C153514 Feasibility Study

• Contract/PO #: C153514
• Contractor Name: Farmers Water Development Company
• Contract Type: Loan
• Water District: 60
• County: San Miguel
• Bill Number: SB 87-15
• Loan Projects - Doc Type: Feasibility Study

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3.4

Subsurface Exploration Program

3.4.1

3.4.2

Test Pits

Seven test pits were excavated in the embankment and
upstream dam foundation to obtain information on
embankment and foundation materials in the general
vicinity of the existing sinkholes. The test pit
locations are shown on Figure 4. The test pits were
excavated on March. 10, 1987 using a John Deere No. 6
backhoe owned and operated by the FWDC.

The materials and stratigraphy encountered in the
test pits were described and logged in the field.
Representative samples of typical materials were obtained
from sel ected test pits and packaged in pl asti c bags and
buckets for transport to SRK 's 1 aboratory in Lakewood,
Colorado. The test pit logs are included in Appendix B.

Boreholes

Eight boreholes (BH-l through BH-B) were advanced
through the embankment and into the foundation to obtain
classification and engineering property data. The
drilling contractor, Himes Drilling Company Inc. of Grand
Junction, Colorado, mobilized a truck-mounted longyear
HC44 drill rig to the site on March 15, 1987 and
completed the program on March 28, 19B7. Due to inclement
weather and deep snow, rig access was generally
restricted to the road along the dam crest. The eight
boreholes, ranging in depth from 40.5 .to 123 ft and
totaling 643.5 ft, were advanced at the locations shown
on Figure 4. The borehole logs are included in Appendix B
and are summarized on Figure 6.

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