C150094 Contract

• Contract/PO #: C150094
• Contractor Name: La Plata Water Conservancy District
• Contract Type: Grant
• Water District: 0
• County: La Plata
• Bill Number: HB02-1152
• Loan Projects - Doc Type: Contract Documents

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Exhibit A
Grant for Proposed Feasibility Study of Long HolIow Reservoir and Red Mesa Reservoir Enlargement

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o Determine NEP A requirements for the proj ect.

o Determine the potential for Threatened & Endangered Species issues to
impact the feasibility of the project.

o Evaluate the potential for wetland issues to impact the feasibility of the
project.

o Determine the extent of potential impacts to cultural resources.

o Evaluate potential fmancial and institutional constraints to determine whether
there is a fatal flaw.

o Determine affects of the Project on the Indian Trust Assets of Native
American tribes and nations.

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Study Plan - Phase I Initial Feasibility (Fatal Flaw) Analysis

Each work task is described below. Cost estimates for each task are presented in Table

3a.

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Review Existing Data

WWE will review pertinent published information from the U.S. Geological Survey
(USGS), the USBR and the Colorado Geological Survey to obtain an understanding of
the site geology and the potential requirements for design and construction of a dam and
reservoir at the site.

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Topography

The topography ofthe site will be assessed by conducting aerial photography and
surveying the site to provide horizontal and vertical control. This work will allow
production of an orthophoto of the site, with a contour interval of 2 feet, to be produced.
The orthophoto will provide the basis for development of accurate area-capacity tables.

Geologic Reconnaissance

A reconnaissance will be made of the dam and reservoir area to observe the surface
geology, estimate groundwater seepage patterns and gain familiarity with site conditions.
Data obtained during the geologic reconnaissance will identif'y structural geology,
groundwater, seismicity and geologic hazards, which must be considered in the design
and construction ofthe dam and reservoir. The information obtained will be used to
assist in selecting preliminary alignments for the embankment, the spillway and outlet
works.

Groundwater Hydrology

The specific hydrologic conditions that affect surface water flow in Long Hollow Creek
and its tributaries will be analyzed to determine if water supplies will be adequate to
maintain ",vater storage in the reservoir at levels that will allow the facility to function as
intended. These hydrologic conditions include both irrigation return flows and diversions
from the La Plata River. Some existing long-term data will aid in the analysis and

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