Tomahawk Creek Wastewater Treatment Facility Process Improvements Project

A. Odor Control Improvements: Installation of covers on the BNR Basin anaerobic and pre-anoxic basins, and addition of Odor Control System No. 4. Customized rubber mat covers will also be added to the BNR Influent Splitter Box and RAS Splitter boxes to mitigate odor complaints and improve operational flexibility for VFA production.

B. Sidestream Nitrogen Treatment Improvements: Separation of centrifuge startup/shutdown slop flows from the main centrate discharges and redirection to the plant drain to reduce solids accumulation in the Centrate Holding Basin.

C. Gravity Thickener H 2 S Reduction: Addition of ferric chloride feed capability to the Primary Sludge Gravity Thickener/Fermenter to reduce hydrogen sulfide generation and loading on odor control units.

D. Co-Thickening Improvements: Modifications to allow thickened primary sludge (TPS) to discharge directly to the Co-Thickened Sludge (CTS) wetwell, addition of a fifth digester feed pump for continuous mixing, and installation of pressure sensors on digester feed pump discharge piping with SCADA integration.

E. Sludge Cleanout Manhole: Addition of a sludge cleanout manhole over the (3) 4” CTS lines between the Solids Processing Building and Digester Control Building to facilitate future line cleaning.

F. Primary Clarifier Improvements: Construction of an access drive and installation of cleanouts for scum pit drainpipes, and addition of electric actuators to six PC Influent Slide Gates at the Headworks Building.

G. Micro-C Dosing Improvements: Replacement of potable water with Plant Effluent Water (PEW) as carrier water for Micro-C dosing, and rerouting of Micro-C discharge lines above grade for improved visibility and control.

H. Pre-Anoxic Mixers: Addition of a second submersible mixer in pre-anoxic zones PAX1-1 and 3-1 to facilitate the movement of scum out of pre-anoxic zones.

I. Digester No. 3 Access Improvements: Replacement of the existing 21-ft tall cageless ladder with a stair tower to improve safety and accessibility to the digester roof. Demo of existing ladder.

J. Chlorine Contact Basin Improvements: Replacement of all aluminum slide gates with corrosion-resistant materials due to chloride-induced deterioration.

K. Filter Complex Improvements: Installation of an electric actuator on the secondary effluent/filter influent gate for automated wet weather operation, and addition of safety platforms to the eight disk filter basins to enhance maintenance access and safety.

L. Storm Drain Isolation near Ferric Tanks: Installation of an isolation drainage system near the ferric chloride truck unloading station to prevent chemical spills from entering the storm sewer system, as identified by KDHE.