Village Creek Wastewater Treatment Plant - Executive Summary |
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EXECUTIVE SUMMARY The VILLAGE CREEK WASTEWATER TREATMENT PLANT (VCWWTP) is owned and operated by the CITY OF FORT WORTH (CFW). To comply with the requirements in 40 CFR 68 Chemical Accident Prevention Provisions, the CITY OF FORT WORTH WATER DEPARTMENT (CFWWD) developed a Risk Management Program (RMProgram) for the VCWWTP including Management System, Hazard Assessment, Accidental Release Prevention Program, and Emergency Response Plan. The RMProgram main goal is to reduce the employee and public risk of injury, death or damage from accidental release of chemicals. 1 MANAGEMENT SYSTEM The CFW has the overall responsibility for implementing and integrating the ARPProgram into their organization. In accordance with the Management System, the CFWWD Director is designated as the RMProgram Director, and the Assistant Water Director in charge of Production is the RMProgram Manager. Other qualified individuals are assigned responsibility for implementing each i ndividual requirement set forth in the Accidental Release Prevention Program and/or Emergency Response Plan. The RMProgram participants include the following positions: A. RMProgram Director B. RMProgram Assistant Director C. RMProgram Manager D. Hazard Assessment/Offsite Consequence Analysis Update Officer E. Safety Information Officer F. Hazard Review Update Officer G. Operations Manager H. Training Supervisor I. Maintenance Supervisor J. Compliance Audit Officer K. Incident Investigation Officer L. Emergency Planning and Response-Operations Officer M. Emergency Planning and Response-Safety Officer N. RMPlan Update Officer Management system detailed descriptions and procedures are provide in the Accidental Release Prevention Program to ensure every participant playing a role in the RMProgram understands their responsibilities. 2 REGULATED CHEMICALS AND PROCESSES Regulated toxic chemicals and processes at the VCWWTP are: A. Storage, transfer and use of chlorine in the chlorination system B. Storage, transfer and use of sulfur dioxide in dechlorination system Chlorine gas is stored as pressurized liquid in three (3) side-by-side tanks located outdoors. Maximum liquid chlorine inventory in each tank is 44,000 lbs. The maximum process quantity is 132,000 lbs., ignoring negligible quantities in the piping. Sulfur Dioxide gas is stored as a pressurized liquid in two (2) side- by-side tanks located outdoors. Maximum liquid chlorine inventory in each tank is 44,000 lbs. The maximum process quantity is 88,000 lbs., ignoring negligible quantities in the piping. 3 HAZARD ASSESSMENT The Hazard Assessment has been completed for the VCWWTP. Offsite consequence analysis modeling was performed based on the following principle elements: A. Meteorological parameters for the dispersion modeling analysis were determined using National Weather Service data collected at the Dallas/Fort Worth International Airport. Highest daily maximum temperature and average relative humidity over the last three-year period were used for worst-case scenarios. Typical meteorological conditions based on the data over the last three-year period were used for alternative release scenarios. B. Total quantity in the single largest tank was used for chlorine and sulfur dioxide worst-case scenarios. A leak from a liquid line near the outdoor storage tank was assumed for either chlorine or sulfur dioxide alternative release scenario. C. No mitigation measure was considered in worst-case scenarios. The excess flow valve, however, was considered for either chlorine or sulfur dioxide alternative release scenario. D. Distances to toxic endpoints for chlorine and sulfur dioxide worst-case scenarios were modeled using a dense gas dispersion model, DEGADIS. E. Distance to the toxic endpoint for the chlorine and sulfur dioxide alternative scenarios we re modeled using a dense gas dispersion model, ALOHA. F. Distance to the flammable endpoint for methane scenario was determined using a TNT-equivalent model. G. Offsite impact was evaluated with LANDVIEW III for each release scenario. The accidental release of sulfur dioxide from a storage tank is considered the worst-case scenario. A distance of 5.3 miles between the release source and the toxic endpoint was modeled in the offsite consequence analysis. The alternative scenario impact distance is 1.3 miles for sulfur dioxide and 1.2 miles for chlorine. For the worst-case scenario, LANDVIEW III estimated a population of 220,000 persons within the worst-case scenario impact radius of 5.3 miles. Populations are 5,400 and 3,300 persons for sulfur dioxide and chlorine alternative release scenarios, respectively. Public receptors within the worst-case scenario impact area include schools, residences, hospitals, correctional facilities, recreation areas and commercia l, office, or industrial areas. Public receptors within the alternate release scenario impact area are schools, residences, recreation areas and commercial, office, or industrial areas. No environmental receptors are within the impact area of the worst-case scenario. 4 ACCIDENTAL RELEASE PREVENTION PROGRAM A comprehensive Accidental Release Prevention Program Manual was developed. The main purpose of the manual is to provide operation and maintenance personnel detailed standard procedures to reduce employee and public risk to injury, death or property damage from accidental chemical releases. The manual includes the following elements and complies with requirements set forth in 40 CFR 68 Chemical Accident Prevention Provisions. A. Management B. Safety Information C. Hazard Review D. Operating Procedures E. Training F. Maintenance G. Compliance Audits H. Incident Investigation Detailed procedures for the Accidental Release Prevention Program were developed and are undergoing implementation and integration into routine operation and maintenance practices at the VCWWTP. Historical and future significant efforts focus on the following areas: A. Development of a safety information database essential for the successful implementation of other procedures, including operation, maintenance, training, compliance audits, incident investigation, and emergency planning and response. B. Implementation of corrective actions recommended during the most recent hazard review completed on April 22, 1999. This effort is one of the most important steps for preventing a chemical release or minimize its effects on plant personnel or the public. C. Regular review and revision of operating procedures to address the safely operating procedures for regulated process systems, including all eight (8) elements set forth in the regulation. When combined with the operator training program, current operating pro cedures are essential in ensuring safe operation of systems and preventing accidental releases. D. Regular review and revision of training programs to ensure plant personnel working on or near regulated processes are adequately trained and understand both inherent process hazards and appropriate response actions to accidental chemical releases. Employees who have received adequate classroom and/or on-the-job training and are currently qualified to safely operate the regulated systems have received certifications in writing by the RMProgram Manager. A special training session will be provided to plant personnel working on or near regulated processes as soon as final revisions to operating procedures are completed. E. Regular review and revision of the maintenance program to ensure that current, accurate, and complete procedures are provided for process equipment in regulated processes. Efforts were and are conti nuously made for the preventative maintenance of equipment per manufacturer's recommendations. Effective maintenance procedures are integral to preventing chemical releases that may result from mechanical failure of improperly maintained equipment. 5 THE FIVE-YEAR ACCIDENT HISTORY No accidental releases of regulated chemicals from a regulated process at the VCWWTP has occurred in the past five years resulting in any death, injury, or property damage on site, or known offsite impacts (i.e., deaths, injuries, evacuations, sheltering-in-place, or property damages, or environmental damages). 6 EMERGENCY RESPONSE PLAN CFWWD personnel do not respond to uncontrolled releases of chemicals from any regulated process at the VCWWTP. Plant employees are limited to responding only to incidental releases covered by maintenance procedures. Appropriate procedures have been developed and are in place that provide clear instructions on 1) how to determine if a leak is co nsidered an incidental release, and 2) how to notify local emergency responders in the event of an uncontrolled release. Current procedures were reviewed and revised to meet regulatory requirements, such as emergency notification, evacuation, training, documentation, availability, etc., under 29 CFR 1910.38(a). Regulated processes at the VCWWTP are not included in the community emergency response plan developed under 42 U.S.C. 11003. The local emergency responder is the Emergency Management Office in association with the City of Fort Worth Fire Department. Adequate safety information regarding regulated processes has been provided to the Emergency Management Office who has developed and implemented specific emergency response plans, provided suitable training, and conducted necessary drills in emergency response for regulated chemical releases from regulated processes. Although it will not be the responsibility of the plant employees to evacuate offsite areas, addresses and teleph one numbers of major public receptors inside a one (1) mile radius are provided in the plan. The CFWWD will work closely with the Emergency Management Office and document coordination activities and communications. 7 ON-GOING AND UP-COMING SAFETY IMPROVEMENTS To improve the safety of regulated facilities at the VCWWTP, the following plant expansion, process modification and facility upgrade projects are under construction or are scheduled to begin soon: A. Continuing revision and implementation of operational, maintenance, and training procedures. B. Inclusion of O&M manuals, equipment listings, plant drawings and other pertinent information on the Plant Intranet Site available to personnel with access to the Village Creek server. |