Hattiesburg Water Plant #2 - Executive Summary |
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RMP Executive Summary for Hattiesburg Mississippis Water Plant #2 A. The Hattiesburg Water & Sewer Department accidental release prevention policy involves operational procedures, management practices and continued training to prevent accidental releases. Continued improvement of facilities and procedures will reduce accidental releases. The emergency response policy involves procedures to notify and coordinate response with local responders. B. Water Plant #2 is one of two water treatment plants that provides drinking water to the City of Hattiesburg, Mississippi. Chlorine gas is used to disinfect the drinking water supply at this location. This plant is located in the southeastern section of the city at 900 James Street. The maximum amount of chlorine at this facility would be four one-ton containers. This facility has at least one water treatment plant operator on site 24 hours a day, 365 days per year. These operators can respond to any trouble that may occur. C. The offsite consequence analysis includes consideration of two chlorine release scenarios, identified as worst case release scenario and alternative scenario. Both scenarios were calculated using EPAs RMP*Comp software. The worst case release scenario involves a failure of a one ton chlorine cylinder with a 10 minute release duration and a release rate of 110 pounds per minute. This scenario involves a release in an enclosed space, in direct contact with outside air. The offsite consequences of this scenario are as follows: 1. Topography: Urban surroundings (many obstacles in the immediate area) 2. Toxic Endpoint: 0.0087 mg/L; basis: ERPG-2 3. Estimated Distance to Toxic Endpoint: 0.9 miles (1.4 kilometers) 4. Residential population estimate: 2000 The meteorological assumptions about this scenario are: Wind Speed: 1.5 meters/second (3.4 miles/hour) Stability Class: F Air Temperature: 77 degrees F (25 degrees C) The alternative release scenario involves a tubing failur e, bad connection, or valve failure resulting in a release duration of 60 minutes. The maximum average sustained release rate for this scenario would be 11 pounds per minute. The offsite consequences of this scenario are as follows: 1. Topography: Urban surroundings (many obstacles in the immediate area) 2. Toxic Endpoint: 0.0087 mg/L; basis: ERPG-2 3. Estimated Distance to Toxic Endpoint: 0.1 miles (0.2 kilometers) 4. Residential population estimate: 50 The meteorological assumptions about this scenario are: Wind Speed: 3 meters/second (6.7 miles/hour) Stability Class: D Air Temperature: 77 degrees F (25 degrees C) D.The accidental release prevention program is based on the following elements: 1. Training of operators 2. Preventive maintenance program 3. Use of process and safety equipment 4. Use of effective operating procedures 5. Reviews of operational procedures, training, hazards and safety information Chemical specific prevention steps include the availabili ty of self contained breathing apparatus and awareness of the hazards and toxic properties of chlorine. E. No accidental releases of chlorine have occurred at this facility in the past five years. F. Our facilities are included in a community emergency response plan. Our employees will not respond to an accidental release other than notify the Hattiesburg Fire Department. Emergency response will be handled by the Hattiesburg Fire Departments Hazard Incident Response Team. G.Construction has begun on a chlorine storage building at Water Plant #2 to keep chlorine cylinders out of direct sunlight and to house chlorination equipment. This building will have chlorine leak detectors installed to alert operators of accidental chlorine releases. Internal training as well as training by outside sources are planned on a regular basis. |