Comprehensive Environmental Inc. (CEI) worked with the Kingston Water Department, Kingston, MA to construct a new water treatment facility to remove manganese from the Trackle Pond Well. The water treatment facility has a design capacity of 1.5 mgd (expandable to 3 mgd) with a primary treatment process utilizing pressure filtration. The facility includes pumps, chemical feed systems (oxidation/disinfection and pH adjustment), pressure filtration system, residuals management, instrumentation, controls, and SCADA system. The facility is a 4,450 square foot slab-on-grade masonry superstructure with brick siding and salt box style roof.

The pressure filters and associated piping, valves and instrumentation are located in the main process area. Individual rooms are provided for storage of potassium hydroxide, sodium hypochlorite, electrical equipment and control equipment.  The facility is designed with the operators in mind, as such, all piping and equipment are located on one level and an overhead door is provided to facilitate efforts involved with installation of a fourth filter in the future. Provisions were made allowing for the addition of a clearwell and finished water pump facility should the need arise to meet the 4-log virus removal requirement of the Groundwater Rule.  CEI provided design, permitting, bid phase, construction phase administrative and startup services.

The Town is a state classified Green Community which works in harmony with CEI’s approach to projects. The facility was constructed with energy efficiency innovations including a 20 kW solar power system with panels located on the roof of the facility.

The pressure filtration equipment includes three 12 foot diameter vertical pressure vessels with space for a fourth to accommodate future expansion.  The system is designed as a pump-through process from the well through the treatment facility and to the distribution system.  The well pump was replaced with a new vertical turbine pump with a higher head since there are additional headlosses from the filters and associated piping than what the original pump experienced pumping directly into the system.  The pressure filters contain anthracite and manganese oxide coated media (GreensandPlus).  Manganese is removed through a combination of oxidation, filtration and adsorption processes.

Process residuals from the pressure filters are handled on-site using two lined residuals lagoons and on unlined infiltration basin. Backwash residuals from the filters will contain concentrated manganese residuals.  The two lined lagoons are designed to operate one on-line at a time, so that when one needs to be cleaned out, the other will be used.  As the filter backwash water flows through the lined lagoon, manganese residuals settle to the bottom of the lagoon and clarified water flows out of the top of the lagoon at the opposite end to the infiltration basin.  The clarified water infiltrates back to the ground.  The liner is used to prevent groundwater infiltration in the residuals lagoons in accordance with the requirements of the Massachusetts Department of Environmental Protection Drinking Water Program.  

Construction of the project was funded in part through the Drinking Water State Revolving Fund (DWSRF) as administered by the Massachusetts Water Pollution Abatement Trust and Department of Environmental Protection.  CEI provided design, permitting, bidding, construction and funding administration services.  CEI’s scope included design of all site, process, architectural, structural, plumbing, heating, ventilation, electrical, instrumental and controls needed for a fully functioning facility. 

For more information on manganese and treatment go to http://ceiengineers.com/innovations/water-supply/manganese.