REP35439

• Permit No: C1981022
• IBM Index Class Name: Report
• Doc Date: 12/8/1999
• Doc Name: INTEROFFICE MEMO 1998 ANNUAL HYDROLOGIC MONITORING REPORT SANBORN CREEK MINE PN C-81-022
• From: MIKE BOULAY
• To: JOE DUDASH
• Permit Index Doc Type: STABILITY REPORT
• Media Type: D
• Archive: No

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1313 Sherman Sc, Room 215
Denver. Colorado 80203
Phone: [phone]
FAR: [phone]
STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
Deparimem of Natural Resources
INTEROFFICE MEMORANDUM
TO: Joe Dudash
FROM: Mike Boulay
DATE: December 8, 1999
SUBJECT: 1998 Annual Hydrologic Monitoring Report; Sanborn Creek Mine;
Permit No. C-81-022
999
DIVISION OF
MINERALS
GEOLOGY
RECLAMATION
MINING•SAFETY
R~II Owens
Governor
Greg E bValcher
E~P[ulrvc DireUOr
Michael 8. Lang
Drv~sion DveUar
I have reviewed the 1998 Annual Hydrology Report (AHR) for the Sanborn Creek Mine. The
operator did a good job in collecting and reporting the required water monitoring data in accordance
with the approved plan. Only minor deviations from the approved water monitoring plan are noted
for the frequency of data collection. Mine inflow was mapped and reported for 1998. It appears [hat
inflow has decreased in the "B" and "C" Seams from a total of 20l gallons per minute (GPM) in
1997 to 160 GPM in 1998. No new inflow locations were reported.
I have the following specific comments on the 1998 AHR.
1. The Table of Contents on page vi lists all of the monitoring data as 1997, this should be
changed to monitoring data for 1998.
2. On page 152, the report "Aquatic Impairment Study of the Sanborn Creek Mine Discharge,
Somerset, Colorado" is stated to be included in Section 6. This report was not included in the AHR.
If appropriate, please update the AHR to include a copy of this report.
3. There appeazs to be a significant increase in total dissolved solids (TDS) and conductivity
at surface water monitoring location S-2, immediately upstream of the North Fork of the Gunnison
River. Is this apparent increase the result of mine water discharge to Sanborn Creek? Please provide
a brief explanation of impacts, if any, to the North Fork as a result of this discharge.
4. The approved hydrologic monitoring plan requires that monthly field parameters be collected
for Springs #1-6 April through October. Monthly field parameters were not collected for any of
these springs in April. Please provide an explanation for the lack of data in April.