Chatham Water & Wastewater Facility O&M
Weston & Sampson was retained to provide daily operation and maintenance services at Chatham’s water and wastewater treatment facilities until the agreement comes up for renewal again in 2014. Tasks include operation, maintenance, monitoring and optimization, cost/benefit analyses, cost savings evaluations, and non-routine/emergency maintenance.
The wastewater treatment facility provides secondary treatment for approximately 116,000 gallons per day (gpd) of municipal wastewater and approved accepted sludge. The treatment facility and associated pumping stations are monitored by a SCADA telemetry system with PLC software.
The wastewater treatment facility is an extended aeration plant that utilizes the activated sludge process to treat both sewage and septage with nitrogen control. This is accomplished using the Modified Ludzack-Ettinger process. The facility consists of a coarse bar screen, six-inch parshall flume, four aeration tanks with surface aerators, one mechanically aerated sludge holding tank, two secondary clarifiers, and a sludge dewatering building with two one-meter belt filter presses. The final unchlorinated effluent is discharged to four sand infiltration beds.
In 1997, the Town of Chatham and the Massachusetts Department of Environmental Protection (MassDEP) agreed to limit the facility’s discharge to 150,000 gpd annual average, with total nitrogen control using the previously mentioned Modified Ludzack-Ettinger process. The facility is equipped with a propane-fueled emergency generator to provide an uninterrupted level of treatment.
All of the Chatham sludge is delivered to the Yarmouth wastewater treatment facility and subsequently reloaded into dump trailers, then hauled to Soil Preparation, Inc. in Plymouth, Maine. At Soil Preparation, the sludge is lime-stabilized using the patented N-Viro soil stabilization process, and is then marketed to Maine’s farmers as a soil (pH) amendment.