2011-04-26_REVISION - M1978210 ‎(3)‎

• Permit No: M1978210
• IBM Index Class Name: REVISION
• Doc Date: 4/26/2011
• Doc Name: Comments
• From: Weld County
• To: DRMS
• Type & Sequence: AM4
• Email Name: MAC
• Media Type: D
• Archive: No

EXHIBIT D - Mining Plan
a) Mining Schedule - Mining began on the Geisert site in 1979 and is nearly complete. Stockpiles of
processed materials are anticipated to be stored onsite in the east stockpile area through 2012. In the future, the
stockpile area will continue to be utilized by Weld County to stockpile gravel, riprap, fencing, etc for use on Weld
County roads.
b) Topsoil thicknesses at the Geisert site were thin, typically less than 6 (six) inches. Limited topsoil
has been stockpiled at the site, the County has the ability to make or import additional topsoil should it be needed
for reclamation of the surface areas.
C) The gravel deposits at the Geisert site are alluvial stream channel deposits associated with the
Cache La Poudre River. Minimal stockpiling of overburden has been needed; the waste materials were utilized as
generic fill by the County for County road construction projects.
d) The estimated thickness of gravel-bearing zones varied from between 20 and 60 feet thick at the
Geisert site.
e) The enclosed Site and Mining Plan Map (Exhibit C) shows the current configuration of the existing
gravel pits, reclaimed areas, mitigation wetland, and access road for the Geisert pit. Gravel processing (crusher and
screen locations), and soil and gravel product stockpile areas are located at the east end of the site.
f) The entire Geisert site encompasses 99 acres. The area proposed for slurry wall installation
encompasses the two existing ponds with an area of 54.3 surface acres.
g) The gravel excavation, processing and stockpiling areas are accessed from H Street, Greeley.
h) There are surface water impoundments directly north of the Geisert East and West pits proposed
for slurry wall installation.
The "L-shaped" pond (Area B) is a mitigation wetland constructed from a mined out area by Weld
County at the direction of the U.S. Army Corps of Engineers. Release of this Area B mitigation area
(26.57) is requested.
The adjacent Hiner gravel pit, still under DRMS permit #M-1977-151. It is privately owned and is
currently utilized as a recreational "ski" lake.
Water for dust control at the Geisert site has been obtained from a County-owned well located at the
west end of the mining permit area. The Geisert dust control well is covered under a Substitute Supply
Plan with the State Engineer's Office.
i) The existing Geisert gravel pits intersect groundwater. The adjacent Hiner pit intersects ground
water. The Geisert pits proposed for slurry wall lining are also in hydraulic communication with the Cache La
Poudre River. The Geisert site does not lie in a Designated Ground Water basin (per Colorado Division of Water
Resources, Office of the State Engineer).
D It is anticipated that slurry wall installation at the Geisert site will not disturb surface water or
ground water quality. Erosion control measures (Best Management Practices) will be installed along the perimeter
of disturbed areas to protect the adjacent areas runoff and sediment during slurry wall installation.
k) Any onsite generated trash will be collected and disposed at the adjacent County Public Works
facilities. No chemicals are anticipated to be utilized at the site.
1) Best Management Practices, including berms, silt fencing, and straw bales erosion control
measures will be installed along the perimeter of the Geisert slurry wall site to prevent release of mined area runoff
WDAVE B\Geisert Pit\DRMS Permit Amendment\Geisert Amendment Application & Exhibits Revised 4-21-11.docx