Ralph D. Bollman Water Treatment Plant - Executive Summary |
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Introduction The Contra Costa Water District's (CCWD) Ralph D. Bollman Water Treatment Plant (Bollman WTP) was constructed in 1968 and is located in Concord, California, adjacent to Mallard Reservoir. The Bollman WTP supplies filtered and disinfected water to the general public for drinking and other uses. Disinfection is necessary to destroy bacteria, viruses and other pathogens that may harm public health. The disinfection process has been recently converted from liquid chlorine under pressure (chlorine) addition to addition of liquid sodium hypochlorite (a higher strength version of household bleach). However, the chlorine system is being maintained as a backup disinfection system through the end of 1999 per the recommendation of the California Department of Health Services. Other chemicals are handled and safely used onsite to aid filtering and removal of organics and other particulate materials that may affect the taste and odor of the treated water. Chlorine is the only chem ical used at the Bollman WTP that is subject to two new regulations - the Federal Risk Management Plan (RMP) and the California Accidental Release Prevention Program (CalARP), which is California's version of the RMP. The compliance deadline for both of these regulations is June 21, 1999. The Bollman WTP has already implemented programs to comply with several other accidental release prevention regulations, including California's OSHA Process Safety Management (PSM) program and California's Risk Management and Prevention Program (RMPP), because of use and storage of chlorine. The California RMPP law was repealed in January 1997 and replaced by the CalARP regulation. The goal of these regulations and programs (new and existing) is to prevent and minimize the consequences of accidental releases of chlorine to both on-site staff and the surrounding community. To meet this goal, CCWD has identified potential hazards, implemented comprehensive accident prevention programs, installed saf ety and release response equipment, and prepared for emergencies. The CCWD's approach to meet safety information and associated operating and maintenance procedures and documentation requirements for RMP/CalARP is to build upon the existing programs and regulatory compliance activities associated with the PSM and RMPP. Most of the compliance requirements, documentation, procedures, and safety programs to meet compliance with these new regulations were taken directly from PSM and RMPP documents or existing operating and maintenance procedures. Chlorine Safety Policy Chemicals are widely used in industry, in the home, and in the environment. They are transported on roads, water, and railways. We at the Bollman WTP use chlorine to disinfect our water. Storing large qualities of chlorine can be a hazard. We take our safety obligations in storing and using chlorine as seriously as we take providing treated water. This RMP describes what could happen if there were to be an accident, the steps we take every day to ensure a safely operating plant, and what we do in event of an emergency. Please feel free to contact David Omoto, CCWD Environmental Compliance Officer at (925) 688-8023 if you have any questions regarding this plan. Water Treatment Plant Chlorine Disinfection System The Bollman WTP supplies treated drinking water to its customers. Over the past few years, Bollman WTP has undergone several major facility modifications to improve safety and drinking water quality. More recently, these modifications include replacing the chlorine disinfection system with a liquid sodium hypochlorite disinfection system. The U.S. Environmental Protection Agency (EPA) and California Office of Environmental Health Hazard Assessment (OEHHA) both recognize that liquid sodium hypochlorite disinfection systems do not pose the risk that an accidental release would affect people or property offsite. As of this time, the liquid sodium hypochlorite disinfection system is functi onal and operating in a start-up mode. However, by recommendation of the California Department of Health Services (DHS), a reduced amount of chlorine is maintained onsite in a back-up mode until completion of the hypochlorite system start-up. When start-up of the new system is completed, which is anticipated by the end of 1999, chlorine will be removed from site. The chlorine back-up system consists of two 1-ton containers with a load cell and a 1,000-pound per day chlorinator. This system is in an enclosed room at the northeast corner of the control building. The 1-ton containers are secured by chains to the load cell. Although all piping is in place to begin gas feed under vacuum, the containers themselves are closed and secured, with the gas and liquid feed valves protected by the shipping/storage bonnet. In the event that the use of this system is necessary, the containers will be connected as required in the "Chlorine Response and Standard Operating Procedures". These procedur es are found in CCWD's Safety and Health Manual. All chlorine storage and use at the Bollman WTP is conducted inside a building. The building where the backup chlorine system is stored and used, if required, is equipped with chlorine sensors that alarm in the event of a chlorine leak. The Bollman WTP is operated and maintained 24-hours a day by highly trained and experienced staff who are experts in the safe handling of chlorine and are prepared to respond to any release situation. Plant access is controlled so that only authorized personnel are allowed to enter the chlorine building. Trained plant staff must accompany visitors. Potential for Releases with Offsite Consequences CCWD evaluated two scenarios that might lead to releases. The worst case scenario is specified by the EPA and consists of releasing the entire contents of one of the chlorine containers over a 10-minute period. This scenario is extremely unlikely, resulting only from catastrophic events such as an airplane cr ash. This scenario assumes that the incident occurs after the containers have been delivered and are in the chlorine storage building because containers are not stored outside the building. An EPA-developed air dispersion model called RMP*Comp was used to estimate the distance to a point at which the released chlorine gas would no longer present a significant public health impact. The calculated distance for the worst case scenario was 0.9 miles, based on indoor chlorine use and storage. This distance may be exaggerated because of the use of the conservative EPA model and very conservative weather conditions mandated by the regulations. In addition, this scenario is extremely unrealistic and does not take into account Bollman WTP's existing safety and prevention programs or alarm systems. A second, alternative release scenario was identified based on the process hazard analysis as the occurrence of 1/16th-inch leak in the flexible connector between the piping and the chlorine contain er. This scenario is less improbable than the worst-case release scenario. It takes into account that Bollman WTP's extensive safety and release prevention systems will help to mitigate the impacts of such a release. The alternative release scenario also assumes more realistic regional and seasonal meteorology. The RMP*Comp model indicated that the distance to a point at which the released chlorine gas would no longer a significant public health impact for this alternative release scenario is less than 0.1 mile. There are no residences or sensitive receptors within this distance to the Bollman chorine facility. CCWD has developed and implemented the systems in its RMP/PSM program to prevent such releases. Accidental Release Prevention CCWD is in compliance with Federal and State Process Safety Management (PSM) requirements. CCWD's accidental release prevention program is based on the following key elements: 7 Detailed management system and clear levels of responsibilities and team m ember roles; 7 Comprehensive safety process information that is readily available to staff, emergency responders, and contractors; 7 Comprehensive preventive maintenance program; 7 Completion of a process hazard analysis of equipment and procedures with operation and maintenance staff participation and review; 7 Use of state-of-the-art process and safety equipment; 7 Use of accurate and effective operating procedures, written with operations and maintenance staff participation; 7 High level of training of operators and maintenance staff; and 7 Implementation of an incident investigation, inspection, and auditing program using qualified staff. Process and Chemical Safety Information Comprehensive chemical data have been assembled to include regulatory reporting and action thresholds, health hazard, and chemical exposure limitations, as well as detailed physical properties of chlorine. Included are chlorine background information, material safety data sheets (MSDS), and chlorine reacti on chemistry. Chlorine process equipment safety information has also been compiled, including specifications for the chlorine process, maximum intended inventory; safe upper and lower temperatures; safe upper and lower pressures; and codes and standards used to design, build, and operate the processes. This information is on file at the facility and readily accessible and available to the Bollman WTP staff. We also have procedures in place to update safety information if there is a major change that makes existing information inaccurate. Process Hazard Analysis In 1997, a detailed process hazard analysis (PHA) was conducted by a team of process operating and maintenance experts and process design engineers. The PHA technique used was the "Hazard and Operability" (HAZOP) study, a rigorous approach acceptable to the EPA. The PHA was lead by a person knowledgeable in the HAZOP study technique. A list of actions to resolve significant hazard review findings was prepared and has been fu lly implemented. As part of the Cal ARP requirements and the RMP external events evaluation, a seismic walkthrough was also recently completed based on the 1997 UBC, and recommendations were provided to CCWD for evaluation and implementation. Process Safety Management Program Summary Bollman WTP's PSM program includes the programs summarized below that control the use and storage of chlorine and ensure the integrity of these systems. Operating Procedures CCWD maintains up-to-date, accurate, written operating procedures that give clear instructions for the chlorine process. CCWD ensures effective operating practices by combining them with operating and maintenance training programs. Standard operating procedures (SOPs) provide system descriptions, specifications, equipment inspection requirements, and operating procedures for the chlorine system. Procedures include startup, shutdown, and normal, alternate, and emergency operation. Also included are maintenance and troubleshoot ing procedures, including consequences of deviation and the steps to avoid and correct deviations. CCWD will update procedures whenever a change occurs that alters the steps needed to operate safely. Operating procedures will be modified and in place prior to any new process equipment coming on line and before the process is started up after a change. Operations and Maintenance Training Program Each CCWD employee involved in operating or maintaining the chlorine process is trained in an overview of the process and detailed, applicable operating and maintenance procedures. CCWD's training program helps our employees understand the nature and causes of problems arising from operations involving chlorine on site, and increases the employees' awareness of process hazards. CCWD's training program includes both initial and refresher training that covers: 1) a general overview of the process; 2) the properties and hazards of the substances in the process; and 3) a detailed review of the p rocess operating procedures and safe work practices. Written tests, demonstrations, and field observation are used to verify that an employee understands the training material before the process work can be resumed. Training documentation includes: date of most recent review or revision to the training program; type of training required; and the type of competency testing used to ensure staff understand the training. Contractors CCWD has procedures and policies in place that ensure that only contractors with good safety programs are selected to perform work on and around the chlorine process. These policies and procedures also inform contractors of process hazards, access limitations to process areas, and emergency response procedures, and are provided to prepare the contractor to safely complete the work. CCWD sets minimum contractor safety performance requirements to work at the Bollman WTP, holds contractor safety briefings before allowing contractors near or in the chlorine process area, controls access to the chlorine process area, and evaluates contractor performance. Pre-Startup Safety Review and Mechanical Integrity Program CCWD ensures that a pre-startup safety review is completed for any new process at the plant which is covered by the PSM or RMP rules, or for significant modifications to an existing covered process that requires a change in the process safety information. CCWD maintains the mechanical integrity of process equipment to help prevent equipment failures that could endanger workers, the public, or the environment. CCWD believes that this program is the primary line of defense against a release. The mechanical integrity program addresses equipment testing and inspection, preventive maintenance schedules, and personnel training, including: 7 Written procedures for maintaining mechanical integrity through inspection and testing of process equipment, based on instructions of equipment vendors, industry codes, and prior operating experien ce 7 Written procedures for performing inspections and tests on process equipment at specified intervals 7 Training of maintenance personnel in procedures for safe work practices such as lockout/tagout, line or equipment opening, and avoidance and correction of unsafe conditions 7 Procedures specifying training requirements for contract maintenance employees, as well as requiring contractors to use plant developed maintenance procedures for process areas. Hot Work Permits and Management of Change CCWD requires employees and contractors to employ safe work practices when performing "hot work" in, on, or around the covered processes. CCWD uses a comprehensive permitting and training program to ensure hot work is performed safely. CCWD provides a system and approach to maintain and implement any management of changes or modifications to equipment, procedures, chemicals, and processing conditions. This system allows CCWD employees to identify and review safety hazards and gather add itional safety, process, or chemical information before any proposed change is implemented that would either compromise system safety or need training before implementation. Internal Compliance Audits Internal compliance audits are conducted at a minimum of every three years to verify compliance with the programs and procedures contained in the RMP. CCWD assembles an audit team of personnel knowledgeable in the Risk Management Program rule and in the process. This team evaluates whether the prevention program satisfies the requirements of the RMP rule and whether the prevention program is sufficient to help ensure safe operation of the process. The results of the audit are documented, recommendations are resolved, and appropriate enhancements to the prevention program are implemented. Incident Investigation CCWD investigates all incidents that could reasonably have resulted in a serious injury to personnel, the public, or the environment so that similar accidents can be prevented. CCWD trains employees to identify and report any incident that requires investigation. An investigation team is assembled and the investigation is initiated within 48 hours of the incident. The results of the investigation are documented, recommendations are resolved, and appropriate process enhancements are implemented. Information found during the investigation is reviewed by affected staff, added or used to revise operating and maintenance procedures, and incorporated into existing training programs, if warranted, to prevent future incidents. Five-Year Accident History No accidental releases of chlorine have occurred at the Bollman WTP that have resulted in deaths, injuries, or significant property damage on site, or known offsite deaths, injuries, evacuations, sheltering in place, property damage, or environmental damage. Any small, incidental releases are quickly handled or neutralized to prevent off-site impacts and safety or health problem for on-site workers and the com munity. Emergency Response Program CCWD has implemented its Emergency Response Program, as well as installed safety systems on its chlorine process to prevent and mitigate chlorine releases. The goal of the emergency response program is to protect its employees and the public in the unlikely event of a release. The two major elements of the emergency response program are an emergency action plan and notification procedures, both of which are described in CCWD's Emergency Response and Evacuation Plan/Employee Training. In the event of a release, the Operator/Supervisor on duty is responsible for immediately calling the on-duty Antioch Control Operator who in turn calls the local fire and emergency medical services agency. The Operator/Supervisor on duty uses the plant public address system to announce the plant evacuation. The local fire and emergency medial services agency is responsible for alerting the public regarding the release. Planned Changes to Improve Safety CCWD is in the process of converting the Bollman WTP water disinfection process from gaseous chlorine to the use of liquid sodium hypochlorite. Completion of this conversion is expected by the end of 1999. At that time, the potential for offsite consequences from a release of a Section 112(r) chemical will have been eliminated along with the requirement to maintain the RMP/PSM program. CCWD will continue to maintain its own safety programs for hazardous materials to protect its employees and the public. |