INSPEC04521

• Permit No: M1977304
• IBM Index Class Name: Inspection
• Doc Name: MINERALS PROGRAM INSPECTION REPORT
• Inspection Date: 2/20/1997
• Media Type: D
• Archive: No

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I~INH"i ID # OR PROSPECTING ID # M-77-304
INSPECTION DATE 2-20-97 INSPECTOR'S INITIALS GSC
. OBSERVATIONS
This inspection was conducted to determine if the current financial warranty amount of
$100,858.87 is sufficient to complete reclamation of the permit. The Division
representatives checked in with Mr. Randy Crowe of Colorado Lien Company. This was a follow-
up to an inspection conducted on the previous day with the operator's representative, Mr.
Nathon Barton of Pete Lien ~ Sons.
The permit is located on the slopes of an eastward dipping `hogback' ridge. The limestone
deposit lies beneath a sandstone cap with an approximate dip of 15 degrees to the east.
Mining begins near the top of the ridge and works down slope to the east. The operation
consists of drilling and blasting the overburden and limestone. The overburden spoils are
hauled to the top of the ridge and stockpiled for backfilling during reclamation. The
limestone is excavated with loaders, screened and crushed, and hauled to the processing plant
located west of the hogback ridge. The total thickness of the excavated overburden and
limestone is about 40.' Spoil material which has been hauled to the uphill side of the
excavated pit is stockpiled in a broad, level berm with an average width of about 250' from
east to west along the top of the ridge. At the base of the operation along the east side
of the pit, spoils had been cast downhill to create a level bench with an average cross
sectional width of approximately 150.'
The reclamation plan calls for concurrent mining and reclamation. The plan includes
backfilling and regrading the pit with spoils, covering with a growth medium consisting of
topsoil and crushing fines, and reseeding. The growth medium is augmented with excess
topsoil material obtained from a sugar beet operation. Various portions of the pit have
already been partially to completely backfilled and graded and one area of the permit has
been reseeded. The extreme northern end of this pit. is pre-law mining and is not included
in the reclamation calculations.
The Division measured the pit dimensions with a wheel and the pit slope with a brunton and
alidade and created typical cross sections for volumetric calculations. The cross sectional
measurements are outlined below. Based on these measurements, there is enough material
stockpiled in the uphill spoils piles and the downhill bench areas to backfill the bottom 20'
of the pit. The downhill bench volume was calculated at approximately 30% of the total
volume of material required to backfill the pit to a depth of 20' deep.
The bond evaluation will be based on the cost to backfill the existing pit to a depth of 20'
deep. About 70% of the total required volume will be calculated as a downhill push of the
spoils stockpiled along the western uphill side of the pit. An uphill push wily be required
for the remaining 30% of material now located in the bench along the downhill, eastern side
of the pit. The cost to remove refuse will be calculated for the Rex Quarry boneyard near
the southern perimeter of the permit.
Summary of Field Measurements:
1. Rex boneyard 665,600 cu. ft. refuse
2. Ridge top spoils stockpile - 250'horizontal distance
(downhill push) 10,880 sq. ft. cross section area
2800' quarry length (requiring backfill)
total volume 1,120,000 cu. yds.
3. Ridge bottom spoils bench - 150' horizontal distance
(uphill push) 2210 sq. ft. cross section area
2800' quarry length (requiring backfill)
total volume = 229,185 cu. yds.
4. Topsoil and fines replacement ® 6" x 80 acres = 64,533 cu. yds.