PERMFILE72278

• Permit No: C1981071
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: PR2 APPENDIX III WYOMING DEQ MEMORANDUM & APPENDIX IV MASS STABILITY INVESTIGATION
• Media Type: D
• Archive: No

December 1986 5 863-2060
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3.0 LABORATORY TESTING
Historic mine data are available which describe the geotechnical
properties of mine spoil and Mesaverde bedrock samples obtained
from Area 51, which is located immediately north of Area 9/10.
Because of the similarity of materials sampled in Area 51 and
Area 9/10, the geotechnical properties of the analogous materials
in the two areas are inferred to be similar. Gradation curves
for two Area 9110 mine spoil samples tested (ASTM D422) are pre-
sented as Figures 9 and 10. Pertinent Area 51 laboratory test
data are presented in Appendix B.
The Area 9/10 spoil samples tested are characterized as a well-
graded gravel with little to some sand, silt, and clay and
abundant cobbles and boulders composed of sandstone, siltstone,
and claystone fragments. Laboratory testing of Area 51 spoil
materials indicates similar gradation and composition. As shown
in Appendix B, consolidated, undrained triaxial compression test
data are available for Area 51 bulk spoil materials. Such test-
ing indicates that mine spoil has an effective friction angle (~)
of 33 degrees and a cohesion (C) of 300 psf.
Direct shear test data are available for a core specimen obtained
from the shale that underlies the Wadge coal seam in Area 51.
The testing was performed on a natural bedding plane joint in the
rock to .simulate the worst-case condition of sliding along a
plane of weakness. It indicates that appropriate strength param-
eters for this case are ¢ = 25 degrees and C = 1,400 psf.
In addition, historic mine dat
Atterberg limits, and uniaxial
samples collected from Area 51.
Appendix B.
a include moisture content,
compression test results for
These data are tabulated in
Golder Associates