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• <br />CJ <br /> <br />Appendix B - Packer Test Methods and Results <br />3 <br />2.3 Test Methods for Very Low Permeability Conditions <br />Four types of tests were typically performed to determine the hydraulic conductivity of the very low- <br />permeability test intervals: a flow test, a shut-in test, and injection test, and a bleed-off test. <br />Pmax <br />W <br />K <br />7 <br />to <br />y <br />W <br />a <br />Pe <br />from formation. , increase with time. Estimate P,. Pm,, and drop in pressure vs. time after closing : expulsed and corresponding drop <br />7- P--- valve in -ssllrp_ <br />Figure 2. Typical Packer Test Pressure Response <br />- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - <br />Equilibrium Pressure <br />- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ----------------- <br />low Shut-In Injection Bleed-off <br />TIME <br />Measure flovy rl..s alive klea nn> valve Inle h-f-far Measure 0 evalve Measurevchurne <br />The test stages are described below: <br />1. Open flow. After the packers were set, if there was a positive pressure at the collar of the hole, it <br />was allowed to flow. The flow rate was measured, and measurements continued until a stable flow <br />was reached. For very low permeability rock, there was essentially no flow. <br />2. Initial shut-in. After the flow measurement, the system was de-aired, the flow valve was shut, and <br />the pressure was allowed to rise towards its equilibrium state. <br />3. Injection. After the shut-in test, the valve to the hand pump was opened, and water was injected to <br />the packer stem using the hand pump. Enough water was injected to raise the water pressure in the <br />stem significantly above the expected equilibrium pressure. The volume of water injected was <br />monitored and recorded (number of strokes times stroke volume), along with the resultant pressure <br />change. <br />4. Falling head test. Following the injection of the water from the pump, the flow valve was shut, and <br />pressure in the packer stem was monitored as it decreased towards the equilibrium pressure. <br />5. Bleed-off. After the pressure had approached equilibrium, the remaining pressure was bled from <br />the system rapidly, taking two or three steps to return the pressure to zero (Figure 3). For each <br />4109B.071116 Whetstone Associates