Kansas City, Missouri Water Treatment Plant - Executive Summary |
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Executive Summary Accidental Release Prevention and Emergency Response Policies The Kansas City, Missouri (KCMO) Water Treatment Plant (WTP) prevents accidental releases of chlorine and anhydrous ammonia by training and adhering to industrial and governmental codes and implementing good engineering practices. KCMO WTP's prevention program, safety information, hazard reviews, operating procedures, training, maintenance, compliance audits, and incident investigations are continuously updated. Every employee of the KCMO WTP remains aware of the potential for chlorine and anhydrous ammonia releases and disturbance of the systems. In an emergency, the KCMO WTP's first consideration is the safety of personnel and the community. The second consideration is the protection of property, equipment, and the facility. The KCMO WTP maintains emergency response procedures that allow KCMO WTP personnel to respond to releases when possible. The KCMO WTP relies on the Hazardous Materials (H azMat) Division of the Kansas City, Missouri Fire Department as well as Emergency Response Teams from private industries to assist in responding to emergency situations. All associates are trained to recognize releases of chlorine or anhydrous ammonia and to activate the alarms and emergency response procedures immediately. The KCMO WTP: Chlorine and Anhydrous Ammonia The KCMO WTP is located at 1 NW Briarcliff Road in Kansas City, Missouri. The plant uses chlorine and anhydrous ammonia to treat water. The KCMO WTP has the capacity to store 56,100 pounds of anhydrous ammonia in one process, and 12,000 pounds and 426,000 pounds of chlorine in two separate processes. Since these quantities exceed the Risk Management Plan (RMP) thresholds, these toxic substances must be addressed in the RMP. The KCMO WTP does not store or use any other toxics or flammables above threshold quantities that are regulated by the Environmental Protection Agency (EPA) through 40 Code of Federal Regulations (CFR) Part 68. Offsite Consequence Analysis Models and Guidance Regulation 40 CFR Part 68.25 allows for the use of publicly available techniques that account for the modeling conditions and are recognized by industry as applicable as part of current practices. RMP guidance documents were used which were created by EPA and made available through EPA's Chemical Emergency Preparedness and Prevention Office (CEPPO). Worst-Case Release Scenario For regulated toxic substances that are normally gas at ambient temperature, but stored as a liquid under pressure, EPA requires the worst-case release scenario to involve the release of the greatest amount of that substance held in a single vessel. The regulations require that the release occurs within a ten-minute time period and takes into account wind speed, atmospheric stability conditions, elevation of the release, gas density (either a dense or a buoyant gas), and the maximum daily temperature over the past three years. The analysis c onsidered a wind speed of 1.5 meters per second and F atmospheric stability. The release was considered to occur at ground level (0 feet) with urban topography surface roughness. To account for gas density in the dispersion analysis, chlorine was considered a dense gas, and anhydrous ammonia was considered a buoyant gas. A catastrophic scenario of the 90-ton chlorine railcar is a 180,000-pound release at a rate of 18,000 pounds per minute. The distance to the endpoint is 14 miles for a 90-ton railcar. The KCMO WTP maximum anhydrous ammonia inventory is 56,100 pounds, yielding a release rate of 5, 610 pounds per minute. Using a conservative release rate estimate of 6,000 pounds per minute, the distance to the endpoint is 2.8 miles for an urban area. Since 14 miles is much greater than the distance for anhydrous ammonia, chlorine is considered KCMO WTP's worst-case release scenario. Alternative Release Scenario Since alternative release scenarios are more likely to occur than th e worst-case scenarios, these scenarios are more suitable in emergency planning. Based on the past history of the plant and the recorded five-year accident history, this plant site has not had a release of chlorine that has migrated off the plant boundaries. Considering the active mitigation systems in place for chlorine, trained personnel, Standard Operating Procedures for handling chlorine, and over 70 years with no off-site release, the following alternate release scenario has been selected. A chlorine release in the Chlorine Building or the Filter Building was evaluated using EPA's RMP air model, RMP*Comp. This scenario includes a hose, piping, or a valve failure resulting in the release of gas through the 5/16-inch-diameter opening. The scrubber will actively mitigate up to 99.99% of the release. The remaining chlorine escapes from the building as a gas. This scenario assumes a 30-minute duration at a rate of 0.000711 pounds per minute to the atmosphere. Using RMP*Comp, t he estimated distance to the endpoint is 0.08 miles. EPA's electronic RMP filing software, RMP*Submit, does not allow a release rate less than 0.1 lbs/min; therefore, 0.1 lbs/min was reported in RMP*Submit. Additionally, RMP*Submit does not allow a release quantity less than 1 pound. Although the actual release quantity modeled was 0.0213 pounds, 1 pound was reported. Two alternative scenarios for anhydrous ammonia were evaluated. The first scenario, a gas piping or instrument connection failure, involves a small gas leak from gasket failures, small or large breaches in piping, or small instrument orifices. This scenario assumes a release from the top of the horizontal tank, and anhydrous ammonia escapes as a gas. For this scenario, a 60-minute duration and a hole diameter of 0.5 inches was assumed. In an urban setting, the distance to endpoint is 637 feet, or 0.12 miles. The second scenario involves failure of a tank excess flow check valve or pressure relief valve. This sc enario was modeled as a release from an orifice on the top of a horizontal tank, and the anhydrous ammonia escapes only as a gas. The size of the hole yields an initial release rate that can be used to simulate the rated flow of the excess flow valve. The duration of the release is estimated to be one hour. Again, a hole diameter of 0.5 inches was assumed, yielding a distance to endpoint of 0.12 miles. Accidental Release Prevention Program and Chemical-Specific Prevention Steps KCMO WTP's prevention program consists of safety information, hazard reviews, operating procedures (Standard Operating Procedures), training, maintenance, compliance audits, and incident investigations. To prevent releases, the KCMO WTP compiled chlorine and anhydrous ammonia safety information, including: Material Safety Data Sheets (MSDS); maximum intended inventory; safe upper and lower temperatures, pressures, and flows; equipment specifications; and codes and standards used to design, build, and opera te the chlorine and anhydrous ammonia systems. A hazard review was conducted for each regulated process. The hazard review team consisted of plant management, process operation and maintenance personnel, and consulting process design engineers. The team analyzed the hazards associated with the chlorine and anhydrous ammonia processes using the checklist and what-if techniques. The hazard review team documented recommendations and set a schedule for implementation. The KCMO WTP has adopted written Standard Operating Procedures (SOPs) that provide system descriptions, specifications, and operating procedures for the chlorine and anhydrous ammonia systems. The procedures address initial startup, normal operations, normal and emergency shutdown, inspections, temporary operation, restartup, and consequences of deviation. Additionally, MSDSs are included in the SOPs. The KCMO WTP has a training program with guidelines for conducting regular, structured plant training for associates, including operators and maintenance personnel. Records of the training program, including content of the course, course manual, examination, and record of attendance are maintained. Preventive maintenance, inspection, and equipment testing is performed to ensure safe operations at the KCMO WTP. The maintenance program includes a preventive maintenance schedule based on manufacturer's recommended instructions. The KCMO WTP and maintenance contractors continually assess the compliance status of the chlorine and anhydrous ammonia facilities through facility inspections and preventative maintenance. The compliance audit process will be performed at least once every three years to ensure that the RMP procedures and practices are adequate and being followed. To complete a compliance audit, the KCMO WTP must demonstrate that documentation, employees' knowledge (interviews), and the physical facility (through inspection) comply with 40 CFR Part 68. The RMP incident investigation pro gram outlines the RMP investigation process. If the chlorine or anhydrous ammonia incident is reportable, the employee completes an Incident Report form and submits it to the Safety Officer. The Safety Officer is responsible for making sure the Incident Report Forms are completed. An Incident Investigation Team investigates how the incident occurred and determines whether errors can be corrected by instituting general or specific safeguards for the process or whether it is necessary to institute additional training for the employees. The Five-Year Accident History Only two releases in the previous five-year accident history have resulted in an injury related to a regulated toxic substance. On September 17, 1998, a release of chlorinated water (less than one pound of chlorine) from a process vessel caused an injury to a contract worker. The actual release quantity was estimated to be 0.77 pounds. Since RMP*Submit does not accept release quantities less than one pound, one poun d was reported in the accident history. Mechanical equipment failure initiated the event, and human error contributed to the accident. While the contractor's improper presence in the affected area did not lead to the release, this action did lead to the injury. Off-site responders were notified. The KCMO WTP changed procedures, increased contractor safety, and emphasized adherence to proper procedures to reduce future accidents. This release did not go off site. Another release that resulted in an injury occurred on July 29, 1996. Equipment failure caused a release of approximately 33 pounds of chlorine. The gas release was from a process vessel. Off-site responders were notified. This incident did not instigate any changes to KCMO WTP processes or procedures. This release did not go off site. Emergency Response Program The KCMO WTP developed The One Plan, an Integrated Contingency Plan, as its emergency response program. In a chlorine or anhydrous ammonia release, T he One Plan provides associates direction and guidance to recognize a release, shutdown operations, and initiate emergency response operations. In an emergency, the Hazardous Materials (HazMat) Division of the Kansas City, Missouri Fire Department will be called immediately after notifying the Plant Manager, followed by the Local Emergency Planning Committee (LEPC), the Missouri Department of Natural Resources (DNR) Environmental Emergency Response Office, and the National Response Council. Current phone numbers and notification lists are posted throughout the KCMO WTP. Every employee of the KCMO WTP remains aware of the potential for chlorine and anhydrous ammonia releases and disturbance of the systems. The KCMO HazMat does annual training on site, and evacuation drills are conducted annually. In an emergency, The One Plan's first consideration is the safety of personnel and the community. The second consideration is the protection of property, equipment, and the facility. I n an actual or potential emergency, the area of the emergency will be secured, the Emergency Coordinator will be notified, and the source will be assessed for corrective measures. Evacuation procedures include sounding an alert via telephone, cellular phone, radio, or intercom system; gathering at assembly areas where roll call will be taken; shutting down designated equipment; and posting security personnel to isolate the area. The public will be contacted through the Fire Department or the KCMO HazMat. The Plant Manager will fill out the report form and submit it to the proper authorities. The One Plan includes emergency and first aid procedures, training requirements, and program review and update procedures. Planned Changes to Improve Safety To improve safety, the KCMO WTP made changes based on the Hazard Review conducted for the chlorine and anhydrous ammonia systems. The review prompted a list of recommendations that were implemented. The most significant change to improv e safety is the implementation of The One Plan in which all personnel are trained in the emergency response plan and take part in annual drills. Recommendations for the Filter Building chlorine system included improving documentation of maintenance and on-the-job training, replacing expansion devices, evaluating low pressure alarms, and tagging several valves. In 1999, the KCMO WTP completed construction of a new chlorine storage and feed facility equipped with a scrubber capable of scrubbing a 60,000 pound chlorine release. Recommendations for the Chlorine Building chlorine system involved changes to SOPs, including not allowing trucks to enter the facility without operator guidance, a maximum operating height for the hoist and chlorine lifting beam, quarterly replacement of ammonia test bottles, and checking the chlorinator indicator rate valve against the rotameter reading. Recommendations for the anhydrous ammonia system included tagging several valves, posting caution signs for truck loading/unloading, and labeling tank with "Anhydrous Ammonia". The review prompted the evaluation of excess flow and/or back pressure check valves located inside of the container or at a point outside as close as practicable to where the line enters the container, hydrostatic relief valves between each pair of valves in the liquid piping, a shower close to the tank, and back flow check or excess flow valves in the loading/unloading lines. Changes in Standard Operating Procedures include having an operator present at all times during truck delivery. |