C150063 Feasibility Study

• Contract/PO #: C150063
• Contractor Name: Jackson Lake Reservoir & Irrigation Company
• Contract Type: Loan
• Water District: 1
• County: Morgan
• Bill Number: SB 94-29
• Loan Projects - Doc Type: Feasibility Study

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the dam embankment, and noted the location of borrow material test pits. This
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information has been used to evaluate construction quantities in the evaluation of repair

alternatives, define a typical dam cross-section, and in development of the site

topography to be used in the final design plans.

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During the site visits, the dam facing, the upstream toe of the dam, and
potential borrow pits were observed and photographed.

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Field Investigations
1. In late summer 1994, Kumar and Associates performed a subsurface
exploration to investigate the existing upstream toe of the dam and to
evaluate potential borrow sites for construction materials. A copy of this
report dated October 17, 1994 is enclosed in Appendix D. This investigation
excavated pits at the toe of the dam and in the lakebed. Materials were
logged and sampled, and basic laboratory tests performed to identify and
characterize the materials. One primary purpose of the investigation was to
investigate if voids or loose soil areas were evident at the toe of the dam,
near historic sinkholes along a limited section of the. da":1' The conclusions
of this portion of the investigation were that there was no evidence of voids
or unusually loose soils below historic sinkhole sites,

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This investigation also excavated pits in the lake bottom to observe the
lakebed soil profile and materials, and evaluate their potential usefulness as a
construction material. Material samples were taken for laboratory evaluation.
The materials classification ranged from clean sands to silty-clayey sand and
very sandy clay.

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2. In fall of 1996, Kumar and Associates performed a second site exploration to
evaluate the depth of the concrete slab cutoff wall constructed at the toe of
the concrete slabs and to identify the extent of soils usable for soil cement,
A copy of this report dated July 31, 1997 is also enclosed in Appendix D,
This investigation excavated fifteen additional pits at the upstream toe of the

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