DRC-2008-002561 - 0901a06880aea7b8

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DENEOJ)/I
Denison mincs (USA) Corp.
105(l lnh $reet, Suitc 950
Dcnwr, CO 80265
USA
Tel : 303 62&7798
Far : 3(I3 38$4125
www.dcnisonmincs.com
frt. *r[
M!NES
December 1 1, 2008
VIA PDF AND FEDERAL EXPRESS
Mr. Dane L. Finerlrock
Execuiive Secretary
Utah Radiation Control Board
State of Utah Department ol Environmental Quality
168 North 1950 West
Salt Lake City, UT 84114-4850
Re: White Mesa Uranium Mill; Radioactive Material License No. UT19OO479 andGroundwater Quality Discharge Permit No. UGW37OOO4 - Amendment RequestsRelating to Freeboard Limit Calculations lor Tailings Cells
Dear Mr. Finerfrock:
Reference is made to the letter dated October 9, 2008 from Denison Mines (USA) Corp.("Denison") to the Executive Secretary pursuant to which Denison requesteci an'interihvariance from an existing condition of its State of Utah Radioactive Maierials License No.
UT1900479 (the ".Lice.nse") and ancillary documents relating to lreeboard limits lor Tailings Cells3 and 4A at the White Mesa uranium mill (the "Mill'), and to your conditional approv6l letterdated November 20, 2008.
ln your conditional a.pproval.letter, y.oy-applgved an interim variance establishing a temporaryfreeboard limit for tailings Cells 3 and 4A, subject to the following conditions:
. Denison will submit an application to amend the License with revised freeboard
calculation methods for Cell 3 and Cell 4A, on or before December 5, 2OOB (this date
was extended to December 1 1, 2008);. r|te application will include all needed corresponding revisions to the Cell 4A BATMonitoring, Operations and Maintenance Plan ("BAT Plan") and the White Mesa MillTailingq Ma.nag.e.ment_.System and Discharge Minimiz'ation Technology (DMT)
Monitoring Plan ("DMT Plan");. Th9 application will.clarify and fully describe the malhematical basis lor reducing pool
surface areas based on the future dry tons ol tailings projected to be processed; i.e., tneconversion of tonnage volume (three dimension-al) to surface arda consumed (two
dimensional); and. The application will submit the proposed freeboard calculations for Cell 3 and 44 usingthe current tailings output projection and poolareas as applicable.
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Denison hereby applies for an amendment to the License, and lor ancillary amendments to theMill's State of Utah Groundwaler Discharge Permit No. UGW370004 (the'1GWDP"), to the BAT
Plan and to the DMT Plan, as described below.
1. Background lnformation
The tailings.impoundment system al the Mill is comprised ol lour cells. Tailings Cell 1, which is
q1_evap_or3.tion p^ond with a surlace area ol 52.9 acres, was completed and put into use in June1981. Tailings Cell 2 was c_ompleted and put into use in May 1980, and is currently fult andcovered with interim cover. Tailings Cell 3 was completed and put into use in Septeniber 1982
and is currently active, although it is getting close to becoming full. Tailings Cell 4A, which has
a surface area ol 40 acres, was constructed and put into useln 1989 andwas used lor a shortperiod of time to receive tailings solulions until Mill operations ceased in 1g91, due to low
commodity prices. Cell 4A fell into disrepair after lhat time. All of the tailings solutions andresidual crystals were removed from the Cell in 2006. Cell 4A has since been ie-lined and was
authorized by the Executive Secretary lor re-use on September lT,20OB.
Freeboard limits for the tailings cells are set out in the License, the GWDP, the BAT Plan and
DMT Plan, as follows:
(a) License
License condition 10.3 prwides that lhe lreeboard limit lor Cell 1 shall be set annually in
accordance with the procedures set out in Appendix E of the previously approved NRC licehseapplication, including the January 10, 1990 Drainage Reporl. Thtise procedures set the
freeboard limit for Cell 1 al 5615.4 leet above mean sea level ("lmsl"). The freeboard limil iscurrently being set at that level, and there are no issues associated with that calculation. Thelicense condition also states that the freeboard limit for Cell 3 shall be recalculated annually in
accordance with theprocedugs_99t_in the October 13, 1999 revision to the Drainage Repbrt.As discussed in our October 9, 2008 letter to you, these procedures no longer makdsensb forCell 3, and an interim variance was granted by you, ai discussed abovd. The procedures
currently required by License conditioi 10.3 loi ialculating tne teeboaiO-iimit for'Cell 3 aredescribed in Section 2 below.
License condition 10.3 does not contain a lreeboard limit for Cell 2, since that cell is lull and
covered with interim cover, nor does it contain a freeboard limit for Cell 44. Previous versionsof License condition 10.3 did prescribe a freeboard limit calculation for Cell 44. However,reference to Cell 4A was taken out ol License condition 10.3 when Cell 4A was taken out oiservice and was not added back in when Cell 4A was recently authorized to be put back into
use.
-f..8..t_q.f,r"ry ]9, 1990 Drainage Report uses the Local 6-hour Probable Maximum Precipitation
ff-Uq") e.ve!t-.lgrcalculating the lreeboard requirement for each of the Mill's tailings celis. The
PMP for the Millsite is 10 inches. The January 10, 1990 Drainage Report establisled the PMPFlood Volume Requirement lo be handled in Cell 1 as 103 acreleet, in Cells 2 and O as 123.4acre feet, and lor Cell 44 as 36 acre feet. The freeboard limit for Cell 1 ol 5,615.4 fmsl has
been set to handle all of the PMP flood volume requirements associated with that cell. SinceCell 2 is full, all ol the volume requirement lor Cells 2 and 3 must be handled in Cell 3 or other
?cltyg tailings cells. The Drainage leport also established a wave run up factor for Cell 1 ol0.90 feet, Cell 3 ot O.79leet and for Cell 4A o10.77 leet.
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(b) GWDP
Parts 1.D.2 and 1.D.6(d) of the GWDP provide that under no circumslances shall the freeboard in
Cells 1 ,2,3 or 4A be less than three feet, as measured from the top ol the llexible membrane
liner ("FML").
(c) BAT Plan
The lreeboard calculations lor Cell 3 lor the period October 1, 2006 to September 30, 2007 and
for Cell 4Alor the period July 1, 2008 to June 30, 2009 are attached to the BAT Plan.
(d) DMT Plan
Section 6.3 ol the DMT Plan summarizes the steps to be taken to calculate the lreeboard limits
for Cell 3 as required under License condition 10.3 and sets oul the lreeboard limit calculation
for Cell 4A that was in eflect prior to the approvalof the interim variance discussed above.
For Cell 4A, the January 10, 1990 Drainage Report sets the flood volume from the PMP event
over the Cell 4A area at 36 acre feet, and the wave run up lactor at 0.77 feet. However,
because the Cell 4A design includes a concrete spillway between Cell 3 and Cell 4A, with the
invert elevation 4 leet below the top of the Cell 3 FML, should Cell 3 receive the lull PMP
volume ol 123.4 acre feet lor Cells 2 and 3, some of that volume would flow through the spillway
into Cell 4A. The volume that will flow over into Cell 44 will depend on the pool area in Cell 3
and can be calculated as the pool area in Cell 3 multiplied by 3.22 feet (i.e., the elevation
difference between the top of the FML in Cell 3 and the top of the spillway between Cell 3 and
Cell 4A of 4 feet, less the wave run up lactor of 0.78 feet). Based on the calculations for the
October 1, 2006 to September 30, 2007 period, this volume was calculated to be 61.6 acre leet.
This means that Cell 44 had to accommodate a total PMP volume of 97.6 acre feet (36 acre
feet from Cell 4A and 61.6 acre feet lrom Cell 3 overflow). Since Cell 4A has its total 4O-acre
area as a pool area, the total required lreeboard lor Cell 4A was calculated in the DMT Plan to
be 3.2 feet (i.e., the quotient of 97.6 acre feet divided by 40 acres, which equals 2.44 feet, plus
the wave run up lactor of 0.77 feet).
2. Current Manner ol Calculating Freeboard for Cell 3 Under the License
The procedures prescribed under License condition 10.3 require that the pool area in Cell 3 be
calculated at the beginning ol each annual period (historically, October 1 to September 30). An
adjustment is then made to reduce the pool area during the period as a result of the expected
deposit of tailings solids into the cellduring the period. The PMP Flood Volume Requirement of
123.4 acre leet is then divided by the reduced pool area in Cell 3 to determine the PMP
freeboard level for that cell. The wave run up factor ol 0.78leet is then added to determine the
total required lreeboard lor Cell 3.
Specifically, the procedure, as presented in the January 10, 1990 submittal to NRC, for re-
calculation ol the lreeboard limit is stated in the following excerpt lrom that submittal:
Procedure Freeboard Limits tor Cell 3
The following procedure is intended to be used to determine the maximum
operating pool level in Cell 3. This procedure is necessary because tailings sand
deposition occupies some of the volume required to hold a PMP event. A
summary of the procedure is as follows:
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1. From a suruey of the Cell, the pool surface area will be determined.2. From this area 17.3 acres will be subtracted. The wave run up
requirement is determined. The maximum operating pool level is
then calculated from the dike crest elevation minus the flood volume
requirements divided by the pool area minus the wave run up
requirements.
The basis of the procedure will now be discussed.
During the period of March 1988 through October 1989, 465,859 dry tons of
tailings were added to Cell 3. From topographic maps generated from aerial
photographs, . . . the pool surtace area of Cell 3 was reduced by 11.9 acres. Totaldry tons divided by change in pool area extent yields the number of tons required
to reduce pool size by one acre, or 39,146 dry tons per acre.
The maximum amount of tailings that could be discharged in a one-year time
pgriod is 2.,_000 dry tons per day for 365 days with 93% mill availability, or 678,900
dry tons. The maximum tonnage divided by the number of tons required to reducepool size by one acre yields the maximum expected pool area reduction, or 17.3acres. This number is then subtracted trom lhe pool surtace area determined by
suruey or topographic means, yielding the reduced pool area.
The flood volume requirements ary 123.4 acre-feet as per section fof the January
10,.1990 Drainage Reportl titledlCelll!fiypggfu!. The flood volume divided by the
reduced pool area is the freeboard required for the tlood. Wind-wave run-bp is
calculated as pg! th9 section [ot the January 10, 1990 Drainage Report] titled
Wave.Run-up. The PMP lreeboard requirement plus the wave run-up requiiementyield the total required freeboard.
Note that this procedure overestimates the required freeboard and therefore is a
conseruative method. The overestimation is a result of not taking credit for thevolume available for flood storage above the sand surtace. ln other words, this
method assumes that the sand at the edges of the pool rises vertically to the top otthe cell. The procedure also does not take credit for soil retention /osses
considered in the three cases used to develop the treeboard vs pool surface area
graph.
The following example is calculated using the above procedure. On October 22,
1989 the pool area in Cell3, determined by aerial photography was 46.2 acres-
46.2-17.3 = 28.9 acres
This is the area in which the storm volume must be stored. The storm volume was
determined to be 123.4 acre-feet.
123.4 acre-feet / 28.9 acres = 4.3 teet
4.3leet + 0.7 teet = 5.0 feet
5608.0 feet - 5.0 feet = 5603.0 feet msl
This procedure willbe used yearly if the milloperates on a continuous basis. lf the
mill is shut down, then this procedure will be used and a submittat made to the
NRC when 600,000 dry tons have been placed in Cell3.
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By a letter dated October 13, 1999 to the United States Nuclear Flegulatory Commission
("NRC"), Denison (then named lnternational Uranium (USA) Corporation) applied for a
modilication to this procedure to take into consideration periods when the Mill is not operating at
full capacity, as assumed in the foregoing procedure. Specifically, Denison requested that the
License be amended so thal, instead of automatically subtracting 17.3 acres lrom the pool area
at the beginning ol the period (which is based on the maximum possible production of 678,900
dry tons lor the upcoming year divided by a pool reduction lactor ol 39,146 dry tons per acre),
an estimate ol lhe next 12 months' mill throughput would be made. The estimate would be
multiplied by a lactor of safety of 150%, and the number ol acres lo be subtracted from the pool
area at the beginning ol the period would be this estimated throughput (multiplied by 1.5)
divided by the pool reduction factor o139,146 dry tons per acre.
The eflect ol the modification to the procedure was to more realistically account for the addition
of tailings sand in the year ahead, based on the actual operating projection lor the Mill. That
request for amendment was granted by NRC and lorms the current basis lor calculating
lreeboard lor Celi3 under License condition 10.3.
3. Problems with Existing Requirements
There are several problems with the existing requirements. First, as a tailings cell gets filled
with tailings solids, the pool area gets smaller, and, as a tailings cell gets closer to being filled to
its capacity with solids the lreeboard can be limited dramatically. However, in the case ol Cell 3,
where there is a spillway to Cell 4A, so long as enough lreeboard is retained in Cell 4A for the
PMP volume for all ol Cells 2, 3 and 44, there is no need to set a lreeboard limit for Cell 3. For
example, using the calculations for the period October 1, 2008 to September 30, 2009, based
on planned production at the Mill, the pool area in Cell 3 would be expected to decrease such
that the required freeboard limit in Cell 3 for the period would be more than 15 feet below the
FML, which presents an almost unworkable situation because ol the small pool area. This
places an unnecessarily restrictive freeboard limit on Cell 3 when there is ample room in Cell 4A
to allow for the entire PMP volume for all three cells.
Second, a freeboard calculation must be developed lor Cell 4A, and License condition 10.3
needs to be amended to include relerence to Cell 4A.
Third, the manner ol determining the reduction in pool area lor Cell 3 was developed specifically
for Cell 3 and does not apply to Cell 4A. Therefore, a new melhod for estimating the reduction
in pool area for Cell 4A must be developed and implemented.
4. Proposed Manner of Addressing the Existing Problems With the Freeboard
Calculations
The primary objective is to ensure that there is enough lreeboard in the tailings system as a
whole to capture the PMP event applicable to the tailings cells as a whole. This was calculated
in the 1990 Drainage Report as 123.4 acre feet for Cells 2 and 3 and 36 acre leet for Cell 4A,
for a total ol 159.4 acre feet for the three cells. The wave run up lactors lor Cells 3 and 4A were
also calculated in the 1990 Drainage Report to be 0.78 andO.77leet, respectively. There is no
reason to question these PMP event and wave run up numbers, so they are accepted here.
The PMP Flood Volume Requirement lor Cell 1 was also calculated in the 1990
Drainage Report as 103 acre feet, which will continue to be handled by setting the freeboard
limit lor Cell 1 at 5615.4 fmsl, and can be ignored for the remainder ol the analysis.
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Because there is a spillway between Cells 3 and 4A, there is no need for Cell 3 to be able to
accommodate all of the PMP event lor Cells 2 and 3 (123.4 acre feet) il adequate capacity is
available in Cell 4A to handle its own PMP requirements (36 acre feet) plus whatever amount of
the Cell 2 and 3 PMP requirements cannot be handled by Cell 3 alone.
As a result, Denison proposes the lollowing:
(a) the freeboard limit lor Cell 1 will continue to be set at 5,615.4 fmsl, which is the level
currently required by the application of License condition 10.3, and will allow Cetl 1 to
capture all ol the PMP volume associated with Cell 1;
(b) the freeboard limit lor Cell 2 will continue to be inapplicable, since Cell 2 is filled with
solids; all of the PMP volume associated with Cell 2 will continue to be attributed to
Cell 3 anct/or Cell44 (or any luture tailings cells);
(c) the freeboard limil lor Cell 3 will be inapplicable, since Cell 3 is close to being filled
with solids, and all ol the PMP flood volume associated with Cells 2 and 3 wil! be
attributed to Cell 44 (ancUor any fulure tailings cells); and
(d) the freeboard limit for Cell 44 will be set assuming that the total PMP volume for Cells2, 3 and 4A ol 159.4 acre leet will be accommodated in Cell 44. The manner ol
calculating the lreeboard limit for Cell 4A is discussed in detail in Section 5 below.
5. Manner ol Calculating Freeboard Limit lor Cetl 4A
5.1. General Discussion of Methodoloov
The procedure for calculating freeboard limits for Cell 4A is based on the premise that on
average, once the cell has received enough tailings solids to form a beach area, the pool
surface area of the cellwill be expected to decrease in direct proportion to the decrease in total
available space in the cell lor tailings solids storage.
lntuitively, this makes sense. Ultimately, the tailings cell can be filled to the top of its FML with
tailings solids before the cell is closed. ln that case, there will be no ability for the cell lo store
the PMP flood event, and another cell will be required for that purpose. On the other hand,
when there are no beaches, the total pool area is available to hold the PMP flood event, so it isjust a question ol setting the lreeboard limit (i.e., pool elevation) at a levelthat will allow the total
PMP flood event to be stored within the cell. A linear relationship between these two extremes
will modelthe average reduction in poolarea.
This is easy to visualize in the simple case where a tailings cell is a three-dimensional rectangle,
and where tailings solids are deposiled into the cell in perfectly rectangular vertical three-
dimensional blocks. A block of tailings that uses up 25"/" ol the available storage area lor solidswill displace exactly 25"/" ol the pool surface area. As a result, the pool suiiace will have to
decrease in elevation enough to allow for lhis reduction in pool area.
ln reality, tailings solids are not deposited into tailings cells in perfectly rectangular three-
dimensional vertical blocks. ln facl, the tailings solids will be more likely to be deposited, atleast initially, in a triangular or cone-like manner, that would result typically in less pool area
being displaced per ton ol tailings at the outset than in the case of the vertical blocks, as the
tailings solids spread a bit over the bottom ol the cell. As a result, at the outset, the assumedlinear reduction in pool area from the disposition ol tailings solids into the cell will overstate the
actual reduction in pool area. However, eventually, we know that this will have to change, andas the tailings cell becomes more lilled up, the percentage reduction in pool area -will be
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somewhat greater than the percentage reduction in solids storage space in the cell, as tailings
solids build up in the bottom of the pool area, thereby reducing the space available above those
solids lor the disposition ol lurther solids. However, the inilial overstatement ol the reduction in
pool area will oflset exactly the subsequent understatement ol the reduction in pool area. And,
since the pool area is being reduced by more than ls necessary at the outset, the cumulative
effect is that the pool area will always be reduced enough to allow lor the lull PMP tlood event to
be stored within the cell.
Figure 1 shows this relationship graphically. Figure 1 shows the simple case where half ol the
available solids storage area of the Cell is lilled with new tailings solids. lt can be seen that thepool surface area is reduced by half. The Figure also shows how the lreeboard limit (pool
surface elevation) is then reduced to allow lor the lull PMP llood event to still be stored within
the cell. lt can also be seen that this is conservative, because, to lhe extent that the tailings
solids beach slopes towards the pool, there is added PMP llood storage capacity on the sloping
beach area.
5.2. Solids Disposal Capacitv of Cell 44
As stated in Part 1.D.5(c) ol the GWDP, the lloor and inside slopes of Cell 44 encompass about
40 acres and have a maximum capacity of 1.6 million cubic yards ol tailings material storage (as
measured below the 3-foot lreeboard required under the GWDP). Because tailings solids will
ultimately fill the tailings cell up to the top ol the FML (assuming the PMP llood volume
attributed to the cell is handled by another tailings cell), an additional 193,600 cubic yards (40
acres times 4,840 yards per acre times 1 yard) of storage capacity must be added to the 1.6
million cubic yards referred to above, lor a total tailings capacity of 1,793,600 cubic yards. The
tailings solids have been determined to have a density ol 86.50 dry lbs per cubic foot ol tailings,or 2,335 lbs per cubic yard (see the Mill's May 2000, Tailings Capacity Evaluation, Section 1,
Base Tailings Capacity). As a result, the total amount of tailings solids capacity in Cell 4A is
2,094,000 dry tons.
5.3. Procedure for Calculation ol Freeboard Limit for Cell 44
Denison proposes that the freeboard limit lor Cell 4A be calculated as follows:
(a) When the Pool Surface Area is 40 Acres
When the pool surface area in Cell 4A is 40 acres (i.e., when there are no beaches), the
freeboard limit for Cell 4A will be 5,593.7 fmsl, which is 4.76 leet below the FML (being thequotient of 159.4 acre feet divided by 40 acres, which equals 3.99 feet, plus the wave ruh up
factor for Cell 4A of O.77feet, rounded to the nearest one-tenth ol a foot);
(b) When the Maximum Elevation of the Beach Area is 5,593 fmslor Less
When the maximum elevation of the beach area in Cell 4A is 5593 fmsl or less, then the
freeboard limit will be 5,593.7 fmsl, which is the same as in (a) above. This allows for the
situation where there may be beaches, but these beaches are at a lower elevation than the
freeboard limit eslablished in (a) above, and there is therelore ample freeboard above the
beaches to hold the maximum PMP volume. The maximum elevation ol the beach area will be
determined by monthly surveys performed by Mill personnel in accordance with the Mill's DMT
Plan, which will be revised to include this requirement (see Section 6.1 below).
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(c) When the Maximum Elevation of the Beach Area First Exceeds 5,593lmsl
When the maximum elevation ol the beach area in Cell 4A lirst exceeds 5,593 fmsl, then lhe
freeboard limit for the remainder ol the ensuing year (period t=0) (until the next November 11)
will be calculated when that elevation is first exceeded (the "lnitial Calculation Date"), as follows:
The total number of dry tons ol tailings that have historically been deposited into
Cell 4A prior to the lnitialCalculation Date ("T6") will be determined;
The expected number ol dry tons to be deposited into Cell 4A for the remainder ol
the ensuing year (up to the next November 1), based on production estimates lor
that period ("&*"), willbe determined;
Ao. will be grossed up by a safety factor of 150% to allow lor a potential
underestimation of the number ol tons that will be deposited in the cell during the
remainder of the ensuing year. This grossed up number can be referred to as the
"modeled tonnage" for the period;
The total design tailings solid storage capacity ol Cel! 4A will be accepted as
2,094,000 dry tons of tailings;
The available remaining space in Cell 4A for solids as at the lnitial Calculation
Date will be calculated as 2,094,000 dry tons minus To;
The reduction in the pool surface area for the remainder of the ensuing year will
be assumed to be directly proportional to the reduction in the available space in
Cell 4A for solids. That is, the reduced pool surlace area for period t=0 ('ilPAo"),
alter the reduction, will be calcutated to be:
(1 - (Ao'x 1.5) I (2,094,000 - To)) x 40 acres - RP&
vii) The required lreeboard for Cell 4A for the remainder ol the period t=0 can be
calculated in feet to be the wave run up lactor lor Cell 4A of 0.77 leel plus the
quotient ol 159.4 acre feet divided by the RPfu. The freeboard limit lor Cell 4A lor
the remainder of period t=0 would then be the elevation ol the FML for Cell 44 of
5598.5 fmsl less this required lreeboard amount, rounded to the nearest one-tenth
of a foot; andviii) The foregoing calculations will be performed at the lnitial Calculation Date and the
resulting freeboard limit will persist untilthe next November 1.
An example of this calculation is set out in Appendix A to this application.
(d) Annual Freeboard Calculation When the Maximum Elevation of the Beach Area
Exceeds 5,593 fmsl
On November 1 of each year (the'Annual Calculation Date"), the reduction in pool area lor the
ensuing year (referred to as period t) will be calculated by:
i) First, calculating the Adjusted Fleduced Pool Area lor the previous period (ARPAI.
r) to refle_ct actual tonnages deposited in Cell 4A lor the previous period (period t-1). The RPA,., used lor the previous period was based on expected tonn.ages forperiod t-1, grossed up by a safety factor. The ARPA.-1 is merely the RPA that
would have been used for period t-1 had the actual tonnages lor year t-l been
known at the outset of period t-'1 and had the RPA been calculated-based on lhe
' We are proposing that the freeboard calculation be revised as of each November l, rather than continue with the
calculation being performed as of each October l, because it is more likely that a better estimate of production for
the upcoming year will be available at the later date.
i)
ii)
iii)
iv)
v)
vi)
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ii)
actual tonnages for period t-1. This allows lhe freeboard calculations to be
corrected each year to take into account actual tonnages deposited in the cell as
ol the date of the calculation. The ARPAT-1 Gon be calculated using the following
lormula:
(1 - A-, / (2,094,000 -T,.,)) x ARPA,.z = ARPAT-I
Where:I At-r is the actual number ol dry tons of tailings solids deposited in Cell 4A
during period t-l;I Trr is the actual number ol dry tons ol tailings solids historically deposited
in Cell 4A prior to the beginning ol period t-1; and. ARPAI.2 is the Adjusted Reduced Pool Area for period t-2. lf period t-2
started at the lnitial Calculation Date, then ARPAI2 is 40 acres;
Once the ARPA,.1 lor the previous period (period t-1) has been calculated, the
RPA lor the subject period (period t) can be calculated as lollows:
(1 - (Ar. x 1.5) I (2,094,OO0 - T,)) x ARPAI-1 - RPAr
Where:. A* is the expected number ol dry tons ol tailings to be deposited into Cell
44 lor the ensuing year (period t), based on production estimates for the
year (as can be seen from the loregoing formula, this expected number is
grossed up by a safety factor of 1.5);. Tt is the actual number of dry tons ol tailings solids historically deposited
in Cell 4A prior to the beginning of period t; ando ARPAT-1 is the Adjusted Reduced Pool Area lor period t-1, which is the
pool surface area for the previous period (period t-1) that would have
applied during that period, had modeled lonnages (i.e., expected
tonnages grossed up by the 150% salety factor) equaled actual tonnages
for the period;
The required lreeboard lor period t can be calculated in leet to be the wave run up
lactor for Cell 44 of 0.77 leel plus the quotient ol 159.4 acre leet divided by the
FlPAt. The lreeboard limit lor Cell 4A lor period t would then be the elevation ol
the FML lor Cell 4A ol 5598.5 fmsl less this required freeboard amount, rounded
to the nearest one-tenth of a loot; and
The loregoing calculations will be perlormed
period t and the resulting freeboard limit
Calculation Date for period t+1.
at the Annual Calculation Date for
will persist until the next Annual
iii)
iv)
An example ol this calculation is set out in Appendix A to this application.
(e) When a Spillway is Added to Cell4A that Allows Overflow lnto a New Tailings Cell
When a spillway is added between Cell 4A and a new tailings cell (Cell 4B), then, if the
freeboard limit lor the new cell is set to cover the entire PMP event lor Cells 2,3, 4A and 48, the
freeboard limit for Cell 44 will be inapplicable.
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6. Amendments to BAT Plan and DMT Plan
6.1. Amendments to DMT Plan
Two sections of the Mill's DMT Plan require amendment in order to incorporate the amended
procedures lor calculating lreeboard limits proposed in Sections 4 and 5 above. These are
Sections 3.1 (d), entitled'Tailings Wastewater Pool Elevation Monitoring", and paragraphs (a),
(b) and (c) of Section 6.3, entitled "Freeboard Limits." ln addition, corresponding amendments
are required to the heading lor Section 3.1, to Section 8.2 and to the Weekly lnspection Form.
(a) Section 3.1 (d), Tailings Wastewater Pool Elevation Monitoring
Section 3.1 (d) ol the DMT Plan currently requires that weekly surveys of the solution elevations
in tailings Cells 1, 3 and 4A and Roberts Pond be made. This Section must be revised to:
. Eliminate the need lo survey solution elevations in Cell 3, because the freeboard limit
will no longer be applicable to that cell; and. Add the requiremenl to take monthly surveys ol the area of the Cell 4A beach with the
highest elevation.
(b) Freeboard Limits
Paragraphs (a), (b) and (c) ol Section 6.3 of the DMT Plan currently set out the methods for
calculating lreeboard limits lor tailings Cells 1, 3 and 4A. These paragraphs must be replaced
with the procedures outlined in Sections 4 and 5 above. Paragraph (d) of Section 6.3 currently
sets out the freeboard limit for Roberts Pond, which does not need lo be changed.
A copy of the DMT Plan marked to indicate these proposed amendments is attached as
Appendix B to this application.
6.2. Amendments to BAT Plan
Denison is proposing that two Sections of the BAT Plan be amended in connection with this
amendment request. These are the Sections entitled "Routine Maintenance and Monitoring:
Solution Elevations" and "Cell4A Solution Freeboard Calculation."
(a) Routine Maintenance and Monitoring: Solution Elevations
This Section ol the BAT Plan merely repeats the weekly solution elevation surveying
requirements of the DMT Plan. Denison proposes that this Section ol the BAT Plan be replaced
with the following paragraph that cross refers to the applicable requirements ol the DMT Plan:
Measurements ol pond solution elevations are to be taken on a weekly basis,
and the area ol the tailings beach with the highest elevation in Cell 4A is to be
taken on a monthly basis, by use ol the procedures and equipment specified in
Section 3.1 (d) ol the White Mesa Mill Tailings Management System and
Discharge Minimization Technology (DMT) Monitoring Plan.
This will eliminate the potential lor confusion and inconsistency that may result from the
application of similar provisions in two different compliance documents.
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(b) Cell4A Solution Freeboard Calculation
This Section ol the BAT Plan must be revised to reflect the revised lreeboard limit procedures
proposed by this application. The revised Section will provide a general description ol the
procedures, but will refer to the DMT Plan for the actual procedures. As mentioned above,
Denison believes that it is not desirable lo have the same or similar procedures repeated in
different documents. lt is also no longer necessary to attach a calculation ol the current
freeboard calculation lor Cells 3 and 4A to the BAT Plan, so Denison proposes that that
attachment to the BAT Plan be eliminated.
A copy of the BAT Plan marked to indicate these proposed amendments is attached as
Appendix C to this application.
7. Specilic Proposed Revisions to the Wording of License Gondition 10.3
License condition 10.3 currently reads as follows:
The Freeboard limit for Cell 1 shall be set annually in accordance with the
procedures set out in Section 3.0 to Appendix E ol the previously approved NRC
license application, including the January 10, 1990 Drainage Report. The
lreeboard limit lor Cell 3 shall be recalculated annually in accordance with the
procedures set in the October 13, 1999 revision to the Drainage Report. Said
calculations shall be submitted as part of the annual Technical Evaluation Report.
Said report shall be submitted lor Executive Secretary approval no later than
September 1, of each year.
Section 3.0 to Appendix E ol the previously approved NRC license application (i.e., the
1991/1997 license renewal application) referred to in License condition 10.3 was a section ol
the Mill's Environmental Protection Manual that was applicable at the time of that license
renewal. That Section of the Mill's Environmental Protection Manual is now Section 6.3 of the
DMT Plan, which is Section 3.1 ol the Mill's current Environmental Protection Manual.
As discussed in Section 6 above, all of the proposed procedures for calculating freeboard limits
lor the Mill's tailings, referred to in Sections 4 and 5 above, are set out in a revised Section 6.3
ol the Mill's DMT Plan. Therefore, Denison proposes that License condition 10.3 be revised to
read as follows:
The Freeboard limit for Cell 1 shall be 5615.4 leet above mean sea level, and the
freeboard limit for Cell 44 shall be set annually in accordance with the procedures
set out in Section 6.3 of the White Mesa Mill Tailings Management System and
Discharge Minimization Technology (DMT) Monitoring Plan, which is included as
Section 3.1 of the Mill's Environmental Protection Manual. Said calculations shall
be submitted as part of the annual Technical Evaluation Report. Said report shall
be submitted lor Executive Secretary approval no later than September 1, of each
year.
8. Ancillary Amendments to the Mill's Groundwater Discharge Permit
Part 1.D.2 ol the Mill's GWDP states that under no circumstances shall the freeboard for Cells 1,
2 and 3 be less than three leet, as measured from the top ol the FML. However, as discussed
above, tailings Cells 2 and 3 are lull or nearly lull and the lreeboard limits for those cells should
be inapplicable.
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As a result, Denison is also hereby requesting that Part 1.D.2 ol the Mill's GWDP be amended
by changing the third sentence ol that provision to read as follows:
"Under no circumstances shallthe freeboard for Cell 1 be less than three (3) feet,
as measured lrom the top ol the FML."
9. Freeboard calculations lor Upcoming Year
Based on the procedures outlined in Sections 4 and 5 above, the proposed lreeboard
calculations lor the Mill's tailings cells at this time are:
(a) Cell 1
The freeboard limit for Cell 1 will continue to be set at 5,615.4 fmsl.
(b) Cett2
The lreeboard limil lor Cell 2 will be inapplicable, as all of the PMP llood event associated with
Cell 2 will be attributed to Ce]] 4A.
(c) Cett3
The freeboard limit lor Cell 3 will be inapplicable, as all of the PMP llood event associated with
Cell 3 will be attributed to Cell 4A.
(d) Cett4A
The freeboard limit lor Cell 4A will be 5,593.7 fmsl, as the pool area in Cell 4A is currently at the
full 40 acres. !l at any time the maximum elevation of the beach area in Cell 4A exceeds 5,593
fmsl, then the freeboard limit will be revised as contemplated in Section 5.3(c) above.
The foregoing freeboard limits will persist until November 1, 2009.
As the Mill's tailings cells are already licensed for use, and are subject to existing freeboard
requirements under the License which are designed to ensure that the established maximum
PMP flood event is retained within the tailings system, and the proposed amendment merely
addresses the specific manner of calculating those freeboard requirements, Denison believes
that the requested amendment is not a "major amendment" within the meaning of UAC R313-
24-3. As a result, an environmental report as contemplated by that rule lor major amendments
is not necessary and is not contained in this application
lf you have any questions or require any lurther inlormation, please contact the undersigned.
Frydenlund
ident Regulatory Alfairs and Counsel
cc: Ron F. Hochstein
Harold R. Roberts
Steven D. Landau
David E. Turk
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Appendix A
Example ol Calculations
I
Assumptions and Factors:
o Total PMP volume to be stored in Cell4A - 159.4 acre leeto Wave runup factor lor Cell 4A - 0.77 feetI o Total capaiity ot Cell 4A - 2,094,000 dry tonsI o Elevation of FML of Cell 4A - 5,598.5|ms]o Maximum pool surface area of Cell 4A- 40 acresr " H[T1#,:,:ff]L:rfli::::::;::'iffi",,,,
arrs'lexceedssse3
o Expected and actual production is as set lorth in the lollowing table:I
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Time Period Expected
Tailings Solids
Dispositioninto Cell 4A
Determined atthe beginningof the period
(dry tons)'
Expecled
Tailings
Solids
Disposition
into Cell
4A at the
beginning
ol the
period,
multiplied
by 150o/o
Salety
Factor (dry
tons)
Actua! Tailings
Solids
Dispositioninto Cell 4A
determined atend of theperiod (dry
tons)*
March 1, 2009to November
1. 2009
I5U,UUU 225,000 z:z5,uuu
NovemDer 1,2009 to
November 1,
2010
3OU,OUU I5U,UOU 2t5,OOI)
November 1,2010 to
November 1,
2011
ZUU,UUU SUU,OUU Z5U,UUU
'These expected and actual tailings and production numbers and dates are lictional and
have been assumed for illustrative purposes only.
Based on these assumptions and factors, the lreeboard limits lor Cell 4A would be
calculated as follows:
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1. Prior to March 1. 2009
Prior to March 1, 2009, the maximum elevation of the beach area in Cell 4 is less than or
equal to 5,593|msl, therelore the freeboard limit is set at 5,593.7 fmsl.
2. March 1. 2009 to November 1. 2009
The pool surface area would be reduced to the lollowing amount
(1 - 225,000/ (2,094,000 - 1,000,000)) x 40 acres = 31.77 acres
Based on this reduced pool area, the amount ol lreeboard would be 159.4 acre leet divided by
31.77 acres equals 5.02 feet. When the wave run up laclor lor Cell 4A of 0.77 leel is added to
this, the total lreeboard reguired is 5.79 feet. This means that the freeboard limit lor Cell 4A
would be reduced from 5593.7|ms1 to 5592.7 fmsl (5598.5|msl minus 5.79leet, rounded to the
nearest one-tenth ol a foot). This calculation would be perlormed at March 1, 2009, and this
freeboard limit would persist until November 1, 2009.
3. November 1. 2009 to November 1. 2010
The pool surface area would be reduced to the following amount:
First, recalculate the pool surface area that should have applied during the previous
period, had modeled tonnages (i.e., expected tonnages grossed up by the 150% salety
factor) equaled actual tonnages for the period. Since the actual tonnage of 225,000 dry
tons was the same as the modeled tonnage of 225,000 dry tons, the recalculated pool
surface area is the same as the modeled pool surface area for the previous period,
which is 31.77 acres.
Then, calculate the modeled pool surface area to be used for the period:
(1 - 450,000 I (2,094,000 - 1,000,000 - 225,000)) x 31.77 acres = 15.32
acres
Based on this reduced pool area, the amount of freeboard would be 159.4 acre leet
divided by 15.32 acres equals '10.40 feet. When the wave run up factor for Cell 4A ol
O.77 leel is added to this, the total f reeboard required is 1 1 . 1 7 feet. This means that the
freeboard limit for Cell 44 would be reduced lrom 5592.7 fmsl to 5587.3 fmsl (5,598.5
fmsl minus 11.17 feet, rounded to the nearest one-tenth of a foot). This calculation
would be performed at November 1, 2009, and this lreeboard limit would persist until
November 1,2010.
4. November 1. 2010 to November 1. 2011
The pool surface area would be reduced to the lollowing amount:
First, recalculate the pool surface area that should have applied during the previous
period, had modeled tonnages (i.e., expected tonnages grossed up by the 150% salety
factor) equaled actual tonnages for the period. Since modeled tonnages exceeded
actual tonnages, the pool area was reduced too much during the previous period, and
must be adjusted. The recalculated pool area for the previous period is:
(1 - 275,0001 (2,094,000 - 1,000,000 - 225,000) x 31.77 acres = 21.72 acres.
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This recalculated pool surlace area will be used as the starting point lor the freeboard
calculation to be performed at November 1, 2010.
Then, calculate the modeled pool surface area to be used for the period:
(1 - 300,000 I (2,094,000 - 1,000,000 - 225,000 - 275,000\) x 21.72
acres = 10.75 acres
Based on this reduced pool area, the amount ol lreeboard would be 159.4 acre leet
divided by '10.75 acres equals 14.83 feet. When lhe wave run up lactor lor Cell 4A ol
O.77leel is added to this, the total freeboard required is 15.60 feet. This means that the
freeboard limit for Cell 4A would be reduced lrom 5587.3 fmsl to 5582.9 fmsl (5598.5
fmsl minus 15.60 leet, rounded to the nearest one-tenth ol a loot). This calculation
would be performed at November 1,2010, and this lreeboard limit would persist until
November 1, 2011.
15
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White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
9)2108 Revision: Denison€Z
Page I of45
APPENDIX B
WHITE MESA MILL TAILINGS MANAGEMENT SYSTEM
AND
DTSCHARGE MINTMLZLTION TECHNOLOGY (DMT)
MONITORING PLAN
1. INTRODUCTION
This Tailings Management System and Discharge Minimization Technology Monitoring Plan (the
"Plan") for the White Mesa Mill (the "Mill") provides procedures for monitoring of the tailings cell
system as required under State of Utah Radioactive Materials License No. UT1900479 (the
"Radioactive Materials License"), as well as procedures for operating and maintenance of monitoring
equipment and reporting procedures that are adequate to demonstrate DMT compliance under State
of Utah Ground Water Discharge Permit No. 370004 for the Mill (the "GWDP").
This Plan is designed as a systematic program for constant surveillance and documentation of the
integrity of the tailings impoundment system including dike stability, liner integrity, and transport
systems, as well as monitoring of water levels in Roberts Pond and feedstock storage areas at the
Mill. The Plan requires daily, weekly, quarterly, monthly and annual inspections and evaluations and
monthly reporting to Mill management.
2. DAILY TAILINGS INSPECTIONS
The following daily tailings inspections shall be performed:
2.1. Dail),ComprehensiveTailingslnspection
On a daily basis, including weekends, all areas connected with the four tailings cells will be
inspected. Observations will be made of the current condition of each cell, noting any corrective
action that needs to be taken.
The Environmental or Radiation Technician is responsible for performing the daily tailings
inspections, except on weekends when the Shift Foreman will perform the weekend tailings
inspections. The Radiation Safety Officer may designate other individuals with training, as
described in Section 2.4 below, to perform the daily tailings inspection.
Observations made by the inspector will be recorded on the Daily Inspection Data form(a copy of
which is attached in Appendix A). The Daily Inspection Dataformcontains an inspection checklist,
c)
d)
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White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
9)2108 Revision: Denison€Z
Page 2 of 45
which includes a tailings cells map, and spaces to record observations, especially those of immediate
concern and those requiring corrective action. The inspector will place a check by all inspection
items that appear to be operating properly. Those items where conditions of potential concem are
observed should be marked with an "X". A note should accompany the "X" specifying what the
concern is and what corrective measures will resolve the problem. This observation of concern
should be noted on the form until the problem has been remedied. The date that corrective action
was taken should be noted as well.
Areas to be inspected include the following: Cell 1,2,3, and 44, Dikes 1,2,3,4A-S, and 4A-w,
wind movement of tailings, effectiveness of dust minimization methods, spray evaporation , Cell2
spillway, Cell 3 spillway, Cell 3 and 4A liquid pools and associated liquid return equipment, cell
leak detection systems, and the wildlife ponds.
Operational features of the tailings area are checked for conditions of potential concern. The
following items require visual inspection during the daily tailings inspection:
a) Tailings slurry and SX raffinate transport systems from the Mill to the active
disposal cell(s), and pool return pipeline and pumps.
Daily inspections of the tailings lines are required to be performed when the Mill
is operating. The lines to be inspected include the: tailings slurry lines from CCD
to the active tailings cell; SX raffinate lines that can discharge into Cell l, Cell 3
or Cell 4,{; the pond return line from the tailings area to the Mill; and, lines
transporting pond solutions from one cell to another.
b) Cell 1.
Cell2.
Cell3.
Cell4,A.
Dike structures including dikes 1,2,3,4A-S, and 4A-W.
The Cell 2 spillway, Cell 3 spillway, Cell 3 and Cell 4,{ liquid pools and
associated liquid retum equipment.
Presence of wildlife and"/or domesticated animals in the tailings area, including
waterfowl and burrowing animal habitations.
Spray evaporation pumps and lines.
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White Mesa Mill - Srandard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
912108 Revision: Denison6T
Page 3 of45
j)Wind movement of tailings and dust minimization.
Wind movement of tailings will be evaluated for conditions which may require
initiation of preventative dust minimization measures forcells containing tailings
sand. During tailings inspection, general surface conditions will be evaluated for
the following: 1) areas of tailings subject to blowing and"/or wind movement, 2)
liquid pool size, 3) areas not subject to blowing and/or wind movement,
expressed as apercentage of the total cell area. The evaluations will be reviewed
on a weekly basis, or more frequently if warranted, and will be used to direct dust
minimization activities.
Observation of flow and operational status of the dust controUspray evaporation
system(s).
Observations of any abnormal variations in tailings pond elevations in Cells 1, 3,
and 4A.
Locations of slurry and SX discharge within the active cells. Slurry and SX
discharge points need to be indicated on the tailings cells map included in the
Daily Inspection Data form.
An estimate of flow for active tailings slurry and SX line(s).
An estimate of flow in the solution return line(s).
Daily measurements in the leak detection system (LDS) sumps of the tailings
cells will be made when warranted by changes in the solution level of the
respective leak detection system.
The trigger for further action when evaluating the measurements in the Cell 1 and
Cell 3 leak detection systems is a gain of more than 12 inches in 24 hours. The
solution level in Cell4,A, leak detection is not allowed to be more than 1.0 foot
above the lowest point on the bottom flexible membrane liner (elevation 5556.14
feet amsl). If any of these observation are made, the Mill Manager should be
notified immediately and the leak detection system pump started.
k)
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White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
912108 Revision: Denison€Z
Page 4 of 45
Whenever the leak detection system pump is operating and the flow meter
totalizer is recording, a notation of the date and the time will be recorded on the
Daily Inspection Data form. This data will be used in accordance with License
Condition 11.3.B through I 1.3.E of the Mill's Radioactive Materials License, to
determine whether or not the flow rate into the leak detection system is in excess
of the License Conditions.
q) An estimate of the percentage of the tailings beach surface iuea and solution pool
area is made, including estimates of solutions, cover areas, and tailings sands for
Cells 3 and 4,A..
Items (a), (m), (n), and (o) are to be done only when the Mill is operating. When the Mill is down,
these items cannot be performed.
2.2. Daily Operations lnspection
During Mill operation, the Shift Foreman, or other person with the training specified in Section 2.4
below, designated by the Radiation Safety Officer, will perform an inspection of the tailings line and
tailings area at least once per shift, paying close attention for potential leaks and to the discharges
from the pipelines. Observations by the lnspector will be recorded on the appropriate line on the
Operating Foreman's Daily Inspection form.
2.3. Daily Operations Patrol
In addition to the inspections described in Sections 2.1 and2.2 above, a Mill employee will patrol
the tailings area at least twice per shift during Mill operations to ensure that there are no obvious
safety or operational issues, such as leaking pipes or unusual wildlife activity or incidences.
No record of these patrols need be made, but the inspectors will notify the Radiation Safety Officer
and./or Mill management in the event that during their inspection they discover that an abnormal
condition or tailings emergency has occurred.
2.4. Training
All individuals performing inspections described in Sections 2.1 and2.2 above must have Tailings
Management System training as set out in the Tailings Inspection Training procedure, which is
attached as Appendix B. This training will include a training pack explaining the procedure for
performing the inspection and addressing inspection items to be observed. In addition, each
individual, after reviewing the training pack, will sign a certification form, indicating that training
has been received relative to hisftrer duties as an inspector.
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White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
9)2lOB Revision: Denison6Z
Page 5 of45
2.5. TailingsEmergencies
Inspectors will notify the Radiation Safety Officer and/or Mill management immediately if, during
their inspection, they discover that an abnormal condition exists or an event has occurred that could
cause a tailings emergency. Until relieved by the Environmental or Radiation Technician or
Radiation Safety Officer, inspectors will have the authority to direct resources during tailings
emergencies.
Any major catastrophic events or conditions pertaining to the tailings area should be reported
immediately to the Mill Manager or the Radiation Safety Officer, one of whom will notify Corporate
Management. If dam failure occurs, notify your supervisor and the Mill Manager immediately. The
Mill Manager will then notify Corporate Management, MSHA (303-231-5465), and the State of
Utah, Division of Dam Safety (801-538-7200).
3. WEEKLY TAILINGS AND DMT INSPECTION AND WEEKLY AND MONTHLY
SURVEYS
3.1. Weekly Tailings lnspections
Weekly tailings inspections are to be conducted by the Radiation Safety Department and include the
following:
a) Itak Detection Systems
Each tailings cell's leak detection system shall be checked weekly to determine
whether it is wet or dry. If marked wet, the liquid levels need to be measured and
reported. In Cell 1 and Cell 3 the leak detection system is measured by use of a
pipe that is removed from the system which will indicate the presence of
solutions in the LDS system. The Cell4,A. leak detection system is monitored on
a continuous basis by use of a pressure transducer that feeds water level
information to an electronic data collector. The pressure transducer is calibrated
for fluid with a specific gravity of 1.0. The water levels are measured every hour
and the information is stored for later retrieval. The water levels are measured to
the nearest 0. 10 inch. The data collector is currently programmed to store 7 days
of water level information. The number of days of stored data can be increased
beyond 7 days if needed. The water level data is downloaded to a laptop
computer on a weekly basis and incorporated into the Mill's environmental
monitoring data base, and into the files for weekly inspection reports of the
tailings cell leak detection systems
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White Mesa Mill - Standard Operating Procedures
Book I 1: Environmental Protection Manual, Section 3.1
912108 Revision: Denison6Z
Page 6 of45
If sufficient fluid is present in the leak detection system of any cell, the fluid shall
be pumped from the LDS, to the extent reasonably possible, and record the
volume of fluid recovered. Any fluid pumped from an LDA shall be returned to a
disposal cell.
If fluid is pumped from an LDS, the flow rate shall be calculated by dividing the
recorded volume of fluid recovered by the elapsed time since fluid was last
pumped or increases in the LDS fluid levels were recorded, whichever is the
more recent. This calculation shall be documented as part of the weekly
inspection.
Upon the initial pumping of fluid from an LDS, a fluid sample shall be collected
and analyzed in accordance with paragraph 11.3 C. of the Radioactive Materials
License.
For Cell 44, under no circumstance shall fluid head in the leak detection
system sump exceed a 1-foot level above the lowest point in the lower flexible
membrane liner. To determine the Maximum Allowable Daily LDS Flow
Rates in the Cell 4A leak detection system, the total volume of all fluids
pumped from the LDS on a weekly basis shall be recovered from the data
collector, and that information will be used to calculate an average volume
pumped per day. Under no circumstances shall the daily LDS flow volume
exceed 24,L60 gallons/day. The maximum daily LDS flow volume will be
compared against the measured cell solution levels detailed on Table 1 in
Appendix E, to determine the maximum daily allowable LDS flow volume for
varying head conditions in Cell 4A.
b) Slimes Drain Water Level Monitoring
(i) Cell 3 is an active tailings cell while Cell2 is partiallyreclaimed with approximately
9OVo of the surface covered by platform fill. Each cell has a slimes drain system
which aids in dewatering the slimes and sands placed in the cell;
(ii) Cell 2 has a pump placed inside of the slimes drain access pipe at the bottom of the
slimes drain. As taken from actual measurements, the bottom of the slimes drain is
38 feet below a water level measuring point at the centerline of the slimes drain
access pipe, at the ground surface level. This means that the bottom of the slimes
drain pool and the location of the pump are one foot above the lowest point of the
FML in Cell2, which, based on construction reports, is at a depth of 39 feet below
the water level measuring point on the slimes drain access pipe for Cell 2;
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I Wt it" Mesa Mill - Standard Operating Procedures
Book I l; Environmental Protection Manual, Section 3.1
912108 Revision: Denison6Z
PageT of45
(iii)The slimes drain pump in Cell 2 is on a timed system, under which it pumps for 15
minutes each hour, thereby allowing the slimes wastewater to recharge for 45
minutes before being pumped again. Based on measurements taken in August 2006,
the water level in the Cell 2 slimes drain recharges to a depth of about 28.50 feet
before each pumping and is pumped to a depth of 38 feet after each pumping, in each
case measured below the water level measuring point on the slimes drain access pipe.
The average wastewater head in the Cell2 slimes drain is therefore about 5 feet. The
depth to water of about 28.50 feet after recharge is below the phreatic surface of
tailings Cell 2, which is at a depth of about 20 feet below the water level measuring
point on the slimes drain access pipe. As a result, there is a continuous flow of
wastewater from Cell2 into the slimes drain collection system. Mill management
considers that the average allowable wastewater head in the Cell 2 slimes drain
resulting from pumping at these intervals is satisfactory and is as low as reasonably
achievable. Based on past experience, cycling the pump more than l5 minutes every
hour can result in more replacement costs for pumps and more resulting system
downtime;
(iv)The Cell2 slimes drain pump is checked weekly to observe that it is operating and
that the timer is set properly, which is noted on the Weekly Tailings Inspection Form.
If at any time the pump is observed to be not working properly, it will be fixed or
replaced within 15 days;
(v) Depth to wastewater in the Cell? slimes drain access pipe shall be monitored and
recorded weekly to determine maximum and minimum fluid head before and after a
pumping cycle, respectively. All head measurements must be made from the same
measuring point (the notch at the north side of the access pipe), and made to the
nearest 0.01 foot. The results will be recorded as depth-in-pipe measurements on the
Weekly Tailings Inspection Form;
(vi)On a monthly basis, the slimes drain pump will be turned off and the wastewater in
the slimes drain access pipe will be allowed to stabilize for at least 90 hours. Once
the water level has stabilized (based on no change in water level for three (3)
successive readings taken no less than one (1) hour apart) the water level of the
wastewater will be measured and recorded as a depth-in-pipe measurement on the
Monthly lnspection Data form, by measuring the depth to water below the water level
measuring point on the slimes drain access pipe;(vii) No process liquids shall be allowed to be discharged into Cell 2;(viii) If at any time the most recent average annual head in the Cell2 slimes drain is
found to have increased above the average head for the previous calendar year, the
Licensee will comply with the requirements of Part I.G.3 of the GWDP, including the
requirement to provide notification to the Executive Secretary orally within 24 hours
followed by written notification;
(ix)Because Cell 3 and Cell4A are currently active, no pumping from the Cell 3 or Cell
4A slimes drain is authorized. Prior to initiation of tailings dewatering operations for
Cell 3 or Cell 4A, a similar procedure will be developed for ensuring that average
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White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual. Section 3.1
9)2lOB Revision : Den ison67
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head elevations in the Cell3 and Cell44, slimes drains are kept as low as reasonably
achievable, and that the Cell 3 and Cell4A, slimes drains are inspected and the results
reported in accordance with the requirements of the permit."
c) Wind Movement of Tailings
An evaluation of wind movement of tailings or dusting and control measures
shall be taken if needed.
d) Tailings Wastewater Pool_and Beach Area_Elevation Monitoring
Solution elevation measurements in Cells 1r3 and 4,A, and Roberts Pond are to be taken by
survey on a weekly basis. and the beach area in
be taken by survey on a monthly basis. as follows:
(i) The survey will be performed by the Mill's Radiation Safety Officer or designee
(the "Surveyor") with the assistance of another Mill worker (the "Assistant");
(ii) The survey will be performed using a survey instrument (the "Survey Instrument")
accurate to 0.01 feet, such as a Sokkai No. 82l, or equivalent, together with a
survey rod (the "Survey Rod") having a visible scale in 0.01 foot increments;
(iii)The reference Points (the "Reference Points") for Cells 1# and 4.A, and Roberts
Pond are known points established by professional survey. For Cell I and Roberts
Pond, the Reference Point is a wooden stake with a metal disk on it located on the
southeast comer of Cell l. The elevation of the metal disk (the "Reference Point
Elevation") for Cell I and Roberts Pond is at 5,623.14 feet above mean sea level
("FMSL"). For Cell3+nd.eell4A, the Reference Point is a piece of metal rebar
located on the south dike of Cell 3. The elevation at the top of this piece of rebar
(the Reference Point Elevation for Cell3adell-4A) is at 5,607.83 FMSL;
(iv) The Surveyor will set up the Survey lnstrument in a location where both the
applicable Reference Point and pond or beach surface are visible. For Cell I and
Roberts Pond, this is typically on the road on the Cell I south dike between Cell I
and Roberts Pond, approximately 100 feet east of the Cell l/Roberts Pond
Reference Point. For Cell3+nd€ell-4A, this is typically on the road on the Cell 3
dike approximately 100 feet east of the Cell34l\ Reference Point;
(v) Once in location, the Surveyor will ensure that the Survey lnstrument is level by
centering the bubble in the level gauge on the Survey Instrument;
(vi)The Assistant will place the Survey Rod vertically on the Reference Point (on the
metal disk on the Cell l/Roberts Pond Reference Point and on the top of the rebar
on the Cell3+ndreell4A Reference Point. The Assistant will ensure that the
Survey Rod is vertical by gently rocking the rod back and forth until the Surveyor
has established a level reading;
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White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
9)2108 Revision: Denison{l
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(vii) The Surveyor will focus the cross hairs of the Survey lnstrument on the scale on
the Survey Rod, and record the number (the "Reference Point Reading"), which
represents the number of feet the Survey Instrument is reading above the
Rgeference Point;
(viii) The Assistant will then move to a designated location where the Survey Rod can
be placed on the surface of the main solution pond in theCell l. Cell 44 or
Roberts Pond. or the area of the beach in Cell 4A with the highest elevation. as the
case may be. These designated locations, and the methods to be used by the
Assistant to consistently use the same locations are as follows:
A. Pond Surface Measurements
I. Cell4,{
I€elB
Asiistant witt wa in+
B-€elH"a
The Assistant will walk down the slope in the northeast corner of Cell 44 and
place the Survey Rod at the liquid level.
il. Cell I
€*tL+
A mark has been painted on the north side of the ramp going to the pump
platform in Cell 1. The Assistant will place the Survey Rod against that mark
and hold the rod vertically, with one end just touching the liquid surface; and
Itr. Roberts Pond
D*ebe*s-Pend
A mark has been painted on the railing of the pump stand in Roberts Pond. The
Assistant will place the Survey Rod against that mark and hold the rod
vertically, with one end just touching the liquid surface.
Based on the foregoing methods, the approximate coordinate locations for the
measuring points for Roberts Pond and the Cells I and 4,\ pond surface are:
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White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
9)2108 Revision: Denison4T
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These coordinate locations may vary somewhat depending on solution
elevations in the Pond and Cells;
B. Cell4A Beach Elevation
The Assistant will olace the Survey Rod at the point on the beach area of Cell 44
that has the highest elevation. If it is not clear which area of the beach has the
highest elevation. then multiple points on the beach area will be survelred until the
Surveyor is satisfied that the point on the Cell 44 beach area with the highest
elevation has been surveyed. If it is clear that all points on the Cell 4,{ beach area
are below 5.593 FMSL. then the Surveyor may rely on one survey point:
(ix)The Assistant will hold the Survey Rod vertically with one end of the Survey Rod
just touching the pond or beach surface. The Assistant will ensure that the Survey
Rod is vertical by gently rocking the rod back and forth until the Surveyor has
established a level reading;
(x) The Surveyor will focus the cross hairs of the Survey Instrument on the scale on
the Survey Rod, and record the number (the "Pen*surface Reading"), which
represents the number of feet the Survey Instrument is reading above the pond or
beach surface level.
The Surveyor will calculate the elevation of the pond or beach surface as FSML by adding
the Reference Point Reading for the Cell or Roberts Pond, as the case may be, to the
Reference Point Elevation for the Cell or Roberts Pond and subtracting the Pen*surface
Reading for the Cell or Roberts Pond, and will record the number accurate to 0.01 feet.
e) Summary
In addition, the weekly inspection should summarize all activities conceming the
tailings area for that particular week.
Results of the weekly tailings inspection are recorded on the Weekly Tailings and DMT Inspection
form. An example of the Weekly Tailings and DMT Inspection form is provided in Appendix A.
3.2. Weekly Inspection of Solution lrvels in Roberts Pond
Northine Eastins
Roberts Pond 323,04r 2,579,697
Cell I 322,196 2.579,277H332s5e82+7'349
Cell4A 320,300 2,579,360
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On a weekly basis, solution elevations are taken on Roberts Pond, in accordance with the procedures
set out in Section 3.1 d) above. The Weekly solution level in Roberts Pond is recorded on the
Weekly Tailings and DMT Inspection form. Based on historical observations, the FML at the Pond
Surface Reading area for Roberts Pond, is approximately six inches above the lowest point on the
pond's FML. If the pond solution elevation at the Pond Surface Reading area is at or below the FML
for that area, the pond will be recorded as being dry.
3.3. Weekly Feedstock Storage Area Inspections
Weekly feedstock storage area inspections will be performed by the Radiation Safety Department, to
confirm that:
a) the bulk feedstock materials are stored and maintained within the defined area described in
the GWDP, as indicated on the map attached hereto as Appendix D; and
b) all alternate feedstock located outside the defined Feedstock Area are maintained within
water tight containers.
The results of this inspection will be recorded on the Ore Storage/Sample Plant Weekly Inspection
Report, a copy of which is contained in Appendix A. Any variance in stored materials from this
requirement or observed leaking alternate feedstock drums or other containers will be brought to the
attention of Mill Management and rectified within 15 days.
4. MONTHLY TAILINGS INSPECTION
Monthly tailings inspections will be performed by the Radiation Safety Officer or his designee from
the Radiation Safety Department and recorded on theMonthly Inspection Dataform, an example of
which is contained in Appendix A. Monthly inspections are to be performed no sooner than 14 days
since the last monthly tailings inspection and can be conducted concurrently with the quarterly
tailings inspection when applicable. The following items are to be inspected:
a) Tailings Slurry Pipeline
When the Mill is operating, the slury pipeline will be inspected at key locations to
determine pipe wear. Pipe thickness will be measured using an ultrasonic device by
either the radiation safety staff or other trained designees. The critical points of the
pipe include bends, slope changes, valves, and junctions, which are critical to dike
stability. These locations to be monitored will be determined by the Radiation Safety
Officer or his designee from the Radiation Safety Department during the Mill run.
b) Diversion Ditches
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Diversion ditches l, 2 and 3 shall be monitored monthly for sloughing, erosion,
undesirable vegetation, and obstruction of flow. Diversion berm2should be checked
for stability and signs of distress.
c) Sedimentation Pond
Activities around the Mill and facilities area sedimentation pond shall be summarized
for the month.
d) Overspray Dust Minimization
The inspection shall include an evaluation of overspray minimization, if applicable.
This entails ensuring that the overspray system is functioning properly. In the event
that overspray is carried more than 50 feet from the cell, the overspray system should
be immediately shut-off.
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e) Remarlcs
A section is included on the Monthly Inspection Data form for remarks in which
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recommendations can be made or observations of concern can be documented.
f) Summary of Daily, Weekly and Quarterly Inspections
I The monthly inspection will also summarize the daily, weekly and, if applicable,
quarterly tailings inspections for the specific month.
I In addition, settlement monitors are typically surveyed monthly and the results reported on the
Monthly Inspection Data form.
I 5. QUARTERLY TAILINGS IN'PECTI.N
I The quarterly tailings inspection is performed by the Radiation Safety Officer or his designee fromI the Radiation Safety Department, having the training specified in Section 2.4 above, once per
calendar quarter. A quarterly inspection should be performed no sooner than 45 days since the
I
previous quarterly inspection was performed.
Each quarterly inspection shall include an Embankment Inspection, an Operations/lVlaintenance
I Review, a Construction Review and a Summary, as follows:
I
a) Embankment Inspection
The Embankment inspection involves a visual inspection of the crest, slope and toe
I :ff::i:::: i,T#"*ment,
seepase' severe erosion, subsidence, shrinkage cracks,
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b) Operations/Maintenance Review
The Operations/Nlaintenance Review consists of reviewing Operations and
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Maintenance activities pertaining to the tailings area on a quarterly basis.
c) Construction Review
I The Construction Review consists of reviewing any construction changes or
modifications made to the tailings area on a quarterly basis.I
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Book I l: Environmental Protection Manual, Section 3.1
9)2log Revision: Denison4Z
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d) Summary
The summary will include all major activities or observations noted around the
tailings area on a quarterly basis.
If any of these conditions are noted, the conditions and corrective measures taken should be
documented in the Quarterly Inspection Data form. An example of the Quarterly Inspection Data
form is provided in Appendix A.
6. ANNUAL EVALUATIONS
The following annual evaluations shall be performed:
6.1. Annual Technical Evaluation
An annual technical evaluation of the tailings management system is performed 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 Section
5.2 below).
All tailings cells and corresponding dikes will be inspected for signs of erosion, subsidence,
shrinkage, and seepage. The drainage ditches will be inspected to evaluate surface water control
structures.
In the event tailings capacity evaluations (as per SOP PBL-3) 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.
Tailings inspection records will consist of daily, weekly, monthly, and quarterly tailings inspections.
These inspection records will be 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
Radiation Safety Officer regarding activities around the tailings area for the past year. During the
annual inspection, photographs of the tailings area will be taken. The training of individuals will be
reviewed as a part of the Annual Technical Evaluation.
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White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
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The registered engineer will obtain copies of selected tailings inspections, along with the monthly
and quarterly summaries of observations of concern and the corrective actions taken. These copies
will then be included in the Annual Technical Evaluation Report.
The Annual Technical Evaluation Report must be submitted by September I't of every year to:
Directing Dam Safety Engineer
State of Utah, Natural Resources
1636 West North Temple, Suite 220
Salt Lake City, Utah 84116-3156
6.2. Movement Monitors
A movement monitor survey is to be conducted by a licensed surveyor annually during the second
quarter of each year. 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
from this survey is reviewed and incorporated into the Annual Technical Evaluation Report of the
tailings management system.
6.3. Freeboard Limits
The freeboard limits set out in this Section are intended to capture the Local 6-hour Probable
Maximum Precipitation (PMP) event. which was determined in the January 10. 1990 Drainage
Report (the "Drainage Report") for the White Mesa site to be l0 inches.
The flood volume from the PMP event over the Cell I pond area plus the adjacent drainage areas.
was calculated in the Drainage Report to be 103 acre feet of water. with a wave run up factor of
0.90 feet.
The flood volume from the PMP event over the Cell 2 and Cell 3 pond areas. plus the adjacent
drainage areas was calculated in the Drainage Report to be 123.4 acre-feet of water.
The flood volume from the PMP event over the Cell 4A area was calculated in the Drainage
Report to be 36 acre-feet of water (40 acres. plus the adjacent drainage area of 3.25 acres. times
the PMP of l0 inches). with a wave run up factor of 0.77 feet.
The total pool surface area in Cell I is 52.9 acres and in Cell4A is 40 acres. The top of the
flexible membrane liner ("FML") for Cell I is 5.618.2 FMSL and for Cell44 is 5.598.5 FMSL.
Based on the foregoine. the freeboard limits for the Mill's tailings cells will be set as follows:
6.3.1. Cell I
I Wtrite Mesa Mill- Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
9l2l08 Revision: Denison4Z
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The freeboard limit for Cell 1 will be set at 5.615.4 FMSL. This will allow Cell I to capture all of
the PMP volume associated with Cell 1. The total volume requirement for Cell I is 103 acre feet
divided by 52.9 acres equals 1.95 feet. plus the wave run up factor of 0.90 feet equals 2.85 feet. The
freeboard limit is then 5.618.2 FMSL minus 2.85 feet equals 5.615.4 FMSL. Under Radioactive
Materials License condition 10.3. this freeboard limit is set and is not recalculated annually.
6.3.2. Cell2
The freeboard limit for Cell 2 is inapplicable. since Cell 2 is filled with solids. All of the PMP
volume associated with Cell 2 will be attributed to Cell 4A (and/or any future tailings cells).
6.3.3. Cell3
The freeboard limit for Cell 3 is inapplicable. since Cell 3 is close to being filled with solids. and all
of the PMP flood volume associated with Cell 3 will be attributed to Cell 4A (and/or any future
tailings cells).
6.3.4. Cell4A
The freeboard limit for Cell4.{ will be set assuming that the total PMP volume for Cells 2. 3 and 4A
of 159.4 acre feet will be accommodated in Cell 4A. The procedure for calculating the freeboard
limit for Cell4A is as follows:
(a) Wen the Pool Sufface Area is 40 Acres
When the pool surface area in Cell 4A is 40 acres (i.e.. when there are no beaches). the freeboard
limit for Cell4,A will be 5.593.7 FMSL. which is 4.76 feet below the FML (being the quotient of
159.4 acre feet divided by 40 acres. which equals 3.99 feet. plus the wave run up factor for Cell 4,{
of 0.77 feet. rounded to the nearest one-tenth of a foot):
(b) When the Maximum Elevation o.f the Beach Area is 5.593 FMSL or Less
When the maximum elevation of the beach area in Cell 4,A, is 5593 FMSL or less. then the freeboard
limit will be 5.593.7 FMSL. which is the same as in (a) above. This allows for the situation where
there may be beaches. but these beaches are at a lower elevation than the freeboard limit established
in (a) above. and there is therefore ample freeboard above the beaches to hold the maximum PMPvolume. The maximum elevation of the beach area will be determined by monthly surveys
performed by Mill personnel in accordance with the Mill's DMT Plan. which will be revised to
include this requirement (see Section 6.1 below).
(c) When the Maximum Elevation o.f the Beach Area First Exceeds 5.593 FMSL
When the maximum elevation of the beach area in Cell 4A first exceeds 5.593 FMSL. then the
freeboard limit for the remainder of the ensuins year (period t=0) (until the next November 1) will be
calculated when that elevation is first exceeded (the "Initial Calculation Date"). as follows:
White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.I
912108 Revision: Denison6T
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i) The total number of dry tons of tailings that have historically been deposited into Cell
4A prior to the Initial Calculation Date ("T0") will be determined:
ii) The expected number of dry tons to be deposited into Cell 4A for the remainder of the
ensuing year (uo to the next November l). based on production estimates for that
Period ("Anx"). will b. d.,. 'n.O'
iii) As*_will be grossed up by a safety factor of 150% to allow for a potential
underestimation of the number of tons that will be deposited in the cell during the
remainder of the ensuing year. This grossed up number can be referred to as the
"modeled tonnage" for the period:iv) The total design tailings solid storage capacity of Cell 4A will be accepted as
2.094.000 dry tons of tailines:v) The available remaining space in Cell4.A' for solids as at the Initial Calculation Date
will be calculated as 2.094.000 dry tons minus To:vi) The reduction in the pool surface area for the remainder of the ensuing year will be
assumed to be directly proportional to the reduction in the available space in Cell4,A,
for solids. That is. the reduced pool surface area for period t=0 ("RPAo"). after the
reduction. will be calculated to be:
(l - (Ast"x 1.5) / (2.094.000 - Ts)) x 40 acres = RPAo
vii) The required freeboard for Cell 4A for the remainder of the period t=0 can be
calculated in feet to be the wave run uLfactor for Cell 4,A, of 0.77 feet plus the
Erotient of 159.4 acre feet divided by the RPAg. The freeboard limit for Cell 4,A' for
the remainder of period t=0 would then be the elevation of the FML for Cell 4,{ of
5598.5 FMSL less this required freeboard amount. rounded to the nearest one-tenth of
a foot: andviii) The foregoing calculations will be performed at the Initial Calculation Date and the
resulting freeboard limit will persist until the next November l.
An example of this calculation is set out in Aopendix F.
( dl Annual Freeboard Calculation When the Maximum Elevation o.f the Beach Area Exceeds
5,593 FMSL
On November I of each year (the "Annual Calculation Date"). the reduction in pool area for the
ensuing year (referred to as period t) will be calculated by:
i) First. calculating the Adjusted Reduced Pool Area for the previous period (ARPArr)
to reflect actual tonnages deposited in Cell44. for the previous period (period t-l).
The RPAu used for the previous period was based on expected tonnages for period t-
l. grossed uo b), a safety factor. The ARPAd is merely the RPA that would have
been used for period t- I had the actual tonnages for year t- I been known at the outset
of period t-l and had the RPA been calculated based on the actual tonnaees forperiod
t-1. This allows the freeboard calculations to be corrected each year to take into
account actual tonnages deposited in the cell as of the date of the calculation. The
ARPA[can be calculated using the followins formula:
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Book I l: Environmental Protection Manual, Section 3.1
9)2108 Revision: Denison6Z
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(1 - Au / (2.094.000 - Tu)) x ARPATz= ARPA'T
Where:. Ar-r ls the actual number
during period t-l:o Trlis the actual number of dry tons of tailings solids historically deposited in
Cell 4,{ prior to the beeinning of period t- l: and. ARPA,-z rs the Adjusted Redu
started at the Initial Calculation Date. then ARPA"z is 40 acres:
ii) Once the ARPAu_for the previous period (oeriod t-1) has been calculated. the RPA
for the subject period (period t) can be calculated as follows:
(1 - (Ar* x 1.5) / (2.094.000 - TJ) x ARPAr.r- = RPA
Where:o A,x is the expected number of dry tons of tailines to be deposited into Cell 4A
for the ensuing year (period t). based on production estimates for the year (as
can be seen from the foregoing formula. this expected number is grossed up
bv a safetv factor of 1.5):o Tris the actual number of dry tons of tailings solids historicall), deoosited in
Cell 4,A, prior to the beginning of period t: ando ARPAr:_is the Adjusted Reduced Pool Area forperiod rl. which is the pool
surface area for the previous period (oeriod t-l) that should have applied
during that period. had modeled tonnages (i.e.. expected tonnages grossed up
by the 1507o safety factor) equaled actual tonnages for the period:
iii) The required freeboard for period t can be calculated in feet to be the wave run up
factor for Cell 4.A of 0.77 feet plus the quotient of 159.4 acre feet divided by the
RPA,. The freeboard limit for Cell 4,A, for period t would then be the elevation of the
FML for Cell4A of 5598.5 FMSL less this required freeboard amount. rounded to the
nearest one-tenth of a foot: andiv) The foregoing calculations will be performed at the Annual Calculation Date for
period t and the resulting freeboard limit will persist until the next Annual Calculation
Date for period t+1.
An examole of this calculation is set out in Appendix F.
(el Wen a Spillway is Added to Cell4A that Allows Overflow Into a New Tailinss Cell
When a spillway is added between Cell 44, and a new tailings cell (Cell 4B). then. if the freeboard
limit for the new cell is set to cover the entire PMP event for Cells 2. 3.4A and 48. the freeboard
limit for Cell 4,A. will be inapplicable.
6.3.5. Roberts Pond
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Book I l: Environmental Protection Manual, Section 3.1
912108 Revision: Denison6Z
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f*XeeUewehn:g/6 xe ?Eper lan ry
Tl'e freebeard limit fer eell 3 is determined annuallyusing the rlewing preeedure:
This estimate is multiplied by l=5; a faeter ef safety; te yield the Ma*imum Mill Preduetien,
A#ee
in+e*
velume weuld flew threugh the spillway irte €elt l,L
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Book I 1: Environmental Protection Manual, Section 3.I
9)2108 Revision: Denison4Z
Page 20 of 45
the a4iaeent drainage area ef 3,25 aereq times the PMP ef le inehes), This weuld result in a tetd
ioftis
White Mesa Mill requiresthat the nilnimum freebeard be ne less than3=O feet fer any ef the existing
tep ef liner. The freebeard fer €ell lA rveuld therefere be 5595.3 arnsl (tep ef liner 5598'5 3,2
H)=
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9)2108 Revision: Denison6Z
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ilXeW**
The freeboard limit for Roberts Pond is a liquid mzximum elevation of 5,624.0 feet above mean sea
level, as specified in the GWDP.
6.4. Annual [rak Detection Fluid Samples
ln the event solution has been detected in a leak detection system, a sample will be collected on an
annual basis. This sample will be analyzed according to the conditions set forth in License
Condition 11.3.C. The results of the analysis will be reviewed to determine the origin of the
solution.
7. OTHER INSPECTIONS
All daily, weekly, monthly, quarterly and annual inspections and evaluations should be performed as
specified in Sections 2,3,4,5 and 6 above. However, additional inspections should be conducted
after any significant storm or significant natural or man-made event occurs.
8. REPORTING REQUIREMENTS
ln addition to the Daily Inspection Data,Weekly Tailings Inspection, Monthly Inspection Data and
Quarterly Inspection Dataforms included as Appendix A and described in Sections 2,3,4 and 5
respectively, and the Operating Foreman's Daily Inspection and Weekly Mill Inspecrion forms
described in Sections 2 and3, respectively, the following additional reports shall also be prepared:
8.1. Monthly Tailings Reports
Monthly tailings reports are prepared every month and summarize the previous month's activities
around the tailings area. If not prepared by the Radiation Safety Officer, the report shall be
submitted to the Radiation Safety Officer for review. The Mill Manager will review the report as
well before the report is filed in the Mill Central File. The report will contain a summary of
observations of concern noted on the daily and weekly tailings inspections. Corrective measures
taken during the month will be documented along with the observations where appropriate. All daily
and weekly tailings inspection forms will be attached to the report. A monthly inspection form will
also be attached. Quarterly inspection forms will accompany the report when applicable. The report
will be signed and dated by the preparer in addition to the Radiation Safety Officer and the Mill
Manager.
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White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
9)2108 Revision : Denison6Z
Page 22 of 45
8.2. DMT Reports
Quarterly reports of DMT monitoring activities of all required information required by Part 1.F.2 of
the GWDP relating to the inspections described in Section 3.1(b) (Slimes Drain Water lrvel
Monitoring), 3.1(d) (Tailings Wastewater Pool and Beach Area Elevation Monitoring),3.2 (Weekly
Inspection of Solution lrvels in Roberts Pond) and 3.3 (Weekly Feedstock Storage Area Inspections)
will be provided to the Executive Secretary on the schedule provided in Table 5 of the GWDP. An
annual summary and graph for each calendar year of the depth to wastewater in the Cell2 slimes
drain must be included in the fourth quarter report. After the first year, and beginning in 2008,
quarterly reports shall include both the current year monthly values and a graphic comparison to the
previous year.
I
I I Wlite Mesa Mill - Standard Operating Procedures g)2t[SRevision: Denison6ZI Book I l: Environmental Protection Manual, Section 3.1 Page 23 of 45
APPENDIX A
FORMS
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White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
912108 Revision: Denison62
Page 28 of45
APPENDTX A (CONT)
DENTSON MrNES (USA) CORP.
WEEKLY TAILINGS INSPECTION
Date:lnspectors:
l. Pond and Beach Cell l: (a) Pond Solution Elevation
elevations (msl,ft)
(b) FML Bottom Elevation
(c) Depth of Water above FML ((a)-(b))
5597
(b)Flt4r Bettern Elevatien 5570
(e)nepth ef Water abeve FMt ((a) (b))
Cell 4,A': (a)Pond Solution Elevation
(b)FML Bottom Elevation 5564
(c)Depth of Water above FML ((a)-(b))
(d)Elevation of Beach Area
with Hishest elevation (monthlv)
Roberts
Pond: (a)Pond Solution Elevation
(b)FML Bottom Elevation _5612.34-
(c)Depth of Water above FML ((a)-(b)) _
2. Slimes Drain Liquid Levels Cell2 Pump functioning properly
Pump Timer set at l5min on 45 min off
Depth to Liquid pre-pump
Deoth to Liouid Post-oumo
(all measurements are depth-in-pipe)
Pre-pump head is 38'-Depth to Liquid Pre-pump =
Post-pump head is 38' -Depth to Liquid Post-
DumD =
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I Wtrite Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
912108 Revision: Denison6Z
Page29 of 45
White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
3. Leak Detection Systems
4. Tailings Area Inspection (Note dispersal of blowing tailings):
9J2lO8 Revision: Denison4Z
Page 30 of 45
Observation:
Cell I Cell2 Cell3 Cell4A
Is LDS wet or drv?wet dry wet drv wet drv wet drv
If wet, Record
liouid level:
_Ft to
Liouid
Ft to
Liouid
_Ft to
Liouid
Ft to
Liquid *
If sufficient fluid is
present, record
volume of fluid
pumped and flow
rate:
Volume
Flow Rate_
Volume
Flow Rate_
Volume
Flow Rate
Volume
Flow Rate_
Was fluid sample
collected?
ves no ves no ves no ves no
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5. Control Methods lmplemented:
6. Remarks:
7. Contaminated Waste Dump:
* Does Level exceed l2 inches above the lowest point on the bottom flexible membrane liner (elevation
5556.14 amsl)? _ no _ yes
If Cell 4A leak detection system level exceeds l2 inches above the lowest point on the bottom flexible
membrane liner (elevation 5556.14 amsl), notify supervisor or Mill manager immediately.
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I I Wnite Mesa Mill - Standard Operating ProceduresI Book I l: Environmental Protection Manual, Section 3.1
I
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APPENDTX A (CONT.)
MONTHLY INSPECTION DATA
912108 Revision: Denison6Z
Page 3l of45
Inspector:
I Date:
I 1. slurry Pipeline:
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I ;T:::;;;::,'"",;":':'onrvduringperiodswhentheM,risoperating)
I observation:I Diversion Ditch I Diversion Ditch 2 Diversion Ditch 3 Diversion Berm 2
Diversion Ditches:
I Sloughing yes-no
-yes-no -yes
noI Erosion _yes_no _yes_no yes_no
Undesirable _yes_no _yes_no _yes_noI Vesetation
I ooitrucuon or Frow
-yes-no -yes-no -yes-noI Diversion Berm:
I s"u,ltt)'I.tr*
-yes-no
Signs of Distress _yes_no
I Comments:
3. Summary of Activities Around Sedimentation Pond:
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White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
4. Overspray Dust Minimization:
Oversorav svstem functionins orooerlv: ves no
Overspray carried more than 50 feet from the cell: _yes_no
If "yes", was system immediately shut off?
-yes-no
9J2lOg Revision: Denison4Z
Page32 of 45
Comments:
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5. Remarks:
6. Settlement Monitors
Cell2 Wl:
Cell2W2:
Cell2 W3:
Cell2 W4:
Cell2WT-C:
Cell2 W7N:
Cell2 W6C:
Cell4A-Toe:
Cell3-2C:
Cell2W3-S:
Cell2El-N:
Cell2El-lS:
Cell2El-2S:
Cell2 East:
Cell2 W7S:
Cell2 W6S:
Cell2 W4S:
Cell3-2S:
Cell3-lN:
Cell3-lC:
Cell3-lS:
Cell3-2N:
Cell2W5-N:
Cell2 W6N:
Cell2 W4N:
Cell2 W5C:t
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7. Summary of Daily, Weekly and Quarterly Inspections:
8. Monthly Slimes Drain Static Head Measurement for Cell2 (Depth-in-Pipe Water Level
Reading):
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I I Wnit" Mesa Mill - Standard Operating ProceduresI Book I l: Environmental Protection Manual, Section 3.1
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APPENDTX A (CONT.)
WHITE MESA IVtrLL
TAILINGS MANAGEMENT SYSTEM
QUARTERLY INSPECTION DATA
912108 Revision: Denison6f
Page 33 of45
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Date:
1. Embankment Inspection:I
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3. Construction Activites:
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I Wt it" Mesa Mill - Standard Operating Procedures
Book l1: Environmental Protection Manual, Section 3.1
9J2108 Revision: Denison4T
Page 34 of 45
APPENDIX A (CONT.)
ORE STORAGE/SAMPLE PLANT WEEKLY INSPECTION REPORT
Week of _ through Date of Inspection:
Inspector:
Weather conditions for the week:
Blowing dust conditions for the week:
In,
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t Are all bulk feedstock materials stored in the area indicated on the attached diagram:ves: no:
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comments:
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Are all altemate feedstock materials located outside the area indicated on the attached diagram maintained
within water-tight containers :
ves: no:
comments (e.g., conditions of containers):
I Conditions of storage areas for materials:
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Book I l: Environmental Protection Manual, Section 3.1
912108 Revision: Denison6f
Page 35 of45
APPENDIX B
TAILINGS INSPECTOR TRAINING
This document provides the training necessary for qualifying management-designated individuals for
conducting daily tailings inspections. Training information is presented by the Radiation Safety
Officer or designee from the Environmental Department. Daily tailings inspections are conducted in
accordance with the White Mesa Mill Tailings Management System and Discharge Minimization
Technology (DMT) Monitoring Plan. The Radiation Safety Officer or designee from the Radiation
Safety Department is responsible for performing monthly and quarterly tailings inspections. Tailings
inspection forms will be included in the monthly tailings inspection reports, which summarize the
conditions, activities, and areas ofconcern regarding the tailings areas.
Notifications:
The inspector is required to record whether all inspection items are normal (satisfactory, requiring no
action) or that conditions of potential concem exist (requiring action). A "check" mark indicates no
action required. If conditions of potential concern exist the inspector should mark an "X" in the area
the condition pertains to, note the condition, and specify the corrective action to be taken. If an
observable concern is made, it should be noted on the tailings report until the corrective action is
taken and the concern is remedied. The dates of all corrective actions should be noted on the reports
as well.
Any major catastrophic events or conditions pertaining to the tailings area should be reported
immediately to the Mill Manager or the Radiation Safety Officer, one of whom will notify Corporate
Management. If dam failure occurs, notify your supervisor and the Mill Manager immediately. The
Mill Manager will then notify Corporate Management, MSHA (303-23t-5465), and the State of
Utah, Division of Dam Safety (801-538-7200).
Inspections:
All areas of the tailings disposal system are routinely patrolled and visible observations are to be
noted on a daily tailings inspection form. Refer to Appendix A for an example of the daily tailings
inspection form. The inspection form consists of three pages and is summarized as follows:
Tailings Slurry Transport System:
The slurry pipeline is to be inspected for leaks, damage, and sharp bends. The pipeline joints
are to be monitored for leaks, and loose connections. The pipeline supports are to be
3.
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I Wtrite Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
912108 Revision: Denison4Z
Page 36 of45
inspected for damage and loss of support. Valves are also to be inspected particularly for
leaks, blocked valves, and closed valves. Points of discharge need to be inspected for
improper location and orientation.
2. Operational Systems:
Operating systems including water levels, beach liners, and covered areas are items to be
inspected and noted on the daily inspection forms. Sudden changes in water levels
previously observed or water levels exceeding the operating level of a pond are potential
areas ofconcern and should be noted. Beach areas that are observed as having cracks, severe
erosion or cavities are also items that require investigation and notation on daily forms.
Exposed liner or absence of cover from erosion are potential items of concern for ponds and
covered areas. These should also be noted on the daily inspection form.
Cells 1, 3 and 4,A. solution levels are to be monitored closely for conditions nearing
maximum operating level and for large changes in the water level since the last inspection.
All pumping activities affecting the water level will be documented. In Cells I and 3, the
PVC liner needs to be monitored closely for exposed liner, especially after storm events. It is
important to cover exposed liner immediately as exposure to sunlight will cause degradation
of the PVC liner. Small areas of exposed liner should be covered by hand. Large sections of
exposed liner will require the use of heavy equipment
These conditions are considered serious and require immediate action. After these conditions
have been noted to the Radiation Safety Officer, a work order will be written by the
Radiation Safety Officer and turned into the Maintenance Department. All such repairs
should be noted in the report and should contain the start and finish date of the repairs.
Dikes and Embankments:
Inspection items include the slopes and the crests of each dike. For slopes, areas of concern
are sloughs or sliding cracks, bulges, subsidence, severe erosion, moist areas, and areas of
seepage outbreak. For crests, areas ofconcern are cracks, subsidence, and severe erosion.
When any of these conditions are noted, an "X" mark should be placed in the section marked
for that dike.
In addition, the dikes, in particular dikes 3, 4A-S and 4A-W, should be inspected closely for
mice holes and more importantly for prairie dog holes, as the prairie dogs are likely to
burrow in deep, possibly to the liner. If any of these conditions exist, the inspection report
should be marked accordingly.
FIow Rates:4.
5.
6.
7.
8.
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White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
912108 Revision : Denison62
Page 37 of45
Presence of all flows in and out of the cells should be noted. Flow rates are to be estimated
in gallons per minute (GPM). Rates need to be determined for slurry lines, pond return, SX-
tails, and the spray system. During non-operational modes, the flow rate column should be
marked as "0". The same holds true when the spray system is not utilized.
Physical Inspection of Slurry Line(s):
A physical inspection of all slurry lines has to be made every4 hours during operation of the
mill. If possible, the inspection should include observation of the entire discharge line and
discharge spill point into the cell. If "flll to elevation" flags are in place, the tailings and
build-up is to be monitored and controlled so as to not cover the flags.
Dust Control:
Dusting and wind movement of tailings should be noted for Cells 2,3, and 4A. Other
observations to be noted include a brief description of present weather conditions, and a
record of any precipitation received. Any dusting or wind movement of tailings should be
documented. In addition, an estimate should be made for wind speed at the time of the
observed dusting or wind movement of tailings.
The Radiation Safety Department measures precipitation on a daily basis. Daily
measurements should be made as near to 8:00 a.m. as possible every day. Weekend
measurements will be taken by the Shifter as close to 8:00 a.m. as possible. All snow or ice
should be melted before a reading is taken.
Observations of Potential Concern:
All observations of concern during the inspection should be noted in this section. Corrective
action should follow each area of concern noted. All work orders issued, contacts, or
notifications made should be noted in this section as well. It is important to document all
these items in order to assure that the tailings management system records are complete and
accurate.
Map of Tailings Cells:
The last section of the inspection involves drawing, as accurately as possible, the following
items where applicable.
1. Cover area
2. Beach/tailing sands area
3. Solution as it exists
4. Pump lines
9.
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White Mesa Mill - Standard Operating Procedures
Book I I : Environmental Protection Manual, Section 3.1
912 108 Revision: Denison6Z
Page 38 of45
5. Activities around tailings cell (i.e. hauling trash to the dump, liner repairs, etc.)6. Slurry discharge when operating
7. Over spray system when operating
Safety Rules:
All safety rules applicable to the mill are applicable when in the tailings area. These rules
meet the required MSHA regulations for the tailings area. Please pay particular notice to the
following rules:
1. The posted speed limit for the tailings area is 15 mph and should not be exceeded.
2. No food or drink is permitted in the area.
3. All personnel entering the tailings area must have access to a two-way radio.4. Horseplay is not permitted at any time.
5. Only those specifically authorized may operate motor vehicles in the restricted area.6. When road conditions are muddy or slick, a four-wheel drive vehicle is required in the
area.
7. Any work performed in which there is a danger of falling or slipping in the cell will
require the use of a safety belt or harness with attended life line and an approved life
jacket. A portable eyewash must be present on site as well.
8. Anytime the boat is used to perform any work; an approved life jacket and goggles must
be worn at all times. There must also be an approved safety watch with a two-way hand-
held radio on shore. A portable eyewash must be present on site as well.
Preservation of Wildlife:
Every effort should be made to prevent wildlife and domesticated animals from entering the
tailings area. All wildlife observed should be reported on the Wildlife Report Worksheet
during each shift. Waterfowl seen near the tailings cells should be discouraged from Ianding
by the use of noisemakers.
Certification:
Following the review of this document and on-site instruction on the tailings system
inspection program, designated individuals will be certified to perform daily tailings
inspections. The Radiation Safety Officer authorizes certification. Refer to the Certification
Form, Appendix C. This form should be signed and dated only after a thorough review of the
tailings information previously presented. The form will then be signed by the Radiation
Safety Officer and filed.
10.
11.
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I I Wnit" Mesa Mitl - Standard Operating ProceduresI Book I l: Environmental Protection Manual, Section 3.1
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I Date:
9)2108 Revision : Denison6Z
Page 39 of 45
APPENDIX C
CERTIFICATION FORM
I
Name:
I have read the document titled "Tailings Management System, White Mesa Mill Tailings
I lnspector Training" and have received on-site instruction at the tailings system. This instruction
f included documentation of daily tailings inspections, analysis of potential problems (dike
failures, unusual flows), notification procedures and safety.
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I certify that the above-named person is qualified to perform the daily inspection of the tailings
I systern at the White Mesa Mill.
Signature
Radiation Safety Personnel/ Tailings System
Supervisor
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Book I l: Environmental Protection Manual, Section 3.1 Page 40 of 45
I APPEND* D
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FEEDSTOCK STORAGE AREA
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Book I l: Environmental Protection Manual, Section 3.1
91708 Revision: Denison42
Page4l of45
APPENDD( E
TABLES
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- Book I l: Environmental Protection Manual, Section 3.1 Page 42 of 45
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Table I
Calculated Action leakage Rates
for Various head Conditions
Cell44. White mesa Mill
Blanding, Utah
Head above Liner System (feet)Calculated Action leakage Rate
( sallons I acre / dav )
5 222.04
10 314.0r
15 384.58
20 444.08
25 496.50
30 543.88
35 587.46
37 604.01
White Mesa Mill - Standard Operating Procedures 912108 Revision: Denison6Z
Book I I : Environmental Protection Manual, Section 3. I Page 43 of 45
APPENDIX F
Example of Freeboard Calculations
For Cell4A
Assumptions and Factors:
o Total PMP volume to be stored in Cell 4A - 159.4 acre feeto Wave runup factor for Cell44. - 0.77 feeto Total capacity of Cell 4A - 2.094.000 dry tonso Elevation of FML of Cell4,{ - 5.598.5 FMSLo Maximum oool surface area of Cell 4,{ - 40 acreso Total tailings solids deposited into Cell 4A at time beach area first exceeds 5.593
FMSL - 1.000.000 drv tons*o Date beach area first exceeds 5.593. FMSL - March 1. 2009xo Expected and actual production is as set forth in the following table:
Time Period Expected
Tailines Solids
Disposition intoCell 4A
Determined at
the beeinnine of
the period (drv
tons)*
Expected
Tailines
Solids
Dispositio
n into Cell
4A at the
beeinnins
of the
Deriod.
multiplied
bv l50%o
Safetv
Factor
(drv tons)
Actual Tailines
Solids
Disposition intoCell 4A
determined atend of theperiod (drv
tons)*
March l. 2009
to November l.
2009
150.000 225.ON 225.OOO
November l.2009 to
November l.
20ro
300.000 450.000 275.O40
November 1.2010 to
November l.
2011
200.000 300.000 250.000
White Mesa Mill - Sundard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
9)2108 Revision: Denison6Z
Page 44 of 45
*These expected and actual tailings and production numbers and dates are fictional andhave
been assumed for illustrative purposes only.
Based on these assumptions and factors. the freeboard limits for Cell 4A would be calculated
as follows:
1. Prior to March l. 2009
Prior to March l. 2009. the maximum elevation of the beach area in Cell 4 is less than or
equal to 5.593 FMSL. therefore the freeboard limit is set at 5.593.7 FMSL.
2. March 1.2009 to November 1. 2009
The pool surface area would be reduced to the following amount
( I - 225.000./ (2.094.000 - I .000.000)) x 40 acres = 31.77 acres
Based on this reduced pool area. the amount of freeboard would be 159.4 acre feet divided by 3 I .77
acres equals 5.02 feet. When the wave run up factor for Cell 4A of 0.77 feet is added to this. the total
freeboard required is 5.79 feet. This means that the freeboard limit for Cell4,A, would be reduced
from 5593.7 FMSL to 5592.7 FMSL (5598.5 FMSL minus 5.79 feet. rounded to the nearest one-
tenth of a foot). This calculation would be performed at March l. 2009. and this freeboard limit
would persist until November l. 2009.
3. November l. 2009 to November 1. 2010
The pool surface area would be reduced to the following amount:
First. recalculate the pool surface area that should have applied during the previous period.
had modeled tonnages (i.e.. expected tonnages grossed upbythe 1507o safetyfactor) equaled
actual tonnages for the period. Since the actual tonnaee of 225.000 dry tons was the same as
the modeled tonnage of 225.000 dry tons. the recalculated pool surface area is the same as
the modeled pool surface area for the previous period. which is 31.77 acres.
Then. calculate the modeled pool surface area to be used for the period:
(l - 450.000/ (2.094.000 - 1.000.000 - 225.000)) x 31.77 acres = 15.32 acres
Based on this reduced pool area. the amount of freeboard would be 159.4 acre feet divided by
15.32 acres equals 10.40 feet. When the wave run uo factor for Cell4A of 0.77 feet is added
to this. the total freeboard required is I I . 17 feet. This means that the freeboard limit for Cell
4A would be reduced from 5592.7 FMSL to 5587.3 FMSL (5598.5 FMSL minus I l.17 feet.
rounded to the nearest one-tenth of a foot). This calculation would be performed at
November l. 2009. and this freeboard limit would persist until November 1.2010.
White Mesa Mill - Standard Operating Procedures
Book I l: Environmental Protection Manual, Section 3.1
912108 Revision: Denison6Z
Page 45 of45
4. November l. 2010 to November l. 2011
The pool surface area would be reduced to the following amount:
First. recalculate the pool surface area that should have applied during the previous period.
had modeled tonnages (i.e.. expected tonnages grossed up by the 1507o safety factor) equaled
actual tonnages for the period. Since modeled tonnages exceeded actual tonnages. the pool
area was reduced too much during the previous period. and must be adjusted. The
recalculated pool area for the previous period is:
(l -275.000/ (2.094.000 - 1.000.000 - 225.000) x 31.77 acres = 21.72 acres.
This recalculated oool surface area will be used as the starting point for the freeboard
calculation to be performed at November 1. 2010.
Then. calculate the modeled pool surface area to be used for the period:
Based on this reduced pool area. the amount of freeboard would be 159.4 acre feet divided b),
10.75 acres equals 14.83 feet. When the wave run up factor for Cell4,A, of 0.77 feet is added
tothis.thetotalfreeboardrequiredis 15.60feet. ThismeansthatthefreeboardlimitforCell
44. would be reduced from 5587.3 FMSL to 5582.9 FMSL (5598.5 FMSL minus 15.60 feet.
rounded to the nearest one-tenth of a foot). This calculation would be performed at
November 1. 2010. and this freeboard limit would persist until November l. 201l.
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APPENDIX C
Cell4A BAT Monitoring, Operations and Maintenance Plan
Introduction
Construction of Cell 4A was authorized by the Utah Department of Environmental
Quality, Division of Radiation Control ("DRC) on June 25,2OO7. The construction
authorization provided that Cell44, shall not be in operation until after a BAT
Monitoring, Operations and Maintenance Plan is submitted for Executive Secretary
review and approval. The Plan shall include requirements in Pan F.3 of the Groundwater
Discharge Permit No. UGW37AAO4 ("GWDP") and full fill the requirements of Parts
I.D.6, I.E.8, and I.F.S of the GWDP.
Cell Desien
Tailings Cell 4A consists of the following major elements:
a) Dikes - consisting of earthen embankments of compacted soil, constructed
between 1989-1990, and composed of four dikes, each including a l5-foot
wide road at the top (minimum). On the north, east, and south margins these
dikes have slopes of 3H to lV. The west dike has a interior slope of 2H to
lV. Width of these dikes varies; each has a minimum crest width of at least
15 feet to support an access road. Base width also varies from 89-feet on the
east dike (with no exterior embankment), to 21l-feet at the west dike.
b) Foundation - including subgrade soils over bedrock materials. Foundation
preparation included excavation and removal of contaminated soils,
compaction of imported soils to a maximum dry density of 9O7o. Floor of
Cell 44, has an average slope of l7o that grades from the northeast to the
southwest corners.
c) Tailings Capacity - the floor and inside slopes of Cell 4^A encompass about 40
acres and have a maximum capacity of about 1.6 million cubic yards of
tailings material storage (as measured below the required 3-foot freeboard).
d) Liner and lrak Detection Systems - including the following layers, in
descending order:
1) Primary Flexible Membrane Liner (FML) - consisting of impermeable 60
mil high density polyethylene (HDPE) membrane that extends across both
the entire cell floor and the inside side-slopes, and is anchored in a trench
at the top of the dikes on all four sides. The primary FML will be in direct
physical contact with the tailings material over most of the Cell 44. floor
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In other locations, the primary FML will be in contact with the
drain collection system (discussed below).
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Cell 4,{ BAT Monitoring, Operations and Maintenance Plan 09/08 Revision Denison 1.3
2) Leak Detection System - includes a permeable HDPE geonet fabric that
extends across the entire area under the primary FML in Cell 4,{, and
drains to a leak detection sump in the southwest corner. Access to the leak
detection sump is via an l8-inch inside diameter (ID) PVC pipe placed
down the inside slope, located between the primary and secondary FML
liners. At its base this pipe will be surrounded with a gravel filter set in
the leak detection sump, having dimensions of 10 feet by 10 feet by 2 feet
deep. In turn, the gravel filter layer will be enclosed in an envelope of
geotextile fabric. The purpose of both the gravel and geotextile fabric is to
serve as a filter.
3) Secondary FML - consisting of an impermeable 60-mil HDPE membrane
found immediately below the leak detection geonet. Said FML also
extends across the entire Cell 4,A. floor, up the inside side-slopes and is
also anchored in a trench at the top of all four dikes.
4) Geosynthetic Clay Liner - consisting of a manufactured geosynthetic clay
liner (GCL) composed of 0.2-inch of low permeability bentonite clay
centered and stitched between two layers of geotextile. Prior to disposal
of any wastewater in Cell 4A, the Permittee shall demonstrate that the
GCL has achieved a moisture content of at least 50Vo by weight. This
item is a revised requirement per DRC letter to DUSA dated September
29,2007
e) Slimes Drain Collection System - including a two-part system of strip drains
and perforated collection pipes both installed immediately above the primary
FML, as follows:
1) Horizontal Strip Drain System - is installed in a heningbone pattern
across the floor of Cell 4A that drain to a "backbone" of perforated
collection pipes. These strip drains are made of a prefabricated two-part
geo-composite drain material (solid polymer drainage strip) core
surrounded by an envelope of non-woven geotextile filter fabric. The strip
drains are placed immediately over the primary FML on 50-foot centers,
where they conduct fluids downgradient in a southwesterly direction to a
physical and hydraulic connection to the perforated slimes drain collection
pipe. A series of continuous sand bags, filled with filter sand cover the
strip drains. The sand bags are composed of a woven polyester fabric
filled with well graded filter sand to protect the drainage system from
plugging.
2) Horizontal Slimes Drain Collection Pipe System - includes a "backbone"
piping system of 4-inch ID Schedule 40 perforated PVC slimes drain
collection (SDC) pipe found at the downgradient end of the strip drain
lines. This pipe is in turn overlain by a berm of gravel that runs the entire
diagonal length of the cell, surrounded by a geotextile fabric cushion in
immediate contact with the primary FML. [n turn, the gravel is overlain
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Cell 44, BAT Monitoring, Operations and Maintenance Plan 09/08 Revision Denison 1.3
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by a layer of non-woven geotextile to serve as an additional filter material.
This perforated collection pipe serves as the "backbone" to the slimes
drain system and runs from the far northeast corner downhill to the far
southwest corner of Cell 44, where it joins the slimes drain access pipe.
3) Slimes Drain Access Pipe - consisting of an lS-inch ID Schedule 40 PVC
pipe placed down the inside slope of Cell 4,4, at the southwest corner,
above the primary FML. Said pipe then merges with another horizontal
pipe of equivalent diameter and material, where it is enveloped by gravel
and woven geotextile that serves as a cushion to protect the primary FML.
A reducer connects the horizontal lS-inch pipe with the 4-inch SDC pipe.
At some future time, a pump will be set in this l8-inch pipe and used to
remove tailings wastewaters for purposes of de-watering the tailings cell.
Dike Splash Pads - A minimum of eight (8) l0-foot wide splash pads are
installed on the interior dike slopes to protect the primary FML from abrasion
and scouring by tailings slurry. These pads will consist of an extra layer of 60
mil HDPE membrane that will be placed down the inside slope of Cell 4A,,
from the top of the dike and down the inside slope. The pads on the north side
of the Cell will extend to a point 5-feet beyond the toe of the slope to protect
the liner bottom during initial startup of the Cell. The exact location of the
splash pads is detailed on the As-Built Plans and Specifications.
Emergency Spillway - a concrete lined spillway constructed near the western
corner of the north dike to allow emergency runoff from Cell 3 into Cell 4,{.
This spillway will be limited to a 6-inch reinforced concrete slab set directly
over the primary FML in a 4-foot deep trapezoidal channel. No other spillway
or overflow structure will be constructed at Cell 44. All stormwater runoff
and tailings wastewaters not retained in Cells 2 and 3, will be managed and
contained in Cell 44, including the Probable Maximum Precipitation and
flood event.
Cell Ooeration
Solution Discharge
Cell 4A will initially be used for storage and evaporation of process solutions
from the Mill operations. These process solutions will be from the
uranium/vanadium solvent extraction circuit, or transferred from Cell 1
evaporation pond or the free water surface from Cell 3. The solution will be
pumped to Cell4,A. through 6 inch or 8 inch diameter HDPE pipelines. The initial
solution discharge will be in the southwest corner of the Cell. The discharge pipe
will be routed down the Splash Pad provided in the corner of the Cell to protect
the pipeline running from the solution reclaim barge. The solution will be
discharged in the bottom of the Cell, away from any sand bags or other
installation on the top of the FML. Building the solution pool from the low end of
the Cell will allow the solution pool to gradually rise around the slimes drain
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Cell 4A BAT Monitoring, Operations and Maintenance Plan 09/08 Revision Denison 1.3
strips, eliminating any damage to the strip drains or the sand bag cover due to
solution flowing past the drainage strips. The solution will eventually be
discharged along the dike between Cell 3 and Cell 4A,, utilizing the Splash Pads
described above. The subsequent discharge of process solutions will be near the
floor of the pond, through a discharge header designed to discharge through
multiple points, thereby reducing the potential to damage the Splash Pads or the
Slimes Drain system. At no time will the solution be discharged into less than 2
feet of solution. As the cell begin to fill with solution the discharge point will be
pull back up the Splash Pad and allowed to continue discharging at or near the
solution level.
Initial Solids Discharge
Once Cell 44. is needed for storage for tailings solids the slurry discharge from
No. 8 CCD thickener will be pumped to the cell through 6 inch or 8 inch diameter
HDPE pipelines. The pipelines will be routed along the dike between Cell 3 and
Cell4,A', with discharge valves and drop pipes extending down the Splash Pads to
the solution level. One or all of the discharge points can be used depending on
operational considerations. Solids will settle into a cone, or mound, of material
under the solution level, with the courser fraction settling out closer to the
discharge point. The initial discharge locations are shown on Figure 1. Figure 2
illustrates the general location of the solution and slurry discharge pipelines and
control valve locations. The valves are 6" or 8" stainless steel knife-gate valves.
The initial discharge of slurry will be at or near the toe of the Cell slope and then
gradually moved up the slope, continuing to discharge at or near the water
surface. This is illustrated in Section A-A on Figure 2. Because of the depth of
Cell 4A, each of the discharge points will be utilized for an extended period of
time before the cone of material is above the maximum level of the solution. The
discharge location will then moved further to the interior of the cell allowing for
additional volume of solids to be placed under the solution level. The solution
level in the cell will vary depending on the operating schedule of the Mill and the
seasonal evaporation rates. The tailings slurry will not be allowed to discharge
directly on to the Splash Pads, in order to further protect the FML. The tailings
slurry will discharge directly in to the solution contained in the Cell, onto an
additional protective sheet, or on to previously deposited tailings sand.
Equipment Access
Access will be restricted to the interior portion of the cell due to the potential to
damage the flexible membrane liner. Only rubber tired all temain vehicles or foot
traffic will be allowed on the flexible membrane liner. Personnel are also
cautioned on the potential damage to the flexible membrane liner through the use
and handling of hand tools and maintenance materials.
Reclaim Water Svstem
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I Cett 4A BAT Monitoring, Operations and Maintenance Plan
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09/08 Revision Denison 1.3
A pump barge and solution recovery system will be installed in the southwest
corner of the cell to pump solution from the cell for water balance purposes or for
re-use in the Mill process. Figure 3 illustrates the routing of the solution return
pipeline and the location of the pump barge. The pump barge will be constructed
and maintained to ensure that the flexible membrane liner is not damaged during
the initial filling of the cell or subsequent operation and maintenance activities.
The condition of the pump barge and access walkway will be noted during the
weekly Cell inspections.
Interim Solids Discharge
Figure 4 illustrates the progression of the slurry discharge points around the east
side of Cell 4A. Once the tailings solids have been deposited along the north and
east sides of the Cell, the discharges points will subsequently be moved to the
sand beaches, which will eliminate any potential for damage to the liner system.
Liner Maintenance and OA/OC
Any construction defects or operational damage discovered during observation of
the flexible membrane liner will be repaired, tested and documented according to
the procedures detailed in the approved Revised construction Quality
Assurance Plan for the Construction of the Cell 4A Lining System, May
2007, by GeoSyntec Consultants.
BAT Performance Standards for Tailinss Cell4A
DUSA will operate and maintain Tailings Cell 4,A. so as to prevent release of wastewater
to groundwater and the environment in accordance with this BAT Monitoring Operations
and Maintenance Plan, pursuant to Part I.H.19 of the GWDP. These performance
standards shall include:
1) lrak Detection System Pumping and Monitoring Equipment - the
leak detection system pumping and monitoring equipment, includes a
submersible pump, pump controller, water level indicator (head
monitoring), and flow meter with volume totalizer. The pump controller
is set to maintain the maximum level in the leak detection system at no
more than I foot above the lowest level of the secondary flexible
menbrane. A second leak detection pump with pressure transducer, flow
meter, and manufacturer recommended spare parts for the pump controller
and water level data collector is maintained in the Mill warehouse to
ensure that the pump and controller can be replaced and operational within
24 hours of detection of a failure of the pumping system. The root cause
of the equipment failure will be documented in a report to Mill
management with recommendations for prevention of a re-occurrence.
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Maximum Allowable Head - the Permittee shall measure the fluid head
above the lowest point on the secondary flexible membrane by the use of
procedures and equipment specified in the White Mesa Mill Tailings
Management System and Discharge Minimization Technology
(DMT) monitoring Plan, 3l+7W. Revision : Denison 32..(!hg
"DMT Plan"), or the currently approved DMT Plan. Under no
circumstance shall fluid head in the leak detection system sump exceed a
1-foot level above the lowest point in the lower flexible membrane liner.
Maximum Allowable Daily LDS Flow Rates - the Permittee shall
measure the volume of all fluids pumped from the LDS on a weekly
basis, and use that information to calculate an average volume pumped
per day. Under no circumstances shall the daily LDS flow volume
exceed 24,160 gallons/day. The maximum daily LDS flow volume will
be compared against the measured cell solution levels detailed on the
attached Table 1 to determine the maximum daily allowable LDS flow
volume for varying head conditions in the cell. .
3-foot Minimum Vertical Freeboard Criteria - the Permittee shall
operate and maintain wastewater levels to provide a 3-foot Minimum of
vertical freeboard in Tailings Cell4A. Said measurements shall be
made to the nearest 0.1 foot.
Slimes Drain Recovery Head Monitoring - immediately after the
Permittee initiates pumping conditions in the Tailings Cell 44. slimes
drain system, monthly recovery head tests and fluid level measurements
will be made in accordance with a plan approved by the DRC Executive
Secretary. The slimes drain system will pumping and monitoring
equipment, includes a submersible pump, pump controller, water level
indicator (head monitoring), and flow meter with volume totalizer.
Routine Maintenance and Monitorine
Trained personnel inspect the White Mesa tailings system on a once per day basis. Any
abnormal occurrences or changes in the system will be immediately reported to Mill
management and maintenance personnel. The inspectors are trained to look for events
involving the routine placement of tailings material as well as events that could affect the
integrity of the tailings cell dikes or lining systems. The daily inspection reports are
summarized on a monthly basis and reviewed and signed by the Mill Manager.
Solution Elevation
Measurements of solution elevation in Cell 4A are to be taken by survey on a
weekl y b as i s"as-f,elle+wi
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Cell 4A BAT Monitoring, Operations and Maintenance Plan 09/08 Revision Denison 1.3
@. and measurements of the beach area in Cell4A
with the
tns*ument") aeeurat
@
rcvefftnnsl-I
the applieable Referenee Peirt and pend surfaee are visible. Fer €ell4r\;
(9eree i+leeatien; the Surveyer will ensure that the Survey krstrument is
a-leYefreagingi
is
where the ^ide slepe dlews fer safe aeee's te the selutier surfaee,
the Strrrrc:'Red is vertieal by gently reeld'rg the red baek and fe*h until
in&
is
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Cell 4A BAT Monitoring, Operations and Maintenance Plan 09/08 Revision Denison 1.3
elevation@in
ffiare to be taken by survey on a monthly basis.
by the use of the procedures and equipment specified in Section 3.1 of the
DMT Plan.
Leak Detection System
The Lrak detection system is monitored on a continuous basis by use of a
pressure transducer that feeds water level information to an electronic data
collector. The water levels are measured every hour and the information
is stored for later retrieval. The water levels are measured to the nearest
0.10 inch. The data collector is currently programmed to store 7 days of
water level information. The number of days of stored data can be
increased beyond 7 days if needed. The water level data is downloaded to
a laptop computer on a weekly basis and incorporated into the Mill's
environmental monitoring data base, and into the files for weekly
inspection reports of the tailings cell leak detection systems. Within 24
hours after collection of the weekly water level data, the information will
be evaluated to ensure that: 1) the water level in the leak detection sump
did not exceed the allowable level (5556.14 feet amsl), and2) the average
daily flow rate from the LDS did not exceed the maximum daily allowable
flow rate at any time during the reporting period. For Cell 4,{, under no
circumstance shall fluid head in the leak detection system sump exceed a
l-foot level above the lowest point in the lower flexible membrane liner.
To determine the Maximum Allowable Daily LDS Flow Rates in the Cell
4A leak detection system, the total volume of all fluids pumped from the
LDS on a weekly basis shall be recovered from the data collector, and that
information will be used to calculate an average volume pumped per day.
Under no circumstances shall the daily LDS flow volume exceed 24,160
gallons/day. The maximum daily LDS flow volume will be compared
against the measured cell solution levels detailed on the attached Table 1,
to determine the maximum daily allowable LDS flow volume for varying
head conditions in Cell 4,\. Any abnormal or out of compliance water
levels must be immediately reported to Mill management. The data
collector is also equipped with an audible alarm that sounds if the water
level in the leak detection sump exceeds the allowable level (5556.14 feet
amsl). The current water level is displayed at all times on the data
collector and available for recording on the daily inspection form. The
leak detection system is also equipped with a leak detection pump, EPS
Model # 25505-3 stainless steel, or equal. The pump is capable of
pumping in excess of 25 gallons per minute at a total dynamic head of 50
feet. The pump has a 1.5 inch diameter discharge, and operates on 460
volt 3 phase power. The pump is equipped with a pressure sensing
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transducer to start the pump once the level of solution in the leak detection
sump is approximately 2.25 feet (elevation 5555.89) above the lowest
level of the leak detection sump (9 inches above the lowest point on the
lower flexible membrane liner, to ensure the allowable 1.0 foot (5556.14
feet amsl) above the lowest point on the lower flexible membrane liner is
not exceeded). The attached Figure 6, Leak Detection Sump Operating
Elevations, illustrates the relationship between the sump elevation, the
lowest point on the lower flexible membrane liner and the pump-on
solution elevation for the leak detection pump. The pump also has manual
start and stop controls. The pump will operate until the solution is drawn
down to the lowest level possible, expected to be approximately 4 inches
above the lowest level of the sump (approximate elevation 5554.0). The
pump discharge is equipped with a 1.5 inch flow meter, EPS Paddle
Wheel Flowsensor, or equal, that reads the pump discharge in gallons per
minute, and records total gallons pumped. The flow rate and total gallons
is recorded by the Inspector on the weekly inspection form. The leak
detection pump is installed in the horizontal section of the 18 inch,
horizontal, perforated section of the PVC collection pipe. The distance
from the top flange face, at the collection pipe invert, to the centerline of
the 22.5 degree elbow is 133.4 feet, and the vertical height is
approximately 45 feet. The pump is installed at least 2 feet beyond the
centerline of the elbow. The bottom of the pump will be installed in the
leak detection sump at least 135.4 feet or more from the top of the flange
invert. A pressure transducer installed with the pump continuously
measures the solution head and is programmed to start and stop the pump
within the ranges specified above. The attached Figure 5 illustrates the
general configuration of the pump installation.
A second leak detection pump with pressure transducer, flow meter, and
manufacturer recofilmended spare parts for the pump controller and water
level data collector will be maintained in the Mill warehouse to ensure that
the pump and controller can be replaced and operational within 24 hours
of detection of a failure of the pumping system. The root cause of the
equipment failure will be documented in a report to Mill management with
recommendations for prevention of a re-occurrence.
Slimes Drain System
(i) A pump, Tsurumi Model # KTZ23.7-62 stainless steel, or equal, will be
placed inside of the slimes drain access riser pipe and a near as possible to
the bottom of the slimes drain sump. The bottom of the slimes drain sump
is 38 feet below a water level measuring point at the centerline of the
slimes drain access pipe, near the ground surface level. The pump
discharge will be equipped with a 2 inch flow meter,ElH Model #33, or
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equal, that reads the pump discharge in gallons per minute, and records
total gallons pumped. The flow rate and total gallons will be recorded by
the Inspector on the weekly inspection form.
(ii) The slimes drain pump will be on adjustable probes that allows the pump
to be set to start and stop on intervals determined by Mill management.
(iii)The Cell 4,A. slimes drain pump will be checked weekly to observe that it
is operating and that the level probes are set properly, which is noted on
the Weekly Tailings Inspection Form. If at any time the pump is observed
to be not working properly, it will be repaired or replaced within 15 days;
(iv)Depth to wastewater in the Cell 4A slimes drain access riser pipe shall be
monitored and recorded weekly to determine maximum and minimum
fluid head before and after a pumping cycle, respectively. All head
measurements must be made from the same measuring point, to the
nearest 0.01 foot. The results will be recorded as depth-in-pipe
measurements on the Weekly Tailings Inspection Form;
(v) On a monthly basis, the slimes drain pump will be turned off and the
wastewater in the slimes drain access pipe will be allowed to stabilize for
at least 90 hours. Once the water level has stabilized (based on no change
in water level for three (3) successive readings taken no less than one (l)
hour apart) the water level of the wastewater will be measured and
recorded as a depth-in-pipe measurement on the Monthly Inspection Data
form, by measuring the depth to water below the water level measuring
point on the slimes drain access pipe;
The slimes drain pump will not be operated until Mill management has
determined that no additional process solutions will be discharged to Cell4A,, and
the Cell has been partially covered with the first phase of the reclamation cap.
The long term effectiveness and performance of the slimes drain dewatering will
be evaluated on the same basis as the currently operating slimes drain system for
Cell2.
Tailinss Emersencies
Inspectors will notify the Radiation Safety Officer and./or Mill management immediately
if, during their inspection, they discover that an abnormal condition exists or an event has
occurred that could cause a tailings emergency. Until relieved by the Environmental or
Radiation Technician or Radiation Safety Officer, inspectors will have the authority to
direct resources during tailings emergencies.
Any major catastrophic events or conditions pertaining to the tailings area should be
reported immediately to the Mill Manager or the Radiation Safety Officer, one of whom
will notify Corporate Management. If dam failure occurs, notify your supervisor and the
Mill Manager immediately. The Mill Manager will then notify Corporate Management,
MSHA (303-231-5465), and the State of Utah, Division of Dam Safety (801-538-7200).
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Cell 4,ar BAT Monitoring, Operations and Maintenance Plan 09/08 Revision Denison 1.3
Cell 4A Solution Freeboard Calculation
The maximum tailings cell pond wastewater levels in Cells l{Sll4€elt3 and Cell44
are regulated by condition 10.3 of the White Mesa Mill 1le.(z) Materials License,
periegiealty, in accordance with tleprocedures set out in
the previeusly a-preved NRG lieerse apprieatien; ineluding the eebber 13; 1999
the DMT Plan.
Condition 10.3 states that "The Freeboard limit for Cell I shall be 5615.4 feet above
mean sea level. and the freeboard limit for Cell $Sshall be reeateula*a6g!!
annually in accordance with the procedures set i
ut in Section 6.3 of the White
Mesa Mill Tailings Manaeement Svstem and Discharee Minimization Technoloev
(DMT) Monitorins Plan. which is included as Section 3.1 of the Mill's
Environmental Protection Prosram. Said calculations shall be submitted as part of
the annual Technical Evaluation Reoort. Said report shall be submitted for
Executive Secretarv approval no later than September 1. of each vear."
The freeboard limits set out in Section 6.3 of the DMT Plan are intended to capture the
Local6-hourProbableMaximumPrecipitation(PMP)event@
reqpi . which was determined in the
January 10. 1990 Drainage Report for the White Mesa site irlo be l0 inches.
Based on the PMP storm event, the freeboard requirement for Cell 1 is a maximum
operating water level of 5615.4 feet above mean sea level (amsl). The Cell 1 freeboard
limit is not affected by operations or conditions in Cells 2, 3 or 44.
€el+Glb 2 hasand 3_have no freeboard limit because
or near full of tailings solids and all precipitation falling on €ellCe[lE 2 and 3 and the
adjacent drainage area must be contained in Cell % The flood volume from the PMP
event over the Cell 2 and Cell 3 pond areas, plus the adjacent drainage areas, which must
be contained in Cell4,A,. is 123.4 acre-feet of water.@
feerams#
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Cell 4A BAT Monitoring, Operations and Maintenance Plan
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inte€ell4
The flood volume from the PMP event over the Cell 4,{ area is 36 acre-feet of water (40
acres, plus the adjacent drainage area of 3.25 acres, times the PMP of 10 inches). This
would result in a total flood volume of 98159.11acre-feet, including thee!23A acre-feet
of setutienwatef from@llr 2 anc!
i€Fis
calculating the freeboard limit for Cell44, is set out in Section 6.3 of the DMT Plan.
The Groundwater Quality Discharge Permit, No. UGW370004, for the White Mesa Millrequiresthattheminimumfreeboardbenolessthan3.0feetfor@
eenstrnreti@!]slang!:[1\,butbasedon
Section 6.3 of the DMT Plan. the freeboard limits for Cells I and 4A will be at least three
feet.
Figure 7, Hydraulic Profile Schematic, shows the relationship between the Cells, and the
relative elevations of the solution pools and the spillway elevations.
The required freeboard for Cell 4,A' will be recalculated annuallydeng with+h€{}
.
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Cell 4A BAT Monitoring, Operations and Maintenance Plan 09/08 Revision Denison
Attachments
Figure l, Initial Filling Plan, GeoSyntec Consultants
Figure 2, Initial Filling Plan, Details and Sections, GeoSyntec Consultants
Figure 3, Initial Filling Plan, Solution and Slury Pipeline Routes, GeoSyntec
Consultants
4) Figure 4, lnterim Filling Plan, GeoSyntec Consultants
5) Figure 5, l€ak Detection System Sump, GeoSyntec Consultants
6) Figure 6, Leak Detection Sump Operating Elevations
7) Figure 7, Hydraulic Profile Schematic
ienI98) Table 1, Calculated Action leakage Rates for Various Head Conditions,
Cell44, White Mesa Mill, Blanding, Utah, GeoSyntec Consultants
'rc)9) White Mesa Mill Tailings Management System and Discharge Minimization
Technology (DMT) Monitoring Plan, 3lUl)21O8 Revision: DUSA4#Z
pagesZ, or currently approved version of the DMT
1)
2)
3)
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