REV17817

• Permit No: C1981041
• IBM Index Class Name: Revision
• Doc Date: 9/29/2000
• Doc Name: POWDERHORN COAL CO FINAL RECLAMATION DRAINAGE DESIGN - TR 034 ADEQUACY RESPONSE 1 PN C-81-041
• From: J E STOVER & ASSOCIATES
• To: DMG
• Type & Sequence: TR34
• Media Type: D
• Archive: No

. J. E. STOVER & ASSOCIATES
2768 COMPASS DRIVE, SUITE 101
GRAND JUNCTION, COLORADO 81506
PHONE: [phone], FAX [phone]
MINE ENGINEERING
MINE RECLAMATION
September 29, 2000
Dan T. Mathews
Division of Minerals and Geology
2148 Broadway, #C5
Grand Junction, CO 81503
Re: Powderhorn Coal Company
Final Reclamation Drainage Design - TR-034
Adequacy Response No. 1
Permit C-81-041
Dear Mr. Mathews:
III IIIIIIIIIIIIIIII
999
CIVIL ENGINEERING
CONST. MANAGEMENT
The DMG's letterdated September 19, 2000 transmitted its adequacy comments regarding
the referenced technical revision. The DMG approved the modeling demonstrations
indicating the proposed sediment controls will be adequate. The DMG requested the
appropriate reclamation maps be amended to depict the proposed silt fence locations and
locations of berms utilized to collect and direct run-off.
During a site visit on September 28, 2000, DMG, BLM and PCC personnel inspected the
2 west portals and came to the following conclusions:
1. All five culverts shown on Map 58 should be removed from the 2 west portal light
use road. Low water crossing are to be installed.
2. The temporary ephemeral stream channel relocation near the north 2 west portal
should be converted to a permanent ephemeral stream channel relocation.
3. The steep cut slope on a section or the road between the two portals should be
flattened. This will be accomplished by cutting the slope back about 10-feet into
undisturbed ground.
4. Reclaimed slopes should be rough to facilitate vegetation.
The stream channel relocation design is presented in Volume III, appendix 13-2, page Misc
-4. This diversion channel is designed to handle the 100-year event and the drainage area
is less than one square mile. The DMG should be able to make the necessary findings
under rule 4.05.3.
Maps 58 and SL-16-009 were revised to show the changes outlined above and to show the
silt fences and berms. Page 14-12 was amended to incorporate the minor clarifications
in the reclamation plan.