APPCOR12840

• Permit No: C1981032
• IBM Index Class Name: Application Correspondence
• Doc Date: 7/18/1980
• Doc Name: RIENAU 2 COAL APPLICATION FOR SUB MAIN EXTENSION BENEATH CURTIS CREEK
• From: MLR
• To: FRED BANTA
• Media Type: D
• Archive: No

STATE OF COLORnpO 9iC HARD D LAMM. Gnv ~•~n n. III IIIIII 111IIII III
DEPARTMENT OF NATURAL RESOU RCES
Harris D Sherman. Execute ve Duector gyy
M1NED LAND RECLAMA'T'ION
723 Centennial Building, 1313 Sherman Street
Denver, Colorado 80203 Tel. [phone]
Hamlet J. Barry, III,
Director
July 18, 1980
TO: Fred Banta
FROM: Jim Pendleton
RE: Rienau No. 2 Coal's Application for Sub-Main Extension Beneath ~
Curtis Creek
1 have reviewed Northern Coal Company's hydrology report concerning the
Rienau No. 2 coal mine, and their subsequent response to our request for
additional information. I forward the following comments for your
consideration in this matter.
The applicant's interpretation concludes that, based on their analysis,
no significant subsidence or related hydrological impacts will occur.
Unfortunately their data collection techniques were not as definitive as
they might have been and some topics remain unresolved.
Of particular concern is the potential subsidence of Curtis eek as a
result of proposed mining beneath the valley floor. in valleys
such as that of Curtis Creek, tend to develop preferentially in~more easily
eroded zones. In situations in which such a creek crosses perpendicular
to formation outcrop, or strike, the zone of easiest erosion is often a
fracture or fault lineament. If this were the case for the Rienau No. 2
permit area, it could have distinct implications for their mine plan. The
presence of concentrated fracturing for faulting beneath the creek valley
floor could cause undesireable subsidence and infiltration.
At your request 1 contacted Jim Shaeffer, a geologist on Northern Coal's
staff, yesterday, to discuss this specific concern. I indicated to Mr.
Shaeffer that their application would have to be amended to include a r
discussion of the lineament topic, including its ,h&ture and implications'y
for their proposed activity. I suggested the utilization of all existing
possible boring data, field mapping and specifically air photo resources.
E..
2 also indicated to Mr. Shaeffer that we were considering approval of their
request to be allowed to drive access sub-mains beneath Curtis Creek. I
discussed our belief that properly conducted and monitored excavation of
one sub-main could serve as a test case to determine rock quality, an
(cont'd)