E. Morgan Stickney Water Treatment Facility - Executive Summary |
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The Mobile Area Water and Sewer System (MAWSS) operates the E. Morgan Stickney Water Treatment Facility located at 4800 Moffat Road in Mobile, Alabama. At the treatment plant, the facility stores approximately eight (8) one-ton cylinders of chlorine. The one-ton cylinders are used on-site as a disinfectant in the treatment of the incoming surface water. The E. Morgan Stickney facility has a maximum of 10 and a minimum of 3 on duty at any one time. Daily inspections of the areas storing and/or using chlorine are conducted by the facility employees. The area that stores the one-ton cylinders is fully enclosed and is equipped with a caustic scrubber for control of a chlorine release. The caustic scrubber system is equipped with chlorine detectors that will automatically activate the scrubber system if a chlorine concentration of 3 ppm or greater is present. In addition, MAWSS has installed an emergency chlorine valve actuator, which will shut off the chlorine being supplied from the cyli nders within 1.5 seconds after detecting a leak. In preparation of the Risk Management Plan (RMP), both worst-case and alternative scenarios were considered. Under worst-case scenario conditions, a catostrophic event would occur releasing a full one-ton cylinder. The radius of the potentially impacted surrounding area would be 1.3 miles. This scenario is highly improbable and did not consider the mitigation of a release by the enclosure, the chlorine valve actuator, or the scrubber system. A more probable release event would occur if a transfer hose connecting the chlorine cylinder to the chlorinator was to fail. This scenario was the alternative scenario considered in the development of the RMP. This release event would have a potential impact radius of less than 0.06 miles from the site. This scenario accounted for the mitigation factors inherent by the enclosed building, an operable caustic scrubber system, and the functioning chlorine valve actuator. The E. Morgan Stickney fac ility has not had an an accidental release in the last five (5) years. In the event a significant releases occurs, the Mobile County Emergency Management Agency (MCEMA) would be notified immediately to respond. The MCEMA would dispatch experienced HAZMAT personnel appropriately trained to handle such situations. |