DRC-2009-005818 - 0901a06880144aac

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Dave Rupp - Revisions to the Liner Maintenance Procedure-White Mesa Mill
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From: Steve Landau <[e-mail]>
To: "[e-mail]" <[e-mail]>
Date: 10/19/2009 2:43 PM
Subject: Revisions to the Liner Maintenance Procedure-White Mesa Mill
CC: Dave Rupp <[e-mail]>, David Frydenlund <[e-mail]>, Harold
Roberts <[e-mail]>, David Turk <[e-mail]>
Attachments: ScanOOl 2845.PDF; ScanOOl 1876.PDF
Dear Mr. Finerfrock,
Please find attached the revisions to the Liner Maintenance Provisions-Cells 1, 2, 3 and Roberts Pond pertaining to the White
Mesa Mill. Both a redline/strikeout copy and final revision are attached. These revisions incorporate the recommendations of
Mr. Rupp in his correspondence of September 22, 2009. If you should have any questions regarding these changes please
contact me.
Sincerely,
Steven D. Landau
Manager, Environmental Affairs
Steve Landau
Manager. Environmental Affairs
t: [phone] | f: [phone]
1050 17th Street, Suite 950, Denver, CO 80265
DENISON MINES (USA) CORP
www.denisonmines.com
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file://C:\Documents and Settings\Dmpp\Local Settings\Temp\XPgrpwise\4ADC7B0DEQDOMAINEQ... 10/20/2009
Liner Maintenance Provisions-Cells 1, 2, 3 and Roberts Pond Rev. I (|()-IMI9)
Inspections
Tailings cells 1, 2, and 3 are the subject of comprehensive daily inspections which are
conducted by either the Environmental Technician or the Radiation Technician, as well
as once per shift Daily Operations Inspections which are conducted by the Mill Shift
Foreman or other trained personnel designated by the Shift Foreman. The details of these
daily inspections are outlined in Sections 2.1 and 2.2 of the •White Mesa Mill Tailings
Management System and Discharge Mmimization Technology (DMT) Monitoring Plan.
In each case, these inspections are recorded on inspection forms (Daily Inspection Data
Form and Operating Foreman's Daily Inspection Form, respectively). In addition, non-
recorded Daily Operations Patrols are conducted twice per shift by operations personnel.
With regard to Roberts Pond, this facility is observed on a weekly basis when the
Environmental or Radiation Technicieui visits the facility for the recording of water levels
at that location.
Training
All individuals performing inspections described in Sections 2.1 and 2.2 of the DMT
Monitoring Plan must have Tailings Management System Training as described in
Appendix C to the DMT Monitoring Plan (Tailings Inspection Training). As and element
of the "Operational Systems" inspection, inspectors are trained and required to observe
the conditions of the PVC liner. Because the PVC liners in Tailings Cells 1, 2 and 3 are
sensitive to sunlight and can degrade as a result of prolonged exposure, inspectors are
cautioned to observe any situation where the liner is exposed. These exposure situations
are considered serious and requhe immediate attention. Inspectors are trained to cover
small areas of exposure immediately, whereas, larger areas are reported to the radiation
Safety Officer to prompt the issuance of a work order to the Maintenance Department. In
keeping with this inspection requirement, inspectors are trained to observe any
degradation of exposed liners. Such degradation can be that caused by exposure to
sunlight, abrasion due to erosive wave action and/or any rips or tears in the liner material.
Given the fact that the liner material is provided with an earthen cover, erosive damage
and/or rips and tears are unlikely. Inspectors are tramed to record all observations of
liner exposure or disrepair on the inspection report, as well as the date and nature of any
repair activity.
Roberts Pond is lined with Hi Density Polyethylene (HDPE) material which is not
sensitive to stm damage and, as such, is not covered with earthen material, hi this case
the inspector observes the conditions of the liner to the extent that visual observation is
possible (i.e. above the water level and any visually observable near surface condition).
As is the case for the tailing cell inspections, the liner will be observed for any abrasion
due to erosive wave action and/or any rips or tears in the liner material.
Repairs
Repairs to PVC liners in Cells 1, 2 and 3 and to the HDPE liner in Roberts Pond are made
on a case by case basis and usually involves the installation of a repair patch over the
damaged location. PVC patches require the use of glues or adhesive solvents to fuse the
patch to the repair location. HDPE repairs are accomplished by use of an extrusion
welder. Subsequent to any repair of a liner, the repair location will be tested using a
"vacuum box" and soapy water to assure that the repair is acceptable. Te.'U.'t are
conducted such that test ;u-eas ovcrtap bV.ac least K)% of the minimum vacuum chambei
length or at Icsisi 2 inches, whichever!-» gi'efiter until the entire seam has facea test<?d.
The observation of bubbles through the repair seam while vacuum (4-8 psi per ASTM
P5641) is being applied to the seam constitutes seam failure and the repair must be
redone until all seams are acceptable. In the case of Cells 1, 2, and 3, after a patch has
been applied, the repair location must be covered with earthen material, again to avoid
exposure to sunlight. Adequate supplies of PVC and HDPE liner material, repair
material and vacuum test equipment are maintained either in the Mill warehouse or the
maintenance department. The continued availability of these supplies will be verified as
an element of the Quarterly Tailings Inspection conducted by the Radiation Safety
Officer or his designee.
Any leak, hole or other damage to the liners in Cells 1, 2, 3 and the Roberts Pond will be
reported orally to the Executive Secretary within 24 hours of the discovery and in writing
within 5 days of the discovery. The oral and written notifications will include a
notification and description of the failure in accordance with Part I.G.3.(a) of the GWDP
and be in accordance with R317-6-6.16.C(l) of the regulations, hi addition to the
descriptive information about the failure, a plan and schedule for the FML repair will be
included with the notification to the Executive Secretary (in accordance with Part
LG.3.(c) of the Permit).
Repair Report
Each report will be signed by a Utah licensed professional engineer and will address the
following elements as they apply to the case-by-case repairs which are implemented:
• Repair narrative describing the nature of the damage and the repair work
completed to repair the damage.
• Repair material type used to complete the repair
• Repair material description
• Post repairs test specifications
• Test Methods (ASTM D5641-eiretheFl
• Daily reports during the repair work
• Repair test results
• Quality Assiurance/Quality Control Information
Liner Maintenance Provisions-Cells 1, 2, 3 and Roberts Pond Rev. 1 (10-18-09)
Inspections
Tailings cells 1, 2, and 3 are the subject of comprehensive daily inspections which are
conducted by eitlier the Environmental Technician or the Radiation Technician, as well
as once per shift Daily Operations Inspections which are conducted by the Mill Shift
Foreman or otlier trained personnel designated by the Shift Foreman. The details of these
daily inspections are outlined in Sections 2.1 and 2.2 of the "White Mesa Mill Tailings
Management System and Discharge Minimization Technology (DMT) Monitoring Plan,
hi each case, these inspections are recorded on inspection forms (Daily Inspection Data
Form and Operating Foreman's Daily Inspection Form, respectively). In addition, non-
recorded Daily Operations Patrols are conducted twice per shift by operations personnel.
With regard to Roberts Pond, this facility is observed on a weekly basis when the
Environmental or Radiation Technician visits the facility for the recording of water levels
at that location.
Training
All individuals peifonning inspections described in Sections 2.1 and 2.2 of the DMT
Monitoring Plan must have Tailings Management System Training as described in
Appendix C to the DMT Monitoring Plan (Tailings Inspection Training). As and element
of the "Operational Systems" inspection, inspectors are trained and required to obsei-ve
the conditions of the PVC liner. Because the PVC liners in Tailings Cells 1, 2 and 3 are
sensitive to sunlight and can degrade as a result of prolonged exposure, inspectors are
cautioned to observe any situation where the liner is exposed. These exposure situations
are considered serious and require immediate attention. Inspectors are trained to cover
small areas of exposure immediately, whereas, larger areas are reported to the radiation
Safety Officer to prompt the issuance of a work order to the Maintenance Department. In
keeping with this inspection requirement, inspectors are trained to observe any
degradation of exposed liners. Such degiadation can be that caused by exposure to
sunlight, abrasion due to erosive wave action and/or any rips or tears in the liner material.
Given the fact that the liner material is provided with an earthen cover, erosive damage
and/or rips and tears are unlikely, bispectors are trained to record all observations of
liner exposure or disrepair on the inspection report, as well as the date and nature of any
repair activity.
Roberts Pond is lined with Hi Density Polyethylene (HDPE) material which is not
sensitive to sun damage and, as such, is not covered with earthen material. In this case
the inspector observes the conditions of the liner to the extent that visual observation is
possible (i.e. above the water level and any visually observable near surface condition).
As is the case for the tailing cell inspections, the liner will be observed for any abrasion
due to erosive wave action and/or any rips or tears in the liner material.
Repairs
Repairs to PVC liners in Cells 1, 2 and 3 and to tlie HDPE liner in Roberts Pond are made
on a case by case basis and usually involves the installation of a repair patch over the
damaged location. PVC patches require the use of glues or adhesive solvents to fuse the
patch to the repair location. HDPE repairs are accomplished by use of an extrusion
welder. Subsequent to any repair of a liner, the repair location will be tested using a
"vacuum box" and soapy water to assure tliat the repair is acceptable. Tests are
conducted such tliat test areas overlap by at least 10% of the minimum vacuum chamber
length or at least 2 inches, whichever is greater until the entire seam has been tested.
The observation of bubbles through the repair seam while vacuum (4-8 psi per ASTM
D5641) is being applied to the seam constitutes seam failure and the repah must be
redone until all seams are acceptable. In the case of Cells 1, 2, and 3, after a patch has
been applied, the repair location must be covered with earthen material, again to avoid
exposure to sunlight. Adequate supplies of PVC and HDPE liner material, repair
material and vacuum test equipment are maintained either in the Mill warehouse or the
maintenance department. The continued availability of these supplies will be verified as
an element of the Quarterly Tailings Inspection conducted by the Radiation Safety
Officer or his designee.
Any leak, hole or other damage to tlie liners in Cells 1, 2, 3 and the Roberts Pond will be
reported orally to the Executive Secretary within 24 hours of the discovery and in writing
within 5 days of the discovery. The oral and written notifications will include a
notification and description of the failure in accordance with Part I.G.3.(a) of the GVS^P
and be in accordance with R317-6-6.16.C(l) of the regulations. In addition to the
descriptive information about the failure, a plan and schedule for the FML repair will be
included with the notification to the Executive Secretary (in accordance with Pait
LG.3.(c) of the Permit).
Repair Report
Each report will be signed by a Utah licensed professional engineer and will address the
following elements as they apply to the case-by-case repairs which are implemented:
• Repair narrative describing the nature of the damage and the repair work
completed to repair the damage.
• Repair material type used to complete the repair
• Repair material description
• Post repairs test specifications
• Test Methods (ASTM D5641)
• Daily reports during the repair work
• Repair test results
• Quality Assurance/Quality Control Information