R2011-182 AUTHORIZING EXECUTION OF TASK ORDER NO. 16

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Phase II Tasks The Engineer will not proceed with Phase II without prior written authorization from the Owner. Engineer's Phase Il tasks shall include the following: 1. Meet with Owner and Engineer's subcontractor in Decatur to review detailed aquifer testing procedures and inspect test sites. 2. Employ the services of a subcontractor to conduct one (1) or two (2) aquifer tests, as determined from Phase I and authorized by Owner. A test production well, four (4) additional observation wells, and a lake stilling well will be installed for each aquifer test. Test production wells will be drilled to the bottom of the sand and gravel aquifer, anticipated to be roughly 80 feet below ground surface. Aquifer testing will consist of continuous, constant rate pumping over a ten (10) day period through a test production well to provide information for estimating the yield and design criteria for a new radial collector well. The subcontractor shall be required to pump the well during the test for the full period without shutdown. If a shutdown occurs during the test period which adversely impacts the ability to use the data to evaluate aquifer characteristics and collector well feasibility, the subcontractor will be required to repeat the test without cost to Owner. At the conclusion of the test, pumping will be stopped and recovery of water levels shall be monitored for at least 24 hours or until 90 percent recovery is obtained in the monitoring wells (whichever is longer). The pumped water from the well will be monitored every six hours and lake water quality every 24 hours for field determinations of temperature, pH, and specific conductance for estimation of total dissolved solids (TDS). Observation wells shall be left in- place at the end of testing, unless Owner authorizes abandonment and removal for an additional cost. 3. Collect one set of groundwater samples from each test production well near the end of the aquifer test. The subcontractor will coordinate with a water quality laboratory to obtain sample containers, preservatives, shipment coolers, and chain-of-custody forms. The samples will be analyzed for the following: temperature, pH, specific conductivity, iron, manganese, total hardness, alkalinity, metals, chloride, fluoride, nitrate, nitrite, sulfate, pH, TDS, turbidity, trihalomethanes, organics, pesticides, herbicides, and PCBs. 4. Compile and analyze field data collected in Phase 11. Prepare a draft technical 5 City of Decatur Task Order No. 16 Rev. 11-4-11