The following reconnaissance work and planning should factor into the design of a pumping test: Proper planning includes the design of the test, acquisition and preparation of field equipment, measurement and control of flow rates, measurement locations and schedules (with pre- and post-test collection periods) for water levels, disposal of pumped water and test duration. Prior to performing a pumping test in the field, one should spend time in the office developing a thorough plan for the test. Diagnostic tools such as derivative analysis are useful for identifying flow regimes and aquifer boundaries from a pumping test prior to performing curve matching. Typically, aquifer properties are estimated from a constant-rate pumping test by fitting mathematical models (type curves) to drawdown data through a procedure known as curve matching (Figure 2). Estimation of aquifer properties by matching Theis (1935) type-curve solution to time-drawdown data collected in an observation well during a constant-rate pumping test in a nonleaky confined aquifer (data from Walton 1962). Pumping tests can identify and locate recharge and no-flow boundaries that may limit the lateral extent of aquifers as well. In layered systems, one also uses pumping tests to estimate the properties of aquitards (vertical hydraulic conductivity and specific storage). For the pumped aquifer, one seeks to determine transmissivity, hydraulic conductivity (horizontal and vertical) and storativity (storage coefficient). The goal of a pumping test, as in any aquifer test, is to estimate hydraulic properties of an aquifer system. Typical well configuration for pumping test in nonleaky confined aquifer. If you're testing the performance of a pump, use pump test if you're testing the performance of an aquifer through the action of pumping a well, use pumping test. Pumping Test or Pump Test? Although the terms pumping test and pump test are often applied interchangeably, the use of pumping test is preferred ( Woessner and Anderson 2002). In petroleum engineering, a pumping test is referred to as a drawdown test. Aquifer test and aquifer performance test (APT) are alternate designations for a pumping test. A pumping test is a field experiment in which a well is pumped at a controlled rate and water-level response ( drawdown) is measured in one or more surrounding observation wells and optionally in the pumped well (control well) itself response data from pumping tests are used to estimate the hydraulic properties of aquifers, evaluate well performance and identify aquifer boundaries.
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