2004-05-20_REVISION - M2000158 ‎(2)‎

• Permit No: M2000158
• IBM Index Class Name: Revision
• Doc Date: 5/20/2004
• Doc Name: Technical Revision
• From: Environment Inc.
• To: DMG
• Type & Sequence: TR2
• Media Type: D
• Archive: No

PLATTE SAND Sa GRAVEL LLC PAGE Z
TECHNICAL REVISION
MAY ZO. 2004
it discussed the up gradient and down gradient impacts associated
with the slurry wall. As can be seen they say that they would expect
to find a two foot increase in the up gradient ground water level and
little or no impact along the down gradient side due to the close
proximity of the South Platte River. They also say the this will
create minimal impacts to the ground water table that can be miti-
gated. This water table increase would be along the south side of
Sharkey's Lake and the mounding would be contained entirely on the
mine site. The report suggests putting a surface ditch along the
south side of Sharkey's Lake will alleviate the increased water
buildup by diverting the water around the lined area. Platte Sand &
Gravel LLC will follow their recommendation.
TECHNICAL REVISION #2
Attached are two maps Exhibits F-1 and F-2 showing the location
of the slurry wall that will surround Longhorn Lake and the northern
part of Sharkey's Lake. We estimate that it will take two years to
complete the Longhorn Lake and 5 years for the Sharkey Lake area.
Initially the slurry wall will be installed around the Longhorn Lake,
it will be stripped and dewatered. Once this is done mining will
begin, with some of the material being moved to the processing plant
and some will be stockpiled in the Bluff Lake area. The topsoil will
be stored on the north end of Bluff Lake for use in reclamation. We
expect to use 85.00 acres ! of the Bluff Lake area for these tempo-
rary stockpiles. Since these are the first two areas to be mined we
feel providing larger scale maps would help when reviewing this
Technical Revision. Once these areas are done plans will be made for
the remaining lake areas. A Technical Revision(s) will be filed once
we know what changes will be needed to update the groundwater impacts
and lake configurations for the rest of the mine area.
TECHNICAL REVISION #3
A revised bond estimate is attached also, it includes a cost
for the slurry wall around Longhorn Lake and the revision to the
amount of disturbance necessary to reclaim the site outside the lake
areas.
A check for $188.00 is attached to cover the Technical Revision
fee. If you have any questions please call myself at [phone]
or Steve O'Brian of Environment, inc., at [phone].
Respec y su to
r
Rocky Hoffsctsne.
General Manager
cc Environment, Znc.
File
enclosures