PROJ00455

• Contract/PO #: C153583
• Contractor Name: Ute Water Conservancy District
• Water District: 0
• Bill Number: XB 99-999
• Loan Projects - Doc Type: Feasibility Study

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during the excavation for a pipeline. Also, the buried pipe along 1-70 will require
special permitting and right-of-way considerations from the Colorado Department
of Highways (CDOH) and Federal Highway Administration (FHW A). Due to
limited space available during the construction of the subject pipeline the right side
lane of east bound lanes of 1-70 would have to be closed. CDOH has indicated that
under no circumstance will permission be granted for closure of any lanes on 1-70
in this area.

· A pipeline along SH 65 to 1-70 and then supported above 1-70 by rock-bolting the
pipeline to the canyon wall. The unstable conditions of portions of the valley walls
as evidenced by rock slides near SH 65, would require extensive rock stabilization.
The design would also require a bench cut into the rock in the Plateau Canyon wall
and a pipeline supported on this bench and laterally supported by means of rock-
bolts. The construction of such support system would be difficult due to lack of
adequate space to mobilize construction equipment. Furthermore, in the event of
pipeline failure, water from the failed pipeline could trigger landslides which would
effect the safety of motorists on 1-70. This option also would be subject to the same
CDOH lane closure restraints as noted in the preceding alignment discussion.

As indicated above, each of these alternatives present a series of design, permitting, construction,
and maintenance problems, therefore, they were not investigated any further.

6.2 Subsurface Condition

The subsurface conditions expected along the proposed bypass pipeline alternative alignment are
fairly variable. Due to this variation in subsurface conditions the proposed alignment was divided
into 10 segments. The subsurface conditions expected along each of these sections are as follow:

Section 1 (from Station 718 + 00 to 737+50)
The subsurface condition along this section can be characterized by relatively thin
layers of alluvial and colluvial deposits mainly consisting of sand. gravel and boulders
overlaying the sandstone bedrock. The depth to bedrock is estimated to be from 5
to 10 feet below the existing ground surface with the exception of a rock which is
located at about Station 720+00. At this location bedrock may be present I to 2 feet
below the existing ground surface. Groundwater along this section at the proposed
pipeline installation depth is anticipated to be non-existent.

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