PERMFILE106632

• Permit No: M1988112
• IBM Index Class Name: Permit File
• Doc Date: 3/2/1989
• Doc Name: GEOTECHNICAL EVALUATION FOR THE SOUTH WALL WEST PIT SAN LUIS PROJECT
• Media Type: D
• Archive: No

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The Santa Fe material generally has an SRMR (SRK/88) of less than 10%. The materal can be
easily broken by mild hand pressure. Isolated zones can be classified as a weak rock (3500 psi)
due to the high amount of calcite cement present.
The water table generally parallels the level of the Rito Seco and lies approximately y 5 to 20 feet
below surface. Hole D88-63 drilled in the 1988 geotechnical program (SRK/88) is shown on this
figure. It Iles approximately 94 feet to the west of the Interpreted section. It is employed for
purposes of continuity.
3.1 Field Permeability Testing
Falling head permeability tests performed by Halepaska and Assoc., employing the Hermit
ernironmental logger, had measured field permeabilities of 4 x 10~ cm/sec for the alluvium and
4 x 10"~ cm/sec for the Santa Fe materials (eolian). Similar measuremems were recorded by SRK
and are summarized In Appendbt III.
3.2 Laboratory Testing
Tables 2 and 3 summarize the results of the laboratory program that were pertormeci on eolian and
fanglomerate samples.
Table 2: Santa Fe Soil Characterization
Material Moisture Content Dry Density Soil Classification
Fanglomerate 6.0 142.0 Silty Sand with Gravel
Eolian 7.7 134.1 Silty Sand
Table 3: Santa Fe Laboratory PermeabillN Test
Material Measured Permeability (cm/sec)
Fanglomerate 4 x 10's (range 2.6 to 4.2 x 10"5)
Eolian 5 x 10~ (range 3.6 to 23 x 10-z)
Figure 3 and Table 4 summarize the triaxial testing conducted on the eolian material. Testing was
conducted in a saturated undrained state with pore pressures being recorded. The upper bound
refers to shearing of the Intact sample, whereas the lower bound identifies the available strength
that exists after the sample has been sheared.