Laserfiche WebLink
These ground water elevations prevailed in borings CH-CR1 and CH-CR2 during packer testing. Boring <br /> CH-CR4 was dry to near the bottom of the hole during packer testing. <br /> The results of the eighteen packer tests are provided in the attached spreadsheet, Table 1 -Packer Testing <br /> Results. Haley & Aldrich's estimate of 1 x 10-1 cm/sec for an average, representative bedrock <br /> permeability is based on an interpretation of these data and our experience with similar rock masses. It <br /> should be noted that the packer tests conducted within approximately 20 ft of the ground surface were <br /> conducted within a blast halo from excavation of overlying rock and these test results were assumed to <br /> represent artificially high permeability results. In addition, test results for CH-CR4 are considered to be <br /> higher than the general rock mass because of the lower quality rock encountered there on a structural fold <br /> as discussed above. <br /> Laboratory Testing Data <br /> Six rock core specimens recovered from the four core borings were tested for unconfined compressive <br /> strength. No point load tests were conducted because the foliated nature of the rock can be expected to <br /> result in misleading test results. Four of these specimens (Specimen ID Nos. 1 through 4) were chosen <br /> to be representative of the predominant rock material encountered in the borings. The other two <br /> specimens (Specimen ID Nos. 7 and 8) were chosen to test the minor intervals of poor quality rock <br /> encountered. The following table summarizes the results. <br /> Table 2 - Unconfined Compression Strength Test Results <br /> Specimen ID Boring ID/ Unconfined Strength <br /> Depth (ft) (psi) <br /> 1 CH-CR3/31.5-32.0 21,220 <br /> 2 CH-CR3/42.2-42.9 22,060 <br /> 3 CH-CR2/74.0-74.5 23,390 <br /> 4 CH-CR2/18.8-19.7 11,550 <br /> 7 CH-CR4/23.6-23.9 3,700 <br /> 8 CH-CR4/58.8-59.5 3,390 <br /> Notes: <br /> 1. All specimens were 1.875 inches in diameter <br /> 2. A length/diameter correction was applied to specimen 7 <br /> RP08267.200 5 <br />