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Whetstone' <br />Associates <br />PLASTIC TURING <br />AIR LSF <br />PRESSURE REGULATOR <br />STUFFING <br />SOX <br />NITROGEN CVUNDE <br />CORE DRILL ROD <br />YFS<11NF <br />1NJECT10N <br />PRESSURE GAUGE <br />, <br />GROUND SURFACE <br />BOIIENOLE <br />Technical Memorandum <br />FO MUD NG i LOW METER <br />GLOBE VALVE <br />t - _ NON - SURGING <br />PUP <br />GLOOM <br />+ - BYPASS VALVE <br />1 ►� <br />OVERFLOW TO TANK <br />Figure 2. Example Above -Ground Assembly for Packer Permeability Tests <br />The packer will be inflated using nitrogen gas from a high pressure cylinder connected to the down - <br />hole assembly via a regulator and airline. There must be enough slack in the airline to allow full <br />movement of the sliding ends of the packers without creating tensional stress on the fittings. A full <br />inspection of the packer assembly and a trial inflation to 300 psi will be performed before <br />deployment to look for nitrogen leaks. Short sections of steel pipe with approximate diameter of the <br />borehole will be used to cover each packer during the trial inflation and soapy water will be used to <br />inspect connections for gas leaks.. The airline will be zip -tied to the standpipe at ten- to 20 -foot <br />intervals to prevent excessive slack which could snag on the walls of the borehole. <br />Packer inflation pressure will be determined for each interval based on submergence so that the <br />pressure is sufficient to compensate for the hydrostatic head on the section, the seating requirements <br />of the packer, and the maximum differential pressure that will be created between the test zone and <br />the overlying water column. The potential maximum hydrostatic head on the section will be about <br />750 feet (320 psi). The maximum differential injection pressure will be about 150 psi. The potential <br />maximum inflation pressure for the packer assembly will be about 500 psi. After the packers are <br />seated, it is necessary to wait for water levels to stabilize in the packed interval before beginning the <br />injection permeability tests. Typical wait times are 10 minutes to more than one hour, depending on <br />the formation permeability. <br />Permeability tests for each interval will be performed in three to five steps of about three to five <br />minutes duration each. Water will be injected into the formation during each step at constant <br />pressure until the flow stabilizes. The flow will then be recorded for a three minute interval. Stable <br />flow is an important condition of the test prior to recording the data, and in some cases, the <br />procedure may require additional time to meet the stability criterion. Each section will be tested at <br />three to five pressure steps starting at about 15 psi on the surface gauge and stepping up to a <br />maximum of about 60 to 80 psi before stepping back down to the initial injection pressure. The total <br />differential pressure on the section will be equal to the pump head (gauge pressure) + elevation head <br />(pressure caused by the weight of the water column above the shut -in static water level) — frictional <br />4109C.120309 6 <br />