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SECTION 3 WELL PERFORMANCE 3 . 0 Performance Tests The Contractor should utilize the same pump used for development work to perform the following set of pumping tests in each well. Pumping tests shall consists of: a. A step-drawdown test at 25, 50, 75, 100, and 125 percent of a maximum flow rate determined during development. Each step shall be maintained for 15 minutes. The water level shall be measured by the contractor every three minutes. b. A constant rate discharge test at a rate determined during (a) conducted for six hours, followed by recovery for two hours, or until static water level is reached. 3 . 1 Test Methods During each test, the discharge of the pump shall be measured with an accurate totalizing meter, a circular orifice meter, a venturi meter, or a velocity probe, approved by the supervising geologist. The pump discharge shall be maintained at all times during the test within plus or minus five percent (5%) of the pumping rate by means of a gate or similar type valve. Prior to the start of the test, the static, or non-pumping level shall be determined. The static water level shall be considered to be attained when three succes- sive water level measurements, spaced 20 minutes apart, show no appreciable rise in water level in the well. 3 . 2 Step Drawdown Procedures Each six hour well performance test will be conducted according to the following schedule: a. Turn pump on to approved test pumping rate at time (t) = 0. b. Contractor shall measure and record depth to water as follows: 1) Each minute, from t = 10 minutes. 2) Each 2 minutes, from t = 10 minutes to t = 20 minutes. 3) Each 5 minutes from t = 20 minutes to t = 50 minutes. 4) Each 10 minutes from t = 50 minutes to t = 100 minutes. 5) At t = 120 minutes, t = 150 minutes, t = 180, t = 300 minutes, and t = 360 minutes. 3 - 1