APPCOR13049

• Permit No: C1994082
• IBM Index Class Name: Application Correspondence
• Doc Date: 1/13/1995
• Doc Name: PRELIMINARY ADEQUACY CONCERNS YOAST MINE C-94-082 PERMIT APPLICATION
• From: DMG
• To: SUSAN L BURGMAIER
• Media Type: D
• Archive: No

10) Appendix 7-3: Aquifer Tests
a) Original water levels are not recorded.
b) Explanation of negative drawdowns is needed.
c) From the data sheets, it appears that the
observation wells were located less than one
foot from the pumping wells. Please explain.
d) it is not clear which wells were pump ing wells
and which were observation wells.
Tab 15: Hvdroloaic Monitoring Program
11) Page 19 (Table 15-7): It does not appear that PWCC
intends to include the first aquifer below the coal seam
to be mined in its ground water monitoring plan. The
first aquifer below the coal seam to be mined (presumably
the Trout Creek Sandstone) should be included in the
ground water monitoring plan to detect potential impacts.
12) Page 21: PWCC proposes discontinuing monitoring of
groundwater in the Wolf Creek Underburden. However, one
pit will be located in the Wolf Creek Coal, and the
groundwater in the Wolf Creek Underburden has a potential
for impact. Therefore, groundwater monitoring in the
Wolf Creek Underburden should resume prior to mining the
Wolf Creek Coal.
Tab 16 Protection of the Hydrologic Balance
13) Attachment 16-1: Water Rights Investigation and Plan for
Augmentation is missing.
Tab 17: Probable Hvdroloaic Consequences
14) Page 31: PWCC should elaborate on their arrival at a
peak TDS concentration for the spoil discharge. The
discussion should include a description of chemical
reactions in the unsaturated zone (where the lysimeter
samples were collected) and how that compares with
conditions expected within the spoil aquifer. This is a
critical point, as all of PWCC's subsequent calculations
of salt loading to the aquifers and surfacg water bodies
are based on the assumption that 4500 mg/1 is a
conservative estimate of spoil water discharge quality.
15) The PHC predicts impacts only for the first 5 years of
.mining. Impacts predictions for the life of the mine
should be included.
16) Page 15: The average pit inflow of 11,254 gpm for the
Wadge Coal and Overburden doesn't seem to agree with the
inflow values presented in Table 17-2. Please explain
the discrepancy.