City of Emory Water Treatment Plant - Executive Summary
The City of Emory is a town of approximately 960 people located in Rains County, Texas. It is governed by a City Council. The city owns a water treatment plant and a wastewater treatment plant and these are overseen by the Public Works Director. A Risk Management Plan and Program were necessary because the city stores more than 2500 lbs. of chlorine at the water treatment plant, located on the edge of Lake Tawakoni, off of Free Bridge Road. |
The City of Emory's water treatment plant uses chlorine to treat potable water. At any point in time, there could be a maximum of 4,050 pounds of chlorine stored at the plant in 27 - 150 pound cylinders. These cylinders are chained to the chlorine building outside when not in use and locked inside the chlorine room when in use. All plant operators are trained as to the dangers of chlorine and safe handling practices.
The Public Works Director is responsible for carrying out the risk management program. He and the plant operator share the responsib
ilities of the plan. These positions are full-time, and there are several other part-time operators who are on-call on the weekends.
The City has determined the worst case release scenario to be the complete release of one 150 lb. cylinder within 10 minutes as per the ALOHA model used by the AWWA in the Compliance Guidance & Model RMProgram for Water Treatment Plants. Chlorine gas is estimated to travel up to a 1.33 mile radius around the facility. Approximately 250 people would be affected by this release. There are no large public receptors or environmental receptors within the radius. There may be some people using the adjacent lake for recreation who will need to be warned in the event of a release. The emergency response team is prepared for a release of this size and has participated in a mock release event. The alternative scenarios, failure of a valve to close and a sheared valve, release 17.1 lbs. over .11 miles and 81 lbs. over .96 miles, respectively. These releases would a
ffect 20 and 200 people. The emergency response team is prepared to handle these releases as well. The city will soon be installing an alarm system which will alert emergency responders if a chlorine leak occurs.
There have been no reportable releases within the past five years or as long as anyone at the city can remember.
Emory WTP operators are licensed by the Texas Natural Resource Conservation Commission and also trained by the Public Works Director on site-specific activities. Operators attend continuing education seminars as required by their licenses. As safety measures, operators are not allowed to change chlorine tanks without a back-up man present, and are subject for dismissal if they do so. Operators follow written operation and maintenance procedures developed both by manufacturers and by the Public Works Director.
Emergency response will be handled by the City of Emory Fire Department using the City of East Tawakoni Fire Department as back-up if necessary. The fire de
partment is prepared with PPE in case of a chlorine release. A system is in place to roadblock all entry streets to the facility and an evacuation plan is in place. Flyers have been prepared and distributed alerting residents of the danges associated with chlorine. Evacuation routes and locations of safety were noted. These flyers as well as a warning of a relase will also be handed out by fire fighters in the event of an actual release. Flyers are the preferred means of communication so that fire fighters do not have to remove their gas masks at each house. City employees will not be involved in emergency response, however, they were present at the mock release and have been trained to leave the area immediately and alert emergency responders. Face masks are located outside the chlorine room in order for operators to be protected while leaving the facility.
The city has developed an incident investigation plan which will be the responsibility of the public works director. This plan w
as modeled after the AWWA Compliance guidance for Water Treatment Plants. This plan is part of the Risk Management Program developed by the city in early 1998.
Within the next few months, an alarm system will be installed to alert emergency responders in the event of a chlorine leak. In addition, a barrier will be set up to protect cylinders stored outside from damage due to vehicle impact. A windsock has been added for emergency response assistance and additional warning signs have been added outside and inside the chlorine room.