REP21825

• Permit No: C1981018
• IBM Index Class Name: Report
• Doc Date: 6/9/2000
• Doc Name: 1999 AHR & CORRESPONDENCE
• From: MULTIPLE PARTIES
• Annual Report Year: 1999
• Permit Index Doc Type: HYDROLOGY REPORT
• Media Type: D
• Archive: No

STATE OF COLQRADO
DIVISION OF MINERALS AND GEOLOGY
Depanmenl o(Nawral Resources
1313 Sherman 51., Room 215
Denver, Colorado 80203 D I v 15 l O N O F
Phone: [phone] :r MINERAL S
FAX: [phone] $c
GEOLOGY
RECLAMATION
MINING•SAFETY
INTERNAL MEMO Bill Owens
Governor
Greg E. Walc her
Esecutrve Director
M¢hael B. Long
TO: Dan Mathews ~ 26 May 2000 Divrsion Director
FROM: Jim Bumel• ~.
SUBJ: 1999 Annual Hydrology Report for Deserado Mine
1 completed a review of the 1999 AHR for the Deserado Mine. Deserado's monitoring
requirements have been decreased considerably in recent years because of the dry conditions at
the mine site. TR 47 discontinued the surface water monitoring program in 1997 because there
was virtually no surface water and monitoring was essentially meaningless. Also, the frequency
of monitoring for bedrock groundwater wells was decreased last year. Alluvial groundwater
monitoring was greatly decreased by the recent innundation of five of the six wells by the filling
of a local reservoir, and monitoring of alluvial groundwater in Red Wash was discontinued
several years ago because the objective of the program was attained.
In general, the water level in wells a mile or more away from active mining have remained
stable. A review of the water level measurements on remaining bedrock groundwater wells
don't display any real consistency, except for the fact that they have displayed more variability
than wells farther away and the shallow wells have displayed less fluctuation of water level than
the deeper wells.
Regarding water quality, the alluvial groundwater is of poor quality. This has been noted in
previous yeazs. The Hydrology Task Force has recently suggested that all mines analyze for
constituents for which a receiving stream standard exists. This applies to discharges or affected
water that will flow into the stream in question. It is not clear how Deserado is affected.
NPDES discharges which reach the White River should be analyzed for a variety of constituents
not currently within the monitoring plan. However, we need to discuss which, if any, of these
discharge points may ever discharge into the river and how much water would be involved
before any suggestions are made.
As of now, the predictions contained within the Probable Hydrologic Consequences section of
the permit are borne out and there appears to be no impact from mining on either surface water
or groundwater in the area of the Deserado Mine.