2010-08-27_REPORT - M1983194

• Permit No: M1983194
• IBM Index Class Name: REPORT
• Doc Date: 8/27/2010
• Doc Name: Elevated Conductivity
• From: Daub & Associates, Inc.
• To: DRMS
• Email Name: THM
• Media Type: D
• Archive: No

Notes on Tables and Figures
Table 1: BG-5 field sampling results and events and Figure 2: BG-5 field and lab conductivity comparison
indicate an abnormally low field conductivity reading which was attributed to a miscalibrated meter, the
well was resampled following recalibration with near baseline results obtained.
Table 2: BG-5 ACZ analytical data, charted parameters only and Figure 6: BG-5 calcium, magnesium,
potassium and silica indicate an abnormally high potassium level in the August 2"d sample. The well was
resampled by NSI on August 9`h and analyzed by ACZ, the potassium from the August 9`h sample was
reported at 4.76 mg/L.
Research of BG-5 Groundwater Conductivity Anomaly
A due-diligent research effort was performed in an effort understand the anomaly and/or rule out other
potential causes. The following items were considered in this research effort while analyzing the potential
for contribution to the noted anomaly:
1. BG-5 was not fully developed.
Considered a plausible and most likely factor. Due to equipment constraints, a limited volume of
water was purged from the BG-5. Drilling fluids, Lost Circulation Material (LCM), high saline
groundwater from the Dissolution Surface Aquifer and/or cement displacement fluids may have
impacted the localized near bore hole ground water allowing some residual fluids to remain in the
B-Groove Aquifer near the well bore.
2. Problems with BG-5 sampling procedure or equipment.
Considered a possible factor but not likely. Water level monitoring indicate no abnormal
conditions. The water level fluctuated only 2 feet from 522.8 to 520.8 from March 10 to August
16, 2010.
3. BG-5 plug back and completion.
Not considered a factor. Completion records, cement reports and cement bond logs indicate that
the well was properly plugged and completed. The underlying Dissolution Surface and overlying
A-Groove Aquifers appear to be correctly sealed from the B-Groove Aquifer.
4. BG-5 cement plug or casing cement is contaminating samples.
Not considered a factor. Laboratory pH results for all groundwater samples collected to date
range from 9.3 to 9.5. These values are consistent with those found in the BG-1 and BG-4 wells.
5. 1OH-I and/or 11H-I mining operations impacting BG-5 samples.
Not likely. Mining operation parameters have remained stable for all of 2010. No pressure or
pumping anomalies have been noted in any of the NSI plant production monitoring data. In
addition, water levels in the BG-5 have remained constant.
6. Oil and Gas wells impacting BG-5 samples.
Not likely. The only oil and gas wells upgradient of the BG-5 are the Williams wells located in
section 36. These wells were drilled between 2007 and 2008.
7. Drilling of 2010 coreholes impacting BG-5 samples.
Not likely. The 2010 drilling and coring program began in July, 2010. This date is after the BG-5
anomalous sample results.
Daub & Associates, Inc. BG-5 GW Sampling Anomaly 8-24-10 rgd
Printed: 8/24/2010 Page 14 of 15