APPCOR12683

• Permit No: C1982055
• IBM Index Class Name: Application Correspondence
• Doc Date: 4/13/1982
• Doc Name: MEMO ANIMAS COAL MINE BENCH OVERBURDEN STORAGE AREA
• From: MLR
• To: BRIAN MUNSON
• Media Type: D
• Archive: No

DEPARTMENT OFtNATURAL RESOURCESn ~n .;,. r..,.•.~• III IIIIIIIIIIIII 111
D. Monte Pascoe, Executive Director 999
MINED LAND RECLA1~1:1'I'lON
423 Centennial Building. 1313 Sherman Street
Denver. Colorado 80203 Tel. [phone]
David C. Shelton
Director
M E M O RAN D U M
T0: Brian Munson, Sue Mowry
FROM: M,S. Savage
DATE: April 13, 1982
RE: Animas Coal Mine Bench/Overburden Storage Area
From my review of the permit application and my conversations t~itit Jim Pendleton
on this topic~Animas coal must meet the following requirements for mine bench
construction and overburden storage.
The applicant proposes to extend and/or fill certain portions of Che nets diverted
ephemeral drainage in order to facilitate construction of the mine bench and
provide for an overburden storage area. The applicant states at one point that a
large amount of the overburden material will be left in the gully to facilitate re-
grading and shaping of the post-mining surface. Several areas need to be addressed
for the Division to approve such a plan. The Division may approve placement of
excess material from underground mines where the placement does not meet the
requirements of approximate original contour if the applicant can demostrate that
the fill meets the requirements and performance standards of Rules 4.05 (Hydrologic
balance), 4.06 (Topsoil), 4.09 (Excess spoil), and 4.15 (Revegetation).with respect
With respect to the nature of the proposed bench and fill, there is a difference as
to whether it is designated as backfilling and grading or excess spoil. Backfilling
and grading of the bench material would require that the applicant meet the require-
ments of 4.14 and demonstrate that a minimum static safety factor of 1.3 has been
achieved.
For the overburden storage area, the applicant must demonstrate that this qualifies
as excess spoil. In addition, the pile must be designed and constructed according
to the requirements of 4.09, and is required to achieve a long term static safety
factory of 1.5.
As I understand it, the applicant has not determined the precise configuration of
the bench or overburden storage area. Fora technical evaluation, Jim Pendletion
shou}d be contacted.
MSS:ys