REV09184

• Permit No: M1977342
• IBM Index Class Name: Revision
• Doc Date: 6/16/2004
• Doc Name: Tech Rev 15
• From: Climax Molybdenum Company
• To: DMG
• Type & Sequence: TR15
• Media Type: D
• Archive: No

© CLIMAX MOLYBDENUM COMPANY HENOERSON OaERAT1ONS
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Empire. Colorado 80436
[phone]
Fax (303J 569-2630
RECEIVED
June 10, 2004
Mr. Allen Sorenson JUN 16 2004
Colorado Division of Minerals and Geology Givision of Minerals & GeoloBY
1313 Sherman Street, Room 215
Denver, Colorado 80203
Re: Technical Revision No. 15 (Henderson Mine and Mill Permit M-77-342)
Dear Mr. Sorenson:
Climax Molybdenum Company, Henderson Mine and Mill (Henderson) requests consideration from the
Colorado Division of Minerals and Geology (DMG) for Technical Revision No. 7 S (TR-15) [o our mining
and reclamation permit (M-77-342). TR-15 would allow Henderson to dispose of dewatered high-density
water treatment sludge (HDS), generated at the Urad wastewater treatment plant (Urad), into the # I Dam
Tailing Impoundment located at the Henderson Mill (Mill). As required by DMG, please find two copies of
this submittal, along with a check to DMG in the amount of $875.00.
Introduction
In ] 996, Henderson constructed a water treatment facility at the site of the historic Urad Mine in the Woods
Creek Valley to collect, consolidate, and treat water from both the active Henderson underground mine and
the reclaimed Urad Mine. This treatment facility was commissioned in 1997, and has been successfully
treating process water since start-up. The treatment process generates approximately 3,000-4,000 cubic yards
of HDS annually. Historically, Henderson has disposed of the sludge at the BFI (nonhazardous waste)
landfill on Highway 93 in Jefferson County.
CMC submitted a Technical Revision (TR-8) [o DMG in June 1999 seeking approval from DMG to dispose
of the dewatered HDS in Pond 1.2 a[ the Henderson Mine (Mine) site. The TR was approved by DMG, with
the condition that approved measures be taken to protect the pond liner during placement of the sludge. Since
receiving approval for the TR, Henderson has identified potential logistical and cost issues associated with
using Pond 1.2 for this purpose. As a result of these issues, Henderson requests permission from DMG [o
dispose of the sludge in the Mill's #1 Dam Tailing Impoundment.
Sludge Characterization
HDS from the Henderson water treatment facility is very stable, alkaline, non-hazardous and non-toxic. It is
composed of precipitated metals and gypsum, contains no sulfides, and is highly inert. EPA's Toxicity
Characteristic Leach Procedure (TCLP) was performed on the sludge, with only barium being detected, well
below the regulated concentration. The pH was measured at 9.8. Additional detail regarding characteristics
of the sludge was provided to DMG as a part of TR-8.