Streetsboro-Hudson WWTP - Executive Summary |
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Portage County Water Resources Risk Management Plan - Executive Summary Streetsboro-Hudson Regional Wastewater Treatment Facility Introduction In accordance with the U.S. Environmental Protection Agency (EPA) Risk Management Plan (RMP) regulations, the Portage County Water Resources Department (PCWR) has developed an RMP for this facility. This RMP is designed to provide a plan to follow in the event of an accidental release of chlorine gas, which is used as a disinfectant for the treated wastewater prior to discharge into Tinker's Creek, and to mitigate the impacts of a release, to both the public and local environment. The Streetsboro-Hudson Regional Wastewater Treatment Facility (Streetsboro WWTP) is a publicly owned and operated treatment works (POTW) located in Streetsboro, Ohio. This POTW serves a population of approximately 15,100, according to 1990 census data. Wastewater is collected from about a twenty five square mile area and is treated using advanced wastewater treatm ent processes and discharged into Tinker's Creek, a tributary to the Cuyahoga River. Chlorine disinfection is utilized as the final step in the treatment process and is stored, on site, in one ton cylinders. There are never more than two full containers on the site at one time. Chlorine is added to the wastewater and subsequently chemically removed, prior to discharge to the receiving stream. This RMP addresses the potential for an accidental release of the entire contents of gaseous chlorine from a full cylinder, as a worst case and, as the alternative scenario, a leak from a partially full container. Hazard Assessment In the fourteen years the plant has been in operation, no releases of chlorine have been recorded. However, in the event of a catastrophic failure of a full cylinder, the impacts to the public could be devastating. This facility is currently being surrounded by new industrial and commercial development, as has happened to most POTW's. When this facility was bui lt, it was remote from any major population centers and commercial developments. Since the beginning of this decade, development in the service area has been concentrated within a one mile radius of the Streetsboro WWTP. As a result, the potential impacts of a chlorine release have been magnified, especially to humans. Within the approximately twenty one square mile Distance to Toxic Endpoints (DTEP) zone, as defined in the Worst Case Scenario, are public and private schools, city emergency response organizations (police and fire departments), the majority of the City of Streetsboro residents, three industrial parks, approximately twelve linear miles of the Ohio Turnpike, portions of Interstate Route 480, and twelve linear miles of the Norfolk and Western railway. Also within the worst case DTEP area are several public recreation areas and environmentally sensitive areas such as: Tinker's Creek; Tinker's Creek State Park; and Hudson Springs lake and park. In the Alternate Release Scenario, a nearly one square mile area could be involved. However, no schools, residential housing, public recreation areas, or emergency response agencies would be affected. Although, as stated earlier, some newly developed commercial and industrial parks, hotels and restaurants are located within this zone of influence and might have to be evacuated. The chlorine cylinders and feed equipment are contained within a brick building, on the plant site, in separate rooms, each having only one door to the outside. At the present time, this is the only passive mitigation that is being employed. There is no active mitigation equipment (such as scrubbers, sprinklers, automatic shut-off valves, etc.) in place, nor is there any planned. Since the use of gas chlorine has the potential to impact a large population and sensitive environmental receptors, the PCWR department has made the decision to eliminate the use of gaseous chlorine for disinfection of the wastewater. Replacement of the gaseous feed equipment with the installation of a liquid feed system for sodium hypochlorite (liquid chlorine) for disinfection and sodium bisulfite for dechlorination of the effluent, is included in the plant expansion project, now in progress. This equipment should be on line by the summer of 2000. Prevention Program A. Program Management Under this program, the Wastewater Division Manager has primary responsibility for the RMP development and implementation, while the wastewater plant superintendent is the alternate program manager. B. Training Safety training, is of course, one the most important aspects of the program. Unless the supervisors and operators understand and follow the standard operating procedures and safety regulations, the risks of accidental releases are great. It is imperative, therefore, that the employees be sufficiently trained on the operation, maintenance, and safe handling of this material. Each employee has been issued a safety manual and is required to attend training on chlorine safety, respirator use, and personal protective equipment use, as well as other pertinent safety and operations training programs. Standard operating procedures (SOP's) have been written using clear, concise language which enable the operator to understand the steps required when changing cylinders, working on the feed system, calibrating analyzers, or performing other routine tasks on the chlorination system. This information is kept at the plant site, in the operation and maintenance manual, as well as the emergency response plans, and now within this RMP. Training is performed using several different methods. Each operator, at the wastewater plant, has been certified by the State of Ohio EPA in wastewater treatment. As part of this certification program, each receives extensive training on chlorine safety and general SOP's for gas chlorination feed systems. In addition to this training, on-the-job training is provided by the PCWR supervisory per sonnel and senior operators specific to the equipment and processes used at the plant. Training is done both when the employee is oriented after being hired, and each year before start-up of the system. C. Maintenance Proper maintenance of the chlorine feed equipment is critical to the integrity of the system. Each operator is trained and responsible for daily inspection of the equipment. When problems are identified, written SOP's are in place and used to shut down the system and complete the necessary repairs. Prior to start-up of the system each spring, the equipment is inspected and rebuilt, replaced or repaired as needed. This work is completed prior to the last week of April. During the last week in April, the system is put on line and started and final adjustments are performed on the equipment, before the Ohio EPA "summer" disinfection requirements become effective. Maintenance on the equipment, during the season, is documented and kept on file at the wastewater treatme nt plant. D. Compliance Audit As mentioned above, the goal of the PCWR is to eliminate the use of gas chlorine within the next three years. Therefore, a subsequent compliance audit, for gaseous chlorine processes, will not be performed. However, a program will be designed to evaluate the liquid system, to maintain the reliability and integrity of the system performance. E. Incident Investigation The PCWR has in place an accident/incident investigation policy and procedure. Each incident is investigated and documented, on the standard County accident form provided to each employee. All of the necessary information is included on this form: date of the incident; date of the investigation; description of the incident; contributing factors; recommended actions; personal or property injury/damage; and name and addresses of witnesses. Emergency Response Plan A written Emergency Response Plan (ERP) is available at each site operated by the PCWR that utilizes gaseous chlorine. Each ERP contains the SOP's for responding to a chlorine release, as well as other types of accidents, spills, and natural disasters. Fortunately, since the PCWR is a County organization, it is closely associated with the Local Emergency Planning Committee (LEPC), County Emergency Management Agency (EMA), and several local fire departments. As a result, the LEPC and EMA are aware of, and have provided the County's Hazardous Materials Response Team (HAZMAT) with emergency response training at PCWR sites. All PCWR operators have been trained in the SOP's for responding to a chlorine leak. Cylinder repair kits are available at each facility in the event of a leak, as is all the proper personnel protective equipment needed to enter the chlorine storage and feed rooms and to provide emergency evacuation of operating personnel. PCWR personnel have the responsibility of evaluating the severity of a gas leak and either initiating repairs or evacuating the plant site and calling for assistance fro m the County HAZMAT team. Emergency phone numbers and chain of command phone lists are maintained at the plant and are posted next to the telephone. In the event of a leak, that will affect areas outside of the plant property, the operator will call the emergency response phone number (911) and describe the existing conditions. Subsequently, PCWR supervisory personnel will be called (if not already on site), as will the Portage County Emergency Management Agency (EMA) director. Once the HAZMAT team is on-site, the local Fire Chief is given control of the site. PCWR personnel will remain on-site to assist in coordination of the leak repair and clean up efforts. In the event more than ten pounds of chlorine is released, and in addition to contacting the HAZMAT team, PCWR supervisory personnel will contact the LEPC and the Ohio EPA. The LEPC will then contact the State Emergency Response Commission and the National Response Center. Public Education and Communication This RMP will be made available and part of the County's LEPC program. In addition, the local police and fire departments will be given copies for their own use and information purposes. |