ML20015A372

Attachment - NRC-2020-000076 - Appeal Response to NRC-2019-000132. (Part 22 of 29)

ML20015A372
Person / Time
Issue date:	01/08/2020
From:	NRC/OCIO
To:
Shared Package
ML20015A350	List: ML20015A351 ML20015A353 ML20015A354 ML20015A355 ML20015A356 ML20015A357 ML20015A358 ML20015A359 ML20015A360 ML20015A361 ML20015A362 ML20015A363 ML20015A364 ML20015A365 ML20015A366 ML20015A367 ML20015A368 ML20015A369 ML20015A370 ML20015A371 ML20015A372 ML20015A373 ML20015A374 ML20015A375 ML20015A376 ML20015A377 ML20015A378 ML20015A379 ML20015A380
References
FOIA, NRC-2019-000132, NRC-2020-000076
Download: ML20015A372 (93)

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Pagr \\ Revision 2 O International l :ranium ( l ISA) (\\1rp White Mesa Mill Rt:damati1m Plan TABLE Of' CONTENTS (continued)

2 1. I Mill Building and Fquiprnent 1

1. L: Mill Sitl:

IH*Sl<,N ('RlflRIA '. 1 l Rcgulatnn l 'ntcria ~ l.. 1 Radon Flu.,,\\ ttcnuation. ' l..~. I Pred1ctin~ Analysis ' 1.. ~.2 Empirical Data '\\ \\., Infiltration Analysis \\ \\4 hec1c/Thaw Fvaluation \\ 1, Soil Cover Erosion Protection l lb Slope Stahility Analysis ~ 61 Statil: Analysis

1. 1.6.:?. Pseudostatic Analysis ( Seismicity) 1 t I Soil Cover.. Animal Intrusion

. Ui Cover ~1aterial/Covt~r Material Volumes Page Nn.

.1-l 0 {. I '\\ 1-l 1 J-14 1-14 1-16 .Ll7 1 -19 ~-19 1-21 3-22 1.n J

2. 3 Y2J

TABLE l.l-1 TABLE l.3-1 TABLE 1.4-1 TABLE 1.5-1 TABLE l.5.3.1-1 TABLE 1.5.3.1-2 TABLE 1.5.J.2-l TABLE 1.5.3.2-2 TABLE L5. 5-1 Page vi Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan LIST OF TABLES Page No. Temperature Means and Extremes at IJlanding, Utah............. 1-8 (Table 2.1. I Dames & Moore -Final ES) Precipitation Means and Extremes at Blanding, Utah.............. 1-9 (Table 2.1-2 Dames & Moore -Final ES) Distribution of Recorded Sites According...................... 1-12 to Temporal Position (Table 2.3-2 Dames & Moore -Final ES) Drainage Areas of Project Vicinity and Region.................. l-18 (Table 2.6-3 Dames & Moore -Final ES) Wells Located Within a 5-Mile Radius of the White Mesa Uranium Mill............................... 1-33 (Table l. l Titan) Properties of the Dakota/Burro Canyon Formations, White Mesa Uranium Mill............................... l-39 (Table 2.1 Titan) Summary of Hydraulic Properties, White Mesa Uranium Mill......................................... 1-40 (Table 2.2 Titan) Summary of Borehole Tests, 1994 Drilling Program, White Mesa Project, San Juan County, Utah................. Results of Laboratory Tests................................. 1-53 Monitoring Well and Ground Water Elevation Data, White Mesa Uranium Mill.............................. 1-59 (Table 2.3 Titan) H 1USEll!IIWMRCPLAN\\'f ABI.E l.ST\\MAy 1999

TABLE l.6-l f ABLE l.6-2 TABLE 1.6-3 TABLE 1.7-l TABLE l.7-2 TABLE l.7-3 TABLE l.7-4 TABLE 5.3.2.1-1 TABLE 8-I Page vii Revision 2.0 International Uranium ( USA) Corp. White Mesa Mill Reclamation Plan LIST OF TABLES (continued) Page No. Generalized Stratigraphic Section of Subsurface Rocks Based on Oil-Well Logs............................... 1-69 (Table 2.6-1 UMETCv) Generalized Stratigraphic Section of Exposed Rocks in the Project Vicinity................................ I-70 (Table 2.6-2 UMETCO) Modified Mercalli Scale, 1956 Version....................... l -89 (Table 2.6-3 UMETCO) Community Types and Expanse Within the Project Site Boundary................................. 1-104 (Table 2. 7-1 UMETCO) Ground Cover for Each Community Within the Project Site Boundary................................ l-104 Birds Observed in the Vicinity of the White Mesa Project............................................ 1-107 (Table 2. 7-3 UMETCO) Threatened and Endangered Aquatic Species Occurring in Utah.................................. 1-1 l 1 (Table 2.7*-4 UMETCO) Placement and Compaction Criteria Reclamation Cover Materials.................................. Page A-24 Required Reports.................................... Page B-14 H \\lJSEJlS\\WMIKPLAN\\TABLE LST'May 1999

FIGURE 1-1 FIGURE 1-2 FIGURE 1.4-1 FIGURE 1.4-2 FIGURE l.4-3 FIGURE 1.5. l LIST OF FIGURES Page viii Revisi0n 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan Page No. White-Mesa Mill Regional Location Map...................... 1-3 White Mesa Mill Location Map............................... 1-4 Drainage Map of the Vicinity of the White Mesa Project.......... 1-1 7 (Adapted from Dames & Moore (1978b), Plate 2.6-5) Streamtlow Summary in the Blanding, Utah Vicinity............. 1-21 (Adapted from Dames & Moore (1978b), Plate 2.6-6) Preoperational Water Quality Sampling Stations in the White Mesa Project Vicinity..................... 1-21 (Adapted from Dames & Moore (1978b), Plate 2.6-10) Colorado Plateau Geologic Map (Titan Figure 1.1) ............................. 1-27 FIGURE 1.5-2 Generalized Stratigraphy of White Mesa....................... 1-29 (Titan Figure 1.2) FIGURE 1.5-3 Ground Water Appropriation Applications Within a 5-Mile Radius...................................... 1-32 (Titan Figure 1.3) FIGURE l.5.3.1-l Site Plan Map (Showing Cross Sections)...................... 1-45 (Titan Figure 2.1) FIGURE l.5.3.1-2 Cross Section A-A' West to East Through White Mesa Westwater Creek to Corral Canyon..................... 1-48 (Titan Figure 2.2) FIGURE l.5.3J-3 Cross Section Il-8' North to South Through White Mesa North of Facility to Cottonwood Wash.................. 1-49 H il;SERS\\WMRCPLAN\\FIGL'RE LSl\\May 1m

FIGURE J.5.5-1 FIGURE 1.5.5-2 FIGURE 1.5.5-3 FIGURE 1.6-1 FIGURE 1.6-2 FIGURE I.6-3 FIGURE 1.6-4 FIGURE 1.6-5 FIGURE l.6-6 Page ix Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan LIST OF f'IGURES (continued) Page No. Perched Ground Water Levels.............................. 1-56 (Titan Figure 2.4) Saturated Thickness of Perched Water....................... 1-5 7 (Titan Figure 2.5) Topography of Brushy Basin................................ 1-58 (Titan Figure 2.6) Tectonic Index Map...................................... 1-68 White Mesa Millsite-Geology of Surrounding Area.............. 1-80 Seisrnicity 320km Around Blanding, Utah Seisrnicity 200km. Around Blanding, Utah ,.92 Seismicity of the Western United Stat~s. 1950 to 1979............ 1-93 Colorado Lineament..................................... 1-97 FIGURE 1. 7-1 Community Types on the White Mesa Project Site.............. 1-103 FIGURE 3. l-1 White Mesa Mill Regir,aal Map Showing Land Position.......... 3-3 FIGURE 3.2-1 White Mesa Mill C*.1eral Layout Showing Access and Restricted Area. Boundary............................. 3-5 FIGURE 3.2.3-1 Site Map Showing Locations of Buildings and Tanks............. 3-12 FIGURE A-2.2.4-1 Sedimentation Basin Detail............................... A-4 H \\USERS1WMRCPLAN\\flGL1lE LSTIMay 1999

FIGURE A-3.2-1 FIGURE A-3.3-l FIGURE A-3.3-2 FIGURE A-5.1-l FIGURE A-5.1-2 FIGURE A-5.1-3 FIGURE c3-I Page x Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan LIST OF FIGURES (continued) Page No. Mill Site and Ore Pad Final Grading Plan...................... A-8 TypicJ.J Scanning Path Scoping Survey...................... A-14 Standard Sampling Pattern for Systematic Grid Survey of Soil.... A-15 Reclamation Lover Grading Plan for Cells 2 and 3.............. A-19 Reclamation Cover and Cross Sections....................... A-20 Reclamation Cover Cross Section and Details................ A-21 Typical Flow Chart for Construction Project.................... 8-22 H *USERSIWMRCPLA.N\\flGURE 1.Sl\\M*y 1'19'1

Attachment A B C D E F G H Appendix A B C D E Page xi Revision 2.0 International Uranium Corp. White Mesa Reclamation Plan LIST OF ATTACHMENTS Plans and Specifications for Reclamation of White Mesa Mill Facility, Blanding, Utah. Quality Plan for Construction Activities, White Mesa Project, Blanding, Utah. Cost Estimates for Reclamation of White Mesa Facility in Blanding, Utah. Reclamation Material Characteristics Evaluation of Potential Settlement Due to Earthquake-Induced Liquefaction and Probabilistic Seismic Risk Assessment Radon Emanation Calculations (Revised) Channe and Toe Apron Design Calculations of White Mesa Facilities in Blanding, Utah. Rock Test Results - Blanding Area Gravel Pits LIST OF APPENDICES (Previously Submitted with Revision 1.0, February 28, 1997) Semi-Annual Effluent Report. White Mesa Mill. SUA-1358 Docket No. 40-8681 (July - December 1995) and Semi-Annual Effluent Report, White Mesa Mill SUA-135~ Docket No. 40-8687 January - June 1996. Energy Fuels Nuclear, Inc. Hydrogeologic Evaluation of White Mesa Uranium Mill, (July 1994 ). Titan Environmental Corporation. Points of Compliance. White Mesa Uranium Mill. September 1994. Titan Environmental Corporation. Tailings Cover Desian, White Mesa Mill, October 1996. Titan Environ.mental Corporation. Neshaps Radon Flux Measurement Proaram. White Mesa Mill. October 1995. Tellco Environmental Corporation.

REFERENCES Page xii Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan Abt, S. R., 1987. Engineering and Design of Wa'ite Disposal Systems, Mini-course No. 7: Riprap Design for Reclamation. Agenbroad, L. D. et. al.. 198 L 1980 Excavations in White Mesa, San Juan County, Utah. (Cited in 1.3.2) Aki. K., 1979. Characterization of Barriers on an Earthquake Fault, Journal of Gr.ophysical Research, v. 84, pp. 6140-6148. Algermissen, S. T. and Perkins. D. M.. 1976. A Probabilistic Estimate of Maximum Acceleration on Rock in the Contiguous United States, U. S. Geological Survey Open-File Report, No. 76-4 i 6. Anderson, L. W. and Miller, D. G., 1979. Quartemary Fault Map of Utah, FURGO, Inc. Arabasz, W. J., Smith, R. 8., and Richins, W. D., eds., 1979. Earthquake Studies in Utah 1850 to I 978, Special Publication of the University of Utah Seismograph Stations, Department of Geology and Geophysics. Bonilla. M. G., Mark, R. K., and Lienkaemper, J. J., 1984. Statistical Relations Among Earthquake Magnitude, Surface Rupture Length, and Surface Fault Displacement, Bulletin of the Seismological Society of America, v. 74, No. 6, pp. 2379-2411. Brill, K. G. and Nuttli, 0. W., 1983. Seismicity of the Colorado Linea1t1ent, Geology, v. 11, pp. 20-

24.

Case, J. E. and Joesting, H. R., 1972. Regional Geophysical Investigations in the Central Plateau, U. S. Geological Survey Professional Paper 736. Casjens, L. A. et. al., 1980. ArcheoJogical Excavations on White Mesa, San Juan County, Utah, 1979; Volumes I through IV; June, 1980. (Cited in 1.3.2) Cater, F. W., 1970. Geology of the Salt Anticline Region in Southwestern Colorado, U. S. Geological Survey, Professional Paper 637. H \\USEAS\\WMRCPLNIWHITEMMSA.REF\\May 1999

Page.\\iii Rr vision 2.0 International Uranium f{ rs/\\~ Ci)rp White Mesa Mill Reclamatwn Plan Chen and Associates. Inc., 1978. Soil Property Study, Earth Lined Tailr, ~s Retentton Cdls. White Mesa lJ ranium Project, Blandirg. Utah. Chen and Associates. Inc.. l 979. Soil Property Study, Proposed Tailings Retention Cells. White Mesa Uranium Project, Blanding. Utah. Cook, K. L. and Smith. R. B.. 1967. Seismicity in Utah, 1850 Through June 1965. Bull. Sei-,m. S11c. Am., v. 57. pp. 689-718. Coulter, H. W., Waldron, H. H.. and Devine, J. F., 1973. Seismic and Crenlogic Siting Considerations for Nuclear Facilities, Proceedings. Fifth We.rid Conference on Earthquake Engineering, Rome, Paper 302 Craig, L. C., et. al., 1955. Stratigraphy of the Morrison and Related Fomiations. Colorado Plateau Region, a Preliminary Report, U.S. Geological Survey Bulletin 1009-E, pp. 125-168. Dames and Moore, 1978, "Environmental Report, White Mesa Uranium Project, San Juan County. Utah." Prepared for Energy Fuels Nuclear, [nc., January. Dames and Moore, 1978a. Site Selection and Design Study - Tailing Retention and Mill Facilities. White Mesa Uranium Project, January 17. 1978. Dames and Moore, 1978b. Environmental Report, Whtte Mesa Uranium Project, San Juan County, Utah, January 20, 1978, revised May 15, 1978. (Cited in Section 1.0) D'Appolonia Consulting Engineers, Inc., 1979. Engineer's Report -*.:.ilings Management System, \\\\11ite Mesa Uranium Project, Blanding, Utah. D'Appolonia Consulting Engineers, Inc, 198 l, Letter Report, "Assessment of the Water Supply System, White Mesa Project, Blanding. Utah." Prepared for Energy Fuels Nuclear, Inc., February. D'Appolonia Consulting Engineers, Inc., 1981 a. Engineer's Report, Second Phase Design - Cell 3 Tailings Management System, White Mesa Uranium Project, Blanding, Utah. D'Appolonia Consulting Engineers, Inc., 1981 b. Letter Report, Leak Detection System Evaluatio~. White Mesa Uranium Project, Blanding, Utah. H \\USERS\\WMRCPLN\\WHITF.MMSA REf\\May 1999

Page xiv Revision 2 0 International Uranium (USA) Corp. White ~1esa Mill Reclamation Plan D'Appolonia Consulting Engineers, Inc.. 1982. Construction Report, Initial Phase - Tailings Management System, White Mesa Uranium Project. Blanding, Utah." Prepared for Energy Fuels Nuclear, Inc., February. D'Appolonia Consulting Engineers, Inc.. 1982a. Construction Report, Initial Phase - Tailings Management System, White Mesa Uranium Project, Blanding, Utah. [)'Appolonia Consulting Engineers, Inc., 1982b. Monitoring Plan - Initial Phase - Tailings Management System - White Mesa Uranium Project. Blanding, Utah. D' Appolonia Consulting Engineers, (nc., 1982c. Letter Report -Groundwater Monitoring Program - White Mesa Uranium Project, Blanding, Utah. D' Appolonia Consulting, Engineers, lnc., 1982d. Letter Report** Additional Analysis Tailings Cover Design Revisions - White Mesa Uranium Project, Blanding, Utah. D'Appolonia Consulting Engineers. Inc., 1984, "Engineer's Report, Geotechnical Site Evaluation, Farley Project, Garfield County, Utah." Prepared for Atlas Minerals. Moab, Utah, June. Energy Fuels Nuclear, Inc., 1983. Construction Report - Second Phase Tailings Management System, \\Vhite Mesa Uranium Project. Energy Fuels Nuclear, Inc., 1996. Semi-annual Effluent Report, July - December, 1995, Report Submitted by William Deal on February 26, 1996, to U.S. Nuclear Regulatory Commission. Eardly, A. J., I Y58. Physiography of Southeastern Utah in lntermountain Association Petroleum Geologists Guidebook, 9th Annual Field Conference, Geology of the Paradox Basin, pp. I 0-

15.

Feltis, R. 0., 1966. Water from Bedrock in the Colorado Plateau of Utah, Utah State Engineer Technical Publication No. 15. Grose, L. T.. 1972. Tectonics, in Geologic Atlas of the Rocky Mountain Region Rocky Mountain Association Geologists, Denver, Colorado. pp. 35-44. H \\USBJlSIWMRCPLN\\WHJ'ft!MM!A llEF\\May 1999

Page xv Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan Hadsell, F. A., 1968. History of Earthquakes in Colorado, in Hollister, J. S. and Weimer, R. J., eds., Geophysical and Geological Studies of the Relationships Between the Denver Earthquakes and the Rocky Mountain Arsenal Well, Colorado School Mines Quarterly, v 63, No. l, pp. 57-72. Haynes, D.D., Vogel, JD., and Wyant, D.G., 1972, "Geology, Structure and Uramum Deposits of the Cortez Quadrangle, Colorado and Utah." U.S. Geological Survey, Miscellaneous Investigation Sen~s, Map. 1-629, May. Hermann, R. B., Dewey, J. W., and Park, S. F.* 1980. The Dulce, New Mexico. Earthquake of January 23. 1966, Seismological Society of America Bulletin, v. 70, No. 6, pp. 2 l 7 l-2183. Hite, R. J., 1975. An Unusual Northeast-trending Fracture Zone and its Relation to Basement Wrench Faulting in Northern Paradox Basin, Utah and Colorado, Four Corners Geological Society 8th Field Conference Guidebook, Durango, Colorado, pp. 217-223. Huff, L. D., and Lesure, F. G., 1965. Geology and Uranium Deposits of Montezuma Canyon Area, San Juan County, Utah, U.S. Geological Survey Bulletin 1190, 102 p. Hunt, C. B., 1956. Cenozoic Geology of the Colorado Plateau: U.S. G. S. Professional Paper, 279. Hydro-Engineering, 1991, "Ground Water Hydrology at the White Mesa Tailings Facility." Prepared for Umetco Minerals Corporation, Blanding, Utah, July. Johnson, H. S, Jr., and Thordarson, W.. 1966. Uranium Deposits of the Moab, Monticello, White Canyon, and Monument Valley Districts, Utah and Arizona, U. S. Geological Survey Bulletin 1222-H, 53 p. Keend, W. E., 196'-l Quaternary Geology of the Grand and Battlement Mesa Area, Colorado: U.S.G.S. Professional Paper, 617. Kelley, V. C., 1955. Regional Tectonics of the Colorado Plateau and Relationship to the Origin and Distribution of Uranium, New Mexico University Publication Geology No. 5, 120 p. Kelley, V.C., 1958, "Tectonics of the Region of the Paradox Basin." In lntermountain Association Petroleum Geologists Guidebook, 9th Annual Field Conference, Geology of the Paradox Basin, p. 31-38. H \\USEltS\\WMRCPLN\\WHITEMMSA I\\EFMay 1999

Page xvi Revision 2.0 fnternational Uraniwn (USA) Corporation \\Vhite Mesa Mill Reclamation Plan Kirkham. R. M. and Rogers, W. P.. 1981. Earthquake Potential in Colorado, A Preliminary Evaluation, Colorado Geological Survey, Bulletin 43. Krinitzsky, E. L. and Chang, F. K., l 97 5. State-of-the-Art for Assessing Earthquake Hazards in the United States, Earthquake Intensity and the Selection of Gwund Motions for Seismic Design, Miscellaneous Paper S-73-1, Report 4, September 1975, U. S. Army Engineer Waterways Experiment Station, CE. Vicksburg, Mississippi. Larson, E. E., et. al., 1975. Lai... : Cenozoii..: Basic Volcanism in Northwestern Colorado and its Implications Concerning Tectonics and the Colorado River System in Cenozoic History of Southern Rocky Mountains: Geological Society of America, Memoir 144. Lindsay, L. M. W., 1978. Archeological Test Excavations on White Mesa, San Juan County, Southeastern Utah. (Cited in 1.3.2) National Oceanic and Atmospheric Administration (NOAA), 1977. Probable Maximum Precipitation Estimates, Colorado River and Great Basin Drainages. Hydrometerological Report (HMR) No. 49. National Oceanic and Atmospheric Administration (NOAA), 1988. Computer Printout of Earthquake File Record for 320 km Radius of Blanding, Utah. U. S. Department of Commerce, National Geophysical Data Center, Boulder, Colorado. Nielson, A. S., 1979. Additional Archeological Test Excavations and Inventory on White Mesa, San Juan County, Southeastern Utah. (Cited in 1.3.2) NUREG/CR-1081, March 1980. Characteriz.ation of U raniurn Tailings Cover Materials for Radon Flux Reduction. NUREG/CR-2642, June 1982. Long-term Survivability of Riprap for Armoring Uranium Mill Tailings and Covers: A Literature Review. NlJREG/CR-2684, August 1982. Rock Riprap Design Methods and Their Applicability to Long-term Protection of Uranium Mill Tailings Impoundments. NUREG/CR~3027, March l 983~ Overland Erosion of Uranium Mill Tailings Impoundments Physical Processes and Computational Methods. H \\USERSIWMII.CPLN\\WHITEMMSA RE.F\\May 1999

Page xvii Revision 2.0 International Uram um ( USA) Corp. White Mesa Mill Reclamation Plan NUREG/CR-3061, November 1983. Survivability of Ancient Man-made Mounds: Implications for Uianium Mill Tailings lmpoundment. NlJREG/CR-3199, October 1983. Guidance for Disposal of Uranium Mill Tailings: Long-term Stabilization of Earthen Cover Materials. NUREG/CR-3397, October 1983. Design Considerations for Long-term Stabilization of Uranium Mill Tailings Impoundments. NUREG/CR-3533, February 1984. Radon Attenuation Handbook for Uraniwn Mill Tailings Cover Design. NUREG/CR-3674, March 1984. Designing Vegetation Covers for Long-term Stabilization of Uranium Mill Tailings. NUREG/CR-3747, May 1985. The Selection and Testing of Rock for Armoring Uranium Tailings Impoundments. NUREG/CR-3972, December 1984. Settlement of Uranium Mill Tailings Piles. NUREG/CR-4075, May 1985. Designing Protective Covers for Uranium Mill Tailings Piles: A Review. NUREG!CR-4087, February, 1985. Measurements of Uranium Mill Tailings Consolidation Characteristics. NUREG/CR-4323, January 1986. The Protection of Uranium Tailings Impoundments against Overland Erosion. NlJREG/CR-4403, November t 985. Summary of the Waste Management Programs at Uranium Recovery Facilities as They Relate to the 40 CFR Part 192 Standards. NUREG/CR-4480, September 1986. Erosion Protection of Uranium Tailings lmpoundment. NUREG/CR-4504, March 1986. Long-term Surveillance and Monitoring of Decommissioned Uranium Processing Sites and Tailings Piles. H \\USERSIWMJI.CPLN\\WHJTF.MMSA REF\\May t *J<)9

Page xviii Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan NUREG/CR-4520, April 1986. Predictive Geochemical Modeling of Contaminant Concentrations in Laboratory Columns and in Plumes Migrating from Uranium Mill Tailings Waste Impoundments. NUREG/CR-4620, June, 1986. Methodologies for Evaluating Long-Term Stahilization Designs of Uranium Mill Tailings Impoundments, J. D. Nelson, S. R Abt.. et. al. NUREG/CR-4651, May 1987. Development ofRiprap Design Criteria by Riprap Testing in Flumes: Phase L Nuttli, 0. W., 1979. State-of-the-Art for Assessing Earthquake Hazards in the United States, Part 16: The Relation of Sustained Maximum Ground Acceleration and Velocity to Earthquake Intensity and Magnitude, with Errata Sheet of January 11, 1982; U. S. Anny Engineers Waterways Experiment Station, Vicksburg, P. 0. No. DACW39-78-C-0072.67 p. with Two Appendices and 2 p. Errata. Roger and Associates Engineering Company, 1988. Radiological Properties Letters to C 0. Sealy from R. Y. Bowser dated March 4 and May 9, 1988. Schroeder, P. R., J. M. Morgan, T. M. Walski, and AC. Gibson, 1989, Technical Resource Document, The Hydrologic Evaluation of Landfill Performance (HELP) Model, Version IL" U.S. Environmental Protection Agency. Seed, H. B. And Idriss, I. M., 1982. GrounJ Motions and Soils Liquefaction During Earthquakes, Earthquake Engineering Research Institute, Berkeley, California. Shoemaker, E. M., I 954. Structural Features of Southeastern Utah and Adjacent Parts of Colorado. New Mexico, and Arizona. Utah Geoiogical Society Guidebook to the Geology of Utah, No. 9, pp. 48-69. Shoemaker, E.M., 1956, "Structural Features of the Colorado Plateau and Their Relation to Uranium Deposits." U.S. Geological Survey Professional Paper 300, p. 155-168. Simon, R. B., 1972. Seismicity, in Mallory, W. W., and Others, eds. Geologic Atlas of the Rocky Mountain Region, Rocky Mountain Association of Geologists, pp. 48-5 I. H.IUSllllS\\WMJI.CPlN\\WHITEMMSA llEF\\May 1'1'19

Page xix Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan Slemmons, D. B.. I Q77. State-of-the-Art for Assessing Earthquake Hazards in the United States, Part 6. Faults and Earthquake Magnitude, with an Appendix on Geomorphic Features of Active Fault Zones. U. S. Army Engineer Waterways Experiment Station, Vicksburg. Contract No. DACW39-76-C-0009, 129 p. plus 3 / p. Appendix. Smith, R. 8., 1978. Seismicity. Crustal Structure, and lntraplate rectonics of the Western Cordillera, in Cenozoic Tectonics and Regional Geophysics of the Western Cordillera. Smith, R. B. and Eaton. G. P., eds. Memoir 152. Geological Society of America, pp. 111.. 144. Smith. S., l 981. Long-Term Stability at Union Carbide's Tailings Piles in { Jravan, Colorado. Stephenson, D., 1979. RockfiH in Hydraulic Engineering, Developments in Oeotechnical Engineering, 27. Elsevier Scientific Publishing Company, pp. 50-60. See NUREG 4620. Stokes, W. L.. 1954. Stratigraphy of the Southeastern Utah Uranium Region, lJtah Geological Society Guidebook to the Geology of Utah, No. 9, pp. 16-47. Stokes. W. L, 1967. A Survey of Southeastern Utah Uranium Districts, Utah Geological Sodet) Guidebook to the Geology of Utah, No. 21, pp. l ** 11. Thompson, K. C., 1967. Structural Features of Southeastern Utah and Their Relations to Uranium Deposits, Utah Geological Society Guidebook to the Geology of Utah, No. 21. pp. 23-31 Titan Environmental Corporation, 1994a. Hydrogeologic Evaluation of White Mesa Uranium Mill. Titan Environmental Corporation, 1994b. Points of Compliance, White Mesa Uranium Mill. Trifunac, M. D. and Brady, A.G. On the Correlation of Seismic Intensity Scales with the Peaks of Recorded Strong Ground Motion, Seismological Society of America Bulletin, V 6\\ Feb. I 975, pp. J 39~ 162. Umetco, 1987. Umetco MineraJs Corporation SUA~l 358: Docket No. 40-8681, License Condition 48, White Mesa Mill. Utah, Letter From R. K. Jones to U. S. Nuclear Regulatory Commission dated November 30, 1987. H 1U5£AS\\WMRCPLN\\WH1TfiMMSA JU!.li\\May 19'19

Page xx Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan Umetco Minerals Corporation. 1992, "Ground Water Study, White Mesa Mill, Blanding, Utah, License SU A 1358. Docket No. 40-868 l. United States Geological Survey, 1970. U.S. Department of Energy. 1993, "Environmental Assessment of Remedial Action at the Slick Rock Uranium Mill Tailings Sites, Slick Rock, Colorado." UMTRA Project Offke. Albuquerque. New Mexico, February. {!. S. Nuclear Regulatory Commission. 1977. Regulatory Guide 3. I l. Design, Construction. and Inspection of Embankment Retention Systems for Uranium Mills, Revision 2. 1977. U. S. Nuclear Regulatory Commission, I 979. Final Environmental Statement - White Mesa Uranium Project, Nl!REG-0556. (Cited in Section 1.0) U. S. Nuclear Regulatory Commission, 1985. Standard Review Plan for UMTRA litk i ~till Tailings

• Remedial Action Plans. Division of Wa~te Management.

U.S. Nuclear Regulatory Commission, 1987a. URFO:TTO, Docket No. 40-8681, 04008681740S. Letter to Umetco Minerals Corporation (J. S. Hamrick) from F. F. Hawkins dated January

26. 1987.

U. S. Nuclear Regulatory Commission, 1987b. IO CFR 40, Appendix A lJ. S. Nuclear Regulatory Commission, 1987c. URFO:GRK, Docket No. 40-8681, Letter to Umetco Minerals Corporation from E F. Hawkins dated October 21, 1987. U. S. Nuclear Regulatory Commission, 1988. Docket No. 40-8681 SUA" 1358, Amendment No. I 0. Letter to Umetco Minerals Corporation dated January 8, 1988, from R. Dale Smith. University of Utah Seismograph Stations, 1988. Computer List of Earthquakes within 320 km of Blanding, Utah, Department of Geology and Geophysics, University of Utah, Salt Lake City. von Hake, C. A., 1977. Earthquake History of Utah, Earthquake Information Bulletin 9, pp. 48-51. Warner, L. A.. I 978. The Colorado Lineament, A Middle Precambrian Wrench Fault System, Geological Society of America Bulletin, v. 89, pp. 161-171. H *,llSl!L1\\WMR{"PI.NIWHIT'!!MMSA IU\\f"\\May 1999

Page \\Xl Revision ~1.0 International l iranium ( l /SA) Corp. white Mesa Mill Reclamation Plan Williams, P l. 1964. Oeology, Structure, and Uranium Deposits of the Moah ()uadrangle. Colorad<> and l rtah, I:. S. Geologic Survey Map, I-360 Witkind, I..I. 1964 Ueology nf the Abajo Mountains Area, San.Juan Countv, ! r1ah. [ 1 S (,co logical Survey. Protcss1onal Paper 45 J. Woodward-Clyde ( 'onsultants, 1982 Oeolog1c Characten,.ation Report of the Paradox Basin Study Region, Utah Study Areas, ONWl-290, v. I, Prerared for Office of Nudear Waste Isolation.. Battelle Memorial Institute. Wong.. l U. 1981. Seismological Fvaluation of the Colorado I meamcnt in the lntermounta111 R,.:gion ( abs L Earthquake Notes, \\. S 1. pp. 1 ~.,4 Wong, I U.. l 984. S1:1srniutv ofthe Paradox Ba.,:n and the ( 'olorado Plateau Interior. ONWl-49.~. Prepared for the ( Hfi...:e of Nuclear Waste (solat1on, Battelle Memorial lnstitutt~ /ohack, M. I>. and Zoback, M I. 1980. State of Stress in the Conterminous l jntted States. Journal of Oeophysical Research, 1, 85. pp. 6113-6156.

Page I-I Revision 2.0 International Uranium ({ lSA) Corp. White Mesa Mill Reclamatiun Plan INTRODl!('.TION This document prepared by International Uranium (USA) Corporation C'IUSA"), presents IUSA's plans and estimated costs for the reclamation of Cells 1-1, 2. J, and 4. and frlf decommissioning of the White Mesa Mitl. The uranium processing sections of the mill will be decommissioned as frlllows: The uranium and vanadium processing areas of the milL including all equipment, strm:tures and support facilities will be decommissioned and disposed of in tailings or buried on site as appropriate. All equipment. including tank.age and piping; agitation; process control instrumentation and switchgears; and contaminated structures; will be cut up, removed, and buried in tailings prior to final cover placement. Concrete structures and foundations will be demolished and removed or covered with soil as appropriate. These decommissioned areas would include, but not be limited to. the following: Coarse ore bin and associated equipment, conveyors and structures. Grind circuit including serni-autogenous grind (SAG) mill, screens. pumps and l.'.ycloncs. f'hree pre-leach tanks to the east of the mill building, including all associated tankage, agitation equipment. pumps, and piping. Seven leach tanks inside the main mill building, including aJl associated agitation equipment pumps and piping. Counter-current decantation ( CCD) circuit including all thickeners and equipment, pumps and pQping. Uranium precipitation ctrcuit, including all thickeners, pumps and piping. J'wo yellowcake dryers and all mechanical and electrical support equipment, including uranium packaging equipment. Clarifiers to the west of the mill building including the preleach thickener and claricone. Boiler and all ancillary equipment and buildings. H IUSU...'I\\ WMR.CPlN\\INTllO llPTIMay I *'l'l'l

Page 1-2 Revision ~ 0 lntemattonal Uranium (USA) Corp White Mesa Mill Redamation Plan Entire vanadium precipitation. drying, and fusion circuit. All external tankage not included in the above list including. reagent tanks for the storage of acid, ammonia, kerosene, water, or dry chemicals; and the vanadium oxidation circuit. Uranium and vanadium sol\\em extraction ( SX) circuit including all SX and reagent tankage. mixers and settlers, pumps, and piping. SX building. Mill building. Office building. Shop and warehouse building. Sample plant building. The sequence of demolition would proceed so as to aHow the maximum use of support areas ot the facility, such as the office and shop areas. It is anticipated that all m~jor structures and larg1.. equipment will be demolished with the use of hydraulic shears. rhese will speed the process. provide proper sizing of the materials to be placed in tailings, and reduce exposure to radiation and other safety haz,ards during the demolition. Any uncontaminated or decontaminated equipment to be considered for salvage will be released in accordance with the NRC document, Qyi~Unes for OeconUY.nination gf facilities ang Egyipmcm Prior to Release f2r U~§tricteg Use.or Termination gJ' Licenses for ByprmJ&lk! Qt S,.uJICe M&teriaJ~, dated September, 1984, and in compliance with the conditions of Source Material License StJA-l 1'.i8. As with the equipment for disposal. any contaminated soils from the mill area will be disposed of in the tailin~s facilities m accordance V\\ltth Section 4.0 of Attachment A, Plans and Specifications. H MSEllS\\ WMXC Pl N\\INTII.O ltPT\\M11y I 9'l<l

Page 1-3 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan The estimated reclamation costs for surety are summarized as follows: White Mesa Reclamation Qirf;ct Cost~ Mill Decommissioning Cell I Reclamation ('r.:11 1 Reclamation Cell 3 Reclamation Cell 4A Reclamation Misc Items (Projed Oeneral) Profit Allowance ( \\mtingency Licen~;ing and Bonding Long Term Care Fund REPORf ORGANIZATION ( 'ost Summary Subtot§l Direct: 10% 15% 2% rota! Surety ReS1uirement 1,505,166 933,169 1,082,869 1,565,444 120.128 l.939,480 il.J46,257 714.626 1.071,939 142.925 606,721 $9.§82.4g7 General site characteris1tcs pertinent to the reclamation plan are l:ontaincd in Set:tion l.O. Descriptions of the facility constrn.ction, operations and monitoring arc given in Section 20 !'he current environmental monitoring program is described in Section 2.l Seismic risk was asscssc:*d in Section 2.6..1. Ibe Reclamation Plan including descriptions of facilities to be reclaimed and design criteria, is presented in Section 3.0. Section.3.0 Attachments A through Hare the Plans and Specifications. Quality Plan for Construction Activities, Cost Estimates, and supplemental testing and design details. Ii 'liSEIUIWMlCPLN\\INTRO RJ>r*Mav 1m

I' i..(i, i./,, \\ i,,,,,, l:iif*tn,!11*,n.,tl',,!filiiln, I "', \\, 1 ,il, \\A iq11 \\h,,i \\1di !fr, 1,iW,lfi*,;, l'Lu

P,t~~* l Nt,hn111 11 hl!l"Hl;'ll!iifl!'ll i llUl!IIW 1! "1 \\, i.,,q, \\Aihih \\At:"1H \\1,H R1*t 11:lOHll!illl !'L11, J fk' ~ ~'WM:WAI, tmwta1i &IN! ha luh lhtHUjh t k.':-t~imt,~n t 1*Nt'l, f I ~ I 1*Nf, i,.,, h:1Ho1.hu.*,l !!I

• \\pf!tu,~n, \\.

,1;.i"'~~utrm '>\\,mu Annwtl I* tllu,mi k.4'1fkirl" tlu,1u,t1 I ~ .. t'mht':l,,i l *J*JK hiH,, ht'l"n 'iUhmlUttrti (H !:ht* NI(( Ill 1,*JtUphillt.i: ""'1th i !,t$Hi!!..: f~14tm~mctiih 1\\<'li,m,,ti th, ~Ul{lhi, lit iht 'Willi

f{t \\ l,,/1 tli 1 1

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I l < I !MAil* Pagel.;; Re\\ 1s1on.' O lnternatmnal I 1rarnum ( l 'SA., ( *orp White Mesa Mill Rcdamatwn Plan I ext,in d1mate and as:,ioc1ated tables are adapkJ. with mrnor re-v,swns. from the hnal I S Ne\\.1. table number~ art:'. added to the text helo\\\\< to correspond tn..,t*ctwns m this Rcch:Um1*111n Plan, hut. tht nriw.mal tahlt! numher-; from the Hnal FS are cited on the modified tables. for t*ase of reterenct' 1\\lthoujh varymj,;omewhat with elevation and tcrram m lhc vicinrty ot the site, the cllmace can generally he descnhed as serniand Skies are usually dear wtth abundant 'lunshme, preup1tatwn i!<> light, hun11d1ty is low.. and evaporation 1s high Daily ranMeS in temperature are relatively largt:.,md winds are normally light to moderate lntluenctis that ""ould result in s;noptlc metcornlc1~1cal condtttons are reiati vel} weak: as a result, t.opo11raphv and lo<.:al m1cromcterolog11.'.al etler.:ts pla'r an important role in determining climate m the region ,casons are well defined m the region Winters arc cold but usually not se\\ere, and summc:rs arc \\\\arm I ht: normal mean mmual temperature reported for Hlanding, I 1tah. is about 'iO r I lo l' L <1s shm,,n in labk I l

• I ( I able 2 I in the Vinal FS i January 1s usually the coldest month m the region, with H normal mt~an monthly h::mp,m.ttun* ot about :. 7 f' (, \\ < ')

temperatures of O 1-i, I K ** ( ') or he low may ou.:ur m about two ut every thrcl* yi"tU's but hm1peratures b~low

• I.5 f, { *.'.o t *) are rare July 1s JiJeneraHy the warmest mo1HlL havmg,i normal mean monthly 1emperaturc ul about 71 F ( 23 ' C) femperatures above 90 F U 2 ( l,m* not un1.:ommon III tht* su,nmcr and arc reported lo occm about 34 days a year; however, temperaturl!s above 100 ' ~* ( \\8 ( *) uu:ur nm:11

112 l~iWU.Qll ( Final ES Section 2.1.2) Page 1-6 Revision 2.0 International l 'ranium (USA) Corp. White Mesa Mill Reclamation Plan Pret:ipitation in the vicinity of the White Mesa I lranium Project is light ( ['able I. I*-~~) ( Final ES rable 2. 2 ). Normal annual precipitation is about 12 inches ( 30 cm). Most precipitation in the area is rainfall. with about 25 percent of the annual total in the form of snowfall. rhere are two separate rainfall seasons in the region.. l'he first occurs in late summer,md early autumn when moisture-laden air masses occasionally move in from the Oulf of Mexico, resulting in showers and thun<lerstonns. rhe second rainfall period occurs durmg the winter when Pacitk stom1s frequent the region 1.1.3 W..inrui (Final FS Section L 1.3) Wind speeds arc generally light to moderate at the site during all seasons, with occasional strong winds during late winter and spring frontal activity and during thunderstorms in the summer. Southerly wind directions are reported to prevail throughout the year. 1.1 4 t2wnns (Final ES Section 2.1.4) I'hunderstorms are frequent during the summer and early fall when moist air moves into the area from the Oulf of Mexico. Related precipitation is usually light, but a heavy local storm can produce uver an inch of rain in one day. The maximum 24-hour precipitation reported lo have fallen during a 30-*year period at Blanding was 1.98 inches (5.02 cm). Hailstorms are uncommon in this area. Althoujh winter storms may occasionally deposit compuable amounts of moisture, maximum short-term precipitation 1s usually associated with summer thunderstorms.

Page I~ 7 Revision 2.0 fntemational Uranium (USA) Corp. White Mesa Mill Reclamation Plan rornadoes have heen observed in the general region. but they occur infrequently. Strong winds can rn.:cur in the area along with thunderstorm activity in the spring and summer. rhe White Mesa site is susceptible to dccasional dust storms, which vary greatly in intensity. duration. and time of occurrence. rhe basic Londitions fi)r blowing dust in the region are created by wide areas of exposed dry topsoil and strong. turbulent winds. Dust storms usually occur following frontal passages during the warmer months and are occasionally associated with thunderstorm activities. fl,l_:.~ERS1WMIICPt. N'.SE( Tll I RPr,May 1-l<l'l

TABLE l.I-l Temperature means and extremes at Blanding, Utah" Means Extremes Daily Daily Record Record Month maximum mm1mum Monthly highest Year lowest Year (;c OF oc OF oc OF oc OF "C "'F January 3.9 39.1 -9. l 15.6 -2.6 27.4 16 60 1956 -27 -17 1937 February 6.5 43.7 -6.4 20.4 O.l

32. l 19 67 1932

-31 -23 1933 March 11.1 51.9 -3.3

26. I 3.9 39.0 22 72 1934 17

'1 1948 April 1,.O 62.6 0.9 33.7 8.9 48.l 28 82 1943 12 I l 1936 May 22.2 7!.9 5.2 41.3 13.7 56.6 33 92 195 l -5 23 1933 June 28.2 82.8 9.6 49.2 18.9 66.0 38 IOO 1954 28 1947 July 31.7 89.I 13.8 56.9 27.8 73.0 39 !03 1931 '1 36 1934 August 30.3 86.5

13. I 55.5 21.7 71.0 37 98 1954 6

42 1950 September 26.2 79.3 8.7 47.7 17.6 63.6 35 95 1948 -2 29 1934 October 19.0 66.2 2.7 36.9 10.9 51.6 .. ') 90 1937 -JO 14 1935 November 10.4 50.8 -4.4 24.l

3. l 37.5 21 69 1934

-22 -7 1931 December 5.3 41.6 -7.4 18.6 I.I 30,) 16 61 1949 -24 - l l 1935 Annual 17.7 63.8 1.9 35.5 9.8 49.7 39 103 July 1931 -31 -23 February 1933

• Period of record: 1931-1960 (30 years).

Source: Adapted from U.S. NRC (1979) Final Environmental Statement, Page 2-2, Table 2.1. Original Source: Plateau Resources. Limited, Application for Source Material License, Table 2.2-1, p. 2-6, Apr. 3. 1978.

TABLE l.l-2 Precipitation means and extremes at Blanding, Utaha Total Month Mean monthly Maximum monthly Greatest daily Year cm

m.

cm

m.

cm

m.

January 3.04 1.20 10.31 4.06 2.64 1.04 1952 February 2.95 1.16 4.39 1.73 2.62 1.03 1937 March 2.38 0.94 5.00 1.97 2.54 1.00 1937 April 2.18 0.86 5.41 2.13 2.69 1.06 1957 May 1.63 0.64 5.11 2.01 2.39 0.94 1947 June 1.39 0.55 5.51 2.17 3.56 1.40 1938 July 2.13 0.84 7.79 3.07 3.35 1.32 1930 August 3.02 l.19 12.59 4.96 5.03 1.98 1951 September 3.02 1.19 9.60 3.78 3.07 l.21 1933 October 3.5 J 1.38 16.79 6.61 3.94 l.55 1940 Novembt:r 1.88 0.74 5.21 1.05 2.41 0.95 1946 December 3.20 1.26 9.29 3.66 3..56 1.40 1931 3Period of record: l 93 l-1960 (30 years). Source: Adapted from U.S. NRC ( 1979) Final Environmental Statement, Page 2-2, Table 2.2. Original Source: Plateau Resources, Limited, Application for,S'uurce Ma1erial License. Table 2.2-2, p. 2-8. Apr 3, 1978.

1.2 TOPOGRAPHY Page 1-10 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan The following text is reproduced from Section 2.3 of the Final ES. The site is located on a "peninsula" platform tilted slightly to the south-southeast and surrounded on almost all sides by deep canyons, washes, or river valleys. Only a narrow neck ofland connects this platform with high country to the north, fom1ing the foothills of the Abajo Mountains. Even along this neck, relatively deep stream courses intercept overland flow from the higher country. Consequently, this platform (White Mesa) is well protected from runoff flooding, except for that caused by incidental rainfall directly on the mesa itself. The land on the mesa immediately surrounding the White Mesa site is relatively flat. 1.3 ARCHEOLOGICAL RESOURCES The following discussion of archeological sites is adapted from Section 2.5.2.3 of the Final ES. 1.3. l Archeological Sites Archeological surveys of portions of the entire project site were conducted between the fall of 1977 and the spring of 1979. The total area surveyed contained parts of Section 21, 22, 27, 28, 32, and 33 of T37S, R22E, and encompassed 2,000 acres (809 ha), of which 200 acres (81 ha) are administered by the U.S. Bureau of Land Management and 320 acres (130 ha) are owned by the State of Utah. The remaining acreage is privately owned. During the surveys, 121 sites were recorded and all were determined to have an affiliation with the San Juan Anasazi who occupied this area of Utah from O A.O. to 1300 A.O. All but 22 of the sites were within the project boundaries. H IUSERS\\WMRCPL!'/ISECTOI RPT\\May 1999

Page l-11 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan Table 1.3-1, adapted from Final ES Tvble 2.18, summarizes the recorded sites according to their probable temporal positions. The dates of occupation are the best estimates available, based on professional experience and expertise in the interpretation of archeological evidence. Available evidence suggests that settlement on White Mesa reached a peak in perhaps 800 AD. Occupation remained at approximately that kvel until some time near the end of Pueblo II or in the Pueblo II/Pueblo III transition period. After this period, the population density declined sharply, and it may be assumed that the White Mesa was, for the most part, abandoned by about 1250 A.O. Archeological test excavations were conducted by the Antiquities Section, Division of State History. in the spring of 1978, un 20 sites located in the area later to be occupied by tailings cells 2, 3 and 4. Of these sites, 12 were deemed by the State Archeologist to have significant National Register potential and four possible significance. The primary detenninant of significance in this study was the presence of structures, though storage features and pottery artifacts were also common. In the fall of 1978, a surface survey was conducted on much of the previously unsurveyed portions of the proposed mill site. Approximately 45 archeological sites were located during this survey, some of which are believed to be of equal or greater significance th.m the more significant sites form the earlier study. Detennination of the actual significance of all untested sites would require additional field ~nvestigation. H 'USEJlSIWMRCPLN\\SECTOI RP1'.M1y 1999

TABLE 1.3-1 Distribution of Recorded Sites According to Temporal Position "!"emporal position Approximate dates (A.D.)a Number of sites Basket Maker III 575-750 Basket Maker Ill/Pueblo I 575-850 27 Pueblo I 750-850 12 Pueblo I/Pueblo II 850-950 13 Pueblo II 950-1100 14 Pueblo II/Pueblo III I I 00-1150 12 Pueblo III 1150-1250 8 Pueblo II+ b 5 Multicomponent C 3 Unidentified d 14 a Includes transitional periods. b Although collections at these locations were lacking in diagnostic material. available evidence indicates that the site would have been used or occupied no earlier than 900 A.O. and possibly later. c Ceramic collections from each of these sites indicate an occupation extending from Pueblo I through Pueblo II and into Pueblo Ill. d These sites did not produce evidence strong enough to justify any identification. Source: Adapted from Dames & Moore (1978b) (ER), Table 2.3-2, U. S. NRC (1979) Final Environmental Statement, Page 2-20, Table 2. I 8, and from supplementary reports on project archeology.

Page 1-13 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan Pursuant to l O CFR Part 63.3, the NRC submitted on March 28, 1979, a request to the Keeper of the National Register for a determination of eligibility for the area which had been surveyed and tested. The area contained 112 archeological sites and six historical sites. The determination by the Keeper of the National Register on April 6, 1979, was that the White Mesa Archeological District is eligible for inclusion in the National Register. l.3.2 Current Status of Excavation Archeological investigations for the entire mill site and for Cells 1-I through Cell 4 were completed with the issuance of four separate reports covering 30 sites, excluding re-investigations. (Lindsay 1978, Nielson 1979, Casjens et al 1980, arid Agenbroad et al 1981 ). The sites reported as excavated are as follows: 6380 6381 6384 6385 6386 6387 6388 6391 6392 6393 6394 6395 6396 6397 6403 6404 6420 6429 6435 6436 Sites for which excavation has not been required are: H IUSERS\\WMllCPLNI.SECTOl 11.P1'1May 1999 6437 6684 6685 6686 6697 6698 6699 6754 6757 7754

1.4 6379 6382 6405 6441 6443 6444 7658 7659 7660 The sites remaining to be excavated are ( continued): 6408 6445 7661 6421 6739 7665 6427 6740 7668 6430 7653 7675 6431 7655 7684 6432 7656 7687 6439 7657 7689 SURF ACE WATER Page 1-14 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan 7690 7691 7693 7696 7700 7752 7876 8014 The follo\\.\\ing description of undisturbed surface water conditions is adapted from Section 2.6. l of the Final ES. Since construction, the mill has been designed to prevent runon or runoff of storm water. No perennial surface water drainages exist on the site. The description of surface water quality in subsection 1.4.2 reflects baseline sampling performed in July 1977 - March 1978. Continuous monitoring of surface water is not possible due to lack of streamflow. 1.4. l Surface Water Description (Final ES Section 2.6. l. l) The mill site is located on White Mesa, a gently sloping ( l % SSW) plateau that is physically defined by the adjacent drainages which have cut deeply into regional sandstone formations. There is a small drainage area of approximately 62 acres (25 ha) above the site that could yield surface runoff to the site. Runoff from the project area is conducted by the general surface topography to either H '.USERSIWMRCl'LN\\SECTOI Rl'l\\May 1999

Page 1-15 Revision 2. 0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan Westwater Creek, Corral Creek, or to the south into an unnamed branch 0fCottonwood \\Vash. Local porous soil conditions, topography and low acreage annual rainfall [ l l.8 inches :.30 cm)] cause these streams to be intermittently active, responding to spring sno\\\\-melt and local rainstorms (particularly thunderstorms). Surface runoff from approximately 384 acres ( 155 ha) of the project site drains westward and is collected by Westwater Creek, and runoff from another 384 acres ( 155 ha) drains east into Corral Creek. The remaining 713 acres (289 ha) of the southern and southwestern portic,us of the site drain indirectly into Cottonwood Wash (Dames & tvfoore, 1978b, p. 2-143 ). The site and vicinity drainages carry water only on an intermittent basis. The major drainages in the proje~t vicinity are depicted in Figure 1.4-l and their drainages tabulated in Table 1.4-1. Total runoff from the site (total yield per watershed area) is estimated to be less than 0.5 inch (1.3cm) annuaily (Dames & Moore, 1978b, p. 2-143 ). There are no perennial surface waters on or in the vicinity of the project site. This is due to the gentle slope of the mesa on which the site is located, the low average annual rainhll of 11.8 inches (29. 7 cm) per year at Blanding (Dames & Moore, 1978b, p. 2-168), k,cal soil cl;aracteristics and t~1e porous nature of local stream channels. Prior to construction, three small ephemeral catch basins were present on the site to the northwest and northeast of the scale house. Corral Creek is an intermittent tributary to Recapture Cre1;.J. The drainage area of that portion of Corral Creek above and including drainage from the eastern portion of the ~ite is about 5 square miles (l 3 km2). Westwater Creek is also an intennittent ttibutarj of Cottonwood Wash. The Westwater Creek drainage basin covers nearly 27 square miles (70 km2) at its confluence with Cottonwood Wash 1.5 miles (2.5 km) west of the project site. Both Recapture Creek and Cottonwood Wash are similarly intermittently active, although they carry water more often and for longer periods of time due to their larger watershed areas. They both drain to the south and are H IUSE1lS1WMRCPLN\\SECTOI RP1\\M.ly IQ<J<J

Page l-16 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan tributaries of the San Juan River. The confluences of Recapture Creek and Cottonwood Wash with the San Juan River are approximately 18 miles (29 km) south of the project site. The San Juan River, a major tributary for the upper Colorado River, has a drainage of 23,000 square miles (60,000 km2) measured at the USGS gauge to ihe west of Bluff, Utah (Dames & Moore, 1978b, p. 2-130). If \\USERSIWMRCPlN\\SEC"fOI RPT.',1ay 1999

USGS USGS USGS GAUGE GAUGE GAUGE NO. 09376900 NO. 09378630 NO. 09378700 \\.

• International Uranium (USA) Corporation White Mesa Mill DESJGN:

CHKD BY: APP: FIGURE 1.4-1 Drainage Map of the Vicinity of the White Mesa Mill DRAWN: RAH DATE: MAY, 1999 SCALE:AS SHOWN SHEET of

TABLE l.4-1 Drainage Areas of Project Vicinity and Region Drainage area Basin description km~ sq. miles Corral Creek at co~1tluence l 5.0 5.8 with Recapture Creek Westwater Creek at confluence 68.8 26.6 with Cottonwood Wash Cottonwood Wash at USGS <531 <205 gage west of project site Cottonwood Wash at confluence <860 <332 with San Juan River Recapture Creek at USGS gage 9.8 3.8 Recapture Creek at confluence <518 <200 with San Juan River San Juan River at USGS gage <60,000 <23,000 do-wnstream at Bluff, Utah Source: Adapted from Dames & Moore (1978b), Table 2.6-3

Page 1-19 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan Storm runoff in these streams is characterized by a rapid rise in the flow rates, followed by rapid recession primarily due to the small storage capacity of the surface soils in the area. For example, on August 1, I 968, a flow of 20500 cfs (581 m3/sec) was recorded in Cottonwood Wash near Blanding. The average flow for that day, however, was only 4,340 cfs ( 123 m3/sec). By August 4, the flow had returned to 16 cfs (0.5 m3/sec) (Dames & Moore, 1978b, p. 2-135). Monthly strearnflow summaries are presented in Figure l.4-2 for Cottonwood Wash and Recapture Creek. Flow data are not available for the two smaller water courses closest to the project site, Corral Creek and Westwater Creek, because these streams carry water infrequently and only in response to local heavy rainfall and snowmelt, which occurs primarily in the months of April, August, and October. Flow typically ceases in Corral and Westwater Creeks within 6 to 48 hours after precipitation or snowmelt ends. 1.4.2 Surface Water Quality (Final ES Section 2.6. l.2) Sampling of surface water quality in the project vicinity began in July 1977 and continued through March 1978. Baseline data describe and evaluate existing conditions at the project site and vicinity. Sampling of the temporary on-site surface waters (two catch basins) has been attempted but without success because of the lack of naturally occurring water in these basins. The basin to the northeast of the mill site has been filled with well water to serve as a nonpotable water source during construction of office and laboratory buildings in conjunction with the mill (approximately six months). This water has not been sampled but presumably reflects the poor quality associated with locai groundwater. Sampling of ephemeral surface waters in the vicinity was possible only during major precipitation events, as these streams are normally dry at other times. H IUSERS\\WMllCPLN\\Sl!('TOI RPT\\May 1999

Page 1-20 Revision 2. 0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan The locations of the surface water sample sites are presented in Figure 1.4-3. The water quality values obtained for these sample sites are given in Dames & Moore (1978b) Table 2.6-7, and U.S. NRC ( 1979) Table 2.22. Water quality samples were collected during the spring at several intermittently active streams that drain the project area. These streams include Weshvater Creek (S 1 R, S9) Corral Creek below the small irrigation pond (S3R), the junction of Corral Creek and Recapture Creek (S4R), and Cottonwood Creek (S8R). Samples were also taken from a surface pond southeast of the mill (S5R). No samples were taken at S2R on Corral Creek or at the smaJI wash (S6R) located south of the site. Surface water quality in the vicinity of the mill is generally poor. Waters in Westwater Creek (SIR and S9) were characterized by high total dissolved solids (TDS; mean of 674 mg/liter) and sulfate levels (mean 117 mg of S04 per liter). The waters were typically hard (total hardness measured as CaC03; mean 223 mg/liter) and had an average pH of 8.25. Estimated water velocities for Westwater Creek averaged 0.3 fps (0.08 m/sec) at the time of sampling. H IUSERS\\WMRCPLN\\SECTOI RJ'l\\May 1999

'lflll-'.t;,.~.,,,~..,..-* I-LiJ LiJ LI.. I LAJ a: u < 3 0 ...J LI.. ...J

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E LiJ c.D C( a:: LIJ C( 400 350 300 250 200 150 100 50 350 300 250 200 150 100 50 AVERAGE ANNUAL FLOW=BOOAF-(1965-1974) DRAINAGE AREA=3.77 SQ. MI. AVERAGE ANNUAL YIEL0=212.2 AF/SQ. MI. YIELD-AF/SQ. MI MIN. AVE.

MAX, 26

{1970) 212 OCT NOV DEC JAN FE.B MAR APR MAY JUNE JULY AUG SEPT MONTH RECAPTURE CREEK NEAR BLANDING USGS GAUGE 09378630 AVERAGE ANNUAL FLOW=734 AF {1965-1971) DRAINAGE AREA=4.95 SQ. MI. AVERAGE ANNUAL YIELD=148 AF/SQ. MI. 862 (1972) YIELD-AF/SQ. MI. MIN. AVE. MAX. 47.1 148 (1970) - ~ OCT HDV DEC JM\\I FES MAR.APR MAY JU£ Jll. Y AUG SEPT MONTH SPRING CREEK ABOVE DIVERSIONS, NEAR MONTICELLO USGS GAUGE 09376900 281 (1965) llillkr:1t,,1t*~... _________________________________

1600 1400 w w -~ 1200 ~ u ~ 1000

a 0

...J 800 X ~ 600 0 £" AVERAGE ANNUAL FLOW=6300 AF (1964-1974) DRAINAGE AREA=205 SQ. MI. AVERAGE ANNUAL YIELD= 31 AF/SQ. MI. YIELD-AF/SQ. MI. MIN. AVE. MAX.

6. 7 31 100 (1969}

(1972) r ~ 2001 ,-......,,~...,,-.,.., -,-, ~,,--...,..,-.,.., -...., -...., -----...... OCT NOV DEC JAN FEB MAR APR MAY ~ JU.. Y AUG SEPT MONTH COTTONWOOD WASH NEAR BLANDING USGS GAUGE 09378700 NOTES

1. FOR THE LOCATION OF W1'TERCOURCES SUMMARIZED, SEE PLATE

2. SOURCE OF DATA. WATER RESOURCES DATA RECORDS.

COMPILED ANO PUBLISHED BY USG S APERTURE CARD International Uranium (USA) Corporation White Mesa Mill FIGURE 1.4-2 Stream Flow Summary in the Vacinity of Blanding, Utah E GN: SHEET CHKO BY: ot APP: SCALE:AS SHOWN

'~ ~J,:,,:' --~t,*I* N... . \\. J ~.. - ( I i' Jf SAIPLINI STATIONS IN PROJECT VICINITY G*.._ GROUNDWATER (WELL OR SPRJNGl S A MP L I N G L O C A r I O N -L')

• ~ S. SUR F A C E W A T E R S A M PL I N G

1. Oi.:ATION SAMPLING 0 r~ A r I OQN t 1

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Page l -23 Revision 2. 0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan Samples from Cottonwood Creek (S8R) were similar in quality to Westwater Creek water samples, although the TDS and sulfate levels were lower cros averaged 264 mg/liter; so, averaged 40 mg/liter) during heavy spring flow conditions [80 fps (24 m/sec) water velocity]. The concentrations ofTDS increased downstream in Corral Creek, averaging 3,180 mg/liter at S3R and 6,660 mg/liter (one sample) at S4R. Total hardness averaged in excess of 2.000 mg/liter, and pH values were slightly alkaline. Estimated water velocities in Corral Creek were typically less than 0.1 fps (0.03 m/sec) during sampling. l'he spring sample collected a the surface pond south of the project site (S5R) indicated a TDS concentration of less than 300 mg/liter. The water was slightly alkaline with moderate dissolved sulfate levels averaging 42 mg/liter. During heavy nmoff, the concentration of total suspended solids in these streams increased sharply to values in excess of 1,500 mg/liter (lJ,S. NRC 1979, Table 2.22). High concentrations oft:ertain trace elements were measured in some sampling areas. Levels of mercury (total) were reported as high as O 002 mg/liter (S3R, 7/25/77: S8R, 7/25/77). fotaJ iron measured in the pond (SSR. I I/ I 0/77) was 9.4 mg/liter. These values appear to reflect groundwater quality in the vicinity and are probably due to evaporative concentration and not due to human perturbattun of the environment 1.5 GROUNDWATER The following descriptions of groundwater occurrence and characteristics in and around the White Mesa Mill is a summary and compilation of information contained in documents previously submitted to and reviewed by the U.S. NRC. These include the Final ES, the HygroiieQloaic ft,usEllSIWMJlCPLN\\SECTOI Rif\\M1y IY9'1

Page 1-24 Revision 2.0 International l)ranium (USA) Corp. White Mesa Mill Reclamation Plan EvalY.3tiQn of White Mc§a Urnni.um MiU (Hydrogeologic Evaluation> (Titan. 1994a). Points of CompHwice. WbiteM~UraniumMiU ("POC")(Titan, I 994b), the Semi-Annual fiftluent Report's through December 1998. The Hydrogeologic Evaluation referenced numerous technical studies: Regional geologic and geohydrologic data were obtained primarily from U.S. Geologic Survey ((J.S.G.S.) and State oflJtah publications; Site-specific information was obtained from the 1978 Environmental Report ( Dames & Moore); a 1992 groundwater study report submitted to the NRC by Umetco: a 1991 groundwater hydrology report on White Mesa prepared by Hydro-Engineering; and reports by D' Appolonia ( 1981. 1982, and 1984). See the Hydrogeologic Evaluation, transmitted herewith in its entirety as Appendix B. for complete data tables, lists of references, and technical details described in this section. This section is primarily an adaptation of the HydrogeoJogic Evaluation. For ease of refcrem:c, a copy of the Hydrogeologic Evaluation is included as Appendix B previously submitted to the NRC. The POC is included as Appendix C also previously submitted. The Hydrogeologic Evaluation focused on description and definition of the site hydrostratigraphy, and occurrence of groundwater as it relates to the natural and manmade safeguards which protect groundwater resources from potential leakage of tailings cells at the site. The POC summarized and statistkally analyzed the available groundwater database, and proposed a revised groundwater monitoring and data review program. The findings of the Hydrogeologic Evaluation indicated that the tailings located in the existing disposal cells are not impactina growidwater at the site. In addition, it does not appear that future impacts to groundwater would be expected as a result of continuing operations. II \\USDSIWMll(PLN\\Sl:.CTOI IU'TIM.ly 1\\199

Page l *.~:; Revision 2 0 International l 'ranium ( I ISA l ( 'orp White Mesa Mill Rcclamat1on Plan lhcsc condu:,inns are based on i.:hemkal and hvdrngeologit: data whKh -;hm\\ that I he chcmistr\\ nf perched groundwater cncuuntcred hclP\\1,, lht: Sitt',illli not,,ho\\\\ 1*om.*cntrnt1011s nr nirn'asing trends in L'nrn.*cntrntion, 11t cnnst1t1w11ts that \\V11uld 1ndicatt~ scepagt: from the existing dispo\\al cells, 'i. I ht' ust.~ahle a4u1frr 1*; undt:r artt'si;m prcssun: and. therefore. has,ltl upv,ard pn..'sstm* 4 gradient which \\VtHJld prcdudc do,\\nward migrnllon olnmst1tucnts 11H11 the aquifer. mid I ht* tai..:tl1ty has operated for a pcnod 1ll I 11 year:,;,md has c,nhed nu,.bnirrnhk 11npaus tu groundwater during ttus period. l 'nntinut:d munttonng of gniundwt1k1 at th,: Sitt' an: pt~rformcd to ven ty that past. current. mid i uturc npt*nu10ns v;tl I not impact groundwater I tw t'X 1-.;ling momlormg prngrarn,md re:,:;ul.ts are pn:scnk*d m the Semi annual Fftluent reports which ari: regular!\\ *mhnuttt:d lo ttw r,~R<

1.5. l Page 1-26 Revision 2.0 lntemational Uranium (USA) Corp. White Mesa Mill Reclamation Plan As shown on Hgure 1.1-2, White Mesa Uraniwn Mill is located in southeastern Utah, approximately six miles south of the town of Blanding. It is situated on \\\\rhite Mesa, a tlat area bounded on the east by Corral Canyon, to the west by Westwater Creek, and to the south by Cottonwood Canyon. The site consists of the uranium processing mill, and four engineered lined tailings disposal cells. I t:, G' l..., .. ).,~. eo oa1c ;;~ttma The White Mesa Uranium Mill site is located near the western edge of the Blanding Basin within the Canyon Lands section of the Colorado Plateau physiographic province (Figure 1.5-1. Hydrogeologic Evaluation Figure I. I). The Canyon Lands have undergone broad, fairly horizontal uplift and subsequent erosion which have produced the region's characteristic topography represented by high plateaus, mesas, buttes and deep canyons incised into relatively flat lying sedimentary rocks of pre~Tertiary age. Elevations range from approximately 3,000 feet in the bottoms of the deep canyons along the southwestern margins of the region to more than 11,000 feet m the Henry, Ab~jo and La Sal mountains located to the northwest and northeast of the facility. With the exception of the deep canyons and isolated mountain peaks, an average elevation slightly in excess of 5,000 foet persists ovet most of the Canyon Lands. fhe average elevation at the White Mesa Uraniwn Mill is 5,600 feet mean sea level (MSL).

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Page 1.. w k.e\\.1S1on.~ 0 International I :rnmum I trSA) Corp White Mt~a Mill Reclamatwn Plan rhe,trat.a underlying White Mesa have a re1ional dtp nf I 2 to I deyrees to tht: '!outh. however. lo(:al dips of 'i degrees have been rm:uured Haynes, et al ( 147 2 I mdudc:s a map shn\\\\-tn~ thr stnu.:tun.~ al the oa.,t* ot the Dakota fonnat1on Apprrnumah~h.:!'\\ tmles to thf nnrth. the *\\ha10 Mountarns. hmneJ hy igneous intrusions. have,:aused lm:al faultmg. upwarpinij. and ~tbplaccnwnt of the ~edimefllary wction. However. mi taults have been mapped in the immediate \\ 11.:in1t\\ ot White Mesa ( )u a re11wm1I huis. the fr)rmations that are re,oynn:ed as aquihm, W't ( *retaceous"aje Dakota Sandston4! and the upper part of the Morrison formation off ate fura.~stc.: a1e. the l* ntrada Sandstont\\ a,ld thte Nav,uo Sandstone of Jurwum: a(ltL the W1n1a1e Sandstone and the Shmarump Member ot the ( 'hmle formation tlf lriu.'.l.ic qe, and the [)eChelle Member of the l *utler formation of Permian auc Recharge to aqu1ters m the reghm occurs h)' mfiltratton of predpitat1on mto th,: aqu1fors alnn~ th~ tlanks,1f the Abi,JO. Henr} a.nd I.a Sal Mountams and along the tlanks l,t' folds, :-iu":h as ( 'omb Ridge Monochntl: and the San Rafael SwelL where the permeable formations are exposed at the '.iurface ( Hau.re I, I. rlydro1eoloa14:.. :vaJuauon Fiaurc I I ) Seventy.,s,x grmmdwater appropriatton applications. within a flvewn\\lle radius uf the Mill site..:Ut' on tile with the l l1-t State Enainoer's offic~ A swnmac; of the apphcations 1s presented in fabk I.1~ I and ihown 011 Ft1we 1 5 1 The m4\\iority of the appliGations is by pnvate individuais and for weUs drawin1 small. intem1tttent qwmtities of water. less than tight gpm, from the Burro< 'any on thrmahon For the most pan, these wells are located up1radient (north) of the White Mesa l Jranium

Page I. l I Re\\ is ion ~1 O International (:ranium (l ISA) ( orp White Mesa Mill Reclamation Plan MIii s1k 'ttock\\.\\'ak*rmg and 1rrigat1on,m: listed as pnma.n, uses nt the rna1onty ot the wells It is important to note that no wells..:ompleted in the perched groundwater of the Burro < 'anyon formation ~x,st <lire1..*tlv downgrnd1cnt ofthe,;1tt;' within the five,rnile radius. I wn \\\\<tiler \\\\ells \\Vht(h avmlahlc data mdt<.:atc are completed in the Fntrada!NavaJo sandstone i('h>""'* 1997) exist approximate!)' 4 " miles southeast,,f the site on the I 1tc Mountain lite Reservation. lhese wells 'iUpph dnmesth.'. water for the t. ltc Mmmta111 I 1te White Mesa ( 'ommunity,,ituated on the n1es,1 alont,; Highway 191 ( 'ice l* igurt' I 4i '1 I >ata supplied hv the I ribal bn 1ronmenta1 Programs< >ftki: indicatt~ that hoth wells arc cnmpleted in the Fntrada;Navajo sandstone. whtt:h 1s approxmrntel) I )00 tt~et helm," tht~ ground ;;urlat:e lnsutlk1ent da1a arc available tl) defini: the groundwater tlov. dtret:t1on 111 the Entrada/Navc1;10 sandston1;~ in the vH.::trnt\\ ot the rntll.

DOCUMENT PAGE(S) PULLED SEE APERTURE CARD FILES APERTURE CARD/PAPER COPY AVAILABLE THROUGH NRC FILE CtNTER NUMBER OF OVERSIZE PAGES FILMED ON APERTURE CARD(SJ / ACCESSION NUMBERS OF OVERSIZE PAGES: .1.. 1_<:2_r;, __ f~_ 0 lb~*-* __ {);;_ ______................. ---*****--*-*---

Table t.5-1 Wells Located Within A 5-Mile Radius of The White Mesa Uranium Mill Map Water Right SE(' TWP RNG CFS USE Depth No. (ft.) Nielson, Nonnan and Richard C II 37S 22E 0.0 IS IDS 150-200 1 Guymon, Willard M. 10 17S 22E 0.015 s 82 ) Nielson, J Rex IO J7S 22l 0 015 IDS 160 4 Nielson. J. Rex I 0 ~7S 22E 0.013 s 165 5 I.yman, Fred S. 10 37S 22E 0.022 IDS 120 6 Plateau Resources 15 37S 22E 0.015 0 740 7 Plateau Resources 15 37S 22[ 0 015 () 1]5 8 Nielson, Nonnan and Richard C' 14 J7S 22E 0.015 IS 150-200 9 I yman, Ueorge F 15 37S 22E 0.015 s 135 10 Holt, N E, Mc Laws, W 15 37S 22E 0.007 s 195 II Perkins. Dorothy 21 37S 22E 0.015 s 150 12 Energy Fuels Nuclear, Inc 2 l 37S 22E 0.6 0 1600 I 1 Energy Fuels Nuclear. Inc. 22 37S 22E I. 11 0 1820 14 I ltah Launch Complex 27 J7S 22E 0.01 S D 650 IS Fnergy Fuels Nuclear, Inc. 28 J7S 22E I.I I 0 1885 16 Energy Fuels Nuclear, Inc. 28 J7S .22E I.I I 0 1850 17 Energy Fuels Nuclear, Inc. 28 J7S 22E 0.015 DSO 1800 18 Energy Fuels Nuclear, Inc. 28 J7S 22E 0.6 0 1600 19 Jones, A Ima U 33 37S 22E 0.015 s 200 20 Energy Fuels Nuclear, Inc. 33 37S 22E 0.6 0 1600 21 BLM 8 37S 22E 0.01 s 170 2.2 Halliday, Fred L 11 37S 22E 0.015 IS 180 2J Perking, Paul 2 37S 22E 0.015 ID 180 24 Redd, James D. 2 37S 22E

0. I ID 200 25 Brown, Aroe G 37S 22E 0.015 IS 210 26 Brown, George 37S 22E 0.015 IDS 140

Table l.5-1 Wells Located Within A 5-Mile Radius of The White Mesa Uranium Mill (continued) Map Water Right SEC TWP RNG CFS USE Depth No. (ft.) 27 Brown, Lio M. 37S 22E 0.004 IDS 141 28 Rentz, Alyce M. 37S 22E 0.015 ID 180 29 Rogers, Clarence 2 37S 22E 0.015 s 142 30 Perkins, Dorothy 37S 22E 0.015 s 100-200 31 Brandt J.R. & C.J. 37S 22E 0.015 IDS 160 32 Montella. Frank A. 3 37S 22E 0.015 IDO 190 33 Snyder, Bertha 37S 22E 0.1 IDS 196 34 Martineau, Stanley D. 37S 22E 0.015 ID 160 35 Kirk, Ronald D. & Catherine A. 37S 22E O.Ql5 IDS 160 36 Palmer, Ned J. and Marilyn 37S 22E 0.015 IDS 0 37 Grover, Jess M. 37S 22E 0.015 s 160 38 Monson, Larry 37S 22E 0.015 IDS 140 39 Neilson, Norman and Richard 37S 22E 0.015 IS 132 40 Watkins, Henry Clyde 37S 22E 0.015 IS 150 41 Shumway, Glen & Eve 15 37S 22E 0.015 IS 60 42 Energy Fuels Nuclear, Inc. 21 37S 22E 0.600 0 1600 (not drilled) 43 Energy Fuels Nuclear, lni.: (#I) 28 37S 22E 1.100 0 1860 44 Watkins, Ivan R. 37S 221: 0.200 s 185 45 Waukesha of Utah 3 37S 22E 0.015 D 226 46 Simpson, William 3 37S 22E 0.030 ID 180 47 Guyman, Willard M. 37S 22E 0.030 s 164 48 Harrieson, Lynda 2 37S 22E 0.012 IDS 49 Hurst, Reed 2 37S 22E 0.015 D 100-300 50 Kaer, Alvin 2 37S 22E 0.015 IDS 100-300 51 Heiner, Gerald 8. 2 37S 22E O.oJ5 ID 75 52 Laws, James A. 2 37S 22E 0.015 IDS 100-300

Table 1.5-1 Wells Located Within A 5-Mile Radius of The White Mesa Uranium Mill (continued) Map Water Right SEC TWP RNG CFS USE Depth No. (ft.) 53 Laws, J. Parley 2 37S 22E 0.015 IDS 54 Anderson, Dennis & Edith 2 37S 22E 0.015 IDS 160 55 Guymon, Eugene 2 37S 22E 0.100 IDS 130 56 Guymon, Eugene 2 37S 22E 0.015 s 130 57 Guymon, Dennis & Doris 2 37S 22E 0.030 IDS 210 58 Guymon, Eugene ') 37S 22E 0.1 i 5 ms 100-200 59 Guymon. Eugene 2 37S 22E 0.115 IDS 100-200 60 Perkins, Dorothy 2 37S 22E 0.015 IDS 140 61 Watkins, Ivan R. 37S 22E 0.015 IDS 145 62 Roper, Lloyd 34 36S 22E 0.015 ID 180 63 Smith, Lee & Marylynn 34 36S 22E 0.060 IDS 170 64 McDonald, Kenneth P. 34 36S 22E 0.015 IDS 734 65 Brake, John 34 36S 22E 0.015 ID 250 66 Brake, John 34 36S 22E 0.015 IS 150 67 Redd, Parley V. & Reva V. 34 36S 22E 0.015 IS 200 68 C & C Construction 34 26S 22E 0.015 IS 190 69 Guymon, Dean W. 3 37S 22E 0.015 IDS 180 70 Phillips, Elizabeth Ann Hurst 34 36S 22E 0.015 165 71 Howe, Leonard R. 3 37S 22E 0.015 0 160 72 Shumway, Mark Eugene 3 37S 22E 0.015 ID 73 Shumway, Mark Eugene 3 37S 22E 0.015 IDS 150 74 Lyman, Henry M. 3 37S 22E 0.100 IDS 200 75 Uta Mountain Ute 23 38S 22E 0.535 D 76 Ute Mountain Ute 23 38S 22E 0.1606 D 1515 ~ D-Domestic 0 - Industrial RNG

• Range I - Irrigation SEC - ~,ection CFS
• Cubic Feet Per Second S - Stockwatering TWP - Township

Page 1-36 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan The well yield from wells completed in the Burro Canyon formation within the White Mesa site is generally lower than that obtained from wells in this formation upgradient of the site. For the most part, the documented pumping rates from on-site wells completed in the Burro Canyon formation are less than 0.5 gpm. Even at this low rate, the on-site wells completed in the Burro Canyon formation are typically pumped dry within a couple of hours. This low productivity suggests that the White Mesa Uranium Mill is located over a peripheral fringe of perched water; with saturated thickness in the perched zone discontinuous and generally decreasing beneath the site, and with conductivity of the formation being very low. These observations have been verified by studies performed for the U.S. Department of Energy's disposal site at Slick Rock, which noted that the Dakota Sandstone, Burro Canyon forrnation, and upper claystone of the Brushy Basin Member are not considered aquifers due to the low permeability, discontinuous nature, and limited thickness of these units (U.S. DOE, 1993). l.5.3. l Hydrostratigraphy The site stratigraphy is described above in Section 1.5.2.1. The detailed site stratigraphic column with descriptions of each geologic unit is provided on Figure 1.5-2. The following discussion, adapted from the Hydrogeologic Evaluation, focuses on those geologic units at or in the vicinity of the site which have or may have groundwater present. The presence of groundwater within and in proximity to the site has been documented in three strata: the Dakota Sandstone, the Burro Canyon formation, and the Entrada/Navajo Sandstone. The Burro Canyon formation hosts perched groundwater over the Brushy Basin Member of the Morrison formation at the site. H 1USERSIWMRCPLN\\SECTO I RPT\\May 1999

Page l-37 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan The Entrada/Navajo Sandstones form one of the most permeable aquifers in the region. This aquifer is separated from the Burro Canyon formation by the Morrison formation and Summerville formation. Water in this aquifer is under artesian pressure and is used by the site's operator for industrial needs and consumption. The artesian conditions present in this aquifer are discussed in Section l.5.6.4. Geologic cross sections which illustrate the stratigraphic position of the Entrada/Navajo Sandstone aquifer and intervening strata are shown on Figures 1.5.3-1, l.5.3-2, and 1.5.3-3 (from Hydrogeologic Evaluation Figures 2.1, 2.2, and 2.3, respectively). The summary of the borehole information supporting the site's stratigraphy, description of the drilling information and boring logs are presented in Appendix A of the Hydrogeologic Evaluation. With the exception of six deep water supply wells installed at various locations around the site and completed in Entrada/Navajo Sandstone, all of the boring data are from wells drilled through the Dakota/Burro Canyon Sandstones and tem1inated in the Brushy Basin Member. The drilling and logging data indicate that the physical characteristics of the bedrock vary considerably, both vertically and laterally. The following sections discuss the relevance of those strata and their physical characteristics to the site's hydrogeology. Dakota Sandstone The Dakota Sandstone is a low-to moderately-permeable formation that produces acceptable quality water at low production rates. Water from this formation is typically used for stock water and/or irrigation. The Dakota Sandstone is the uppermost stratum in which the tailings disposal cells are sited. At the ground surface, the Dakota Sandstone is overlain by a veneer of reddish-brown clayey or sandy silts II IUSERS\\WMRCPLN\\SECTOl ~y 1999

Page l-38 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan with a thickness of up to l O feet and extends to depths of 43 to 66 feet below the surface (D'Appolonia, 1982). The Dakota Sandstone at this site is typically composed of moderately hard to hard sandstones with random discontinuous shale ( claystone) and siltstone layers. The sandstones are moderately cemented (upper part of formation) to well cemented with kaolinitic clays. The claystones and siltstones are typically 2 to 3 feet thick. although boring WMMW-19 encountered a siltstone layer having a thickness of 8 feet at 33 to 41 feet below the ground surface. Porosity of the Dakota Sandstone is predominately intergranular. Laboratory tests performed (see Table 1.5.3.1-1, from Hydrogeologic Evaluation Table 2.1) show the total porosity of the sandstone varies from 13.4 to 26.0 percent with an average value of 19.9 percent. The formation is very dry to dry with volumetric water contents varying from 0.6 to 7.1 percent with an average value of 3.0 percent. Saturation values for the Dakota Sandstone vary from 3.7 to 27.2 percent. The hydraulic conductivity values as determined from packer tests range from 9. l 2E-04 centimeters per second (cm/sec) to 2.71 E-06 cm/sec with a geometric mean of 3.89E-05 cm/sec (Dames & Moore, 1978; Umetco, 1992). A summary of hydraulic properties of the Dakota Sandstone is presented in Table 1.5.3.1-2 (Hydrogeologic Evaluation Table 2.2). H 'USERSIWMJKPLN\\SECTOI lll'l'May 1999

Formation Well No. and Sample Interval Dakota WMMW-16 26.4' - 38.4' WMMW-16 37.8' - 38.4' WMMW-17 27.0' - 27.5' WMMW-17 49.0' - 49.5' Burro Canyon WMMW-16 45.0' - 45.5' WMMW-16 47.5' - 48.0' WMMW-16 53.5' - 54.1' WMMW-16 60.5' - 61.0' WMMW-16 65.5' - 66.0' WMMW-16 73.0' - 73.5' WMMW-16 82.0' - 82.4' WMMW-16 90.0' - 90.7' WMMW-16 91.1'-9).4' WMMW-17 1040' - 1045' Average: Table 1.5.3.1-1 Properties of the Dakota/Burro Canyon Formation White Mesa Uranium Mill Moisture Mosture 01)' Unit Retained Content Content Weight Porosity Particle Saturation Moisture (Percent) Volumetric (lbs/cu ft) (Percent) Sp. Gr. (Percent) (Percent) 1.5 3.3 135.2 17.9 2.64 18.2 5.1 0.4 0.8 127.4 22.4 2.63 3.7 6.3 0.3 0.6 138.8 13.4 2.57 4.8 5.1 3.6 7.1 121.9 26.0 2.64 27.2 9.6 5.6 12.6 140.9 16.4 2.70 77.2 2.6 5.9 142.8 12.0 2.60 48.9 4.4 0.7 1.4 129.0 19.9 2.58 7.1 6.4 0.1 0.2 117.9 27.3 2.61 0.8 9.9 2.6 5.5 131.5 19.3 262 28.2 7.1 0.1 0.3 130.3 20.6 2.63 1.3 5.5 0.1 0.1 134.3 18.5 2.64 0.6 4.8 0.1 0 3 161.5 2.0 2.64 12.8 09 5.2 9.8 118.1 29.1 2.67 33.8 0.2 0.4 161.4 I 7 2.67 26.6 () 8 l.6S 3.4 135 17.6 2.63 21 5.S Adapted from: Table 2. L Hydrogeologic Evaluation. Liquid Plastic Plasticity Limit Limit Index (Percent) (Percent) (Percent) Rock Type Sandstone: Sandstone: Sandstone Sandstone 29.6 15.4 14.2 Sandy Mudstone Sandstone: Sandstone: Sandstone Sandstone Sandstone SandslOne Sandstone 33i 16.2 17.5 ( 'lay stone Sand~tone

Table 1.5.3.1-2 Summary of Hydraulic Properties White Mesa Mill Hydraulic Hydraulic Boring/Well Interval Document Conductivity Conductivity Location Test Type (ft. - ft.) Referenced (ft./yr.) (cm.lsec.) Soils 6 Laboratory Test 9 D&M l.2E+OI I.2E-05 7 Laboratory Test 4.5 D&M I.OE -t-0 I I.OE-05 10 Laboratory Test 4 D&M l.2E+Ol I.2E-05 12 Laboratory Test 9 D&M I.4E +-02 l.4E-04 16 Laboratory Test 4.5 D&M 2.2E+OI

2. I E-05 17 Laboratory Test 4.5 D&M 9.3E+Ol 9.0E-05 19 Laboratory Test 4

D&M 7.0E+Ol 6.8E-05 22 Lahoratory Test 4 D&M 3.9E+OO 3.8E-06 Geometric 2.45E-t01 2.37E-05 Mean Dakota Sandstone No. 3 Injection Test 28-33 D&M (I) 5.68E+02 5.49E-04 No. 3 Injection Test 33-42.5 D&M 2.80E+OO 2.7IE-06 No. 12 Injection Test 16-22.5 D&M 5.IOE+OO 4.93E-06 No. 12 Injection Test 22.5-37.5 D&M 7.92E+OI 7.66E-05 No. 19 Injection Test 26-37.5 D&M 7.00E+OO 6.77E-06 No. 19 Injection Test 37.5-52.5 D&M 9.44E+02

9. 12E*-04 Geometric 4.03E+OI 3.89E-05 Mean Burro Canyon Fonnation No. 3 Injection Test 42.5-52.5 D&M 5.80E+OO 5.61 E-06 No. 3 Injection Test 52.5-63 D&M 1.62E+Ol l.57E-05 No. 3 Injection Test 63-72.5 D&M 5.30E+OO 5.13E-06 No. 3 Injection Test 72.5-92.5 D&M 3.20[+00 3.09E-06

Table 1.5.3.1-2 Summary of Hydraulic Properties White Mesa Mill (continued) Hydraulic Hydraulic Boring/Well Interval Document Conductivity Conductivity Location Test Type (ft. - ft.) Referenced (ft./yr.) (cm.lsec.) No. 3 Injection Test 92.5-107.5 D&M 4.90E+OO 4.74E-06 No. 3 Injection Test 122.5-142 D&M 6.00E+-01 5.80E-07 No. 9 Injection Test 27.5-42.5 D&M 2.70E+OO 2.61 E-06 No. 9 Injection Test 42.5-59 D&M 2.00E+OO l.93E-06 No. 9 Injection Test 59-82.5 D&M 7.00E+OI 6.77E-07 No. 9 Injection Test 82.5-107.5 D&M I. I OE-t-00 I.06E-06 No. 9 Injection Test 107.5-132 D&M 3.00E+OI 2.90E-07 No. 12 Injection Test 37.5-57.5 D&M 9.0IE+OI 8.70E-07 No. 12 Injection Test 57.5-82.5 D&M I.40E+OO I.35E-06 No. 12 Injection Test 82.5-102.5 D&M I.07E+OI I.03E-05 No. 28 Injection Test 76-87.5 D&M 4.30E+OO 4.16E-06 No. 28 Injection Test 87.5-107.5 D&M 3.00E+OI 2.90E-07 No. 28 Injection Test 107.5-132.5 D&M 2.00E+OI l.93E-07 WMMWI (7) Recovery 92-112 Peel (2) 3.00E+OO 2.90E-06 WMMW3 (7) Recovery 67-87 Peel 2.97E+OO 2.87E-06 WMMWS (7) Recovery 95.5-133.5 H-E IJIE+OI I.27E-05 WMMW5 (7) Recovery 95.5-133.5 Peel 2.IOE+OI 2.03E-05 WMMWll (7) Recovery 90.7-130.4 H-E (3) I.23E+03 I.19E-03 WMMWll (7) Single well drawdown 90.7-130.4 Peel l.63E+03 l.58E-03 WMMW12 (7) Recovery 84-124 H-E 6.84E+Ol 6.61E-05 WMMW12 (7) Recovery 84-124 P~el 6.84E+Ol 6.61E-05 WMMW14 Single well drawdown 90-120 (5) H-E l.21E+03 l.16E-03 WMMW14 Single well drawdown 90-120 (6) H-E 4.02E-t02 3.88E-04 WMMW15 Single well drawdown 99-129 H-E 3.65E+Ol 3.53E-OS WMMW15 (7) Recovery 99-129 Peel 2.58E+Ol 2.49E-OS WMMW16 Injection Test 28.5-31.5 Peel 9.42E+02

9. lOE-04 WMMWl6 Injection Test 45.5-51.5 Peel 5.28E+Ol 5.IOE-05

Table 1.5.3.1-2 Summary of Hydraulic Properties White Mesa Mill (continued) ..... ~ Hydraulic Hydrauik Boring/Well Interval Document Conducti\\*ity 'Conductivity Location Test Type (ft. - ft.) Referenced (ft.lyr.) (cm./sec.) WMMWl6 Injection Test 65.5-71.5 Peel 8.07E+O I 7.80E-05 WMMWl6 lnj,.ction Test 85.5-91.5 Peel JOOE+OI 2.90[-05 WMMWl7 Injection Test 45-50 Peel

3. IOE *00 3.00f:-06 WMMWl7 Injection Test 90-95 Peel J.62E+OO 3.SOE-06 WMMWl7 Injection Test 100-105 Peel 5.69E+OO 5.50E.06 WMMWl8 Injei.:tion Test 27-32 Peel l.14E+02 I. IOE-04 WMMWl8 lnjer.tion Test 85-90 Peel 2.69E+OI 2.60E-05 WMMW18 Injection i*est 120-125 Peel 4.66E+OO 4.SOE-06 WMMWl9 lnjection T*~st 55-60 Peel 8.69E-00 8.40[-06 WMMWl9 Injection Test 95.. 100 Peel l.45E+OO I.411E-06 Geometric l.05E+Ol 1.0lE-05 Mean Entracia1Navajo Sandstones WW-I Recovery D Appolonia (4) 3.80E +02 3.67E-04 WW-I Multi-well drawdo.vn D'Appolonia 4.66E1-02 4.SOE-04 WW-1.2,3 l\\lulti-well drawdown D'Appolonia 4.24E+02 4.101:-04 Geometric 4.22E+02 4.08E-04 Mean D&M"' Dames & Moore, Environmental Report. White Mesa Uranium Project, January, 1978.

Notes: (I) (2) (3) (4) (5) (6) (7) Peel"' Peel Environmental Services, lfMETCO Minerals Corp., Ground Water Study, White Mesa Facility, June 1994. H-E= Hydro-Engineering, Ground-Water Hydrology at the White Mesa railings Fac1dy, July, 1991. D'Appolonia, Assessment of the Water Supply System. White Mesa Project, Feb. 1981. Early test data. Late test data. Test data reanalyzed by TEC. Adapted from: Table 2.2, Hydrogeologic Evaluation.

Burro Canyon Sandstone Page 1-43 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan Directly below the Dakota Sandstone, the borings encountered sandstones and random discontinuous shale layers of the Burro Canyon formation to depths of 91 to 141 feet below the site. The importance of this stratum to the site's hydrogeology is that it hosts perched water beneath the site. Beneath the Burro Canyon formation, the Brushy Basin Member is composed of variegated bentonitic mudstone and siltstone; its permeability is lower than the overlying Burro Canyon formation and prevents downward percolation of groundwater (Haynes, et al, 1972). Observed plasticity of claystones (Umetco, 1992) forming the Brushy Ba~in Member indicates low potential for open fractures which could increase permeability. Section 1.5.3.2 contains a summary of a drilling program carried out in response to agency requests to obtain additional hydrogeologic data. Previous investigators have seldom made a distinction between the Dakota and Burro Canyon Sandstones. However, examination of borehole cuttings, cores and geophysical logging methods has allowed separation of the two formations. Although similar to the Dakota. the Burro Canyon formation varies from a very fine-to coarse-grained sandstone. The sand grains are generally poorly sorted. The coarse-grained layers also tend to be conglomeratic. The grains are cemented with both silica and kaolin, but silica-cemented sandstones are dominant. The formation becomes argillaceous near the contact with the Brushy Basin Member. The saturated thickness in the Burro Canyon formation varies across the project area from 55 feet in the northern section to less than 5 feet in the southern area. Some wells are dry, which suggests that the zone of saturation is not continuous. Saturation ceases or is marginal along the western and southern section of the project. The extent toward the east is not defined, but its maximum extent is certainly not beyond the walls of Westwater Creek and Corral Canyons where the Burro Canyon H it!SEJlS,WMRCPLN\\SECTOI RPl'May 1999

Page 1-44 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan formation crops out. Perched groundwater elevations and saturated thickness of this formation are shown on Figures 1.5.3.1-4 and 1.5.3.1-5, respectively (from Hydrogeologic Evaluation Figures 2.4 and 2.5). Hydraulic properties of this stratum have been determined from 12 single, well-pumping/recovery tests and from 30 packer tests. A summary of the hydraulic properties is given in Table 1.5.3.1-2 (Hydrogeologic Evaluation Table 2.2). These tests indicate the hydraulic conductivity geometric mean to be l.OE-05 cm/sec. The physical properties of the Burro Canyon Sandstone are summarized in Table 1.5.3.1-1. Based on the core samples tested, the sandstones of the Burro Canyon fonnation vary in total porosity from 1.7 to 27.6 percent, the average being 16.0 percent. Volumetric water content in these sandstones ranges from 0.1 to 7.1 percent, averaging 2.2 percent, with the fine-grained materials having the higher moisture content. Porosities in the claystone layers vary from 16.4 to 29.1 percent with saturation values ranging from 33.8 to 77.2 percent. II IUSERS\\WMRCJ't.NISECTOI JU>T\\May 1999

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Brushy Basin Member Page 1-46 Revision.2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan The Brushy Basin Member of the Morrison fonnation is the first aquitard isolating perched water in the Burro Canyon fonnation from the productive Entrada/Navajo Sandstones. The Brushy Basin Member, in contrast to the overlying Dakota Sandstone, is composed of bentonitic mudstone and claystonc. Limited site-specific hydraulic property data are available for the Brushy Basin Member. The thickness of the Brushy Basin Member in this region reportedly varies from 200-450 feet (Dames & Moore, 1978). This stratum was penetrated by six water supply wells [see Figure 1.5.3.1-1 (Hydrogeologic Evaluation Figure 2.1 )]and Appendix A of the Hydrogeologic Evaluation) and its thickness was estimated at 275 feet. Borings which tenninate in the Brushy Basin Member encounter moderately plastic dark green to dark reddish-brown mudstones. Plastic bentonitic mudstone is not prone to develop fracturing. Hence, competency of this strata, as an aquitard, is very likely. Entrada/Navajo Aquifer Within and in proximity to the site, the Entrada/Navajo Sandstones are both prolific aquifers. Since site water wells are screened in both aquifers, they are, from a hydrogeologic standpoint, treated as a single aquifer. The Entrada/Navajo Sandstone is the first useable aquifer of significance documented within the project area. lbis aquifer is present at depths between 1,200 and 1,800 feet below the surface and is capable of delivering from 150 to 225 gpm of water per well (D' Appolonia, 1981). H IUSEJ.S\\WMllCPLN\\SECTOI RP'I\\May 1999

Page 1-47 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan Water is present under artesian pressure and is documented to rise by about 800 to 900 feet above the top of Entrada/Navajo Sandstone contact with the overlying Summerville formation. The static water level is about 400 to 500 feet below the surface (Figures 1.5.3.1-2 and l.5.3.1-3). Section 1.5.6.4. provides a more detailed discussion regarding the artesian conditions of this formation. The thickness of the strata separating this aquifer from water present in the Burro Canyon fomiation is about 1,200 feet. This confining layer is competent enough to maintain pressure of 900 feet of water or 390 pounds per square inch (psi) within the Entrada/Navajo Aquifer. The positioning of this aquifer and its hydraulic head versus other strata is shown on Figures 1.5.3.1-2 and 1.5.3.1-3. In-situ hydraulic pressure of groundwater in the Entrada/Navajo Aquifer is strong evidence of the confining (i.e. "aquitard") properties of the overlying sedimentary section. Due to the presence of significant artesian pressure in this aquifer, any future hydraulic communication between perched water in the Burro Canyon formation and the Entrada/Navajo Aquifer is unlikely. 1.5.3.2 Data Collected in 1994 This subsection contains a summary of a 1994 drilling program carried out in response to a request by the U.S. Nuclear Regulatory Commission (NRC) and the U.S. Environmental Protection Agency (EPA) to further investigate the competence of the Brushy Basin member of the Morrison formation and to provide additional hydrogeologic data. Three vertical and four angle core holes were drilled. fl \\USEllSIWMII.CPLN\\SECTOI RP'J\\M,.y 1999

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Page 1-50 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan The three vertical holes (WMMW-20, WMMW-21. and WMM\\V-22) were drilled downgradient of the existing monitoring wells. Constant head packer tests were conducted over intervals within the Brushy Basin member to gain information about the horizontal hydraulic conductivity of this unit. Selected cores samples of the Brushy Basin member were analyzed for vertical hydraulic conductivities. The three vertical holes were drilled to sutlicient depth to penetrate 2(}+/-: feet of Brushy Basin Member. Four core holes were drilled along the edge of tailings ponds No. 3 and No.

4. The cores were examined to determine if open fractures were present. Few fractures were observed, and where noted, they were closed and infilled with gypsum. Packer tests were conducted during the drilling of the holes to gain further information about the hydraulic conductivity of the rocks.

Upon completion of drilling, all the geotechnical holes were logged using wireline geophysical methods. A video camera survey was performed in three of the four core holes. The holes v,ere then plugged and abandoned. Selected cores of the Brushy Basin from all the holes were sent for laboratory measurement of the vertical permeability. The results of these tests are presented in Table l.5.J.2-1. The hydraulic conductivities calculated from these tests vary from 7.1 OE-06 cm/sec to 8.90E-04 cm/sec in the Dakota formation, from 9.88E-07 cm/sec to 7.70E-04 cm/sec in the Burro Canyon formation and from 2.JOE-07 cm/sec to l.91£-06 cm/sec in the Brushy Basin member. Three packer tests run within the Brushy Basin member yielded "No Talce." Due to the low hydraulic conductivities. measurements could not be made with the equipment available. The hydraulic conductivities of these zones can be expected to be lower than the zones in which actual measurements were made. It can, therefore, be a.<<,sumed that the hydraulic conductivities of these zones are less than 2.JOE-07 H \\USEJlSIWMJlCPlN\\SECTOI RP1'May 1999

Page 1-51 Revision 2.0 International Uranium ( USA) Corp. White Mesa Mill Reclamation Plan cm/sec. Packer tests tend to reflect horizontal hydraulic conductivities which can be expected to be greater than vertical hydraulic conductivities of the same zone. Slug tests were conducted in wells WMMW-20 and WMMW-*22. The test results are :.;hown in Table 1.5.3.2-1. A hydraulic conductivity of 3.14E-06 cm/sec was calculated for WMMw.... zo and 9.88E-07 cm/sec (essentially l.OE-06 cm/sec) for WMMW-22. Cores from the Brushy Basin were sent to Western Engineers of Grand Junction, ('olorado for horizontal and vertical permeability determination. The results of these tests are shown on lahlc l.5.3.2-2. The vertical hydraulic conductivities of the cores vary from 5.95E-04 to 7.28E* 1 l cm/sec The geometric mean of the vertical permeabilitie~ is l.23E-08 cm/sec. For the few analyses conducted for horizontal permeabilities. the results ranged from I 09F--07 to 6.14E 4 10 cm/sec and the geometric mean of these values was calculated to be 6.72E-09 cm/sec. Packer tests were conducted over zones within the Dakota. Burro Canyon and Brushy Basin units. The cores and video surveys of the drill holes showed that the few closed hairline fractures present in the Burro Canyon and Dakota Formations do not substantially atlect the hydraulic conductivity of the fomiations. H lllSl'Jt\\llWMllfPl.N\\SECTOI i\\Yl'.Mav 1999

Well No WMMW-20 WMMW-21 WMMW-U GH-94-1 <iH-94-.~A GH-94-3 TABLE 1.5 J.2.. 1 Summary of Borehole rests, 1994 Drilling Program White Mesa Project. San Juan County. l ltah Interval 110 5-114.5 87 0-90 0 I 09 5-117 0 l l0.0-140.0 J6.. 1:w l4.0-40.0 ,.l()(kiO () 70.0--80 0 92 0-1 (}(J IOJ0-110.0 110.0-140.0 16J 0-165.0 H0-40 0 l2.5AO.O 50 0*56 0 60.0-70.0 70.0**80 0 80.0~90.0 I 38.0-144 0 155 0-1610 138.0- 144.0 lype of rest Constant Head Slug Constant Head

l. onstant Head Slug Constant Head Constant Head Constant Head Constant Head Constant Head Constant Head Constant Head Constant Head Constant Head Constant Head

( *omtant Head Constant Head Constant Head Constant Head Constant Head Constant Head Formation Brush} Basin Burro Canyon Brushy Basin Brushy Basin Burro Canyon Dakota Dakota Burro Canyon Burro Can\\,on Burro Cany@ Brush} Basin Brushy Basin Dakota Dakota Oakota Burro Canyon Burro Canyon Burro C'auyon Brushy Basm Brnshy Basin Brushy Basin Hydraulr1: Hydraulil Conductivity Conduct iv it} MW1'n *2 cmisei: 0 005 .i l()J... ()7 0015 ~.!9L-011 0 I 7 No lake 0.06 0 16 I 18 t} 0 I I; I l.'i 84 \\ ti 0.66 18 72

1. JO 1()4 4.18 302 0.07 0.06 l I4F-06

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9. 88f-. -0 7 6.!OL-04 7 7()f.()4 I 701* -04 No I ake l l lH*.()'i 8 901:-!M l I Of-. o.i 4.90F-(l"i 2 OOE-04 I 50E-04

-No Take-U6E-06 2 70fAJ6

Well !\\Ju. tet WMMW-20 WMMW i, (ill-I < ill -~A < ill I Well No. WMMW-20 WMMW-21 L\\BU: I 5.J.2-: Results ot J.aboratorv I csts Interval lestcd Lit) ~ 95,l 96.0 1040-104 t l(l'i 0-lO~ 'i 1oq i 110.0 I O<d. I O 7 il i l *l 'i 11.'i 0 122 1 I.'.2 7 126 1 '2?:'. l lJ. 1. 111 117 l I ! 7 8 l(d0-163 ~ 165 0 16'1 'i lhl (). 161 ';; 1 *~7 0 I :'i7. "i I 58 0-1 '\\8, Interval lested lftJ 954-96.0 1050-105 5 94 8-95 l ll7\\IJ78 I urmat 1011 I ested Brush)-' Basm Brushy Basrn Hrushy Aas111 Hru,;hy Basm Brus In Has Ill Brush, Basm Brushy Bastn Brush} Basm Brushy Basm Brush" Basm Brushy Basm rlrush:,, Basin Brushy Basm Brushy Basin Brushy 1:Jasm Brushv Basin Brushy Basin Formation rested 7 Brush, Ba~iin Brushy Basin Brushy Basin Brushy Basin

== V<:rt1rnl Ptrmcahilitie~ Un St!I: 1 1/()1* I I .' %1-0()

• '.'Ml Ii

~ 7Mf (/(l ti 31H 10 I -to! -0 ' I 081 06 6 *MI* 10 ) 111-01.i ~ l)'i f O,t I 68f 08 (\\ !61 (P .. '. I 71* -09 Ml 1 luruonal P~mio..:ab1 l 11 ie~ I 091---07 6 l 41* I 0 8 111 -10 .1 67F--08

Page 1-54 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan The climate nf southeastern Utah is classified as dry to arid continental. The region is generally typified by warm summer and cold winter temperatures, with precipitation averaging less than 11.8 inches annually and evapotranspiration in the range of 61.S inches annually (Dames and Moore, 1978 ). Precipitation in southeastern Utah is characterized by wide variations in seasonal and annual rainfall and by long periods ofno rainfall. Short duration summer stom1.s furnish rain in small areas of a few square miles and this is frequently the total rainfall for an entire month within a given area, The average annual precipitation in the region ranges from less than 8 inches at Bluff to more than 16 inches on the eastern flank of the Abajo ~fountains, as recorded at Monticello. The mountain peaks in the Henry, La Sal and Abajo Mountains may receive more than 30 inches of precipitation. but these areas are very small in comparison to the vast area of much lower precipitation in the region. T'he perched water in the Burro Canyon formation originates in the areas north of the s:te as shown by the direction of groundwater tlow from north to south (see Figure l.S.S.. t), The thickness of saturation is greatest in the northern and central sections of the site and reduces toward the south. The configuration of the perched water table and map of saturated thicknesses are provided on Figures I.5,5-1 and 1.5.5-2. respectively. The topography of the Brushy Basin Member which defines the bottom of the perched water is shown on Figure 1.5.5-3 (Hydrogeologic Evaluation Figure 2.6). H *.lJS81S\\W~CPLN\\Slifl'OI kP1\\Mav 1'199

i'.11,,te I i ; ~t. j**,f\\111 l i I lmenHUHillttl I r,mrnm, I \\ *\\ 11 orp Whitt: l\\1e"a Mill Rt~\\. lttrn<:tl.lon Pl,111 lhe groundwakr trum ttw Hmru <,un on formation d1,,1.."h11rf!tt~s mto tht* adp:u..i*nt tam 1 *n, t \\\\ c,t\\\\ati,*1 Creek. and t *orrnl l *amorn as evHkrh:~d hy iJ'l1*in~s and prndtKl.nt: ""~f!lt~t,.tt111n patlt~m,, "'i,in11: pmt ot the grounth.Hth:'1 fin'>\\. mav ent,*r thi: l\\rush, H;:1.srn 1\\tfcmht.'t 'HI relwt ltad1m**,,1.h1th,,~, 111,n clo'it' proxHlllt\\ to the canyons I ht~ l11nH1on nt ttw 1:,U1\\.1>ib whH h hound tht \\,\\ hnc \\*h*s.i 1lf1 1111* west east,utd 'iouth art" shO\\-vn on h~ure I " { I lhe gcometrit mean of the hvdrnuhl condul'111,.11, ol Hu:,;aturnted pan Pl Burro<,un1Ht 1t1tn1tH1,1n ts I 01 -ih cm/set: I h.t l.\\<ater v1~ld per \\'¥t~ll 1s 1.cry lov.. a,;,; dou.mietlf.t!d h\\ mni, p1u11111nt,1 h'"'h and is tvp1ndly belov. 0 *" MPHI In l'.Onlra!it to tht: vcn Im\\ pumpm~ rntt:s 11hst'.fv1;:d rn,;*1~h1 i,elh. V.. di WMMW

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Table J.5.,-1 Monitorin1 Well and Ground Water Elevation Data White Mesa Uranium Mill Water Level Measuring Point *- Well Name Date Total Perforations Depth Elevation Above Elevation lnstaHed Depth Date (ft.) (ft.-MSL) LOS (ft.) (ft.-MSL) WMMW I Sep* 79 117' 92'-112' 11 1 19/92 75.45 5572.77 2.0

5648 22 WMMW-2 Sep-79 128.8' 85'-125' 11

• 19!92 110.06 5503.4) 18 56 IJ.49 WMMW***1 Sep-79 98' 6 7'-87' II 19192 83 74 5471 58 2.0 5.'i55 32 WMMW-4 Sep-79 1:236' 92' 12' II 19:92 92.42 5530.15 16 5622 57 WMMW:5 May-80 I 36' 95S-JJJS 11 19/92 108.32 0.6 5609.33 WMMW-6 May-80 rhis well was destroyed during <.:onstmction of Cell 3.

WMMW-7 May-80 fnis well was destroyed during construction of Cell 3. WMMW-8 May-80 fhis well was destroyed during construction of Cell 3. WMMW.. JI Oct-82 I 35'

90. 7'

• I J0.4' 11 19192 I 02.53 5508.55 2.4 5611.08 WMMW-12 Oct-82 I.30J' 84'-124' I l 1 l9i92 109.68 5499 77

() 9 5609.45 WMMW-13 Oct-8:2 I 185' T'his well was destroyed during 1..:onstruction of Cell 4A. WMMW,14 Sep-89 129 I' 90'-120' l I '19i92 105.34 5491.05 0.0 5596.39 WMMW.. 15 Sep-89 138' 99'-129' lfil9*92 108.28 5490.34 0.8 5598.62 WMMWl6 Dec-92 915' 78.5'-88 5' 7'12192 Dry 1.5 WMMW-17 Dec-92 110' 90'-100' 11 *30/92 87.56 1.5 WMMW*l8 Dec-92 148.5' IOJ5'-IB5' 11130/92 92.11 1.5 WMMW-19 Dec-92 149' IOl'-131' 10/12192 85.00 I 5

1. 9-l May-80 ns I0'-30' 1.14,91 Dry 1.8 5622.83
2. 9-2 May-80

62. 7' J9.7"-59.7" J,4/91 Dry 5622.58

1. I0-2 May-80 LU' I IJ'-313' J,4/91 Dry 2

5633.58

1. 10*2 May-80 62 2' 39.2'-59.2' J/4/91 Dry 2.1 5633.39 Notes:

I. Well locations provided on Figure 1.5.3-l.

2.

LDS "" leak detection system. .. 3. tl-MSL *"' feet

• mean sea level.

Adapted from: Table 2.3, Hydrogeologic Evaluation

I.5S I Perched Water Quality Page 1-60 Revision 2.0 International Uranium ( USA) Corp. White Mesa Mill Reclamation Plan Groundwater monitoring of the Burro Canyon formation saturated zone has been conducted at the \\\\bite Mesa facility since 1979. Table 1.5.5-1 (Hydrogeologic Evaluation Table 2.3) provides a list of wells that have been constructed for monitoring purposes at the facility. Figure 1.5.3. l-1 indicates the locations of these wells. The water quality data obtained from these wells are provided both in tabular and graphical fonn in Appendix B of the Hydrogeologic Evaluation, with more recent data in the Semi-annual Effluent Report for July throuah December 1995 and the Semi~annual Effluen! Regort fgr JanuQ.ry throuah June 1995 (Energy Fuels Nuclear, Inc). Examination of the spatial distribution and temporal trends (or lack thereof) in concentrations of analyzed constituents provides three significant conclusions: I. The quality of perched water throughout the site shows no discernible pattern in variation,

2.

The water is generaJly of poor quality [ moderately high values of chloride, sulfate, and totally dissolved solids (TDS)I, and

3.

Analytical results show that operations at the White Mesa Uranium Mill have not impacted the quality of the perched water of the Burro Canyon formation. To arrive a these conclusions, comparisons of the water chemistries from the various wells were analyzed in the Hydrogeologic Evaluation by graphical techniques. The purpose of the comparisons was to determine if trends in chloride, which would be associated with water from the tailings ponds,

Page l-6 l Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan were increasing in the perched water of the Burro Canyon formation. The trilinear plot and the Stiff diagram were used to conduct a preliminary evaluation of differences or similarities in water quality data between wells. The following is a summary of the conclusions drawn in the Hydrogeologic Evaluation. Temporal and Spatial Variations The trilinear plots and Stiff diagrams presented in the Hydro geologic Evaluation (Figures 2. 7-2.10) show that the water from all wells is of the sulfate (anion) type. The cation definition of the water type is variable. Of the 13 wells analyzed for water chemistry, four fall in the calcium-sulfate type category, four faJl in the (sodium plus potassitun)-sulfate type, two samples classify as the magnesium-sulfate type. Five samples have no dominant cation type. However, these five samples tend to classify more closely to the (sodium plus potassium)-sulfate and calcium-sulfate types. The spatial variability of water quality data within the Burro Canyon formation is illustrated on Hydrogeologic Evaluation Figures 2. 7 through 2.13, and the data Tabled in Appendix B of the Hydrogeologic Evaluation. UpgradientMonitoring Wells WMMW-1, WMMW-18,and WMMW-19 varied in sulfate concentrations from 676 to 1736 milligrams per liter (mg/1). Likewise, chloride concentrations in these wells varied from 12 to 92 mg/I. Across the site, sulfate and chloride concentrations vary with no discernible pattern to the variations. Details regarding chemistry of the Burro Canyon formation water can be found in Appendix B of the Hydrogeologic Evaluation. Variability of water within the Burro Canyon formation is the result of slow moving to nearly stagnant groundwater flow beneath the site. These conditions are likely leading to dissolution of minerals from the Brushy Basin Member and the formation of sulfate-dominated waters. H 1USERSIWMJ\\CPLN\\SECTOI RPTIM1y 1999

Statistical Analysis Page l-61 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclarr:3tion Plan Because of the variable groundwater chemistry in the Burro Canyon formation baseline data, comparison of individual well growidwater chemistries to a single background groundwater well is not an appropriate method of monitoring potential disposal cell leakage or groundwater impacts. Water quality baseline and comparisons to that baseline established on a well-by-well basis has been proposed in the POC, as this method will best provide a meaningful representation of changes in groundwater chemistry. Based on a review of water quality data gathered from 1979 through 1992, which are presented in the Hydrogeologic Evaluation, and considering the apparent variability of chemical composition of perched water and the absence of any impact from operations, EFN proposes to apply, an intra-well approach for assessing water quality trends. This approach, described in Appendix C, the Points of Compliance (POC) report (Titan, 1994), involves determination of background concentrations for a number of selected wells. 1.6 GEOLOGY The following text is copied, with minor revisions, from the Environmental Report (Dames and Moore, 1978b) (ER). The text has been duplicated herein for ease of reference and to provide background information concerning the site geology. ER Subsections used in the following text are shown in parentheses immediately following the subsection titles. The site is near the western margin of the Blanding Basin in southeastern Utah and within the Monticello uranium-mining district. Thousands of feet of multi-colored marine and non-mru.ine HIUSERS\\WMRCPLNISECTOIRPT\\Mayl999

Page 1-63 Revision 2.0 International Uranium (USA) Corp. \\\\'hite Mesa Mill Reclamation Plan sedimentary rocks have been uplifted and warped, and subsequent erosion has carved a spectacular landscape for which the region is famous. Another unique feature of the region is the wide-spread presence of unusually large accumulations of uranium-bearing minerals. 1.6. l Regional Geology The following descriptions of regional physiography; rock units; and structure and tectonics are reproduced from the ER for ease of reference and as a review of regional geology. 1.6.1.1 Physiography (ER Section 2.4.1. l) The project site is within the Canyon Lands section of the Colorado Plateau physiographic province. To the north, this section is distinctly bounded by the Book Cliffs and Grand Mesa of the Uinta Basin~ western margins are defined by the tectonically controlled High Plateaus section, and the southern boundary is arbitrarily defined along the San Juan River. The eastern boundary is less distinct where the elevated surface of the Canyon Lands section merges with the Southern Rocky Mountain province. Canyon Lands has undergone epeirogenic uplift and subsequent major erosion has produced the region's characteristic angular topography reflected by high plateaus, mesas, buttes, structural benches, and deep canyons incised into flat-laying sedimentary rocks of pre-Tertiary age. Elevations range from approximately 3,000 feet (914 meters) in the bottom of the deeper canyons along the southwestern margins of the section to more than 11,000 feet (3,353 meters) in the topographically anomaloas laccolithic Henry, Abajo and La Sal Mountains to the northeast. Except for the deeper H IUSEJlS\\WMJ.CPLN\\SECTOI Rl'l\\May 1999

Page 1-64 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan canyons and isolated mountain peaks, an average elevation in excess of 500 feet (1,524 meters) persists over most of the Canyon Lands section. On a more localized regional basis, the project site is located near the western edge of the Blanding Basin, sometimes referred to as the Great Sage Plain (Eardly, 1958), lying east of the north-south trending Monument Uplift, south of the Abaja Mountains and adjacent to the northwesterly-trending Paradox Fold and Fault Belt (Figure 1.6-1). Topographically, the Abaja Mountains are the most prominent feature in the region, rising more than 4,000 feet (1,219 meters) above the broad, gently rolling surface of the Great Sage Plain. The Great Sage Plain is a structural slope, capped by the resistant Burro Canyon formation and the Dakota Sandstone, almost horizontal in an east-west direction but descends to the south with a regional slope of about 2,000 feet (610 meters) over a distance of nearly 50 miles (80 kilometers). Though not as deeply or intricately dissected as other parts of the Canyon Lands, the plain is cut by numerous narrow and vertical-walled south-trending valleys 100 to more than 500 feet (30 to 152+ meters) deep. Water from the intermittent streams that drain the plain flow southward to the San Juan River, eventually joining the Colorado River and exiting the Canyon Lands section through the Grand Canyon. 1.6. l.2 Rock Units (ER Section 2.4. l. l) The sedimentary rocks exposed in southeastern Utah have an aggregate thickness of about 6,000 to 7,000 feet (1,829 to 2,134 meters) and range in age from Pennsylvanian to Late Cretaceous. Older unexposed rocks are known mainly from oil well drilling in the Blanding Basin and Monument Uplift. These wells have encountered correlative Cambrian to Permian rock units of markedly II \\USEASIWMJ\\CPLNISECTOI IU'l\\May 1999

Page 1-65 Revision 2.0 International Uranium (USA) Corp. White Mesa Mill Reclamation Plan differing thicknesses but averaging over 5,000 feet (1,524 meters) in total thickness (Witkind, I 964 ). Most of the wells drilled in the region have bottomed in the Pennsylvanian Paradox Member of the Hennosa fonnation. A generalized stratigraphic section of rock units ranging in age from Cambrian through Jurassic and Triassic (?), as determined from oil-well logs, is shown in Table 1.6-1. Descriptions of the younger rocks, Jurassic through Cretaceous, are based on field mapping by various investigators and are shown in Table I.6-2. Paleozoic rocks of Cambrian, Devonian and Mississippian ages are not exposed in the southeastern Utah region. Most of the geologic knowledge regarding these rocks was learned from the deeper oil wells drilled in the region, and from exposures in the Grand Canyon to the southwest and in the Uinta and Wasatch Mountains to the north. A few patches of Devonian rocks are exposed in the San Juan Mountains in southwestern Colorado. These Paleozoic rocks are the result of periodic transgressions and regressions of epicontinental seas and their lithologies reflect a variety of depositional environments. In general, the coarse-grained feldspathic rocks overlying the Precambrian basement rocks grade upward into shales, limestones and dolomites that dominate the upper part of the Cambrian. Devonian and Mississippian dolomites, limestones and interbedded shales unconfonnably overlay the Cambrian strata. The complete absence of Ordovician and Silurian rocks in the Grand Canyon, Uinta Mountains, southwest Utah region and adjacent portions of Colorado, New Mexico and Arizona indicate that the region was probably epeirogenically positive during these times. The oldest stratigraphic unit that crops out in the region is the Hennos formation of Middle and Late Pennsylvanian age. Only the uppermost strata ofthis formation are exposed, the best exposure being in the canyon of the San Juan River at the "Goosenecks" where the river traverses the crest of the H IUSERSIWMllCPLN\\SECTOI RPT\\May 1999}}