ML20015A369
| ML20015A369 | |
| Person / Time | |
|---|---|
| Issue date: | 01/08/2020 |
| From: | NRC/OCIO |
| To: | |
| Shared Package | |
| ML20015A350 | List:
|
| References | |
| FOIA, NRC-2019-000132, NRC-2020-000076 | |
| Download: ML20015A369 (54) | |
Text
SOURCE MATERIALS LICENSE SUA-1358, DOCKET No. 40-8681 Addltlonal Clarlflcatlons to White Mesa MIii Reclamation Plan Aprll15,1999
CORPORATION lndependt>nce Plaza, Suitt* 9.50
- 1050 Seventt>enth Strt*et
- 0(*nvn, CO 8026.5 * :3();3 628 77Y8 ( rnai11) * :l():3 :3k~..J 125 i fa, 1 April 15, 1999 Via Fas and Ovemi&ht Federal Express Mail Mr. N. King Stablein, Acting Branch Chief High Level Waste and Uranium Recovery Projects Branch Division of Waste Management Office of Nuclear Material Safety and Safeguards U.S. Nuclear Regulatory Commission 2 White Flint North, Mail Stop T-7 J9 11545 Rockville Pike Rockville, MD 20852 Re:
Source Materials License SUA-1358, Docket No. 40-8681 Additional Clarifications to White Mesa Mill Reclamation Plan
Dear Mr. Stablein:
Enclosed please find responses and clarification to several items related to the White Mesa Mill Reclamation Plan. These items were discussed with NRC staff during a meeting held March 24, I 999, at the White Mesa Mill site, as well as several informal follow-up conference calls. Responses to NRC questions related to the potential of the tailings sands to liquify under earthquake loading, and clarifications to the QA/QC plans for cleanup of windblown contamination will be submitted under separate cover.
Included in this submittal are the following items:
- 1)
Details of a soil sampling program to characterize the materials to be used for Random Fill and Frost Barrier. The results of this program should be available within 30 days.
- 2)
Revisions to Attachment A of the Construction Specifications for the reclamation work. This revision details the changes and modification to the QNQC testing program, as discussed with NRC staff, and modifies the nomenclature for the different reclamation layers.
- 3)
Revised Figure A-5. l-1, Reclamation Cover Grading Plan, adding cross section locations for the breach of Cell 4A Dike.
Mr. N. King Stablein April 15, 1999 Page 2 of2
- 4)
Sections D and E to Figure A-5.1-1, details the cross sections to the breach of Cell 4A Dike.
- 5)
Revised Rational Methc.,J Calculation of PMF Peak Discharge, Velocity, Depth, and Scour thrcugh Cell 4A Breach, with breach widened to 200 feet.
- 6)
Revised details to the Rock Apron at Toe of Cell Outslope. This drawing has been previously submitted to the NRC in response to Question 19 of the August 28, 1998 Submittal to NRC.
- 7)
Results of a rerun of the Radon Emanation Calculations to take into account revisions to inconsistent variables and more conservative approach to the assumptions used in cover design, as per NRC staff suggestions, As mentioned earlier, additional responses wiIJ be submitted to NRC under separate cover.
HRR:pl Enclosures cc: William N. Deal David C. Frydenlund Robert A. Hembree Earl E. Hoellen Michelle R. Rehmann Central Files Very truly yours,
~.--C/ p1 /?--
'7},f,1/,-e.-e_
Harold R. Roberts Executive Vice President
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Soil Sampling and Testing Program - White Mesa Mill The purpose of this Soil Sampling and Testing Program is to verify the soil classification.
gradation and compaction characteristics (standard proctor) of the stockpiled random fill and clay materials that will be used for cover materials on the tailings cells at the White Mesa Mill.
Additionally this program will verify the compaction characteristics and gradation of the random fill materials utilized in the platform fill previously placed on Cells 2 and 3.
Sampling Sampling will take place on each of six stockpiles of random fill ( designated RF-I through RF-6 on Exhibit A). two clay material stockpiles (C-1 and C-2 on Exhibit A). and on platform fill areas in Cells 2 & 3. A total of 9 samples will be taken from the random fill stockpiles. Two ( 2) samples will be taken from the clay stockpiles and three (3) samples will be taken from the covered areas of the cells. Samples will be taken from test pits excavated by a backhoe. Samples will be taken from a depth of 8 feet in stockpiles and from 2 foot depth in cells. One backhoe bucket full of material will be taken from the test pit at the specified depth and dumped separately. This sample will be quartered and one quarter will be screened to minus 2" (rocks over s** will be removed prior to screening). Two five gallon sample buckets will be filled with sample randomly selected from the screened fraction. Oversized material remaining after the screening of the sample will be visually classified and then weighed.
Sample locations will be indicated on a site map and sample descriptions will recorded and maintained in the facility's records. A total of fourteen samples will be submitted for testing during this program.
Testing Samples will be packaged and shipped to a certified commercial testing laboratory for testing.
Tests will be run on each sample for standard proctor (ASTM D698). particle size analysis (ASTM Cl 17 and ASTM Cl36), soil classification (ASTM 02487) and plasticity index (Atterberg limits ASTM 043 l 8).
SOILTEST.IXX.:/ 04/14/99/2:50 PM
DOCUMENT PAGE(S) PULLED SEE APERTURE CARD FILES.
APERTURE CARO/PAPER COPY AVAILABLE THROUGH NRC FILE CENTER NUMBER OF OVERSIZE PAGES FILMED ON APERTURE CARD/SJ I
ACCESSION NUMBERS OF OVERSIZE PAGES:
99dt/~251-d ---
PLANS AND SPECIFICATIONS FOR RECLAMATION OF WHITE MESA FACILITIES BLANDfNG. lJTAH PREPARED BY INTERNATIONAL URANIUM (USA) CORP.
INDEPENDENCE PLAZA SLTfE 950. 1050 l 7rn STREET DENVER, CO 80265
\\USERS\\WMREPLANiRECLAM_WM 961FNLDRAff'.AlTA,M11ch ?<J I~
ATTACHMENT A
1.0 2.0 3.0 4.0 5.0 Page :\\-1 Re\\ is1u,1 I 0 International l'ranium I USA) Corp White Mesa Mill Redamation Plan
("ABLE OF CONTENTS GENERAL.................
CELL l-1 RECLAMATION...
2.1 Scope............................
Removal of Contaminated Materials...
2.2.1 2.2.2 2.2.3 2.2.4 Raffinate Crystals...........................
Synthetic Liner............
Contaminated Soils..............
Sedimentation Basin........
MILL DECOMMISSIONING.............
3.1 3.2 3.3 Mill....................................................
Mill Site.............................
Windblown Contamination.......................
3.3. l Guidance...................
- 3. 3. 2 General Methodology....
3.3.3 Scoping Survey..............
3.14 Characterization and Remediation Control Surveys 3.3.5 Final Survey...............
PLACEMENT METHODS..............
- 1.1 Scrap and Debris................
4.2 Contaminated Soils and Ratlinate Crystals.
4.3 Compaction Requirements.................
CELLS 2.AND 3........................
5.1 Earth Cover..........................
Page No.
A-1 A-I A-I A-I A-1 A-.2 A-2 A-3 A-5 A-5 A-7 A-7 A-9 A--9 A-10 A-11 A-11 A-14 A-14 A-15 A-15 A-16 A-16
6.0 Page :\\*11 Re\\ ision I O International l 'ranium ( l :sA J (\\1rp Whitt' :Vksa Mill Rcdamatiun Plan TABLE OF CONTEN f'S (continued) 5.2 5.3 5.4 Materials 5.2. l Physical Properties.
5.2.2 Borrow Sources Cover Construction 5.3. l General.
5.32 Placement and Compaction 5.3.2 I Methods 5.3.2.2 Moisture and Density Control Monitorini (\\1\\er Settlement 5.4 I T empurary Settlement Plates
- 5. -U. I Gencrnl
.'.1i.4.l.2 lnstaHation 5 4. I J Monitoring Setth.!ment Plates ROCK PR<.HH. 'lfON 61 General 6.2 Materials 6.3 Placement Page Nu A.-lh
.\\.18 A-18 A-18
\\-18 A 18 A 20 A*.:1
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<)I,\\I I I Y ( 'Ol\\ I ROI <)l :\\I I IY ASSl RANCI*
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1.0 OFNERAI.
l'.t~r..* \\... I R\\.'\\ IShlll I 0 International l ram um ( l S:\\ 1 < '11rr White ~h.*sa Mill Rcdamahnn Pla11 l'he specitkations presented in this section cover the reclamation of the White Mesa ~111l fai.:1l1t1c, 2.0 CELL 1-l RE< 'I.AMA J'ION 2.1
~"*
l'he reclamation t)f ( 'ell 1-1 i.::onsists of evaporaUnij the.> cdl to dryness, removmi ndlit1att: cn st.ih.
syntheti4.* hncr and an.> contaminated soils *\\ -;edtmt'ntatiun basin will then ht* t'.onstnu.:lltJ.. md a drainawe channtl pruv1dci:d Raffinal1l crystals wdl ht-remon:d trom ( 'till I *1 and transported to the tmhn¥s ndls h 1s ant1npatt.~d that th~.,:rystaJs wlll havii' a conststenq smuiar hi a jUmular matcmal wh,n hrou11ht to th.: ~.ttlb "'uh larai.: cry,tal fl\\Wlses bemg broken Jown for* transport Piacernent nt th~ 1.:r) stals will ht-J'4i'rtorm'1d as a 1n111ul11 fill. wtth ~are bem1 tak@n to a\\oiJ nestm1 of hujc> sw:J mat~rnli \\ thJr.i a.round latW,t' mak'ntlt wHI be filled with tlner mattnat l){ thtt ny1tal m~~ brnk(n Juwn h; thi!' pl&.mt.t tt~u1pnh:m A\\:'.h.1.aJ pla..;1me11:t Pfill.'@dures wm be ~viilwtcd h) tht: <.)(
- l>t'tku Junnt1t i.:onstrndmn,ts u, "ta!
materu1ls are bio\\&lht Md pltwtd 111 &ht (~Us
2.2.2 Synt:hetic Liner Paijt:,\\-~
Revisil.)n I 0 International l 1ranium (USA) Corp White Mesa Mill Reclamation Plan l'he PVC hner witJ be cut up, folded (when n.ecessary ), removed from Cell 1 *Land transrort~d to the tailinjs cells. The hner material will be spread as tlat as pructicaJ over tht desit4nate<l area. i\\ her-phwement, the lin~r will be covered as 100n as possible with at leasl one foot of soil, cry stats or otht>r materials for protection a1ainst wiml as approv~d hy the(}(* oftker.
2 2J Contaminated Soils f"ht extent of contammat1011 of the mm site will be detemuned by a s1.:mtillometer survey It ne.;esury. a,om;,huwn between scintitlorneter readings Qlld U -nat1Rad1um-226 c{nu.:entratwns will be dcvclop,d Sdntdf.,rn+1ter readin1s ~an then be used to define chmnup arias anJ to momtor thtt dtaru~p Soil swnphn11 will be conducted to confirm that lhe deanup rtisuhl'! in a 1.:om.::~ntratwn ol Radium-226 a\\iora,ttd over any area of IO() square meters that docs not excetd dw ~kt,Jrow1d level by mort than.
5 p( *v ¥ averaaed over the first I 5 i;:m of sods belo" dw isurta<:e, and I 5 p( 'i11 aver1i11-ed ov,r i 15 cm th1~k lay fr of soils more than 15 l:Ol betov. the surial'.e Where survt) i U'lOl\\!itt the ~vc critvna bilve not been il\\£h1cved. dw soil w*ll ht Nmovtd to m<<11~t dw cn~r,a. Sutl removtd tr.;>>11 Celt I *1 will be,~,;111vaicd aru;J triU\\lf)OJ1eJ to ttw buhti\\Ms ~*~lls t*t-.:enwut ul4 c~hon wm be m 14,:co,..,,u,, w t.-.h ~f!iUon 4 _ 0 (.)f *~- PIW\\-il tll'ta s,-~ ttkuuun.:.
2 2 A Sedimentation Basin Pagt'. \\.,
Revision I O lnte, national l 'rnnium (I 'SA) Corp White Mesa Mill Rc1..:lam,ttio11 Plan Cell 1-l will then~ breached anti constmdcd as a sedimentation hasm All runoff from the null area anJ immeJ1atcl} north dfthe i..:dl will be n11Jted mto £he sed1mt:'ntat.*,1n hasm and v.ill J1s1..:hargt:
onto the natural ground via the 1.:harnel locar~d at the southv.est cumer ot the basin I he channel 1s desijncd tn ac,ommodate the PMr flood A :icdmumtallon basin will rn: construi..'.ted 1 "i ( 'ell l.f.. b shov..n in t* 1~un: A2 2 -.l-1 Uradmg v.111 he performed to promote draim1ait~ and proper fonl:t10nin~ ofthr-hasm I he Jramajc 1..':hanncl uut ut the ied1mentation hasm will he nmstrw.:ted t.o the 1111e;; a id ~rades as shown
Pagl'.\\--1, RI.'\\ is ion I 0 International 1 'ramum (l 'SA) C1.>rp.
\\Vhitc Mesa Mill Redamation Plan INSU{ I Fl(il :RF A-2.2.*~-I SF DI Ml NI.\\ !ION BASIN l>LTAll.S
3.0 MILL DECOMMISSIONING Page A-5 Revision 1.0 International Uranium ( USA) Corp.
White Mesa Mill Reclamation Plan The following subsections detail decommissioning plans for the mill buildings and equipment: the mill site; and windblown contamination.
3.1 Mill The uranium and vanadium processing areas of the mill. including all equipment, structures and support facilities. will be decommissioned and disposed of in tailings or buried on site as appropriate. All equipment. including tankage and piping, agitation equipment, process control instrumentation and switchgear, and contaminated structures will be cut up, removed and buried in tailings prior to final cover placement. Concrete structures and foundations will be demolished and removed or covered with soil as appropriate. These decommissioned areas would include. but not be limited to the following:
Coarse ore bin and associated equipment, conveyors and structures.
Grind circuit including semi-autogeneous grind (SAG) mill, screens, pumps and cyclones.
The three preleach tanks to the east of the mill building, including all tankage.
agitation equipment, pumps and piping.
The seven leach tanks inside the main mill building, including all agitation equipment, pumps and piping.
The coumer-current decantation ( CCD) circuit including all thickeners and equipment, pumps ano piping.
Uraniwn precipitation circuit. including all thkkeners. pumps and piping.
il/SERS'W'vlREPLAN\\RECLAM,WM l,l61FNLl>RAFT,A !"IA Man:h 29. 1999
Page."\\-6 Re\\ision 1.0 International Uranium ( USA) Corp.
White Mesa Mill Reclamation Plan The two yellow cake dryers and all mechanical and electrical support equipment.
including uranium packaging equipment.
The clarifiers to the west of the mill building including the pre leach thickener ( PLT) and claricone.
The boiler and all ancillary equipment and buildings.
The entire vanadium precipitation. drying and fusion circuit.
All external tankage not included in the previous list including reagent tanks for the storage of acid. ammonia. kerosene, water, dry chemicals. etc. and the vanadium oxidation circuit.
The uranium and vanadium solvent extraction (SX) circuit including all SX and reagent tankage, mixers and settlers. pumps and piping.
The SX building.
The mill building.
The office building.
The shop and warehouse building.
The sample plant building.
The sequence of demolition would proceed so as to allow the maximum use of support areas of the facility such as the office and shop areas. It is anticipated that all major structures and large c:quipment will be demolished with the use of hydraulic shears. These will speed the process.
provide proper sizing of the materials to be placed in tailings, and reduce exposure to radiation and other safety hazards during the demolition. Any uncontaminated or decontaminated equipment to be considered for salvage will be released in accordance with the tenns of License Condition 14.
As with the equipment for disposal, any contaminated soils from the mill area will be disposed of in the tailings facilities in accordance with Section 4.0 of the Specifications.
\\USERS\\WMREPLAN\\RECLAM~iM 96\\FNLDRAFT\\ATTA\\March 29. 1999
3.2 Mill Site Page :\\-7 Revision 1.0 International Uranium ( USA) Corp.
White Mesa Mill Reclamation Plan Contaminated areas on the mill site will be primarily superficial and include the ore storage area and surface contamination of some roads. All ore will have been previously removed from the ore stockpile area. All contaminated materials will be excavated and be disposed in one of the tailings cells in accordance with Section 4.0 of these Plans and Specifications. The depth of excavation will vary depending on the extent of contamination and will be based on the criteria in Section 2.2.3 of these Plans and Specifications.
All ancillary contaminated materials including pipelines will be removed and will be disposed of by disposal in the tailing cells in accordance with Section 4.0 of these Plans and Specifications.
Disturbed areas will be covered, graded and vegetated as required. The proposed grading plan for the mill site and ancillary areas is shown on Figure 3.2-l.
3.3 Windblown Contamination Windblown contamination is defined as mill derived contaminants dispersed by the wind to surrounding areas. The potential areas affected by windblown contamination will be surveyed using scintillometers taking into account historical operational data from the Semi-annual Effluent Reports (Appendix A) and other guidance such as prevailing wind direction and historical background data.
1USERS\\WMREPLAN\\RECLA~M 96\\FNLDRAFP.ATTA,Mari:h 29. 1999
INSERT FIGURE A3.2-I Page :\\-8 Revision I.0 International Uranium (USA) Cnrp.
\\Vhite Mesa Mill Reclamation Plan MILL SITE AND ORE PAD FINAL GRADING PLAN 1USERS\\WMREl'LAN\\RECLAM~M 96\\FNLDRAFTI.ATI \\ 1~1Mch 29. 1999
3.3. l Guidance Pag~ A-4 Revision 1.0 International Uranium ( USA) Corp.
Whitt: Mesa Mill Reclamation Plan The necessity for remedial acti,ms will be based upon an evaluation prepared by IUC, and approved by the NRC, of the potential health hazard presented by any windblown materials identified. The assessment will be based upon analysis of all pertinent radiometric and past land use information and will consider the feasibility. cost-effectiveness, and environmental impact of the proposed remedial activities and final land use. All methods utilized will be consistent with the guidance rontained in NUREG-5849: "Manual for Conducting Radiological Surveys in Support of License Termination."
3.3.2 General Methodology The facility currently monitors soils for the presence of Ra-226, such results being presented in the second semi-annual effluent report for each year. Guideline values for these two materials will be determined and will form the basis for the cleanup of the White Mesa Mill site and surrounding areas. For purposes of determining possible windblown contamination, areas used for processing of uranium ores as well as the tailings and evaporative facilities will be exduded from the initial scoping survey. due to their proximity to the uranium recovery operations. Those areas include:
The mill building. including CCD. PL T area, uranium drying and packaging.
clarifying, and preleach.
The SX building, including reagent storage immediately to the east of the SX building.
The ore pad and ore feed areas.
Tailings Cells No. 2, 3. and 4A.
Evaporative cell No. 1-1.
,USERS\\WMRi:PLAN\\RECLAM.WM Q61FNLDRAFTATTA,March 29. 1999
Page A-10 Re\\'ision 1.0 International Uranium (US:-\\) Corp.
White Mesa Mill Reclamation Plan The remaining areas of the mill will be divided up into two areas for purposes of windblown determir.ations:
The restricted area, less the abow areas; and, A halo around the restricted area.
The restricted area. as shown on Figure A3.2-I will be initially surveyed on a 30 x 30 meter grid as described below in Section 3.3.3. The halo around the restricted area will also be initially surveyed on a 50 x 50 meter grid using methodologies described below in Section 3.3.3. Any areas which are found to have elevated activity levels will be further evaluated as described in Sections 3.3.4 and 3.3.5.
3.3.3 Scoping Survey The scoping survey will be conducted using a calibrated Mount Sopris Model SC-132 scintillometer (or equivalent) capable of detecting radiation at levels less than or equal to 25 percent of the guideline value. The meter will be swung from side to side at an elevation of six ( 6) inches above th-: ground level while walking a path within the grid shown in Figure A-3.3-1. These paths wiH be designed so that a minimum of IO percent of the area within the grid sidelines will be scanned. using an average coverage area for the scintillometer of one (I) meter wide. Grids where hotspots are encountered or where readings of 75 percent of the guideline level are found will be reclassified as affected areas, and will be subject to further characterization as described below. Grids where no readings exceea 75 percent of the guideline value will be classified as unaffected, and therefore will not require remediation. It is assumed that by following methodologies that would be utilized during the final survey, that the classification of these areas would stand and would require no further survey confirmation.
\\USERS\\WMREPLAN\\RECLAM.WM 96\\FNLDRAFT\\Afl'A\\Ma,ch 29. 1999
Page A-1 l Revision 1.0 International Uranium (USA) Corp.
White Mesa Mill Reclamation Plan A sufficient quantity of QA samples will be taken to provide a correlation between the meter readings and the actual Ra-226 concentrations in the soil.
3.3.4 Characterization and Remediation Control Surveys After the entire subarea has been classified as affected or unaffected. the affected areas will be further scanned to identify areas of elevated activity requiring cleanup. Such areas will be tlagged and sufficient soils removed to, at a minimum, meet activity aiteria. Following such remediation.
the area will be scanned again to ensure compliance with activity criteria. A calibrated Mount Sopris SC-132 scintillometer ( or equivalent ) capable of detecting activity levels of less than or equal to 25 percent of the guideline values will be used to scan all the areas of interest.
3.3.5 Final Survey After remediation. the affected areas deemed to be in compliance with standards will then undergo a final survey, t.ailizing a IO x IO meter grid system with sample point locations as shown in Figure A-3.3-2. Again a calibrated Mount Sopris SC-132 scintillometer (or equivalent) capable of detecting activity levels of less than or equal to 25 percent of the guideline values will be used. and will be held at a one meter distance above the systematic sample locations. As with the scoping survey, a statistically significant quantity of QA samples will be taken at randomly selected points to provide a correlation between the meter readings and the actual Ra-226 concentrations in the soil.
USERS\\ WMREPLAN.,RECLAMWM 961FNLDRAFTAfT A,March 29. 1999
Figure A3.J-I
\\lJSERS\\WMREPLAN\\RECl.AM,.WM 96\\fNLDRAFTiAn A1March 29. 1999 Page: :\\-1~
Re\\ision I O International Uranium ( LSA I Corp.
White Mesa Mill Reclamation Plan
Figure A3.3-2
- .USERS\\WMREPLAN\\RECLAM,WM 96\\fNLDRAFl'v\\ITA,March 29. 1999 Pagt: A-1:,
Revision 1.0 International Uranium ( USA) Corp.
White Mesa Mill Reclamation Plan
4.0 4.1 PLACEMENT METHODS Scrap and Debris Page.\\-1..J Re,ision 1.0 International L'ranium ( L'Sr\\ I Corp.
White Mesa ~1ill Reclamation Plan The scrap and debris will have a maximum dimension of 20 feet and a maximum volume of 30 cubic feet. Scrap exceeding these limits will be reduced to within the acceptable limits by breaking.
cutting or other approved methods. Empty drums, tanks or other objects having a hollow volume greater than five cubic feet will be reduced in volume by at least 70 percent. If volume reduction is not teasible. openings will be made in the object to allow soils, tailings and/or other approved materials to enter the olject at the time of covering on the tailings cells. The scrap, after having been reduced in dimension and volume, if required, will be placed on the tailings cells as directed by the QC officer.
Any scrap placed will be spread across the top of the tailings cells to avoid nesting and to reduce the volume of voids present in the disposed mass. Stockpiled soils, contaminated soils, tailings and/or other approved materials will be placed over and into the scrap in sufficient amount to fill the voids between the large pieces and the volume within the hollow pieces to form a coherent mass. It is recognized that some voids will remain because of the scrap volume reduction specified, and because of practical limitations of these procedures. Reasonable effort will be made to fill the voids. The approval of the Site Manager or a designated representative will be required for the use of materials other than stockpiled soils, contaminated soils or tailings for the purpose of filling voids.
\\lJSERS\\WMREPLAN\\RECLAMWM %\\FNLDRAFTi.ATTA1March 29. 1999
4.2 Contaminated Soils and Raffinate Crystals Page A-15 Rc\\isinn 1.0 International Uranium ( l '.SA) Corp.
White Mesa !\\'till Reclamation Plan The various materials will not be concentrated in thick deposits on top of the tailings. but \\\\ill he spread over the working surface as much as possible to provide relatively uniform settlement and consolidation characteristics of the cleanup materials.
4.3 Compaction Requirements The scrap. contaminated soils and other materials for the first lift will be placed over the existing tailings surface to a depth of up to four feet thick in a bridging lift to allow access for placing and compacting equipment. The first lift will be compacted by the tracking of heavy equipment, such as a Caterpillar 06 Dozer (or equivalent), at least four times prior to the placement of a subsequent lift. Subsequent layers will not exceed two feet and will be compacted to the same requirements.
During construction. the compaction requirements for the crystals will be reevaluated based on field conditions and modified by the Site Manager or a designated representative. with the agreement nf the NRC Project Manager.
The contaminated soils and other cleanup materials after the bridging lift will be compacted to at least 80 percent of standard Proctor maximum density (ASTM D-698).
USERS\\ WMREPLAN\\RECLAM.WM %1FNl.DRAFT-A rT A,Man:h 29. I <<m
5.0 CELLS 2,AND ]
Page A-16 Revision 1.0 International Uranium (USA) Corp.
White Mesa Mill Reclamation Plan A mulu-layered earthen cover will be placed over tailings Cells 2. Allil 3. The general grading plan is shown on Drawing 5. 1-1. Reclamation cover cross-sections are shown on Drawings 5. l -2 and 5. 1-J.
5.2 I Physical Properties l'he physical properties of materials for use as cover soils will meet the following:
Hlfliom fill (Platform Fill and f'rost Barrier) rhese materials will be mixtures of clayey sands and silts with random amounts of gravel and rock size materiaJ. In the initial bridging lift of the platfonn fill. rock sizes of up to_2/3 of the thickness of the lift will be allowed. On all other random fill lifts, rock sizes will be limited to 2/3 of the lift thickness. with at least 30 percent of the material finer than 40 sei ve. For that portion passing the No. 40 sieve. the$e soils will classify as CL, SC. MC or SM materials under the Unified Soil Clusitkation System. Oversized material will be controled through selective excavation at the st~kpUes and chrou,h the utihz.ation of a grader. bulldozer or backhoe to cull oversize from the fill.
<JulatsW.i&lf Cl*Y* will have 1t lqat 40 percent pusina the No. 200 sieve. The minimum liquid limit of these soUs will be 25 Md the plasti~ity index wilJ be I 5 or areater. These soils will classify as CL. SC or CH malffltis tiWttr ow Unified Soil ClassUkation System.
AS.I-I Page.*\\-1 7 Revision l 0 International l.1ranium (L:SA) Corp.
White ~1esa Mill Redamation Plan
5.2.2 Borrow Sources The sources for soils for the cover materials are as follows:
Page :\\-18 Revision 1.0 International Uranium ( USA) Corp.
White Mesa Mill Reclamation Plan I.
Random Fill {Platform and Frost BarrierJ - stockpiles from previous cell construction activities currently located to the east and west of the tailing facilities.
- 2.
Clay - will be from suitable materials stockpiled on site during cell construction or will be imported from borrow areas located in Section 16, T38S. R22E. SLM.
- 3.
Rock Armor - will be produced through screening of alluvial gravels located in deposits I mile north of Blanding,Uath, 7 miles north of the mill site.
5.3 Cover Construction 5.3. l General Placement of cover materials will be based on a schedule determined by analysis of settlement data.
piezometer data and equipment mobility considerations. Settlement plates and piezometers wi II be installed and monitored in accordance with Section 5.4 of these Plans and Specifications.
5.3.2 Placement and Compaction 5.3.2. I Methods Platform Fill An initial lift of 3 to 4 feet of random fill will be placed over the tailings surface to form a stable working platfonn for subsequent controlled fill placement. This initial lift will be placed by pushing random fill material or contaminated materials across the tailings in increments. slowly enough that
Page A-19 Revision I. O International Uranium (CSA) Corp.
White Mesa Mill Reclamation Plan the underlying tailings are displaced as little as possible. Compaction of the initial lift will be limited to what the weight of the placement equipment provides. The maximum rock size. as far as practicable. in the initial lift is 2/3 of the lift thickness. Placement of fill will be monitored by a qualified individual with the authority to stop work and reject material being placed. The top surface (top l.O feet) of the platform fill will be compacted to 90% maximum dry density per ASTM D 698.
Frost Barrier Fill Frost barrier fill will be placed above the clay cover in 12-inch lifts, with particle size limited to 2/3 of the lift thickness. Frost barrier 1.1aterial will come from the excavation ofrandom fill stockpiles.
If oversized material is observed during the excavation of fill material it will be removed as far as practicable before it is placed in the fill.
In all layers of the cover the distribution and gradation of the materials throughout each fill layer will be such that the fill will, as far as practicable, be free of lenses. pockets, streaks or layers of material differing substantially in texture, gradation or moisture content from the surrounding material. Nesting of oversized material will be controled through selective excavation of stockpiled material. observation of placement by a qualified individual with authority to stop work and reject material being placed and by culling oversized material from the fill utilizing a grader. Successive loads of material will be placed on the fill so as to produce the best practical distribution of material.
If the compacted surface of any layer of fill is too dry or smooth to bond properly with the layer of material to be plar.ed thereon, it will be moistened and/or reworked with a harrow. scarifier. or other suitable equipment to a sufficient depth to provide relatively uniform moisture content and a satisfactory bonding surface before the next succeeding layerofearthfill is placed. If the compacted surface of any layer of earthfill in-place is too wet, due to precipitation, for proper compaction of the earthfill material to be placed thereon, it will be reworked with harrow. scarifier or other suitable
Page.\\-20 Re\\ ision 1.0 International Uranium (USA) Corp.
\\Vhite Mesa Mill Reclamation Plan equipment to reduce the moisture content to the required level shown in Table 5.3.2. l-l. It will then be recompacted to the earthfill requirements.
No material will be placed when either the materials, or the underlying material. is frozen or when ambient temperatures do not permit the placement or compaction of the materials to the specified density. without developing frost lenses in the fill.
5.3.2.2 Moisture and Density Control As tar as practicable, the materials will be brought to the proper moisture content before placement on tailings, or moisture will be added to the material by sprinkling on the earthfill. Each layer of the fill will be conditioned so that the moisture content is uniform throughout the layer prior to and during compaction. The moisture content of the compacted fill will be within the limits of stand*trd optimum moisture content as shown in Table 5.3.2.1-1. Material that is too dry or too wet to pem1it bonding of layers during compaction will be rejected and will be reworked until the moisture content is within the specified limits. Reworking may include removal. re-harrowing. reconditioning.
rerolling, or combinations of these procedures.
Density control of compacted soil will be such that the compacted material represented by samples having a dry density less than the values shown in Table 5.3.2. l-I will be rejected. Such rejected material will be reworked as necessary and rerolled until a dry density equal to or greater than the percent of its standard Proctor maximum density shown in Table 5. 3. 2. 1-1.
To determine that the moisture content and dry density requirements of the compacted fill are being met. field and laboratory tests will be made at specified intervals taken from the compacted fills as specified in Section 7.4, "Frequency of Quality Control Tests."
5.4 MoQitodoi cover s,uiemeot
5.4. l Temporwy Settlement Plates 5.4.1. l General Page A-21 Revision 1.0 International Uranium (ljSA) Corp.
White Mesa Mill Reclamation Plan Temporary settlement plates will be installed in the tailings Cells. At the time of cell closure, a monitoring program will be proposed to the NRC.
Data collected will be analyzed and the reclamation techniques and schedule adjusted accordingly.
5.4.1.2 Installation At the time of cell closure or during the placement of interim cover temporary settlement plates will be installed. These temporary settlement plates will consist of a corrosion resistant steel plate 1 I 4 inch thick and two foot square to which a one inch diameter corrosion resistant monitor pipe has been welded. The one inch monitor pipe will be surrounded by a three inch diameter guard pipt:
which will not be attached to the base plate.
The installation will consist of leveling an area on the existing surface of the tailings. and placing the base plate directly on the tailings. A minimum three feet of initial soil or tailings cover will be placed on the base plate for a minimum radial distance of five feet from the pipe.
5.4. l.3 Monitoring Settlement Plates Monitoring of settlement plates will be in accordance with the program submitted to and approved by the NRC. Settlement observations will be made in accordance with Quality Control Procedure QC-16-WM, "Monitoring of Temporary Settlement Plates."
INSERT TABLE 5.3.2.1-1 1USERS\\WMREPLAN\\RH'LAMWM 96'.FNLDRAfT\\ATTA'.March 29. 1999 Page A-22 Rc\\'ision 1.0 International Uranium I USA) Corp.
White Mesa Mill Redamation Plan
6.0 ROCK PROTECTION 6.1 General Page A-23 Revision 1.0 International Uranium ( GSA) Corp.
White Mesa Mill Reclamation Plan The side slopes of the reclaimed cover wiJI be protected by rock surfacing. Drawings 5. l -1. 5.1-2.
and 5.1-3 show the location of rock protection with the size. thickness and gradation requirements for the various side slopes.
A riprap layer was designed for erosion protection of the tailings soil cover. According to NRC guidance, the design must be adequate to protect the soil/tailings against exposure and erosion for 200 to 1.000 years (NRC. 1990). Currently, there is no standard industry practice for stabilizing tailings for 1,000 years. However. by treating the embankment slopes as wide channels. the hydraulic design principles and practices associated with charmel design were used to design stable slopes that will not erode. Thus, a conservative design based on NRC guidelines was devdoped.
Engineering details and calculations are summarized in the Tailings Cover Design report (Appendix D).
Riprap cover specifications for the top and side slopes were determined separately as the side slopes are much steeper than the slope of the top of the cover. The size and thickness of the riprap on the top of the cover was calculated using the Safety Factor Method (NUREG/CR-465 J. J 987). while the Stephenson Method (NUREG/CR-4651. 1987) was used for the side slopes. These methodologies were chosen based on NRC recommendations ( 1990).
By the Safety Factor Method, riprap dimensions for the top slope were calculated in order to achieve a slope "safety factor" of 1.1. For the top of the soil cover, with a slope of 0.2 percent, the Safety Factor Method indicated a median diameter(D~0) riprapof0.28 inches is re\\.fuired to stabilize the top slope. Howcv-:r, this dimension must be modified based on the long-term durability of the specific rock type to be used in *construction. The suitability of rock to be used as a protective cover must 1USERS\\WMREPLAN\\Jl.ECLAMWM 96ifNLOllAf'J',A lTA\\March 29. 1999
Page :-\\-2-t Revision 1.0 International Uranium ( USA) Corp.
White Mesa Mill Reclamation Plan be assessed by laboratory tests to determine the physical characteristics of the rocks. The gravels
-;ourced from pits located north of Blanding require an oversizing factor of9.35%. Therefore. riprap created from this source should have a 0 50 size of at least 0.306 inches and should have an overall layer thickness of at least three inches on the top of the cover. From a practical construction standpoint the minimum roi:k layer thickness may be up to six ( 6) inches.
Riprap dimensions for the side slopes were calculated using Stephenson Method equations. The side slopes of the cover are designed at 5H: l V. At this slope, Stephenson's Method indicated the unmodified riprap 0 50 of 3.24 inches is required. Again assuming that the gravel from north of Blanding will be used, the modified 0 50 size of the riprap should be at least 3.54 inches with an overall layer thickness of at least 8 inches.
6.2 Materials Materials utilized for riprap applications will meet the following specifications:
Location 0 50 Size D 1(k> Size Layer Thickness Top Surface OJ" 0.6" 6"
Slope Surface 3.5" 7"
8" Toe Apron 6.4" 12" 24" Riprap will be supplied to the proje,t from gravel sources located north of the project site. Riprap will be a screened product.
1USEiRS\\WMREPLAN\\RECLAMWM.%\\FNI.PRAff1An A\\Mweh 19. 1999
Page..-\\-.25 Revision 1.0 International Uranium (L'SA) Corp.
White Mesa Mill Reclamation Plan Riprap quality will be evaluated by methods presented in NUREGi 1623 Design of Erosion Protection for Long-Term Stabilization Sile adjustment will be made in the riprap for materials nol meeting the quality criteria.
6.3 Placement Riprap material will be hau?ed to the reclaimed surfaces and placed on the surfaces using belly dump highway trucks and road graders. Riprap will be dumped by trucks in windrows and the grader will spread the riprap in a manner to minimize segregation of the material. Depth of placement \\.\\ ill b~
controled through the establishment of grade stakes placed on a 200 x 200 foot grid on the top of the cells and by a J 00 x l 00 foot grid on the cell slopes. Physical checks of riprap depth will be accomplished through the use of hand dug test pits at the center of each grid in addition to monitormg the deptl* indicated on the grade stakes. Placement of the riprap will avoid accumulation of riprap sizes less than the minimum Diu size and nesting of the larger sized rock. The riprap layt:r will be compacted by at least two passes by a D-7 Dozer ( or equivalent) in order to key the rock ti.H stability.
7.0 QUALITY CONTROL/QlJAl.ITY ASSURANCE
- 7. 1 OY&lily Plan A Quality Plan has been developed for construction activities for the White Mesa Project. Th~
Quality Plan includes the fol!owing:
I.
QC /QA Deilmtions, Metbodolo>>y and Activities.
- 2.
Orglfti1.1tionaJ Structure.
- 3.
Surveys, lna~eions, SampUna and Tcstina.
- 4.
CMnps Md Ci\\ne.;tive Aclions.
- 5.
- 6.
7.2 Documentation Requirements.
Quality Control Procedures.
lmJ2u;wntati9n Page A-~6 Rc,iswn I 0 International Uranium I USAi Corp White Mesa Mill Reclamation Plan The Quality Plan will be implemented upon initiation of reclamation work.
Quality control procedures have been developed for reclamation and are presented in Attachment B of this Reclamation Plan. Procedures will be used for all t~stinv. sampling and im;pection functions.
The frequency of the quality control tests for earthwork will. be as tollows
- l.
The frequency of the field density and moisture tests will be not less than one test per t.000 cubic yards (CY) ot* compacted contaminated material p1a£ed and one teit per.500 CY of compacted rlftdom tUI, radon bttrier or froit btrri*.u. A minimum of two tests wtli bt.;: t~en for eaeh day tMt an ilPfllkabJe amoWit of fitt is pi.aced in ijXCeSfi of l 50 (' Y A minimun1 u t one *** per lift Mid at leaat one ttit for evtry tull shit\\ of COfflPtition up,rat*~ w1U be f'..W._l)'lmoittw* tt** will *.-,tof'Q'Md \\ltihzin1 a ~If* ***Y IINI' U\\ilM I)..
2ti2 -~ -, AITM 0-JOl 7 fflOi..,. '°'*ffl). Con,lation lfltl will IN ~d OM,. O\\'t,)' Iv* --........ tw com,wtn '1~-...... {OIW
Paai~ A-.:!7 Re,isu>n 1.0 lnttmational L'raruum tUSAl Corp Whttr Mesa Mill Redamauon f>lan per 2.500 CY pl*td) and one for every ten nuclear 1auge tests for other compac:teJ mat.rriais (one P4tr 5,000 CY of material placed). Correlation tests will bt! sand cone tests (AS( MD-I S56) for c;t.nsity determination Md oven dryin1 m.:thoJ (ASTM D*22 l6) ti,r moistuH detennination.
- 2.
Gradation and cla**:,1fkahon test1n1 will be performed at a minimum of one test p¢r 1,000< *y of upper pJatform fill and frost barrier placed. A minimum of ont kit will be s-rformed for ea..:h 1,000 CY of radon harrier material placed. For aU mat~rials oth~r than randorn fill and contaminated ru.aterials. at leut one 1rNation ttst will be run for ta..ih IU} of 111.rufkant
,mutria,I phttemem ( in excess of 150 CY)
- 3.
Atterber1 hmlts will be determined Ott materials NlJil plaeed u radon banic,r. Radon bartl¢r malfftal wm be tested at a rak' of at least once each day of sitnitkarit material p!i!Wement ( m
@)(ttH of I 50 CY). Stmptcs should he rNldomly Ukrckld
- 4.
Prior to lh# st.Vt <:1:f thdd co~tion operat10Aa. a,proptiat, lahoratof},t>>n~non i.:un~is wiH lwt obwrwd for the r-ae of lffltM1'14NS to at p!~ed Durin1 C011$~Uon.,:,iw pouu Prock.Jr tffti will be ptrl,:.mwd at a &tqw,n()' of OM lttt p,r @ve.ry n1.,, ti*ld dlnstt) ttuts (OM l4'lt,., 2.,00 CY pi*ed> Laioratot') CUfflf*;llOft 1,'.Uf\\fi o,~~ Oft t.:Oft\\plt}k: Proctor Wfll) Witt be ~- iM t hq'ltt¥:Y of.,,OXimaiel~ o,w ftlf fVff) IO to l '5 t\\t}d.lt&it)
Wlli t'fflt lab Pl'Oi!tor Wit,Wt S,000 CY to 7,SOO CY plMed),.poRG4hl t"1fl.. HtltiibtlU)
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- International Ura,u
.. 'um (USA) Corporation White Meea Mill MIi SHCET Y:
I of APP:
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l
Kaight Piesold Memorandum Date
.--\\pnl 15. ! 99 1)
To File 16268 From Roman Popielak and Pete Duryea Re Radon Emanation Calculations (Revised)
At the request of International Uranium (USA) Corporation ([UC), we have cunipleted a series of analyses of the expected levels of radon flux from the White r...lesa uranium tailings facility for the tailings cover design These analyses accounted for recent comments from the United States Nuclear Regulatory Commission (NRC)
Analysis Methodoloay and Input Parameters The analyses conducted and descnbed herein adopted the methods and approach detailed in NRC Regulatory Guide 3 6-t and more specifically the computer code RADON Version I 2 The code.
which considers one-dimensional steady state gas diffusion, requires input data including. layer thickness, porosity, dry density. radium activity, emanation coefficient, gravimetric water content and radon diffusion coefficient These input data were based exclusively on available data from previous \\vork by others including Rogers and Associates Engineering Corporation. Advanced Terr a Testing, Chen and Associates. D'Appolonia Consulting Engineers Inc and TIT A'.'4 Environmental Kev laboratory data and a summary of parameters selected for these analyses are presented in the attached Table 1 The current cover design includes 2 0 feet of random fill ( frost barrier fill) over I O foot of compacted clay which in turn overlies 3 0 feet of random fill (platform fill) ln the analyses. the thickness of final cover was reduced by 6 8 inches to I. 4 feet to account for the depth of frost penetration as evaluated by TIT AN Environmental The actual tailings thickness is on the order of 44 feet, which meets the NRC guidelines for an infinitely thick source, and hence it could be modeled in program RADON as a 500.0-centimeter thick layer Available data on the in-situ density of the tailing was used. All available historical Proctor compaction results for the other matenals were evaluated to select appropriate maximum dry densities for the clay and random fill The clay layer and frost barrier fill, which are to be placed and compacted as engineered till materials, were modeled with 95-percent standard Proctor compaction. The platform fill material is dumped and spread directly on top of the tailing surface. Once in place, the material is compacted by selective routing of equipment tratTtc, and it then provides a working surface for subsequent operations such as placement and compaction of the clay layer and frost barrier fill The compaction of material comprisina the platform is exp~cted to be higher at its top than at its contact with the tailings.
K.l!ight Piesold File 16268 April I -i. ! 11 1Jl)
Radon Emanation Calculations (Revised)
Within the platform fill, the surficial material is likely to exhibit fairly high compaction g1\\ en the influence of the contact stresses exerted by equipment tratfi: and later by the compaction of overlying material. Such stresses dimin:sh \\vith depth, so lower portions of the platform till will nut have experienced as significant a compactive effort. Compaction of the platform fill is therefGre likely to range from about 80-percent of standard Proctor at the base of the random fill 1mmed1ately above the tailing to 90- to 95-percent of standard Proctor compaction at the top of the platform fill immediately below the equipment loads just described The porosity of each of the materials/sublayers was calculated from its dry density and specific gravity of soil solids. Radium activities and emanation coefficients were selected for each soil type from available lab data, and the long term water contents "-vere selected for the anaiyses as follov.s.
ln the absence of other data, the tailing was modeled with a 6.0 percent by weight moisture content as the NRC recognizes 'that value as a practical lower bound for soils in the \\Vestern United States Long term moisture content can be conservatively modeled as the residual (or irreducible) water content from capillary moisture retention data since a lower value is more critical, that is it yields a higher radon tlux Such data was provided and used for the random fill and the clay The final, and one of the more critical parameters, was the radon diffusion coefficient. This parameter is dependent upor. the porosity and degree of saturation of the soil, and although lab data
\\vas available. it was for conditions other than those modeled So in the absence of diffibion coefticient data at the porosities and degrees of saturation of interest, a correlation provide by the
- "-iRC was employed to compute the ditfusion coetlicients adopted for the analyses These values ranged from O 0071 to 0.0507 cm~/sec It should be noted that the resultant values did seem to mat-:h
\\veil with the trends observed in the available laboratory data Results and Conclusions Since there were not data available describing the degree and distribution of compaction in the platform fill, a series of analyses were conducted based on varying assumptions about the condition of that material. ln each of those cases, the platform fill was divided into a series of sublayers whose thickness and degree of compaction were selected based upon engineering judgement and previous experience with similar situations The two caies of distribution of compaction considered to represent the conditions anticipated at White Mesa are presented in attached Figure l as Case I and Case II The results of the radon tlux evaluation for those two cases are attached For the reasonably conservative input parameters listed herein and an interim cover comprising 1 0 foot each at 80-, 90 and 95-percent compaction as shown as Case l in figure I, a radon flux at the ground surface of 18 2 pCilm2/sec is expected For Case 11 with O 5 foot of 95-percent compaction material overlying I O feet of 90-percent compaction material and I. 5 feet of 85-percent compaction material, the radon flux at the ground surface is 19 8 pCi/ml/sec. Both of these results are within the 20 0 p<=ilm /sec limit specified by the NRC
Knight Piesold File 16268 Radon Emanation Calculations ( Revised)
_)
April 15. 1999 Therefore, it appears that the cover design should be acceptable assuming that the cond1t1ons described herein do not vary significantly from those in the field In conclusion, empirical knowledge of the site conditions should be taken under consideration in evaluation of the model results. At present, approximately 80-percent of Cell No 2 is covered \\Vith the random fill (platform fill)
This fill supports traffic of the heavy, 30 ton haulers Hence the degree of compaction of the layer( s) as represented in the radon flux models ( see Figure I ) may have already been achieved in certain locations within the cell. The platform fill has been very effective to date in attenuating the radon flux, which as currently recorded is 7 4 pCi/m2/sec which is well below the standard of 20.0 pCi/m2/sec Based on these observations, it would appear that the performance of the tailings cover, which witl ultimately include the clay layer and frost barrier fill in addition to the fill currently in place, as a barrier controlling radon flux is anticipated to meet the regulatory requirements.
Material Taili>>gs Rod. Fall (Comp )
Clay (Sire # I )
Clay (Sire #4)
Clay (lff-1)
Material Twlmgs Rnd. Fill @ 80"/o Std Rod. Fill @ 85% Std Rnd. Fill @IJOIYo StJ Rod. Fill (ti! 95~i. Std Clay@ 95 ro StJ Spccifi(
Grnity*
(;.
2 M5 2 85 2 o7 2 67 2 69 2 69 2 75 2 75 2 19 Spedfic1* 1 Gravity G,
2 kS 2 ti7 2 h7 2 h7 2 r,7 2 72 Mn. Dcy*
\\lnit Wt.
Y-,....
(pd) 104 O 1()4_()
120 2 120 2 121 1 121.l IOX 7 IOX 7 Ill S Mlll. Dcy*161 Unit Wt y.,....
(pd)
NIA 120 2 I 2ll 2 120 2 120 2 I 110 0 t I ) 11= 1-( f\\1,Jl i/1\\, I l21 S=\\\\*t,.. 1\\h)/p,,/tli,*11~-1'J" 1 Mu. Dry Density p., __
j (g/cm)
I 67 I 67 I 93 I 93 I 94 1.94 I 74 1.74 1.82 Mlll. Dry Density p.,_.
(g/c:mj)
NIA I 43 I 93 I 9 3 1 *n I r-,O Table I Laboratory and Model Input Data LABORATORY DATA
'JS*/. Mn.
Poru~ity111 Dr)*
Radium Emanaliun Dr)* Dt*n!>ity Density Acti\\*ity Cocftkicnt
,.,..,.~~-,......,.
II (gfrm 1
)
(g/cmJ)
(pCi/g)
I SX II 4'11 I 45 9X I o 0 19 I 58 (j 4*J'i I 44 981 0 o I 'J I !U o _,01 I.XS I 9 0 I 'J un o 111 UM I. 9 0.19 I X:'i O 112 l 85 2.2 tl.20 1!!5 011h I 84 22 0 20 l.115 o 400 1.65 20 o 11 I r,5 0 4011 I hS 2 ()
o II I Tl.
0.2kO 1.72 I 5 O 22 SELECTED MODlt:L INPUT DATA Specified Pon1!iily 111 Dryt41 Radium"1 Emunulion1* 1 Dry Ocm;it~*
Dt:n1ity Activity Coctlidcnt r.,._
n p...,.
(g/cmJ)
(g/cmJ)
(pCi/g)
NIA o 5k, I I <J
'IX I II o 1 *1 I :'i4 114D I 54 I ')
0 I 'J I t.4 o 187 I 1>4 I 'J
() I 'J I 71 o 1:, I 17' I 9 o I 'J I x, 11, I 5 I !O I 'I o I 'J I S2 II 4*111 I 52 I 'I O IX
( lJ l>'---1107c>..pi-4(S-S1/-ts'111ic1 NRC wm.:lu1Jo11 (41 lai!mgs hascJ un '.74 2 pd RnJ Frll rung.:s front kO tu 'JS",., Std 1'1udor
(. 'lay hascJ un 'J'i'!l., StJ l'n11:to1 Water Diffu~ion 171 Content Cocftidcnt D
c*1. by wt.)
Crm2/!iocc)
IU 2 OOL-02 19 I X 4111:-tn 65 I tiOF-02 12.S 4 501:-04 8.1 I.60!:-02 12.6 I 4111:-0.l l S 4 I I Ol:-112
- 19. l 4.2ot-:-04 14.S 9 lllE-11, W.atcr1~1 Di1lu!1oi11111J1 Cu11tcnl Cocl'lidcnl
\\\\'
D
("/.. hy* \\\\'I.)
(rm2/scl) t, II
'i o7F-ll2
'J X 2 12Hl2
'J X I h2L-02 9X I I SF-02
'J.k 7 OSl:-01 14 I I JOF-02
( 5) T1ul111gs hascJ 1111 W"'h",.. per NRC Others huscJ 1111..:,1p1lh11v 111mslu1 c data
\\h) Values for da, arc,111 avc,agc oftest results RnJ Fill w:c'J X% anJ Clay w= 14 l'ro (average oll\\\\o tc:;ts)
(7) lmhv1Juul lah h:sl 1csuhs sum_thl xis S.1tun1tion111 Diflu,1011' 1'
( 'odlil ll'III s
I>
( l'DI l '"-'l I ll ll)(I 2 071 112 Ii 5 Sc.
I Ol,I II~
(I J'J2 I h,1, -02 O 740 I 11111 -11 I II 480 I 121 -11.'
o n4 2 I ~I.111 0 (,,5
'i 4XI 11, 117*11, I \\,II 11 I 11 X'ltl 2 X41 1;.j Saturalionili s
II 122 O "1~7 II 41 'i tl4X4 O 5 711 11 4XX
Figure 1 Cover Cross Sections for Radon Flux Models Case I Radon Flux 18.2 pCi/m2/s 14'(427cm}
95% Compaction Frost Barner Fill 1 O' (30 5 cm)
Clay Layer 1 o* (30 5 cm) 95% Compaction 1 O' (30 5 cm) 90% Compaction Platform Fill 1 o* (30 5 cm) 80% Compaction 16.4' (500 0 cm)
Tailings Case II Radon Flux 19.8 pCi/m2/s 1 4' (42 7 cm) 95% Compaction Frost Barner Fill 1.0' (30 5 cm)
Clay Layer 0.5' (15 2 cm) pa 1 o* (30 5 cm) 90% Compaction Platform Fill 1 5' (45 7 cm) 85% Compaction 16 4' (500 0 cm)
Tailings Note Percent compaction 1s based upon the maximum dry density by standard Proctor.
G \\1800t\\1826b\\llux ftgunuls 4/15199
~****! RADON !*****-----
Version 1.2 - Feb. 2, 1989 - G.F. Birchard tel.# (301)492-7000 U.S. Nuclear Regulatory Commission Office of Research RADON FLUX, CONCENTRATION AND TAILINGS COVER THICKNESS ARE CALCULATED FOR MULTIPLE LAYERS WHITE MESA CA-Sf= :X:::
CONSTANTS RADON DECAY CONSTANT RADON WATER/AIR PARTITION COEFFICIENT SPECIFIC GRAVITY OF COVER & TAILINGS GENERAL INPUT PARAMETERS LAYERS OF COVER AND TAILINGS DESIRED RADON FLUX LIMIT LAYER THICKNESS NOT OPTIMIZED DEFAULT SURFACE RADON CONCENTRATION SURFACE FLUX PRECISION LAYER 1 THICKNESS POROSITY LAYER INPUT PARAMETERS MEASURED MASS DENSITY MEASURED RADIUM ACTIVITY
.0000021
.26 2.65 6
20 0
0 500
.583 1.19 981 pCi m--2 pCi 1--1 pCi m--2 cm g cm--3 pCi/g--1 s --1 s --1 MEASURED EMANATION COEFFICIENT CALCULATED SOURCE TERM CONCENTRATION WEIGHT I MOISTURE
.19 7.990D-04 6
pCi cm--3 s--1 MOISTURE SATURATION FRACTION MEASURED DIFFUSION COEFFICIENT LAYER 2 THICKNESS POROSITY MEASURED MASS DENSITY MEASURED RADIUM ~CTIVITY MEASURED EMANATION COEFFICIENT CALCULATED SOURCE TERM CONCENTRATION WEIGHT I MOISTURE MOISTURE SATURATION FRACTION MEASURED DIFFUSION COEFFICIENT
.122
.0507 30.5
.423 1.54 1.9
.19 2.760D-06 9.8
.357
.0212 cm g cm--3 pCi/g--1
J,.A"fER 3 THICKNESS 30.5 cm POROSITY
.351 MEASURED MASS DENSITY
- 1. 73 g cm--3 MEASURED RADIUM ACTIVITY 1.9 pCi/g--1 MEASURED EMANATION COEFFICIENT
.19 CALCULATED SOURCE TERM CONCENTRATION 3.737D-06 pCi cm--3 s--1 WEIGHT% MOISTURE 9.8 MOISTURE SATURATION FRACTION
.483 MEASURED DIFFUSION COEFFICIENT
.0115 cm-2 s--1 LAYER 4 THICKNESS 3v.5 cm POROSITY
.315 MEASURED MASS DENSITY 1.83 g cm--3 MEASURED RADIUM ACTIVITY 1.9 pCi/g--1 MEASURED EMANATION COEFFICIENT
.19 CALCULATED SOURCE TERM CONCENTRATION 4.404D-06 pCi cm--3 s~-1 WEIGHT I MOISTURE 9.8 MOISTURE SATURATION FRACTION
.569 MEASURED DIFFUSION COEFFICIENT
.0071 cm-2 s--1 LAYER 5 THICKNESS 30
- r cm POROSITY
.44 MEASURED MASS DENSITY
- 1. 52 g cm--3 MEASURED RADIUM ACTIVITY 1.9 pCi/g--1 MEASURED EMANATION COEFFICIENT
.18 CALCULATED SOURCE TERM CONCENTRATION 2.481D-06 pCi cm--3 s--1 WEIGHT% MOISTURE 14.1 MOISTURE SATURATION FRACTION
.487 MEASURED DIFFUSION COEFFICIENT
.013 cm-2 s--1 LAYER 6 THICKNESS 42.7 cm POROSITY
.315 MEASURED MASS DENSITY 1.83 g cm--3 MEASURED RADIUM ACTIVITY 1.9 pCi/g--1 MEASURED EMANATiON COEFFICIENT
.19 CALCULATED SOURCE TERM CONCENTRATION 4.404D-06 pCi cm--3 s--1 WEIGHT I MOISTURE 9.8 MOISTURE SATURATION FRACTION
.569 MEASURED DIFFUSION COEFFICIENT
.0071 cm-2 s--1
DATA SENT TO THE FILE 'RNDATA' ON DRIVE A:
N FOl CNl ICOST CRITJ ACC 6
-1.0000+00 O.OOOD+OO 0
2.0000+01 0.0000+00 LAYER DX D
p Q
XMS RHO 1
5.0000+02 5.0700-02 5.8300-01 7.9900-04 1.2250-01 1.190 2
3.0500+01 2.1200-02 4.2300-01 2.7600-06 3.5680-01 1.540 3
3.0500+01 1.1500-02 3.5100-01 3.7370-06 4.8300-01 1.730 4
3.0500+01 7.1000-03 3.lSOD-01 4.4040-06 5.6930-01 1.830 5
3.0500+01 1.3000-02 4.4000-01 2.4810-06 4.8710-01 1.520 6
4.2700+01 7.1000-03 3.1500-01 4.4040-06 5.693D-01 1.830 BARE SOURCE FLUX FROM LAYER 1:
6.9380+02 pCi m--2 s--1 RESULTS OF THE RADON DIFFUSION CALCULATIONS LAYER THICKNESS EXIT FLUX EXIT CONC.
(cm)
(pCi m--2 s--1) (pCi 1--1) 1 5.0000+02 1.4170+02 2.9110+05 2
3.050D+Ol 8.3830+01 1.976D+05 3
3.0500+01 5.1580+01 l.2200+05 4
3.0SOD+Ol 3.6080+01 5.1460+04 5
3.050D+Ol 2.274D+Ol 4.139D+04 6
4.270D+Ol l.824D+Ol 0.0000+00
t****! RADON!*****-----
Version 1.2 - Feb. 2, 1989 - G.F. Birchard tel.# (301)492-7000 U.S. Nuclear Regulatory Commission Office of Research RADON FLUX, CONCENTRATION AND TAILINGS COVER THICKNESS ARE CALCULATED FOR MULTIPLE LAYERS WHITE MESA CA'Sc ::re.
CONSTANTS RADON DECAY CONSTANT RADON WATER/AIR PARTITION COEFFICIENT SPECIFIC GRAVITY OF COVER & TAILINGS GENERAL INPUT PARAMETERS LAYERS OF COVER AND TAILINGS DESIRED RADON FLUX LIMIT LAYER THICKNESS NOT OPTIMIZED DEFAULT SURFACE RADON CONCENTRATION SURFACE FLUX PRECISION LAYER 1 THICKNESS POROSITY LAYER INPUT PARAMETERS MEASURED MASS DENSITY MEASURED RADIUM ACTIVITY MEASURED EMANATION COEFFICIENT CALCULATED SOURCE TERM CONCENTRATION WEIGHT I MOISTURE MOISTURE SATURATION FRACTION MEASURED DIFFUSION COEFFICIENT LAYER 2 THICKNESS POROSITY MEASURED MASS DENSITY MEASURED RADIUM ACTIVITY MEASURED EMANATION COEFFICIENT CALCULATED SOURCE TERM CONCENTRATION WEIGHT I MOISTURE MOISTURE SATURATION FRACTION MEASURED DIFFUSION COEFFICIENT
.0000021
.26 2.65 6
20 0
0 500
.583 1.19 981
.19 7.990D-04 6
.122
.0507 45.7
.387 1.64 1.9
.19 3.2130-06 9.8
.415
.0162 pCi m --2 pCi 1--1 pCi m --2 cm cm g cm--3 pCi/g--1 s --1 s --1
LAYER 3 THICKNESS 30.5 cm POROSITY
.351 MEASURED MASS DENSITY 1.73 g cm--3 MEASURED RADIUM ACTIVITY 1.9 pCi/g--1 MEASURED EMANATION COEFFICIENT
.19 CALCULATED SOURCE TERM CONCENTRATION 3.737D-06 pCi cm--3 s--1 WEIGHT% MOISTURE 9.8 MOISTURE SATURATION FRACTION
.483 MEASURED DIFFUSION COEFFICIENT
.0115 cm-2 s--1 LAYER 4 THICKNESS 15.2 cm POROSITY
.315 MEASURED MASS DENSITY 1.83 g cm--3 MEASURED RADIUM ACTIVITY 1.9 pCi/g--1 MEASURED EMANATION COEFFICIENT
.19 CALCULATED SOURCE TERM CONCENTRATION 4.4040-06 pCi cm--3 s--1 WEIGHT% MOISTURE 9.8 MOISTURE SATURATION FRACTION
.569 MEASURED DIFFUSION COEFFICIENT
.0071 cm-2 s--1 LAYER 5 THICKNESS 30.5 cm POROSITY
.44 MEASURED MASS DENSITY 1.52 g cm--3 MEASURED RADIUM ACTIVITY 1.9 pCi/g--1 MEASURED EMANATION COEFFICIENT
.18 CALCULATED SOURCE TERM CONCENTRATION 2.481D-06 pCi cm--3 s--1 WEIGHT% MOISTURE 14.1 MOISTURE SATURATION FRACTION
.487 MEASURED DIFFUSION COEFFICIENT
.013 cm-2 s--1 LAYER 6 THICKNESS 42.7 cm POROSITY
.315 MEASURED MASS DENSITY 1.83 g cm--3 MEASURED RADIUM ACTIVITY 1.9 pCi/g--1 MEASURED EMANAT!bN COEFFICIENT
.19 CALCULATED SOURCE TERM CONCENTRATION 4.404D-06 pCi cm--3 s--1 WEIGHT I MOISTURE 9.8 MOISTURE SATURATION FRACTION
.569 MEASURED DIFFUSION COEFFICIENT
.0071 cm-2 s--1
DATA SENT TO THE FILE -RNDATA' ON DRIVE A:
N FOl CNl ICOST CRITJ ACC 6
-1.0000+00 0.0000+00 0
2.0000+01 0.0000+00 LAYER DX 0
p Q
XMS RHO 1
5.0000+02 5.0700-02 5.8300-01 7.9900-04 1.2250-01 1.190 2
4.S70D+Ol 1.6200-02 3.8700-01 3.2130-06 4.153D-Ol 1.640 3
3.0500+01 1.1500-02 3.5100-01 3.7370-06 4.8300-01 1.730 4
1.5200+01 7.1000-03 3.1500-01 4.4040-06 5.6930-01 1.830 5
3.0500:01 1.3000-02 4.4000-01 2.4810-06 4.8710-01 1.520 6
4.2700+01 7.1000-03 3.1500-01 4.4040-06 5.5930-01 1.830 BARI SOURCE FLUX FROM LAYER 1 :
6.9380+02 pCi m--2 s--1 RESULTS OF THE RADON DIFFUSION CALCULATIONS LAYER THICKNESS EXIT FLUX EXIT CONC.
(cm)
{pCi m--2 s--1) (pCi 1--1) 1 5.0000+02 1.3820+02 2.930D+05 2
4.570D+Ol 7.1310+01 1.4850+05 3
3.0500+01 4.6020+01 9.4000+04 4
1.5200+01 3.9210+01 5.5860+04 5
3.0500+01 2.469D+Ol 4.4910+04 6
4.270D+Ol 1.977D+Ol 0.0000+00