Standish Water Treatment Facility - Executive Summary |
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Risk Management Plan Executive Summary Portland Water District Water Treatment Plant Standish, Maine I. Executive Summary A. Accidental Release Prevention and Emergency Response Policies Portland Water District (PWD) is committed to operating its water treatment plant in Standish, Maine in an environmentally responsible manner and to providing a safe work place for its employees and the surrounding community. As part of this commitment to environmental stewardship and worker safety, PWD has developed and implemented numerous environmental and safety programs that are designed to eliminate and/or drastically reduce the potential for accidental releases. PWD has also developed and implemented a number of programs that are designed to ensure that if an accidental release occurs, it will be handled in a manner that minimizes adverse impact to people, the environment and the plant. Many of these programs have been in place for some time. PWD views accident prevention, and personne l and environmental protection as a continuous process. Consequently, PWD continuously strives to improve its accident prevention, environmental protection and emergency response programs. A recent addition to PWDs overall accident prevention and response program is the development of its Risk Management Program. PWDs Risk Management Program (RMP) complies with the U.S. Environmental Protection Agencys ("EPAs") Chemical Accident Prevention rule found at 40 C.F.R. Part 68. One of the requirements of this rule is to submit a Risk Management Plan. This document is PWDs RMP plan and provides the public with information about PWDs processes, accident prevention programs and emergency response planning efforts. PWDs compliance with EPAs RMP rule includes: 1. Completion of a hazard assessment in compliance with 40 C.F.R. Part 68, Subpart B, including the five-year accidental release history--PWD has never experienced an RMP reportable release or accident at its Standish Wate r Treatment Plant. 2. Implementation of a accident prevention program. The plants RMP accident prevention program is coordinated with the plants Process Safety Management (PSM) program which was developed under similar rules administered by the Occupational Safety and Health Administration "OSHA"; 3. Implementation of an emergency response program. As recommended in the RMP rule and by numerous federal response entities, the plant has developed a single response plan that is designed to meet the emergency response planning requirements applicable to the plant, under a number of applicable state and federal emergency response planning laws. Additional information regarding how PWD addresses each of these requirements is provided below and in the attached RMP plan. While the RMP program at PWD helps ensure that the facility is maintained and operated in a safe and environmentally responsible manner, it is just one component of PWDs comprehensive safety and environmental programs. Additional components that are beyond the scope of the RMP include, but are not limited to: regular employee/contractor safety training, periodic table-top safety and emergency response drills, acquisition and maintenance of emergency response and personnel protective equipment, development of safe work practices (confined space, lockout/tagout, hot work), implementation of safe work procedures, new project safety review procedures, preventive maintenance and regular inspections of all tanks and equipment that contain hazardous chemicals, chemical control and purchasing procedures, medical emergency response training, contractor certification, etc. The plant and all equipment is designed and operated to minimize the possibility of an accidental release. At a minimum, the plant and equipment meet government and industry design and construction standards. B. RMP Covered Stationary Source and Regulated Substance PWD owns and operates the Standish Water Treatment Facility in Standi sh, Maine. The plant treats potable water from Sebago Lake and distributes it to cities in the greater Portland area. The only chemical present at the plant in sufficient quantities to be regulated by the chemical accident prevention rule is chlorine. Chlorine is used to disinfect water as it is pumped from Sebago Lake. Chlorine is stored in 2,000 lb. tanks within the chlorinator room. The chlorinator room is equipped with chlorine detectors which sound an alarm in the event of an accidental release of chlorine. The total maximum amount of chlorine stored on-site is 16,000 lbs. (8 tanks). The maximum amount of chlorine used at any one time in the chlorination process is 8,000 lbs. C. Off-site Consequence Analysis As required by the RMP rule, PWDs off-site consequence analysis included evaluation of a worst-case accidental release for all toxic chemicals and an alternative release for each covered chemical. A worst-case release is defined by EPA as "a release of the largest q uantity of a regulated substance from a vessel or process line failure that results in the greatest distance to an endpoint defined in ' 68.22." 40 C.F.R. ' 68.3. EPA requires the worst-case accidental release to be modeled using highly conservative meteorological data designed to result in the maximum possible adverse impact. For example, EPA requires worst-case models to be based on the hottest day of the year, occurring at night with a very slow, steady wind which would not disperse a release very effectively. Further, the model assumes that the entire contents of the largest vessel is released instantaneously. According to the Chlorine Institute, no 2,000 lb. chlorine tank has ever released it contents in ten minutes. Accordingly, the probability of a 2,000 lb. cylinder of chlorine instantaneously releasing its contents in Maine on a 960F night when the wind is blowing at 3.4 miles per hour is extremely low. Using the EPA mandated criteria described above, the worst-case rel ease at the plant (for purposes of RMP) would involve a complete failure of a 2,000 lb. chlorine tank, filled to maximum capacity. If such a release occurred, it would result in a vapor cloud that could impact persons outside of the plants property line. PWD developed an alternative release of chlorine that focuses on more realistic release scenarios occurring during more common meteorological conditions. However, EPA requires modelling of a release which could impact off-site locations. After considering all criteria in the RMP rule, the Process Hazard Analysis performed on the chlorination process and all past releases, PWD has chosen an alternative release scenario that involves a whip failure on the gas side. In the valve whip failure scenario, the emission rate of chlorine gas was calculated to be 0.384 lbs./min, based on the maximum release rate published by the Chlorine Institute of 8 lbs/day/degree F. The chlorine gas would be vented from the chlorinator room to the outs ide by exhaust fans and then migrate based on meteorological conditions. PWD has never had a whip assembly failure at its Standish Water Treatment Facility in the past, however, based on discussions with PWD personnel, this scenario was chosen as the most likely to occur. D. Accident Release Prevention Program PWD has developed an accidental release prevention program that is designed and implemented to drastically reduce the possibility of an accidental catastrophic release. The program complies with the requirements of OSHAs Process Safety Management rule found at 29 C.F.R. Part 1910.119 and is analagous to RMP requirements found at 40 C.F.R. Part 68, Subpart D. The program has been very successful as evidenced by the fact that the plant has never experienced an accidental release that requires reporting under EPAs RMP rule. See 40 C.F.R. ' 68.42. To comply with the RMP rule, the plant has taken its existing PSM program and incorporated an additional focusprotection of the public. The basic elements of PWDs prevention program are described below: 1. Employee Participation. PWD has developed and implements a written plan of action regarding employee participation in the safety and accident prevention process. The plan describes how employees are: (A) consulted and what input they will have in the development of process hazard analysis (PHA) and other PSM and RMP safety elements; and (B) given access to PSM and RMP information at the plant. 2. Process Safety Information. PWD has compiled written process safety information which helped identify the hazards posed by chlorine, handling of materials, management, storage activities and the chlorination process in general. The compilation of process safety information provided the foundation for understanding the hazards involved in the chlorination process and was crucial to the development of a complete and thorough process hazard analyses (discussed in subsection 3 immediately below). The r equired process safety information includes information pertaining to the hazardous chemicals (e.g. chlorine), the technology of the process, and the process equipment. 29 C.F.R. ' 1910.119(d). The type of information pertaining to the technology of the process includes: (1) simplified process flow diagrams; (2) process chemistry; (3) maximum intended inventory; (4) safe upper and lower limits for temperature, pressure, flow and composition; and (5) an evaluation of the consequences of deviations, including those affecting the safety and health of employees and the nearby public. The equipment information includes: (1) materials of construction; (2) piping and instrument diagrams (P&IDs); (3) electrical classification; (4) relief system design and design basis; (5) ventilation system design; (6) design codes and standards employed; and (7) material and energy balances for processes built after May 26, 1992. 3. Process Hazard Analyses. PWD performed its most recent process haza rd analysis (PHA) on the chlorination system in 1998. The PHA is a key component of the process safety management system and PWDs RMP accident prevention program. It provided a thorough, orderly, systematic approach for identifying, evaluating, and controlling hazards posed by the chlorination process. The PHA utilized the what-if/PHA methodology in accordance with 29 C.F.R. ' 1910.119(e) and 40 C.F.R. ' 68.67. The PHA addressed: (1) hazards of the process; (2) engineering and administrative controls applicable to the hazards and their interrelationships such as appropriate application of detection methodologies to provide early warning of releases (e.g., process monitoring and control instrumentation with alarms); (3) consequences of failure of engineering and administrative controls; (4) facility siting; (5) human factors (human error); and (6) a qualitative evaluation of a range of the possible safety and health effects of failure of controls on the employees in the work pla ce. 4. Operating Procedures. PWD has developed and continues to develop and implement written operating procedures that provide clear instructions for safely conducting activities involved in the chlorination process. These procedures are consistent with the process safety information described in subtask 2: PWD has also developed and implements safe work practices that provide for the control of hazards during operations. For example, PWD has programs that govern the following activities: lockout/tagout; confined space entry; opening process equipment or piping; and control over entrance into PSM and RMP covered portions of the plant by maintenance, contractor or other support personnel. 5. Training. PWD provides employees, contractors and visitors with training that focuses on the special safety and health hazards posed by the plant operations, RMP and PSM covered processes, emergency operations including shutdown, and safe work practices applicable to the employees job tas ks. PWD confirms that employees and contractors involved in operating a covered process have successfully completed the required training. PWD documents that covered employees and contractors have received and understood the required training. Documentation, at a minimum, includes the identity of the employee or contract employee, the date of training, and the means used to verify that the employee understood the training. 6. Contractors. As part of PWDs contractor selection process it obtains and evaluates information regarding contract employers safety performance and programs: (29 C.F.R. ' 1910.119(h). PWD also: A. Informs contract employers of the known potential fire, explosion, or toxic release hazards related to the contractors work and the process; B. Explains to contract employers the applicable provisions of the facilitys integrated contingency plan (discussed below); and C. Develops and implements safe work practices to control the entrance, presence and exit o f contract employers and contract employees in covered process areas. 7. Pre-startup Safety Review. PWD always confirms that prior to the introduction of highly hazardous chemicals to a new or existing RMP/PSM covered process, the process is constructed and the equipment is designed in accordance with specifications; and that appropriate safety, operating, maintenance, and emergency procedures are in place to adequately protect the health and safety of employees and the nearby public. 8. Mechanical Integrity. PWD is developing written procedures to maintain the ongoing integrity of the process equipment listed below. PWD will train employees on the written procedures that ensure that the following process equipment is maintained: A. Pressure vessels and storage tanks; B. Piping systems (including piping components such as valves); C. Relief and vent systems and devices; D. Emergency shutdown systems; E. Controls (including monitoring devices and sensors, alarms, and interlock s); and F. Pumps. 9. Hot Work Permit. PWD implements a hot work permit program for all hot work operations (e.g., welding, soldering) conducted on or near any of the components involved in the chlorination process. 10. Management of Change. PWD has established and implements written procedures to manage changes to process chemicals, technology, equipment, and procedures associated with the chlorination process; and, changes to facilities that affect the chlorination process. These procedures ensure that the following considerations are addressed prior to any change: A. The technical basis for the proposed change; B. Impact of change on safety and health; C. Modifications to operating procedures; D. Necessary time period for the change; and E. Authorization requirements for the proposed change. 11. Incident Investigation. PWD investigates each incident which resulted in, or could reasonably have resulted in, a catastrophic release of a highly hazardous chemical in the workplac e. An incident investigation team is established and consists of at least one person knowledgeable in the process involved, including a contract employee if the incident involved work of the contractor, and other persons with appropriate knowledge and experience to thoroughly investigate and analyze the incident. 12. Emergency Planning and Response. PWD has developed an integrated contingency plan that satisfies all applicable state and federal emergency response and prevention planning requirements (described under emergency response policies below). 13. Compliance Audits. PWD will evaluate the water treatment plants compliance with the PSM Standard and the RMP rule at least every three years to verify that the procedures and practices it has developed are adequate and being followed. A report of the RMP and PSM audit findings will be developed. 14. Trade Secrets. PWD makes all necessary information available to those persons responsible for compiling process safety inform ation and those assisting in the development of the process hazard analysis. E. Five Year Accident History The Standish plant has never experienced a release that requires reporting under the chemical accident prevention rule. F. Emergency Response Procedures and Policies PWDs water treatment plant employees have been trained to control "non-emergency" incidents such as small, incidental spills and leaks. Employees have been trained on confined space entry procedures and the proper use of personal protection equipment (PPE). In the event of small fires, all plant employees are trained in the use of fire extinguishers. Personnel have also been trained to notify the plant manager in the event of more extensive accidental releases. The plant manager is responsible for assessment of the extent of the release, internal notification of the release and determination of whether or not outside responders are needed. During an emergency, all PWD employees have been trained to evacuate to a predesignated muster point to assist outside response teams. In the event that an accidental release occurs that is beyond the capabilities of PWDs employees to control, the plant depends on the the Standish Fire and Police Departments, and the Standish rescue squad for outside support. The Standish Fire Department operates under mutual aid agreements with the towns of Gorham, Buxton, Sebago, Limington, and Sebago to ensure that additional emergency response personnel and equipment are available to respond to an emergency release at the plant. In addition, PWD has an agreement with an outside contractor, Clean Harbors Inc., to provide emergency response services, if needed. PWD has also adopted and implements an Integrated Contingency Plan that meets the regulatory requirements of the following federal and state response planning and prevention laws: 7 OSHA Emergency Response Plan (29 C.F.R. 1910.120(q)) 7 OSHA Process Safety Management emergency response requirements (29 C.F.R. ' 1910.119(n)) 7 OSHA Hazard Communication Plan (29 C.F.R. ' 1910.1200(h)) 7 EPA Risk Management Plan Emergency Response Program (40 C.F.R. ' 68.95) 7 EPA Hazardous Waste Contingency Plan (851 DEP Regs. ' 8(B)(5) incorporating by reference 40 C.F.R. ' 264.51-.56) 7 EPA Oil Spill Prevention Control and Countermeasure Plan (40 C.F.R. ' 112.7) 7 EPA Best Management Practices Plan (40 C.F.R. ' 112.104(b)) 7 Maine Emergency Response Plan (37-B M.R.S.A. ' 795) 7 Maine Hazardous Matter Spill Prevention Control and Cleanup Plan (38 M.R.S.A. ' 1318-C). The ICP includes, among other things: 7 Procedures for notifying the public and the local emergency planning committee 7 Arrangements for first-aid procedures and emergency medical treatment procedures for exposure to chlorine 7 Emergency response and incident termination procedures 7 Procedures for using, inspecting and testing emergency response equipment 7 Employee training procedures 7 Procedures to amend the ICP plan G. Plan ned Changes The Standish Water Treatment Facility plans to equip chlorine tanks with vacuum detection devices that automatically close off the tank and stop releases of gas from the chlorination system in the event of leak. |