Weaver Consultants Group (WCG) provided engineering design services for bidding and construction of a landfill cell as well as upgrades to the leachate pumping system at the Wabash Valley Landfill (the Landfill). The Landfill has a relatively small amount of leachate storage capacity of 60,000 gallons and has leachate with a high amount of biosolids that clog the typical submersible pumps the Landfill had been using. The Landfill has a direct discharge connection to the City of Wabash Waste Water Treatment Plant. The client needed to increase their discharge rate to the City in order to keep up with incoming leachate flows. The client also desired to increase the leachate storage volume in the tanks at any given time. For example, maintain an overall lower level in the tanks in order to have some surge capacity after precipitation events.
In order to increase the leachate discharge rate we had to find a pump that could handle the solids in the leachate as well as pump a higher volume. The standard multistage high-head pumps that are used in many landfill applications were not an option due to the need to handle the solids. WCG worked with Sligo to find a pump that would fit the Landfill’s needs. In order to maintain a lower level in the tanks on a consistent basis, Sligo recommended using a variable frequency drive (VFD) that would vary the speed of the pump to maintain a target level in the tank.
In order to complete the project, multiple Practice Groups were utilized. North Central Solid Waste developed the initial design parameters and project objectives. NCSW then contacted Sligo to assist in the design process and provide recommendations on pumps, panels, and the VFD’s in order to achieve the client’s goals. Once the design process was completed the project, including construction of a landfill cell, was bid out to contractors. Ultimately, the landfill cell portion of the project was eliminated so the client needed to find a contractor to install the leachate pumping system components. At this point, Landmarc was brought in to provide the client with a price to install the components and the client decided to use Landmarc for the installation. Landmarc successfully installed the system including programming of the control panel and VFD and performing an initial start up to verify the system was functioning as intended.