PROJ00489

• Contract/PO #: C153486
• Contractor Name: Farmers Water Development Company
• Contract Type: Loan
• Water District: 0
• County: San Miguel
• Bill Number: SB
• Loan Projects - Doc Type: Contract Documents

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For cost estimating purposes, we have assumed that
SP and resistivity surveys will be run along the dam
alignment. Resistivity soundings will also be conducted
at selected locations to better define the geologic
column.

Drillinq, Samplinq and Field Testing

The proposed dri 11 ing program consists of from six
to eight boreholes located on the existing dam and
impoundment bottom. The purpose of the dri 11 i ng program
is to determine the subsurface stratigraphy, engineering
classifications and engineering properties for the
materials in the embankment and its foundation. Samples
of these materials will be taken at selected intervals
and depths for field classification purposes and later
laboratory testing. Field permeability tests using
borehole packers and flow meters will be conducted at
various depths in selected boreholes to evaluate the
relative permeability of the various strata. The test
results will be used to develop a conceptual model of the
possible subsurface flow patterns which are possibly
related to the historical sinkhole development. If water
losses during the permeability testing are large, dye
injection tests may be conducted at selected depths in an
attempt to determine the flow path(s) and possible outlet
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points.

The proposed boreholes are located either on the dam
crest or on the impoundment bottom near the outlet
conduit. The borehole pattern will be refined based on
the results of the backhoe test pit and surface
geophysical investigations to maximize the efficiency and
minimize the costs of the drilling program. Borehole
depths are expected to range from 40 to 100 ft with a
maximum embankment penetration of approximately 70 ft and

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