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<br />16 | Final Report Bay Area Clean Water Agencies | City of San Leandro <br />Table 5-3. Projected Costs and Nutrient Unit Costs for Sidestream Treatment <br />Parameter Units Ammonia/TN TP <br />Capital1 $ Mil 9.9 0.10 <br />Annual O&M $ Mil/yr 0.42 0.02 <br />Total Present Value2 $ Mil 19.3 0.48 <br />NH4-N Load Reduction3,5 lb N/yr 119,700 -- <br />TN Load Reduction3,5 lb N/yr 106,400 -- <br />TP Load Reduction4,5 lb P/yr -- 8,800 <br />NH4-N Cost 3,5,6 $/lb N 5.4 -- <br />TN Cost 3,5,6 $/lb N 6.0 -- <br />TP Cost 4,5,6 $/lb P -- 1.8 <br />1. Costs are referenced to the ENR SF CCI for November 2017 at 12,015. Costs do not include changes in solids handling or changes in <br />energy requirements in other unit processes. <br />2. PV is calculated based on a 2 percent discount rate for 30 years. <br />3. Based on cost for ammonia/nitrogen removal only. <br />4. Based on cost for phosphorus removal only. <br />5. Based on the average annual load reduction over the 30-year project duration. The calculation considers days with no discharge. <br />6. The unit load reduction cost was calculated by dividing the total present value for the nutrient of interest by the nutrient load reduction over <br />the 30-year projection duration e.g., Total PV for TN Removal divided by (Annual TN Removed times 30-years)). <br />6 Nutrient Reduction Upgrades <br />There are several technologies that could be applied at the SLWPCP to meet the Level 2 and Level <br />3 nutrient removal targets. The general approach taken was to consider Level 3 nutrient removal as <br />a potential endpoint for all facilities. The intent is to avoid situations where the recommended <br />facilities to meet Level 2 would require the construction of facilities that would be stranded in a future <br />upgrade to meet Level 3. <br />The technologies selected for this evaluation represent established technologies that are appropriate <br />for determining planning level costs and space requirements. SLWPCP should evaluate other <br />available technologies that may be available and applicable if nutrient reduction becomes a <br />requirement in the future. <br />6.1 Plant Upgrades to Meet Level 2 <br />The technology upgrades considered to meet the Level 2 discharge requirements build on those <br />presented under the Optimization Section. The process flow diagram for Level 2 upgrades is <br />presented in Figure 6-1. As shown, metal salt and polymer chemical feed facilities would be added <br />at the primaries to operate in CEPT for reducing the downstream facility needs (similar to <br />Optimization Concept). A parallel MBR would be constructed in the area where the current old fixed <br />film reactor is located. The existing aeration basins would be modified to operate as a biological <br />nutrient removal (BNR) reactor. In order to do this, the reactors would be operated in series (similar <br />to the optimization concept) plus there would be anaerobic/anoxic zones fully outfitted with the <br />appropriate mixed liquor return pumping between the zones. Other process improvement <br />technologies to consider include IFAS (integrated fixed film activated sludge) and moving bed <br />bioreactor (MBBR).