Reservoir 7 - Executive Summary

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El Dorado Irrigation District has instituted a Risk Management Program for their water treatment and chlorine receiving and storage facility, Reservoir 7, as required by Federal Accidental Release Prevention (ARP) Program regulations at 40 CFR Part 68.  The Risk Management Program identifies the equipment, procedures, maintenance, inspection, and training associated with Regulated Substances (RS's) handled at this facility in excess of Federal threshold quantities; describes the structured assessment of hazards which was conducted to assess possible effects on employees and offsite public and environmental receptors; provides the results of an offsite consequences analysis; defines a prevention program, emergency response program, and mitigation measures to reduce the probability and magnitude of accidental releases of RS's; and establishes a schedule and responsibilities for implementation of mitigation measures and auditing of program elements.  This Risk Management Plan (RMP) is bei 
ng filed as required by ARP regulations in order to report the elements of the current Risk Management Program and to describe further measures planned to mitigate or prevent accidental releases of RS's.   
 
STATIONARY SOURCE AND REGULATED SUBSTANCES HANDLED 
 
El Dorado Irrigation District provides water supply and distribution in El Dorado County.  Its water treatment facility, Reservoir7, is located off of Oak Hill Road and Pleasant Valley Road, Diamond Springs, CA in El Dorado County. This facility uses chlorine, a RS, for disinfection in quantities greater than the Federal threshold quantity for this RS, and additionally is used for warehousing in quantities greater than the Federal threshold quantity for this RS. The facility is located near Hanks Exchange.  There are no full-time employees at this site.  Operators visit the site daily and also respond to alarm conditions.   
 
Chlorine is received in ton containers by truck, handled with an electric hoist, and stored on ton container 
scales inside the building.  The chlorine is used to control biological growth on the filters and to disinfect the treated water.  Pressurized chlorine gas within a ton container is reduced to vacuum at a vacuum regulator valve mounted directly onto the ton container's gas valve.  From there, the chlorine under vacuum is metered through rate valves and rotameters, and drawn into water solution by the passage of pressurized water through an injector.  
 
Chlorine is also received in 150# cylinders, for use at small chlorination facilities throughout the EID service area. These cylinders are delivered by the chemical supplier and placed in storage until EID personnel retrieve and transport up to six cylinders at a time via the EID 3/4 ton pickup truck for use at the remote sites. 
 
ACCIDENTAL RELEASE PREVENTION AND EMERGENCY RESPONSE POLICIES 
 
It is the policy of El Dorado Irrigation District that the receipt, storage and handling of chlorine at its facility be done in a manner which meets 
regulatory requirements and minimizes the probability and severity of accidental releases of chlorine to the atmosphere, in order to protect the health and safety of its workers, the public, and the environment.  In order to accomplish this goal, El Dorado Irrigation District has gathered safety information on chlorine and on the process, equipment and procedures involving chlorine; performed a structured assessment of hazards of the process and external events which might affect the process; performed an offsite consequences analysis of defined release scenarios; established a written program for prevention and mitigation of accidental releases; and established a written emergency response program coordinated with emergency response agencies. 
 
WORST CASE RELEASE SCENARIO 
 
A single "worst case" release scenario is required to be considered for each stationary source, resulting in the maximum distance to an endpoint for all toxic RS's contained on site above the threshold quantity. 
The 
worst case release scenario for toxic chemicals is defined in the ARP regulations as the release of the contents of the largest single container of RS (in this case chlorine) over a period of 10 minutes. The scenario considered the release of the contents of the largest container of chlorine on site, in this case, 2,000 lb.  This release scenario is not physically possible, due to the characteristics of chlorine. 
 
ALTERNATIVE CASE RELEASE SCENARIO 
 
An "alternative case" release scenario is required to be considered for each toxic RS handled in quantities greater than the threshold quantity at the site. The "alternative case" scenario is described in the ARP regulations as a likely release resulting in offsite effects, considering administrative controls and mitigation measures in place, and is to be determined by the facility operators as part of the Process Hazard Analysis required to be performed during RMP development.  The "alternative case" considered for this facility is the rel 
ease of chlorine from a 150# cylinder, due to the cylinder being dropped during storage operations or delivery, with the release secured by the responder through application of a Type "A" Cylinder Repair Kit after one hour. 
 
ADMINISTRATIVE CONTROLS 
 
Administrative controls in effect at El Dorado Irrigation District which were considered to mitigate the severity of the Worst Case and Alternative Case release scenarios include El Dorado Irrigation District's written policies and procedures for training of operators and maintenance personnel, written procedures for control of the inventory of chlorine at the facility, and policies regarding quality level of replacement materials and components for the chlorine system. 
 
MITIGATION MEASURES 
 
No mitigation measures were considered to limit the severity of the Worst Case scenario.  No passive mitigation measures were considered to limit the severity of the Alternative Case scenario.  Active mitigation was considered for the Alternative Case,  
in the form of the timely response of properly trained and equipped personnel following established emergency response procedures. 
 
GENERAL ACCIDENTAL RELEASE PREVENTION PROGRAMS 
 
General accidental release prevention programs instituted by El Dorado Irrigation District are categorized as administrative (management) programs; procedures, training, and engineering controls; and emergency response programs. 
 
El Dorado Irrigation District has instituted a Process Safety Management (PSM) Program meeting OSHA requirements at 29 CFR 1910.119 covering its disinfection and warehousing processes at this site.  This constitutes the general accidental release prevention program for El Dorado Irrigation District's operations.  The program and document management procedures included in the PSM Program will be used as the management system for the Risk Management Program. 
 
CHEMICAL-SPECIFIC RELEASE PREVENTION STEPS 
 
Release prevention steps specific to chlorine have been identified and implemented.  
These include, among other things, the installation of a stanchion set for securing 150-lb. cylinders on the lift gate of the EID transfer truck, and creation of numerous facility-specific operation procedures with check boxes for completion of critical steps. 
 
FIVE YEAR ACCIDENT HISTORY 
 
There have been no accidents involving chlorine at this facility within the past five years resulting in injuries or offsite consequences. 
 
EMERGENCY RESPONSE PROGRAM 
 
El Dorado Irrigation District's Emergency Response Program applicable to chlorine has been coordinated with the El Dorado County Department of Environmental Health, the local agency responsible for hazardous materials inventory reporting and release response coordination.  It consists of notification of the public agency assigned responsibility for First Response to hazardous materials release emergencies.  First Responders have participated with El Dorado Irrigation District personnel in response drills. 
 
PLANNED CHANGES TO IMPROVE SA 
FETY 
 
All of the improvements and mitigation measures identified in the process hazard analysis which El Dorado Irrigation District committed to accomplish have been completed or are in progress.  It is planned to improve the storage area by moving cylinders to an area which is protected better from weather, and to install a leak detector.  Any other measures identified by employees during workplace hazard surveys, or as a result of audit activities, will be thoroughly reviewed and considered for implementation.
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