included in the test report. The complete test report will include the following:
1. Initial static water level
2. Pumping rates, at least every hour
3. Drawdown data, at least every hour
4. Rate of recovery
The simplest way to measure the water pumped is to catch it in a steel drum or other tank of known volume. The time required to fill the tank is determined as accurately as possible. The rate of pumpage in gallons per minute is then calculated. For reasonable accuracy, the tank should be large enough to hold the water pumped during a period of at least 2 minutes. This limita- tion makes the method practical only for relatively small wells, since large tanks will not usually be available.
Water meters offer a definite advantage in measuring the water being pumped. The amount of water pumped may be recorded from the meter at desired intervals. The total discharge may be recorded for any individual phase of the draw- down test.
The most accurate way to measure depth to the static level and to the pumping level in a well is with a chalked tape. A steel tape with a weight to make it hang straight is chalked at the lower end with blue carpenter's chalk and lowered into the well until 1 or 2 feet of the tape is submerged. The proper length to lower the tape may have to be determined by experiment. The wetted length of the tape shows up very clearly on the chalked portion of the tape. This length is subtracted from the total length lowered below the reference point; this gives the depth to water.
The drawdown observed during a well test is the difference in feet between the
Table 9-1. - Daily Water Requirements in Temperate Zone
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