2004-10-01_REVISION - M1997054

• Permit No: M1997054
• IBM Index Class Name: Revision
• Doc Date: 10/1/2004
• Doc Name: Technical Revision
• From: Applegate Group Inc
• To: DMG
• Type & Sequence: TR5
• Media Type: D
• Archive: No

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Applegate;
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September 30, 2004
Colorado Department of Natural Resoyrces
Division of Minerals and Geology /
Attn: Mr. Larry Oehler
13"13 Sherman Street; Room 215
Denver CO, 80203
RE: Technical Revision for Front Range Aggregates, LLC
Parkdale Quarry, M-1997-054 ~
Dear Mr. Oehler:

SCI 0 ~ 2004 ~
Division of lelinorals & Geology
On behalf of our client, Front Range Aggregates, LLC, please accept the following information for a
technical revision on reclamation permit M-1997-054, Parkdale Quarry. This technical revision
specifically covers operation of the site processing facility. The crushing, screening, and washing
components are currently covered in the existing reclamation permit, but specific aspects of the wash
water process have changed.
The current reclamation plan includes the washing component of the processing facility, with water being
pumped directly from the Arkansas River and disposal of process fines on-site. The process would
include withdrawal of fresh water from the river, product washing, cyclone treatment of the process water
to remove suspended fines, and reuse or discharge of the treated water. During the cyclone treatment,
process fines would be thickened to reduce the moisture content and then the fines would be placed in
trenches on-site.
The new wash water process includes reuse of all process water from the facility. Water from the
processing facility will be circulated through a series of sedimentation ponds to allow suspended fines to
settle from the wash water. Following circulation through the sedimentation ponds, the process water will
be reused as wash water in the processing facility. Fresh water to replace evaporative losses from the
system will be withdrawn from an alluvial groundwater well on-site. Withdrawal from the.alluvial well
and evaporative losses from the settling ponds will be covered with a well permit and Substitute Water
Supply Plan approved by the State Engineer's Office.
The settling ponds will be excavated in the bottom of the existing alluvial" sand and gravel pit (see
Technical Revision Plan -Site Map): Typically, there will be three (3) ponds, covering approximately
0.5 acres. To circulate process wash water, the ponds will be joined in a series, with flow exiting one
pond and entering another. Water will enter the first pond from the processing facility, and return to the
processing facility after exiting the last pond in [he series. As the ponds fill with sediment, new ponds
will be created and the old ponds will be backfilled.' Alternatively, sediment may be removed from the
operating ponds, allowed to dry, and used as backfill on-site.
Since the pit bottom is already near the normal alluvial groundwater table, the ponds will be excavated
into the groundwater. Groundwater that initially fills the ponds will be pumped to the processing facility
1499 West 120th Avenue, Suite 200 [phone] • Fax [phone]
Denver, Colorado 80234-2759 www.applegategroup.com