REV96128

• Permit No: C1980006
• IBM Index Class Name: Revision
• Doc Date: 3/13/1990
• Doc Name: MIDTERM RESPONSES RECEIVED JANUARY 26 1990 KCC MARR MINE PN C-80-006
• From: MLRD
• To: CATHY BEGEJ
• Type & Sequence: MT2
• Media Type: D
• Archive: No

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STATE OF CIII Illllllll~ly
MINED LAND RECLAMATION DIVISION
Department of Natural Resources
1313 Sherman St.. Room 215
Denver. CO 80203
303 866-366'
Fax [phone]
DATE: March 13, 1990
TU: Cathy Begej
FROM: Carl Mount ~~ ~~'`~~
kE: Midterm kesponses Received January 26, 1990,
Kerr Coal Company (KCC) Marr Mine, Permit C-80-006
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Roy Romer,
Govemo~
Fretl R. Barra.
Dwis~on Dueaor
I have reviewed KCC's response to ML RD question 3 from the Midterm Review
tlated March 16, 1989 and follow up on question 3 contained in the MLRD letter
dated November 9, 1989. Apparently, drill hole identification was mixed up in
my initial review (see memo from Carl Mount to Cathy Begej of
October 26, 1989). I inadvertently thought that drill holes 028-19-12 and
U28-79-14C in the Pit 3 area were sampled and that the results were presented
on Table 73a - Overburden Analysis Forms. This is not the case. Instead,
Table 73a presents data from drill holes 028-77-12C and 028-77-14C located in
the 720 Pit area. With this oversight on my part in mind, the following
comments address KCC's answers in the same order as they are presented:
Sodium Adsorption Ratio (SAR) Values - Pit 2 Area
KCC claims that the high SAR value of 25.2 in a sample collected on 10-8-80
from Drilihole No. 028-80-28C is a result of contamination by drilling fl uid.
No supporting analyses of the drilling fluid were included so it is impossible
to say whether the samples were contaminated ana to what degree they were
contaminated. It is interesting to note that samples collected on 10-31-80
showed SAR values of 3.3, 16.9, and 9.6. The 16.9 value was obtained from the
same sampling interval as the previous 25.2 value. KCC goes on to state that
"...corresponding data collected from other drillnoles (028-80-021C,
028-80-23C and 028-8U-24C) which intersected the same geologic strata support
t'r~e contamination argument." This statement is only partially true in that
drillhole 028-80-23C is the only hole that intersects similar geologic
strata. When SAR values are compared in the same geologic strata, these
values are relatively high (12.9) and show the same general trends as
Drillnole No. 028-80-28C. The sample from 028-80-23C was composited over 118
feet so the compositing may mask high SAR values of any one zone. Drillhole
028-80-23C was drilled using no drilling fluid so samples should not have been
contaminated.