City Lake Chlorination Facility - Executive Summary
General Executive Summary for the City of Port Townsend's Use of Chlorine in Water Treatment |
1. Accidental Release Prevention and Emergency Response Policies
The City of Port Townsend is strongly committed to employee, public and environmental safety. This commitment is inherent to a comprehensive accidental release prevention program in place that covers areas such as design, installation, operating procedures, maintenance, and employee training associated with the processes at our facility. It is our policy to implement appropriate controls to prevent possible releases of regulated substances. In the unlikely event of a release, we have arranged with Jefferson County Department of Emergency Management and local fire departments to provide emergency response coordination and will request CHLOREP emergency response personnel to control and mitigate the effects of the release.
2. The Stationary Source and the Regulated Substances Handled
We have one regulated substance, chlorin
e gas, at the City Lake facility. Chlorine is used in the water treatment process for disinfection of the public water supply. The maximum inventory of chlorine at our facility is 12,600 lbs.
3. The Worst Case Release Scenario and the Alternative Release Scenarios, including administrative controls and mitigation measures to limit the distances for each reported scenario
To perform the required offsite consequence analysis for our facility, we have used RMP*Comp provided by the EPA. The following paragraphs provide details of the chosen scenarios.
The worst case release scenario submitted for Program 3 toxic substances as a class involves a catastrophic release from a 150 lb. chlorine cylinder due to a sheared valve. This would involve the release of 150 lb. of chlorine in a gaseous form over 10 minutes. Under worst case weather conditions, namely Class F atmospheric stability and 1.5 m/s windspeed, a maximum distance of 1.2 miles is obtained, corresponding to a toxic endpoin
t of 0.0087 mg/L.
The alternative release scenario for chlorine present in Program 3 processes involves a release from a process pipe leak. This scenario involves the release of 500 lb. of chlorine in a gaseous form over 60 minutes before containment of the leak. Under Class F weather conditions, the maximum distance to the toxic endpoint of 0.0087 rng/L is 0.3 miles.
4. The General Accidental Release Prevention Program and the Chemical-Specific Prevention Steps
Our facility has taken all the necessary steps to comply with the accidental release prevention requirements set out under 40 CFR part 68 of the EPA. The following sections briefly describe the elements of our release prevention program that are in place at our stationary source.
Process Safety Information
The City of Port Townsend maintains a detailed record of written safety information that describes the chemical hazards, operating parameters and equipment designs associated with the water treatment process.
ocess Hazard Analysis
Our facility conducts comprehensive studies to ensure that hazards associated with our process are identified and controlled efficiently. The methodology used to carry out these analyses is a What If/Checklist. The studies are undertaken by a team of qualified personnel with expertise in process operations and are revalidated at a regular interval of at least once every 5 years. Any findings related to the hazard analysis are addressed in a timely manner.
For the purposes of safely conducting activities within our covered process, the City of Port Townsend maintains written operating procedures. These procedures address various modes of operation such as initial startup, normal operations, temporary operations, emergency shutdown, emergency operations and normal shutdown. The information is regularly reviewed and is readily accessible to operators involved with the process.
The City of Port Townsend has a comprehensive
training program in place to ensure that employees that are operating the process are completely competent in the operating procedures associated with this process. New employees receive basic training in process operations followed by on-the-job supervision until they are deemed competent to work independently. Refresher training is provided at least once every 3 years and more frequently as needed.
The City of Port Townsend carries out documented maintenance checks on process equipment to ensure proper function. Process equipment examined by these checks includes among others; cylinders, piping systems, relief and vent systems, monitoring equipment, regulators and pumps. Maintenance operations are carried out by qualified personnel with training in maintenance practices. Furthermore, these personnel are offered specialized training as needed. Any equipment deficiencies identified by the maintenance checks are corrected in a safe and timely manner.
nagement of Change
Written procedures are in place for the City Lake facility to manage changes in process chemicals, technology, equipment and procedures. Process operators/maintenance personnel whose job tasks are affected by a modification in process conditions are promptly made aware of and offered training to deal with the modification.
Pre-start up safety reviews related to modifications in the established process are conducted as necessary. These reviews are conducted to confirm that construction, equipment, operating and maintenance procedures are suitable for safe startup prior to placing equipment into operation.
The City of Port Townsend conducts audits on a regular basis to determine whether the provisions set out under the RMP rule are being implemented. These audits are carried out at least once every 3 years and any corrective actions required as a result of the audits are undertaken in a safe and prompt manner.
While the City of Port Townsend has never had a catastrophic release incident, it will promptly investigate any incident that resulted in, or could reasonably result in a catastrophic release of a regulated substance. These investigations will be undertaken to identify the situation leading to the incident as well as any corrective actions to prevent the release from reoccurring. All reports will be retained for a minimum of 5 years.
The City of Port Townsend believes that process safety management and accident prevention is a team effort. City employees are strongly encouraged to express their views concerning accident prevention issues and to recommend improvements. In addition, our employees have access to all information created as part of the facility's implementation to the RMP rule.
On occasion, the City hires contractors to conduct specialized maintenance and construction activities. Prior to selecting a contractor
, a thorough evaluation of safety performance of the contractor is carried out. The City of Port Townsend has a strict policy of informing the contractors of known potential hazards related the contractor's work and the process. Contractors are also informed of all the procedures for emergency response should an accidental release of a regulated substance occur.
5. Five-year Accident History
The City of Port Townsend has had an excellent record of preventing accidental releases over the last 5 years. Due to our stringent operational and safety prevention policies, there has been no accidental release during this period.
6. Emergency Response Plan
The City of Port Townsend has coordinated with the Jefferson County Department of Emergency Services and local fire departments for emergency response assistance. Assistance for containing an accidental chlorine gas release will be provided by the chlorine supplier. Jefferson County Emergency Services has overall responsibility fo
r emergency response coordination. Planning aspects of emergency response including adequate first aid and medical treatment, evacuations, and notification of local emergency response agencies and the public. The plan will be promptly updated to reflect any pertinent changes taking place within our process that would require a modified emergency response.
7. Planned Changes to Improve Safety
Several developments and findings have resulted from the implementation of the various elements of our accidental release prevention program. Replacing a wooden storage building, improving lighting and clearing trees for windfall and fire protection are some of the steps we want to take to improve safety at our facility. These changes are expected to be implemented by August 1999.