RTW >Engineering Services >West Jefferson County Metro District

West Jefferson County Metro District
Wastewater Facility Masterplan & Treatment Plant Expansion

RTW worked with the District to determine the most feasible expansion scenario for the existing extended-aeration activated sludge plant. Advanced treatment comprised chemical feed for phosphorus removal and deep-bed filtration. Plant site area and access was limited and factored heavily in the alternatives analysis. Work included preparing a facility masterplan, performing a CPE on the plant, outlining a phased expansion program, and assisting with the site application process and public information program.

RTW designed expansion of the plant to a peak-hour capacity of 1.6 mgd. Features included a UV disinfection system, modification of the existing package plant to provide anoxic zones and contact stabilization capabilities, two new dome-covered secondary clarifiers, a RAS/WAS pumping chamber, new blowers for the aeration basins, a nonpotable water system, and operations building upgrades. The biosolids handling facilities expansion included new sludge pumps, a rotary drum thickener, and two-cell aerobic digesters with aeration equipment located under a District vehicle maintenance facility. RTW also designed an earthen biofilter to control odors from both the headworks and biosolids buildings.