PERMFILE62241

• Permit No: C1981038
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Doc Name: Report of Subsidence Study ‎(6/83)‎ and Addendum
• Section_Exhibit Name: VOLUME 3- SUBSIDENCE STUDY
• Media Type: D
• Archive: No

is usual in exploration drilling, only limited attention was
• paid to the geologic conditions of the overburden of the D-
seam. The overburden was characterized by employing geo-
physical logs, spot core drilling and lithologic logging,
and retaining core samples for future study. Much additional
data on the geology of the area were obtained from other
publications dealing with the Mesaverde Formation in the
Paonia and Somerset mining district. CWI provided us with
additional data on physical properties of the coal seam and
on some of the overburden material.
Data on the hydrological conditions in the area are
also available Erom Dames & Ploore reports. Valuable in-
formation on hydrology was obtained from previous CWI worE:;
specifically, CWI 1982 annual hydrologic report and per-
tinent chapters of their 1983 mine permit application con-
tained valuable information that was used for the purpose of
the subsidence study. Data obtained from the above
referenced reports and studies were supplemented by field
inspections and by the general knowledge of hydrologic and
geologic conditions that were obtained during various
studies performed by GEO-HYDRO for CWI in the last three
years.
CWI geologists also provided valuable information
concerning the extent and interpretations of the faults that
• are present within the area and with the interpretations of
the lineaments in the proposed lease area.
Mining maps of the existing mine and the proposed
mining plan for the future lease were also made available.
The predicition of the subsidence within the lease is based
on these maps. Since the details of proposed mine plans are
constantly changing, the layouts shown on these plans should
be considered to be typical rather than final.
In order to supplement the information on geology and
other features that are important for subsidence, availahle
aerial photograohs have been carefully studied and the
future lease area has been inspected several times. The
purpose of these inspections ~;as to obtain additional data
on surface hydrology and to document several features that
are related either to landslides or the subsidence caused by
Wining within the present lease area. The scope of these
field inspections was also to review the available map of
'_andslides which was prepared by Junge (1978} and to verify
whether the interpretations of the landslides are correct.
lJe also feel that a careful documentation of the existing
subsidence cracks that dave]oped .hove the lst A'est panel
and the documentation of the landslides that were identified
•
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