HYDRO22370

• Permit No: C1980006
• IBM Index Class Name: Hydrology
• Doc Date: 4/11/2007
• Doc Name: Groundwater Points of Compliance Memo
• From: Mike Boulay
• To: Dan Hernandez
• Permit Index Doc Type: Other Ground Water
• Media Type: D
• Archive: No

STATE OF COLORADO
DIVISION OF RECLAMATION, MINING AND SAFETY
Department of Natural Resources
1313 Sherman SL, Room 215
Denver, Colorado 80203 C O L O R A D O
DIVISION OF
Phone: [phone] INTEROFFICE MEMORANDUM RECLAMATION
FAX: [phone] M I N I N G
- &-
SAFETY
DATE: April 11,2007 Bill Ritter, lr.
Governor
TO: Dan Hernandez Harris D. Sherman
Executive Director
Ronald W. Canany
FROM: Mike Boulay Division DIfeCYOr
Natural Resource Trustee
RE: Marr Mine (Permit No. C-80-006)
Groundwater Points of Compliance
As requested, I have reviewed Tom Kaldenbach's geologic assessment of the Marr Mine
and Loadout regarding groundwater points of compliance, which is summarized in two e-
mails sent to me dated April 10, 2007 and attached at the end of this memorandum.
Based on the two a-mails and conversations with Tom, I believe that his assessment is
appropriate and with proper documentation, a groundwater point(s) of compliance would
not be necessary at the Marr Mine and Loadout. My review of Tom's assessment and
findings are provided below.
Based on my cursory review of available data, I believe that these sites do have the
potential to negatively impact groundwater, but this may be insignificant as discussed
below with regazd to allowable degradation, groundwater uses and classifications.
Information contained in the recent AHRs indicates limited exceedances of the Basic
Standards for Ground Water for certain constituents at some well locations. However,
the WQCC recognizes that mining activities occur within ground water bodies and that
water quality within the disturbed area will obviously change. The point(s) of
compliance established outside the area anticipated to be disturbed may protect the water
body while allowing the mining activity. (The Basic Standards for Ground Water section
41.12 page 29.) For this reason, water quality from ground water monitoring well
locations within or in close proximity to the disturbance area(s) may not meet compliance
with the applicable standards. Some degradation of groundwater is allowed by
Regulation No. 41. However, compliance with ground water standards must be achieved
at the point(s) of compliance.
Groundwater points of compliance may not be necessazy at the Marr Mine and Loadout
based on the "Limited Use and Quality" argument and whether or not the groundwater
within the specified area impacted by the mining activity is used or is reasonably
expected to be used in the future. Based on the a-mail correspondence from Tom, points
of compliance will not be needed at the Marr Mine or Marr Loadout based on the
following. At the mine site, the pit is in the bottom of a syncline; therefore, plume
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