DRC-2010-002848 - 0901a06880186d6b

DENISON
MINES
10-00 28
Denison Min«s (USA) Corp.
1050 17th Street, Suite 950
Denver, CO 80265
USA
Tel: [phone]
Fax: [phone]
www.denisoninines.coin
April 23, 2010
VIA OVERNIGHT DELIVERY AND E-MAIL
Mr. Dain L. Finerfrock
Executive Secretary
Utah Radiation Control Board
Department of Environmental Quality
168 North 1950 West
P.O. Box 144810
Salt Lake City, Utah 84114-4810
Re: Denison Mines (USA) Corp.
September 30, 2009 Annual Technical Evaluation of the White Mesa Mill Tailings Management System
Blanding, Utah
Utah Radioactive Material License No. UT 1900479
Request for Additional Information
Dear Mr. Finerfrock:
Denison Mines (USA) Corp. ("Denison") is providing the follow responses to the February 25, 2009[10] Request
for Information from the Division of Radiation Control ("DRC"). Each DRC request is shown in italics below,
followed by Denison's response to the question and/or request for information.
1. Settlement Monitoring.
In a DUSA Letter dated December 30, 2008 regarding the 2007-2008 A TER,
DUS A stated, "Ttie ATER recommended the new settlement monitoring to the
Mill's Management and they have committed that the new monitors, where
needed, will be installed and surveyed as to location by no later than June 30,
7009." It appears the new monitors correspond to the proposed settlement
monitor 2W5-s for Cell 2, and other additional new monitors for the areas recently
covered in Cell 3.
In this regard, the DRC closeout letter for the 2007-2008 ATER dated April 23,
2009 states, 'Confirmation of this work must be documented in the 2009 ATER
Report. The designated, names of the new settlement monitors locations will
need to be unique, coordinated and updated to be in agreement on various maps
and forms, in future Annual Technical Evaluation Reports (ATERs) as well as the
DMT Monitoring Plan. Please revise these documents as appropriate for submittal
in the 2009 A TER Report."
Confirmation of this work was not submitted in the subject September 30, 2009
ATER. Please submit the required confirmation of the new settlement monitor
installation work with corresponding settlement survey tables and graphs.
Letter to Dane L. Finerfrock
April 23, 2010
Page 2
No additional Settlement Monitors on Cell 2 or Cell 3 had been installed at the time of the 2009 ATER.
Subsequent to the 2009 ATER, Settlement Monitor 2W5-S has been installed. The Settlement Monitor map will
be updated for the 2010 ATER and the monitoring data will be included in the report.
6. In the subject DRC approval letter dated April 23, 2009 we state, "Our previous
comment letters . . . have requested that DUSA carry forward all applicable
comments into future ATER Report submittals. Please assure that the applicable
items above are carried forward into all future A TER Reports as well."
There is no map of the settlement stands provided. Please provide an updated
map of the settlement stand system, incorporating all corresponding adjustments
from above.
Comments from previous comment letters, as applicable, will be carried forward into future ATER reports.
A map of the Settlement Monitors as they existed at the time of the 2009 ATER is attached to this letter.
2. Liner Maintenance.
In 2009 a liner damage accident, occurring on May 14,2009, was reported to DRC by a DUSA
notification letter dated May 19, 2009. Necessary repairs to the liner were documented to DRC by
DUSA email dated June 26, 2009.
In the subject September 30, 2009 ATER, under the monthly summary tab, some of the monthly
inspection tables have entries which indicate liner damage, as follows:
A. For April 6-7, 2009, the monthly inspection summary table notes small
puncture(s) in the southwest comer of Cell 4A. The Cell 4A BAT Monitoring,
Operations and Maintenance Plan provides a repair method for damaged liner in
Cell 4A.
B. For April 27-May 1, 2009, the corresponding monthly inspection summary tables
report that the east bank of Cell 1 has liner being repaired. Liner repair on Cell 1
is to be accomplished by use of the current Liner Maintenance Provisions. In an
email received from you on February 25, 2010, you stated this repair site is the
same as that documented in the above paragraph below Liner Maintenance.
Please provide copies of the documentation for the repair and testing for item 2A
above, in accordance with the applicable procedure.
The reference to liner damage in the southwest corner of Cell 4A during the April 6 and 7, 2009
inspection was investigated by the Radiation Safety department and was determined to be a wrinkle in the
HDPE liner, which had the appearance of being a hole or puncture from the observation location on the
top of the dike. No additional action was required.
DENISO
MINES
Letter to Dane L. Finerfrock
April 23, 2010
Page 3
3. Movement Monitoring.
A. In the subject April 23, 2009 DRC letter it states, "we request DUSA provide the
criteria used for evaluation of monitor movement in the text of the ATER report.
Include the corresponding analysis of the most active single grouping of
monuments within the A TER report. Please submit this information for approval."
In-the subject September 30, 2009:ATER, page 9;the first paragraph states that,
"The Majority ofthe Cell 4A points were disturbed during the Cell re-lining
activities and were re-set in the fall of 2008. For these points there is no
meaningful comparison back to previous points."
The remark above appears to refer only to the disturbance movement monitors
located on the dikes of Cell4A. However, there are also movement monitors on
the southern dike of Cell 3. No evaluation was submitted regarding these
movement monitors. Please discuss the use of these monitors for movement
evaluation as mentioned in first paragraph given in 3A above.
The following comments were made with respect to the Movement Monuments on the Cell 3 dike on page 9 of
the 2009 ATER:
"None of the points along the Cell 3 dike or the two (2) Cell 4A dikes show any abnormal
movement. There is no trend in the Cell 3 or Cell 4A movement monitors.
Survey data provided by Jones and Dem ilie Engineers of Richfield, Utah, was reviewed during the
evaluation. The current data was compared to the previous two (2) years data. Evaluation of the data
indicated only very minor movement may have occurred along the Cell 3 dike and the north south Cell 4A
dike. All the possible movements were within expected and acceptable limits."
B. In our subject letter dated April 23, 2009 with respect to the movement monitors
we stated, "Specifically, DRC is asking for the quantitative criteria DUSA uses to
evaluate movement of these monitors, and for such to be printed in the actual text
of the ATER report."
Continuing on this subject in the above letter, it states, "... we are asking for the
upcoming ATER report text to provide this information. DUSA needs to develop
quantitative criteria to evaluate horizontal monitor movement and include this with
evaluation ofthe most active group of monitors in the text ofthe annual A TER
reports. This needs to commence with the 2009 report."
The September 30,2009 ATER makes some reference to quantitative analysis,
but the specific criteria requested is not printed in the text of this report, as
requested. We therefore request that DUSA provide the previously requested
criteria-DUSA uses to evaluate movement of monitors, and for such to be printed
in the actual text ofthe ATER report.
The criteria used for evaluation of monitor movement needs to be put into the
current ATER text. The criteria must stand alone. The criteria may be applied
whenever valid movement monitor data is available.
As a part of the recent proposed modifications to the Radioactive Material License No. UT 1900479 (DRC 04),
DUSA committed to provide DRC with a "Movement (Displacement) Monitoring Standard Operating Procedure"
DENISO
MINES
Letter to Dane L. Finerfrock
April 23, 2010
Page 4
which in part will include the following:
"11.6 Movement (Displacement) Monitorino Standard Operating Procedure - the licensee shall submit for
Executive Secretary approval a written Movement Monitoring Standard Operating Procedure (SOP) on
or before December 1, 2010. The proposed SOP shall describe methods for monitoring potential
vertical and horizontal movements in the constructed dike portions of the tailings management cells,
and for recording and documenting displacement monitoring data and comparing such data to previous
data to track potential movement (displacement). All data collected by the Licensee for these purposes
shall be included in an annual report to be submitted to the Executive Secretary, pursuant to License
Condition 12.3. The SOP shall also:
F. Provide quantitative performance criteria and describe how such criteria will be used to
evaluate movements (displacements);
I. Indicate that results and records of movements (displacements) shall be submitted annually as
part of the ATER required by License Condition 12.3."
DUSA will endeavor to have a draft of this SOP to DRC at the time of the submittal of the 2010 ATER, and
utilize the draft criteria in the evaluation of the newly acquired movement monument data
C. The contains a copy ofa drawing titled UMETCO Minerals Corporation, Survey
Control at White Mesa Mill, Blanding, Utah, dated August 27, 1992. The drawing
has many labeled numeric points which are illegible even with a magnifying glass.
Please supply a clear legible copy of this map.
A revised copy the map indicating the locations of the cell dike movement monuments is attached.
We are hopeful that this information and the enclosed attachments satisfy the DRC Request for Information.
If you have any questions on the attached information and documents please feel free to contact me at (303)
389-4132.
Yours very truly,
DENISON MINES (USA) CORP.
Jo Ann Tischler
Director, Compliance and Permitting
Enclosures
cc: Ron F. Hochstein, w/ attachment
Harold R. Roberts, w/ attachment
Rich E. Bartlett, w/ attachment
David Turk, w/ attachment
DENISO
MINES