DRC-2011-007648 - 0901a06880292877

DENISO
MINES
December 2, 2011
Denison Mines (USA) Corp.
105017th Street, Suite 950
Denver, CO 80265
USA
Tel: [phone]
Fax: [phone]
www.denisonmines.com
VIA E-MAIL AND OVERNIGHT DELIVERY
Mr. Rusty Lundberg
Utah Department of Environmental Quality
195 North 1950 West
P.O. Box 144850
Salt Lake City, UT 84114-4850
Re: White Mesa Mill Revised Contingency Plan as Contemplated by State of Utah Groundwater
Discharge Permit UGW370004
Dear Mr. Lundberg:
Enclosed please find Revision 4 to Denison Mines (USA) Corp.'s ("Denison's") White Mesa Uranium Mill
Contingency Plan. The enclosed revision was developed in response to:
1. redlined edits and comments received from the Utah Division of Radiation Control ("DRG") on
November 8, 2011
2. telephone discussions with DRC on November 22, 2011, and
3. a November 22, 2011 email from Russell Topham of DRC documenting the agreements made between
DRC and Denison during the telephone discussion.
For ease of review we have enclosed both a redlined and a clean copy of the proposed Revision 4. Electronic
files in MS Word format have been submitted separately.
Please contact me if you have any questions or require any further information.
Yours very truly,
DENISON MINES (USA) CORP.
9-
Jo Ann Tischler
Director, Compliance and Permitting
cc: David C. Frydenlund
Harold R. Roberts
David E. Turk
K. Weinel
White Mesa Mill - Standard Date: 9A012/11 Revision:
Operating Procedures DUSA-34
Book #19—Groundwater Page lofl 5
Discharge Permit Plans and
Procedures
WHITE MESA URANIUM MILL
CONTINGENCY PLAN
As Contemplated by Part l.G.4(d)
of
State of Utah Groundwater Discharge Permit No.UGW370004
Prepared by:
Denison Mines (USA) Corp.
1050 17"' Street, Suite 950
Denver CO 80265
September 2December 2, 2010
White Mesa Mill - Standard
Operating Procedures
Book #19- Groundwater
Discharge Permit Plans and
Procedures
Date: 9/40-12/11 Revision:
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Page 2 of 16
TABLE OF CONTENTS
1.0 INTRODUCTION 3
2.0 PURPOSE 3
3.0 GROUNDWATER CONTAMINATION 3
3.1 Notification 4
4
4
5
4.0 MILL DISCHARGE VIOLATIONS - INCLUDING UNAUTHORIZED
DISCHARGE OR RELEASE OF PROHIBITED CONTAMINANTS TO THE
TAILING CELLS 6
4.1 Notifications 6
4.2 Field Activities 6
7
5.0 DMT VIOLATIONS 7
5.1 Tailings Cell Wastewater Pool Elevation Above the Maximum Elevations ... ...7
5.2 Excess Head in Tailines Cells 2. 3. 4A. and 4B Slimes Drain Svstefns 8
5.3 Excess Cell 4A Leak Detection Svstem Fluid Head or Daily Leak Rate
5.4 Excess Cell 4B Leak Detection System Fluid Head or Dailv Leak Rate 10
5.5 Excess New Decontamination Pad Leak Detection Svstem Fluid Head 11
5.6 Cracks or Physical Discrepancies on New Decontamination Pad Wash Pad.. . 11
1?
13
13
14
15
5.12 Failure to Complv with Stormwater Management and Spill Control
Requirements 15
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Discharge Pemiit Plans and
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WHITE MESA URANIUM MILL
CONTINGENCY PLAN
State of Utah Groundwater Discharge Permit
No. UGW370004
1.0 INTRODUCTION
Formatted: Heading 1, No bullets or
numbering
The State of Utah has granted Ground Water Discharge Permit No. UGW370004 (the
"GWDP") for Denison Mines (USA) Corp.'s ("Denison's") White Mesa Uranium Mill
(the "Mill"). The GWDP specifies the construction, operation, and monitoring
requirements for all facilities at the Mill that have a potential to discharge pollutants
directly or indirectly into groundwaterthe underlying aquifer.
2. 2.0 PURPOSE
Formatted: Heading 1, No bullets or
numbering
This Contingency Plan (the "Plan") provides a detailed list of actions Denison will take to
regain compliance with GWDP limits and Discharge Minimization Technology Plan
("DMT") and the Best Available Technology Plan ("BAT") requirements defined in Parts
I.C, I.D, and I.H.4 of the GWDP. The timely execution of contingency and corrective
actions outlined in this Plan will provide Denison with the basis to exercise the
Affirmative Action Defense provision in Part I.G.3.c) of the GWDP and thereby avoid
noncompliance status and potential enforcement action'.
The contingency actions required to regain compliance with GWDP limits and DMT and
BAT requirements defined in Parts I.C, I.D, and I.H.4 of the GWDP are described below.
3,0 GROUNDWATER CONTAMINATION
Formatted: Heading 1, No bullets or
numbering
Since there are many different possible scenarios that could potentially give rise to
groundwater contamination, and since the development and implementation of a
remediation program will normally be specific to each particular scenario, this Plan does
not outline a definitive remediation program. Rather, this Plan describes the steps that
' Part I.G.3.C) of the GWDP provides that, in the event a compliance action is initiated against Denison for
violation of permit conditions relating to best available technology or DMT, Denison may affirmatively
defend against that action by demonstrating that it has made appropriate notifications, that the failure was
not intentional or caused by Denison's negligence, that Denison has taken adequate measures to meet
permit conditions in a timely manner or has submitted an adequate plan and schedule for meeting permit
conditions, and that the provisions of UCA 19-5-107 have not been violated.
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will be followed by Denison in the event Denison is found to be out of compliance with
respect to any constituent in any monitoring well, pursuant to Part I.G.2 of the GWDP.
When the concentration of any parameter in a compliance monitoring well is out of
compliance, Denison will, subject to specific requirements of the Executive Secretary as
set forth in any notice, order, remediation plan or the equivalent, implement the following
process:
3^3.1 Notification
Denison will notify the Executive Secretary of the out of compliance status within 24
hours after detection of that status followed by a written notice within 5 days after
detection, as required under Part I.G.4.a) of the GWDP.
3.2 Continuation of Accelerated Monitoring
Denison will continue accelerated sampling for the parameter in that compliance
monitoring well pursuant to Part I.G.I of the GWDP, unless the Executive Secretary
determines that other periodic sampling is appropriate, until the facility is brought into
compliance, as required under Part I.G.4.b) of the GWDP.
If the accelerated monitoring demonstrates that the Mill-monitoring well has retumed to
is no longer out of compliance with respect to a parameter in a well, then, with the
written approval ef-from the Executive Secretary, Denison will cease accelerated
monitoring for thate parameter, and no further steps will be followed by Denison with
respect to such parameter.will continue routine monitoring for that parameter.
^T+T 3.3 Submission of Plan and Timetable
Formatted: Heading 2, No bullets or
numbering
If the accelerated monitoring confirms that the Mill is out of compliance with respect to a
parameter in a well, then, within 30 days of such confirmation, Denison will prepare and
submit to the Executive Secretary a plan and a time schedule for assessment of the
sources, extent and potential dispersion of the contamination, and an evaluation of
potential remedial action to restore and maintain ground water quality to ensure that
permit limits will not be exceeded at the compliance monitoring point and that DMT or
BAT will be reestablished, as required under part I.G.4.c) of the GWDP. This plan will
normally include, but is not limited to:
a) The requirement for Denison to prepare a detailed and comprehensive
operational history of the facility and surrounding areas which explores all
activities that may have contributed to the contamination;
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b) A requirement for Denison to complete an evaluation, which may include
geochemical and hydrogeological analyses, to determine whether or not the
contamination was caused by Mill activities or was caused by natural forces or
offsite activities;
c) If it is concluded that the contamination is the result of current or past activities
at the Mill, Denison will prepare a Characterization Report, which characterizes
the physical, chemical, and radiological extent of the ground water
contamination. This will normally include a description of any additional wells
to be used or installed to characterize the plume and the hydrogeologic
characteristics of the affected zone, the analytical parameters to be obtained, the;
samples of ground water to be taken, and any other means to measure and
characterize the affected ground water and contamination zone; and
d) If it is concluded that the contamination is the result of current or past activities
at the Mill, Denison will evaluate potential remedial actions, including actions
to restore and maintain groundwater quality to ensure that permit limits will not
be exceeded at the compliance monitoring point and that DMT and BAT will be
reestablished, as well as actions that merely allow natural attenuation to operate
and actions that involve applying for Altemate Concentration Limits ("ACLs").
ACLs require approval of the Water Qualitv Board prior to becoming effective.
If groundwater remediation is required, Denison will prepare and submit te
thefor Executive Secretary approval a Ground Water Remediation Plan, as
described in Section 3.4 below.
5T2T 3.4 Groundwater Remediation Plan
Formatted: Heading 2, No bullets or
numbering
If the Executive Secretary determines that ground water remediation is needed, Denison
will submit a Ground Water Remediation Plan to the Executive Secretary within the time
frame requested by the Executive Secretary. The Ground Water Remediation Plan will
normally include, but is not limited to:
a) A description and schedule of how Denison will implement a corrective action -
program that prevents contaminants from exceeding the ground water protection
levels or ACLs at the compliance monitoring point(s) or other locations
approved by the Executive Secretary, by removing the contaminants, treating
them in place, or by other means as approved by the Executive Secretary;
b) A description of the remediation monitoring program to demonstrate the
effectiveness of the plan; and
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c) Descriptions of how corrective action will apply to each source of the pollution.
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Denison will implement the Ground Water Remediation Plan in accordance with a
schedule to be submitted by Denison and approved by the Executive Secretary.
4. 4,0 MILL DISCHARGE VIOLATIONS-INCLUDING
UNAUTHORIZED DISCHARGE OR RELEASE OF PROHIBITED
CONTAMINANTS TO THE TAILING CELLS
Part I.C.2. ofthe GWDP provides that only 1 le.(2) by-product material authorized by the
Mill's State of Utah Radioactive Materials License No. UT-2300478 (the "Radioactive
Materials License") shall be discharged to or disposed of in the Mill's taihngs cells.
Part I.C.3 ofthe GWDP provides that discharge of other compounds into the Mill's
tailings cells, such as paints, used oil, antifreeze, pesticides, or any other contaminant not
defined as 1 le.(2) material is prohibited.
In the event of any unauthorized disposal of contaminants or wastes (the "Unauthorized
Materials") to the Mill's tailings cells, Denison will, subject to any specific requirements
ofthe Executive Secretary as set forth in any notice, order, remediation plan or the
equivalent, implement the following process:
Formatted: Heading 1, No bullets or
numbering
I Formatted: Keep with next
AAr 4.1 Notifications
Formatted: Heading 2, No bullets or
numbering
a) Upon discovery, the Mill Manager or RSO will be notified immediately; and
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification within five days of
discovery.
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after: 0.61" + Indent at: 0.61"
4^ 4.2 Field Activities
Formatted: Heading 2, No bullets or
numbering
a) Upon discovery, Mill persoimel will immediately cease placement of "
Unauthorized Materials into the Mill's tailings cells;
b) To the extent reasonably practicable and in a manner that can be accomplished
safely. Mill personnel will attempt to segregate the Unauthorized Materials from
other tailings materials and mark or record the location of the Unauthorized
Materials in the tailings cells. If it is not reasonably practicable to safely
segregate the Unauthorized Material from other tailings materials. Mill
personnel will nevertheless mark or record the location of the Unauthorized
Materials in the tailings cells;
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Alignment: Left + Aligned at: 0.31" + Tab
after: 0.61" + Indent at: 0.61"
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Operating Procedures
Book #19- Groundwater
Discharge Permit Plans and
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Date: 9/40-12/11 Revision:
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c) To the extent reasonably practicable and in a manner that can be accomplished
safely. Mill personnel will attempt to remove the Unauthorized Material from
the tailings cells; and
d) Denison will dispose of the removed Unauthorized Material under applicable
State and Federal regulations with the approval of the Executive Secretary.
4.3 .Request for Approvals and/or Waivers
Formatted: Heading 2, No bullets or
numbering
If it is not reasonably practicable to safely remove the Unauthorized Materials from the
tailings cells, then Denison will, in accordance with a schedule to be approved by the
Executive Secretary:
a) Submit a written report to the Executive Secretary analyzing the health, safety
and environmental impacts, if any, associated with the permanent disposal of the
Unauthorized Material in the Mill's tailings cells;
b) Apply to the Executive Secretary for any amendments that may be required to
the GWDP and the Radioactive Materials License to properly accommodate the
permanent disposal of the Unauthorized Material in the Mill's tailings cells in a
manner that is protective of health, safety and the environment; and
c) Make all applications required under the United States Nuclear Regulatory
Commission's ("NRC's") Non-1 le.(2) Disposal Policy (NRC Regulatory Issue
Summary 2000-23 (November 200O),Jnterim Guidance on Disposal o fNon-
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-j Formatted: Font: Italic
Atomic Energy Act of1954, Section lle.(2) Byproduct Material in Tailings
Impoundments), including obtaining approval of the Department of Energy as
the long term custodian of the Mill's tailings, in order to obtain approval to
permanently dispose of the Unauthorized Material in the Mill's tailings cells.
5.0 DMT VIOLATIONS
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numbering
&^ 5.1 _Tailings Cell Wastewater Pool Elevation Above the Maximum Elevations
Formatted: Heading 2, No bullets or
numbering
Part I.D.2 and Part I.D.6.d) of the GWDP provide that authorized operation and
maximum disposal capacity in each of the existing tailings cells shall not exceed the
levels authorized by the Radioactive Materials License and that under no circumstances
shall the freeboard be less than three feet, as measured from the top of the flexible
membrane liner ("FML").
White Mesa Mill - Standard
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Book #19- Groundwater
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In the event that tailings cell wastewater pool elevation in any tailings cell exceeds the
maximum elevations mandated by Part 1.D.2 and Part I.D.6.d) of the GWDP, Denison
will, subject to any specific requirements of the Executive Secretary as set forth in any
notice, order, remediation plan or the equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification within five days of
discovery;
c) Upon discovery. Mill personnel will cease to discharge any further tailings to
the subject tailings cell, until such time as adequate freeboard capacity exists in
the subject tailings cell for the disposal of the tailings;
d) To the extent reasonably practicable, without causing a violation of the
freeboard limit in any other tailings cell. Mill personnel will promptly pump
fiuids from the subject tailings cell to another tailings cell until such time as the
freeboard limit for the subject tailings cell is in compliance. If there is no room
available in another tailings cell, without violating the freeboard limit of such
other cell, then, as soon as reasonably practicable. Mill personnel will cease to
discharge any further tailings to any tailings cell until such time as adequate
freeboard capacity exists in all tailings cells;
e) If it is not reasonably practicable to pump sufficient solutions from the subject
tailings cell to another tailings cell, then the solution levels in the subject
tailings cell will be reduced through natural evaporation; and
f) Denison will perform a root cause analysis of the exceedance and will
implement new procedures or change existing procedures to minimize the
chance of a recurrence.
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Numbering Style: a, b, c,... + Start at: 1 +
Alignment: Left + Aligndl at: 0.31" + Tab
after: 0.61" + Indent at: 0.61"
^5.2 Excess Head in Tailings Cells 2, 3^ 4A, and 4BA Slimes Drain Systems
Part I.D.3.b)l) of the GWDP provides that Denison shall at all times maintain the average
wastewater head in the slimes drain access pipe in Cell 2 to be as low as reasonably
achievable, in accordance with the Mill's currently approved DMT Monitoring Plan , and
that for Cell 3, this requirement shall apply only after initiation of de-watering operations.
Similarly, Part I.D.6.c) of the GWDP provides that after Denison initiates pumping
conditions in the slimes drain layer in Cell 4A, Denison will provide: 1) continuous
declining fluid heads in the slimes drain layer, in a manner equivalent to the requirements
'{ Formatted: No underiine
Formatted: Heading 2, No bullets or
numbering
White Mesa Mill - Standard
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Book #19- Groundwater
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found in Part I.D.3.b); and 2) a maximum head of I.O feet in the tailings (as measured
from the lowest point of the upper FML) in 6.4 years or less.
In the event that the average wastewater head in the slimes drain access pipe for Cell 2 or,
after initiation of de-watering activities. Cell 3 or initiation of pumping conditions in the
slimes drain layer in Cell 4A exceeds the levels specified in the DMT Monitoring Plan,
Denison will, subject to any specific requirements of the Executive Secretary as set forth
in any notice, order, remediation plan or the equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately; "
b) Mill personnel will promptly pump the excess fluid into an active tailings cell,
or other appropriate containment or evaporation facility approved by the
Executive Secretary;
c) If the exceedance is the result of equipment failure. Mill personnel will attempt
to repair or replace the equipment;
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Alignment: Left + Aligned at: 0.31" + Tab
after: 0.61" + Indent at: 0.61"
d) If the cause of the exceedance is not rectified within 24 hours, Denison will
provide verbal notification to the Executive Secretary within the ensuing 24
hours followed by a written notification within five days; and
e) If not due to an identified equipment failure, Denison will perform a root cause
analysis of the exceedance and will implement new procedures or change
existing procedures to minimize the chance of a recurrence.
^T^T 5.3 Excess Cell 4A Leak Detection System Fluid Head or Daily Leak Rate
Formatted: Heading 2, No bullets or
numbering
Part I.D.6.a) provides that the fluid head in the Leak Detection System ("LDS") for Cell
4A shall not exceed 1 foot above the lowest point in the lower membrane liner, and Part
l.D.6.b) ofthe GWDP provides that the maximum allowable daily leak rate measured in
the LDS for Cell 4A shall not exceed 24,160 gallons/day.
hi the event that the fluid head in the LDS for Cell 4A exceeds 1 foot above the lowest
point in the lower membrane layer or the daily leak rate measured in the Cell 4A LDS
exceeds 24,160 gallons/day, Denison will, subject to any specific requirements of the
Executive Secretary as set forth in any notice, order, remediation plan or the equivalent,
implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Mill personnel will promptly pump the excess fiuid into an active tailings cell,
cell, or other appropriate containment or evaporation facility approved by the
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Numbering Style: a, b, c,.;. + Start at: 1 +
Alignment: Left + Aligned at: 0.31" + Tab
after: 0.61" + Indent at: 0.61"
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Operating Procedures
Book #19- Groundwater
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Date: 9/40-12/11 Revision:
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Executive Secretary, until such time as the cause of exceedance is rectified or
until such time as otherwise directed by the Executive Secretary;
c) If the exceedance is the result of equipment failure. Mill personnel will attempt
to repair or replace the equipment;
d) If the cause of the exceedance is not rectified within 24 hours, Denison will
provide verbal notification to the Executive Secretary within the ensuing 24
hours followed by a written notification within five days; and
e) If not due to an identified equipment failure, Denison will perform a root cause
analysis of the exceedance and will implement new procedures or change
existing procedures to remediate the exceedance and to minimize the chance of
a recurrence.
5.4 Excess Cell 4B Leak Detection System Fluid Head or Daily Leak Rate
Formatted: Heading 2, No bullets or
numbering
Part I.D. 13.a) provides that the fluid head in the Leak Detection System ("LPS") for Cell
4B shall not exceed 1 foot above the lowest point in the lower membrane liner, and Part
I.D.13.b') of the GWDP provides that the maximum allowable daily leak rate measured in
the LDS for Cell 4B shall not exceed 26.145 gallons/day.
In the event that the fluid head in the LDS for Cell 4B exceeds 1 foot above the lowest
point in the lower membrane layer or the daily leak rate measured in the Cell 4B LDS
exceeds 26,145 gallons/day, Denison will, subiect to any specific requirements ofthe
Executive Secretary as set forth in any notice, order, remediation plan or the equivalent,
implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately:
b) Mill personnel will promptly pump the excess fluid into an active tailings cell,
or other appropriate containment or evaporation facility approved by the
Executive Secretary, until such time as the cause of exceedance is rectified or
until such time as otherwise directed by the Executive Secretary;
c) If the exceedance is the result of equipment failure. Mill personnel will attempt
to repair or replace the equipment;
If the cause of the exceedance is not rectified within 24 hours, Dertison will
provide verbal notification to the Executive Secretary within the ensuing 24
hours followed by a written notification within five davs; and
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If not due to an identified equipment failure, Denison will perform a root cause analysis
of the exceedance and will implement new procedures or change existing procedures to
remediate the exceedance and to minimize the chance of a recurrence.
5.5 Excess New Decontamination Pad Leak Detection System Fluid Head
Formatted: Heading 2, No bullets or
numbering
In order to ensure that the primary containment of the New Decontamination Pad water
collection system has not been compromised, and to provide an inspection capability to
detect leakage from the primary containment in each of the three settling tanks, a vertical
inspection portal has been installed between the primary and secondary containment of
each settling tank.
Section 3.1(e) of the Mill's DMT Monitoring Plan provides that the fluid head in the LDS
for the New Decontamination Pad shall not exceed 0.10 feet above the concrete floor in
any of the three standpipes. Compliance is defined in Part I.D. 14 a) of the GWDP as a
depth to standing water present in any of the LDS access pipes of more than or equal to
6.2 feet as measured from the water measuring point (top of access pipe).
In the event that the fluid head in the standpipe for a settling tank exceeds 0.10 feet above
the concrete floor in the standpipe, Denison will, subject to any specific requirements of
the Executive Secretary as set forth in any notice, order, remediation plan or the
equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Denison will provide verbal notification to the Executive Secretary within the
ensuing 24 hours followed by a written notification within five days;
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after: 0.61" + Indent at: 0.61"
c) Mill personnel will promptly pump the fluid from the settling tank's LDS as
well as the fluids in the settling tank into another settling tank or into an active
tailings cell, or other appropriate containment or evaporation facility approved
by the Executive Secretary, until such time as the cause of the exceedance is
rectified or until such time as otherwise directed by the Executive Secretary; and
d) Denison will perform a root cause analysis of the exceedance and, if
appropriate, will implement new procedures or change existing procedures to
remediate the exceedance and to minimize the chance of a recurrence.
Pad.
5.6 Cracks or Physical Discrepancies on the-New Decontamination Pad Wash
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Soil and debris will be removed form the wash pad of the NDP in accordance with the
currently approved DMT Monitoring Plan. In the event that cracks of greater than 1/8
inch (width) ei^^tber physical discrepmeies-are observed on the concrete wash pad,
Denison will, subject to any specific requirements of the Executive Secretary as set forth
in any notice, order, remediation plan or the equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) The NEDP shall be taken out of service and the cracks or deficiencies will be
repaired utilizing industry standard materials and procedures appropriate for the
defect within five working days of discovery. Following recommended cure
times, the cracks or deficiencies will be re-inspected and, if acceptable, the
NEDP will be placed back into service.
c) A record of the repairs will be maintained as a part of the inspection records at
the White Mesa Mill.
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after: 0.61" + Indent at: 0.61"
&S: 5.7 Excess Elevation For Tailings Solids
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numbering
Part 1.D.3.C) of the GWDP provides that upon closure of any tailings cell, Denison shall
ensure that the maximum elevation of the tailings waste solids does not exceed the top of
the FML.
In the event that, upon closure of any tailings cell, the maximum elevation of the tailings
waste solids exceeds the top of the FML, Denison will, subject to any specific
requirements of the Executive Secretary as set forth in any notice, order, remediation plan
or the equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification within five days of
discovery;
c) To the extent reasonably practicable, without causing a violation of the
freeboard limit in any other tailings cell. Mill personnel will promptly remove
tailings solids fi-om the subject tailings cell to another tailings cell, or other
location approved by the Executive Secretary, until such time as the maximum
elevation of the tailings waste solids in the subject tailings cell does not exceed
the top of the FML; and
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Numbering Style: a, b, c,... + Start at: 1 +
Alignment: Left + Aligned at: 0.31" + Tab
after: 0.61" + Indent at: 0.61"
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d) Denison will perform a root cause analysis of the exceedance and will
implement new procedures or change existing procedures to minimize the
chance of a recurrence.
5.8 Roberts Pond Wastewater Elevation
Formatted: Heading 2, No bullets or
numbering
Part I.D.3.e) of the GWDP provides that the Permittee shall operate Roberts Pond so as to
provide a minimum 2-foot freeboard at all times and that under no circumstances shall
the water level in Roberts Pond exceed an elevation of 5,624 feet above mean sea level.
In the event that the wastewater elevation exceeds this maximum level, Denison shall
remove the excess wastewater and place it into containment in Tailings Cell 1 within 72
hours of discovery, as specified in Part I.D.3.e) of the GWDP.
In the event that, Denison fails to-se remove any suchthe excess wastewater within 72
hours of discovery. Denison will, subject to any specific requirements of the Executive
Secretary as set forth in any notice, order, remediation plan or the equivalent, implement
the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately; and
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification and proposed corrective
actions within five days of discovery.
5v87 5.9 Feedstock Storage Area
Formatted: Outline numbered + Level: 4 +
Numbering Style: a, b, c,... + Start at: 1 +
Alignment: Left + Aligned at: 0.31" + Tab
after: 0.61" + Indent at: 0.61"
Formatted: Heading 2, No bullets or
numbering
Part l.D.3.f) and Part I.D.I I of the GWDP provide that open-air or bulk storage of all
feedstock materials at the Mill facility awaiting Mill processing shall be limited to the
eastem portion of the Mill site area described in Table 4 of the GWDP, and that storage
of feedstock materials at the facility outside that area shall be performed in accordance
with the provisions of Part I.D.I 1 ofthe GWDP.
In the event that, storage of any feedstock at the Mill is not in compliance with the
requirements specified in Part I.D.3.f) and Part I.D.I 1 of the GWDP, Denison will,
subject to any specific requirements of the Executive Secretary as set forth in any notice,
order, remediation plan or the equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately; Formatted: Outline numbered + Level: 4 +
Numbering Style: a, b, c,... + Start at: 1 +
Alignment: Left + Aligned at: 0.31" + Tab
after: 0.61" + Indent at: 0.61"
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Page 14 of 16
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification within five days of
discovery;
c) Mill personnel will:
(i) move any open-air or bulk stored feedstock materials to the portion ofthe
Mill site area described in Table 4 of the GWDP;
(ii) ensure that any feedstock materials that are stored outside ofthe area
described in Table 4 of the GWDP are stored and maintained in
accordance with the provisions of Part I.D.I 1 of the GWDP; and
(iii) to the extent that any such containers are observed to be leaking, such
leaking containers will be placed into watertight over-pack containers or
otherwise dealt with in accordance with the provisions of Part I.D.I 1 of
the GWDP, and any impacted soils will be removed and will be deposited
into the Mill's active tailings cell; and
d) Denison will perform a root cause analysis of the non-compliant activity and
will implement new procedures or change existing procedures to minimize the
chance of a recurrence.
5.10 Mill Site Chemical Reagent Storage
Formatted: Heading 2, No bullets or
numbering
Part l.D.3.g) of the GWDP provides that for all chemical reagents stored at existing
storage facilities, Denison shall provide secondary containment to capture and contain all
volumes of reagent(s) that might be released at any individual storage area, and that for
any new construction of reagent storage facilities, the secondary containment and control
shall prevent any contact of the spilled reagent with the ground surface.
In the event that Denison does notfails to provide the required secondary containment
required under Part l.D.3.g) of the GWDP, Denison will, subject to any specific
requirements of the Executive Secretary as set forth in any notice, order, remediation plan
or the equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification within five days of
discovery; and
c) Denison will promptly remediate any spilled re-agent resulting from the failure
failure to provide the required secondary containment under Part I.D.3.g) ofthe
Formatted: Outline numbered + Level: 4 +
Numbering Style: a, b, c,... + Start at: 1 +
Alignment: Left + Aligned at: 0.31" + Tab
after: 0.61" + Indent at: 0.61"
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GWDP, by removal of the contaminated soil and disposal in the active tailings
cell.
5.10. 5.11 Failure to Construct as per Approval
Formatted: Heading 2, No bullets or
numbering
Part 1.D.4 ofthe GWDP provides that any construction, modification, or operation of new
waste or wastewater disposal, treatment, or storage facilities shall require submittal of
engineering design plans and specifications, and prior Executive Secretary review and
approval, and that a Construction Permit may be issued.
In the event that, any new waste or wastewater disposal, treatment, or storage facilities
are constructed at the Mill facility without obtaining prior Executive Secretary review
and approval, or any such facilities are not constructed in accordance with the provisions
ofany applicable Construction Permit, Denison will, subject to any specific requirements
ofthe Executive Secretary as set forth in any notice, order, remediation plan or the
equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately; and
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification and proposed corrective
actions within five days of discovery.
Formatted: Outline.numbered + Level: 4 +
Numbering Style: a, b, c,... + Start at: 1 +
Alignment: Left + Aligned at: 0.31" + Tab
after: 0.61" + Indent at: 0.61"
5.11. 5.12 Failure to Comply with Stormwater Management and Spill Control
Requirements
Part I.D. 10 ofthe GWDP provides that Denison will manage all contact and non-contact
stormwater and control contaminant spills at the Mill facility in accordance with the
currently approved Stormwater Best Management Practices Plan.
In the event that any contact or non-contact stormwater or contaminant spills are not
managed in accordance with the Mill's approved Stormwater Best Management Practices
Plan, Denison will, subject to any specific requirements of the Executive Secretary as set
forth in any notice, order, remediation plan or the equivalent, implement the following
process:
Formatted: Heading 2, No bullets or
numbering
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification and proposed corrective
actions within five days of discovery; and
Formatted: Outline numbered + Level: 4 +
Numbering Style: a, b, c,... + Start at: 1 +
Alignment: Left + Aligned at: 0.31" + Tab
after: 0^61" + Indent at: 0,61"
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Discharge Permit Plans and
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c) To the extent still practicable at the time of discovery, Denison will manage any
such contaminant spill in accordance with the Mill's approved Stormwater Best
Management Practices Plan. To the extent it is no longer practicable to so
manage any such spill, Denison will agree with the Executive Secretary on
appropriate clean up and other measures.
Formatted: Outline numbered + Level: 4 +
Numbering Style: a, b, c,... + Start at: 1 +
Alignment: Left + Aligned at: 0.31" + Tab
after: 0.61" .+Indent at: 0.61"
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Discharge Permit Plans and
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WHITE MESA URANIUM MILL
CONTINGENCY PLAN
As Contemplated by Part LG.4(d)
of
State of Utah Groundwater Discharge Permit No.UGW370004
Prepared by:
Denison Mines (USA) Corp.
1050 17"" Street, Suite 950
Denver CO 80265
December 2, 2010
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Discharge Pennit Plans and
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TABLE OF CONTENTS
1.0 INTRODUCTION 3
2.0 PURPOSE 3
3.0 GROUNDWATER CONTAMINATION 3
3.1 Notification 4
3.2 Continuation of Accelerated Monitoring 4
3.3 Submission of Plan and Timetable 4
3.4 Groundwater Remediation Plan 5
4.0 MILL DISCHARGE VIOLATIONS - INCLUDING UNAUTHORIZED
DISCHARGE OR RELEASE OF PROHIBITED CONTAMINANTS TO THE
TAILING CELLS 6
4.1 Notifications 6
4.2 Field Activities 6
4.3 Request for Approvals and/or Waivers 7
5.0 DMT VIOLATIONS 7
5.1 Tailings Cell Wastewater Pool Elevation Above the Maximum Elevations 7
5.2 Excess Head in Tailings Cells 2, 3, 4A, and 4B Slimes Drain Systems 8
5.3 Excess Cell 4A Leak Detection System Fluid Head or Daily Leak Rate 9
5.4 Excess Cell 4B Leak Detection System Fluid Head or Daily Leak Rate 10
5.5 Excess New Decontamination Pad Leak Detection System Fluid Head 11
5.6 Cracks or Physical Discrepancies on New Decontamination Pad Wash Pad.... 11
5.7 Excess Elevation For Tailings Solids 12
5.8 Roberts Pond Wastewater Elevation 13
5.9 Feedstock Storage Area 13
5.10 Mill Site Chemical Reagent Storage 14
5.11 Failure to Construct as per Approval 15
5.12 Failure to Comply with Stormwater Management and Spill Control
Requirements 15
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Discharge Pennit Plans and
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WHITE MESA URANIUM MILL
CONTINGENCY PLAN
State of Utah Groundwater Discharge Permit
No. UGW370004
1.0 INTRODUCTION
The State of Utah has granted Ground Water Discharge Permit No. UGW370004 (the
"GWDP") for Denison Mines (USA) Corp.'s ("Denison's") White Mesa Uranium Mill
(the "Mill"). The GWDP specifies the construction, operation, and monitoring
requirements for all facilities at the Mill that have a potential to discharge pollutants
directly or indirectly into the underlying aquifer.
2.0 PURPOSE
This Contingency Plan (the "Plan") provides a detailed list of actions Denison will take to
regain compliance with GWDP limits and Discharge Minimization Technology Plan
("DMT") and the Best Available Technology Plan ("BAT") requirements defined in Parts
I.C, I.D, and LH.4 of the GWDP. The timely execution of contingency and corrective
actions outlined in this Plan will provide Denison with the basis to exercise the
Affirmative Action Defense provision in Part I.G.3.c) of the GWDP and thereby avoid
noncompliance status and potential enforcement action^
The contingency actions required to regain compliance with GWDP limits and DMT and
BAT requirements defined in Parts I.C, I.D, and I.H.4 of the GWDP are described below.
3.0 GROUNDWATER CONTAMINATION
Since there are many different possible scenarios that could potentially give rise to
groundwater contamination, and since the development and implementation of a
remediation program will normally be specific to each particular scenario, this Plan does
not outline a definitive remediation program. Rather, this Plan describes the steps that
' Part I.G.3.C) ofthe GWDP provides that, in the event a compliance action is initiated against Denison for
violation of pennit conditions relating to best available technology or DMT, Denison may affirmatively
defend against that action by demonstrating that it has made appropriate notifications, that the failure was
not intentional or caused by Denison's negligence, that Denison has taken adequate measures to meet
pemiit conditions in a timely manner or has submitted an adequate plan and schedule for meeting permit
conditions, and that the provisions of UCA 19-5-107 have not been violated.
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Discharge Permit Plans and
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will be followed by Denison in the event Denison is found to be out of compliance with
respect to any constituent in any monitoring well, pursuant to Part I.G.2 of the GWDP.
When the concentration of any parameter in a compliance monitoring well is out of
compliance, Denison will, subject to specific requirements of the Executive Secretary as
set forth in any notice, order, remediation plan or the equivalent, implement the following
process:
3.1 Notification
Denison will notify the Executive Secretary of the out of compliance status within 24
hours afl:er detection of that status followed by a written notice within 5 days after
detecfion, as required under Part I.G.4.a) of the GWDP.
3.2 Continuation of Accelerated Monitoring
Denison will continue accelerated sampling for the parameter in that compliance
monitoring well pursuant to Part I.G. 1 of the GWDP, unless the Executive Secretary
determines that other periodic sampling is appropriate, until the facility is brought into
compliance, as required under Part I.G.4.b) of the GWDP.
If the accelerated monitoring demonstrates that the monitoring well has retumed to
compliance with respect to a parameter in a well, then, with written approval from the
Executive Secretary, Denison will cease accelerated monitoring for that parameter, and
will continue routine monitoring for that parameter.
3.3 Submission of Plan and Timetable
If the accelerated monitoring confirms that the Mill is out of compliance with respect to a
parameter in a well, then, within 30 days of such confirmation, Denison will prepare and
submit to the Executive Secretary a plan and a time schedule for assessment of the
sources, extent and potential dispersion of the contamination, and an evaluation of
potential remedial action to restore and maintain ground water quality to ensure that
permit limits will not be exceeded at the compliance monitoring point and that DMT or
BAT will be reestablished, as required under part I.G.4.c) of the GWDP. This plan will
normally include, but is not limited to:
a) The requirement for Denison to prepare a detailed and comprehensive
operational history of the facility and surrounding areas which explores all
activities that may have contributed to the contamination;
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Discharge Pennit Plans and
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b) A requirement for Denison to complete an evaluation, which may include
geochemical and hydrogeological analyses, to determine whether or not the
contamination was caused by Mill activities or was caused by natural forces or
offsite activities;
c) If it is concluded that the contamination is the result of current or past activities
at the Mill, Denison will prepare a Characterization Report, which characterizes
the physical, chemical, and radiological extent of the ground water
contamination. This will normally include a description of any additional wells
to be used or installed to characterize the plume and the hydrogeologic
characteristics of the affected zone, the analytical parameters to be obtained, the
samples of ground water to be taken, and any other means to measure and
characterize the affected ground water and contamination zone; and
d) If it is concluded that the contamination is the result of current or past activities
at the Mill, Denison will evaluate potential remedial actions, including actions
to restore and maintain groundwater quality to ensure that permit limits will not
be exceeded at the compliance monitoring point and that DMT and BAT will be
reestablished, as well as actions that merely allow natural attenuation to operate
and actions that involve applying for Altemate Concentration Limits ("ACLs").
ACLs require approval of the Water Quality Board prior to becoming effective.
If groundwater remediation is required, Denison will prepare and submit for
Executive Secretary approval a Ground Water Remediation Plan, as described in
Section 3.4 below.
3.4 Groundwater Remediation Plan
If the Executive Secretary determines that ground water remediation is needed, Denison
will submit a Ground Water Remediation Plan to the Executive Secretary within the time
fi-ame requested by the Executive Secretary. The Ground Water Remediation Plan will
normally include, but is not limited to:
a) A description and schedule of how Denison will implement a corrective action
program that prevents contaminants fi'om exceeding the ground water protection
levels or ACLs at the compliance monitoring point(s) or other locations
approved by the Executive Secretary, by removing the contaminants, treating
them in place, or by other means as approved by the Executive Secretary;
b) A description of the remediation monitoring program to demonstrate the
effectiveness of the plan; and
c) Descriptions of how corrective action will apply to each source of the pollution.
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Page 6 of 15
Denison will implement the Ground Water Remediation Plan in accordance with a
schedule to be submitted by Denison and approved by the Executive Secretary.
4.0 MILL DISCHARGE VIOLATIONS - INCLUDING UNAUTHORIZED
DISCHARGE OR RELEASE OF PROHIBITED CONTAMINANTS TO THE
TAILING CELLS
Part I.C.2. of the GWDP provides that only 1 le.(2) by-product material authorized by the
Mill's State of Utah Radioacfive Materials License No. UT-2300478 (the "Radioactive
Materials License") shall be discharged to or disposed of in the Mill's tailings cells.
Part I.C.3 of the GWDP provides that discharge of other compounds into the Mill's
tailings cells, such as paints, used oil, antifi-eeze, pesticides, or any other contaminant not
defined as 11 e.(2) material is prohibited.
In the event of any unauthorized disposal of contaminants or wastes (the "Unauthorized
Materials") to the Mill's tailings cells, Denison will, subject to any specific requirements
of the Executive Secretary as set forth in any notice, order, remediation plan or the
equivalent, implement the following process:
4.1 Notifications
a) Upon discovery, the Mill Manager or RSO will be notified immediately; and
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification within five days of
discovery.
4.2 Field Activities
a) Upon discovery. Mill personnel will immediately cease placement of
Unauthorized Materials into the Mill's tailings cells;
b) To the extent reasonably practicable and in a manner that can be accomplished
safely. Mill personnel will attempt to segregate the Unauthorized Materials from
other tailings materials and mark or record the location of the Unauthorized
Materials in the tailings cells. If it is not reasonably practicable to safely
segregate the Unauthorized Material firom other tailings materials, Mill
personnel will nevertheless mark or record the location of the Unauthorized
Materials in the tailings cells;
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c) To the extent reasonably practicable and in a manner that can be accomplished
safely. Mill personnel will attempt to remove the Unauthorized Material from
the tailings cells; and
d) Denison will dispose of the removed Unauthorized Material under applicable
State and Federal regulations with the approval of the Executive Secretary.
4.3 Request for Approvals and/or Waivers
If it is not reasonably practicable to safely remove the Unauthorized Materials from the
tailings cells, then Denison will, in accordance with a schedule to be approved by the
Executive Secretary:
a) Submit a written report to the Executive Secretary analyzing the health, safety
and environmental impacts, if any, associated with the permanent disposal ofthe
Unauthorized Material in the Mill's tailings cells;
b) Apply to the Executive Secretary for any amendments that may be required to
the GWDP and the Radioactive Materials License to properly accommodate the
permanent disposal of the Unauthorized Material in the Mill's tailings cells in a
manner that is protective of health, safety and the environment; and
c) Make all applications required under the United States Nuclear Regulatory
Commission's ("NRC's") Non-1 le.(2) Disposal Policy (NRC Regulatory Issue
Summary 2000-23 (November 2000), Interim Guidance on Disposal of Non-
Atomic Energy Act of1954, Section lie. (2) Byproduct Material in Tailings
Impoundments), including obtaining approval of the Department of Energy as
the long term custodian of the Mill's tailings, in order to obtain approval to
permanently dispose of the Unauthorized Material in the Mill's tailings cells.
5.0 DMT VIOLATIONS
5.1 Tailings Cell Wastewater Pool Elevation Above the Maximum Elevations
Part I.D.2 and Part I.D.6.d) of the GWDP provide that authorized operation and
maximum disposal capacity in each of the existing tailings cells shall not exceed the
levels authorized by the Radioactive Materials License and that under no circumstances
shall the freeboard be less than three feet, as measured from the top ofthe flexible
membrane liner ("FML").
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In the event that tailings cell wastewater pool elevation in any tailings cell exceeds the
maximum elevations mandated by Part I.D.2 and Part I.D.6.d) of the GWDP, Denison
will, subject to any specific requirements of the Executive Secretary as set forth in any
notice, order, remediation plan or the equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be nofified immediately;
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification within five days of
discovery;
c) Upon discovery. Mill personnel will cease to discharge any ftirther tailings to
the subject tailings cell, until such time as adequate freeboard capacity exists in
the subject tailings cell for the disposal of the tailings;
d) To the extent reasonably practicable, without causing a violation of the
freeboard limit in any other tailings cell. Mill personnel will promptly pump
fluids from the subject tailings cell to another tailings cell until such time as the
freeboard limit for the subject tailings cell is in compliance. If there is no room
available in another tailings cell, without violating the freeboard limit of such
other cell, then, as soon as reasonably practicable. Mill personnel will cease to
discharge any further tailings to any tailings cell until such time as adequate
freeboard capacity exists in all tailings cells;
e) If it is not reasonably practicable to pump sufficient solutions from the subject
tailings cell to another tailings cell, then the solution levels in the subject
tailings cell will be reduced through natural evaporation; and
f) Denison will perform a root cause analysis of the exceedance and will
implement new procedures or change existing procedures to minimize the
chance of a recurrence.
5.2 Excess Head in Tailings Cells 2, 3, 4A, and 4B Slimes Drain Svstems
Part I.D.3.b)l) of the GWDP provides that Denison shall at all times maintain the average
wastewater head in the slimes drain access pipe in Cell 2 to be as low as reasonably
achievable, in accordance with the Mill's currently approved DMT Monitoring Plan , and
that for Cell 3, this requirement shall apply only after initiation of de-watering operations.
Similarly, Part I.D.6.c) of the GWDP provides that after Denison initiates pumping
conditions in the slimes drain layer in Cell 4A, Denison will provide: 1) continuous
declining fluid heads in the slimes drain layer, in a manner equivalent to the requirements
found in Part I.D.3.b); and 2) a maximum head of 1.0 feet in the tailings (as measured
from the lowest point of the upper FML) in 6.4 years or less.
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In the event that the average wastewater head in the slimes drain access pipe for Cell 2 or,
after initiation of de-watering activities, Cell 3 or initiation of pumping conditions in the
slimes drain layer in Cell 4A exceeds the levels specified in the DMT Monitoring Plan,
Denison will, subject to any specific requirements of the Executive Secretary as set forth
in any notice, order, remediation plan or the equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Mill personnel will promptly pump the excess fluid into an active tailings cell,
or other appropriate containment or evaporation facility approved by the
Executive Secretary;
c) If the exceedance is the result of equipment failure. Mill personnel will attempt
to repair or replace the equipment;
d) If the cause of the exceedance is not rectified within 24 hours, Denison will
provide verbal notification to the Executive Secretary within the ensuing 24
hours followed by a written notification within five days; and
e) If not due to an identified equipment failure, Denison will perform a root cause
analysis of the exceedance and will implement new procedures or change
existing procedures to minimize the chance of a recurrence.
5.3 Excess Cell 4A Leak Detection System Fluid Head or Daily Leak Rate
Part I.D.6.a) provides that the fluid head in the Leak Detection System ("LDS") for Cell
4A shall not exceed 1 foot above the lowest point in the lower membrane liner, and Part
I.D.6.b) of the GWDP provides that the maximum allowable daily leak rate measured in
the LDS for Cell 4A shall not exceed 24,160 gallons/day.
In the event that the fluid head in the LDS for Cell 4A exceeds 1 foot above the lowest
point in the lower membrane layer or the daily leak rate measured in the Cell 4A LDS
exceeds 24,160 gallons/day, Denison will, subject to any specific requirements of the
Executive Secretary as set forth in any notice, order, remediation plan or the equivalent,
implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Mill personnel will promptly pump the excess fluid into an active tailings cell,
or other appropriate containment or evaporation facility approved by the
Executive Secretary, until such time as the cause of exceedance is rectified or
until such time as otherwise directed by the Executive Secretary;
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c) If the exceedance is the result of equipment failure. Mill personnel will attempt
to repair or replace the equipment;
d) If the cause of the exceedance is not rectified within 24 hours, Denison will
provide verbal notification to the Executive Secretary within the ensuing 24
hours followed by a written notification within five days; and
e) If not due to an identified equipment failure, Denison will perform a root cause
analysis of the exceedance and will implement new procedures or change
existing procedures to remediate the exceedance and to minimize the chance of
a recurrence.
5.4 Excess Cell 4B Leak Detection System Fluid Head or Daily Leak Rate
Part I.D. 13.a) provides that the fluid head in the Leak Detection System ("LDS") for Cell
4B shall not exceed 1 foot above the lowest point in the lower membrane liner, and Part
I.D.13.b) of the GWDP provides that the maximum allowable daily leak rate measured in
the LDS for Cell 4B shall not exceed 26,145 gallons/day.
In the event that the fluid head in the LDS for Cell 4B exceeds 1 foot above the lowest
point in the lower membrane layer or the daily leak rate measured in the Cell 4B LDS
exceeds 26,145 gallons/day, Denison will, subject to any specific requirements of the
Executive Secretary as set forth in any notice, order, remediation plan or the equivalent,
implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Mill personnel will promptly pump the excess fluid into an active tailings cell,
or other appropriate containment or evaporation facility approved by the
Executive Secretary, until such time as the cause of exceedance is rectified or
until such time as otherwise directed by the Executive Secretary;
c) If the exceedance is the result of equipment failure. Mill personnel will attempt
to repair or replace the equipment;
d) If the cause of the exceedance is not rectified within 24 hours, Denison will
provide verbal notification to the Executive Secretary within the ensuing 24
hours followed by a written notification within five days; and
If not due to an identified equipment failure, Denison will perform a root cause analysis
ofthe exceedance and will implement new procedures or change existing procedures to
remediate the exceedance and to minimize the chance of a recurrence.
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5.5 Excess New Decontamination Pad Leak Detection System Fluid Head
In order to ensure that the primary containment of the New Decontamination Pad water
collection system has not been compromised, and to provide an inspection capability to
detect leakage from the primary containment in each of the three settling tanks, a vertical
inspection portal has been installed between the primary and secondary containment of
each settling tank.
Section 3.1(e) of the Mill's DMT Monitoring Plan provides that the fluid head in the LDS
for the New Decontamination Pad shall not exceed 0.10 feet above the concrete floor in
any of the three standpipes. Compliance is defined in Part I.D. 14 a) of the GWDP as a
depth to standing water present in any of the LDS access pipes of more than or equal to
6.2 feet as measured from the water measuring point (top of access pipe).
In the event that the fluid head in the standpipe for a settling tank exceeds 0.10 feet above
the concrete floor in the standpipe, Denison will, subject to any specific requirements of
the Executive Secretary as set forth in any notice, order, remediation plan or the
equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Denison will provide verbal notification to the Executive Secretary within the
ensuing 24 hours followed by a written notification within five days;
c) Mill personnel will promptly pump the fluid from the settiing tank's LDS as
well as the fluids in the settling tank into another settling tank or into an active
tailings cell, or other appropriate containment or evaporation facility approved
by the Executive Secretary, until such time as the cause of the exceedance is
rectified or until such time as otherwise directed by the Executive Secretary; and
d) Denison will perform a root cause analysis of the exceedance and, if
appropriate, will implement new procedures or change existing procedures to
remediate the exceedance and to minimize the chance of a recurrence.
5.6 Cracks or Physical Discrepancies on New Decontamination Pad Wash Pad.
Soil and debris will be removed form the wash pad of the NDP in accordance with the
currentlv approved DMT Monitoring Plan. In the event that cracks of greater than 1/8
inch (width) are observed on the concrete wash pad, Denison will, subject to any specific
requirements of the Executive Secretary as set forth in any notice, order, remediation plan
or the equivalent, implement the following process:
White Mesa Mill - Standard
Operating Procedures
Book # 19 - Groundwater
Discharge Permit Plans and
Procedures
Date: 12/11 Revision: DUSA-4
Page 12 of 15
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) The NDP shall be taken out of service and the cracks will be repaired utilizing
industry standard materials and procedures appropriate for the defect within five
working days of discovery. Following recommended cure times, the cracks or
deficiencies will be re-inspected and, if acceptable, the NDP will be placed back
into service.
c) A record of the repairs will be maintained as a part of the inspection records at
the White Mesa Mill.
5.7 Excess Elevation For Tailings Solids
Part I.D.3.C) of the GWDP provides that upon closure of any tailings cell, Denison shall
ensure that the maximum elevation of the tailings waste solids does not exceed the top of
the FML.
In the event that, upon closure of any tailings cell, the maximum elevation of the tailings
waste solids exceeds the top of the FML, Denison will, subject to any specific
requirements of the Executive Secretary as set forth in any notice, order, remediation plan
or the equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification within five days of
discovery;
c) To the extent reasonably practicable, without causing a violation of the
freeboard limit in any other tailings cell, Mill personnel will promptly remove
tailings solids from the subject tailings cell to another tailings cell, or other
location approved by the Executive Secretary, until such time as the maximum
elevation ofthe tailings waste solids in the subject tailings cell does not exceed
the top of the FML; and
d) Denison will perform a root cause analysis of the exceedance and will
implement new procedures or change existing procedures to minimize the
chance of a recurrence.
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Operating Procedures
Book #19- Groundwater Page 13 of 15
Discharge Permit Plans and
Procedures
5.8 Roberts Pond Wastewater Elevation
Part I.D.3.e) of the GWDP provides that the Permittee shall operate Roberts Pond so as to
provide a minimum 2-foot freeboard at all times and that under no circumstances shall
the water level in Roberts Pond exceed an elevation of 5,624 feet above mean sea level.
In the event that the wastewater elevation exceeds this maximum level, Denison shall
remove the excess wastewater and place it into containment in Tailings Cell 1 within 72
hours of discovery, as specified in Part I.D.3.e) of the GWDP.
In the event that, Denison fails to remove the excess wastewater within 72 hours of
discovery, Denison will, subject to any specific requirements of the Executive Secretary
as set forth in any notice, order, remediation plan or the equivalent, implement the
following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately; and
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification and proposed corrective
actions within five days of discovery.
5.9 Feedstock Storage Area
Part I.D.3.f) and Part I.D.I 1 of the GWDP provide that open-air or bulk storage of all
feedstock materials at the Mill facility awaiting Mill processing shall be limited to the
eastem portion of the Mill site area described in Table 4 of the GWDP, and that storage
of feedstock materials at the facility outside that area shall be performed in accordance
with the provisions of Part I.D.I 1 ofthe GWDP.
In the event that, storage of any feedstock at the Mill is not in compliance with the
requirements specified in Part I.D.3.f) and Part I.D.l 1 of the GWDP, Denison will,
subject to any specific requirements of the Executive Secretary as set forth in any notice,
order, remediation plan or the equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification within five days of
discovery;
c) Mill personnel will:
White Mesa Mill - Standard
Operating Procedures
Book # 19 - Groundwater
Discharge Permit Plans and
Procedures
Date: 12/11 Revision: DUSA-4
Page 14 of 15
(i) move any open-air or bulk stored feedstock materials to the portion ofthe
Mill site area described in Table 4 of the GWDP;
(ii) ensure that any feedstock materials that are stored outside ofthe area
described in Table 4 of the GWDP are stored and maintained in
accordance with the provisions of Part I.D.l 1 of the GWDP; and
(iii) to the extent that any such containers are observed to be leaking, such
leaking containers will be placed into watertight over-pack containers or
otherwise dealt with in accordance with the provisions of Part I.D.l 1 of
the GWDP, and any impacted soils will be removed and will be deposited
into the Mill's active tailings cell; and
d) Denison will perform a root cause analysis of the non-compliant activity and
will implement new procedures or change existing procedures to minimize the
chance of a recurrence.
5.10 Mill Site Chemical Reagent Storage
Part I.D.3.g) of the GWDP provides that for all chemical reagents stored at existing
storage facilities, Denison shall provide secondary containment to capture and contain all
volumes of reagent(s) that might be released at any individual storage area, and that for
any new constmction of reagent storage facilities, the secondary containment and control
shall prevent any contact of the spilled reagent with the ground surface.
In the event that Denison fails to provide the required secondary containment required
under Part I.D.3.g) of the GWDP, Denison will, subject to any specific requirements of
the Executive Secretary as set forth in any notice, order, remediation plan or the
equivalent, implement the following process:
a) Upon discovery, the Mill Manager or RSO will be notified immediately;
b) Denison will provide verbal notification to the Executive Secretary within 24
hours of discovery followed by a written notification within five days of
discovery; and
c) Denison will promptly remediate any spilled re-agent resulting from the failure
to provide the required secondary containment under Part LD.3.g) ofthe
GWDP, by removal of the contaminated soil and disposal in the active tailings
cell.