Tolk 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 Southwestern Public Service (SPS) Tolk Station. 
Prevention and Response Policies 
The accidental release prevention and emergency response policies are represented in the Emergency Planning and Response Sections of the Tolk Station PSM/RMP manual for the chlorine system.  SPS 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, SPS 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. 
SPS management understands its duty to provide a safe working environment and to take measures to prevent accidents that may have an effect on the surrounding 
community.  This understanding is reflected in procedures described and referenced in the RMP manual. 
Stationary Source and Regulated Substances 
Tolk 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.  The plant has two regulated chlorine systems each with a maximum intended inventory of 2 containers (or 4000 pounds each).   
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 toxic endpoints.  For chlorine, a distance of 3.0 miles to the toxic endpoint was determined for a release of 2000 pounds in ten minutes.  This determination is applicable for both systems, with the same "circle" of influence from a worst-case release from either system. 
The alternative release scenario for chlorine consists of a release of 313 pounds of chlorine over a one-hour period due to a severed 5/16 inch valve on the one-ton container.  No active mitigation devices were considered to influence the release scenario.  A distance of 0.1 miles to the toxic endpoint was determined.  This determination is applicable for both systems, with the same "circle" of influence from an alternative release from either system. 
Prevention Steps for Chlorine System 
The prevention program and chemical-specific prevention steps are described in detail in the Tolk Station Chlorine System PSM/RMP manual.  The preve 
ntion programs include 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 programs, as well as ready access to program information 
7 Process safety information, which has been collated into the PSM/RMP manuals located at the Tolk Station 
7 Process hazard analysis (PHA) - A PHA on the chlorine system was conducted in February 1999.  All recommendations from the PHA have been, or are being, addressed. 
7 Operating procedures for the chlorine process, which are included in the system PSM/RMP manuals 
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 systems 
7 Pre-startup safety review procedure for implementation for significant system changes to ensure that the construction and equipment installation is according to desi 
gn 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 
7 Mechanical integrity program through the facility CMMS system to ensure that the chlorine system equipment is maintained in good and safe working condition.  The plant undertakes inspections of chlorine system equipment three times per week, as well as more significant inspections and tests on system components at frequencies determined by compliance with recommendations of the Chlorine Institute and system component manufacturers.  The most recent date of a major test is included in this submittal. 
7 Hot work procedures to require the evacuation of the regulated chemicals from the system equipment (using the Tolk Station Clearance Procedures before hot work is performed on the chlorine system 
7 Management of change program to ensure that proposed system changes are comprehensively evaluated before 
implementing the change 
7 Incident investigation procedures for the investigation of any catastrophic (or potentially catastrophic) incident associated with the chlorine system, using the SPS Root Cause Investigation System 
7 Compliance audits to be conducted at least once every three years to ensure the continued compliance of the Tolk Station chlorine PSM/RMP program. 
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. 
Emergency Response Program 
This facility has established and maintains an emergency response program that is coordinated with local response agencies and includes emergency response by an on-site response team backed up by the Muleshoe Fire Department and the SPS Plant X Emergency Response Team.  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 Tolk 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 prev 
enting 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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