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 Electrical As many of the lower underground pipes have now been installed, the electric subcontractor, Smith Electric, worked throughout August to install trenchducts and cable trays across the site. They started pulling wire from the new transformers to the switchgear in the Electrical and Filter/Disinfection buildings. The electric utility connected the  feed power lines to the 2 new power transformers which were installed in June. Smith also began pulling wires from the switchgear to the individual motor control centers (MCCs). Wiring from the MCCs will eventually be pulled to the various pieces of equipment in the plant for power and control.
 Influent Pump Station The sheet piles which were installed for the excavation of the pump station were cut down to 5 feet below finish grade;the remaining lower length of the sheets will remain in the ground. The contractor continued to back- fill  and compact around the structure. The forms were constructed for the top slab of the pump station, then stripped after the concrete pour. As this treatment structure has the potential for creating objectionable odors, the atmosphere in the pump station will be contained and evacuated through a foul air handling system. This foul air will be scrubbed through 3 biofilters. Work on the biofilters included installation of drain and foul air feed lines. These filters will eventually be filled with media which promotes the growth of odor removing microorganisms. Foul air from the grit removal and solids thickening treatment units will also be treated by these filters.
 Grit Handling Work continued to install and connect the pumps and air blowers for this unit. Additionally, some of the final concrete work on the grit tanks themselves was completed.  Immediately adjacent to the grit tanks is a new vactor dump station. The City cleans its sanitary sewer piping (approximately 110 miles of pipe) using flusher/vacuum trucks (vactor truck). The material  cleaned from the sewer pipes will be dumped from the trucks into the dump station to be processed with the rest of the wastewater flowing through the plant. Work on excavation, rebar, concrete forming and pours for this structure was completed in August.
Oxidation Ditches (OD) The contractor was busy installing the stainless steel 12 inch air lines from the blower building to and through the ODs. Certain microorganisms (bugs) who live and work in the ODs removing the pollution from the wastewater must have oxygen to survive. These air lines deliver the air to the ODs and fine bubble diffusers dissolve the oxygen into the wastewater.
After the water is treated in these ODs, it’ll be piped to the secondary clarifiers. This effluent piping was being installed and connected to the ODs. Because the bugs in the ODs are always reproducing, the excess bugs have to be removed from the system to make sure there’s enough food the remaining bugs. Pumps and piping to remove these extra bugs were installed.
 Secondary Clarifiers More of the mechanical equipment continued to be installed in these three tanks. The contractor got acceptance from the manufacturer on the installation of some of the major equipment already installed. The contractor is also preparing the sloped bottoms of these tanks to receive the final finishing layer of grout.
 SEEPS Some work was done on the Secondary Effluent Equalization Pump Station (SEEPS) including embedding new rebar from the new structure into an existing structure (aeration basin) to tie the two structures together. The SEEPS will pump flow coming from the new secondary clarifiers through the flow equalization tank (the aeration basin will be modified for this purpose) to the final treatment process of tertiary filtration and disinfection.
 Solids Handling The Dissolved Air Flotation Thickeners (DAFT) may require the addition of special conditioning chemicals known as polymers. The foundation slab work for this polymer dosing station was completed. Finish work on the DAFT concrete walls was performed as well. The pipelines which will carry the thickened sludge from the DAFTs were tied in to the existing anaerobic digester sludge feed lines. The thickened sludge (called float) is scraped from the top of the water in the tank up onto a beach where it’ll fall into a pipe for pumping to the anaerobic digesters. These beach structures were dry fit in the concrete DAFT tanks before they will be coated.
The sludge in the anaerobic digesters must be maintained at body temperature (95 deg F/37 deg C) in order for the bugs living there to do their work. This required heat will be supplied by 2 new hot water boilers. These boiler units arrived in August and were positioned in the new boiler building for final installation. These boilers will fire on either natural gas or methane gas produced by the bugs in the digesters.
The east sludge lagoon (#1) was excavated and contoured to its final dimensions in preparation for the installation of the heavy duty plastic liner; the west lagoon (#2) was lined and put into service in June.
 Storm Water Pump Station Any rain water accumulated at the completed treatment plant site will need to be collected and safely removed in order to prevent flooding. Excavation and rebar work began on the pump station which will handle this water.
Since most of the yard piping work was completed at the south levee around the treatment plant, the contractor recontoured the levee to the original dimensions. This levee will be hydroseeded to prevent erosion of the soil.
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