DRC-2010-003903 - 0901a068801a4703

DRC-2010-003903
DENISO
MINES
June 29, 2010
Oenison Mines (USA) Corp.
105017th Street, Suite 950
Denver, CO 80265
USA
Tel: [phone]
Fax: [phone]
vvww.denisonmlnes.com
VIA PDF AND EXPRESS DELIVERY
Mr. Dane L. Finerfrock
Executive Secretary
Utah Department of Environmental Quality
Division of Radiation Control
195 North 1950 West
P.O. Box 144810
Salt Lake City, UT 84114-4810
Re: Submittal of Revison 3.2 of White Mesa Mill Reclamation Plan, Pursuant to Utah
Radioactive Materials License No. UT 1900479, DRC-04
This letter transmits two copies of Denison Mines (USA) Corp.'s ("Denison's"), Addendum to
update the White Mesa Mill's (the "Mill's") Reclamation Plan and Specifications to address
tailings Cells 4A and 4B as required by Condition 9.11 of the approved Utah Radioactive
Materials License No. UT1900479 DRC-04.
Reclamation Plan Revision 3.2 consists of:
• the contents of approved Revision 3.0 and submittals referred to as Revision 3.1, plus
• the addition ofthe Addendum material transmitted under this letter.
As discussed during our phone call on June 23, 2010, and as required by License Condition 9.11,
the Addendum has been developed from the approved Revision 3.0. To create revision 3.2, we
have prepared, and included in the Addendum, replacements for:
• Section I-Introduction
• Section 2.0, Existing Facility
• Section 3.0, Reclamation Plan
• Figure 1.5-2, A-5.1-1, and A-5.1-2
• Attachment C, Revised Cost Estimate for Reclamation of the White Mesa Mill and
Tailings Management System
As we also discussed during our phone call, for ease of review, the three text secti ons included in
the Addendum have been provided in both redline/strikeout and blackline ("clean") form .
The pages and figures in the Addendum refl ect the types of changes required to update the
approved Reclamation Plan to address both Ce1l4A and Cell 48, and to correct the approved
version to reflect the Mi ll's current environmental monitoring program. These additional
changes have been made to ensure that upon approval, revision 3.2 of the reclamation Plan will
be consistent with the monitoring requirements and commitments in the approved Radioactive
Materials License and the approved Groundwater Discharge Permit.
Denison has noted that Condition 9.1 1 of the Radioactive Materials License requires that
Denison " ... provide information demonstrating the adequacy of the long-term care fund with
respect to the White Mesa Mill Facil ity that includes considerati on of Cells 4A and 48 ... ". The
long term care fund is a fixed value established by 10 CFR Part 40, Appendix A Criterion 10
(incorporated into UAC R313-24-4) to address United States Department of Energy long-term
monitoring and oversight, and is not specific to site co nditions. While this line item is included
in the reclamation surety estimate, the va lue is a fixed value and no change was required to the
estimate to address Cell 4A and 48.
Please contact the me if you have any questions or require any further information.
Yours truly, 9:J2v..A--~_tA '--
Jo Ann Tischler
Director, Compli ance and Permitting
cc: David C, Frydenlund
Ron F. Hochstein
Ryan Palmer
Harold R. Roberis
David E. Turk
OENISOJ)JJ
MINES
2
OENISONI)~~
MINES
Denison Min .. (USA) Corp.
1050 171h Stree~ Suite 950
Denver, CO 80265
USA
rei : 303 628·7798
Fax: [phone]
www.dlnisonmines.com
White Mesa Mill Reclamation Plan
Revision 3.2
Section I
White Mesa Mill and Tailings
Management System
June 2010
State of Utahlle.(2) Byproduct Material License # UT1900479
Denison Mines (USA) Corp.
www.denlsonmlnls.com
1050 17th Street, Suite 950
Oenvor, CO, USA 80265
r ei : 303 628·7798
Fax: [phone]
Page 1-1
Revision 3.2
Denison Mines (USA) Corp.
Wllite Mesa Mill Reclamation Plan
INTRODUCTION
This reclamation Plan (the "plan") has been prepared by Denison Mines (USA) Corp. ("Denison"),
for Denison's Wl1ite Mesa Uranium Mill (the "Mill"), located approximately 6.0 miles south of
Blanding, Utah. The Plan presents Denison's plans and estimated costs for the reclamation of the
Mill's tailings Cells 1,2,3, 4A and 4B, and for decommissioning of the Mill and Mill site.
Summary of Plan
The uranium and vanadium processing areas of the mill, including all equipment, structures and
support facilities will be decommissioned and disposed of in tailings or buried on site as
appropriate. All equipment, including tankage and piping; agitation; process control
instrumentation and switchgears; and contaminated structures; will be cut up, removed, and buried
in tailings prior to final cover placement. Concrete structures and foundations will be demolished
and removed or covered with soil as appropriate.
The sequence of demolition would proceed so as to allow the maximum use of support areas of the
facility, such as the office and shop areas. Any uncontaminated or decontaminated equipment to
be considered for salvage will be released in accordance with the United States Nuclear
Regulatory Commission ("NRC") document, guidance and in compliance with the conditions of
the Mill's State of Utah Radioactive Materials License No. UTI 900479 (the "License"). As with
the equipment for disposal, any contaminated soils from the Mill and surrounding areas and any
ore or feed material on the Mill site will be disposed of in the tailings facilities in accordance with
Section 4.0 of Attachment A, Plans and Specifications.
":\USl~S\WMRCrlN\I"IRO,RP1\I"tl' 2010
Page J-2
Revision 3.2
Denison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
The estimated reclamation costs for surety are set out in Attachment C. Attachment C will be
reviewed and updated on a yearly basis.
Plan Organization
General site characteristics pertinent to this Plan are contained in Section 1.0. Descriptions of
the facility constlUction, operations and monitoring are given in Section 2.0. The cUITent
environmental monitoring program is described in Section 2.3. Seismic risk was assessed in
Section 1.6.3.
The Plan itself, including descriptions of facilities to be reclaimed and design criteria, is presented
in Section 3.0. Section 3.0 Attachments A through H are the Plans and Specifications, Quality
Plan for Construction Activities, Cost Estimates, and supplemental testing and design details.
Supporting documents, which have been reproduced as appendices for ease of review, include:
Semi-Annual EfJ/uent Reports (January through June, 2008), (June through
December, 2008) and (January through June 2009) for the MiJl, which have been
submitted previously on November 24, 2009;
• Site hydrogeology and Estimation of Groundwater Travel Times in the Perched
Zone White Mesa Uranium Mill Site Near Blanding, Utah, August 27, 2009,
prepared by Hydro Geo Chem, Inc. (the "2009 HGC Report), submitted previously
on November 24, 2009;
• The MiJl's Storm water Best Management Practices Plan, Revision 1.3: June 12,
2008, submitted previously on November 24,2009;
• Tailings Cover Design, White Mesa Mill, October 1996. submitted previously on
November 24, 2009;
'f:\lISfR$\\\'MRCI'l"\INl RO.RrllJuM 1010
Page 1-3
Revision 3.2
Denison Mines (USA) Coq).
White Mesa Mill Reclamation Plan
• /Val/ollcli Etl1lSS/01IS Sltlilc/alYlY .!Or /:/azan70tlS Ali' Po/hllailis /(adoll .fan:
Yeast/remeltl Prog/'CIltl, f/7/zite Afesa Ani/ Jlle, 20{M: Tellco Environmental,
submitted previously on November 24,2009; and
• Semi-Annual Monitoring Report July 1 -December 31, 2008 and Annual
Monitoring Summary jor 2008, White Mesa Mill Meteorological Station, January
20, 2009 McVehil-Monnett Associates, Inc., submitted previously on November
24,2009.
As required by Part LELII of the Mill's State of Utah Ground Water Discharge Permit No.
UGW370004 (the "GWDP"), Denison is in the process of completing an infiltration and
contamination transport model of the final tailings cover system to demonstrate the
long-term ability of the cover to protect nearby groundwater quality. Upon review of such
modeling, the executive Secretary of the State of Utah radiation Control Board (the
"Executive Secretary") will detennine if changes to the cover system as set out in the Plan
are needed to ensure compliance with the perfonnance criteria contained in Pmi LD.8 of
the GWDP. Although the modeling has not been completed, modeling results to date
suggest that some changes to the final cover design as set out in the Plan will be needed.
However, as the details of such re-design have not been finalized at this time, the approved
2000 cover design and basis will continue to be used for this version of the Plan. This
Plan will be amended in the future to incorporate any changes to the design of the tailings
cover system that result from the CUl1'ent modeling effort.
Page 1--1
Revision 2-:O.ll
IntemotieRol UroniumDenison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
I NTRoo"CTION
This deeufftent reclamation Plan (the "plan") has been prepared by IRtemati6nai Uf8niumDenison
Mines (USA) Corp~6fftIien ("!2!enisont/&A"), for Denison's White Mesa Uranium Mill (the
"Mill"), located approx.imately 6.0 miles south of Blanding, Utah. The Plan presents J.IJ.S.A..!s
Denison's plans and estimated costs for the reclamation of the Mill's tailings Cells 1-1,2,3, 4A
and 4..!}, and for decommissioning of the White Mesa Mill and Mill site.
The uranium and vanadium processing areas of the mill, including all equipment, structures and
suppOl1 facil ities will be decommissioned and dis posed of in tailings or buried on site as
appropriate. All equipment, including tan kage and piping; agitation; process control
instrumentati on and switchgears; and contaminated structures; will be cut up, removed, and buried
in tailings prior to final cover placement. Concrete structures and foundations wi ll be demolished
and removed or covered with soil as appropriate. These deeemmissieneEi areas lIeuld inelude,
Bot flet Be limited te, the felle .. iAg:
Cearse ere Bin anEi asseeiateEi eEluiJ'ment, een le)'ers aRd struetures.
Gfine eireuit inelt:leiflg semi Bt:ltegenet:ls grifld (SAG) tHi ll, sereens, J'umJ's afld e)eleRes.
Thfee pre leaeh tanles 1e the east ef the mill Building, ineluding all 8sseeiatee taruEBge,
ogitatien eEluipment, pumps, 8nd piping.
Se.en le8eH tenlEs inside the maifl mill i:luileing, ineludiflg all 8sseeiatea 8gitetien
equipment, f'UIHf'S 8nd f'iping.
Ceunter eUffent deeefl:tatien (CGO} eireuit ineluaing ell thieleeners ene eElt:lif'JHent, f'UJHf's
aful f'iping.
Urenium f'reeiJ'it8tien eireuit, ineluding ell thieleeners, f'ump5 enEi f'if'ing.
T'" e ) elle.o e8he dryers 8nEl all meeH8flieei ane eleetrie81 stlf'f'ert eEluipment, ineluding
Uf8fl:iUIH }3eeh:aging equipment.
Clafifiers te the '",est efthe miJ.J...&t:tHding-ineltt&ing tke f'rele8eH thielEefler anEi elorleefl:&..
.. \U .... \ ... , __ ,.o .. ~
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Tab stops: Not at ·1"
Page 1--2
Revision W3.2
IfltematieRsi Uf8RiumDenison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
Beiler anti 811 BReilla" eEtUirHHent BRd buildiftgs.
E:fuire '1BRotiium I3feeif.litetieR, aryiflg, BREI rusis" eireuit.
All eltteR!oel t8Rleege Ret iRehuletl ift the ehs\'e list in eluding: reegeR! 18ftles fer tke sterage
efeeiti, emmsfli8,IEer8seRe, water, BF 8F)' ehemieals; BRd tke \8f1S8iHm 8Jtitlatiefl eireuit.
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.... ____ Y!f!ofti~~ _8!l~ _ ._8fll!d_i~f!l_ s_e!\:.e!,~ !!'!*!:8_e!i~,! J~ryl ~tr~l:I_i~ !"_e!u..difl$_ ~I! _8](_ ~f}t! .!'~B~~'!t ___ --{ Formatted: Font: (Default) TImes New Roman )
tBRiEsge, IfliJters BRa settlers, pumps, 8f1Eil3ipiRg.
8X •• ildiftg.
Mill •• ildiftg.
Ofliee •• ildiftg.
SABP 8f1:d 'N8Fehsl;;Ise Intil8ing;
--.£8,.mple-j>kml-BHihli..g,
The sequence of demolition would proceed so as to allow the maximum use of support areas of the
facility, such as the office and shop areas. It is 8Atieipatedlh8t 811 majef struetHres aAe lar-ge
eElHipmeAt .. ill he eemalishee with the use ef hydfaHlie sheafs. These'll ill speed the j9faeess,
"ra, ide j9ral,ef siziHg afthe matefials Ie he "laeed iA teiliRg:9, eHe fedHee eJt!3aSHfe ta radi8tiaA eHd
athef ssfet)' hS:tSfeS eHfing the demalitien. Any uncontaminated or decontaminated equipment to
be considered for sa lvage will be released in accordance with the United States Nuclear
Regulatory Commission ("N RC:) document, "G..uJ~~Ln~!!. fe! _~e_e~~t~~in_s!i~~ ~f !,~t;.iD~~s _ f!.A~ _~ ~ ~ i Formatted: No underline
l!Ej:liij9meHI Prier Ie Release fef Unfestficted Use af TermiRSliaft ef LieeRses far B),j9redttet ar
Sauree Materiels, dated Sej9temher, 1984, afta ift eamplieHee .,'ith the eaRditia"s sf Seuree
Material Lieense SUA 1358gu~d.!lnce_and In comilliance w~th the _condi~ions of Jhe_ Mill's S~ate <"!.f_~ ~ -i Formatted: No underline
Utah Radioactive Materials License.No. UT1900479 (the "License''t_ ~~ _~i~h_t~~ ~quil!l1]~nJ [0.]' __ ~ -i Formatted: No underline
disposal, any contaminated soils from the Mmilt and surrounding areas and any ore or feed
material on the Mill site will be disposed of in the tailings facilities in accordance with Section 4,0
of Attachment A, Plans and Specifications,
Page 1--3
Rev ision ~3.2
hltematieflsl Uf8fliufflDenison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
The estimated reclamation costs for surety are sUffl:fAflfi'teties felle ... 's:set out in Attachment C.
Attachment C will be reviewed and updated on a yearly basis.
Direet CD!!.!!
MHl-DeeemmissiooHtg
CellI Reel. lila tieR
Cell) ReelamatioB 1,082,869
Cell 3 ReelamatioH 1,565,444
Cell 4A Reelamati&A
Mise. Item, ('r&jed Ceneral) 1,939,480
Stthtetal Direet. 57,146,257
Prefit AlI8 .. 8nee
Centingene, 1,071,939
bicensing and 8entling
beRg Term CaFe Ftilld
Tetal SU:f'et\ Requirement: S9681167
Page 1---4
Revision 2-:03.2
!ft~Denison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
It_EP9.fl_T 0B9!.!~I~~'J!QtJ~La!.1 Qrg,!niza!ion ________________________________ :~"": r:Fo;;;'.;;m;.;.;;;tted:;;;;;'.;U.;;ode;;;;;;".;;;ne'-______ ~
Formatted: Keep with ne)(t
General site characteristics pertinent to the rcelofflstienthis fplan are contained in Section 1.0.
Descriptions of th e facility construction. operations and monitoring are given in Section 2.0. The
current environmental monitoring program is described in Section 2.3. Seismic risk was assessed
in Section ~1.6.3.
The Reelafflatisfl Plan itself. including descriptions of facil ities to be reclaimed and design criteria,
is presented in Section 3.0. Section 3.0 Attachments A through H are the Plans and
Specifications, Quality Plan for Construction Activities, Cost Estimates, and supplemental testing
and design details.
Suppol1ing documents ..... (pre.isH91) sHemttteer,-which have been reproduced as appendices for
ease of review, include:
~e.!'!i:1.'I!'~I'.!I_ EJ/!!!eJ!! ft!eo../~Ji. !.f'M'~ ~f:esf! ~JUI. ~Ul~' 1358,J~s_e!(~t}I~. 4(:) 8_68! '
(January through June 2008) (June through December. 2008) and f)ul)' th,eugfl
- ---_c Formatted: Font: Italic, No underline
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Deeemeer 1995Januan: thr..9~&h. Jlo!n_e 200.?! _B!1~ #'2'{ A.I'l,!a} _Ef:I!t!eJI{ _R_et!~:1, _____ ~ : -Formatted: Not Highlight
While j~les(f Alit}, SUA 1358. Dsehet Ne. 4(:) 8681, (1BflHBf) thrsHgh JHne 1996) '~~ : }:':',o",m"."tted",,:,' ,:,N:',ot,:H.c~":h,,I~,,:ht;;.., _____ ~
'\ Formatted: Not Highlight
BFler-g), iZtlels Jl-hteleBr. IAe.for the Mill which have been submitted previously on
November 24. 2009;
,
~ ___ :!I~~r~g~sl~~~ ~':. B_II:!BJi_s!,l ~[Y~hit!! Me9~ y~AjU~ Mi!l!.. 1_"1>:0 199_4~ _ ,!,i!B_A _____ :zl----En, irSnfftentBI CSfI'sr8tieA (Tjt8R)~~te _ hydros~ology_ an~ _ Esti'!l~~on ~f _______ _
Groundwater Travel Times in the Perched Zone White Mesa Uranium Mill Site
Near Blanding Utah August 27 2009 prepared by Hydro G~oJ;:~e,,! _Inc. (!h_e ____ u __ -
112009 HGC Report>. submitted previouslx. ~n No~emb_e! ?4.}90~i... ______________ ~: ~
Formatted: Foot: Italic, No underline
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1 + Aligned at: 0.25" + Indent at: as
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Formatted: Font (Default) Times New Roman
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Page \---5
Revision 2-:03.2
ffiteFH8tieRsi Uf8fliumDenison Mines (USA) Corp.
Wh ite Mesa Mi ll Reclamation Plan
.!...-..-____ ~~i~t~ _ ~f_ .?~~~!i~~e!t. _\¥~i!e __ ~e..s~ _ t}!.8.!1~ti_R! }J~~ _ ~ep!e!'!.e_e~ _1.09~1· _____ ::"': Formatted: font: (Default) limes New Roman
+iteftThe Milrs~/,:?m!\!::a!e,. Best ¥!.".!l!_~em_e~t Pr_act;~es Pla!~ .!t~~i!,i.9!:l I}: Jun_e _____ _ Formatted: List Paragraph, Bulleted + level:
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12. 2008. submitted previously on November 24 2009'-: ________________________ _ Formatted: Font: Italic
Formatted: Font: (Default) Times New Roman
~------------------------------------------------------------------Formatted: Foot: Italic
20 2009 McVehil-Monnett Associates. Inc .. submitted previously on November
24.2009.
UGW370004 (the "GWDP·'l. Denison is in the process of comoleting an infiltration and
contamination transport model of the final tailings cover system to demonstrate the
long-term ability of the cover to protect nearby groundwater quality. Upon review of such
modeling. the executive Secretary of the State of Utah radiation Control Board (the
'"Executive Secretary") will determine if changes to the cover system as set out in the Plan
are needed to ensure compliance with the performance criteria contained in Part 1.0.8 of
the GWDP. Although the modeling has not been completed. modeling results to date
suggest that some changes to the final cover design as set out in the Plan will be needed.
However as the details of such re-design have not been finalized at this time. the approved
1 .. \I,I!I ....... , .. O(>lN'..,·O •• ~
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Page I---<i
Revision 2-:-G3.2
ffltemel1eflal UF8ftil::tmDenison Mines (USA) Corp.
Wh ite Mesa Mill Recla mation Plan
2000 cover design and basis will continue to be used for this version of the Plan. This
Plan will be amended in the future to incomorate any changes to the design of the tailings
cover system that result from the current modeling effort..:: __________________________ ~ ~; -{ Formatted: Font: (Default) TImes New Roman I
OENISONr;)~~
MINES
Denison Mines (USA) Corp.
1050 171h Stree~ Suite 950
Denver, CO 80265
USA
rei : 303 628·7798
Fax: [phone]
www.dllnisonmlne •. com
White Mesa Mill Reclamation Plan
Revision 3.2
Section 2
White Mesa Mill and Tailings
Management System
June 2010
State of Utahlle.(2) Byproduct Material License # UT1900479
Denison Mines (USA) Corp.
www.denlsonmln ••. com
1050 17th Streot. Suito 950
Denver. CO, USA 80265
rei: 303 628·7798
Fax : [phone]
Page 2-1
Revision 3.2
Denison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
2.0 EXISTING FACILITY
The following sections describe the construction history of the Mill; the Mill and Mill tailings
management facilities; Mill operations including the Mill circuit and tailings management; and
both operational and environmental monitoring.
2.1 Facility Construction History
The Mill is a uranium/vanadium mill that was developed in the late 1970's by Energy Fuels
Nuclear, Inc. (EFN) as an outlet for the many small mines that are located in the Colorado Plateau
and for the possibility of milling Arizona Strip ores. At the time of its construction, it was
anticipated that high uranium prices would stimulate ore production. However, prices started to
decline about the same time as Mill operations commenced.
As uranium prices fen, producers in the region were affected and mine output declined. After
about two and one-half years, the Mill ceased ore processing operations altogether, began solution
recycle, and entered a total shutdown phase. In 1984, a majority ownership interest was acquired
by Union Carbide Corporation's ("UCC") Metals Division which later became Umetco Minerals
Corporation ("Umetco"), a wholly-owned subsidiary of UCC. This partnership continued until
May 26, 1994 when EFN reassumed complete ownership. In May of I 997, Denison (then named
International Uranium (USA) Corporation) and its affiliates purchased the assets ofEFN and is the
cutTent owner of the facility. Throughout this Plan, the names Denison and ISA are used
interchangeably.
2.1. I Min and Tailings Management Facility
11:'.USERSiWMRCI'LA)\!'.SECT02,RPT\Jullc 2010
Page 2-2
Revision 3.2
Denison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
The Source Materials License Application for the White Mesa Mill was submitted to NRC on
February 8, 1978. Between that date and the date the first ore was fed to the mill grizzly on May
6, 1980, several actions were taken including: increasing mill design capacity, pe1l11it issuance
fi-om the United States Environmental Protection Agency ("EPA") and the State of Utah,
archeological clearance for the Mill and tailings areas, and an NRC pre-operational inspection on
May 5,1980.
Construction on the tailings area began on August I, 1978 with the movement of earth from the
area of Cell 2. Cell 2 was completed on May 4, 1980, Cell I on June 29, 1981, and Cell 3 on
September 2, 1982. In January of 1990 an additional cell, designated Cell 4A, was completed and
initially used solely for solution storage and evaporation. Cell 4A was only used for a shOlt
period of time and then taken out of service because of concerns about the synthetic lining system.
IN 2007, Cell 4A was retrofitted with a new State of Utah approved lining system and was put
back into service in October of 2008. Cell 4B construction was authorized by License
Amendment No.4, issued on June 17, 2010, and the cell is currently under construction.
2.2 Facility Operations
In the following subsections, an overview of mill operations and operating periods are followed by
descriptions of the operations of the mill circuit and tailings management facilities.
2.2.1 Operating Periods
The Mill was operated by EFN from the initial start-up date of May 6, 1980 until the cessation of
operations in 1983. Umetco, as per agreement between the parties, became the operator of record
on January 1, 1984. The Mill was shut down during all of 1984. The Mill operated at least part
of each year from 1985 through 1990. Mill operations again ceased during the years of 1991
11:IUSERS\ WM!l.CI'Li\)\"SECT02. RI'T'Junc 20 I 0
Page 2-3
Revision 3.2
Denison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
through 1994. EFN reacquired sole ownership on May 26, 1994 and the mill opcrated again
during 1995 and 1996. After acquisition of the Mill by Denison and its affiliates several local
mines were restarted and the Mill processed conventional ores during 1999 and early 2000. With
the resurgence in uranium and vanadium process in 2003, Denison reopened several area mines
and again began processing uranium and vanadium ores in April of 2008. Mill operations were
suspended in 2009, and resumed in March of20l O. Typical employment figures for the Mill are
110 during uranium-only operations and 140 during uranium/vanadium operations.
Commencing in the early 1990's through today, the Mill has processed altel11ate feed materials
from time to time when the Mill has been processing conventional ores. Altel11ate feed materials
are uranium-bearing materials other than conventionally-mined uranium ores. The Mill installed
an alternate feed circuit in 2009 that allows the Mill to process certain altel11ate feed materials
simultaneously with conventional ores.
11:\USERS\\VMRCI'LAN'SECT02.RPT\JHn~ 20 I 0
2.2.2 Mill Circuit
Page 2-4
Revision 3.2
Denison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
While originally designed for a capacity of 1,500 dry tons per day (dtpd.), the Mill capacity was
boosted to the present rated design of 1980 dtpd. prior to commissioning.
The mill uses an atmospheric hot acid leach followed by counter current decantation ("CCD").
This in turn is followed by a clarification stage which precedes the solvent extraction ("SX")
circuit. Kerosene containing iso-decanol and tertiary amines extract the uranium and vanadium
from the aqueous solution in the SX circuit. Salt and soda ash are then used to strip the uranium
and vanadium from the organic phase.
After extraction of the uranium values from the aqueous solution in SX, uranium is precipitated
with anhydrous ammonia, dissolved, and re-precipitated to improve product quality. The
resulting precipitate is then washed and dewatered using centrifuges to produce a final product
called "yellowcake." The yellowcake is dried in a multiple health dryer and packaged in drums
weighing approximately 800 to 1 ,000 Ibs. for shipping to converters.
After the uranium values are stripped from the pregnant solution in SX, the vanadium values are
transferred to tertiary amines contained in kerosene and concentrated into an intennediate product
called vanadium product liquor ("VPL"). An intennediate product, ammonium metavanadate
("AMV"), is precipitated from the VPL using ammonium sulfate in batch precipitators. The
AMV is then filtered on a belt filter and, if necessary, dried. Nonnally, the AMV cake is fed to
fusion furnaces when it is converted to the mill's primary vanadium product, V20 S tech flake,
commonly called "black flake."
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The same basic process steps used for the recovery of uranium from conventional ores are used for
the recovery of uranium from altemate feed materials, with some variations depending on the
patticular altemate feed material.
The mill processed 1,511,544 tons of ore and other materials from May 6, 1980 to February 4,
1983. During the second operational period from October 1,1985 through December 7,1987,
1,023,393 tons of conventional ore were processed. During the third operational period from July
1988 through November 1990, 1,015,032 tons of conventional ore were processed. During the
fourth operational period from August 1995 through January 1996, 203,317 tons of conventional
ore were processed. In the fifth operational period fi'om May 1996 tlu'ough September 1996, the
Mill processed 3,868 tons of calcium fluoride altemate feed matetial. From 1997 (0 early 1999"
the Mill processed 58,403 tons from several additional feed stocks.
With rising uranium prices in the late 1990's, company mines were reopened in 1997, and 87,250
tons of conventional ore were processed in 1999 and early 2000. In 2002 and 2003, the Mill
processed 266,690 tons of altemate feed material from govemment cleanup projects. An
additional 40,866 tons of altemate feed materials were processed in 2007. From April 2008
through May 2009 the Mill processed an additional 184,795 tons of conventional ore.
Inception to date material processed through May 2009 totals 4,128,468 tons. This total is for all
processing periods combined.
2.2.3 Tailings Management Facilities
Tailings produced by the mill typically contain 30 percent moisture by weight, have an in-place
dry density of86.3 pounds per cubic foot (Cell 2), have a size distribution with a predominant -325
mesh size fraction, and have a high acid and flocculent content. Tailings from altemate feed
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materials that are similar physically to conventional ores, which comprise most of the (ons of
alternate feed materials processed to date at the Mill, are similar to the tailings for conventional
ores. Tailings from some of the higher grade, lower volume alternate feed materials may vary
somewhat from the tailings from conventional ores, plimarily in moisture and density content.
The tailings facilities at White Mesa currently consist offour cells as follows:
• Cell I, constructed with a 30-millimeter (ml) PVC earthen-covered liner, is used for the
evaporation of process solution (Cell I was previously referred to as Cell 1-1, but is
now refelTed to as Cell 1);
• Cell 2, constructed with a 30-millimeter (ml) PVC earthen-covered liner, is used for the
storage of barren tailings sands. This Cell is full and has been partially reclaimed;
• Cell 3, constructed with a 30-millimeter (ml) PVC earthen-covered liner, is used for the
storage of barren tailings sands and solutions. This cell is partially filled and has been
partially reclaimed; and
• CeIl4A, constructed with a geosynthetic clay liner, a 60 Millimeter (mil) HDPE liner, a
300 mil HDPE geonet drainage layer, a second 60 mil HDPE liner, and a slimes drain
network over the entire cell bottom. This cell was placed into service in October of
2008.
• CeIl4B, will be constructed with a geosynthetic clay liner, a 60 Millimeter (mil) HDPE
liner, a 300 mil HDPE geonet drainage layer, a second 60 mil HDPE liner, and a slimes
drain network over the entire cell bottom. This cell will be constructed during the
2010 construction season.
•
•
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Total estimated design capacity of Cells 2, 3, and 4A is approximately six million (mm) tons.
Figures 1.5-4 and 1.5-5 show the locations of the tailings cells.
Denison has submitted an application to the Executive Secretary to amend the License and GWDP
to authorize the construction of tailings Ce1l4B, which will be located adjacent to Ce1l4A and will
provide approximately two million additional tons of tailings capacity. That application was
approved by the Executive Secretary on June 17,2010.
2.2.3.1 Tailings Management
Constructed in shallow valleys or swale areas, the lined tailings facilities provide storage below the
existing grade and reduce potential exposure. Because the cells are separate and distinct,
individual tailings cells may be reclaimed as they are filled to capacity. This phased reclamation
approach minimizes the amount of tailings exposed at any given time and reduces potential
exposure to a minimum.
Slurry disposal has taken place in Cells 2, 3 and 4A. Tailings placement in Cell 2 and Cell 3 was
accomplished by means of the final grade method, described below.
The final grade method used in Cell 2 and Cell 3 calls for the slurry to be discharged until the
tailings surface comes up to final grade. The discharge points are set up in the east end of the cell
and the final grade surface is advanced to the slimes pool area. Coarse tailings sand from the
discharge points are graded into low areas to reach the final disposal elevation. When the slimes
pool is reached, the discharge points are then moved to the west end of the cell and worked back to
the middle. An advantage to using the final grade method is that maximum beach stability is
achieved by (l) allowing water to drain from the sands to the maximum extent, and (2) allowing
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coarse sand deposition to help provide stable beaches. Another advantage is that radon release
and dust prevention measures (through the placement of the initial layer of the final cover) are
applied as expeditiously as possible.
SIUlTY disposal in Cell 4A is from several pre-detennined discharge points located around the
north and east sides of the cell. Slurry discharge is only allowed on skid pads, or protective
HDPE sheets, to prevent damage to the synthetic lining system. Once tailings solids have reach
the maximum elevation around the perimeter of the cell, discharge points can be moved toward the
interior of the cell. Slurry disposal in Cell4B will be conducted in the same manner as Ce1l4A.
2.2.3.2 Liquid Management
As a zero-discharge facility, the White Mesa Mi1l must evaporate all of the liquids utilized during
processing. This evaporation takes place in three (3) areas:
• Cell I, which is used for solutions only;
• Cell 3, in which tailings and solutions exist;
• Cell 4A, in which tailings and solutions exist, and
• Cell 4B after construction is complete.
The original engineering design indicated a net water gain into the cells would occur during Mill
operations. As anticipated, this has been proven to be the ease. In addition to natural
evaporation, spray systems have been used at various times to enhance evaporative rates and for
dust control. To minimize the net water gain, solutions are recycled from the active tailings cells
to the maximum extent possible. Solutions from Cells I, 3, and 4A are brought back to the CCD
circuit where metallurgical benefit can be realized. Cell 4B will be operated in the same manner
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as Ce1l4A. Recycle to other parts of the mill circuit are not feasible due to the acid content of the
solution.
2.3 Monitoring Programs
Operational monitoring is defined as those monitoring activities that take place only during
operations. This is contrasted with environmental monitoring, which is perf0l111ed whether or not
the mill is in operation.
2.3.1 Monitoring and Reporting Under the Mill's GWDP
2.3.1.1 Groundwater Monitoring
a) Plugged and Excluded Wells
Wells MW-6, MW-7, and MW-8 were plugged because they were in the area of Cell 3, as was
MW-13, in the Ce1l4A area. Wells MW-9 and MW-IO are dry and have been excluded from the
monitoring program. MW-16 is dry and has been plugged as part of the tailings Cell 4B
construction.
b) Groundwater Monitoring at the Mill Prior to Issuance of the GWDP
At the time of renewal of the License by NRC in March, 1997 and up until issuance of the GWDP
in March 2005, the Mill implemented a groundwater detection monitoring program to ensure
compliance to 10 CFR Part 40, Appendix A, in accordance with the provisions of the License.
The detection monitoring program was in accordance with the report entitled, Points of
Compliance, White Mesa Uranium Mill, prepared by Titan Environmental Corporation, submitted
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by letter to the NRC dated October S, 1994 (Titan, 1994b). Under that program, the Mill sampled
monitoring wells MW-S, MW-11, MW-12, MW-14, MW-1S and MW-17, on a quarterly basis.
Samples were analyzed for chloride, potassium, nickel and uranium, and the results of such
sampling were included in the Mill's Semi-Annual Effluent Monitoring RepOlis that were filed
with the NRC up until August 2004 and with the DRC subsequent thereto.
Between 1979 and 1997, the Mill monitored up to 20 constituents in up to 13 wells. That program
was changed to the Points of Compliance Program in 1997 because NRC had concluded that:
• The Mill and tailings system had produced no impacts to the perched zone or deep
aquifer; and
• The most dependable indicators of water quality and potential cell failure were
considered to be chloride, nickel, potassium and natural uranium.
c) Issuance of the GWDP
On March 8, 200S, the Executive Secretary issued the GWDP, which includes a groundwater
monitoring program that supersedes and replaces the groundwater monitoring requirements set out
in the License. Groundwater monitoring under the GWDP commenced in March 200S, the
results of which are included in the Mill's Quarterly Groundwater Monitoring Reports that are
filed with the Executive Secretary.
d) CUlTent Ground Water Monitoring Program at the Mill Under the GWDP
The current groundwater monitoring program at the Mill under the GWDP consists of monitoring
at 22 point of compliance monitoring wells: MW-l, MW-2, MW-3, MW-3A, MW-S, MW-11,
MW-12, MW-14, MW-1S, MW-17, MW-18, MW-19, MW-23, MW-24, MW-2S, MW-26,
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MW-27, MW-28, MW-29, MW-30, MW-31 and MW-32. The locations of these wells are
indicated on Figure 1.5-2.
Part I.E.l.(c) of the GWDP requires that each point of compliance well must be sampled for the
following constituents:
Table 2.3-1
Grouudwater Monitoring Constituents Listed in Table 2 of the GWDP
Nutrients:
Ammonia (as N)
Nitrate & Nitrite (as N)
Heavy Metals:
Arsenic
Beryllium
Cadmium
Chromium
Cobalt
Copper
Iron
Lead
Manganese
Mercury
Molybdenum
Nickel
Selenium
Silver
Thallium
Tin
Uranium
Vanadium
Zinc
Radiologies:
Gross Alpha
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Volatile Organic Compounds:
Acetone
Benzene
2-Butanone (MEK)
Carbon Tetrachloride
Chloroform
Chloromethane
Dichloromethane
Naphthalene
Tetrahydrofuran
Toluene
Xylenes (total)
Others:
Field pH (S.U.)
Fluoride
Chloride
Sulfate
TDS
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Further, Part I.E.l.(c) of the GWDP, requires that, in addition to pI-I, the following field parameters
must also be monitored:
• Depth to groundwater
• Temperature
• Tubidityr
• Specific conductance,
and that, in addition to chloride and sulfate, the following general organics must also be monitored:
• Carbonate, bicarbonate, sodium, potassium, magnesium, calcium, and total anions and
cations.
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Sample fi'equency depends on the speed of ground water flow in the vicinity of each well. Parts
I.E.1 (a) and (b) of the GWDP provide that quarterly monitoring is required for all wells where
local groundwater average linear velocity has been found by the Executive Secretary to be equal to
or greater than 10 feet/year, and semi-annual monitoring is required where the local groundwater
average linear velocity has been found by the Executive Secretary to be less than 10 feet/year.
Based on these criteria, quarterly monitoring is required at MW-II, MW-14, MW-2S, MW-26,
MW-30 and MW-31, and semi-annual monitoring is required at MW-I, MW-2, MW-3, MW-3A,
MW-S,MW-12,MW-IS,MW-17,MW-18,MW-19,MW-23,MW-24,MW-27,MW-28,MW-29
and MW-32.
2.3.1.2 Deep Aquifer
The culinary well (one of the supply wells) is completed in the Navajo aquifer, at a depth of
approximately 1,800 feet below the ground surface. Due to the fact that the deep confined aquifer
at the site is hydraulically isolated from the shallow perched aquifer, no monitoring of the deep
aquifer is required under the GWDP.
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2.3.1.3 Seeps and Springs
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Pursuant to Part I.H.8 of the GWDP, Denison has a Sampling PlanjiJr Seeps and Springs in the
Vicinity of the White Mesa Uranium Mill, Revision: 0, March 17,2009 (the "SSSP") that requires
the Mill to perform groundwater sampling and analysis of all seeps and springs found
downgradient or lateral gradient from the tailings cells.
Under the SSSP, seeps and springs sampling is conducted on an annual basis between May I and
July 15 of each year, to the extent sufficient water is available for sampling, at five identified seeps
and springs near the Mill. The sampling locations were selected to correspond with those seeps
and springs sampled for the initial Mill site characterization performed in the 1978 ER, plus
additional sites located by Denison, the BLM and Ute Mountain Ute Indian Tribe representatives.
Samples are analyzed for all ground water monitoring parameters found in Table 2.3-1 above.
The laboratory procedures utilized to conduct the analyses of the sampled parameters are those
utilized for groundwater sampling. In addition to these laboratory parameters, the pH,
temperature and conductivity of each sample will be measured and recorded in the field.
Laboratories selected by Denison to perfOlID analyses of seeps and springs samples will be
required to be certified by the State of Utah in accordance with UAC R317-6-6.12.A.
The seeps and springs sampling events will be subject to the Mill's QAP, unless otherwise
specifically modified by the SSSP to meet the specific needs of this type of sampling.
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2.3.1.4 Discharge Minimization Technologv and Best Available Technology Standards and
Monitoring
2.3.1.4.1 General
Part I.D. of the GWDP sets out a number of Discharge Minimization Technology ("DMT") and
Best Available Technology ("BAT") standards that must be followed. Part I.E. of the GWDP sets
out the Ground Water Compliance and Technology Perfonnance Monitoring requirements, to
ensure that the DMT and BAT standards are met. These provisions of the GWDP, along with the
White Mesa Mill Tailings Management System and Discharge Minimization (DM1) Monitoring
Plan, 9/08 Revision: Denison-6 (the "DMT Plan"), the Cel! 4A BAT Monitoring, Operations and
Maintenance Plan and other plans and programs developed pursuant to such Parts of the GWDP,
set out the methods and procedures for inspections of the facility operations and for detecting
failure of the system.
In addition to the programs discussed above, the following additional DMT and BAT performance
standards and associated monitoring are required under Parts I.D and I.E. of the GWDP
b) Tailings Cell Operation
Part I.D.2 of the GWDP provides that authOlized operation and maximum disposal capacity in
each of the existing tailings Cells, I, 2 and 3 shall not exceed the levels authorized by the License
and that under no circumstances shall the fi'eeboard be less than three feet, as measured from the
top of the flexible membrane liner ("FML"). Part I.E.7(a) of the GWDP requires that the
wastewater pool elevations in Cells I and 3 must be monitored weekly to ensure compliance with
the maximum wastewater elevation criteria mandated by Condition 10.3 of the License.
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Pali I.D,2 further provides that any modifications by Denison to any approved engineering design
parameter at these existing tailings cells requires prior Executive Secretary approval, modification
of the GWDP and issuance of a construction permit.
c) Slimes Drain Monitoring
Part I.D,3(b)(1) of the GWDP requires that Denison must at all times maintain the average
wastewater head in the slimes drain access pipe to be as low as reasonably achievable (ALARA) in
each tailings disposal cell, in accordance with the approved DMT Plan, Compliance will be
achieved when the average annual wastewater recovery elevation in the slimes drain access pipe,
detennined pursuant to the currently approved DMT Plan meets the conditions in Equation
specified in Pati I.D,3(b)(1) of the GWDP,
Part I.E,7(b) of the GWDP requires that Denison must monitor and record monthly the depth to
wastewater in the slimes drain access pipes as described in the currently approved DMT Plan at
Cell 2, and upon commencement of de-watering activities, at Cell 3, in order to ensure compliance
with Part LD,3(b)(I) of the GWDP,
d) Maximum Tailings Waste Solids Elevation
Part I.D,3(c) of the GWDP requires that upon closure of any tailings cell, Denison must ensure that
the maximum elevation of the tailings waste solids does not exceed the top of the FML.
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e) Wastewater Elevation in Roberts Pond
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Pmi I.D.3(e) of the GWDP requires that Roberts Pond be operated so as to provide a minimum
2-foot freeboard at all times, and that under no circumstances will the water level in the pond
exceed an elevation of 5,624 feet above mean sea level. Part I.D.3(e) also provides that in the
event the wastewater elevation exceeds this maximum level, Denison must remove the excess
wastewater and place it into containment in Cell! within 72 hours of discovery.
Part I.E.7(c) of the GWDP requires that the wastewater level in Roberts Pond must be monitored
and recorded weekly, in accordance with the cUl1'ently approved DMT Plan, to determine
compliance with the DMT operations standard in Part I.D.3(e) of the GWDP;
f) Inspection of Feedstock Storage Area
Part I.D.3(f) of the GWDP requires that open-air or bulk storage of all feedstock materials at the
Mill facility awaiting Mill processing must be limited to the eastern portion of the Mill site (the
"ore pad") described by the coordinates set out in that Part of the GWDP, and that storage of
feedstock materials at the facility outside of this defined area, must meet the requirements of Pmi
I.D.l! of the GWDP. Part I.D.l! requires that Denison must store and manage feedstock
matelials outside the defined ore storage pad in accordance with the following minimum
perfonl1ance requirements:
(i) Feedstock materials will be stored at all times in water-tight containers, and
(ii) Aisle ways will be provided at all times to allow visual inspection of each and every
feedstock container, or
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(iii) Each and every feedstock container will be placed inside a water-tight overpack
prior to storage, or
(iv) Feedstock containers shall be stored on a hardened surface to prevent spillage onto
subsurface soils, and that conforms with the following minimum physical
requirements:
A. A storage area composed of a hardened engineered surface of asphalt or
concrete, and
B. A storage area designed, constructed, and operated in accordance with
engineering plans and specifications approved in advance by the Executive
Secretary. All such engineering plans or specifications submitted shall
demonstrate compliance with Part I.DA of the GWDP, and
C. A storage area that provides containment berms to control stonnwater run-on
and run-off, and
D. StOlIDwater drainage works approved in advance by the Executive Secretary, or
(v) Other storage facilities and means approved in advance by the Executive Secretary.
Part I.E.7(d) of the GWDP requires that Denison conduct weekly inspections of all feedstock
storage areas to:
(i) Confirm that the bulk feedstock materials are maintained within the approved
feedstock storage area specified by Part I.D.3(f) of the GWDP; and
(ii) Verify that all alternate feedstock materials located outside the approved feedstock
storage area are stored in accordance with the requirements found in Part l.D.!!
of the GWDP.
Part l.E.7(f) further provides that Denison must conduct weekly inspections to verify that each
feed material container complies with the requirements of Part J.D.!! of the GWDP.
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The Mill's Standard Operating Procedure under the License for inspection of the Mill's ore pad is
contained in Section 3.3 of the DMT Plan.
g) Monitor and Maintain Inventory of Chemicals
Part I.D.3(g) of the GWDP requires that for all chemical reagents stored at existing storage
facilities and held for use in the milling process, Denison must provide secondary containment to
capture and contain all volumes of rcagent(s) that might be released at any individual storage area.
Response to spills, cleanup thereof, and required reporting must comply with the provisions of the
Mill's Emergency Response Plan, which is found in the Mill's Stormwater Best Management
Practices Plan, Revision 1.3; June 12, 2008 (a copy of which is included as Appendix C), as
stipulated by Parts l.D.l 0 and l.H.1 6 of the GWDP. Part I.D.3(g) further provides that for any
new construction of reagent storage facilities, such secondary containment and control must
prevent any contact of the spilled or otherwise released reagent or product with the ground surface.
Part I.E.9 of the GWDP requires that Denison must monitor and maintain a current inventory of all
chemicals used at ti1e facility at rates equal to or greater than 100 kg/yr. This inventory must be
maintained on-site, and must include:
(iii) Identification of chemicals used in the milling process and the on-site laboratory;
and
(iv) Determination ofvolumc and mass of each raw chemical currently held in storage
at the facility.
2.3.1.5 BAT Performance Standards for Ce1l4A . .
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a) BAT Operations and Maintenance Plan
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Part l.D.6 of the GWDP provides that Denison must operate and maintain Cell 4A so as to prevent
release of wastewater to groundwater and the environment in accordance with the Mill's Celi4A
BATMonitoring, Operations and Maintenance Plan, pursuant to Part I.H.19 of the GWDP. The
Mill's Ce1l4A BAT Monitoring, Operations and Maintenance Plan, 09/08 Revision: Denison 1.3
includes the following perfonnance standards:
(i) The fluid head in the leak detection system shall not exceed 1 foot above the lowest
point in the lower membrane liner;
(ii) The leak detection system maximum allowable daily leak rate shall not exceed
24,160 gallons/day;
(iii) After Denison initiates pumping conditions in the slimes drain layer in Cell 4A,
Denison will provide continuous declining fluid heads in the slimes drain layer, in a
manner equivalent to the requirements found in Part I.D.3(b) for Cells 2 and 3; and
(iv) Under no circumstances shall the freeboard be less than 3-feet in Cell 4A, as
measured from the top of the FML.
b) Implementation of Monitoring Requirements Under the BAT Operations and
Maintenance Plan
The Cell 4A BAT Monitoring, Operations and Maintenance Pian also requires Denison to perfonn
the following monitoring and recordkeeping requirements. Similar monitoring and
recordkeeping requirements will be included with the Cell 4B BAT Plan:
(i) Weekly Leak Detection System (LDS) Monitoring -including:
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A. Denison must provide continuous operation of the leak detection system
pumping and monitoring equipment, including, but not limited to, the
submersible pump, pump controller, head monitoring, and flow meter
equipment approved by the Executive Secretary. Failure of any pumping or
monitoring equipment not repaired and made fully operational within 24-hours
of discovery shall constitute failure of BAT and a violation of the GWDP;
B. Denison must measure the fluid head above the lowest point on the secondary
FML by the use of procedures and equipment approved by the Executive
Secretary. Under no circumstance shall fluid head in the leak detection system
sump exceed a I-foot level above the lowest point in the lower FML on the cell
floor. For purposes of compliance monitoring this I-foot distance shall equate
to 2.28 feet above the leak detection system transducer;
C. Denison must measure the volume of all fluids pumped from the leak detection
system. Under no circumstances shall the average daily leak detection system
flow volume exceed 24,160 gallons/day; and
D. Denison must operate and maintain wastewater levels to provide a 3-foot
Minimum of vertical freeboard in tailings Cell 4A. Such measurements must
be made to the nearest 0.1 foot.
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(ii) Slimes Drain Recovery Head Monitoring
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Immediately after the Mill initiates pumping conditions in the Cell 4A slimes drain system,
monthly recovery head tests and fluid level measurements will be made in accordance with the
requirements of Parts I.D.3 and I.E.7(b) of the GWDP and any plan approved by the Executive
Secretary.
2.3.1.6 Storm water Management and Spill Control Requirements
Part I.D.10 of the GWDP requires that Denison will manage all contact and non-contact
stormwater and control contaminant spills at the facility in accordance with the Mill's stormwater
best management practices plan. The Mill's Stormwater Best Management Practices Plan,
Revision 1.3: June 12, 2008 (a copy of which is included as Appendix C) includes the following
provisions:
a) Protect groundwater quality or other waters of the state by design, construction, andlor
active operational measures that meet the requirements of the Ground Water Quality
Protection RC!,'lllations found in UAC R317-6-6.3(G) and R317-6-6.4(C);
b) Prevent, control and contain spills of stored reagents or other chemicals at the Mill site;
c) Cleanup spills of stored reagents or other chemicals at the Mill site immediately upon
discovery; and
d) Report reagent spills or other releases at the Mill site to the Executive Secretary in
accordance with UAC 19-5-I 14.
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2.3.1.7 Tailings and Slimes Drain Sampling
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Part I.E.8 of the GWDP requires that, on an annual basis, Denison must collect wastewater quality
samples from each wastewater source at each tailings cell at the facility, including surface
impounded wastewaters, and slimes drain wastewaters, pursuant to the Mill's Tailings and Slimes
Drain Sampling Program, Revision 0, November 20, 2008 (the "WQSP"). All such sampling
must be conducted in August of each calendar year.
The pUlvose of the WQSP is to characterize the source tenn quality of all tailings cell wastewaters,
including impounded wastewaters or process waters in the tailings cells, and wastewater or
leaehates collected by intemal slimes drains. The WQSP requires:
• Collection of samples from the pond area of each active cell and the slimes drain of each
cell that has commenced de-watering activities;
• Samples of tailings and slimes drain material will be analyzed at an offsite contract
laboratory and subjected to the analytical parameters included in Table 2 of the GWDP
(see Table 2.3-1 above) and general inorganics listed in PaJi I.E. 1 (d)(2)(ii) of the GWDP,
as well as semi-volatile organic compounds;
• A detailed desctiption of all sampling methods and sample preservation techniques to be
employed;
• The procedures utilized to conduct these analyses will be standard analytical methods
utilized for groundwater sampling and as shown in Section 8.2 of the Mill's QAP;
• The contracted laboratory will be certified by the State of Utah in accordance with UAC
R317-6-6.12A; and
• 30-day advance notice of each annual sampling event must be given, to allow the
Executive Secretary to collect split samples of all tailings cell wastewater sources.
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Denison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
The tailings and slimes drain sampling events are subject to the Mill's QAP, unless otherwise
specifically modified by the WQSP to meet the specific needs of this type of sampling.
2.3.2 Monitoring and Inspections Required Under the License
2.3.2.1 Environmental Monitoring
The environmental monitoring program is designed to assess the effect of Mill process and
disposal operations on the unrestricted environment. Delineation of specific equipment and
procedures is presented in the Mill's Environmental Protection Manual, included as Appendix A
to the 2007 License Renewal Application.
c) Ambient Air MonitOling
(i) Ambient Particulate
Airborne radionuclide particulate sampling is performed at five locations, termed BHV-l, BHV-2,
BHV-4, BHV-5 and BHV-6. With the approval of the NRC and effective November, 1995,
BHV-3 was removed from the active air particulate monitoring program. At that time, the Mill
proposed (and NRC detennined) that a sufficient air monitoring data base had been compiled at
station BHV-3 to establish a representative airborne particulate radionuclide background for the
Mill. BHV -6 was installed by the Mill at the request of the White Mesa Ute Community. This
station began operation in July of 1999 and provides airborne particulate inforn1ation in the
southerly direction between the Mill and the White Mesa Ute Community. Figure 2.3-1 shows
the locations of these air particulate monitoring stations.
I !:\USERS\WMRCPLAN'SECTO~,RJ>T\JUIIC 20 I ()
Insert Fig 2.3-1 locations of air particulate stations
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White Mesa Mill Reclamation Plan
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White Mesa Mill Reclamation Plan
The present sampling system consists of high volume particulate samplers utilizing mass flow
controllers to maintain an air flow rate of approximately 32 standard cubic feet per minute.
Samplers are operated continuously with a goal for on-stream operating period at ninety percent.
Filter rotation is weekly with quarterly site compo siting for pmiiculate radionuclide analysis.
Analysis is done for U-natural, Th-230, Ra-226, and Pb-21 O.
Sec Section 3.13.1.7(a) of the 2007 ER for a summary of historic monitoring results for airborne
particulate.
(ii) Ambient Radon
With the approval of the NRC, Radon-222 monitoring at the BHV stations was discontinued in
1995, due to the unreliability of monitoring equipment available at that time to detect the new 10
CFR standard of 0.1 pCi/l. From that time until the present, the Mill demonstrated compliance
with the requirements of R313-15-301 by calculation authorized by the NRC in September 1995
and as contemplated by R313-15-302 (2) (a).
This calculation was perfonned by use of the MILDOS code for estimating environmental
radiation doses for uranium recovery operations (Strenge and Bender 1981) in 1991 in support of
the Mill's 1997 license renewal and more recently in 2007 in support of the 2007 License Renewal
Application, by use of the updated MILDOS AREA code (Argonne 1998). The analysis under
both the MILDOS and MILDOS AREA codes assumed the Mill to be processing high grade
Arizona Strip ores at full capacity, and calculated the concentrations of radioactive dust and radon
at individual receptor locations around the Mill. Specifically, the modeling under these codes
assumed the following conditions:
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• 730,000 tons of ore per year
• Average grade of 0.53% U308
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White Mesa Mill Reclamation Plan
• Yellowcake production of 4,380 tons ofU308 per year (8.8 million pounds U30 8 per year).
Based on these conditions, the MILDOS and MILDOS AREA codes calculated the combined total
effective dose equivalent from both air particulate and radon at the cutTent nearest residence
(approximately 1.2 miles north of the Mill), i.e., the individual member of the public likely to
receive the highest dose from Mill operations, as well as at all other receptor locations, to be below
the ALARA goal of 10 mrem/yr for air particulate alone as set out in R313-15-101(4). Mill
operations are constantly monitored to ensure that operating conditions do not exceed the
conditions assumed in the above calculations. If conditions are within those assumed above,
radon has been calculated to be within regulatory limits. If conditions exceed those assumed
above, then further evaluation will be perfol111ed in order to ensure that doses to the public
continue to be within regulatory limits. Mill operations to date have never exceeded the License
conditions assumed above.
In order to determine if detection equipment has improved since 1995, the Mill has, commencing
with the first quarter of2007, re-instituted direct measurements of radon at the five air particulate
monitoring locations currently utilized for air particulate sampling. The reliability of this data is
cUITently under review by Denison.
d) External Radiation
TLD badges, as supplied by Landauer, Inc., or equivalent, are utilized at BHV-I, BHV-2, BHV-3,
BHV-4, B1-lV-5 and BHV-6 to determine ambient external gamma exposures (see Figure 2.3-1).
System quality assurances are detel111ined by placing a duplicate monitor at one site continuously.
Exchanges of TLD badges are on a quarterly basis. Badges consist of a minimum of five TLD
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chips. Measurements obtained £i'om location BHV -3 have been designated as background due to
BHV-3 's remoteness from the Mill site (BHV-3 is located approximately 3.5 miles west of the
Mill site). For further procedural infonnation see Section 4.3 of the Mill's Environmental
Protection Manual, included as Appendix A to the 2007 License Renewal Application. See
Section 3.13.1.7(c) of the 2007 ER for a summary of historic monitoring results for external
radiation.
e) Soil and Vegetation
(i) Soil Monitoring
Soil samples from the top one centimeter of surface soils are collected annually at each ofBHV-l,
BHV-2, BHV-3, BHV-4 and BHV-5 (see Figure 2.3-1). A minimum of two kilograms of soil is
collected per site and analyzed for U-natural and Ra-226. For further procedural information see
Section 4.1 of the Mill's Environmental Protection Manual included as Appendix A to the 2007
License Renewal Application. See Section 3.13.1.7.1 of the 2007 ER for a summary of the
historic results for soil monitoring. The 2007 ER concludes that the results of sampling are low,
less than the unrestricted release limits.
(i) Vegetation Monitoring
Forage vegetation samples are collected three times per year from animal grazing locations to the
northeast (near BHV-I (the meteorological station)), northwest (to the immediate west of the site)
and southwest (by BHV-4) of the Mill site. Samples are obtained during the grazing season, in
the late fall, early spring, and in late spring. A minimum of three kilograms of vegetation are
submitted from each site for analysis of Ra-226 and Pb-21 O. For further procedure information
see Section 4.2 of the Mill's Environmental Protection Manual included as Appendix A to the
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2007 License Renewal Application. See Section 3.13.7(d) of the 2007 ER for a summary of the
historic results for vegetation monitoring. The 2007 ER concludes that the most recent results
indicate no increase in uptake ofRa-226 and Pb-21 0 in vegetation.
d) Meteorological
Meteorological monitoring is done at a site near BHV-I. The sensor and recording equipment are
eapable of monitoring wind veloeity and direction, i1'OIn which the stability classification is
calculated. Data integration duration is one-hour with hourly recording of mean speed, mean
wind direction, and mean wind stability (as degrees sigma theta).
The data from the meteorological station is retrieved monthly by down loading onto a Campbell
Scientific data module, or the equivalent. The data module is sent to an independent
meteorological contractor where the module is downloaded to a computer record, and the data is
cOITelated and presented in a Semi-Annual Meteorological Report.
Monitoring for precipitation consists of a daily log of precipitation using a standard NOAA rain
gauge, or the equivalent, installed near the administrative office, consistent with NOAA
specifications.
Windrose data is summmized in a fOl1nat compatible with MILDOS and UDAD specifications for
40 CFR 190 compliance. For fmiher procedural infol1nation see Section 1.3 of the Mill's
Environmental Protection Manual included as Appendix A to the 2007 License Renewal
Application. A windrose for the site is set out in Figure I. I-I.
e) Point Emissions
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Stack emission monitoring il'om yellowcake facilities follows EPA Method 5 procedures and
occurs on a qumterly basis, during operation of the facility. Particulate sampling is analyzed for
Unat on a quarterly basis and for Th-230, Ra-226, and Pb-21 0 on a semi-annual basis. Demister
and ore stack emission monitoring follows EPA Method 5 procedure on a semi-annual basis,
during operation of the facility. Particulate samples are analyzed for Unat, Th-230, Ra-226, and
Pb-210. Monitored data includes scrubber system operation levels, process feed levels,
particulate emission concentrations, isokinetic conditions, and radionuclide emission
concentrations. For further procedure infonnation see Section 1.4 of the Mill's Environmental
Protection Manual included as Appendix A to the 2007 License Renewal Application. Historic
stack emission data are summarized in Section 3.13.1.7(e) of the 2007 ER.
f) Surface Water Monitoring
Surface water monitoring is conducted at two locations adjacent to the Mill facility known as
Westwater Canyon and Cottonwood Creek. Samples are obtained annually fi'O!n Westwater and
quarterly from Cottonwood using grab sampling. For Westwater Creek, samples will be of
sediments if a water sample is not available. Field monitored parameters and laboratory
monitored parmneters are listed in Table 2.3-2. For further procedural information see Section
2.1 of the Mill's Environmental Protection Manual included as Appendix A to the 2007 License
Renewal Application. See Section 3.7.4 of the 2007 ER for a summary of the historic results for
surface water moni toring.
Table 2.3-2
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White Mesa Mill Reclamation Plan
Operational Phase Surface Water Monitoring Program
Monitoring Sites
Westwater Creek and Cottonwood Creek
Field Requirements
1. temperature C;
2. Specific Conductivity umhos at 25 C;
3. pH at 25 C;
4. Sample date;
5. Sample ID Code;
Vendor Laboratory Requirements
Semiannual* Quarterty
One gallon Unfiltered and Raw One gallon Unfiltered and Raw
One gallon Unfiltered, Raw and preserved to One gallon Unfiltered, Raw and Preserved to
pH <2 with HNO) pH <2 with HNO)
Total Dissolved Solids Total Dissolved Solids
Total Suspended Solids Total Suspended Solids
Gross Alpha
Suspended Un at
Dissolved Unat
Suspended Ra-226
Dissolved Ra-226
Suspended Th-230
Dissolved Th-230
:;;SemIaIUlUal sample must be taken a mllllmum of four months apart.
**AnnuaJ Westwater Creek sample is analyzed for semi-annual parameters.
Radionuclides and LLDs reported in f,Ci/ml
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2.3.2.2 Additional Monitoring and Inspections Required Under the License
Under the License daily, weekly, and monthly inspection reporting and monitoring are required by
NRC Regulatory Guide 8.31, Information Relevant to Ensuring that Occupational Radiation
I"xposures a/ Uranium Recovery Facilities will be As Low As is Reasonable Achievable, Revision
1, May 2002 ("Reg Guide 8.31 "), by Section 2.3 of the Mill's ALARA Program and by the DMT
Plan, over and above the inspections described above that are required under the GWDP. A copy
of the Mill's ALARA Program is included as Appendix 1 to the 2007 License Renewal
Application.
a) Daily Inspections
Three types of daily inspections are perfoJ1ned at the Mill under the License:
(i) Radiation Staff Inspections
Paragraph 2.3.1 of Reg. Guide 8.31 provides that the Mill's Radiation Safety Officer ("RSO") or
designated health physics technician should conduct a daily walk-through (visual) inspection of all
work and storage areas of the Mill to ensure proper implementation of good radiation safety
procedures, including good housekeeping that would minimize unnecessary contamination.
These inspections are required by Section 2.3.1 of the Mill's ALARA Program, and are
documented and on file in the Mill's Radiation Protection Office.
(ii) Operating Foreman Inspections
30 CFR Section 56.18002 of the Mine Safety and Health Administration regulations requires that a
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competent person designated by the operator must examine each working place at least once each
shift for conditions which may adversely affect safety or health. These daily inspections are
documented and on file in the Mill's Radiation Protection Office.
(iii) Daily Tailings Inspection
Paragraph 2.2 of the DMT Plan requires that during Mill operation, the Shift Foreman, or other
person with the training specified in paragraph 2.4 of the DMT Plan, designated by the RSO, will
perf 01111 an inspection of the tailings line and tailings area at least once per shift, paying close
attention for potential leaks and to the dischargcs from the pipelines. Observations by the
Inspector are recorded on the appropriate line on the Mill's Daily Inspection Data fonn.
b) Weekly Inspections
Three types of weekly inspections are perfonned at the Mill under the License:
(i) Weekly Inspection of the Mill Forms
Paragraph 2.3.1 of Reg. Guide 8.31 provides that the RSO and the Mill forcman should, and
Section 2.3.2 of the Mill's ALARA Program provides that the RSO and Mill foreman, or their
respective designees, shall conduct a weekly inspection of all Mill areas to observe general
radiation control practices and review required changes in procedures and equipment. Particular
attention is to be focused on areas where potential exposures to personnel might exist and in areas
of operation or locations where contamination is evident.
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(ii) Weekly Ore Storage Pad Inspection F0l111S
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Paragraph 3.3 of the DMT Plan requires that weekly feedstock storage area inspections will be
perfol111ed by the Radiation Safety Department, to confilm that the bulk feedstock materials are
stored and maintained within the defined area of the ore pad and that all alternate feed materials
located outside the defined ore pad area are maintained within water tight containers. The results
of these inspections are recorded on the Mill's Ore Storage/Sample Plant Weekly Inspection
Report.
(iii) Weekly Tailings and DMT Inspeetion
Paragraphs 3.1 and 3.2 of the DMT Plan require that weekly inspections of the tailings area and
DMT requirements be periol111ed by the radiation safety department.
c) Monthl y Reports
Two types of monthly reports are prepared by Mill staff:
(i) Monthly Radiation Safety Reports
At least monthly, the RSO reviews the results of daily and weekly inspections, including a review
of all monitoring and exposure data for the month and provides to the Mill Manager a monthly
report containing a written summary of the month's significant worker protection activities
(Section 2.3.4 of the Mill's ALARA Program).
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(ii) Monthly Tailings Inspection Reports
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White Mesa Mill Reclamation Plan
Paragraph 4 of the DMT Plan requires that a Monthly Inspection Data fonn be completed for the
monthly tailings inspection. This inspection is typically performed in the fourth week of each
month and is in lieu of the weekly tailings inspection for that week.
Mill staff also prepares a monthly summary of all daily, weekly, monthly and quarterly tailings
inspections.
d) Quarterly Tailings Inspections
Paragraph 5 of the DMT Plan requires that the RSO or his designee perform a quarterly tailings
inspection.
e) Annual Evaluations
The following annual evaluations are performed under the License, as set out in Section 6 of the
DMT Plan.
(i) Annual Technical Evaluation
An annual technical evaluation of the tailings management system must be perfonned by a
registered professional engineer (PE), who has experience and training in the area of geotechnical
aspects of retention structures. The technical evaluation includes an on-site inspection of the
tailings management system and a thorough review of all tailings records for the past year. The
Technical Evaluation also includes a review and summary of the annual movement monitor survey
(see paragraph (ii) below).
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All tailings cells and corresponding dikes are inspected for signs of erosion, subsidence, shrinkage,
and seepage. The drainage ditches are inspected to evaluate surface water control structures.
In the event tailings capacity evaluations were perfonned for the receipt of alternate feed material
during the year, the capacity evaluation forms and associated calculation sheets will be reviewed to
ensure that the maximum tailings capacity estimate is accurate. The amount of tailings added to
the system since the last evaluation will also be calculated to detemline the estimated capacity at
the time of the evaluation.
As discussed above, tailings inspection records consist of daily, weekly, monthly, and quarterly
tailings inspections. These inspection records are evaluated to detennine if any freeboard limits
are being approached. Records will also be reviewed to summarize observations of potential
concern. The evaluation also involves discussion with the Environmental and/or Radiation
Technician and the RSO regarding activities around the tailings area for the past year. During the
mmual inspection, photographs of the tailings area are taken. The training of individuals is also
reviewed as a part of the Annual Technical Evaluation.
The registered engineer obtains copies of selected tailings inspections, along with the monthly and
quarterly summaries of observations of concern and the corrective actions taken. These copies are
then included in the Annual Technical Evaluation Report.
The Annual Technical Evaluation Report must be submitted by September 1 st of every year to the
Directing Dam Safety Engineer, State of Utah, Natural Resources.
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(ii) Annual Movement Monitor Survey
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White Mesa Mill Reclamation Plan
A movement monitor survey is conducted by a licensed surveyor annually in accordance with
Conditon 11.3 of the License, approvedon June 17, 2010. The movement monitor survey consists
of surveying monitors along dikes 3-S, 4A-W, and 4A-S to detect any possible settlement or
movement of the dikes. The data generated hom this survey is reviewed and incorporated into
the Annual Technical Evaluation Report of the tailings management system.
(iii) Annual Leak Detection Fluid Samples
In the event solution has been detected in a leak detection system in Cells 1,2 or 3, a sample will be
collected on an annual basis. This sample will be analyzed according to the conditions set forth in
License Condition IlJ.C. The results of the analysis will be reviewed to detennine the origin of
the solution.
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2 0 FXISTING KAel! ITy
The fol lowing sections describe the construction history of the '''kite Mesa Mill; the Mmill and
Mmill tailings management facilities; Mmill operations including the Mmill circuit and tai lings
management; and both operational and environmental monitoring.
2.1 Facility Construction History
The White MesaMiII is a uranium/vanadium mill that was developed in the late 1970's by Energy
Fuels Nucl ear, Inc. (EFN) as an outlet for the many small mines that are located in the Colorado
Plateau and for the possibility of milling Arizona Strip orcs. At the ti me of its construction, it was
anticipated that high uranium prices would stimulate ore production. However, prices started to
decline about the same time as Mmil l operations commenced.
As uranium prices fell, producers in the region were affected and mine output declined. After
about two and one-half years, the Villite Mesa Mill ceased ore processing operations altogether,
began solution recycle, and entered a lotal shutdown phase. In 1984, a majority ownership
interest was acquired by Union Carbide Corporation's e UCC:) Melals Division which later
became Umetco Minerals Corporation e.Umetco:), a wholly-owned subsidiary of UCe. This
partnership continued unti l May 26, 1994 when EFN reassumed complete ownership. in May of
1997, Denison (then named Intemational Urani um 1..U.S.&Corporation) and its affiliates purchased
the assets of EFN and is the current owner of the facility. Throughout this Plan, the names
Denison and ISA are used interchangeably.
2.1.1 Mill and Tailings Management Facility
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The Source Materials License Application for the White Mesa Mill was submitted to tke U. S.
J!.,'tlele8F Regulet6f) CemmissieR (NRC) on February 8, 1978. Between th~ts date and the date
the first ore was fed to the mill grizzly on May 6, 1980, several actions were taken including:
increasing mill design capacity, permit issuance from the United States Environmental Protection
Agency (,"EPA") and the State of Utah, archeological cl earance for the Mmill and tailings areas,
and an NRC pre-operational inspection on May 5,1980.
Construction on the tailings area began on August 1, 1978 with the movement of earth from the
area of Cell 2. Cell 2 was completed on May 4, 1980, Cell I..J on June 29, 1981, and Cell 3 on
September 2, 1982. In January of 1990 an additional cell, designated Ce1l 4A, was completed and
pleeed int6 Hseinitially used solely for solution storage and evaporation. Cell 4A was only used
for a short period of time and then taken ou t of service because of concerns about the synthetic
lining system. IN 2007. Cell4A was retrofitted with a new State of Utah approved lining system
and was put back into service in October of 2008. Cell 48 construction was authorized by
License Amendment No.4 issued on June 17.2010. and the cell is currently under construction.
2.2 Faci lity Operations
In the following subsections, an overview of mill operations and operating periods are fo llowed by
descriptions of the operations of the mill circuit and tailings management fac ilities.
2.2.1 Operating Periods
The White Mesa Mill was operated by EFN from the initial start·up date of May 6, 1980 until the
cessation of operations in 1983. Umetco, as per agreement between the parties, became the
operator ofrecord on January 1, 1984. The White Mesa Mill was shut down during all of 1984.
The Mmill operated at least pal1 of each year from 1985 through 1990. Mill operations were
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again ceased during the years of 1991 through 1994. EFN reacquired sole ownership on May 26,
1994 and the mill operated again during 1995 and 1996. After acquisition of tile Mill by Denison
and its affiliates several local mines were restarted and the Mill processed conventional ores
during 1999 and early 2000. With the resurgence in uranium and vanadium process in 2003.
Denison reopened several area mines and again began processing uranium and vanadium ores in
April of 2008. Mill operations were suspended in 2009. and resumed in March 0[2010. Typical
employment figures for the Mmill are llQ8 during uranium-only operations and 140;8 during
uranium/vanadium operations.
Commencing in the early 1990's through today the Mill has processed alternate feed materials
from time to time when the Mill has been processing conventional ores. Alternate feed materials
are uranium-bearing materials other than conventionally-mined uranium ores. The Mill installed
an alternate feed circuit in 2009 that allows the Mill to process certain alternate feed materials
simultaneously with conventional ores.
2.2.2 Mill Circuit
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White Mesa Mill Reclamation Plan
While originally desi&'llCd for a capacity of J ,500 dry tons per day (dtpd.), the _Mmill capacity was
boosted to the present rated design of 1980 dtpd. prior to commissioning.
The mill uses an atmospheric hot acid leach followed by counter current decantation CCCD.J.
This in turn is followed by a clarification stage which precedes the solvent extraction t:SXJ
circuit. Kerosene containing iso-decanol and tertiary amines extract the uranium and vanadium
from the aqueous solution in the SX circuit. Salt and soda ash are then used to strip the uranium
and vanadium from the organic phase.
After extraction of the uranium values from the aqueous solution in SX, uranium is precipitated
with anhydrous ammonia, dissolved, and re-precipitated to improve product quality. The
resulting precipitate is then washed and dewatered using centrifuges to produce a final product
called "yellowcake." The yellowcake is dried in a multiple hearth dryer and packaged in drurns
weighing approximately 800 to J ,000 lbs. for shipping to converters.
After the uranium values are stripped from the pregnant solution in SX, the vanadium values are
transferred to tertiary amines contained in kerosene and concentrated into an intermediate product
called vanadium product liquOf CVPLJ. An intermediate product, ammonium meta vanadate
CAMV:J, is precipitated from the VPL using ammonium sulfate in batch precipitators. The
AMV is then filtered on a belt filter and, if necessary, dried. Normally, the AMV cake is fed to
fusion furnaces when it is converted to the mill's primary vanadium product, V20S tech flake,
commonly called "black flake."
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White Mesa Mill Reclamation Plan
The same basic process steps used for the recovery of uranium from conventional ores are used for
the recovery of uranium from alternate feed materials with some variations depending on the
particular alternate feed material.
The mill processed 1,511,544 tons of ore and other materials from May 6, 1980 to February 4,
1983. During the second operational period from October I, 1985 through December 7, 1987,
1,023,393 tons of conventional ore were processed. During the third operational period from July
1988 through November 1990, -1,015,032 tons of conventional ore were processed. During the
f0U11h operational period from August 1995 through January 1996, -203,3 17 tons of conventional
~were processed. lnJfhe fifth operational period from May 1996 through September 1996, the
Mill processed 3,868 tons of calcium fluoride alternate feed material. Siflee eafl) From 1997J.Q
early 1999., the Mmill has-processed 58,403 tons from several additional feed stocks.
With rising uranium prices in the late 1990's. company mines were reopened in 1997. and 87.250
tons of conventional are were processed in 1999 and early 2000. In 2002 and 2003 the Mill
processed 266.690 tons of alternate feed material from government cleanup projects. An
additional 40866 tons of alternate feed materials were processed in 2007. From April 2008
through May 2009 the Mill processed an additional 184.795 tons of conventional ore.
Inception to date material processed through April 1999May 2009 totals 3,815,5771,128.468 tons.
This total is for all processing periods combined.
2.2.3 Tailings Management Facilities
Tailings produced by the mill typically contain 30 percent moisture by weight, have an in-place
dry density of86.3 pounds per cubic fOOl (Cell 2), have a size distribution with a predominant -325
mesh size fraction, and have a high acid and flocculent content. Tailings from alternate feed
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materials that are similar nhysically to conventional ores. which comprise most of the tons of
alternate feed materials processed to date at the Mill are similar to the tailings for conventional
ores. Tailings from some of the higher grade. lower volume alternate feed materials may vary
somewhat from the tailings from conventional ores. primarily in moisture and density content.
The tailings facilities at White Mesa currently consist of four cells as follows:
_0 _-Cell 1, constructed with a 30-millimeter (ml) PVC earthen-covered liner, is used"· --
for the evaporation of process solution (Cell 1 was previously referred to as CellI-I.
but is now referred to as Cell 1 );!"
_0 _--Cell 2, constructed with a 30-millimeter (ml) PVC earthen-covered liner, is used
for the storage of barren tailings sands. This Cell is full and has been partially
reclaimed·
!.......-Cell 3, constructed with a 30-mi llimeter (ml) PVC earthen-covered liner, is used
for the storage of ban·en ta ilings sands and solutions. This cell is partially filled and
has been partially reclaimed; and
!.......-Cell 4A, constructed with a geosynthetic clay liner. a 60 Millimeter (mil) HOPE
liner. a 300 mil HOPE geonet drainage layer. a second 60 mil HOPE liner. and a slimes
drain network over the entire cell bottom. This cell was placed into service in October
• Cell4B will be constructed with a geosynthetic clay liner. a 60 Millimeter (mill HOPE
liner. a 300 mil HOPE geonet drainage layer a second 60 mil HOPE liner. and a slimes
drain network over the entire cell bottom. This cell will be constructed during the
2010 construction season.
°
• 4Q millimeter (ml) HOPE liner, is etifFentl) flet used.
formatted: lisl Paragraph, SUrleted + level:
1 + Aligned at: 0.5" + Indent at: 0.75"
Formatted: list Paragraph, Bulleted + level:
1 + Aligned at: 0.5" + Indent at: O. 7S~
Page 2-7
Revision Wl1
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White Mesa Mill Reclamation Plan
Total estimated design capacity of Cells 2, 3, and 4A is approximately six million (mm) et:tltie
yeMstons. Figures 1.54 and 1.5-5 show the locations of the tailings cells.
Denison has submitted an application to the Executive Secretary to amend the License and GWDP
to authorize the construction of tai lings Ce1l4B. which will be located adjacent to Cell4A and will
provide approximately two million additional tons of tailings capacity. That application was
approved by the Executive Secretary on June 17, 2010.
1;']:..3.:. ~ !qJ{i'.!.8.s}1(lI!n.8!'1If}I!l ______________________________________________ ---{ Formatted: Font: Italic
Constructed in shallow valleys or swale areas, the lined tailings facilities provide storage below the
existing grade and reduce potential exposure. Because the cell s are separate and distinct,
individual tailings cells may be reclaimed as they are filled to capacity. This phased reclamation
approach minimizes the amount of tailings exposed at any given time and reduces potential
exposure to a minimum.
Slurry disposal has taken place in Cells 2, 3 and 4A. Tailings placement in Cell 2 and Cell 3 was
accomplished by means of the final grade method described below.
The ~eFimeteF Eliseh8Fge methee iR\'el'/es settiRg tip eiseh8rge ~eiRts aFetiRe tHe east, ReftJ:~, 8Re
v, est betiRaaFies efthe eel I. This Fesults iH Ie .. east eis~asal at fiFst, felle f\ ee by higheF dis~esfl:l
eests tewafa tHe eHd ef the eell's life. The dtsetiw:fHage te tHis methed is that feelamatieR
aeti. ities eaHHet talte ~18ee uRtil HeaF lhe eHe Bf the eell's life. This disadl 8Ht8ge II as Feeegniletl
eml!eElle Ihe Eleo'e!epmeAleflhe HAe! gFftEle melhed.
Page 2-8
Revision ~3.2
l_eMn.~"""Denison Mines (USA) Corp.
White Mesa Mill Recl amation Plan
Sh::lff) Elis~es61 has tai(en "laee in 6eth Cells 2 BRd 3. Tails ~18eeffieflt aeeem"lishea in Cell 2 ... 85
by meaRS of the abeYe-deserieee J'erimeter diseharge mettles, .. ,hile in Cell 3 the Hnftl greae
metheEl, deseribed bele\,." hes beeR emfJle) eel.
The final grade method used in Cell 2 and Cell 3 calls for the slu rry to be discharged until the
tailings surface co mes up to final grade. The discharge points are set up in the east end of the cell
and the final grade surface is advanced to the slimes pool area. Coarse tailings sand from the
discharge points are graded into low areas to reach the final disposal elevation. When the slimes
pool is reached, the discharge points are then moved to the west end of the cell and worked back to
the middle. An advantage to using the final grade method is that maximum beach stabi lity is
achieved by (1) allowing water to drain from the sands to the maximum ex tent, and (2) allowing
coarse sand deposition to help provide stable beaches. Another advantage is that radon release
and dust prevention measures (through the placement of the initial layer of the final cover) are
appli ed as expeditiously as possible.
Slurry disposal in Cell 4A is from several pre-determined discharge points located around the
north and east sides of the cell. Slurry discharge is only allowed on skid pads. or protective
HDPE sheets to prevent damage to the synthetic lining system. Once tailings solids have reach
the maximum elevation around the perimeter of the cell discharge points can be moved toward the
interior of the cell. Slurry disposal in Cel14B will be conducted in the same manner as Ce114A.
I l_l.3.;~ bi!J!lij(!vJfl.'!(l$g/!UP!1 ______________________________________________ ; _ --( fOrmatted: Font Italic
As a zero-discharge facility, the White Mesa Mill must evaporate all of the liquids utilized during
processing. This evaporation takes place in t-we-three (3) areas:
_0 _--Cell 1, which is used for solutions only; .. - - -Formatted: list Paragraph, Bulleled + Level:
1 + Aligned at: 0.5" + Indent at: 0.75"
Page 2-9
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IHtemetieHol UfoHiumDenison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
~ -Cell 3, in which tailings and sol utions ex ist;
• CeIl4A. in which tailings and solutions exist. and
• Cell 48 after construction is complete.
The original engineerin g design indicated a net water gain into the cells would occur during Mmill
operations. As anticipated, this has been proven to be the case. I n addition to natural
evaporation, spray systems have been used at various times to enhance evaporative rates and for
dust control. To minimize the net water gain, solutions are recycled from the active tailings cells
to the maximum extent possible. Solutions from Cells l~ and 4A; are brought back to the CCD
circuit where metallurgical benefit can be realized. Cell4B will be operated in the same manner
as CeIl4A. Recycle to other pal1s of the mill circuit are not feasible due to the acid content oflhe
solution.
2.3 Monitoring Programs
Operational monitoring is defined as those monitoring activities that take place only during
operations. This is contrasted with environmental monitoring, which is performed whether or not
the mil l is in operation.
2.3.1 O~eFetieHBI Monitoring and Reporting Under the Mill's GWDP
JJ:.J.l 9!C!../!!J!!lVate~ ¥o~';lorj"{ __________________________________________ ~ _ ~.( Formatted: Font: Italic
aJ Plugged and Excluded Wells
I 11~lbit:lU\WMMt:I'I.""Ml:C Ill! 1t1'1\M0,4999-'-c ~IO
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White Mesa Mill Reclamation Plan
Wells MW-6. MW-7. and MW-8 were plugged because they were in the area of Cell 3 as was
MW-13 in the Ce1l4A area. Wells MW-9 and MW-IO are dry and have been excluded from the
monitoring program. MW-16 is dry and has been plugged as part of the tailings Cell 48
construction.
b) Groundwater Monitoring at the Mill Prior to Issuance of the GWDP
At the time of renewal of the License by NRC in March 1997 and up until issuance of the GWDP
in March 2005. the Mill implemented a groundwater detection monitoring program to ensure
comnliance to 10 CFR Part 40 Appendix A. in accordance with the provisions of the License.
The detection monitoring program was in accordance with the report entitled. Poillfs of
Compliance. White Mesa Uranillm Mill. prepared by Titan Environmental Corporation submitted
by letter to the NRC dated October 5. 1994 (Titan. 1994bl. Under that program. the Mill sampled
monitoring wells MW-5 MW-11. MW-12. MW-14 MW-15 and MW-17. on a quarterly basis.
Samples were analyzed for chloride. potassium. nickel and uranium. and the results of such
sampling were included in the Mill's Semi-Annual Effluent Monitoring Reports that were filed
with the NRC up until August 2004 and with the ORC subsequent thereto.
Between 1979 and 1997 the Mill monitored up to 20 constituents in up to 13 wells. That program
was changed to the Points of Compliance Program in 1997 because NRC had concluded that:
• The Mill and tailings system had produced no imoacts to the perched zone or deep
aquifer: and
• The most dependable indicators of water quality and potential cell failure were
considered to be chloride. nickel. potassium and natural uranium.
c) Issuance of the GWDP
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ffitem8tienel Uf6Hil:lmDenison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
On March 8. 2005. the Executive Secretary issued the GWDP which includes a groundwater
monitoring program that supersedes and replaces the groundwater monitoring requirements set out
in the License. Groundwater monitoring under the GWDP commenced in March 2005. the
results of which are included in the Mill's Quarterly Groundwater MOlJitorhlg Reports that are
filed with the Executive Secretary.
d) Current Ground Water Monitoring Program at the Mill Under the GWDP
The current groundwater monitoring program at the Mill under the GWDP consists of monitoring
at 22 point of compliance monitoring wells: MW-l MW-2 MW-3. MW-3A. MW-S. MW-II.
MW-12 MW-14. MW-15 MW-17 MW-18 MW-19. MW-23. MW-24. MW-25. MW-26
MW-27. MW-28. MW-29. MW-30. MW-31 and MW-32. The locations of these wells are
indicated on Figure 1.5-2.
Part I.E.I.(e) of the GWDP requires that each point of compliance well must he sampled for the
following constituents:
Table 2.3-1
Groundwater Monitoring Constituents Listed in Table 2 of the GWDP
Nutrients:
Ammonia (as N)
Nitrate & Nitrite (as N)
Heavy Metals:
Arsenic
Bervllium
Cadmium
Chromium
Cobalt
Copper
lr2n
Lead
Manganese
Mercury
Molybdenum
Nickel
Selenium
Silver
Thallium
Tin
Uranium
Vanadium
Zinc
Radiologies:
Gross Aloha
Volatile Organic Compounds:
Acetone
Benzene
2-Butanone (MEKl
Carbon Tetrachloride
Chloroform
Chloromethane
Dichloromethane
Naphthalene
Tetrahydrofuran
Toluene
Xylenes <total)
Others:
Field pH (S. U.l
Fluoride
Chloride
Sulfate
TOS
Page 2-12
Revision ~3.2
ffltemetieRsl Uf8fliumDenison Mines (USA) Coq).
White Mesa Mill Reclamation Plan
Further. Part I.E.l.le) of the GWDP, requires that. in addition to pH. the following field parameters
must also be monitored:
• Depth to groundwater
• Temperature
• Tubidityr
• Specific conductance
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!fttemati<m.1 UF.Ri.",Denison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
and that. in addition to chloride and sulfate the following general organics must also be monitored:
• Carbonate bicarbonate sodium. potassium magnesium calcium and total anions and
cations.
Sample frequency depends on the speed of ground water flow in the vicinity of each welL Parts
I.E. Ha) and (b) of the GWDP provide that quarterly monitoring is required for all wells where
local groundwater average linear velocity has been found by the Executive Secretary to he equal to
or greater than 10 feet/year. and semi-annual monitoring is required where the local groundwater
average linear velocity has been found by the Executive Secretary to be less than 10 feet/year.
Based on these cri teria quarterly monitoring is required at MW-II MW-14 MW-25. MW-26.
MW-30 and MW-31 and semi-annual monitoring is required at MW-l. MW-2. MW-3. MW-3A.
MW-5. MW-12. MW-1 5. MW-17. MW-18. MW-19. MW-23. MW-24. MW-27. MW-28 MW-29
and MW-32.
2.3. J.2B!ep Aq,llifp:. _________________________________________________ ~_ ... ~: ~F;.;o,-'m=att,-ed=';.;Fon=t,-lt;;.al.;.< ______ -<
The culinary well (one of the supply wells) is completed in the Navajo aquifer. at a denth of
approximately 1.800 feet below the ground surface. Due to the fact that the deep confined aquifer
Formatted: Outline numbered + level; 4 +
Numbering Style: 1, 2,3, . __ + Start at: 2 +
Alignment: left + Aligned at: 0" + Indent at
OS, Tab stops: Not at OS
Page 2-14
Revision 2;-03.2.
iniema{-ionl~l-thaniumr~gni~.Q!Lt~:Upes (USA) Corp.
White Mesa Mil! Reclamation Plan
§jJllc;~0JQj.s...bxd@EJj~n.JJ.Y ___ l:;Ql~j1gL1J:QnLtbg .. ~Jllilh!5y..12gD;:ll~d 3qnli~I" .. m-UnQlJjl.m:illK._illjh~_~L~J~p
!lq!)jj9Li.!ix~mliIQ~lJJlld.GLJb~L (J \Yl)J~., ..
Page2·lS
Revision ~3.2
iHtemetien.w...m.mDenison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
2.3. J .3 Jeeps anct SWill(!§ ______________________________________________ :_'",: .r:';:.o:.;,m;;.:;tt:;;ed::::',;.':;on;:,;.;' 1::1.;;;t<::... ______ ~
Formatted: Outline numbered + level: <\ +
Numbering Style: 1, 2, 3, ... + Start at: 3 +
Pursuant to Part I.H.8 of the GWDP. Denison has a Sampling Plall for Seeps and Springs ill the
Vicinity ofthe White Mesa Ural/illm Mill Revision: 0 March 17 2009 (the "SSSP") that requires
the Mill to perform groundwater sampling and analysis of all seeps and springs found
down gradient or lateral gradient from the tailings cells.
Under the SSSP seeps and springs sampling is conducted on an annual basis between May 1 and
July 15 of each year to the extent sufficient water is available for sampling. at five identified seeps
and springs near the Mill. The sampling locations were selected to correspond with those seeps
and springs sampled for the initial Mill site characterization performed in the 1978 ER. plus
additional sites located by Denison the BLM and Ute Mountain Ute Indian Tribe representatives.
Samples are analyzed for all ground water monitoring parameters found in Table 2.3-1 above.
The laboratory procedures ut ilized to conduct the analyses of the sampled parameters are those
utilized for groundwater sampling. In addition to these laboratory parameters. the pH.
temperature and conductivity of each sample will be measured and recorded in the field.
Laboratories selected by Denison to perform analyses of seeps and springs samples will be
required to be certified by the State of Utah in accordance with UAC R317-6-6.12.A.
The seeps and springs sampling events will be subject to the Mill's OAP. unless otherwise
specifically modified by the SSSP to meet the specific needs of this type of sampling.
Alignment: left + Aligned at: 0" + Indent at:
0.5", Tab stops: Not at 0.5"
Page 2-16
Revision 2-:03.2
_lienBllIFB.i.mDenison Mines (USA) Corp.
White Mesa Mill Reclamat ion Plan
2.3.1.4 B!SE~a...r:g~ }1i!1!'1Ji!lItioIJ_ !i!c}'!I(.!!ogy an!! _I!'!..~~ _A\'a{la~le _ 'f.e.f~/!o!l!.&'v Standards 1I!'!!:.:--:. ~
Monitoring
2.3.1.4.1 General .---
Part 1.0. of the GWDP sets out a number of Discharge Minimization Technology ('''OMT'') and
Best Available Technology ("SA T"l standards that must be fo llowed, Part I.E, of the GWDP sets
out the Ground Water Compliance and Technology Performance Monitoring requirements. to
ensure that the DMT and BAT standards are met. These provisions of the GWDP, along with the
White Mesa Mill Tailings Management System and Discharge Minimization fDMT) Monitoring
Plan. 9/08 Revision: Denison-6 (the "OMT Plan") the Cell4A BAT Monitoring, Operatiolls lIlId
Maintenance Plan and other plans and programs developed pursuant to such Parts of the GWOP
set out the methods and procedures for inspections of the facility operations and for detecting
fai lure of the system.
In addition to the programs discussed above. the following additional DMT and BAT performance
standards and associated monitoring are required under Parts 1.0 and I.E. of the GWOP
bl Tailings Cell Operation
Part I D.2 of the GWOP provides that authorized operation and maximum disposal capacity in
each of the existing tailings Cell s. 1. 2 and 3 shall not exceed the levels authorized by the 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') Part I.E.7(a) of the GWDP requires that the
wastewater pool elevations in Cell s I and 3 must be monitored weekly to ensure compliance with
the maximum wastewater elevation criteria mandated by Condition 10.3 of the License.
Formatted: Font: Italic
Formatted: Outline numbered + Level: 4 +
Numbering Style: 1,2,3, ... + Start at: 4 +
Alignment: Left + Aligned at: 0" + Indent at:
OS, Tab stops: Not at 0.5"
Formatted: Outline numbered + Level: 5 +
Numbering Style: 1, 2, 3, ...• Start at: 1 +
Alignment: Left + Aligned at: 0" + Indent at:
0.7S~
rage 2-17
Revision 2-:-G3.2
Ifttem8tieflsl Ur8RiumDenison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
Part 1.0.2 further provides that any modifications by Denison to any approved engineering design
parameter at these existing tailings cells requires prior Executive Secretary approval. modification
of the GWDP and issuance of a construction permit.
c) Slimes Drain Monitoring
Part I.D.3(b)(1) of the GWDP requires that Denison must at all times maintain the average
wastewater head in the slimes drain access pipe to be as low as reasonably achievable (ALARAl in
each tailings disposal cell. in accordance with the aporoved DMT Plan. Compliance will he
achieved when the average annual wastewater recovery elevation in the slimes drain access oipe.
determined pursuant to the currently approved DMT Plan meets the conditions in Equation
specified in rart i.D.3(bll1l o[the GWDP.
Part I.E.7(b) of the GWDP requires that Denison must monitor and record monthly the depth to
wastewater in the slimes drain access pipes as described in the currently approved DMT Plan at
Cell 2. and upon commencement of de-watering activities. at Cell 3. in order to ensure compliance
with rart l.D.3(bll1l o[the GWDr.
d) Maximum Tailings Waste Solids Elevation
Part LD.3(c) of the GWDP requires that upon closure of any tailings cell Denison must ensure that
the maximum elevation of the tailings waste solids does not exceed the top of the FML.
Page 2-18
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While Mesa Mill Reclamat ion Plan
e) Wastewater Elevation in Roberts Pond
Part I.D.3(e) of the GWDP requires that Roberts Pond be operated so as to nrovide a minimum
2~foot freeboard at all times. and that under no circumstances will the water level in the pond
exceed an elevation of 5,624 feet above mean sea leveL Part 1.0.3(e) also provides that in the
event the wastewater elevation exceeds this maximum level Denison must remove the excess
wastewater and place it into containment in Cell 1 within 72 hours of discovery.
Part I.E.7(c) of the GWDP requires that the wastewater level in Roberts Pond must be monitored
and recorded weekly. in accordance with the currently approved DMT Plan to determine
compliance with the DMT operations standard in Part I.D.3(e) of the GWOp·
o Inspection of Feedstock Storage Area
Part 1.0.3(0 of the GWDP requires that open-air or bulk storage of all feedstock materials at the
Mill facility awaiting Mill processing must be limited to the eastern portion of the Mill site (the
"ore pad") described by the coordinates set out in that Part of the GWOP and that storage of
feedstock materials at the facility outside of this defined area. must meet the requirements of Part
1.0.11 of the GWOP. Part 1.0. t 1 requires that Denison must store and manage feedstock
materials outside the defined ore storage pad in accordance with the following minimum
performance requirements:
(j) Feedstock materials will be stored at all times in water-tight containers. and
(ii) Aisle ways will be provided at all times to allow visual inspection of each and every
feedstock container. or
Page 2·19
Revision Wll
Ifltematiefl81 Uf8flittmDenison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
(iii) Each and every feedstock container will he placed inside a water-tight overpack
prior to storage. or
(iv) Feedstock containers shall be stored on a hardened surface to prevent spillage onto
subsurface soils. and that conforms with the following minimum physical
requirements:
A. A storage area composed of a hardened engineered surface of asphalt or
concrete. and
8. A storage area designed. constructed. and operated in accordance with
engineering plans and specifications approved in advance by the Executive
Secretary. All such engineering plans or specifications submitted shall
demonstrate compliance with Part I.D.4 of the GWDP and
C. A storage area that provides containment berms to control storm water run-on
and run-off. and
D. Stormwater drainage works approved in advance by the Executive Secretary. or
(v) Other storage facilities and means approved in advance by the Executive Secretary.
Part I.E.7(d) of the GWDP requires that Denison conduct weekly inspections of all feedstock
storage areas to:
(j) Confirm that the bulk feedstock materials are maintained within the approved
feedstock storage area specified by Part I.D.3(O of the GWDP; and
Oi) Verify that all alternate feedstock materials located outside the approved feedstock
storage area are stored in accordance with the requirements found in Part I.D.l l
of the GWDP.
Part I. E. 7(0 further provides that Denison must conduct weekly inspections to verify that each
feed material container complies with the requirements of Part J.D.}1 of the GWDP.
Page 2-20
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Inteffl8tieflsl Uf8ftiumDenison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
The Mill's Standard Operating Procedure under the License for inspection of.he MiJrs ore pad is
contained in Section 3.3 of the DMT Plan.
g) Monitor and Maintain Inventory of Chemicals
Part 1.0.3(g) of the GWDP requires that for all chemical reagents stored at existing storage
facilities and held for use in the milling process Denison must provide secondary containment to
capture and contain all volumes of reagent(s) that might be released at any individual storage area.
Response to spiJIs cleanup thereof. and required reporting must comply with the provisions of the
Mill's Emergellcy Response Plan. which is found in the Mi1l's Storm water Best Management
Practices Plan Revision 1.3: June 12. 2008 (a copy of which is included as Appendix Cl. as
stipulated by Parts I.D.lO and I.H.16 of the GWDP. Part 1.0.3(g) further provides that for any
new construction of reagent storage facilities. such secondary containment and control must
prevent anv contact of the spilled or otherwise released reagent or product with the ground surface.
Part I.E.9 of.he GWDP requires that Denison must monitor and maintain a current inventory of all
chemicals used at the facility at rates equal to or greater than 100 kg/yr. This inventory must be
maintained on~site. and must include:
(iii) Identification of chemicals used in the milling process and the on-site laboratory;
and
(iv) Determination of volume and mass of each raw chemical currently held in storage
at the facility.
2.3.1.5lJ.AT Pp-(OI!,!a!u;e Standards (p! Ce(14A ... -..... -------------------------------~
Formatted: Font: Italic
Formatted: Outline numbered + level: 4 +
Numbering Style: I, 2, 3, ... + Start at: 5 +
Alignment: left + Aligned at: O~ + Indent at:
0.5", Tab stops: Not at 0.5"
Page 2·21
Revision ~3.2
Ifltemotieftsi UrBfliumDenison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
a) BAT Operations and Maintenance Plan
Part 1.0.6 of the GWDP provides that Denison must operate and maintain Cell4A so as to prevent
release of wastewater to groundwater and the environment in accordance with the Mill's Cell4A
BAT Monitoring, Operatiolls and Maintenance PIa". pursuant to Part I.H.19 of the GWDP. The
Mill's Cell4A BAT Monitoring. Operatiolls aJl(1 Maintenance Plal/. 09/08 Revision: Denison 1.3
includes the following performance standards:
(i) The fluid head in the leak detection system shall not exceed I foot above the lowest
point in the lower membrane liner'
(ii) The leak detection system maximum allowable daily leak rate shall not exceed
24.160 galions/day;
(iii) After Denison initiates pumping conditions in the slimes drain layer in Cell 4A.
Denison will provide continuous declining fluid heads in the slimes drain layer. in a
manner equivalent to the requirements found in Part I.D.3(bl for Cells 2 and 3: and
(iv) Under no circumstances shall the freeboard be less than 3-feet in Cell 4A. as
measured from the top of the FM L.
b) Implementation of Monitoring Requirements Under the BAT Operations and
Maintenance Plan
The Cell 4A BAT Monitoring Operations alld Maintenance Plan also requires Denison to perform
the following monitoring and recordkeeping requirements. Similar monitoring and
recordkeeping requirements will be included with the Ce1l4B BAT Plan:
(il Weekly Leak Detection System (LOS) Monitoring -including:
Page 2·22
Revision 2-:G3.2
ffitet=nfttieAB) UfBfliumDenison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
A. Denison must provide continuous operation of the leak detection system
pumping and monitoring equipment. including. but not limited to the
submersible pump. pump controller head monitoring. and flow meter
equipment approved by the Executive Secretary. Failure of any pumping or
monitoring equipment not repaired and made fully operational within 24-hours
of discovery shall constitute failure of BAT and a violation of the GWDP;
B. Denison must measure the fluid head above the lowest point on the secondary
FML by the use of procedures and equipment approved by the Executive
Secretary. Under no circumstance shall fluid head in the leak detection system
sump exceed a J -foot level above the lowest point in the lower FM L on the cell
floor. For pumoses of compliance monitoring this I-foot distance shall equate
to 2.28 feet above the leak detection system transducer:
C. Denison must measure the volume of all fluids pumped from the leak detection
system. Under no circumstances shall the average daily leak detection system
flow volume exceed 24.160 gallons/day' and
D. Denison must operate and maintain wastewater levels to provide a 3-foot
Minimum of vertical freeboard in tailings Cell 4A. Such measurements must
be made to the nearest 0.1 foot.
r age 2-23
Revision ~3.2
IfttemfttieRsl UFE:tftittmOenison Mines (USA) Coq).
White Mesa Mill Reclamation Plan
Iii) Slimes Drain Recovery Head Monitoring
Immediately after the Mill initiates pumping conditions in the Cell 4A slimes drain system
monthly recovery head tests and fluid level measurements will be made in accordance with the
requirements of Parts 1.0.3 and I.E.7(b) of the GWOP and any plan approved by the Executive
Secretary.
2.3. 1.6 ~to'.:.''.!''Yat~r Malla'{e~"pl~ f!..m/ Spill COI!t'.:.O/ Regllirel1!el1ls _____________________ :;'"': .~F;;o';.;m;:;.:;tt;:;ed::;.'.:.FOO:::;;;"..:I;:I.::;I<:.... ______ ~
Formatted: Outline numbered + level: 4 +
Numbering Style: I, 2, 3, ... + Start at: 6 +
Part 1.0.10 of the awop requires that Denison will manage all contact and non-contact
storm water and control contaminant spills at the facility in accordance with the Mill's stormwater
best management practices plan. The Mill's Stomnvater Best Management Practices Plan.
Revision 1.3: June 12.2008 (a copy of which is included as Appendix C) includes the following
provisions:
a) Protect groundwater quality or other waters of the state by design. construction. and/or
active operational measures that meet the requirements of the Ground Water Quality
rrotection Regulations found in UAC R317-6-6.31G) and R317-6-6AIC);
b) Prevent control and contain spills of stored reagents or other chemicals at the Mill site:
c) Cleanup spills of stored reagents or other chemicals at the Mill site immediately upon
discovery: and
d) Report reagent spills or other releases at the Mill site to the Executive Secretary in
accordance with UAC 19-5-114.
Alignment: left + Aligned at: 0" + Indent at:
0.5", Tab stops: Not at OS
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2.3. I. 7 Tai{i'.,!t::,s_ all!'-Sji~l~e~ Drf!J~1 S!!,.!.'{!.li,~r:.. __________________________________ ~', ~ Formatted: Font: ItaliC
Part I.E.S of the GWDP requires that. on an annual basis. Denison must collect wastewater quality
samples from each wastewater source at each tailings cell at the facility including surface
impounded wastewaters and slimes drain wastewaters pursuant to the Mill's Tailings alld Slimes
Drain Sampling Program. Revision O. November 20. 2008 (the "WOSP"). All such sampling
must be conducted in August of each calendar year.
The purpose of the WOSP is to characterize the source term quality of all tailings cell wastewaters.
including impounded wastewaters or process waters in the tailings cells and wastewater or
leachates collected by internal slimes drains. The wasp requires:
• Collection of samples from the pond area of each active cell and the slimes drain of each
cell that has commenced de-watering activities'
• Samples of tailings and slimes drain material will be analyzed at an offsite contract
laboratory and subjected to the analytical parameters included in Table 2 of the GWDP
(see Table 2.3-1 above) and general inorganics li sted in Part I.E.l(d}(2}(ii} of the GWDP,
as well as semi-volatile organic compounds;
• A detailed description of all sampling methods and sample preservation techniques to be
employed'
• The procedures utilized to conduct these analyses will be standard analytical methods
utilized for groundwater sampling and as shown in Section 8.2 of the Mill's OAP;
• The contracted laboratory will be certified by the State of Utah in accordance with UAC
R317-6-6.12A' and
• 30-day advance notice of each annual sampling event must be given. to allow the
Executive Secretary to collect split samples of all tailings cell wastewater sources.
Formatted: Outline numbered + level: 4 +
Numbering Style: 1, 2, 3, ... + Start at: 7 +
Alignment: left + Aligned at: O~ + Indent at:
0.5", Tab stops: Not at 0.5"
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The tailings and slimes drain sampling events are subject to the MiIrs OAP unless otherwise
specifically modified by the wasp to meet the specific needs of this type of sampling.
2.3.2 Monitoring and Inspections Required Under the License
2.3.2.1 §mj ro!'menfa/ Monill!.r!.ng _________________________________________ ~_'-,_
The environmental monitoring program is designed to assess the effecI of Mill process and
disposal operations on the unrestricted environment. Delineation of specific equipment and
nrocedures is presented in the Mill 's Environmental Protection Manllal. included as Appendix A
to the 2007 License Renewal Application.
c) Ambient Air Monitoring
(j) Ambient Particulate
Airborne radionuclide particulate sampling is performed at five locations. termed BHV-I BHV-2.
BHV-4. BHV-5 and SHV-6. With the approval of the NRC and effective November. 1995.
BHV-3 was removed from the active air particulate monitoring program. At that time. the Mill
proposed (and NRC determined) that a sufficient air monitoring data base had been compiled at
station BHV-3 to establish a representative airborne particulate radionuclide background for the
Mill. BHV-6 was installed by the Mill at the request of the White Mesa Ute Community. This
station began operation in July of 1999 and provides airborne particulate information in the
southerly direction between the Mill and the White Mesa Ute Community. Figure 2.3-1 shows
the locations of these air particulate monitoring stations.
Fornlatted: Outline numbered + Level: 3 +
Numbering Style: 1,2, ), ... + Start at: 2 +
Alignment: left + Aligned at: o~ + Indent at: as, Tab stops: Not at as
Formatted: font: Italic
Formatted: Outline numbered + Level: 4 +
Numbering Style: 1, 2, 3, ... + Start at: 1 +
Alignment: left + Aligned at: 0" + Indent at: as, Tab stops: Not at as
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While Mesa Mill Reclamalion Plan
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The present sampling system consists of high volume particulate samplers utilizing mass flow
controllers to maintain an air flow rate of approximately 32 standard cubic feet per minute.
Samplers are operated continuously with a goal for on-stream operating period at ninety percent.
Filter rotation is weekly with quarterly site compositing for particulate radionuc1ide analysis.
Analysis is done for U-natura!. Th-230_ Ra-226_ and Pb-21 0_
See Section 3.13.1.7(8) of the 2007 ER for a summary of historic monitoring results for airborne
particulate.
(ij) Ambient Radon
With the approval of the NRC. Radon-222 monitoring at the SHY stations was discontinued in
1995. due to the unreliability of monitoring equipment available at that time to detect the new 10
CFR standard of 0.1 pCil1. From that time until the present the Mill demonstrated compliance
with the requirements ofR313-15-301 by calculation authorized by the NRC in September 1995
and as contemplated by R3J3-IS-302 (2) (a).
This calculation was performed by use of the MILDOS code for estimating environmental
radiation doses for uranium recovery operations (Strenge and Bender 1981) in 1991 in support of
the Mill's 1997 license renewal and more recently in 2007 in support of the 2007 License Renewal
Application by use of the updated MILDOS AREA code (Argonne 1998), The analysis under
both the MILDOS and MILDOS AREA codes assumed the Mill to be processing high grade
Arizona Strip ores at full capacity. and calculated the concentrations of radioactive dust and radon
at individual receptor locations around the Mill. Specifically. the modeling under these codes
assumed the following conditions:
• 730 000 tons of ore per year
• Average grade of 0.53% U10S
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White Mesa Mill Reclamation Plan
Yellowcake production of 4.380 tons of U}OS per year (8.8 million pounds U}O& per year).
Based on these conditions. the MILDOS and MILDOS AREA codes calculated the combined total
effective dose equivalent from both air particulate and radon at the current nearest residence
(approximately 1.2 miles north of the Mill) i.e. the individual member of the public likely to
receive the highest dose from Mill operations. as well as at all other receptor locations. to be below
the ALARA goal of to mTern/yr for air particulate alone as set out in R313·15·IOH41. Mill
operations are constantly monitored to ensure that operating conditions do not exceed the
conditions assumed in the above calculations. If conditions are within those assumed above.
radon has been calculated to be within regulatory limits. If conditions exceed those assumed
above. then further evaluation will be performed in order to ensure that doses to the public
continue to be within regulatory limits. Mill operations to date have never exceeded the License
conditions assumed above.
In order to determine if detection equipment has improved since 1995. the Mill has. commencing
with the first quarter of2007. re-instituted direct measurements of radon at the five air particulate
monitoring locations currently utilized for air particulate sampling. The reliability of this data is
currently under review by Denison.
d) External Radiation
TLD badges as supplied by Landauer. Inc .. or equivalent are utilized at BHV-1. BHV-2. BHV-3.
BHV-4. BHV-5 and BHV-6 to determine ambient external gamma exposures (see Figure 2.3-1).
System quality assurances are determined by placing a duplicate monitor at one site continuously.
Exchanges of TLD badges are on a quarterly basis. Badges consist of a minimum of five TLD
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chips. Measurements obtained from location BHV-3 have been designated as background due to
BHV-3 's remoteness from the Mill site (SHY-3 is located approximately 3.5 miles west of the
Mill site). For further procedural information see Section 4.3 of the Mill's Ellvirollmemal
Protection Mmwal. included as Appendix A to the 2007 License Renewal Application. See
Section 3.13.1.7(c) of the 2007 ER for a summary of historic monitoring results for external
radiation.
e) Soil and Vegetation
(i) Soil Monitoring
Soil samples from the top one centimeter of surface soils are collected annually at each ofBHV-l.
BHV-2 SHY-3 BHV-4 and BHV-5 (see Figure 2.3·1). A minimum of two kilograms of soil is
collected per site and analyzed for U-natural and Ra-226. For further procedural information see
Section 4.1 of the Mill's Ellvirollmelltal Protection Manllal included as Appendix A to the 2007
License Renewal Application. See Section 3.13.1.7.1 of the 2007 ER for a summary of the
historic results for soil monitoring. The 2007 ER concludes that the results of sampling are low.
less than the unrestricted release limits.
(j) Vegetation Monitoring
Forage vegetation samples are collected three times per year from animal grazing locations to the
northeast (near SHV-I (the meteorological station)). northwest (to the immediate west of the site)
and southwest (by BHV-41 of the Mill site. Samples are obtained during the grazing season. in
the late fall. earl y spring. and in late spring. A minimum of three kilograms of vegetation are
submitted from each site for analysis of Ra ·226 and Pb-2 10. For further procedure information
see Section 4.2 of the Mill's Environmental Protection Manual included as Appendix A to the
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2007 License Renewal Application. See Section 3.13. 7(d) of the 2007 ER for a summary of the
historic results for vegetation monitoring. The 2007 ER concludes that the most recent results
indicate no increase in uptake of Ra-226 and Pb-21 0 in vegetation.
d) Meteorological
Meteorological monitoring is done at a site near BHY -1. The sensor and recording equipment are
capable of monitoring wind velocity and direction. from which the stabi lity classification is
calculated. Data integration duration is one-hour with hourly recording of mean speed. mean
wind direction. and mean wind stability (as degrees sigma theta>.
The data from the meteorological station is retrieved monthly by down loading onto a Campbell
Scientific data module or the equivalent. The data module is sent to an independent
meteorological contractor where the module is downloaded to a computer record and the data is
correlated and presented in a Semi-Annual Meteorological Report.
Monitoring for precipitation consists of a daily log of precipitation using a standard NOAA rain
gauge. or the equivalent. installed near the administrative office. consistent with NOAA
specifications.
Windrose data is summarized in a format compatible with MILDOS and UDAD specifications for
40 CFR 190 comnliance. For further procedural information see Section 1.3 of the MiIrs
Ellvironmental Protection Mal/Jlal included as Appendix A to the 2007 License Renewal
Application. A windrose for the site is set out in Figure 1.1-1.
e) Point Emissions
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White Mesa Mill Reclamation Plan
Stack emission monitoring from yellowcake facilities follows EPA Method 5 procedures and
occurs on a quarterly basis during operation of the facility. Particulate sampling is analyzed for
Una. on a quarterly basis and for Th-230 Ra-226. and Ph-2ID on a semi-annual basis. Demister
and ore stack emission monitoring follows EPA Method 5 procedure on a semi-annual basis.
during operation of the facility. Particulate samples are analyzed for Unat. Th-230. Ra-226. and
Ph-21D. Monitored data includes scrubber system operation levels. process feed levels.
particulate emission concentrations. isokinetic conditions. and radionuclide emission
concentrations. For further procedure information see Section 1.4 of the Mill's Euvirollmelllal
Protection Manual included as Appendix A to the 2007 License Renewal Anplication. Historic
stack emission data are summarized in Section 3.13.1.7(e) of the 2007 ER.
o Surface Water Monitoring
Surface water monitoring is conducted at two locations adjacent to the Mill facility known as
Westwater Canyon and Cottonwood Creek. Samples are obtained annually from Westwater and
quarterly from Cottonwood using grab sampling. For Westwater Creek, samples will be of
sediments if a water sample is not available. Field monitored parameters and laboratory
monitored parameters are listed in Table 2.3-2. For further procedural information see Section
2.1 of the Mill's Environmental Protection Manllal included as Appendix A to the 2007 License
Renewal Application. See Section 3.7.4 of the 2007 ER for a summary of.he historic results for
surface water monitoring.
I
I
I
I
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Table 2.3-2
Operational Phase Surface Water Monitoring Program
Monitoring Sites
Westwater Creek and Cottonwood Creek
Field Requirements
l. temperature C;
2. SQecific Conductivity umhos at 25 C;
3. UH at 25 C;
4. Saml1ie date;
5. Sample ID Code·
Vendor Laborator:y: Reguirements
Semiannual* ( uarterlv
One gallon Unfiltered and Raw One gallon Unfiltered and Raw
One gall on Unfiltered Raw and ureserved to One gallon Unfiltered Raw and Preserved to
oH <2 with HNO, I oH <2 with HNO,
Total Dissolved Solids Total Dissolved Solids
Total Susoended Solids Total Susoended Solids
Gross Alnha
Susncnded Unal
Dissolved Unal
Susnended Ra-226
Dissolved Ra-226
Susoended Th-230
Dissolved Th-230
·ScmjannuaJ sample must be taken a minimym oCCaur months apart
•• Annyal W~lWi!!er ~r!<~k S;iIDJpl\O is anal~~d fQT s~lJli-annual v:aramel~ni.
RadiQnuQlid~S; and LLDs; B::12Qrtcd in 11(;:i/ml
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White Mesa Mill Reclamation Plan
2.3.2.2 iJfjditif!./~a! MO!I{tC!t:..i'!.g, and 1!,~'?:e~tjOl~'i Regllire(~ l!'!.1.er!he Li~e!,!'!. ______________ :':-0::. : ~F;;.,,,m,,.::tt;;""::;.' ~FOO:;;;;"..:It::.;;;I<:..,-_.,..._.,... __ ~
Formatted: Outline numbered + level: 4 +
Numbering StYle: 1, 2, 3, ... + Start at: 2 +
Under the License daily. weekly and monthly inspection reporting and monitoring are required by
NRC Regulatory Guide 8.31. Information Relevant to Ensuring that Occupational Radiation
Exposures at Uranium RecovelY Facilities will he As Low As is Reasonable Achievable. Revision
I. May 2002 ("Reg Guide 8.31"'). by Section 2.3 of the Mill's ALARA Program and by the DMT
Plan. over and above the inspections described above that are required under the aWDP. A copy
of the Mill's ALARA Program is included as Appendix I to the 2007 License Renewal
Application.
a) Daily Inspections
Three types of daily inspections are performed at the Mill under the License:
(il Radiation Stafflnspections
Paragraph 2.3.1 of Re •. Guide 8.31 provides that the Mill's Radiation Safety Officer C'RSO'·) or
designated health physics technician should conduct a daily walk-through (visual) inspection of all
work and storage areas of the Mill to ensure proper implementation of good radiation safety
procedures including good housekeeping that would minimize unnecessary contamination.
These inspections are required by Section 2.3.1 of the Milrs ALARA Program and are
documented and on file in the Mill's Radiation Protection Office.
(iil Operating Foreman Inspections
30 CFR Section 56.18002 of the Mine Safety and Health Administration regulations requires that a
Alignment: left + Aligned at: 0" + Indent at:
OS, Tab stops: Not at OS
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White Mesa Mill Reclamation Plan
competent person designated by the operator must examine each working place at least once each
shift for conditions wh ich may adversely affect safety or health. These daily inspections are
documented and on file in the Mill's Radiation Protection Office.
(iii) Daily Tailings Inspection
Paragraph 2.2 of the OMT Plan requires that during Mill operation. the Shift Foreman or other
person with the training specified in paragraph 2.4 of the OMT Plan. designated by the RSO. will
perform an inspection of the tailings line and tailings area at least once per shift paying close
attention for potentia l leaks and to the discharges from the pipelines. Observations by the
Inspector are recorded on the appropriate line on the Mill's Daily Inspection Data form.
b) Weekly Inspections
Three tvoes of weekly inspections are performed at the Mill under the License:
(il Weekly Inspection of the Mill Forms
Paragraph 2.3.1 of Reg. Guide 8.3 1 provides that the RSQ and the Mill foreman should. and
Section 2.3.2 of the Mill's ALARA Program provides that the RSO and Mill foreman. or their
respective designees. shall conduct a weekly inspection of all Mill areas to observe general
radiation control practices and review required changes in procedures and equipment. Particular
attention is to be focused on areas where potential exposures to personnel might exist and in areas
of operation or locations where contamination is evident.
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(ij) Weekly Ore Storage Pad Inspection Forms
Paragraph 3.3 of the DMT Plan requires that weekly feedstock storage area inspections will be
performed by the Radiation Safety Department. to confirm that the bulk feedstock materials are
stored and maintained within the defined area of the ore pad and that all alternate feed materials
located outside the defined ore pad area are maintained within water tight containers. The results
of these inspections are recorded on the Mill's Ore Storage/Sample Plant Weekly Inspection
~
(iii) Weekly Tailings and DMT Inspection
Paragraphs 3.1 and 3.2 of the DMT Plan require that weekly inspections of the tailings area and
DMT requirements be performed by the radiation safety department.
c) Monthly Reports
Two types of monthly reports are prepared by Mill stafT:
(il Monthly Radiation Safety Reports
At least monthly. the RSO reviews the results of daily and weekly inspections including a review
of all monitoring and exposure data for the month and provides to the Mill Manager a monthly
report containing a written summary of the month's significant worker protection activities
(Section 2.3.4 of the Mill's ALARA Programl.
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liD Monthly Tailings Inspection Reports
Paragraph 4 of the DMT Plan requires that a Monthly Inspection Data form be completed for the
monthly tailings inspection. This inspection is typically performed in the fourth week of each
month and is in lieu of the weekly tailings inspection for that week.
Mill staff also prepares a monthly summary of all daily. weekly. monthly and quarterly tailings
inspections.
d) Quarterly Tailings Inspections
Paragraph 5 of the DMT Plan requires that the RSO or his designee perform a quarterly tailings
inspection.
e) Annual Evaluations
The following annual evaluations are performed under the License. as set out in Section 6 of the
DMT Plan.
(il Annual Technical Evaluation
An annual technical evaluation of the tailings management system must be performed by a
registered professional engineer (PEl. who has experience and training in the area of geotechnical
aspects of retention structures. The technical evaluation includes an on-site inspection of the
tailings management system and a thorough review of all tailings records for the past year. The
Technical Evaluation also includes a review and summary of the annual movement monitor survey
(see paragraph liil belowl.
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All tailings cells and corresponding dikes are inspected for signs of erosion subsidence shrinkage.
and seepage. The drainage ditches are inspected to evaluate surface water control structures.
In the evenl tailings capacity evaluations were performed for the receipt of alternate feed material
during the year the capacity evaluation forms and associated calculation sheets will be reviewed to
ensure that the maximum tailings capacity estimate is accurate. The amount of tailings added to
the system since the last evaluation will also be calculated to determine the estimated capacity at
the time of the evaluation.
As discussed above. tai lings inspection records consist of daily weekly monthly and quarterly
tailings inspections. These insoection records are evaluated to determine if any freeboard limits
are being approached. Records will also be reviewed to summarize observations of potential
concern. The evaluation also involves discussion with the Environmental and/or Radiation
Technician and the RSO regarding activities around the tailings area for the past year. During the
annual inspection. photographs of the tailin gs area are taken. The training of individuals is also
reviewed as a part of the Annual Technical Evaluation.
The registered engineer obtains copies of selected tailings inspections. along with the monthly and
quarterly summaries of observations of concern and the corrective actions taken. These copies are
then included in the AlIlIlIal Technical Evaluation Report.
The Ammo/ Technical Evaluation Report must be submitted by September 1 $1 of every year to the
Directing Dam Safety Engineer. State of Utah. Natural Resources.
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White Mesa Mill Reclamation Plan
(m Annual Movement Monitor Survey
A movement monitor survey is conducted by a licensed surveyor annually in accordance with
Conditon 11.3 of the License. approvedon June 17.2010. The movement monitor survey consists
of surveying monitors along dikes 3-S 4A-Wand 4A-S to detect any possible settlement or
movement of the dikes. The data generated from this survey is reviewed and incorporated into
the AmllIal Technical Evaluation Report of the tailings management system.
(iii) Annual Leak Detection Fluid Samples
In the event solution has been detected in a leak detection system in Cells I 2 or 3 a sample will he
collected on an annual basis. This sample will be analyzed according to the conditions set forth in
License Condition II.3.e. The results of the analysis will be reviewed to determine the origin of
the solution.
lR-lfte--mH.J--faetHties--flrea, the epet'fttiet'lel-meft-ttofin!'"-I»'egr-ams--eens-is+-eHmuenl-gBs-staek
semJ3liftg; flail) iftspeetisR sf f.1reeess t8ftlEs, lifles afld eflHipmeRt; aFld daily iflspeetisft ef tailiFlg
impeHftflmeftts aRd lealE deteetieR systefns. QHerterl)' en:iHeRt gas steelE semples ere eelleeted
eR all mill "reees!; staehs .,hen these precess s)stems are eJ3eratiRg. These iRelude the
yelle" colEe fir) ers Ne. 1 eRd Ne. 2, the. eRediHm df)er staciE, their respeetive seruBber staeies, the
demister steelE, aRd the grilzl)· steelE.
A , iSHal iRspeetieR is made dail)· by sHper,·isery perseRRel efell preeess taRIEs eRd Eiiseharge !iRes
iR the mill aRd ef the teiliflg5 fflaflageFl'leflt area. 1ft the e. CRt ef a feilHre ifl eRe ef the RerFl'lel
I II IiSl:kS\W.\lR{;I'LIIS\li':CW~ M,'l"1Mty-+999hanc ~IO
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I'reees!I streams, eeFfeeti. e aetieH!! 8re talEen Ie ens life thet there Bre He eiseharges Ie the
LealE deteetien systen~s ("LQS") t:lfteef eeeR tailings eel I 8re menit6ree fer the ~fesenee efsslHtien
weeld). lfsehniefl is fJrescnt in the LOS BrGell!! 2, 3, Bf 4, 8 pregram, eeseri~ee l:uuler Lieel'lse
CeRaitien 11.3. fJrB,t'ides fer Betiens Ie be talEen.
2.3.2 Envir6flfflcFltei Menit6riflg
EfI\ i[aRmenta] ffl6nitBrifig aeAsis!s eftl.e fella o'Iing: gr6l:tnElYl8ter end SHFmee Vi flier samples; eir
paftieHiate samples, tamms ffldietiefl meaSl:lrel11eRts, seil, end Yeget&tien samples. Refer Ie the
Semi-aflffiJs) En:1uent-R-el*ffis-eeBtitifletl 1ft Apf.lenailt A fef s&mf'~mg-lecal-ieFt;--freqHeney-&fle
ftftfttyliea l results.
Gr8tiflB .. flIer
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Wells MW 6, MW 7, BRa M'.V 8 "ere plugged beeause the) ... ere HRder Cell 3, as 'NAS MW 13,
I:IR6er Cell 4A. Wells MW 9 BRd MW H) ere Bf)' OHEI have beeR e'leluseel [rem the meRiteriRg
J3fegFsm. The teft menit6riflg .. ells iFi Bf ReftF the ul"permest 8EjHifer ere MW 1, MW 2, MW 3,
Mv.' 4,MW 5,MW 11,MW 12,1\4',11 14,MW lSftfldMW 17. These ilellsv8fyiRtiepthfrem
94 Ie 189 feet. Fie .. fetes in these ... 'ells VBf) [rem 15 gall ens per maRtA te lQ geileRs per heuf.
The e.liAa,) .. ell (eAe ef Ihe s.~~I) .. ells) i9 ee",~lelea iA Ihe ~Ia .'aje a~.ife" al a ae~Ih ef
apl"f61timatei) 1,8Q(;) feet helew the gt"61:1R8 surraee.
The greuHB'liater meniteriRg I"f6gt"Sffl eet15ists ef parameters meosHfeEl ttHftFteri) sHd
semi-enntta-~ftfterly pSf8meteFS--ffie.luae: )')1-1, speeifie eanaHetflnee,tempemt-tue, depth te
'Hater, ehlerides, sulfates, tetal dissel'red selids (TDS), nieleel, )3etassium, ane U naHUftl. The
I)arameters measl:1ree eR a semi aRRl:1al hasis, iR addition te the fluaFterly )3arameters, are: arseRie,
seleRil:1ll't, sedium, raeium 226, tharium 230, afle lea8 210. Semi aRflual parameters · ... hiett all
measl:1redare: all )3Rysieal ettemieal eriteria sf Etl:1aFterly safl'l:)3ling as ·.vell as aElElitienal eRal)te
~.,alflelers a" Se Na aAa RaaieA.eliaes Ra 22~, Th 239, aHa Pe2le,
SUffaee Water
Surfaee •• ater semples ere tahen frem the 1'./e Heorby streams, West .... eter Creelt afld Cettenweed
Creele. Galtem.eed Creelt usually eentiHftS-fttnRittg-weter;--btu ttas else been flr) en eeeesieft.:
West .... ater (reelt rerel) eeRtBms rUflfliflg .. Bter, Bne 'NneR it dees, it is frem )3reei)3itatiefl rl:1f1eff.
Weter semples Bre eelleeted fluarterly frem Cettan ..... eed (reelt BRe aHBI)'zea far TDS anEi tetal
sl:ls)3efltieti selias (TSS). Additienal semi aRRHa) .. ater sam)3les are eelleetea at a ll'tiftiH'H:Ul't ef
fatlr (4) mefttRs apart. These samples Bre aRal)zea fer TDS, TSS, eissai-.ed ane sl:1s)3ended
U Aal, Ra 22~, aAa Th 239,
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White Mesa Mill Reclamation Plan
GuFFefltly-th~Ffln=t-itleltJees-s8mfl"IiHg-w8ter-fr.em-Westwatef Creelt SAce 6 year, if the ereeie is
fle..,liRg. lIewe,.er. if ,'later is Ret fl:lHRiRg. 8A aiteFf'late sail 5e:ffiJ3le is eolleeted frem the ereek
bea. Water samples from Westwater Cfeel~ ere ftAalYi!:ed fer TDS, TS8, Disseh'ed BAd
Sl::IspefideEi U RBt, Re 226, 8f1d Tn 239. If a sail sample is eolleeted, it is ftR81YleEl fef U fl8t BRe
R. 226 (~er LiefA'f C.A~ili.A 2QC).
Radialia"
Natural raeietiefl meRit6riAg iftelHBeS air 138flieHIete sampling, gamma rodiatian IfleaSt:I:Femeftts,
end .'egela.ian ftRtI sail sampling. Air partieulate ffl6nit6riflg is eenBueteti eefltiHH6HSi) at feur
fl16nit&Aflg-statiens laeeled 8feuRd-t-I~tfflef) of the-mHh----Gemm8-flldiatieft measurements;
• egetatieFl safflj:'ling. and sail saffi~iiFlg are eandHeteaat fl. e laeatiens. See SeetieA 1.8 fer details
eeneeFfling the maFliteriflg pregraffl.
Gamma radiatieFl Ie. els ere aetermined at the H. e eft. ireftmefttal menitering staliens aAd aFe
repeFted Etuarteriy. witA dUj:'lieste samples eelleeted al the nearest residenee.
ApJ3reJlimateiy Ave peHnds ef "He" gre\"h" .'egetatisn samples are eelleeted £rem areas
"nef'theast af the mill. naAhwest af the mill. ana ssutA ..... est af the mill" dHriHg eafly spfing. late
spriflg, ena late fall. Seffll)ie ealleetisfl areas .Sf) ael)eAding aft tAe gre •• tA year (i.e. iH Ie .. ef He
meistHfe )'e8rs-it-m~eYeftll-eeres-ffl-S.f:Ze te eelleet five peHAas ef • egetatieH, uAile
in "'Net" )'eafs a mHeA sll'laller afea is AeeaeS). '1egetatisn is anal)~ed fer faeiHffl 226 aRd
1e.~ 219.
Seils efe samf3ledet eeah af the Ave en'/ifanmentel manitaring statians annually in AugHSt. TAe
sails ere eHBI)'~ed fer U RBtHfai BREI fediHm 226.
OENISONr)~~
MINES
Denison Mines (USA) Corp.
1010 11th S1ree~ Suite 950
Denver, CO 80261
USA
rei: 303 628·7798
Fax: 303 389~121
www.d.nllonmln ... com
White Mesa Mill Reclamation Plan
Revision 3.2
Section 3
White Mesa Mill and Tailings
Management System
June 2010
State of Utahlle.(2) Byproduct Material License # UT1900479
Denison Mines (USA) Corp.
www.denlsonmln ••. com
1050 17th Street, Suite 950
Denv.r, CO, USA 80265
Tel: 303628·7798
Fax: 303 389~125
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Denison Mines (USA) Corp.
White Mesa Mill Reclamation Plan
3.0 RECLAMATION PLAN
This section provides an overview of the Mill location and property; details the facilities to be
reclaimed; and describes the design criteria applied in this Plan. Reclamation plans and
specifications are presented in Attachment A. Attachment B presents the quality plan for
construction activities. Attachment C presents cost estimates for reclamation. Attachments D
through H present additional material test results and design calculations to support the
reclamation plan.
3.1 Location and Property Description
The White Mesa Mill is located six miles south of Blanding, Utah OIl US Highway 191 on a parcel
of land encompassing all or part of Sections 21, 22, 27, 28, 29, 32, and 33 of T37S, R22E, and
Sections 4, 5, 6, 8, 9, and 16 ofT38S, R22E, Salt Lake Base and Meridian described as follows
(Figure 3.1-1):
The south half of Section 21; the southeast quarter of the southeast quarter of
Section 22; the northwest qUaJier of the northwest quarter and lots 1 and 4 of
Section 27 all that part of the southwest quarter of the northwest quarter and the
northwest quarter southwest quarter of Section 27 lying west of Utah State
Highway 163; the northeast quarter of the northwest quarter, the south half of the
northwest quarter, the northeast quarter and the south half of Section 28; the
southeast quarter of the southeast quarter of Section 29; the east half of Section 32
and all of Section 33, Township 37 South, Range 22 East, Salt Lake Base and
Meridian. Lots 1 through 4, inclusive, the south half of the north half, the
southwest quarter, the west half of the southeast quarter, the west half of the east
half of the southeast quarter and the west half of the east half of the east half of the
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White Mesa Mill Reclamation Plan
southeast quarter of Section 4; Lots I through 4, inclusive, the south half of the
north half and the south half of Section 5 (all); Lots I and 2, the south half of the
northeast quarter and the south half of Section 6 (E 112); the northeast quarter of
Section 8; all of Section 9 and all of Section 16, Township 38 South, Range 22 East,
Salt Lake Base and Meridian. Additonalland is controlled by 46 Mill site claims.
Total land holdings are approximately 5,415 acres ..
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INSERT FIGURE 3. J -J
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3.2 Facilities to be Reclaimed
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White Mesa Mill Reclamation Plan
See Figure 3.2-1 for a general layout of the mill yard and related facilities and the restricted area
boundary.
3.2.1 Summary of Facilities to be Reclaimed
The facilities to be reclaimed include the following:
• Cell 1 (evaporation). Cell 1 was previously referred to as Cell I-I. It is now referred to
as Cell 1;
• Cells 2 and 3, 4A and 4B (tailings);
• Mill buildings and equipment;
• On-site contaminated areas; and
• Off-site contaminated areas (i.e., potential areas affected by windblown tailings).
The reclamation of the above facilities will include the following:
• Placement of contaminated soils, crystals, and synthetic liner material and any
contaminated underlying soils from Cell 1 into tailings Cells 4A or 4B.
• Placement of a compacted clay liner on a portion of the Cell 1 impoundment area to be
used for disposal of contaminated materials and debris from the Mill site
decommissioning. (the Cell 1 Tailings Area)
• Placement of materials and debris from Mill Decommissioning into tailings Cells 4A or 4B
or in the Cell 1 Tailings Area;
• Placement of an engineered multi-layer cover over the entire area of Cells 2, 3, 4A and 4B
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and the Cell 1 Tailings Area.
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e Construction of runoff control and diversion channels as necessary;
• Reconditioning of Mill and ancillary areas; and
• Reclamation of borrow sources.
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INSERT FIGURE 3.2-1
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3.2.2 Tailings and Evaporative Cells
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White Mesa Mill Reclamation Plan
The following subsections describe the cover design and reclamation procedures for Cellsl-I, 2, 3,
4A and 4B. Complete engineering details and text are presented in the Tailings Cover Design
report, Appendix D, previously submitted. Additional infonnation is provided in Attachments D,
E and F to this submittal.
3.2.2.1 Soil Cover Design
A six-foot thick soil cover to be placed over the uranium tailings and mill decommissioning
materials in the Cell I-I Tailings Area, Cell 2, Cell 2, Cell 4A and Cell 4B was designed using
on-site materials that will contain tailings and radon emissions in compliance with regulations of
the NRC, the State of Utah, and by reference, the EPA. The cover consists of a one-foot thick
layer of clay, available from within the site boundaries (Section 16 or stockpiles on site), below
two feet of random fill (frost barrier), available from stockpiles on site. The clay is underlain by
three feet (minimum) random fill soil (platfOlm fill), also available on site. In addition to the soil
cover, a minimum three-inch (on the cover top) to 8-inch (on the cover slopes) layer of riprap
mate11al will be placed over the compacted random fill to stabilize slopes and provide long-tenn
erosion resistance (see Attachments D and H for characterization of cover materials).
Uranium tailings soil cover design requirements for regulatory compliance include:
Attenuate radon flux to an acceptable level (20 picoCuries-per meter squared-per second
[pCihn2/sec]) (NRC, 1989) and 40 CFR 61.250-61.256;
Minimize infiltration into the reclaimed tailings cells;
Maintain a design life of up to 1,000 years or to the extent reasonably achievable, and in
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any case for at least 200 years; and
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White Mesa Mill Reclamation Plan
Provide long-term slope stability and geomorphic durability to withstand erosional forces
of wind, the probable maximum flood event, and a horizontal ground acceleration of 0.1 g
due to seismic events.
Several models/analyses were utilized in simulating the soil cover effectiveness: radon flux
attenuation, hydrologic evaluation of infiltration, freeze/thaw effects, soil cover erosion
protection, and static and pseudo static slope stability analyses. These analyses and results are
discussed in detail in Sections 3.3.1 through 3.3.5, and calculations are also shown in the Tailings
Cover Design report, (Appendix D, Attachment E and Attachment F). The soil cover (from top to
the bottom) will consist of: (I) minimum of three inches of riprap material; (2) two feet of
compacted random fill; (3) one foot of compacted clay; and (4) minimum three feet of compacted
random fill soil.
The final grading plan is presented in Section 5, Figure 5.1-1. As indicated on the figures, the top
slope of the soil cover will be constructed at 0.2 percent and the side slopes, as well as transitional
areas between cells, will be graded to five horizontal to one vertical (5H: 1 V).
A minimum of three feet random fill is located beneath the compacted fill and clay layers (see
cross-sections on Figures 5.1-2 and 5.1-3). The purpose of the fill is to raise the base of the cover
to the desired subgrade elevation. In many areas, the required flll thickness will be much greater.
However, the models and analyses presented in the Tailings Cover Design report (Appendix D)
were performed conservatively, assuming only a three-foot layer. For modeling purposes, this
lower, random fill layer was considered as part of the soil cover for performing the radon flux
attenuation calculation, as it effectively contributes to the reduction of radon emissions (see
Section 3.3.2). The fill was also evaluated in the slope stability analysis (see Section 3.3.6).
However, it is not defined as part of the soil cover for other design calculations (infiltration,
! I :\USERS\ WMR C I'I.N'$EC1'03 Rc\'_~.2 .RJ'TdIIllC ~o I 0
freeze/thaw, and cover erosion).
3.2.2.2 Cell 1-1
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Cell 1, used during mill operations solely for evaporation of process liquids, is the northernmost
existing cell and is located immediately west of the mill. It is also the highest cell in elevation, as
the natural topography slopes to the south. The drainage area above and including the cell is 216
acres. This includes drainage from the Mill site.
Cell I will be evaporated to dryness. The synthetic liner and raffinate crystals will then be
removed and placed in tailings Cells 4A or 4B. Any contaminated soils below the liner will be
removed and also placed in the tailings cells. Based on current regulatory criteria, the current
plan calls for excavation of the residual radioactive materials to be designed to ensure that the
concentration ofradium-226 in land averaged over any area of lOa square meters does not exceed
the background level by more than:
• 5 pCi/g, averaged over the first IS cm of soil below the surface, and
• IS pCi/g, averaged over a 15 cm thick layer of soil more than 15 cm below the surface.
A portion of Cell I (i.e., the Cell I Tailings Area), adjacent to and running parallel to the
downstream cell dike, will be used for permanent disposal of contaminated materials and debris
from the mill site decommissioning and windblown cleanup. The actual area of Cell 1-1 Tailings
Area needed for storage of additional material will depend on the status of Cell 4A and 4B at the
time of final mill decommissioning. A portion of the Mill area decommissioning material may be
placed in Cell 4A or 4B if space is available, but for PU!lloses of the reclamation design the entire
quantity of contaminated materials from the Mill site decommissioning is assumed to be placed in
the Cell I Tailings Area. This results in approximately 10 acres of the Cell 1 Tailings Area and
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being utilized for permanent tailings storage. The remaining area of Cell 1 will then be
breached and converted to a sedimentation basin. All runoff i]-om the Cell 1-1 Tailings Area, the
Mill area and the area immediately north of Cell 1 will be routed into the sedimentation basin and
will discharge onto the natural ground via the channel located at the southwest corner of the basin.
The channel is designed to accommodate the PMF flood.
The HEC-l model was used to determine the PMF and route the flood through the sedimentation
basin (Attachment 0). The peak flow was detennined to be 1,344 cubic feet per second (cfs). A
20-foot wide channel will discharge the f10w to the natural drainage. During the local storm PMF
event, the maximum discharge through the channel will be 1,344 cfs. The entire flood volume
will pass through the discharge channel in approximately four hours.
At peak flow, the velocity in the discharge channel will be 7.45 feet per second (fps). The
maximum flow depth will be 1.45 feet. This will be a bedrock channel and the allowable velocity
for a channel of this type is 8-10 fps, therefore no riprap is required. A free board depth of 0.5 feet
will be maintained for the PMP event.
3.2.2.3 Cell 2
Ce112 will be filled with tailings and covered with a multi-layered engineered cover to a minimum
cover thickness of six feet. The final cover will drain to the south at a 0.2 percent gradient.
The cover will be as described in Section 3.2.2.1 above, and will consist of a minimum of three feet
of random fill (platform fill), followed by a clay radon barrier of one foot in thickness, and two feet
of upper random fill (frost barrier) for protection of the radon barrier. A minimum of three inches
of rock will be utilized as armor against erosion. Side slopes will be graded to a 5:1 slope and will
have 0.67 feet (8 inches) of rock armor protection.
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3.2.2.4 Cell 3
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Cell 3 will be filled with tailings, debris and contaminated soils and covered with the same
multi-layered engineered cover as Cell 2.
3.2.2.5 Cell4A
Cell 4A will be filled with tailings, debris and contaminated soils and covered with the same
multi-layered engineered cover as Cell 2 and Cell 3.
3.2.2.6 Ce1l4B
Cell 4B will be filled with tailings, debris and contaminated soils and covered with the same
multi-layered engineered cover as Cell 2, Cell 3 and Ce1l4B.
3.2.3 Mill Decommissioning
A general layout of the mill area is shown in Figure 3.2.3-1.
3.2.3.1 Mill Building, Equipment, and Other lle.(2) Byproduct Material
The uranium and vanadium sections, including ore reclaim, grinding, pre-leach, leach, CCD, SX,
and precipitation and drying circuits as well as the alternate feed circuit, decontamination pads,
scale house, sample plant, truck shop and all other structures on site will be decommissioned as
follows:
All equipment including instrumentation, process piping, electrical control and switchgear, and
contaminated structures will be removed. Contaminated concrete foundations will be demolished
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and removed or covered with soil as required. Uncontaminated equipment, structures and waste
materials from Mill decommissioning may be disposed of by sale, transferred to other
company-owned facilities, trans felTed to an appropriate off-site solid waste site, or disposed of in
one of the tailings cells. Contaminated equipment, structures and dry waste materials from Mill
decommissioning, contaminated soils underlying the Mill areas, and ancillary contaminated
materials will be disposed of in tailings Cell 4A, Cell 4B, or the Cell I Tailings Area. All other
lle.(2) byproduct material on site will be disposedofin Cell4A or CeIl4B.
Debris and scrap will have a maximum dimension of 20 feet and a maximum volume of 30 cubic
feet. Material exceeding these limits will be reduced to within the acceptable limits by breaking,
cutting or other approved methods. Empty drums, tanks or other objects having a hollow volume
b'Teater than five cubic feet will be reduced in volume by at least 70 percent. If volume reduction
is not feasible, openings shall be made in the object to allow soils or other approved material to
enter the object.
Debris and scrap will be spread across the designated areas to avoid nesting and to reduce the
volume of voids present in the placed mass. Stockpiled soils, and/or other approved material
shall be placed over and into the scrap in sufficient amounts to fill the voids between the large
pieces and the volume within the hollow pieces to form a coherent mass.
See also Section 3.1 of Attachment A.
The estimated reclamation costs for surety are set out in Attachment C. Attachment C will be
reviewed and updated on a yearly basis.
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INSERT FIGURE 3.2.3-1
LAYOUT OF MILL YARD AND ORE PAD
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3.2.3.2 Mill Site
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Contaminated areas on the Mill site will be primarily superficial and includes the ore storage area
and surface contamination of some roads. All ore will have been previously removed from the
ore stockpile area or will be transported and disposed of as contaminated material. All
contaminated materials will be excavated and be disposed in one of the tailings cells. The depth
of excavation will vary depending on the extent of contamination and will be governed by the
criteria in Attachment A, Section 3.2.
Windblown material is defined as Mill-derived contaminants dispersed by wind to surrounding
areas. Windblown contaminated material detected by a gamma survey using the criteria in
Attachment A, Section 3.2, will be excavated and disposed in one of the tailings cells.
Disturbed areas will be covered, !"Taded and vegetated as required. The proposed grading plan for
the Mill site and ancillary areas is shown on Figure A-3.2-1 in Attachment A.
3.3 Design Criteria
As required by Part I.H.I of the GWDP, Denison is in the process of completing an infiltration and
contamination transport model of the final tailings cover system to demonstrate the long-term
ability of the cover to protect nearby groundwater quality. Upon review of such modeling, the
executive Secretary will determine if changes to the cover systems as set outin the iPlan are needed
to ensure compliance with the performance criteria contained in part I.D.8 of the GWDP.
Although the modeling has not been completed, modeling results to date suggest that some
changes to the final cover design as set out in this Plan will be needed. However, as the details of
such re-design have not been finalized at this time, the approved 2000 cover deiagn and basis will
continue to be used for this version of the Plan. This Plan will be amended in the future to
incorporate any changes to the design of the tailings cover system that result from the current
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modeling effort.
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The design criteria summaries in this section are adapted from Tailings Cover Design, Mill (Titan,
1996). A copy of the Tailings Cover Design report is included in Appendix D, previously
submitted. It contains all of the calculations used in design discussed in this section. Additional
design information is included in Attachments D through H to this submittal.
3.3.1 Regulatory Criteria
Information contained in 10 CFR Part 20, Appendix A, 10 CFR Part 40, and Appendix A (0 10
CFR Part 40 (which are incorporated by reference into UAC R313-24-4), and 40 CFR Part 192
was used as criteria in final designs under this Plan. In addition, the following documents also
provided guidance:
• EP A, 1994, The Hydrologic Evaluation of Landfill Performance (HELP) Model, Version
3, EPA/600/R-94/168b, September;
• NRC, 1989, "Regulatory Guide 3.64 (Task WM-503-4) Calculation 0/ Radon Flux
Attenuation by Earthen Uranium Mill Tailings Covers, March;
• NRC, 1980, Final Staff Technical Position Design 0/ Erosion Protection Covers /01'
Stabilization a/Uranium Mill Tailings Sites, August;
• NUREGICR-4620, Nelson, 1. D., Abt, S. R., et. aI., 1986, Methodologies /01' Evaluating
Long-Term Stabilization Designs a/Uranium Mill Tailings Impoundments, June;
• NUREGICR-4651, 1987, Development 0/ Riprap DeSign Criteria by Riprap Testing in
Flumes: Phase 1, May;
• U. S. Department of Energy, 1988, Effect 0/ Freezing and Thawing on UMTRA Covers,
Albuquerque, New Mexico, October; and.
• NUREG 1620,2003, Standard Review Plan/or the review of a reclamation Plan /01' Mill
Tailings Sites Under Title 11 of the uranium Mill Tailings radiation Control Act of 1978.
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As mentioned above, the requirements set out in Part I.D.8 of the GWDP require that the cover
system for each tailings cell will be designed and constructed to meet the following minimum
requirements for a period of not less than 200 years:
• Minimize the infiltration of precipitation or other surface water into the tailings, including,
but not limited to the radon barrier;
• Prevent the accumulation of leachate head within the tailings waste layer that could rise
above or over-top the maximum FML elevation internal to any disposal cell, i.e. create a
"bathtub" effect; and
• Ensure that groundwater quality at the compliance monitoring wells deosn at exceed the
GWQSs or GWCLs specified in Part I.C.l and table 2 of the GWDP.
Upon completion of the Infiltration Analysis, this Plan will be revised as necessary to ensure
compliance with these requirements.
3.3.2 Radon Flux Attenuation
The EPA rules in 40 CFR Part 192 require that a "uranium tailings cover be designed to produce
reasonable assurance that the radon-222 release rate would not exceed 20 pCi/nl/sec for a period
of 1,000 years to the extent reasonably achievable and in any case for at least 200 years when
averaged over the disposal area over at least a one year period" (NRC, 1989). NRC regulations
presented in 10 CFR Part 40 (incorporate by reference into UAC R313-24-4) also restrict radon
flux to less than 20 pCi/m2/sec. The following sections present the analyses and design for a soil
cover which meets this requirement.
3.3.2.1 Predictive Analysis
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The soil cover for thc tailings cells at White Mesa Mill was evaluated for attenuation of radon gas
using the digital computer program, RADON, presented in the NRC's Regulatory Guide 3.64
(Task WM 503-4) entitled Calculation 0/ Radon Flux Attenuation by Earthen Uranium Mill
Tailings Covers. The RADON model calculates radon-222 flux attenuation by multi-layered
earthen uranium mill tailings covers, and determines the minimum cover thickness required to
meet NRC and EPA standards. The RADON model uses the following soil properties in the
calculation process:
• Soi11ayer thickness [centimeters (cm)];
• Soil porosity (percent);
• Density [grams-per-cubic centimeter (gm/cm3)];
• Weight percent moisture (percent);
• Radium activity (piC/g);
• Radon emanation coefficient (unit1ess); and
• Diffusion coefficient [square centimeters-per-second (cm%ec)].
Physical and radiological properties for tailings and random fill were analyzed by Chen and
Associates (1987) and Rogers and Associates (1988). Clay physical data from Section 16 was
analyzed by Advanced Terra Testing (1996) and Rogers and Associates (1996). Additional
testing of cover materials was perfOlmed in April 1999. The test results are included 111
Attachment D. See Appendix 0, previously submitted, for additiona11aboratory test results.
The RADON model was performed for the following cover section (from top to bottom):
• two feet compacted random fill (frost barrier);
• one foot compacted clay; and
• a minimum of three feet random fill occupying the freeboard space between the tailings
and clay layer (platform fill).
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The top one foot of the lower random fill, clay layer and two foot upper random fill are compacted
to 95 percent maximum dry density. The top riprap layer was not included as part of the soil
cover for the radon attenuation calculation.
The most current RADON modeling is included in Attachment F.
The results of the RADON modeling exercise, based on two different compaction scenarios, show
that the uranium tailings cover configuration will attenuate radon flux emanating from the tailings
to a level of 18.2 to 19.8 pCi/m2/sec. This number was conservatively calculated as it takes into
account the freeze/thaw effect on the uppermost part (6.8 inches) of the cover (Section 3.3.4).
The soil cover and tailing parameters used to run the RADON model, in addition to the RADON
input and output data files, are presented in Appendix D as part of the Radon Calculation brief(See
Appendix B in the Tailings Cover Design report, previously submitted in its entirety as Appendix
D) and the most current model included as Attachment F to this submittal. Based on the model
results, the soil cover design of six-foot thickness will meet the requirements of 40 CFR PaJi 192
and 10 CFR Part 40.
3.3.2.2 Empirical Data
Radon gas flux measurements have been made at the White Mesa Mill tailings piles over Cells 2
and 3 (see Appendix D). Currently Cell 2 is fully covered and Cell 3 is partially covered with
three to four feet of random fill. During the period 2004 through 2007, cell 2 was only partially
covered with such random fill. Radon flux measurements, averaged over the covered areas, were
as follows (Denison 2004-2008):
Table 3.3-1
Average Radon Flux from Tailings Cells 2004-2008
! 1:IUSERS\WMRC1'LNISECT031t<:v3.2.RPT,Jullc ~o I 0
(pCi/OI2/sec)
2004 2005 2006
Cell 2 13.9 7.1 7.9
Cell 3 10.8 6.2 10.0
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2007 2008
13.5 3.9
8.9 3.1
Empirical data suggest that the random fill cover, alone, is currently providing an effective barrier
to radon nux. Thus, the proposed tailings cover configuration, which is thicker, moisture
adjusted, contains a clay layer, and is compacted, is expected to attenuate the radon nux to a level
below that predicted by the RADON model. The field radon nux measurements confirm the
conservatism of the cover design. This conservatism is useful, however, to guarantee compliance
with applicable regulations under long term climatic conditions over the required design life of
200 to 1,000 years.
3.3.3 Infiltration Analysis
The tailings ponds at White Mesa Mill are lined with synthetic geomembrane liners which under
certain climatic conditions, could potentially lead to the long-term accumulation of water from
infiltration of precipitation. Therefore, thc soil cover was evaluated to estimate the potential
magnitude of infiltration into the capped tailings ponds. The Hydrologic Evaluation of Landfill
Performance (HELP) model, Version 3.0 (EPA, 1994) was used for the analysis. HELP is a quasi
two-dimensional hydrologic model of water movement across, into, through, and out of capped
and lined impoundments. The model utilizes weather, soil, and engineering design data as input
to the model, to account for the effects of surface storage, snowmelt, run-off, infiltration,
evapotranspiration, vegetative growth, soil moisture storage, lateral subsurface drainage, and
unsaturated vertical drainage on the specific design, at the specified location.
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The soil cover was evaluated based on a two-foot compacted random fill layer over a one-foot
thick, compacted clay layer. The soil cover layers were modeled based on material placement at a
minimum of 95 percent of the maximum dry density, and within two percent of the optimum
moisture content per American Society for Testing and Materials (ASTM) requirements. The top
riprap layer and the bottom random fill layer were not included as part of the soil cover for
infiltration calculations. These two layers are not playing any role in controlling the infilb'ation
through the cover material.
The random fill will consist of clayey sands and silts with random amounts of gravel and rock-size
materials. The average hydraulic conductivity of several samples of random fill was calculated,
based on laboratory tests, to be 8.87 x 10.7 cm/sec. The hydraulic conductivity of the clay source
from Section 16 was measured in the laboratory to be 3.7 x 10.8 cm/sec. Geotechnical soil
properties and laboratory data are presented in Appendix D.
Key HELP model input parameters include:
Blanding, Utah, monthly temperature and precipitation data, and HELP model default
solar radiation, and evapotranspiration data from Grand Junction, Colorado. Grand
Junction is located northeast of Blanding in similar climate and elevation;
Soil cover configuration identifying the number oflayers, layer types, layer thickness, and
the total covered surface area;
Individual layer material characteristics identifying saturated hydraulic conductivity,
porosity, wilting point, field capacity, and percent moisture; and
Soil Conservation Service runoff curve numbers, evaporative zone depth, maximum leaf
area index, and anticipated vegetation quality.
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Water balance resnlts, as calculated by the HELP model, indicate that precipitation would either
run off the soil cover or be evaporated. Thus, model simulations predict zero infiltration of
surface water through the soil cover, as designed. These model results are conservative and take
into account the freeze/thaw effects on the uppermost part (6.8 inches) of the cover (See Section
1.3 of the Tailings Cover Design report, Appendix D). The HELP model input and output for the
tailings soil cover are presented in the HELP Model calculation brief included in previously
submitted Appendix D.
As mentioned above, potential infiltration into the tailings cap is currently ebing remodelined in
the Infiltration Analysis. Any changes to this Plan that are required as a result of such remodeling
will be incorporated into a subsequent revision to this Plan.
3.3.4 Freeze/Thaw Evaluation
The tailings soil cover of one foot of compacted clay covered by two feet of random fill was
evaluated for freeze/thaw impacts. Repeated freeze/thaw cycles have been shown to increase the
bulk soil permeability by breaking down the compacted soil structure.
The soil cover was evaluated for freeze/thaw effects using the modified Berggren equation as
presented in Aitken and Berg (1968) and recommended by the NRC (U.S. Department of Energy,
1988). This evaluation was based on the properties of the random fill and clay soil, and
meteorological data from both Banding, Utah and Grand Junction, Colorado.
The results of the freeze/thaw evaluation indicate that the anticipated maximum depth of frost
penetration on the soil cover would be less than 6.8 inches. Since the random fill layer is two feet
thick, the frost depth would be confined to this layer and would not penetrate into the underlying
clay layer. The performance of the soil cover to attenuate radon gas flux below the prescribed
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standards, and to prevent surface water infiltration, would not be compromised. The input data
and results of the freeze/thaw evaluation are presented in the Effects of Freezing on Tailings
Covers Calculation brief included as Appendix E in the Tailings Cover Design report, which was
previously submitted as Appendix D.
3.3.5 Soil Cover Erosion Protection
A riprap layer was designed for erosion protection of the tailings soil cover. According to NRC
guidance, the design must be adequate to protect the soil/tailings against exposure and erosion for
200 to 1,000 years (NRC, 1990). CUITently, there is no standard industry practice for stabilizing
tailings for 1,000 years. However, by treating the embankment slopes as wide channels, the
hydraulic design principles and practices associated with channel design were used to design
stable slopes that will not erode. Thus, a conservative design based on NRC guidelines was
developed. Engineering details and calculations are summarized in the Erosion Protection
Calculation brief provided in Appendix F in the Tailings Cover Design report, which was
previously submitted as Appendix D.
Riprap cover specifications for the top and side slopes were determined separately as the side
slopes are much steeper than the slope of the top of the cover. The size and thickness ofthe riprap
on the top of the cover was calculated using the Safety Factor Method (NUREG/CR-465I , 1987),
while the Stephenson Method (NUREG/CR-465I , 1987) was used for the side slopes. These
methodologies were chosen based on NRC recommendations (1990).
By the Safety Factor Method, riprap dimensions for the top slope were calculated in order to
achieve a slope "safety factor" of 1.1. For the top of the soil cover, with a slope of 0.2 percent, the
Safety Factor Method indicated a median diameter (Dso) riprap of 0.28 inches is required to
stabilize the top slope. However, this dimension must be modified based on the long-term
durability of the specific rock type to be used in construction. The suitability of rock to be used as
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a protective cover has been assessed by laboratory tests to determine the physical characteristics of
the rocks (See Attachment H). The North pit source has an over sizing factor of 9.8S%. The
riprap sourced from this pit should have a DSO size of at least 0.31 inches and should have an
overall layer thickness of at least three inches on the top of the cover.
Riprap dimensions for the side slopes were calculated using Stephenson Method equations. The
side slopes of the cover are designed at SH: 1 V. At this slope, Stephenson's Method indicated the
unmodified riprap Dso of3.24 inches is required. Again, assuming that the NOlih pit material will
be used, the modified Dso size of the riprap should be at least 3.S4 inches with an overall layer
thickness of at least 8 inches.
The potential of erosion damage due to overland flow, sheetflow, and channel scouring on the top
and side slopes of the cover, including the riprap layer, has been evaluated. Overland flow
calculations were perfonned using site meteorological data, cap design specifications, and
guidelines set by the NRC (NUREGICR-4620, 1986). These calculations are included in
Appendix F of the Tailings Cover Design report (Appendix D previously submitted). According
to the guidelines, overland flow velocity estimates are to be compared to "permissible velocities,"
which have been suggested by the NRC, to determine the potential for erosion damage. When
calculated, overland f10w velocity estimates exceed permissible velocities, additional cover
protection should be considered. The permissible velocity for the tailings cover (including the
riprap layer) is S.O to 6.0 feet-per-second (ft.!sec.) (NUREGICR-4620). The overland flow
velocity calculated for the top of the cover is less than 2.0 ft.lsec., and the calculated velocity on
the side slopes is 4.9 ft.lsec. A rock apron will be constructed at the toe of high slopes and in areas
where runoff might be concentrated (See Figure A-S.I-4). The design of the rock aprons is
detailed in Attachment G.
3.3.6 Slope Stability Analysis
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Static and pseudostalic analyses were performed to establish the stability of the side slopes of the
tailings soil cover. The side slopes are designed at an angle of SF!: IV. Because the side slope
along the southern section of Cell 4A is the longest and the ground elevation drops rapidly at its
base, this slope was determined to be critical and is thus the focus of the stability analyses.
The computer software package GSLOPE, developed by MITRE Software Corporation, has been
used for these analyses to determine the potential for slope failure. GSLOPE applies Bishop's
Method of slices to identify the critical failure surface and calculate a factor of safety (FOS). The
slope geometry and properties of the construction materials and bedrock are input into the model.
These data and drawings are included in the Stability Analysis of Side Slopes Calculation brief
included in Appendix G of the Tailings Cover Design report. For this analysis, competent
bedrock is designated at 10 feet below the lowest point of the foundation [i.e., at a S,S40-foot
elevation above mean sea level (msl)]. This is a conservative estimate, based on the borehole logs
supplied by Chen and Associates (I 979), which indicate bedrock near the surface.
3.3.6.1 Static Analysis
For the static analysis, a Factor of Safety ("FOS") of 1.5 or more was used to indicate an acceptable
level of stability. The calculated FOS is 2.9 I, which indicates that the slope should be stable
under static conditions. Results of the computer model simnlations are included in Appendix G
of the Tailings Cover Design report.
3.3.6.2 Pseudostatic Analysis (Seismicity)
The slope stability analysis described above was repeated under pseudo static conditions in order to
estimate a FOS for the slope when a horizontal ground acceleration 0[0. I Og is applied. The slope
geometry and material properties used in this analysis are identical to those used in the stability
analysis. A FOS of 1.0 or more was used to indicate an acceptable level of stability under
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pseudostatie conditions. The calculated FOS is 1.903, which indicates that the slope should be
stable under dynamic conditions. Details of the analysis and the simulation results are included in
Appendix G of the Tailings Cover Design report.
In June of 1994, Lawrence Livennore National Laboratory ("LLNL") published a report entitled
Seismic Hazard Analysis of Title 11 Reclamation Plans, (Lawrence Livermore National
Laboratory, 1994) which included a section on seismic activity in southern Utah. In the LLNL
report, a horizontal ground acceleration of O.l2g was proposed for the White Mesa site. The
evaluations made by LLNL were conservative to account for tectonically active regions that exist,
for example, near Moab, Utah. Although, the LLNL report states that " ... [Blanding] is located in
a region known for its scarcity of recorded seismic events," the stability of the cap design slopes
using the LLNL factor was evaluated. The results of a sensitivity analysis reveal that when
considering a horizontal b'round acceleration of O.12g, the calculated FOS is 1.778 which is still
above the required value of 1.0, indicating adequate safety under pseudo static conditions. This
analysis is also included in Appendix G of the Tailings Cover Design report. A probabilistic
seismic risk analysis (See Attachment E) was performed in April 1999 during an evaluation of
cover stability.
3.3.7 Soil Cover-Animal Intrusion
To date, the White Mesa site has experienced only minor problems with burrowing animals. In
the long term, no measures short of continual annihilation oftarget animals can prevent burrowing.
However, reasonable measures will discourage burrowing including:
Total cover thickness of at least six-feet;
Compaction oftbe upper three feet of soil cover materials to a minimum of 95 percent, and
the lower three feet to 80-90 percent, based on a standard Proctor (ASTM D-698); and
Riprap placed over the compacted random fill material.
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3.3.8 Cover Material/Cover Material Volumes
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White Mesa Mill Reclamation Plan
Construction materials for reclamation will be obtained from on-site locations. Fill material will
be available from the stockpiles that were generated from excavation of the cells for the tailings
facility. If required, additional materials are available locally to the west of the site. A clay
material source, identified in Section 16 at the southern end of the White Mesa Mill site, will be
used to construct the one-foot compacted clay layer. Riprap material will be produced from
off-site sources.
Detailed material quantities calculations are provided in Attachment C, Cost Estimates for
Reclamation of White Mesa Mill Facilities, as part of the volume and costing exercise.
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30 RECI "MATr ON pi AN
This section provides an overview of the Mmill location and property; details the facilities to be
reclaimed; and describes the design criteria applied in this reelamatieft l"isftPJan. Reclamation
!!plans and ~Specifications are presented in Attachment A. Attachment B presents the quality
plan for construction activities. Attachment C presents cost estimates for reclamation.
Attachments 0 through H present additional material test results and design calculations to
SUppOl1 the rReclamation nPlan.
3.1 Location and Property Description
The White Mesa Mill is located six mi les south of Blanding, Utah on US Highway 191 on a parcel
of land encompassing all or part of Sections 21 , 22, 27, 28, 29, 32, and 33 of T37S, R22E, and
Sections 4, 5, 6, 8, 9, and 16 ofT38S, R22E, Salt Lake Base and Meridian described as follows
(Figure 3.1-1):
The south half of Section 21; the southeast quarter of the southeast quarter of
Section 22; the northwest quarter of the northwest quarter and Jots I and 4 of
Section 27 all that palt of the southwest quarter of the northwest qual1er and the
northwest quarter southwest qual1er of Section 27 lying west of Utah State
Highway 163; the northeast qual1er of the northwest quarter, Ihe south hal f of the
northwest quarter, the nOl1heast quarter and the south ha lf of Section 28; the
southeast quarter of the southeast quarter of Section 29; the east half of Section 32
and all of Section 33, Township 37 South, Range 22 East, Salt Lake Base and
Meridian. Lois I through 4, inclusive, the south half of the north half, the
southwest qualter, the west half of the southeast quarter, the west half of the east
half of the southeast quarter and the west half of the cast half of the east half of the
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southeast quarter of Section 4; Lots 1 through 4, inclusive, the south half of the
north half and the south half of Section 5 (all); Lots 1 and 2, the south half of the
northeast quarter and the south half of Section 6 (E1I2); the northeast quarter of
Section 8; all of Section 9 and all of Section 16, Township 38 South, Range 22 East,
Salt Lake Base and Meridian. Gonl8tni-ng---f-IpVo:;:·i-FnHl-2-1),',A,)';71"--fl-C,re-s/}sht!LQlEt1
L<,um .. 12-c (mlLQ.U_~,j.~h_y,,,::'t{L~,1jlL5,iudJ{t!J1l0 ___ 'rQH.~LJf!}lf_UJDJ £Ung~,,!J.r(;: JJPprmsjrrEi1£ly
),: ~U ,)_"i1<:Tg~,-
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White Mesa Mill Reclamation Plan
INSERT FIGURE 3.1-1
3.2 Facilities to be Reclaimed
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White Mesa Mill Reclamation Plan
See Figure 3.2-1 for a general layout of the mi ll yard and related facilities and the restricted area
boundary.
3.2.1 Summary of Facilities to be Reclaimed
The facilities to be reclaimed include the following:
_" __ ---cell I (evaporat ionve). Cell 1 was previously referred to as Cell 1-1. It is no~---
referred to as Cell 1 :,
_" _Cells 2 and 3, 4A and 4B (tailings); e.Ei Cell ~A (.el e.ffe.lly .seEi),
_" __ ---Mill buildings and equipment;;
_" __ -Gn-site contaminated areas' and;
_" __ ---Off-si te contaminated areas (i .c., potent ial areas affected by windblown tailings).
The reclamation of the above facilities will include the following:
Plaeement efmaterials Bnd tlebAs fram mHkleeemmissiafling-i~
Formatted: List Paragraph, Indent: Left:
0.25", Harl9irl9: 0.38", Bulleted + Level: 1 +
Aligned at: 0.75" + Indent at: 1~, Tab stops:
0.63", Left + Not at 0.5" + 0.75"
---Placement of contaminated soils, crystals, and synthetic liner material and any·---Formatted: list paragraph, Bulleted + level:
1 + Aligned at: 0.25" + Indent at: as
contaminated underlying soils from Cell I in!Q tailings -Cells ~A or 48.
_" _---I'leeement-ef'eoolftmiflftled seilO;-eFyStel5-8fld-syfl11letie-lffl8!'-lflelefiel-ffemtelJ-4.A-jfl
t&iIi~Hs+eRd+.
_" _--Placement ofa compacted clay liner on a pot1ion of the Cell 1 impoundment area to be
used for disposal of contaminated materials and debris fi'om the Mmill site
decommissioning. (the Cell 1-1 Tailings Area)
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!....--Placement of materials and debris from Mill Decommissioning into tailings Cells 4A
or 48 or in the Cell I Tailings Area:
_0 _Placement of an engineered multi-layer cover 6ft tke Cell 1 I Tailings AFea. 8Ha over the
entire area of Cells 2. 3. 4A and 48;; and the Cell I Tailings Area.
_0 _-Construction of runoff control and diversion channels as necessary~~
_o_--Reconditioning of Mmill and ancillary areas' and~
!....--Reciamal ion of borrow sources.
Formatted: List Paragraph, Bulleted + level:
1 + Aligned at: 0.25" + Indent at: OS'
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INSERT FIGURE 3.2-1
3.2.2 Tailings and Evaporative Cells
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The following subsections describe the cover design and reclamation procedures for Cells I-I, 2, 3,
1A... -and 4.6:A. Complete engineering details and text are presented in the Tailings Cover Design
report, Appendix D, previously submitted. Additional information is provided in Attachments 0,
E and F to this submittal.
)}}:. ~ ~oJ£ ~<!~e!.' p_e~ig'!. ______________________________________________ -i _ --{ Formatted: Foot: italiC
A six-foot thick soil cover ferIa be placed over the uranium tailings and mill decommissioning
materials in the Cell I-I Tailings Area, Ce112. Ce112, Ce114A and Ce11 48; was designed using
on-site materials that will contain ta ilings and radon emissions in compliance with regulations of
the United States NtleleaF Regl;l:latef) Cemmissiefl ("NRC the State of Utah,!!) and by reference,
the En"ifenmentai PFeteetiefl Agefle~ ("EPA!!). The cover consists of a one-foot thick layer of
clay, available from within the site boundaries (Section 16 or stockpiles on site), below two feet of
random fill (frost barrier), available from stockpiles on site. The clay is underlain by three feet
(minimum) random fill soi l (platform fill), also available on site. In addition to the soil cover, a
minimum three-inch (on the cover top) to 8-inch (on the cover slopes) layer of rip rap material will
be placed over the compacted random fill to stabilize slopes and provide long-term erosion
resistance (see Attachments 0 and H for characterization of cover materials).
Uranium tailings soil cover design requirements for regulatory compliance include:
Attenuate radon flux to an acceptable level (20 picoCuries-per meter squared-per second
[pCi/m'/sec]) (NRC, 1989) and 40 CFR 61.250-61.256;
Minimize infiltration into the reclaimed tailings cells;
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Maintain a design life of up to 1,000 years or to the extent reasonably achievable, and in
any case for at least 200 years; and
Provide long-term slope stability and geomorphic durability to withstand erosional forces
of wind, the pfObabJe maximum flood event, and a horizontal ground acceleration ofO.lg
due to seismic events.
Several models/analyses were utilized in simulating the soil cover effectiveness: radon flux
attenuation, hydrologic evaluation of infiltration, freeze/thaw effects, soil cover erosion
protection, and static and pseudostatic slope stability analyses, These analyses and results are
discussed in detail in Sections 3.3.1 through 3.3.5, and calculations are also shown in the Tailings
Cover Design report, (Appendix 0, Attachment E and Attachment F). The soil cover (from top to
the bottom) wi!! consist of: (1) minimum of three inches of riprap material; (2) two feet of
compacted random fill; (3) one foot of compacted clay; and (4) minimum three feet of compacted
random fill soil.
The final grading plan is presented in Section 5, Figure 5.1-1. As indicated on the figures, the top
slope of the soil cover will be constructed at 0.2 percent and the side slopes, as well as transitional
areas between celis, will be graded to five horizontal to one vertical (5H: 1 V).
A minimum of three feet random fill is located beneath the compacted fill and clay layers (see
cross-sections on Figures 5.1-2 and 5.1-3). The purpose of the fill is to raise the base of the cover
to the desired subgrade elevation. In many areas, the required fill thickness will be much greater.
However, the models and analyses presented in the Tailings Cover Design report (Appendix D)
were performed conservatively, assuming only a three-foot layer. Fol' modeling purposes, this
lower, random filJ layer was considered as part of the soil cover for performing the radon flux
attenuation calculation, as it effectively contributes to the reduction of radon emissions (see
Section 3.3.2.+). The fill was also evaluated in the slope stability analysis (see Section 3.3.6).
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However, it is not defined as part of the soil cover for other design calculations (infiltration,
freeze/thaw, and cover erosion).
)}}.:.?.. q,!.t! ! -! ______________________________________________________ ~ _ --{ Formatted: Font: Italic
Cell 1-1, used during mill operations solely for evaporation of process liquids, is the northemmost
existing cell and is located immediately west of the mill. It is also the highest cell in elevation, as
the natural topography slopes to the south. The drainage area above and including the cell is 216
acres. This includes drainage from the_-Mmill si te.
Cell 1-1 will be evaporated to dryness. The synthetic liner and raffinate crystals wil l then be
removed and placed in tail ings Cells ~A or 483. Any contaminated soils below the liner will be
removed and also placed in the tailings cells. Based on current regulatory criteria, the CUiTent
plan calls for excavation of the residual radioactive materials to be designed to ensure that the
concentration of radium-226 in land averaged over any area of 100 square meters does not exceed
the background level by more than:
_" _--5 pei/g, averaged over the first 15 cm of soil below the surface, and
!--15 pCi/g, averaged over a 15 cm thick layer of soil more than 15 cm below the
surface.
A pOl1ion of Cell I (i.e .. the Cell I Tailings AreaH, adjacent to and running parallel to the
downstream cell dike, will be used for permanent disposal of contaminated materials and debris
from the mi ll site decommissioning and windblown cleanup. The actual area ofCeH I-I Tailings
Area needed for storage of additional material will depend on the status ofCeIl 4A~and ;..48 at the
time of final mi ll decommissioning. A portion of the Mmill area decommissioning material may
be placed in Cell 4A~ or 483 if space is avail~tble, but for purposes of the reclamation design the
Formatted: list Paragraph, Indent: Hanging:
0.5", Bulleted + Level: 1 + Aligned at 0.75" +
Indent at: 1"
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entire quantity of contaminated materials from the -Mmill site decommissioning is assumed to be
placed in the Cell I Tai lings Area-I. This results in approximately 10 acres of the Cell l-l
Tailings Aarea and being utilized fo r permanent tailings storage. This Brea is refereE! to 85 the
Cell 1 I Teiliftgs AfeeThe remaining area of. Cell 1-1 will then be breached and converted to a
sedimentation basin. All runoff from the Cell 1-1 Tailings Area, the Mmi ll area and the area
immediately north ofeell 1-1 will be routed into the sedimentation basin and will discharge onto
the natural ground via the channel located at the southwest corner of the basin. The channel is
designed to accommodate the PMF flood.
The HEC·! model was used to determine the PMF and route the nood through the sedimentation
basin (Attachment G). The peak flow was determined to be ! ,344 cubic feet per second (cfs). A
20-foot wide channel will discharge the flow to the natural drainage. During the local storm PMF
event, the maximum discharge through the channel will be 1,344 cfs. The entire flood volume
will pass through the discharge channel in approximately four hou rs.
At peak flow, the velocity in the discharge channel wi ll be 7.45 feet per second (fps). The
maximum flow depth will be 1.45 feet. This wi ll be a bedrock channel and the allowable velocity
for a channel of this type is 8-10 fps, therefore no ri prap is required. A fi'ee board depth of 0.5 feet
will be maintain ed for the PMP event.
I )1,.2.:3.. C;f!.lf? ________________________________________________________ ---{ Formatted: Font: Italic
Cell 2 wi ll be filled with tailings and covered with a multi-layered engineered cover to a minimum
cover thickness of six feet. The final cover will drain to the south at a 0.2 percent gradient.
The cover will he as described in Section 3.2.2.1 above. and will consist ofa minimum of three feet
of random fill (platform fil1), followed by a clay radon barrier of one fool in thickness, and two feet
of upper random fil l (frost barrier) for protection of the radon barrier. A minimum of three inches
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of rack will be utilized as armor against erosion. Side slopes will be graded to a 5: 1 slope and will
have 0.67 feel (8 inches) cfrock armor protection.
J }:...2.:.1. <;~/! ~ ______________________________________________________ -i --1 Formatted: Font: Italic
Cell 3 will he fitled with tailings, debris and contaminated soil s and covered with the same
multi-layered engineered cover as Cell 2.
lI...2.:.~ <;~/! 1!J _______________________________________________________ 1---( Formatted: Font: Italic
Cell 4A will be filled with tailings debris and contaminated soils and covered with the same
multi-layered engineered cover as Cell 2 and Cell 3 .
.J.2:.2.;~ ~f!I! 1~ ________________ ~ _____________________________________ . ~' -{ Formatted: Font: Italic
Cell 4B will be filled with tailings debris and contaminated soils and covered with the same
multi-layered engineered cover as Cell 2. Cell 3 and Cell 48.
Cell1A "ill Be e',al3ef8tea te aFYfless afta the ef)stals, s)'flthetie lifter aftEi aft) eentaminatea seils
I3laeeEi in tailings. ~Ien eentsfflinstea fHsteFisls iN eell 4 A ailEes "ill he usea te retluee the
setlthem slef3es efCel1 3 (rem the eHFFent 3: 1 te S: 1. A 2QQ feet Ii jEte eFeseh anti eeclFeel£ ehaftnel
will aile .. clraiRage aflhe preeipilatisR whieh falls iR the Cell area aRB frem feelaimeclafeas aea .e
Cen area (See Attoeftment C, Figure A 5.1 1, and Seftien. D an<l-E}.
3.2.3 Mill Decommissioning
A general layout of the mill area is shown in Figure 3.2.3-1.
rage 3·1 2
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The uranium and vanadium sections, including ore reclaim, grinding, pre-leach, leach, ceo, SX,
and precipitation and drying circuits as well as the alternate feed circuit decontamination pads.
scale house. sample plant. truck shop and all other structures on site will be decommissioned as
follows:
All equipment including instrumentation. process piping, electrical control and switchgear, and
contaminated structures will be removed. Contaminated concrete foundations will be demolished
and removed or covered with soil as required. Uncontaminated equipment, structures and waste
materials from Mmill decommissioning may be disposed of by sale, transferred to other
companywowned fac ilities, transferred to an appropr iate offwsite solid waste site, or disposed of in
one of the tailings cells. Contaminated equipment, structures and 4cLwaste materials from Mmill
decommissioning, contaminated soils underlying the Mmill areas, and ancillary contaminated
materials will be disposed of in tailings Cell -4A~, Cell 48;, or the Cell 1_+ Tailings Area.~
other 11 el2) byproduct material on site will be disposcdof in Cell 4A or Cell 48.
Debris and scrap will have a maximum dimension 0[20 feet and a maximum volume of 30 cubic
feet. Material exceeding these limits wi ll be reduced to within the acceptable limits by breaking,
cutting or other approved methods. Empty drums, tanks or other objects having a hollow volume
greater than five cubic feet will be reduced in volume by at least 70 percent. If vo lume reduction
is not feasible, openin gs shall be made in the object to allo w soils or other approved material to
enter the object.
Debris and scrap will be spread across the designated areas to avoid nesting and to reduce the
volume of voids present in the placed ma ss. Stockpiled soi ls, and/or other approved material
shall be placed over and into the scrap in sufficient amounts to fill the void s between the large
pieces and the volume within the hollow pieces to form a coherent mass.
See also Section 3.1 of Attachment A.
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The estimated reclamation costs for surety are set out in Attachment C. Attachment C will be
reviewed and undated on a yearly basis.
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[NSERT F[GURE 3.2.3-[
LAYOUT OF M[LL YARD AND ORE PAD
Page3-15
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l.f:):.~ t:!J.ll ~i!r:.. _____________________________________________________ ~ _ -1 Formatted: Font: Italic
Contaminated areas on the Mmill site will he primarily superficial and includes the orc storage
area and surface contamination of some roads. All orc will have been previously removed from
the orc stockpile area or will be transported and disposed of as contaminated material. All
contaminated materials will be excavated and be disposed in one of the tailings cells. The depth
of excavation will vary depending on the extent of contamination and will be governed by the
criteria in Attachment A, Section 3.2.
Windblown material is defined as Mmill ·derived contaminants dispersed by wind to surrounding
areas. Windblown contaminated material detected by a gamma survey usi ng the criteria 111
Attachment A, Section 3.2, will be excavated and disposed in one of the tai lings cells.
Disturbed areas will be covered, graded and vegetated as required. The proposed grading plan for
the Mmill site and ancillary areas is shown on Figu re A·3.2-1 in Attachment A.
3.3 Design Criteria
The design eriterie slimmories in tHis seetien ere ede~ted frem Tailings C6\ er Design. White Mesa
Mill (Titan, 1996). A eeJ3) ef the Tailings Ce. er Design reJ3ert is inellided as t\J3pendin D,
J3re, .. ielisl) slibmitted. It eentains 811 ef the ealelilatiefls lised iR design diselissed in this seetieR.
AdditieRal design iRfermetien is inellided in Attaehments D dlr6ligh H te this su&mtttehAs
required by Part I.H.l of the GWDP. Denison is in the process of completing an infiltration and
contamination transport model of the final tailings cover system to demonstrate the long-term
ability of the cover to protect nearby groundwater quality. Upon review of such modeling, the
executive Secretary will determine if changes to the cover systems as set outin the iPlan are needed
to ensure compliance with the performance criteria contained in part 1.0.8 of the GWOP.
Although the modeling has not been completed. modeling results to date suggest that some
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changes to the final cover design as set out in this Plan will be needed. However as the details of
such fe-design have not been finalized at this time. the approved 2000 cover deiagn and basis will
continue to be used for this version of the Plan. This Plan will be amended in the future to
incorporate any changes to the design of the tailings cover system that result from the current
modeling effort.
The design criteria summaries in this section are adapted from Tailings Cover Design, Mill (Titan,
1996), A copy of the Tailings Cover Design report is included in Appendix D, previously
submitted. It contains all of the calculations used in design discussed in this section. Additional
design information is included in Attachments D through H to this submittaL
3.3.1 Regulatory Criteria
Information contained in 10 CFR Pal1 20, Appendix A, 10 CFR Part 40, and Appendix A to IO
CFR Part 40 (which are incornorated by reference into UAC R313-24-41, and 40 CFR Part 192
was used as cri teria in final designs under th is Preelamatien "Ian. In addition, the following
documents also provided gu idance:
• en, irenmeRtal PFeteetien Ageney (EPA}, 1994, f!~~ J-!y!'!..·oJ9gJtE _ ~\~a!l!..a!i2!!. _ o.f:..~,,": formatted: Font: Italic
Landjill --Pellol'lI/ance (HELP) Model, Version 3,_-" -EPA/600IR-941168b,
September~,:
• Nu.I •• , Regul.to,y Commission (NRC), 1989, "Regulatory Guide 3.64 (Task
Formatted: list Paragraph, Bulleted + level:
1 + Aligned at: 0.25" + Indent at: 0.5"
WM·503·4) .c;.(!..k:.l!..'f}.t{O!l_ oj_~a!I<}J~ f{II::."(_1t~e!..1'!(!..t~0!.J}y_ E..('l"tjl!'2 y!"ql~i!..{/!I-'v!tj'_ '[(,!"~.,!2.§ _, ... ' -{ Formatted: Font: Italic
Covers.~ March~,:
!....--NRC. 1980. ffll!oj §~(lf£r~C£/I!J£c:.IJ:'O}iJLO!.t J.!.e![g~I_o[ §tC!.siO!'_ ~/:o!.e_c~ir~/!. ~<}I!.e!"~lo!" ___ -1 Formatted: Font: Italic
Stabilization of Uranillm Mill Tailings Sites.!! August~:-
!....--NUREGICR-4620, Nelson, J. D., Abt, S. R., et. aI., 1986, ~,,!€lb~(!o!'!E!~s_[Ol' ___ --l, 'ormatted, 'on" Ita'<
Evaillating LOl/g· Term Stabilization Desigm of Urani/fm Mill Tailings
Im polllldmellts,!! June~,:
Page 3-17
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_0 _ --NUREGICR-465I , 1987, fI2~,,-elop1,~e!J~ oJ.-lypl:ap_f!e..s[g;l_ C;.'~IE~if.l2t fiip.!"f!12 !~s../~lg_ ~ ~ -{ Formatted: Font: Italic
in Fllimes: Phase I ,.!! May~:"
~--U. S. Department of Energy, 1988, f Me..C! _of !,!·'!.e!~lg_ f!.1'1f'_ !1!{~w.J'!.g 2!! _l.!A:f!!51_. ;; -{ Formatted: Font: Italic
Covers,!! Albuquerque, New Mexico, October' and.
• NUREG 1620. 2003 §1!.IIU!.ard R..e~i~w PIa" /jJr l"e review _off! reclm1!0tio!, _Plan (p!' "1.iII_ ....... -{ Formatted: Font: Italic
Tailings Sites Under Title II oOlie Ural/flllll Mill Tailings radiatioll Colllrol Act 0(1978.
As mentioned above. the requirements set out in Part I.D.8 of the GWDP require that the cover
system for each tailings cell will be designed and constructed to meet the following minimum
requirements for a period of not less than 200 years:
• Minimize the infiltration of precipitation or other surface water into the tailings. including·
but not limited to the radon barrier:
• Prevent the accumulation of leachate head within the tailings waste layer that could rise
above or over-top the maximum FML elevation internal to any disposal cell. i.e. create a
--bathtub-' effect' and
• Ensure that groundwater quality at the compliance monitoring wells cleosn ot exceed the
GWOSs or GWCLs specified in Part Le.I and table 2 of the GWDP,
Upon completion of the Infiltration Analysis. this Plan will be revised as necessary to ensure
compliance with these requirements.
3.3.2 Radon Flux Attenuation
The "". i,.""'."tal P,o'.e,ioR AgeRe)' (EP A1 rules in 40 C.e. or Feee,al R.g"la'i." (CFR) Part
192 require that a "uranium tailings cover be designed to produce reasonable assurance that the
radon-222 release rate would not exceed 20 pCi/m2/sec for a period of 1,000 years to th e extent
Formatted: List Paragraph, Indent: Left:
0.25", Hanging: 0.25", Bulleted + level: 1 +
Aligned at: 0.25" + Indent at: 0.75", Tab
stops: Not at 0.75"
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reasonably achievable and in any case for at least 200 years when averaged over the disposal area
over at least a one year period" (N Re, 1989). NRC regulations presented in 10 CFR Part 40
(incomorate by reference into UAC R313-24-4l also restrict radon flux to less than 20 pCi/m2/sec.
The following sections present the analyses and design for a soil cover which meets this
requirement.
JJ:..2.:.~ r~e!ILcliXf!.IJ!!J!-'tsjs.. _____________________________________________ :.;-_< Formatted: Font: Italic
Formatted: Widow/Orphan control
The soil cover for the tailings cells at White Mesa Mill was evaluated for attenuation of radon gas·---1 Formatted: Widow/Orphan control
using the digital computer program, RADON, presented in the NRC's Regulatory Guide 3.64
(Task WM 503-4) entitled f{:!l£c~/£a!Jp'.!. _of j?!.ltjC!.l~ f{l ~r_!J.r!.el'IYf.!ll0.!l_ 0/.. §(.!':!~e.!l_ f!r.a.!lil!!'~ }{i{I ___ -1 Formatted: Font: Italic
Tailillgs Covers.!! The RADON model calculates rad on-222 flux attenuation by mult i-layered
eal1hell uranium mi ll tailings covers, and determines the minimum cover thickness required to
meet NRC and EPA standards. The RADO N model uses the follow ing soil properties in the
calculation process:
_0 _ ---Soi l layer thickness [centimeters (em)];
_0 _---Soil porosity (percent);
_0 _---Density [grams-per-cubic centimeter (gm/cmJ)];
_0 _---Weight percent moisture (percent);
_0 _---Radium activity (piC/g);
!........---Radon emanation coefficient (unit less); and
_0 _---Diffusion coefficient [square centimeters-per-second (cm2/sec)].
Physical and radiological propel1ies for tailings and random fill were analyzed by Chen and
Associates (1987) and Rogers and Associates (1988). Clay phys ical data from Section 16 was
analyzed by Advanced Tma Testing (1996) and Rogers and Associates (1996). Additional
testing of cover materials was performed in April 1999. The test results are included in
Formatted: list Paragraph, Indent Hanging:
O.75~. Blslleted + Level: 1 + Aligned at 1-+
Indent at: 1.25"
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White Mesa Mill Reclamation Plan
Attachment D. See Appendix 0, previously submitted, for additional laboratory test results.
The RADON model was performed for the following cover section (from top to bottom):
The top one foot of the lower random fill, clay layer and two foot upper random fill are compacted
to 95 percent maximum dry density. The top riprap layer was not included as part of the soil
cover for the radon attenuation calculation.
The most current RADON modeling is included in Attachment F.
The results of the RADON modeling exercise, based on two different compaction scenarios, show
that the uranium tailings cover configuration will attenuate radon flux emanating from the tailings
to a level of 18.2 to 19.8 pCilm2/sec. This number was conservatively calculated as it takes into
account the freeze/thaw effect on the uppermost part (6.8 inches) of the cover (Section 3.3.4).
The soil cover and tailing parameters used to run the RADON model, in addition to the RADON
input and output data files, are presented in Appendix 0 as part of the Radon Calculation brief(See
Appendix B in the Tailings Cover Design report, previously submitted in its entirety as Appendix
D) and the most current model included as Attachment F to this submittal. Based on the model
results, the soil cover design of six-foot thickness will meet the requirements of 40 CFR Part 192
and 10 CFR Part 40.
Formatted: List Paragraph, Indent: left:
OS', Bulleted -/. Level: 1 + Aligned at: 1" +
Indent at: 1.25", Tab stops: 0.56", Left +
0.88", Left + Not at 0.75"
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J'}}.:.?J}l!.lp{t~C[!U!f!I!1 ________________________________________________ ~..:-,: Formatted: Font: Italic
Radon gas flux measurements have been made at the White Mesa Mill tailings piles over Cells 2
and 3 (see Appendix D). Currently t!:lese eells ftfeCell 2 is fully covered and Cell 3 is partially
covered with th ree to four feet of random fill. During the period 2004 through 2007 cell 2 was
only partially covered with such random fill. Radon flux measurements, averaged over the
covered areas, were as follows (HN 1991 1996, IUC 1997 1998Denison 2004-2008):
Formatted: Widow/Orphan control, Keep with
''',,''
1991 _____________________________________________ 1995 _____ "'~ -},:Fo;;'.;;m;:'.;;""";:;;'.;;F;;on;:t,,' Bo;:;:"'-_____ --\
Fornlatted: Centered 199i 1997
~1-12>!----77._'l-j7 ptiIm'I". 6.1 pCitm 111/5 ... ". ---I144';.2~~I>CCili/flJl';'2!11"!ie".>----'7h.441'~'{C;;i"/mohl2,!oI!i",'''' -
C.1I3
9,8-pQ!fl>21 ...
7.S pCitn'~/!iee llA pCilm~'''/s".".--'"1f<4h'.55-tl~~C;;'h'''"'''2i!,'''s .. ee ... -22;3~.3-8
pCilmllseeTable 3.3-1
Average Radon Flux from Tailings Cells 2004-2008
(pCi/m2/sec)
~~~_7._~ _________ ~20~M~ ________ ~2~OO_5 ________ -+2~O~06 __________ ~20~O~7 ________ ~2~OO~8_-_-_-_--1-__ ~::
CcIl 2 _____ W ______ U _______ 'L2 _______ .!.U _______ U _________ ,:~:,
~~~----_+~~------_t~c_------~~~------~~--------~~------_+ \~\\ Cell 3 ____ J.~Jt _____ 2J ______ JQ.Q ______ ~.~ ______ }.:'_______ ,,,,1\\' L ____ -' _____ -'-_____ ..L _____ .L _____ L ____ -' - --~~~::~\' ,
,
, ,
\ ,-,\1 \
Iltll"
"JlIII
\1-"1
1I~\\ , Empirical data suggest that the random fil l cover, alone, is currently providing an effective barrier p\III , 11111
to radon flux. Thus, the proposed tailings cover configuration, which is thicker, moisture
adjusted, contains a clay layer, and is compacted, is expected to attenuate the radon nux to a level
, , \1\\\
\11\ ," ," " ,
" " " ,
"
Formatted: Font: 11 pt, Bold
formatted Table
Fornlatted: Font: Bold
formatted: Font: 11 pt, Bold
Fomlatted: Font: Bold
Formatted: Font: 1l pt, Bold
Formatted: Font: 11 pt, Bold
Formatted: Font: Bold
Formatted: Font: Bold
Fonnatted: Font: 11 pt, Bold
Formatted: Font: Bo~ below that predicted by the RADON model. The field radon flux measurements confirm the
conservatism of the cover design. This conservatism is useful, however, to guarantee compliance
with NRG-applicable regulations under long term climatic cond itions over the required design life
\'J Formatted: Font: 11 pt, Bold
\1 Formatted: Font: Bold
1 Formatted: Font: Bold
of 200 to 1,000 years.
3.3.3 Infiltration Analysis
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The tailings ponds at White Mesa Mill are lined with synthetic geomembrane liners which under
certain climatic conditions, could potentially lead to the long~term accumulation of water from
infiltration of precipitation. Therefore, the soil cover was evaluated to estimate the potential
magnitude of infiltration into the capped tailings ponds. The Hydrologic Evaluation of Landfil!
Performance (HELP) model, Version 3.0 (EPA, 1994) was used for the analysis. HELP is a quasi
two~djJ1lensional hydrologic model of water movement across, into, through, and OLit of capped
and lined impoundments. The model utilizes weather, soil, and engineering design data as input
to the model, to account for the effects of surface storage, snowmelt, run-off, infiltration,
evapotranspiration, vegetative growth, soil moisture storage, latera! subsurface drainage, and
unsaturated vertical drainage on the specific design, at the specified location.
The soil cover was evaluated based on a two-foot compacted random fill layer over a onc·foot
thick, compacted clay layer. The soil cover layers were modeled based on material placement at a
minimum of 95 percent of the maximum dry density, and within two percent of the optimum
moisture content per American Society for Testing and Materials (ASTM) requirements. The top
riprap layer and the bottom random fill layer were not included as part of the soil cover for
infiltration calculations. These two layers are not playing any role in controlling the infiltration
through the cover material.
The random t1!1 will consist of clayey sands and silts with random amounts of gravel and rock-size
materials. The average hydraulic conductivity of several samples of random fill was calculated,
based on laboratory tests, to be 8.87 x 10-7 em/sec. The hydraulic conductivity of the clay source
from Section 16 was measured in the laboratory to be 3.7 x 1O-s em/sec. Geotechnical soil
properties and laboratory data are presented in Appendix D.
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Key HELP model input parameters include:
Blanding, Utah, month ly temperature and precipitation data, and HELP model default
so lar radiation, and evapotranspiration data from Grand Junction, Colorado. Grand
Junction is located northeast of Blanding in similar climate and elevation;
Soil cover configuration identifying the number of layers, layer types,layer thickness, and
the total covered surface area;
Individ ual layer material characteristics identifying saturated hydraulic conductivity,
porosity, wilting poi nt, field capacity, and percent moisture; and
Soil Conservation Service runoff curve numbers, evaporative zone depth, max imum leaf
area index, and anticipated vegetation quality.
Water balance results, as calculated by the HELP model, indicate that precipitation would either
run_-off the soi l cover or be evaporated. Thus, model simu lations predict zero infiltration of
surface wa ler through the soil cover, as des igned. These model results are conservative and take
into account the freeze/thaw effects on the uppermost part (6.8 inches) oflhe cover (See Sect ion
1.3 oflhe Tailings Cover Design report, Appendix D). The HELP model input and output for the
tailings soil cover are presented in the HELP Model calculation brief included in previously
submitted Appendix D.
As mentioned above. potential infiltration into the tailings cap is currently ebing remodelined in
the Infiltration Analysis. Any changes to this Plan that are required as a result of such remodeling
will be incomorated into a subsequent revision to this Plan.
3.3.4 Freeze/Thaw Evaluation
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The tailings soil cover of one foot of compacted clay covered by two feet of random fill was
evaluated for f)'ceze/thaw impacts. Repeated freeze/thaw cycles have been shown to increase the
bulk soil permeability by breaking down the compacted soil structure,
The soil cover was evaluated for f)'ceze/thaw effects using the modified Berggren equation as
presented in Aitken and Berg (1968) and recommended by the NRC (U.S. Department of Energy,
1988). This evaluation was based on the properties of the random fill and clay soil, and
meteorological data from both Banding, Utah and Grand Junction, Colorado.
The results of the freeze/thaw evaluation indicate that the anticipated maximum depth of fl'ost
penetration on the soil cover would be less than 6.8 inches. Since the random fill layer is two feet
thick, the frost depth would be confined to this layer and would not penetrate into the underlying
clay layer. The performance of the soil cover to attenuate radon gas flux below the prescribed
standards, and to prevent surface water infiltration, would not be compromised. The input data
and results of the freeze/thaw evaluation are presented in the Effects of Freezing on Tailings
Covers Calculation brief included as Appendix E in the Tailings Cover Design report, which was
previously submitted as Appendix D.
3.3.5 Soil Cover Erosion Protection
A riprap layer was designed for erosion protection of the tailings soil cover. According to NRC
guidance, the design must be adequate to protect the soil/tailings against exposure and erosion for
200 to 1,000 years (NRC, 1990). Currently, there is no standard industry practice for stabilizing
tailings for 1,000 years. However, by treating the embankment slopes as wide channels, the
hydraulic design principles and practices associated with channel design were used to design
stable slopes that will not erode. Thus, a conservative design based on NRC guidelines was
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developed. Engineering details and calculations arc summarized in the Erosion Protection
Calculation brief provided in Appendix F in the Tailings Cover Design report, which was
previously submitted as Appendix D.
Riprap cover specifications for the top and side slopes were determined separately as the side
slopes arc much steeper than the slope oflhe top oflhe cover. The size and thickness oflhe riprap
on the top oflhe cover was calculated using the Safety Factor Method (NUREGICR-4651 , 1987),
while the Stephenson Method (NUREG/CR-465I > 1987) was used for the side slopes. These
methodologies were chosen based on NRC recommendations (1990).
By the Safety Factor Method, riprap dimensions for the top slope were calculated in order to
achieve a slope "safety factor" of 1.1. For the top of the soil cover, with a slope of 0.2 percent, the
Safety Factor Method indicated a median diameter (050) riprap of 0.28 inches is required to
stabilize the top slope. However, this dimension must be modifICd based on the long~tcrm
durability of the specific rock type to be used in construction. The suitabil ity of rock to be used as
a protective cover has been assessed by laboratory tests to determine the physical characteristics of
the rocks (See Attachment H). The North pit source has an over sizing factor of 9.85%. The
riprap sourced from this pit should have a 050 size of at least 0.31 inches and should have an
overall layer thickness of at least three inches on the top of the cover.
Riprap dimensions for the side slopes were calculated using Stephenson Method equations. The
side slopes of the cover are designed at 5H:l V. At this slope, Stephenson's Method indicated the
unmodified riprap D50 of3.24 inches is required. Again, assuming that the North pit material wil!
be used, the modified 0 50 size of the riprap should be at least 3.54 inches with an overall layer
thickness of at least 8 inches.
The potential of erosion damage due to overland flow, sheetflow, and channel scouring on the top
and side slopes of the cover, including the riprap layer, has been evaluated. Overland flow
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calculations were performed using site meteorological data, cap design specifications, and
guidelines set by the NRC (NUREG/CRA620, 1986), These calculations arc included in
Appendix F of the Tailings Cover Design report (Appendix D previously submitted). According
to the guidelines, overland flow velocity estimates arc to be compared to "permissible velocities,"
which have been suggested by the NRC, to determine the potential fOf erosion damage. When
calculated, overland flow velocity estimates exceed permissible velocities, additional cover
protection should be considered. The permissible velocity for the tailings cover (including the
riprap layer) is 5.0 to 6.0 feet-per-seeond (fUsee.) (NUREG/CR-4620). The overland flow
velocity calculated for the top of the cover is less than 2.0 ft.lsec., and the calculated velocity on
the side slopes is 4.9 fLlsec. A rock apron will be constructed at the toe of high slopes and in areas
where runoff might be concentrated (Sec Figure A-5.1-4). The design of the rock aprons is
detailed in Attachment G.
3.3.6 Slope Stability Analysis
Static and pseudostatic analyses were performed to establish the stability of the side slopes of the
tailings soil cover. The side slopes are designed at an angle of 5 H: I V. Because the side slope
along the southel.-n section of Cell 4A is the longest and the ground elevation drops rapidly at its
base, this slope was determined to be critical and is thus the focus of the stability analyses.
The computer software package GSLOPE, developed by MITRE Software Corporation, has been
used for these analyses to determine the potential for slope failure. GSLOPE applies Bishop's
Method of slices to identify the critical failure surface and calculate a factor of safety (FOS). The
slope geometry and properties of the construction materials and bedrock are input into the model.
These data and drawings are included in the Stability Analysis of Side Slopes Calculation brief
included in Appendix G of the Tailings Cover Design report. For this analysis, competent
bedrock is designated at 10 feet below the lowest point of the foundation [i.e., at a 5,540-foot
elevation above mean sea level (msl)]. This is a conservative estimate, based on the borehole logs
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supplied by Chen and Associates (1979), which indicate bedrock near the surface.
]2J .... 6;.{§tpl.!':.1'!(!.ly s'j.s.. ______________ . _____________________ .. ___________ . ~~-_{Formatted:Font Italic
For the static analysis, a Factor of Safety ("FOS ") of 1.5 or more was used to indicate an acceptable
level of stability. The calculated POS is 2.91, which indicates that the slope should be stable
under static conditions. Results of the computer model simulations are included in Appendix G
of the Tailings Cover Design report.
The slope stability analysis described above was repeated under pseudostatic conditions in order to
estimate a FOS for the slope when a horizontal ground acceleration ofO.10g is applied. The slope
geometry and material properties used in this analysis are identical to those used in the stability
analysis. A FOS of 1.0 or more was used to indicate an acceptable level of stability under
pseudostatic conditions. The calculated FOS is 1.903, which indicates that the slope should be
stable under dynamic conditions. Detai Is of the analysis and the simulation results are included in
Appendix G of the Tailings Cover Design report.
In June of 1994, Lawrence Livermore National Laboratory ("LLNL") published a repoli entitled
J<!/J.''.!Cc _ f(a?a.!~1 _ d'.!f!JY'<'js... _01_ '['f!IE _ £1_ !}Ec:..lq'~lqtjo.!~ '?j~}~S,-Jb~':Y!~e!l~e __ l:.i~~J'~n2~e_ }!a~i9l.:!<!.I_ r r -i Formatted: Font: ItaliC, No underline
Laboratory, 1994) which included a section on seismic activity in southern Utah. In the LLNL
report, a horizontal ground acceleration of 0.12g was proposed for the White Mesa site. The
evaluations made by LLNL were conservative to account for tectonically active regions that exist,
for example, near Moab, Utah. Although, the LLNL report states that " ... [Blanding] is located in
a region known for its scarcity of recorded seismic events," the stability of the cap design slopes
using the LLNL factor was evaluated. The results of a sensitivity analysis reveal that when
considering a horizontal ground acceleration ofO.12g, the calculated FOS is 1.778 which is still
Page 3-27
Revision 3.,2G
mtel'flflt-ionaWJ'fmiumDcnison Mines (USA) Corp~eJ'fH.j.0n
White Mesa Mill Reclamation Plan
above the required value of 1.0, indicating adequate safety under pseudostatic conditions. This
analysis is also included in Appendix G of the Tailings Cover Design report. A probabilistic
seismic risk analysis (See Attachment E) was performed in April 1999 during an evaluation of
cover stability.
3.3.7 Soil Cover·Animallntrusion
To date, the White Mesa site has experienced only minor problems with burrowing animals. In
the long term, no measures short of continual annihilation oftargct animals can prevent burrowing.
However, reasonable measures will discourage burrowing including:
Total cover thickness of at least six~feet;
Compaction of the upper three feet of soil cover materials to a minimum of95 percent, and
the lower three feet to 80~90 percent, based on a standard Proctor (ASTM D-698); and
Riprap placed over the compacted random fill material.
3.3.8 Cover Material/Cover Materia! Volumes
Construction materials for reclamation will be obtained from on~site locations. Fill material wi!!
be available from the stockpiles that were generated from excavation of the cells for the tailings
facility. If required, additional materials are available locally to the west of the site. A clay
material source, identified in Section 16 at the south em end of the White Mesa Mill site, will be
used to construct the one~foot compacted clay layer. Riprap material will be produced from
off-site sources.
Detailed material quantities calculations arc provided in Attachment C, Cost Estimates for
Reclamation of White Mesa Mill Facilities, as part of the volume and costing exercise.
a)ENISONr)~~
MINES
Denison Mines (USA) Corp.
1050 17th Stree~ Suite 950
Oenver. CO 80265
USA
Tel : 303 628·7798
fIX: 303 389-4125
www.dtnilonmin ... com
White Mesa Mill Reclamation Plan
Revision 3.2
White Mesa Mill and Tailings
Management System
June 2010
State of Utahlle.(2) Byproduct Material License # UT1900479
Denison Mines (USA) Corp.
www.denllonmln ••. com
1050 17th Streot, Suito 950
Oenver, CO, USA 80285
rei : 303628·7798
Fa. : 303 389-4125
DENISONI)~~
MINES
Denison Mines (USA) Corp.
1050 171h Stree~ Suit. 950
Oenver, CO 80265
USA
rei: 303 628·7798
Fax: [phone]
WWW.dlnisonmlnll.com
White Mesa Mill Reclamation Plan
Revision 3.2
Figures
White Mesa Mill and Tailings
Management System
June 2010
State of Utahlle.(2) Byproduct Material License # UT1900479
Denison Mines (USA) Corp,
www.deniaonmln ••. com
1050 17th Street, Suite 950
Denver, CO, USA 80265
rei: 303 628·7798
Fax: [phone]
(
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SCALE IN FEET
EXPLANATION
MN.2Q pard1ad monHOIing well showing
• 5449 elevation In feet amsl
0 5512
PIEZ-1
~ 5552
M'W-S1 -+-54 ••
-¢-5525
temporary perched monitoring well
showing elevation In feet amsJ
perched piezometer showing
el.va~on In feet omsl
perched monitoring wall. installed In 2005
&howing elevation in reet elmsl
lemporary pen.:hed fflOllitoring well ill$lalh:d
In 2005 showing elevation In faet amsl
HYDRO
GEO
CHEM, INC.
-----5440_ --
___ 5420-
~_ 4 -7 ---:::--II __ == -==_ II -=7;
~ I~
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,-)'
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APPROXIMATE ELEVATION OF
TOP OF BRUSHY BASIN
(Contours Generated by Kriging)
DATE IrtCr(rrt:IIlCE
H ,71 SOOO/hydrp t09!bbelOSrev .srt
~
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1.5-2
OENISONI)~~ Cenison Minos (USA) Corp.
1050 17th Stroot Suite 950
Denver. CO 80265
USA
MINES
Attachment C
Tei: 303 628·7798
Fax: [phone]
www.dlnlsonmines.com
White Mesa Mill Reclamation Plan
Revision 3.2
Revised Cost Estimates
for
Reclamation
of the
White Mesa Mill and Tailings
Management System
June 2010
State of Utahl1e.(2) Byproduct Material License # UT1900479
Denison Mines (USA) Corp.
www.denlsonmines.com
1050 17th Street. Suite 950
Denver, CO, USA 80265
Tel: 303 628·7798
Fax : [phone]
WHITE MESA MILL RECLAMATION COST ESTIMATE
June 2010
Revision 3.2
Mill Decommissioning $2,069,337
Cell 1 $1,696,333
Cell 2 $1,579,075
Cell 3 $2,041,413
Cell4A $1,336,754
Cel14B $1,325,780
Miscellaneous $2,722,977
Subtotal Direct Costs $12,771,669
Profit Allowance 10.00% $1,277,167
Contingency 15.00% $1,915,750
Licensing & Bonding 2.00% $255,433
UDEQ Contract Administration 4.00% $510,867
Contractors Equipment Floater $82,250
General liability Insurance 0.45% $57,473
Long Term Care Fund $797,448
Total Reclamation $17,668,057
Revised Bond Amount $17,668,057
Denison Mines (USA) Corp.
6/29/2010 -2:34 PM -WMM Rec Plan Est June 2010 Rev 3.2 White Mesa Mill
RECLAMATION OF CELL 4A
Dewatering of Cell 4A
Resource Description
Dewatering of Cell 4A
Total Dewatering of Cell 4A
Place Bridging (Platform) Lift
Resource Description
Cat 637 Scraper
Cat 637 Scraper Operators
Cat 825 Compactor
Cat 825 Compactor Operator
Cat D8N Dozer With Ripper
Cat D8N Dozer Operator
Cat 07 Dozer
Cat 07 Dozer Operator
Cat 651 Waterwagon
Cat 651 Waterwagon Operator
Cat 14G Motorgrader
Cat 14G Motorgrader Operator
Equipment Maintenance (Buller)
Total Place Bridging (Platform) Lift
Place Lower Random Fill
Resource Description
Equipment Operators
Cat 637 Scraper
Cat 825 Compactor
Cat D8N Dozer With Ripper
Cat 07 Dozer
Cat 651 Waterwagon
Cat 14G Motorgrader
Equipment Maintenance (Buller)
Total Place Lower Random Fill
Clay Layer
Resource Description
Equipment Operators
Cat 637 Scraper
Cat 825 Compactor
Cat D8N Dozer With Ripper
Cat 07 Dozer
Cat 651 Waterwagon
Cat 14G Motorgrader
Cat 980 Loader
5000 Gallon Water Truck
Highway Trucks
Truck Drivers
Equipment Maintenance (Butler)
Total Place Clay Layer
WMM Rec Plan Est June 2010 Rev 3.2
Ihrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
Units Cost/Unit Task Units Task Cost
1 $0.481 62,4001 $30,0001
$30,000
Units Cost/Unit Task Units Task Cost
$205.10 671 $137,545
$17.72 671 $11,881
$93.85 168 $15,735
$13.09 168 $2,194
$94.96 168 $15,921
$13.09 168 $2,194
$80.38 168 $13,476
$13.09 168 $2,194
$107.49 168 $18,020
$16.67 168 $2,795
$70.59 168 $11,834
$18.91 168 $3,170
$20.53 2,850 $58,520
$295,481
Units Cost/Unit Task Units Task Cost
$18.94 882 $16,698
$205.10 392 $80,370
$93.85 98 $9,194
$94.96 98 $9,303
$80.38 98 $7,874
$107.49 98 $10,530
$70.59 98 $6,915
$20.53 882 $18,103
$158,986
Units Cost/Unit Task Units Task Cost
$18.94 1,060 $20,075
$205.10 0 $0
$93.85 200 $18,771
$94.96 180 $17,094
$80.38 0 $0
$107.49 180 $19,347
$70.59 200 $14,118
$92.10 150 $13,815
$62.33 150 $9,350
$38.33 1,440 $55,189
$16.67 1,440 $24,011
$20.53 1,060 $21,765
$213,533
Upper Random Fill
Resource Descr'lption Units CosUUnit Task Units Task Cost
Equipment Operators hrs $18.94 1,175 $22,258
Cat 637 Scraper hrs $205.10 470 $96,421
Cat 825 Compactor hrs $93.85 118 $11,030
Cat D8N Dozer With Ripper hrs $94.96 118 $11,161
Cat 07 Dozer hrs $80.38 118 $9,447
Cat 651 Waterwagon hrs $107.49 118 $12,633
Cat 14G Motorgrader hrs $70.59 118 $8,296
5000 Gallon Water Truck hrs $62.33 118 $7,326
Equipment Maintenance (Butler) hrs $20.53 1,175 $24,132
Total Place Upper Random Fill $202,704
Rock Armor and Filter Layer
Resource i Units CosUUnit Task Units Task Cost
i Operators Ihrs $18.94 72C ;13,636
Cat 07 Dozer I hrs 24C ;19,292
Cat 651 Waterwagon hrs $107.49 240 ;25,797
Cat 14G Motorgrader hrs $70.59 24C ;16,94'
Rock Cost Delivered ;y $5.7: 48 RQ'i
Equipment Maintenance (Butler) hrs 72C $14,784
Total Place Rock Armor and Filter Layer $371,260
Quality Control
Resource Description Units CosUUnit Task Units Task Cost
Quality Control Contractor 1 $62001 1,0451 $64,7901
Total Quality Control $64,790
TOTAL RECLAMATION OF CELL 4A $1,336,7541
WMM Rec Plan Est June 2010 Rev 3.2
Volume Route Yds! Hr % Eguie Hours
Cell 4 Bridging Lift
Tailings Surface 198,500 4 296 100% 670.6
Cell 4A Lower Random Fill
Tailings Surface 66,000 5 368 100% 179.3
South Slope 77,000 5 368 100% 209.2
East Slope 1,200 5 368 100% 3.3
391.8
Cell 4A Upper Random Fill
Tailings Surface 132,500 5 368 100% 360.1
South Slope 34,000 5 368 100% 92.4
East Slope 6,500 5 368 100% 17.7
470.1
Rock Armor
Rip Rap 42,675 100%
Filter 6,020 100%
WMM Rec Plan Est June 2010 Rev 3.2
Volume Calculation -Cell 4A
1) Area of Cell4A . 1,785,960 sq It ~ 41.00 acres
2) Assumptions
3)
4)
-Bridging layer is placed using random fill from piles east of Cell 4A
-Cell will be graded to Design elevation utilizing finer materials in random fill stockpiles
and from "clay" stockpiles.
-Clay will be mined, blended, and hauled from borrow site location in Section 16 -
four miles south of the mill area, using belly dump trucks, clay layer on top of Cell only.
-The upper 1 foot of random fill will be placed utilizing the fine random fill and clay stockpiles
-Rock for side armor, top armor and toe aprons will come from an off-site gravel source
one (1) mile north of Blanding. Rock will be produced through screening, stockpiled and
trucked to the site at the time of use. Belly dump trucks will dump gravel in windrows
on the top and sides of the Cell.
Bridging Layer ( Platform Fill) Remaining to be placed
1,785,960 sq ft X 3 ft. / 27 cubic feet per cubic yard ~ 198,440
Use I 198,500
Bring Platform Fill up to Design elevation (Lower Random)
Assume full area of Cell X one (1) foot thick
1,785,960 sq ft X 1 ft. / 27 cubic feet per cubic yard ~ 66,147
Use I 66,000
5) Placement of Clay Layer ( One (1) foot thick on top of Cell only)
Assume full area of Cell X one (1) foot thick
cubic yards
cubic yards
cubic yards
cubic yards
1,785,960 sq ft X 1 ft. / 27 cubic feet per cubic yard ~ 66,147 cubic yards
Use I 66,000 cubic yards
Volume Calculation Cell 4A Rev 4.2 June 2010
Volume Calculation -Cell4A (can't) page 2
6) Upper Random Fill Volume -Top of Cell area
Assume full area of Cell X one (2) foot thick
1,785,960 sq ft X 2 ft. / 27 cubic feet per cubic yard =
7) Armor Protection -Top of Cell
Assume full area of Cell X one-half (0.5) foot thick
132,293 cubic yards
Use I 132,500 cubic yards
1,785,960 sq ft X 0.5 ft. / 27 cubic feet per cubic yard = 33,073 cubic yards
8) Cell 4A South Dike, ( Slope #1 )
Average height
Length
36 feet
1600 feet
a) Random fill to reduce slope from 3:1 to 5:1
First Wedge [36 X 36 X 5)/2 -(36 X 36 X 3)/2J X 1600
= 2,073,600 cubic feeU 27 =
Remaining Random Fill
[39 X 39 X 5)/2 -(36 X 36 X 5)/2J X 1600
900,000 cubic feeU 27 =
Total Random Fill South Slope
b) Rock Armor 8" thick -0.67 feet
[39.67 X 39.67 X 5)/2 -(39 X 39 X 5)/2J X 1600
= 210,836 cubic feet! 27 =
Volume Calculation Cell4A Rev 4.2 June 2010
Use I 33,000 cubic yards
76,800 cubic yards
Use I 77,000 cubic yards
33,333 cubic yards
Use I 34,000 cubic yards
111,000 cubic yards
7,809 cubic yards
Usel~~7,_80_0~c~ub~ic~ya_rd~s~
Volume Calculation -Cell 4A (can't) page 3
c) Rip Rap Filter 6" thick -0.5 feet
[39.5 X 39.5 X 5)/2 -(39 X 39 X 5)/2J X 1600
157,000 cubic feet! 27 =
Use
5,815 cubic yards
6,000 cubic yards
d) Rock Apron at toe of slope [2ft X 7ft wide X 1600 10ngJ / 27 = 830
Total Rock Armor South Slope
9) Cell 4A East Slope (Slope #2 )
Average height
Length
8 feet
1200 feet
a) Random fill to reduce slope from 3:1 to 5:1
First Wedge [8 X 8 X 5)/2 -(8 X 8 X 3)/2J X 1200
76,800 cubic feet! 27 =
Remaining Random Fill
[11 X 11 X 5)/2 -(8X8X5)/2] X 1200
= 171,000 cubic feet! 27 =
Total Random Slope #3
Use~I __ ~8~5~0_c~u~b~ic~y~a~rd~s~
8,650 cubic yards
1185 cubic yards
Use~I __ ~1~,2~0~0~CU~b~ic~y~a~rd~s~
6,333 cubic yards
Use I 6,500 cubic yards
7,700 cubic yards
b) Rock Armor 8" thick -0.67 feet 14.52 cubic feet per linear foot of dike
14.52 cubic foot per linear foot X 1200 1 27
= 645 cubic feetl 27 = 24 cub',c yards
Usel~ ___ 2~5~c~u~bi~c~ya~r~ds~
c) Rip Rap Filter 6" thick -0.5 feet
10.84 cubic foot per linear foot X 1200 1 27
Volume Calculation Cell 4A Rev 4.2 June 2010
Volume Calculation -Cel14A (can't) page 4
=
c) Toe Apron Not required
482 cubic feet/ 27 =
Use
Total Rock Armor Cell 4A East Slope
Volume Summary -Cell 4A
Lower Upper
Bridging Layer Random Clay Random
Top of Cell 198,500 66,000 66,000 132,500
South ( Slope #1 ) 77,000 34,000
East (Slope #2 ) 1,200 6,500
Totals 198,500 144,200 66,000 173,000
Volume Calculation Cell 4A Rev 4.2 June 2010
18 cubic yards
20 cubic yards
25 cubic yards
Rock Rip Rap
Armor Filter
33,000 0
8,650 6,000
25 20
41,675 6,020
Volume Calculation -Cell4A (can't) page 5
Cell 4A Reclamation
Cat 637 Resource Requirements
Volume Route Yds/hr % Equip. Hr.
Cell 4A Bridging Lift
Tailings Surface 198,500 4 296 100% 670.6
Cell 4A Lower Random Fill
Tailings Surface 66,000 5 368 100% 179.3
Slope 1 77,000 5 368 100% 209.2
Slope 2 1,200 5 368 100% 3.3
Total 391.8
Cell 4A Upper Random Fill
Tailings Surface 132,500 5 368 100% 360.1
Slope 1 34,000 5 368 100% 92.4
Slope 2 6,500 5 368 100% 17.7
Total 470.1
Cell 4A Rock Armor --use Highway Trucks
Volume Calculation Cell 4A Rev 4.2 June 2010
Volume Calculation -Cell 4A (can't) page 6
Clay Volume =
=
Clay Production Cell 4A
( use same assumptions as Cell 2 )
66,000 Bank Cubic Yards (BCY)
0.8 Swell Factor
82,500 Loose Cubic Yards (LCY)
Trucking 475 LCY/hr 8 trucks plus one (1) Loader
85,000 LCY / 475 LCY/hr = 174 hours
use 180 hours
180 X 8 Trucks = 1,440 hours
Machine Hours
980 Loader 180
D8N w/ ripper 180
Cat 651 WW 180
Cat 825 Camp. 200
14G Patrol 200
5000 gal WW 150
Rock Armor and Filter Layer Production Cell 4A
47,695 cubic yards (cy)
38 cy per hour times 8 trucks
304 cy per hour delivered
Assume 25% extra time for spreading, loading and screen wait
304/ 1.25 243.2 cy per hour 196 Hours
Volume Calculation Cell 4A Rev 4.2 June 2010
RECLAMATION OF CELL 48
Dewatering of Cell 4B
Resource Description
Dewatering of Cell 4B
Total Dewatering of Cell 4B
Place Bridging (Platform) Lift
Resource Description
Cat 637 Scraper
Cat 637 Scraper Operators
Cat 825 Compactor
Cat 825 Compactor Operator
Cat D8N Dozer With Ripper
Cat D8N Dozer Operator
Cat D7 Dozer
Cat D7 Dozer Operator
Cat 651 Waterwagon
Cat 651 Waterwagon Operator
Cat 14G Motorgrader
Cat 14G Motorgrader Operator
Equipment Maintenance (Butler)
Total Place Bridging (Platform) Lift
Place Lower Random Fill
Resource Description
Equipment Operators
Cat 637 Scraper
Cat 825 Compactor
Cat D8N Dozer With Ripper
Cat D7 Dozer
Cat 651 Waterwagon
Cat 14G Motorgrader
Equipment Maintenance (Butler)
Total Place Lower Random Fill
WMM Rec Plan Est June 2010 Rev 3.2
Ihrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
Units CosUUnit Task Units Task Cost
1 $0481 62,400 1 $30,0001
$30,000
Units CosUUnit Task Units Task Cost
$205.10 671 $137,545
$17.72 671 $11,881
$93.85 168 $15,735
$13.09 168 $2,194
$94.96 168 $15,921
$13.09 168 $2,194
$80.38 168 $13,476
$13.09 168 $2,194
$107.49 168 $18,020
$16.67 168 $2,795
$70.59 168 $11,834
$18.91 168 $3,170
$20.53 2,850 $58,520
$295,481
Units CosUUnit Task Units Task Cost
$18.94 882 $16,698
$205.10 392 $80,370
$93.85 98 $9,194
$94.96 98 $9,303
$80.38 98 $7,874
$10749 98 $10,530
$70.59 98 $6,915
$20.53 882 $18,103
$158,986
Clay Layer
Resource Description
Equipment Operators
Cat 637 Scraper
Cat 825 Compactor
Cat D8N Dozer With Ripper
Cat 07 Dozer
Cat 651 Waterwagon
Cat 14G Motorgrader
Cat 980 Loader
5000 Gallon Water Truck
Highway Trucks
Truck Drivers
Equipment Maintenance (Butler)
Total Ptace Clay Layer
Upper Random Fill
Resource Description
Equipment Operators
Cat 637 Scraper
Cat 825 Compactor
Cat D8N Dozer With Ripper
Cat 07 Dozer
Cat 651 Waterwagon
Cat 14G Motorgrader
5000 Gallon Water Truck
Equipment Maintenance (Butler)
Total Place Upper Random Fill
Rock Armor and Filter Layer
Resource Description
Equipment Operators
Cat 07 Dozer
Cat 651 Waterwagon
Cat 14G Motorgrader
Rock Cost Delivered
Equipment Maintenance (Butler)
Units
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
Units
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
hrs
Units
hrs
hrs
hrs
hrs
CY
hrs
Total Place Rock Armor and Filter Layer
Quality Control
Resource Description Units
Quality Control Contractor Ihrs
Total Quality Control
TOTAL RECLAMATION OF CELL 48
WMM Rec Plan Est June 2010 Rev 3.2
Cost/Unit Task Units Task Cost
$18.94 1,060 $20,075
$205.10 0 $0
$93.85 200 $18,771
$94.96 180 $17,094
$80.38 0 $0
$107.49 180 $19,347
$70.59 200 $14,118
$92.10 150 $13,815
$62.33 150 $9,350
$38.33 1,440 $55,189
$16.67 1,440 $24,011
$20.53 1,060 $21,765
$213,533
Cost/Unit Task Units Task Cost
$18.94 1,199 $22,709
$205.10 480 $98,372
$93.85 120 $11,253
$94.96 120 $11,387
$80.38 120 $9,638
$107.49 120 $12,888
$70.59 120 $8,464
$62.33 120 $7,474
$20.53 1,199 $24,620
$206,805
Cost/Unit Task Units Task Cost
$18.94 600 $11,363
$80.38 200 $16,076
$107.49 200 $21,497
$70.59 200 $14,118
$5.77 48,695 $280,811
$20.53 600 $12,320
$356,185
Cost/Unit Task Units Task Cost
1 $6200 1 1,0451 $64,7901
$64,790
$1,325,7801
Volume Route Ydsl Hr % Equip Hours
Cell 4B Bridging Lift
Tailings Surface 198,500 4 296 100% 670.6
Cell 4B Lower Random Fill
Tailings Surface 66,000 5 368 100% 179.3
South Slope 77,000 5 368 100% 209.2
West Slope 1,200 5 368 100% 3.3
391.8
Cell 4B Upper Random Fill
Tailings Surface 136,000 5 368 100% 369.6
South Slope 34,000 5 368 100% 92.4
West Slope 6,500 5 368 100% 17.7
479.6
Rock Armor
Rip Rap 42,675 100%
Filter 6,020 100%
WMM Rec Plan Est June 2010 Rev 3.2
Volume Calculation -Cell 4B
IUpdated 06/16/10
1) Area of Cell 4B " 1,785,960 sq It ~ 41 acres
/
2) Assumptions
3)
4)
-Bridging layer is placed using random fill from piles west of Cell 4B
" Cell will be graded to Design elevation utilizing finer materials in random fill stockpiles
and from "clay" stockpiles.
-Clay will be mined, blended, and hauled from borrow site location in Section 16-
four miles south of the mill area, using belly dump trucks, clay layer on top of Cell only.
-The upper 1 foot of random fill will be placed utilizing the fine random fill and clay stockpiles
~ Rock for side armor, top armor and toe aprons will come from an off-site gravel source
one (1) mile north of Blanding. Rock will be produced through screening, stockpiled and
trucked to the site at the time of use. Belly dump trucks will dump gravel in windrows
on the top and sides of the Cell.
Bridging Layer ( Platform Fill) Remaining to be placed
1,785,960 sq It X 3 It. 1 27 cubic feet per cubic yard ~ 198,440
Use I 198,500
Bring Platform Fill up to Design elevation (Lower Random)
Assume full area of Cell X one (1) foot thick
1,785,960 sq ft X 1 ft. 1 27 cubic feet per cubic yard ~ 66,147
Use I 66,000
5) Placement of Clay Layer ( One (1) foot thick on top of Cell only)
Assume full area of Cell X one (1) foot thick
cubic yards
cubic yards
cubic yards
cubic yards
1,785,960 sq ft X 1ft. 1 27 cubic feet per cubic yard ~ 66,147 cubic yards
Use I 66,000 cubic yards
Volume Calculation -Cell 4B (can't) page 2
6) Upper Random Fill Volume -Top of Cell area
Assume full area of Cell X one (2) foot th',ck
1,785,960 sq ft X 2 ft. / 27 cubic feet per cubic yard =
7) Armor Protection -Top of Cell
Assume full area of Cell X one-half (0.5) foot thick
132,293 cubic yards
Use I 132,000 cubic yards
1,785,960 sq ft X 0.5 ft. / 27 cubic feet per cubic yard = 33,073 cubic yards
8) Cell4A South Dike, ( Slope #1 )
Average height
Length
36 feet
1600 feet
a) Random fill to reduce slope from 3:1 to 5:1
First Wedge [36 X 36 X 5)/2 -(36 X 36 X 3)/2] X 1600
= 2,073,600 cubic feetl 27 =
Remaining Random Fill
[39 X 39 X 5)/2 -(36 X 36 X 5)/2] X 1600
= 900,000 cubic feet! 27 =
Total Random Fill South Slope
b) Rock Armor 8" thick -0.67 feet
[39.67 X 39.67 X 5)/2 -(39 X 39 X 5)/2] X 1600
= 210,836 cubic feetl27 =
Use I 33,000 cubic yards
76,800 cubic yards
Use I 77,000 cubic yards
33,333 cubic yards
Use I 34,000 cubic yards
111,000 cubic yards
7,809 cubic yards
Use I 7,800 cubic yards
Volume Calculation -Cell4B (can't) page 3
c) Rip Rap Filler 6" thick -0.5 feet
[39.5 X 39.5 X 5)/2 -(39 X 39 X 5)/2] X 1600
157,000 cubic feet! 27 =
Use
5,815 cubic yards
6,000 cubic yards
d) Rock Apron at toe of slope [2ft X 7ft wide X 1600 long]/ 27 = 830
Total Rock Armor South Slope
9) Cell 4B West Slope (Slope #2 )
Average height
Length
8 feet
1200 feet
a) Random fill to reduce slope from 3:1 to 5:1
First Wedge [8 X 8 X 5)/2 -(8 X 8 X 3)/2] X 1200
76,800 cubic feet! 27 =
Remaining Random Fill
[11 X 11 X 5)/2 -(8 X 8 X 5)/2] X 1200
= 171,000 cubic feet! 27 =
Total Random Slope #3
use~I __ ~8_5~0_c~U~b~ic~y~a_rd~s~
8,650 cubic yards
1185 cubic yards
useLI __ ~1~,2~0~0~CU~b~ic~y~a~rd~s~
6,333 cubic yards
Use I 6,500 cubic yards
7,700 cubic yards
b) Rock Armor 8" thick -0.67 feet 14.52 cubic feet per linear foot of dike
14.52 cubic foot per linear foot X 1200/27
645 cubic feetl27 = 24 cubic yards
UseLI ____ ~2~5~Cu~b~ic~y~a~rd~s~
c) Rip Rap Filter 6" Ihick -0.5 feet
10.84 cubic fool per linear foot X 1200 / 27
Volume Calculation -Cell 48 (can't) page 4
=
c) Toe Apron Not required
482 cubic feetl 27 =
Use
Total Rock Armor Cell4B West Slope
Volume Summary -Cell 48
Lower Upper
Bridging Layer Random Clay Random
Top of Cell 198,500 66,000 66,000 132,000
South ( Slope #1 ) 77,000 34,000
West (Slope #3 ) 1,200 6,500
Totals 198,500 144,200 66,000 172,500
18 cubic yards
20 cubic yards
25 cubic yards
Rock Rip[ Rap
Armor Filter
33,000 0
8,650 6,000
25 20
41,675 6,020
Volume Calculation -Cell 4B (can't) page 5
Cell 4B Reclamation
Cat 637 Resource Requirements
Volume Route Yds/hr % Equip, Hr,
Cell 4B Bridging Lift
Tailings Surface 198,500 4 296 100% 670,6
Cell 4B Lower Random Fill
Tailings Surface 66,000 5 368 100% 179.3
Slope 1 77,000 5 368 100% 209,2
Slope 2 1,200 5 368 100% 3,3
Total 391,8
Cell 48 Upper Random Fill
Tailings Surface 132,000 5 368 100% 358,7
Slope 1 34,000 5 368 100% 92.4
Slope 2 6,500 5 368 100% 17,7
Total 468,8
Cell 4B Rock Armor --use Highway Trucks
Volume Calculation -Cell 4B (can't) page 6
Clay Volume =
Clay Production Cel14B
( use same assumptions as Cell 2 )
66,000 Bank Cubic Yards (BCY)
0.8 Swell Factor
82,500 Loose Cubic Yards (LCY)
Trucking 475 LCY/hr 8 trucks plus one (1) Loader
85,000 LCY / 475 LCY/hr = 174 hours
use 180 hours
180 X 8 Trucks = 1,440 hours
Machine Hours
980 Loader 180
D8N w/ ripper 180
Cat 651 WW 180
Cat 825 Camp. 200
14G Patrol 200
5000 gal WW 150
Rock Armor and Filter Layer Production Cell 4B
47,695 cubic yards (cy)
38 cy per hour times 8 trucks
304 cy per hour delivered
Assume 25% extra time for spreading, loading and screen wait
304/1.25 243.2 cy per hour 196 Hours