_REVISION - M1980245 ‎(3)‎

• Permit No: M1980245
• IBM Index Class Name: Revision
• Doc Name: Exhibit I & J ‎(Cont)‎
• Type & Sequence: HR1
• Media Type: D
• Archive: No

UNITED STATES DORTMENT OF AGRICULTURE • , v
SOIL CONSERVATION SERVICE 318 4th Street, Castle Rock, CO 80104
November 6, .1980
RECOMMENDATIONS FOR RECLAMATION OF THE "HOGBACK
OPEN-PIT MINE" FOR THE ROBINSON BRICK S TILE CO.
Locations NW}, Section 20 Township 7 South, Range 69 West,
SW}, Section 35, Township 6 South, Range 69 West,
Approximate Acreages 18
Present Land Use Soils and Ve station: The area is currently used for
livestock grazing and wildlife ha itat. The soils are classified as
stony steep land (SV) and range from cobbly and gravelly sandy loam to
clay loam in texture. Significant amounts of topsoil are very limited.
Slopes vary from 30-50 percent. The soils, climate and topography
support a shallow foothill range site with the major grasses being big
_ and little bluestem, mountain muhly, side-oats grams, prairie eandreed, _
and needle-and-thread. Frequent shrubs are mountain mahogany, skunkbush
sumac, waxcurrent, snakeweed, and fringed sage. Average annual production
for a site in excellent condition is 400 pounds per acre.
Post-mining Land Use; Livestock grazing and wildlife habitat.
Re r�adiogt As each stage is mined, the spoil will be placed on the pro-
coding stage in a benched configuration. This benching will consist of
12-14 foot wide 5sl slopes and 6 foot wide 1:1 slopes. There will also be
a 6 foot high sandstone wall at a 1/2:1 slope, left at the top with ade-
quate size rip-rap at the base of this wall.
The 5:1 slopes will have a surface layer of crushed sandstone and clay and
will be revegetated. If significant amounts of topsoil are encountered then
this topsoil should be salvaged for use as the surface layer in some of the
5:1 slopes. It will be very important during regrading to make sure the
rip-rap on the 1:1 slopes is of adequate size and is stable. In addition,
all regraded layers must be tied into each other well so no soil slippage
results.
At the end of mining, a 50 foot highwall approximately 100 feet wide will
be left at both ends. Slope of the highwalls will be 1/2:1. Blasting will
shear some rock off the face of this wall and deposit the rock at the
base of the highwall. This should prevent any erosion problems that might
result.
Seed-bed preparation, fertilizing, and seeding: After each atagv is
regraded, the top 3-5 inches of soil on the 5:1 slopes will need to be
roughened to alleviate compaction. This will increase water infiltration
and root penetration. Ater roughening the area, fertilizing will be done.
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