2014-07-07_REVISION - M2012032 ‎(16)‎

• Permit No: M2012032
• IBM Index Class Name: REVISION
• Doc Date: 7/7/2014
• Doc Name: Request for technical revision TR04
• From: Star Mine Operations
• To: DRMS
• Type & Sequence: TR4
• Email Name: RCO
• Media Type: D
• Archive: No

its own weight, plus the water circulation and the rotation of the drill bit. The combination of these
three observations, lead us the opinion that the bottom of the "second" aquifer was at the top of this
fine - grained soil material regardless of the location of bedrock. Therefore, well 3B was set with bottom
at 40 feet below grade. We performed a hydrometer analysis on some of the retained cuttings from 40
to 70 feet and found a -200 material content of 52.9% with the remainder being sand sized. The
laboratory gradation is attached. We note that the sand sized material was likely formed through
cutting action of the drill bit and that a portion of the finer - grained material (clay- sized) was lost in
suspension in the drilling fluid so the in -situ fines content would be expected to be greater than that
measured by the laboratory analysis.
A summary of pertinent monitor well details is presented in Table 1 below. The as -built graphic details
have been revised and presented on Sheet G -15 attached. The CDWR well completion reports are also
attached for your use and information.
TABLE 1- Monitor Well Summary Information
Well
Designation
Total Depth
from TOC
(ft)
TOC Stickup
above grade
(ft)
Total well
depth
(ft)
Ground
Elevation
(ft)
Water Level
below Grade
(ft) -
Water
Elevation
(ft)
GW -1A
8.13
3.2
4.93
10656.7
1.83
10654.87
GW -1B
17.06
3.86
13.2
10656.1
1.22
10654.88
GW -2A
14.4
4.03
10.37
10641.8
4.96
10636.84
GW -2B
28.84
4.23
24.61
10642
5.38
10636.62
GW -3A
16.1
3.73
12.37
10628.9
4.12
10624.78
GW -3B
42.65
3.51
39.14
10628.3
5.51
10622.79
Notes:
TOC= Top of 2 inch Casing (Marked at point of reference)
Total Well Depth is depth below ground surface at well location
Ground Elevations surveyed using Revenue Mine reference survey
Water Levels taken on 6 -12 -14 (one week after completion of all installations and prior to well development)
Water level elevations calculated from Ground Elevation
The wells were allowed to "stabilize" for about a week to allow some natural flushing of the drill water
used to install them prior to being developed and sampled. A minimum of three well volumes of water
was extracted for the development process. Based on the Water Elevation data in Column 7 above,
there may not be a true separation of a surficial and deeper aquifer at locations 1 and 2. We suggest
that the water levels (and water quality lab data) should be monitored closely in the future months to
see if there is an actual water table separation to evaluate whether or not to continue the shallow well
(GW -1A and GW -2A) sampling.
Revenue Mine TR -04 Appendix 15 Page 5