City of North Bend Wastewater Treatment Plant - Executive Summary
Regulatory Substance Handled: Chlorine - for the disinfection of wastewater treatment plant effluent. |
Accidental Release Prevention Policy; We use chlorine for the disinfection of treated municipal effluent. It is used because it is effective and economical to use. It is our intention to reduce the chances of an accidental release by reducing the amount of chlorine on site with the consideration of trying to limit the number of times we handled the chlorine. The city intends to use safety equipment that includes vacuum regulators, chlorine alarms, and physical guarding to help limit the chances of an accident. We also intend to do the following;
1. To operate and maintain equipment in a diligent manner.
2. To train operators on loading & unloading of chlorine cylinders, hook up of cylinders, and a complete
understanding of the chlorination system.
3. Maintain a preventative maintenance program.
Worst Case Scenario;
A chlorine leak in a horizontal 1 ton cylinder. The ta
nk is 70% full. The opening of the leak is .36" in diameter, and 1" from the tank bottom. The release last 12 minutes at a rate of 201 lbs/min. At 3 ppm the Max. threat zone is 1.2 miles to the end point.
Alternative Release Scenario;
A chlorine gas leak is located in a pipe that is .4 inches in diameter and 8' long. The size of the hole is .13 sq. inches. Max. release rate equals 6.52 lbs./min. The total amount of gas released is 391 lbs. Limited duration is 1 hour. At 3 ppm the Max. threat zone is 354 yards.
5 Year Accident History; No accidents to report.
The City of North Bend Wastewater Treatment Plant Staff does not respond to major chlorine leaks and will evacuate area. The plant staff will react to minor leaks in piping etc. A second person always stands by during exchanging of cylinders. If a minor leak develops the second person (with SCBA) enters area and shuts off valve on container. Operator then uses AQUA-AMMONIA to locate leaks.
e leak: If a moderate leak occurs (a visual could develops but leak isolated) The North Bend Fire & Police Dispatch will be notified for the purpose of informing the public.
Major leak; If a major leak occurs then the Coos Bay Hazmat team witll be the first responders. Then 911 would be called. The Oregon Accident Response System at 1-800-452-0311 would then be notified.