PERMFILE63847

• Permit No: M1979097
• IBM Index Class Name: Permit File
• Doc Name: EXHIBIT F RECLAMATION PLAN MAP
• Media Type: D
• Archive: No

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subject to administration under the doctrine of appropriation.
Figure 6 shows the locations of known wells in the vicinity
of the mining site, These wells have been located to the .
nearest quarter-quarter section. The numbers on the map refer
to Figure 7 which lists information on file with the State
Engineer's Office for each well.
The sand and gravel overlie a bedrock of Pierre Shale. The
formation may be as much as 5,000 feet thick and yields only
small amounts of water to wells where fractured extensively.
The Pierre Shale is underlain by the Dakota sandstone, which
can yield as much as 25 gallons per minute to wells.
Since the gravel of the alluvial aquifer is to be mined dry, a
dewatering trench will be excavated around the area prior to
mining. Ground water which seeps into the trench will be pumped
out. The pumping will be monitored under NPDES permit No. CO-0036200.
Dewatering will lower ground water levels in the vicinity of the
excavation, The depth to water varies from 1 or 2 feet near the
Poudre on the northeast to 8 or 10 feet in the terrace west of
the mine area. The saturated thickness of the sands and gravels
ranges from 8 to 15 feet across the area. Ground water contour
information was assembled from test hole information provided
by Flatiron. The Pierre Shale which forms the lower boundary
of the alluvial aquifer has been eroded creating an uneven
bedrock topography. Vertical ground water movement is controlled
G- 3