HomeMy WebLinkAbout01.01 Mining plan and timetableMINING PLAN AND TIMETABLE
exhibit 1V
EXHIBIT
MINING PLAN AND TIMETABLE
History
George Sievers, grandfather of the present owners of Sievers
Ranch, immigrated to the United States from Germany in 1880. In
1885 he came to the Roaring Fork Valley and acquired land four
miles down river from Carbondale. The raw land was cleared, and
a four and one-half mile irrigation ditch was built with picks and
shovels. The ranch became a successful operation producing
potatoes, hay, grain and livestock. George Sievers remained active
in farming until his health failed in 1920. The farm was tenanted
for many years. In 1952 George Sievers' daughter, Katherine Sievers
Holmes, and her husband, Harleigh Holmes Sr., formed Sievers Ranch &
Development Company, a Colorado corporation. This family-owned
corporation has continued to the present time as a farming opera-
tion raising grain, hay and cattle. Unlike most properties in
the Roaring Fork Valley, this ranch has been operated by the same
family for the past 94 years.
The approximately 122.95 acres included in this conversion
and amendment is the northeastern part of the ranch. The total
area of the ranch is approximately 625 acres. The northeastern
part of the ranch has extremely rocky soils and has been, at best,
very marginal grazing land.
In 1977 the family-owned Sievers Ranch & Development Company
filed for and obtained a limited impact permit (MLR file number
77 -98, anniversary date May 1, 1978) on 8.74 acres at the far
5
north end of the ranch property. The permitted property is leased
to a local firm which is responsible for the physical mining of
the property. While this is a rather unusual way for the land and
mineral owner to proceed, it was the most expeditious way for the
ranch company to exert control over the mining and reclamation
plans as well as the end product of those plans.
Current Conditions
Map Exhibit C shows the outline of the affected land, touching
landowners, topography and existing utility lines. Map Exhibit C-1
shows the outline of the affected land and current soil, vegetation
and hydrologic factors.
In the past the affected land has served only as very marginal
grazing land because of the rocky nature of the soil. For details
of current conditions see baseline data in Exhibits G, H, IN and K.
Mining Plan
Mining started on the north part of the area in 1978 under
MLRB Permit #77 -98. The 8.74 acres in Permit 77 -98 will be included
in this conversion as part of the total affected lands (see map
Exhibit C-1). A crusher operation now existing will continue to
be an integral part of the sand and gravel mining operation.
Mining will occur in 18 stages. When each stage is complete, a
reclamation phase will be started so as to minimize surface distur-
bance at any one time. The mining stages will begin at the location
of the present operation on the north end, will proceed easterly
6
EXHIBIT D (Cont'd)
and then in a southerly direction. Stage I is about three times
as large as any other stage because it was necessary to include all
of the limited impact permit land plus all land to the north that
is south of Robertson Ditch. Map Exhibit D -1 indicates the general
sequence and acreage in each stage. The contours on map Exhibit D-1
are drawn to show conditions at approximately the mid - -point of the
life of the mine. Map Exhibit F shows the final contour.
During the mining operations a berm will be created along
most of the north perimeter and all of the east perimeter of the
affected land by leaving part of the area unmined. This berm will
screen from view most of the visual impact that might occur from
this excavation. The 25 to 30 acres maximum that might be disturbed
at any one time is certainly much less than that caused by some
recent residential and recreational developments.
An excavation line set back from the affected land lines, a
distance that will vary between approximately 125 feet and 250 feet,
will create the screening berm that will be from 35 feet to 60 feet
high. See map D -1, mining stage XIV through XVII, for location of
the berm. Also see the sketch below for the approximate cross -
section of the berm.
TO BE MINED IN
STAGES I THRU XIII
CURRENT LAND.,,_U EA.
EXCAVATION
LINE
BERM TO BE MINED IN
STAGES XIV THRU XVII
35'••6
FINAL LAND SURFACE
- 7 -
6 -1
ROBERTSO
DITCH OR
ROARING
FORK
RIVER
~E,XH I B T - D—(Cant d 3
The pit will be operated year -round by lessees of the Sievers
Ranch & Development Company as an aggregate supply for himself and
for others. As operations begin on each stage, the soils will be
removed and stored for future use in seedbed preparation. The
acceptable soil varies from 12 to 48 inches with the average being
approximately 15 to 18 inches. There are places where there is no
soil and a few others where there is as much as 3 to 4 feet;
however, both of these are exceptions rather than the norm. For
details on soils please refer to Exhibit I /J. Soils lay directly
on the sand and gravel to be mined, there being no other over-
burden. The soils removed from the mining area will be stored on
lands that are part of present or future mining stages. Storage
areas will vary depending on location of each mining stage. A
cover, such as western wheatgrass, will be planted where necessary
to preserve the soil stockpile.
The sand and gravel below the soil on the affected land appears
to be in excess of 70 feet thick. Three attempts to drill test
holes encountered very dense gravels and cobble at depths ranging
from 10.5 to 14.5 feet. These materials were of such a nature that
further drilling became quite difficult. Diamond bits probably
would have penetrated the section, but this was not economically
feasible. See report by CTL /Thompson, Inc. in the appendix.
Inspection of the section along the river indicates a sand and
gravel section in excess of 70 feet at that location. Knowledge
of the gravels in the Roaring Fork Valley leads us to believe that
EXHIBIT. _.:D-- - - -(Co t-' d)
observed thicknesses will continue fairly well intact across the
land to be excavated.
The mining process will be carried on primarily by front-
end loaders. The loaders will unload to conveyors which will
carry the materials to the processing system. Mining equipment
may include, but is not limited to, front -end loaders, bulldozer,
dragline, water truck and dump trucks.
Each stage will be mined at two or three levels. The thick-
ness of each level may vary from 20 to 35 feet. Map D -1 shows
mining of the first six stages completed and mining operations on
the first level at Stage VII just being completed. In this Exhibit
Stages VII through P are shown as not being mined. For contours
after mining is completed, see map Exhibit F.
Exterior permanent slopes (perimeter) will be mined and
maintained at 3 to 1 so that final grading for reclamation will
be reduced to only seedbed preparation and revegetation. Likewise,
interior floors will be leveled to base grade as mining proceeds
so that only seedbed preparation and revegetation will be necessary
in the reclamation phases. Interior slopes are all temporary and
will be left at the angle of repose. One exception to the
interior slope being the angle of repose will be the interior
sides of the screening berm which will be excavated at 3 to 1
Robertson ditch runs along the north side of Stage I and
Stage XVII and along the east side of Stage XVI. The ditch
elevation is approximately 5,9:68 feet at the diversion point
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EXHIBIT D..-.(. Cont' d) ....:
on the Roaring Fork River and approximately 5,966 feet down -
stream at the last point where it adjoins Sievers Ranch property.
Plans for extraction of the sand and gravel will reduce the eleva-
tions on Sievers Ranch property to approximately a constant six
feet higher than the ditch. For instance, at the ditch diversion
from the river, Sievers Ranch land will have an elevation of 5,974
feet. Where the ditch leaves contact with the affected land, the
elevation will be approximately 5,972 feet (see map Exhibit F).
During excavation operations care will be taken to prevent any
damage to the Robertson ditch by earth - moving equipment or excavated
material. Since excavation will stop above the elevation of the
ditch, no loss of water from the ditch will occur. The Sievers
Ranch & Development Company owns approximately 9% of the Robertson
ditch.
The drainage of the affected land before mining is basically
from west to east and south to north toward the Roaring Fork (see
map Exhibit C). Because of the ditch system on the irrigated land
there are some reversals of the overall pattern, but these are
minor and are man-made in most cases. Drainage after excavation
is complete will have the same overall pattern as it did prior to
excavation. Specifically, the large drop in elevation will be
along the west side of the affected lands on a 3 to 1 slope rather
than a 1/2 to 1 slope at the river. The property along the river,
like that along Robertson ditch, will be excavated to elevations
that are 6 to 10 feet above the river bed. No significant change
in the drainage from its present condition is expected.
- 10 -
EXHIBIT ._..D.... {Copt -'• d).
Processing equipment may include, but is not limited to,
crushers, screens, screw washers, sand classifiers, trommel screens
and conveyors. The equipment will be operated in compliance with
air pollution standards. The current pit (MLR file number 77 -98)
is being operated under C.D.H. --Air Pollution Control Division- -
Emission Permit No. C- 11,539(FD) dated November 16, 1977. It is
expected that the pit will continue to be operated under this
permit. Part of Stage P (P indicates plant) will be used during
Stages II through XVII as the location of the scale house, sanitary
facilities, general yard and equipment storage. During Stage I
the scale house and sanitary facility will be left as they were
built for the original limited impact permit. The remaining part
of Stage P will be left undisturbed but will be used in the
acreage count as a floating disturbed area that will cover the many
location changes of the crusher system and stockpiles. For further
information, see the cost of reclamation estimate in Exhibit L.
The small amounts of water to be used in dust control and
plant operation are highly variable since operating days, windy
days, rained out, snowed out days and number of affected acres
fluctuate dramatically. These small amounts of water necessary
for dust control and plant operations are being supplied and will
continue to be supplied from waste water by the Sievers Ranch &
Development Company from water rights owned by that company. It
is not expected that any significant amounts of water will be
encountered during mining operations. There may be some minor
EXHIBIT D (Cont'd)
amounts of water in the sand and gravel during the period when the
fields on the upper part of the ranch are being irrigated. There
will be no discharge to the river by the mining or processing
operations. No NPDES permit will be required. See Exhibit G for
details.
Mining Timetable. The mining stages listed below may be
correlated to map Exhibit D -1. The stages correspond to the
reclamation phases in Exhibits E and F and are numbered accordingly.
Note that these are estimates only and that times may vary radi-
cally depending on market, weather and the general ecb,nofy.
Total
Mined Mined Acres
Stage Years Acres On Slope Total Acres
I 9 to 15 17.68 2.37 18.11
II 3 to 5 5.57 -0- 5.57
III 3 to 5 4.87 -0- 4.87
IV 3 to 5 6.48 3.38 6.90
V 3 to 5 6.22 -0- 6.22
VI 3 to 5 7.07 -0- 7.07
VII 3 to 5 6.49 -0- 6.49
VIII 3 to 5 5.43 -0- 5.71
IX 3 to 5 5.49 -0- 5.66
X 3 to 5 6.09 1.40 6.09
' XI 3 to 5 5.57 1.38 5.57
XII 3 to 5 5.70 2.07 5.70
XIII 3 to 5 6.85 4.77 6.85
XIV 3 to 5 6.13 3.32 6.13
XV 3 to 5 6.53 -0- 6.53
XVI 3 to 5 10.03 -0- 10.03
XVII 0.5 to 1.5 3.45 -0- 3.45
P 57 to 96 5.66 2.29 6.00
Totals 121.31 20.98 122.95