2014-10-29_REVISION - M1998013

• Permit No: M1998013
• IBM Index Class Name: Revision
• Doc Date: 10/29/2014
• Doc Name: TR-2 Review Comments
• From: Civil Resources, LLC
• To: DRMS
• Type & Sequence: TR2
• Email Name: ECS
• Media Type: D
• Archive: No

Burch Technical Revision 2 Review Comments
October 29,2014
Page 2 of 2
West Cell East Cell North Cell Total
cy) (Cy) (c ) (c )
Overburden 135,040 104,039 15,242 254,321
Backfill Req. 212,206 218,716 0 430,922
Gravel 173,623 166,461 0 340,084
Fines 31,252 29,963 0 61,215
4)DRMS will require Bestway to commit that topsoil be salvaged from the Burch Parcel to used in site reclamation.
Bestway will generate a letter stating they will leave 430,922 cubic yards of material onsite.
5)Please show on the map submitted where the stockpiled overburden and topsoil to be used in the proposed backfill
reclamation will be placed.
The stockpiled backfill material will be placed on either the east or west un-mined cell,around the perimeter or
on the area to the south as shown on the attached figure. Approximately 12 acres would be required to
stockpile the available overburden(300,000 cubic yards, not including fines generated from washing)at 15 feet
high. There is 10 acres available in the southern portion and either 14 to 9.4 acres available on the Burch Site
during mining. Bestway intends to use as much of the Burch site to stockpile and they will backfill once a
mining cell has been completed.
6)Does Bestway still intend to reclaim this area as developed water storage? If so, at what point in the mining plan
does Bestway intend to install/test the slurry wall?
Bestway intends to backfill the east cell but the west cell might be backfilled with clayey overburden and leak
tested 1.5 years after the start of mining.
7)Bestway still has not submitted a groundwater monitoring plan for DRMS review and approve prior to the exposure of
groundwater in the Burch parcel as required in the approval of AM02.
See attached groundwater monitoring plan.
8)Bestway will need to provide signed damage waiver agreements with all structure owners within 200'of mining activity
in the Burch parcel(Weld County, Last Chance Ditch, Rural Ditch, anadarko)that are not yet on file, or if they cannot be
obtained,provide geotechnical assessments that will confirm that the proposed activities will have no adverse impact on
these structures.
An extensive slope stability analysis was performed for the prior amendment assuming a slurry wall would be
constructed. The slurry wall is a weaker material,which was modeled with zero strength that has now been
removed,and all of the setbacks have been matched per that initial analysis.Therefore this is now a more
conservative layout. See the attached slope stability figure to confirm matching setbacks with the new layout.
323 FIFTH STREET•FREDERICK, COLORADO 80530. PHONE:[phone]• FAX:[phone]