GENERAL56249

• Permit No: M1977342
• IBM Index Class Name: General Documents
• Doc Date: 8/3/1994
• Doc Name: NOTICE OF DETERMINATION AS A DESIGNATED MINING OPERATION HENDERSON MINE PN M-77-342
• From: DMG
• To: CLIMAX MOLY CO
• Media Type: D
• Archive: No

DIVISION OF MINERALS AND GEOLOGY
Deparimenl of Natural Resources
1313 Sherman Si., Room 215
Denver, Colorado 80203
Phone: [phone]
FA%:[phone]
August 3, 1994

STATE OF COLORADO
II~
DEPARTMENT OF
NATURAL
RESOURCES
Mr. Jay Jones
Climax Molybdenum Company
P.O. Box 68
Empire, CO 80438
RE: Notice of Determination as a
Ruy Rnmr~
Govvmo~
Ken Sa laav
Exe[ulrvr Dnedur
KLChacl tl. Long
Donlon Direcmr
Designated Mining Operation,
Henderson M1ne, Permit No. M-77-342
Dear Mr. Jones:
As a result of review by the Office of Mined Land Reclamation of your
permit application, pertinent geology and geochemistry and recent
inspection reports, you are hereby notified, pursuant to Ru:Le 7.2 of the
Mineral Rules and Regulations of the Colorado Mined Land Reclamation
Board, that the Henderson Mine, Permit No. M-77-342, has been determined
by the Office to be a Designated Mining Operation for the following
reasons:
1) Designated chemicals used in metallurgical processing are
present onsite. Such designated chemicals include sodium cyanide
and sulfuric acid used at the mill site. Sodium hydroxide is used
at the mine site for water treatment. Other chemicals in use at
the mine and mill may also be designated chemicals. Part of the
Environmental Protection Plan required for Designated Mining
Operations will be specification of chemicals at the site, an
assessment of their potential adverse environmental impacts, and
description of measures taken to prevent such impact::.
2) Toxic- or acid-forming materials are or will be exposed or
disturbed as a result of mining operations. Pyrite and other
metal sulfides are endemic to the Henderson ore body. These
potentially acid and heavy metal generating minerals are depressed
in the milling process and are discharged to permanent disposal in
the tailing impoundment.
3) Acid mine drainage occurs or has the potential to occur due to
mining or reclamation activities. Currently, groundwater from the
underground workings of the Henderson Mine is pumped, treated and
discharged in accordance with your CDPS permit. Prior to
treatment, the mine water would meet the definition of acid mine
drainage contained within the Mineral Rules and Regulations.
Currently, mill water is continuously recirculated, and the