Department is responsible for responding to the accident, coordinating the emergency response effort, and notifying potentially affected areas in the surrounding community. |