GENERAL54164

• Permit No: M1980244
• IBM Index Class Name: General Documents
• Doc Date: 11/1/1994
• Doc Name: RECOMMENDATION OF RECISION OF APPROVAL FOR DRAIN COVER MATERIAL SIZE GRADATION CHANGE CRESSON HEAP L
• From: DMG
• To: BRUCE HUMPHRIES
• Media Type: D
• Archive: No

• • iii iiiiiiiiiiiuiii
999
STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
Depanmenl of Natural Resources
1713 Sherman 51., Room 215
Denver, Colorado 80203
Phone: [phone]
FAX:[phone]
DATE: November 1, 1994
TO: Bruce Humphries
FROM: Jim Pendleton
Urb~!~
DEPARTMENT OF
NATURAL
RESOURCES
Roy Romer
Governor
lames 5. Lochhead
Executive Director
Michael B. Long
Division Director
RE: Recommen ti ecision of Approval for Drain Cover
Material Size Gradation Change - Cresson Heap Leach Pad
(Permit No: M-SO-244)
Last evening, October 31, 1994, at approximately 6:00 pm, I
received and read a copy of Gary Curtiss' 10/21-24/94 Cresson Mine
inspection report. In that document Gary relates having observed
CC&VG's Contractor placing drain cover material with neither Ames
laborers nor Golder CQA personnel present, on the morning of
October 23rd, 1994. This is in direct disregard of the "Drain
Cover Fill Placement Procedure" recommended by Terry Manziak of
Golder Associates Inc. in a memorandum to Bateman Engineering on
October 11, 1994 (see attached).
On October 7, 1994, CC&VG requested a modification to
gradation specifications for placement of drain cover
outside the "Pregnant Solution Storage Area" of the Phase
Leach Pad. Gradation tests performed on the Pad #2 source
had determined that it would not meet the size gradation
contained within the original specifications (minus 1").
one of the eight tests performed had failed to meet the
specifications for the drain cover material
the "Pregnant Solution Storage Area" (minus
the size
material
One Heap
material
criteria
In fact,
original
specified for use in
1.5").
During the discussions which ensued, I voiced reservations
regarding the modification. After several exchanges I agreed to
recommend approval of the specifications with two conditions:
(1) The originally specified certification testing frequency be
accelerated to once daily (rather than every 20,000 cubic yards);
and (2), the operator implement a visual monitoring and control
procedure to ensure that oversize material would be removed from
the drain cover material as it was placed (see attached memo).
As I discussed with you, Carl Mount, Mike Long, CC&VG personnel and
Golder's representatives, no characterization process is foolproof.