DRC-2009-003304 - 0901a0688012e217

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Department of
Environmental Quality
Amanda Smith
Acting Executive Director
DIVISION OF RADIATION CONTROL
Dane L. Finerfrock
Director
State of Utah
JON M. HUNTSMAN, JR.
Governor
GARY HERBERT
Lieutenant Governor
August 6, 2009
CERTIFIED MAIL
RETURN RECEIPT REOUESTED
Mr. David C. Frydenlund
Vice President and General Counsel
Denison Mines (USA) Corp. (DUSA)
1050 Seventeenth Street, Suite 950
Denver, CO 80265
Subject: November 12, 2008 DUSA Request for Relaxation of Accelerated Monitoring Schedule For
Certain Wells - State of Utah Groundwater Discharge Permit No. UW370004
Dear Mr. Frydenlund:
On November 12, 2008 DUSA submitted a request for relaxation of certain groundwater parameters in
accelerated monitoring status. These included the following wells and parameters:
• MW-5: Tetrahydrofuran
• MW-19: Selenium
The GWCL for THF in MW-5 is 11.5 fig/L. DUSA first exceeded this GWCL during the 4* Quarter, 2005
monitoring event with a result of 13 jttg/L. The sample collected during the 1^' Quarter, 2006 monitoring
event began 13 consecutive samples with THF concentrations below the GWCL.
The GWCL for selenium in MW-19 is 12.5 ^g/L. DUSA first exceeded this GWCL during the 2"" Quarter,
2005 monitoring event with a result of 18 /xg/L. The sample collected during the 2°'^ Quarter, 2006
monitoring event began 12 consecutive samples with selenium concentrations below the GWCL
Because these wells had parameters with one initial concentration exceeding their respective GWCL (Table
2 of the Permit) followed by multiple consecutive samples with concentrations that are below the
respective GWCL, we agree that the parameters can be relaxed from accelerated quarterly to semi-annually
monitoring for tetrahydrofuran in well MW-5 and relaxed from quarterly to semi-annually monitoring for
selenium in well MW-19.
Thank you for your continued cooperation. Please contact Phil Goble at [phone] with any
questions.
168 North 1950 West • Salt Lake City, UT
Mailing Address: P.O. Box 144850 • Salt Lake City, UT 84114-4850
Telephone [phone] • Fax [phone] • T.D.D. (801) 536^1414
wiini'.deq.ulali.gov
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UTAH WATER QUALITY BOARD
Dane L. Finerfrcwk,
Co-Executive Secretary
DLF/PRG:prg