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Name: Todd A. Blomstrom Date: October 8, 2020 Page: 3 With the bottom elevation of the upstream Manhole 2 at 872.44’ and using the proposed parameters, the lead pump would turn on before wastewater would back up in the gravity pipe as far as Manhole 2 and the entirety of the gravity pipe would empty into the wet well before the station shuts off. Table 3, below, details the estimated costs associated with Option 1. Table 3 - Option 1 Cost Estimate Item Cost Mobilization $15,000 Allowance $10,000 Site Grading/Restoration $7,000 Existing Station Demo $6,000 Bypass Pumping $15,000 Pumps/Controls $87,000 Electrical $15,000 Control Panel Pad $4,000 Site Work (Seeding, Drive, etc.) $7,000 Valves, Piping, Misc. $20,000 Construction Subtotal $186,000 Contingencies (20%) $37,000 Construction Total $223,000 Option 2 - Replace the Existing Station The second option includes constructing a new submersible lift station to replace the existing station. A new deeper precast wet well would provide a greater distance from the influent gravity pipe to the bottom of the structure, preventing flooding upstre am. Significant components include the following: - Construction of new duplex submersible lift station with precast wet well and valve vault - Installation of new lift station controls and SCADA equipment - Installation of two new submersible pumps and piping - Demolition of existing wet well/valve vault lift station Based on station operating data from recent years and the need to maintain minimum flow velocity in the force main, the new submersible pumps would be rated for the same 100 gallon per minute with a total dynamic head of 33 feet. Based on these parameters, the wet well would consist of a 6’ diameter precast concrete manhole. However, to prevent the flooding of the manholes upstream the base elevation of the Lift Station would be 868.5’, 25.5’ below grade and deeper than the current wet well. Table 4 outlines the estimated costs associated with Option 2.