Newport Wastewater Treatment Facility - Executive Summary |
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The Newport City Wastewater Treatment Facility currently receives and treats wastewater from approximately 5,400 City residents, the village of Derby Center and industrial wastewater. The facility has a design capacity of 1.2 MGD, and discharges secondary, treated, disinfected wastewater to the Clyde River (NPDES VT0100200) after an activated sludge treatment process and gaseous chlorine disinfection. Sludges are anaerobically digested and land applied. Excess chlorine in the effluent is removed by the addition of sulfur dioxide gas. Chlorine is stored at the facility as liquefied and compressed gas and is injected into the water as gas. Neither the gas nor the liquid is explosive, combustible or flammable. Sulfur dioxide is stored at this facility as a liquified compressed gas. The compound is non-combustible, non-flammable and non-explosive, but reacts violently with alkalines. Approximately 30 pounds per day of chlorine gas is consumed. Both gases are metered through flow- proportioned measuring equipment and used year-round. Chlorine and sulfur dioxide arrive on-site in one-ton cylinders. The maximum inventory of chlorine and sulfur dioxide is two containers each. Both chlorine and sulfur dioxide are stored in the Control Building in the feed room. The chlorinator and sulfonator are located in the same room. The two in-service containers of chlorine and sulfur dioxide are mounted on scales. The other containers are stored on cradles with the valves covered by protective hoods. When one chlorine container is empty, an auto change-over valve will switch to the other container of gas. The City of Newport is currently implementing the transition to liquid sodium hypochlorite as a disinfecting agent. Anticipated completion date for the project is December 1999. A Hazardous Materials Emergency Plan has been formulated to identify the chemical hazards that pose a threat to the employees and property of the Newport City Wastewater Treatment Plant and the citizens and property of the surrounding community. The plan is designed to assist in the development of mitigation efforts, lessen the effects of a hazardous substance incident, coordinate response and necessary assistance during emergencies, and establish a recovery system in order to return the facility to its normal condition. During a chemical emergency at the facility, response is coordinated by the Facility Emergency Coordinator (FEC). The FEC identifies the character, exact source, amount and extent of any released material. |