Thomas C. Green Water Treatment Plant - Executive Summary

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The accidental release prevention and emergency response policies at the facility: 
The City of Austin Water & Wastewater Utility (Utility) owns and operates the Thomas C. Green Water Treatment Plant.  The Utility's mission is that it will protect our community's public health and environment by effective management of our water resources.   
The Green Water Treatment Plant has established an effective chemical release prevention and emergency response plan.  It is the policy of the Green Water Treatment Plant to take all necessary actions to prevent the release of a hazardous chemical.  Even with an effective prevention program in place, a chemical release incident may still be a remote possibility.  Through planning, procedures, training, monitoring, and mitigation systems, the facility is prepared to promptly perform emergency actions to minimize and cont 
ain the release of a hazardous chemical.   Highly trained Green Water Treatment Plant technicians with the aid of City of Austin Fire Department Hazardous Materials Team are prepared to respond to the scene, evacuate the immediate area (if necessary), and control a release.  
The facility and the regulated substance handled: 
The Green Water Treatment Plant provides safe drinking water to citizens, businesses, and industries of the City of Austin.  In the process of producing safe drinking water, the regulated chemical, chlorine, is used and stored at the facility to disinfect the water from microbial contamination.  Chlorine liquefied under pressure is delivered in one ton containers.  A maximum of 18 containers are stored in a specially designed storage building.  The administrative controls placed on the amount of chemicals stored on-site allow the facility to maintain safe operating and design conditions. 
The worst-case release scenario(s) and the alternative release scenario(s): 
The Environmental Protection Agency (EPA) defines a "worse-case" scenario as the release over a 10- minute period of the largest amount of a listed chemical under very extreme weather conditions and with the total, simultaneous failure of all active safety and emergency backup systems and personnel.  The probability of this scenario is so extremely remote that EPA's basic intention is to identify any potential offsite impacts.  The facility defines its worst case scenario as the total release of a one ton chlorine cylinder due to impact without consideration of an enclosure or other mitigation system.  The EPA developed model, RMP* Comp Version 1.06, was used to calculate endpoint distances as reported in the plan.  The facility reports that the potential for offsite public and environment impact exists. 
The EPA requires facilities to plan for more realistic "alternative-release" scenarios.  The EPA characterizes an alternative release scenario as "more likely to occur than the worst 
-case scenario" and allows sites to include active and passive control/mitigation systems and more realistic weather conditions in the assumptions.  
The chlorine storage building is specifically designed to limit the release of the process chemical.  The design includes both active and passive mitigation systems.  The passive mitigation systems include enclosures and sumps.  The active mitigation systems include sprinkler and scrubber systems.  The process controls used include alarms, gas leak detection systems, automatic/manual shut-off, and emergency power.  The facility defines an alternative case scenario for chlorine as a flexible tubing leak occurring inside the storage building with the consideration of active and passive mitigation systems.  Active and passive mitigation systems are design to contain or neutralize the alternative scenario release. The EPA developed model, RMP* Comp Version 1.06, was used to calculate endpoint distances as reported in the plan.  Due to the mod 
eling software's minimum reportable distance requirement of 0.1 miles, the facility chooses to report that offsite public impact exists.   
The general accidental release prevention program and chemical-specific prevention steps: 
Green Water Treatment Plant complies with the Rules and Regulations for Public Water Systems issued by the Texas Natural Resource Conservation Commission (TNRCC).  The rules require water treatment plants to be operated under the supervision of licensed personnel. The rules also require the facility to construct, maintain, and operate the chemical facilities in accordance with OSHA, ASTM, ANSI, and ASME Standards.  These rules are intended to ensure safe operation of the facility.   
The Green Water Treatment Plant has established a comprehensive accidental release prevention program.  The prevention program is intended to assure that facility designs and procedures are reviewed and conform to safe design principles and practices.  The operations, maintenance 
, and training program elements assure that the processes are within the safe design and operating conditions.  Highly trained employees are on duty 24 hours per day to inspect, maintain, and operate the process chemical systems.  Operational, maintenance, and emergency response procedures are periodically reviewed and updated.  The facility has an established training program that consists of classroom, on-the-job, and demonstration training.  The facility has an established maintenance program that requires equipment identification, testing and inspections, preventative maintenance, training, and documentation.  This is accomplished with the assistance of Year 2000 compliant maintenance software. 
The five-year history: 
The facility has not had an accidental release of any regulated chemical (chlorine) in the past five years.  No documented offsite injuries or environmental impacts have occurred due to a chemical release in the 75-year history of the facility's operation. 
The emerg 
ency response program: 
The Green Water Treatment Plant has established an emergency response program which involves training of employees and a partnership arrangement with the Austin Fire Department Hazardous Materials (AFD HazMat) Team.  The Utility has spent considerable time, money, and effort to train every employee at the facility to respond to a chemical release.  All facility employees have received Hazardous Waste Operations and Emergency Response (HAZWOPER) awareness, operations, or technician level training.  Selected employees have received extensive training in emergency response from AFD HazMat instructors equal to that received by the HazMat Team.  In case of a hazardous chemical release, the facility operators would determine the severity of the situation and if warranted, would call the HazMat team to respond to the facility.  After an assessment of the situation has been made by AFD and facility personnel, a partnered response to alleviate the problem would be perfor 
med. This partnership makes the best use of the expertise of facility employees and HazMat team.  The Austin Office of Emergency Management would notify citizens via television and radio broadcast of the hazard.   
Planned changes to improve safety: 
The Green Water Treatment Plant has recently completed modifications to the chlorine process, which upgraded the safety systems in the chlorine storage building.  The facility is continuously evaluating new safety systems, process control equipment, and procedures that would improve the safety of the employees, the public, and the environment.
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