Comanche Station - Executive Summary

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This executive summary is a brief overview of the Risk Management Program and the associated policies at the Public Service Company of Colorado (PSC) Comanche Station. 
Prevention and Response Policies 
The accidental release prevention and emergency response policies are represented in the Emergency Planning and Response Sections of the Comanche Station PSM/RMP manual for the chlorine system. PSC takes an active role in preventing accidental releases at all of its facilities by ensuring that its employees are properly trained in the safe operation of covered processes and the safe handling of treatment chemicals.  As for emergency response, PSC has established and maintained procedures for emergency notification and response.  These are reviewed with employees on a periodic basis and revised to accommodate changes in staffing when they occur. 
PSC management understands its duty to provide a safe working environment and to take measures to prevent accidents that may have an effect on t 
he surrounding community.  This understanding is reflected in procedures described and referenced in the PSM/RMP manual. 
Stationary Source and Regulated Substances 
Comanche Station is a coal-burning electric generating station.  The regulated substance handled at this facility is chlorine.  The chlorine is used for cooling and process water biocidal control and is stored in one-ton containers with a maximum intended inventory of 4 containers (8,000 lbs.) on site.  The facility is planning to install a new chlorine system, which is projected to be in operation by July 1, 1999.  This system will employ use of reduced chlorinator rating from the existing system (from 3000 ppd to 1000 ppd) which will allow for better system control.  All applicable provisions of the Management of Change procedures will be implemented, to include revision of the operating procedures, training program, process safety information, etc.  A pre-startup safety review will be conducted prior to startup of the ne 
w system. 
Release Scenarios 
Worst-case and alternative release scenarios have been determined after careful review of the regulation and consideration of the storage vessel configuration at the facility.  For worst-case release scenario, the regulation is clear.  The assumption is that the single largest container of a regulated substance (one-ton container of chlorine) is released over a ten-minute period.  No active mitigation may be considered.  Worst-case meteorological conditions are also assumed to be present.  The RMP*Comp air dispersion model was used to determine distances to the toxic endpoint.  A distance of 3.0 miles to the toxic endpoint was calculated for a release of 2000 pounds in ten minutes. 
The alternative release scenario for chlorine consists of a release of 959 pounds of chlorine over a one-hour period due to a severed pigtail on the one-ton container.  No active mitigation devices were considered to influence the release scenario.  A distance of 0.7 miles to th 
e toxic endpoint was determined. 
Prevention Steps for Chlorine 
The prevention program and chemical-specific prevention steps are described in detail in the Comanche Station Chlorine System PSM/RMP manual.  As indicated above, the facility will be installing a new chlorine system (to replace the existing system), which is anticipated to be in operation by July 1, 1999.  All applicable provisions of the Management of Change procedures will be implemented, to include revision of the operating procedures, training program, mechanical integrity procedures, process safety information, etc.  All components of the RMP program will be in place and a pre-startup safety review will be conducted prior to starup of the new system. 
The prevention program includes the following elements: 
7 Employee participation, which includes provisions for active participation by plant employees in the development and implementation of the plant PSM/RMP program, as well as ready access to program information 
7 P 
rocess safety information, which has been collected in the Comanche Station Document Storage Room and summarized in the PSM/RMP manual 
7 Process hazard analyses (PHAs) - The initial PHA for the chlorine system was conducted in 1994;  the PHA was updated in February 1997.  All recommendations from the PHAs have been, or are being, addressed.  The aforementioned new system is being installed as a result of recommendations of the earlier PHAs;  a PHA on the new system design was conducted in April 1999. 
7 Operating procedures for the chlorine process, which are included in the Comanche Station Chlorine System PSM/RMP Manual 
7 Training for all personnel involved in the operation and maintenance of the chlorine system 
7 Contractor management policy, which is not to allow contractors to operate or maintain the chlorine system once installed 
7 Pre-startup safety review procedure for implementation for significant system changes to ensure that the construction and equipment installation is acc 
ording to design specifications, appropriate procedures are in place and accurate, a PHA has been done and the recommendations resolved, and employees are trained prior to startup of the modified system.  A PSSR will be completed prior to startup of the new system by or during July 1999. 
7 Mechanical integrity program through the facility SSR system to ensure that the chlorine system equipment is maintained in good and safe working condition.  Facility personnel conduct daily visual inspections of the chlorine system.  The date and equipment included in 7.7 b and c address the most recent major PM activity. 
7 Hot work procedures to require the evacuation of the regulated chemicals from the system equipment (using the Comanche Station Maintenance Clearance Procedures) before hot work is performed on the chlorine system 
7 Management of change (MOC) program to ensure that proposed system changes are comprehensively evaluated before implementing the change.  MOC procedures are being employ 
ed to address the installation of the new system by or during July 1999. 
7 Incident investigation procedures for the investigation of any catastrophic (or potentially catastrophic) incident associated with the chlorine system, using the PSCo Root Cause Investigation Report form.  An incident investigation was conducted in 1997 following a release of 30 pounds of chlorine, and the recommendations from the investigation team have been addressed. 
7 Compliance audits to be conducted at least once every three years to ensure the continued compliance of the Comanche Station chlorine PSM/RMP program.  A PSM audit was conducted on the chlorine process in 1996;  a PSM/RMP audit was conducted in 1999.  All audit findings have been, or are being, addressed. 
7 Trade secrets provisions allowing contractors and employees or their representatives access to system information 
Accident History 
Within the five-year period prior to the submittal of this RMP, there were no accidental releases of chlorine 
meeting the requirements of 40 CFR 68.42.  However, the facility did have a release of 30 pounds of chlorine on July 16, 1997, to which emergency personnel were required to respond.  There were no injuries associated with the leak and/.or the response to secure the container for transport, but the release was reported to the National Response Center and the Colorado Department of Public Health and Environment.  An incident investigation was conducted, and indicated that additional operator training for connecting the containers to the manifold should be performed and that an evaluation of the connections to the chlorine container be conducted to determine if they needed to be modified.  These recommendations have been addressed. 
Emergency Response Program 
This facility has established and maintains an emergency response program that is coordinated with local response agencies.  The program is described in detail in the Emergency Planning and Response section of the PSM/RMP compliance 
manual and meets the requirement of 40 CFR 68.95.  The goals of the program are to protect onsite employees from the hazardous effects of chemical releases and to minimize the effects of releases on the general public.  The program is routinely reviewed and updated to reflect personnel and regulatory changes. 
Planned Changes for Improved Safety 
Ideas for changes to improve safety are actively sought from employees.  Employee safety meetings that focus on chemical safety issues are held regularly at this facility.  Employees are encouraged and trained to recognize hazards and present ideas to eliminate them or to minimize the potential consequences of those hazards. 
During the development of the Comanche Station PSM/RMP program, process hazard analyses were conducted with key employees to meet the prevention program requirements.  During these sessions, recommendations were made for the purpose of improving safety and preventing accidental chemical releases.  Each recommendation has  
been or will be considered for implementation.  Though not all recommendations may be implemented, all will be considered.  The exercise has provided all affected employees with a heightened awareness of safety issues related to the covered processes.
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