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CITY OF SANTA ANA RFP NO.: 21-059 WATER WELL, PUMP AND MOTOR REHABILITATION AND REPAIR SERVICES a. Discharge Water 1. Discharge water shall be conveyed from the pump to the point of discharge at the well site. It is imperative to ensure that no damage by flooding or erosion is caused to the chosen drainage structure or water disposal site, or to nearby lands and/or streets. 2. The Contractor shall provide all piping and discharge lines. The point of discharge location will be provided by the City and the Contractor will be responsible for all devices and piping to convey the water to that discharge point. 3. No fluids will be permitted to flow offsite (except to proper drainage facilities) or to properties not owned by the City. All discharges will meet the requirements of the City's NPDES permits and Orange County Flood Control permits. b. Step-Drawdown Test 1. Prior to starting the step-drawdown test in the well, the static, water level shall be measured. The well shall be "step" tested at rates determined by the City. The step-drawdown test for the well is estimated to require approximately 12 pumping hours with each step being 3 to 4 hours in duration unless specified otherwise. 2. The Contractor shall operate the pump and change the discharge as directed by the City. Both a gate valve and an engine throttle shall control the discharge of the pump unless specified otherwise. The discharge shall be controlled and maintained at approximately the desired discharge for each step with an accuracy of plus or minus five (5) percent. 3. Pump discharge shall be measured with an instantaneous flow meter dial and a totalizer meter and stopwatch, as approved by the City. Both an air -line and electric sounder shall be furnished by the Contractor for water level measurements. During the step-drawdown test, the Contractor shall record sand content measurements at 30-minute intervals. c. Constant Rate Discharge Test 1. After a 24-hour recovery period from the end of the step-drawdown test, the City may request the Contractor to perform a constant -rate discharge test. This test shall be run for a period of 24 hours, or until the pumping level remains constant for at least 4 hours, or until the City terminates the test. A recovery period of 24 hours shall follow the termination of the constant -rate discharge test, at which time the City will collect residual drawdown (recovery) data. 2. During the constant -rate discharge test, the Contractor shall also conduct the final sand content testing. The sand content shall be determined by averaging the results of samples collected at the fallowing times during the final pumping test: i. Five (5) minutes after start of the test ii. After 1/4 of the total planned test time has elapsed ill. After 112 of the time has elapsed iv. After 3/4 of the time has elapsed v. Near the end of the pumping test Aborted Tests 1. Whenever continuous pumping at a uniform rate has been specified, failure of pumping operations for a period greater than one (1) percent of the elapsed pumping time shall require suspension of the test until the water level in the pumped well has recovered to its original level. 2. Recovery shall be considered "complete" after the well has been allowed to rest for a period at least equal to the elapsed pumping time of the aborted test, except that if any three (3) successive water level measurements spaced at least 20 minutes apart show no further rise in the water level in the pumped well, the test may be resumed immediately. 3. The City shall be the sole judge as to whether this latter condition exists.