Carrollton Water Purification Plant - Executive Summary |
Executive Summary This document was developed to comply with the Environmental Protection Agency's (EPA's) Risk Management Program II, under Section 112 (r) of the Clean Air Act (CAA) Amendments of 1990, 40 CFR Part 68. An outline of the Risk Management Program is provided in Figure ES-1. The disinfection process (i.e., chlorine system) is covered under this regulation at the Sewerage and Water Board of New Orleans (S&WB) Carrollton Water Purification Plant (WPP). To meet the regulation requirements, this binder contains useful information on the chlorine and ammonia systems. The technical information herein may be used as a training reference in initial and recurring operator and maintenance training. Training on process fundamentals, operations, and maintenance, coupled with the recommended process modifications discussed below, will reduce the potential hazards to plant personnel and the surrou nding community. An Emergency Response Program and an Incident Investigation Program are included. These two programs should be an integral part of both initial and recurring training. A Risk Management Plan (RMP), in the format required by the EPA, is included at the end of the main body of this document. It consists of a summary of data elements as required by EPA for inclusion in a public access database. The RMP is intended to inform the public of Carrollton WPP's proactive stance toward protection of the environment and the surrounding community. Hazard Assessment The Hazard Assessment is comprised of a Worst Case and Alternative Release Scenario for the chlorine system, as well as a 5-Year Accident History for the same. The Hazard Assessment was conducted as an initial screening procedure as part of determining which Program Level (I, II, or III) the Carrollton WPP falls. Residences lie within the EPA-defined endpoint concentrations of Carrollton's Worst-Case releases. Therefore, the plant is ineligible for Program I. The Carrollton Water Purification Plant is operated by public personnel and therefore excluded from Program III. Carrollton Water Purification Plant is included in Risk Management Program II. The Hazard Assessment is provided in Chapters 1 through 3. Worst Case Scenario The Worst Case Scenario (WCS) for the chlorine system is defined as a 55-ton railcar (110,000 pounds) of chlorine being released by a catastrophic event within a 10 minute duration. This scenario was developed and modeled using the EPA approved RMP Comp model. The toxic endpoint for chlorine was determined to be 9.9 miles by RMP Comp at the 3 ppm concentration specified by the EPA. It should be noted that at this concentration, a person may be exposed for up to one hour without suffering permanent injuries (ERPG-2). The WCS for the ammonia system (10,000 gallon tank - 80% full) is defined as 8,000 gallons (45,520 lbs ) of ammonia being released by a catastrophic event within a 10 minute duration. This scenario was developed and modeled using the EPA approved dense gas dispersion model SLAB. The toxic endpoint for ammonia was determined to be 0.83 miles by the SLAB model at the 200 ppm concentration specified by the EPA. It should be noted that at this concentration, a person may be exposed for up to one hour without suffering permanent injuries (ERPG-2). Alternative Release Scenario The Alternative Release Scenario (ARS) of chlorine was modeled using RMP Comp. An estimation of approximately 3983 pounds of chlorine gas released was derived from the scenario of a flexible connection failure. The toxic endpoint for the chlorine system ARS was determined to be 0.8 miles. The alternative release scenario of ammonia was also modeled using SLAB. An estimation of approximately 2700 pounds of ammonia released was derived from the scenario of an outdoors piping failure. The to xic endpoint for the ammonia system ARS was determined to be 0.17 miles. 5 Year Accident History One (1) qualifying chlorine accident has been documented within the past 5 years. In 1998 a minor release of chlorine occurred due to a check valve that cracked during rail car disconnection. The crack separated the valve from the rest of the piping and allowed chlorine to escape into the atmosphere. Four employees were exposed to chlorine gas during the release, however, all four were wearing protective equipment and escaped serious injury. There were no off-site consequences or impacts caused by this incident. Management Program The Management Program consists of the Document Management System described below: Document Management System A Document Management System was established to attribute responsibility for the development, implementation, and maintenance of the Risk Management Program. The Program must be updated every three years, or any time a co vered process undergoes a physical or administrative modification. The Document Management System is largely a function of the Risk Management Program Team, described below in Table ES-1. Risk Management Program Team Tables ES-1 lists the employees responsible for the Risk Management Program development, implementation, and maintenance. The Plant Superintendent has the ultimate responsibility. Prevention Program The Prevention Program is more appropriately entitled the Accidental Release Prevention Program. It is comprised of Safety Information, Hazard Review, Operating Procedures, Training, Maintenance, Incident Investigation, and Compliance Audit procedures. Each has an entire chapter devoted to it in this RMP, and is described in more detail below. Safety Information Safety Information is divided between Chemical Safety Information and Process Safety Information. Each is briefly described below. Chemical Safety Information Comprehensive chemical data is provided in this section to include; regulatory reporting action thresholds, health hazard and chemical exposure limitations, as well as physical properties of chlorine and ammonia. This information was compiled from numerous sources, and is intended to be a one-stop source for the reader seeking data on these compounds. The physical data will provide useful information in the inevitable event the plant process is modified, thereby requiring revisited dense gas dispersion modeling. It is also imperative that plant operators and managers are appraised of the potential health hazards and exposure limits associated with these chemicals. Process Safety Information Process Safety Information was meticulously compiled on each system studied. Basic specifications on each process are included in this document for easy reference. Details such as Maximum Intended Inventory, Safe Upper and Lower Temperatures, Safe Upper and Lower Pressures, and Codes and Sta ndards Used to Design, Build and Operate the Process are provided in this section. Used as a training reference, together with the Process Schematics, the reader will readily understand the function and operation of the plant chlorine and ammonia systems. Chlorine System Hazard Review A Hazard Review was also conducted for the chlorine system. The Hazard Review technique used was a hybrid Hazard and Operability Study (HAZOP), in the form of a "What If" analysis. The "What If" was developed from HAZOP experience at similar chlorine systems. The Hazard Review team consisted of plant management, process operating and maintenance experts, outside process design engineers, and consultants knowledgeable in the Hazard Review process itself. Recommendations The result of the Hazard Review is a set of recommendations for the plant to implement. Rule 40 CFR 68.50 requires the Sewerage & Water Board to ensure that problems identified are "resolved in a timely man ner." For those items that can not be promptly resolved, it is recommended that a schedule be developed that addresses those issues, with responsibility for each assigned to the appropriate personnel. Please note that these are not the recommendations of Camp Dresser & McKee, Inc. Rather, they are recommendations developed by the Hazard Review Team with a consensus from all team members. CDM's role was to facilitate the Hazard Review process. Recommendations are summarized below: ~ Conduct feasibility study of alternative disinfectants and/or installation of chlorine scrubbing/enclosure alternatives for both the rail car and 1-ton cylinder systems ~ Install additional chlorine detector north of evaporators ~ Move vacuum regulator (upstream) closer to evaporators ~ Install temperature switch interlock on evaporator bath to automatic supply shut-off ~ Install leak detector interlock to supply shut-off ~ Re-evaluate piping/valving a nd consider additional expansion tanks ~ Install chlorine gas/liquid filters ~ Construct sheltered area with monorail for one-ton container storage ~ Mount vacuum regulator check units directly on the ton containers ~ Install panel hardware on evaporator room doors ~ Install speaker system so that all employees may hear warning/emergency announcements. ~ Coordinate Emergency Response Procedures with New Orleans HAZMAT. Ammonia System Hazard Review The hazard review for the ammonia system was conducted as an EPA approved Facility Audit. The recommendations resulting from the audit include the following: ~ Properly label all liquid/vapor lines, ~ Conduct a feasibility study of enclosing/scrubbing the ammonia storage tank. Operating Procedures Basic chlorine and ammonia system operating procedures have been developed and documented for the Carrollton WPP. They provide system descriptions, specifications, and operating p rocedures for the chlorine gas system. Procedures include Start-up, Shutdown, Normal, Abnormal, and Emergency Operation. Also included are Troubleshooting Procedures. Training Training is required by the EPA to be included in the Risk Management Program. A program has been developed with guidelines on how to conduct regular and structured plant training. Training Record Forms are included with the Program for the required documentation. Additionally, a Training Record has been compiled and included for all affected personnel associated with the covered processes. ~ Install warning system for offices adjacent to ammonia tank. ~ Implement special emergency procedures for adjacent office area. ~ Coordinate Emergency Response Plan with New Orleans HAZMAT. Maintenance Basic maintenance procedures have been developed with associated documentation forms. Sound preventive maintenance will reduce potential hazards to personnel onsite, as well as to the off-site public. In the event of an inspection or compliance review, state and federal regulators will request to see documentation and record keeping associated with the Maintenance Program. Incident Investigation An Incident Investigation Program has also been developed. The EPA has established strict guidelines to follow in the aftermath of any release involving the chlorine or ammonia system. The Incident Investigation Program outlines key milestones that must be accomplished within 24 hours of any covered incident, and the actions that must occur subsequently. Ultimately, it is desired that the plant learns from the incident and takes action to prevent similar incidents in the future. Incident Investigation Report Forms are included, and must be maintained for a minimum of five years after each incident. Compliance Audits Internal Compliance Audits must be conducted every three years to verify compliance with the programs and procedures contained in this document. The Plant Manager must certify that the Risk Management Program team has evaluated compliance with the provisions of the Program, and verify that the procedures and practices are adequate and are being followed. Audit Report Forms are provided, the two most recent of which must always be maintained. This means that in the year 2006, the Compliance Audit Report for the year 2000 may be discarded. Emergency Response Program The Emergency Response Program is included as part of the Risk Management Program, in case a significant release ever occurs. As in all the above programs, it is important to review this program regularly. The Rule, 40 CFR 68.95 requires training for all employees "in relevant procedures" of the Emergency Response Program. It is recommended that training on the specific plant safety procedures take place upon initial employment and every year thereafter, as with most of the other RMP training programs. Other training re commendations, i.e., OSHA 8, 24, and 40 hour training are discussed in the Emergency Response Program as appropriate to the level of response. Risk Management Plan A copy of the Risk Management Plan (EPA Submittal) is provided. As stated previously, this document is public information. Following submission to the EPA, the information will be uploaded on a public-access database. No other portion of the Carrollton WPP Risk Management Program must be made available to the public. Summary of Action Items for the Carrollton Water Plant The RMP Rule, 40 CFR 68.42 requires that details of all accidental releases be recorded from this date forward. The format details are provided in Sections 2 and 10. The RMP Rule, 40 CFR 68.15 requires that the Document Management System (e.g., the RMP Team) be updated anytime personnel changes or administrative changes are made that would affect the lines of authority or responsibility for maintaining the RMP at the Carrollton Water Purification Plant. The format details are provided in Section 3. The RMP Rule, 40 CFR 68.54 requires that each employee presently operating a process, and each employee newly assigned to a covered process be trained or tested competent in the operating procedures. As an alternative, the S&WB may certify in writing that the employee has the required knowledge, skills, and abilities to safely carry out the duties and responsibilities as provided in the operating procedures. Training documentation forms are provided in Section 7. CDM facilitated the development of operating procedures for the Carrollton WPP, and they are provided in Section 6. These operating procedures may be used as training guides as well. The RMP Rule, 40 CFR 68.56 also requires training on the plant maintenance procedures. Maintenance guidance is provided in Section 7. The S&WB must train or cause to be trained each employee involved in maintaining the on-going mechanical integrity of the process. To ensure that the employee can perform the job tasks in a safe manner, each such employee must be trained in the hazards of the process, in how to avoid or correct unsafe conditions, and in the procedures applicable to the employee's job tasks. Refresher training on operating and maintenance procedures must be provided every three years. Training documentation forms are provided in Section 8. The RMP Rule, 40 CFR 68.60 requires incident investigations not later than 24 hours following each incident. That guidance is provided in Section 9. The RMP Rule, 40 CFR 68.58 requires the New Orleans S&WB to certify compliance with RMP Accident Prevention Program provisions at least every three years to verify that the procedures and practices developed under the rule are adequate and are being followed. That guidance, along with Compliance Audit forms, is provided in Section 10. The Rule, 40 CFR 68.95 requires training for all employees "in relevant p rocedures" of the Emergency Response Program. It is recommended that training on the specific plant procedures take place upon initial employment and every year thereafter, as with most of the other RMP training programs. Other training recommendations, i.e., OSHA 8, 24, and 40 hour training are discussed in the Emergency Response Program as appropriate to the level of response. The Emergency Response Program is discussed in Section 11. Training documentation forms are provided in Section 10. The S&WB must submit the Risk Management Plan (RMP) to the appropriate agency by June 21, 1999. The RMP is a summary of the Program, and is located in Section 12. The RMP will be submitted electronically using EPA's RMP Submit software. |