Text

Rev 1 to Final SRP for Review & Remedial Action of Inactive Mill Tailings Sites Under Title I of Umtrca
	ML20134B841
Person / Time
Issue date:	06/22/1996
From:	; NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS)
To:	;
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ML20134B840	List: ML20134B838; ML20134B841;
References
	REF-WM-5 PROC-960622, NUDOCS 9608140156
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i FINAL STANDARD REVIEW PLAN for the Review and Remedial Action of inactive Mill Tailings Sites under Title I of the Uranium Mill Tailings Radiation Control Act Revision 1 U.S. Nuclear Regulatory Commission Office of Nuclear Material Safety and Safeguards Division of Low-Level Waste Management and Decommissioning June 1993 seR*20 nie " "

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REVISION CONTROL SHEET CHAPTER /SECTION REVISION PAGES EFFECTIVE DATE introduction 1.0 Chapter 1.0 1.0 Chapter 2.0 1.0 Chapter 3.0 1.0 Chapter 4.0 1.0 Chapter 5.0 1.0 Appendix A 1.0 Appendix B 1.0 Appendix C 1.0 Appendix D 1.0 Appendix E 1.0 I

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1 TABLE OF CONTENT I NTR O D UCTI ON..................................................

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i 1.0 G EO LOG Y AN D SEIS MO LO G Y....................................

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1.1 Areas of Review...........................................

1.1.1 Geologic and Seismologic Characterization.....................

7 1.1. 2 Ge ologic Sta bilit y.......................................

7 1.1.3 Bedrock Suitability......................................

7 1.1.4 Geomorphic Sta bility.....................................

7 1.1.5 Seismotectonic Sta bility..................................

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1. 2 A cceptance Criteria.........................................

8 1.2.1 Regulatory Requirements..................................

8 1.2.2 Regulatory Guidance.....................................

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1. 3 R e vie w Proced ure s..........................................

9 1.3.1 Geologic and Seismologic Characterization.....................

9 1.3. 2 Ge ologic Sta bility.......................................

9 10 1.3.3 Bedrock Stability 1.3.4 Geom orphic Sta bility..................................

11 1.3.5 Seismotectonic Stability.................................

12 1.4 Evaluation Findings...............

13 1.5 References 14 2.0 GEOTECHNICAL STA BILITY.....................................

15 2.1 Areas of Review 15 2.1.1 Characterization of Site Stratigraphy and Uranium Mill Tailings 15 2.1. 2 Slo pe S ta bility........................................

15 2.1. 3 Se ttle me nt...........................................

15 2.1.4 Liquefaction Potential 15 2.1.5 Soil Cover Engineering Parameters..........................

15 2.1.6 Construction Considerations..............................

16 2.1.7 Radon / Infiltration Barrier Hydraulic Conductivity.................

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2. 2 Acce pta nc e Criteria........................................

16 2.2.1 Regulatory Requirements...........

16 2.2.2 Regulatory Guidance....................................

17 2.3 Revie w Procedures.........................................

17 2.3.1 Characterization of Site Stratigraphy and Uranium Mill Tailings......

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2. 3. 2 Slope Sta bility........................................

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2. 3 3 Se ttlement...........................................

21 21 2.3.4 Liquefaction Potential 2.3.5 Soil Cover Engineering Parameters..........................

22 2.3.6 Construction Considerations 22 23 2.3.7 Hydraulic Conductivity 2.4 Evaluation Finding s.........................................

24 2. 5 R e f e r e nc e s..............................................

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__.___m 27 3.0 SURFACE WATER HYDROLOGY AND EROSION PROTECTION.............

27 3.1 Areas of Review..........................................

27 3.1.1 Hydrologic Description of Site.............................

27 3.1.2 Flooding Determinations.................................

3.1.3 Water Surface Profiles, Channel Velocities, and Shear Stresses......

28 28 3.1.4 Erosion Protection Design................................

3.1.5 Design of Unprotected Soil Covers and Vegetated Soil Covers.......

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29 3.2 Acceptance Criteria........................................

29 3.2.1 Regulatory Requirements.................................

29 3.2.2 Regulatory Guidance....................................

30 3.3 Review Procedures.........................................

30 3.3.1 Hydrologic Description of Site.............................

30 3.3.2 Flooding Determinations.................................

3.3.3 Water Surface Profiles, Channel Ve% cities, and Shear Stresses......

33 33 3.3.4 Erosion Protection Design................................

33 3.3.4.1 Top Slope......................................

33 3.3. 4. 2 Side Slope......................................

33 3.3.4.3 A pr on/ Toe......................................

3.3.4.4 Diversion Channels................................

34 3.3.4.5 R ock Durability...................................

35 3.3.4.6 Construction Considerations..........................

35 3.3.5 Design of Unprotected Soil Covers and Vegetated Soil Covers.......

35 35 3.4 Evalua tion Finding s.........................................

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3. 5 Re f er e nce s..............................................

4.0 WATER RESOURCES PROTECTION................................

39 39 4.1 Areas of Review..........................................

4.1.1 Site Chaectorization....................................

39 39 4.1.2 Conceptual Design.....................................

40 4.1.3 Disposal Standards.....................................

40 4.1.4 Ground-Water Cleanup..................................

40 4.1.5 Supplemental Standards.................................

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4. 2 Acceptance Criteria........................................

40 4.2.1 Regulatory Requirements.................................

43 4.2.2 Regulatory Guidance....................................

43 4.3 Review Procedures.........................................

4.3.1 Site Characterization....................................

43 43 4.3.1.1 Facility Characterization.............................

44 4.3.1.2 Vicinity Characterization 44 4.3.1.3 Hydrogeologic Characterization 4.3.1.3.1 Identificatien of Hydrogeologic Units............

45 4.3.1.3.2 Hydraulic and Transport Properties.............

46 4.3.1.3.3 Geochemical Conditions and Contamination Extent..

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4.3.1.3.4 Water Use..............................

50 51 4.3.2 Conceptual Design Features 54 4.3.3 Disposal Standards.....................................

4.3.3.1 Ground-Water Protection Standards 54 4.3.3.1.1 Hazardous Constituents......

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GW" 4.3.3.1.2 Concentration Limits.......................

58 4.3.3.1.3 Point of Compliance.......................

59 4.3.3.2 Performance Assessment............................

59 4.3.3.3 Closure Performance Demonstration....................

60 4.3.3.4 Ground Water Monitoring and Corrective Action Plan........

61 4.3.4 Ground-Wa ter Cleanup..................................

61 4.3.5 Supplemental Standards.................................

62 4.4 Evalua tion Findings.........................................

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4. 5 Re f ere nce s..............................................

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5.0 RADON ATTENUATION AND SITE CLEANUP.........................

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67 5.1 Areas of Review..........................................

5.1.1 Radon Attenuation.....................................

67 68 5.1.2 Processing Site Cleanup 5.2 Acce ptance Criteria........................................

68 5.2.1 Rad on Attenuation.....................................

68 5.2.1.1 Regulatory Requirements............................

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5.2.1.2 Regulatory Guidance...............................

68 69 5.2.2 Processing Site Cleanup 5.2.2.1 Regulatory Requirements............................

69 5.2.2.2 Regulatory Guidance...............................

70 5.3 R e vie w Pr ocedure s.........................................

70 5.3.1 Rad on Attenuation.....................................

70 5.3.1.1 Evaluation of Parameters............................

70 5.3.1.2 Evaluation of Radon Attenuation Model..................

74 5.3.2 Processing Site Cleanup 74 5.3.2.1 Radiological Site Characterization......................

74 5.3.2.2 Standards Used f or Cleanup..........................

75 5.3.2.3 Verification 76 5.4 Evaluation Findings........

76 5.4.1 Radon Attenuation.....................................

76 77 5.4.2 Procemsing Site Cleanoo

5. 5 Re f e rence s..............................................

77 A PPE N DI X A...................................................

A-1 A PPEN DI X B...................................................

B-1 C-1 APPENDIX C..................................................

D-1 APPENDIX D..................................................

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LIST OF TABLES 4

T ABLE 1 - R evie w Ar e a s............................................

TABLE 2 - Maximum Concentration Limits (MCLs).........................

42 TABLE 3 - Common Chemical Mill Constituents...........................

56 TABLE 4 Constituents / Detection Limits for Water Analyses 57 LIST OF FIGURES FIGURE 1 - Schematic of a Typical UMTRA Cover.........................

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1 STANDARD REVIEW PLAN (SRP) - INTRODUCTION l

uranium-Uranium mill tailings are created in the extraction of source material from bearing ore. These mill tailings wastes, from both inactive and active mills pose a long-term hazard to the public health and safety. Congress enacted the Uranium Mill Tailings j

Radiation Control Act of 1978 (UMTRCA), to provide for the disposal, long-term stabilization, and control of these uranium mill tailings in a safe and environmentally sound l

manner.

in UMTRCA, Congress stated its finding that uranium mill tailings "... may pose a potential and significant radiation hesith hazard to the public,... and... that every x

reasonable effort should be made to provide for stabilization, disposal, and control in a safe and environmentally sound manner of such tailings in order to prevent or minimize radon I

diffusion into the environment and to prevent or minimize other environmental hazards i

from such tailings."

The Environmental Protection Agency (EPA) was directed to set "... standards of j

general application for the protection of the public health, safnty, and the environment..."

for directing this process of stabilization, disposal, and control. UMTRCA authorized the Department of Energy (DOE) to conduct necessary remedial actions at 24 designated inactive uranium processing sites to achieve compliance with the standards established by EPA. It also requires NRC to concur in DOE's remedial actions at each site (in Section 108) and to issue licenses for these sites (in Section 104) that may encompass any "...

monitoring, maintenance, or emergency measures necessary to protect public health and safety."

DOE, assisted by the Technical Assistance Contractor (TAC) and the Remedial Action Contractor (RAC), develops and issues a Remedial Action Plan (RAP) to document the proposed remedial action to be implemented at a particular site. The RAP describes the series of activities and presents the proposed design stabilizing the residual radioactive materials at the disposal site. The proposed design and sequence of activities in the RAP should assure long term protection of the public and the environment.

In accordance with UMTRCA Section 108(a)(1), the NRC staff reviews and concurs with the RAP, and any subsequent modifications. By its concurrence in.the remedial _._

action selection, the NRC staff must conclude that the planned remedial actions will comply with EPA's applicable standards in 40 CFR 192, Subparts A, B, and C and 4

provisions in 40 CFR 264 referenced in Part 192. The Technical Evaluation Report (

documents the technical and regulatory basis for the NRC staff's concurrence in DOE's proposed remedial action.

The RAP for a specific site remediation can encompass a number of separate documents that normally consist of the following:

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1) Remedial Action Selection Report

2) Bidder's information - Attachment 1

3) Geology Report - Attachment 2 j

4) Groundwater Hydrology Report - Attachment 3

5) Supporting TAC calculations - Appendices to Attachment 3 l

6) Water Resources Protection Strategy Report - Attachment 4 i

7) RAC calculations (usually multiple volumes)

The Remedial Action Selection (RAS) report provides an overview of the remedial action p;an. The other documents are detailed supporting documents to the RAS report. contains information that will be provided to subcontractors (to the RAC) involved in carrying out the remedial action work. This information usually includes drawings and specifications on the cell construction and site cleanup. Attachment 2 is a l

detailed report on the regional and site-specific geology. Information contained in this report normally includes descriptions of the stratigraphy, but also includes discussions on l

geomorphology and seismology. The Groundwater Hydrology Report provides information on the hydrogeology of both the processing and disposal sites (if they are different),

i including information on the hydrostratigraphy, hydraulic properties, geochemistry, and j

water use. The supporting TAC documents contain calculations and data to support j

conclusions and results presented in the Groundwater Hydrology Report. The Water i

Resources Protection Strategy Report describes how DOE proposes to meet the EPA l

groundwater standards. RAC calculations are usually engineering calculations and supporting information on the disposal cell stability and the cover design.

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When a RAP is received, NRC management will assign a project manager (PM) who will be responsible for compiling the NRC staff's response to DOE. The PM also makes sure that the project stays on schedule. A team of technical staff will be assigned by l

management to review specific aspects of the RAP in their respective technical discipline.

Accentance Review i

l The staff will conduct an acceptance review of the preliminary final RAP to determine the completeness of the information submitted in the RAP. This review is a comparison of 4

i the submitted information to the areas of review discussed in SRP Sections 1.1,2.1,3.1, 4.1, and 5.1 (NRC,19898). The RAP will be considered acceptable; if the provided information is complete, reflects an adequate reconnaissanca and physical examination of l

the regional and site conditions, and provides appropriate analyses and design information to demonstrate that the EPA standards are met.

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i This review can be completed quickly if the RAP contams sufficient information and provides edequete date to support the conclusions such that the staff con make en independent essessment of DOE's assumptions, onelyses, and conclusiones The

'"mussions presented in the RAP should lead the reviewer in a logical menner from j

promises through to the conclusions. The objective of each section of the RAP is to j

describe the technical features that affect the ability of the site and the disposal cell design to comply with the EPA standards. All information, data discussions, interpretations, and conclusions should be directed to this objective, if the staff determines that the RAP is unacceptable for full review, a letter will be prepared and transmitted by NRC management rem sne, nevosow i 2

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unacceptable for full review, a letter will be prepared and transmitted by NRC management to DOE explicitly stating the reasons for the rejection.

RAP Review The staff review of DOE's preliminary final and final RAPS is covered in the following Standard Review Plans (SRP). Basic requirements for NRC's concurrence in DOE's proposed remedial action are established as follows:

1. There must be reasonable assurance of compliance with the EPA control requirements 40 CFR 192 for durability of stabilization and control of radon, and

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protection of groundwater resources in; and

2. There must be reasonable assurance of compliance with the EPA requirements in 40 CFR 192 for cleanup of the processing site.

NRC concurrence is granted, provided that the technical findings presented in the RAP support the conclusions that the proposed remedial action meets the above requirements and is therefore consistent with the applicable EPA standards. The NRC documents their findings and the basis for their concurrence in a TER. Each technical reviewer prepares a portion of the. aport for one or more of the technical areas listed below. These technical sections are organized by the Project Manager (PM) into the complete TER document.

This SRP consists of major chapters addressing each of the areas of review listed below. The primary purpose of the SRP is to help assure that NRC staff review of DOE's Uranium Mill Tailings Remedial Action (UMTRA) project documents are conducted in a thorough, focused, efficient, and consistent manner and that the staff's findings are properly documented. Secondly, the SRP provides DOE, the impacted states and Indian tribes, and other interested parties with an understanding of the NRC review process.

Each SRP chapter has been written to provide the review procedures and acceptance criteria for all of the technical areas pertinent to that chapter. The SRP cannot provide detailed lists of acceptance criteria and step-by-step procedures to be used in every technical review area due to the site-s,. :;ific nature of these reviews. Additional detailis given in those areas that require additional clarification of the NRC staff position. Each chapter of the SRP is organized into five sections as follows:

Areas of Review Tha scope of the technical review is dest ribed in this section. The section contains a brief description of specific technicalinformation and analyses that must be reviewed by each technical reviewer. It also contains a discussion of any information needed (or review expected) from other technical reviewers to permit the primary reviewer to complete the review.

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This section contains a general statement of the purpose for reviewing the specific technical area, and an identification of which standards apply to that review. The basis for j

TABLE 1 - Review Areas

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REVIEW AREA PRIMARY REVIEW TOPICS Geology and Seismology Geologic adequacy of site with respect to EPA stability standards j

Geotechni::al Engineering Adequacy of geotechnical engineering aspects of the site and design with l

respect to EPA stability standards Surface Water Hydrology Adequacy of erosion protection design t

with respect to EPA stability standards Water Resources Protection Adequacy of protection against future i

l groundwater contamination and cleanup of cxisting contamination with respect to l

EPA standards for groundwater protection r

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l Radon Attenuation Adequacy of radon attenuation design i

with respect to EPA radon control l

standards Site Cleanup Adequacy of the program for cleanup of j

j contaminated lands and structures with respect to the EPA cleanup standards f

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l determining the acceptability of the site ch'aracterization or design within the scope of the i

l technical review pertinent to each SRP chapter is also provided. In addition to the regulatory requirements of the EPA Standards, the technical basis may consist of general l

or specific guidance provided in NRC Regulatory Guides, Staff Technical Positions, and I

1.4 Evaluation Findings

If the evaluation by the staff, based upon a complete review of geologic and seismic stability aspects of the remedial action plan documents, confirms that the applicable standards and regulatory guidelines have been met, documentation of the findings will state: 1) that the stratigraphic, geomorphic, seismic and tectonic investigations adequately i

characterize the site and support all conclusions: 2) that the analyses necessary to provide reasonable assurance of long-term geologic stability are acceptable and contain adequate margins of safety, and 3) that, from a geologic point of view, the. general remedial action design represents a feasible plan for meeting with reasonable assurance the long-term stability provision of the EPA standards established by 40 CFR, Part 192, Subpart A.

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Staff reservations about any portion of the RAP wW 6e stated A sufficient detail to make clear ti.e precise nature of the staff concem.

1.5 References Bonilla, M.G., R.K. Mark, and J.J. Lienkaemper, " Statistical Relations among Earthquake Magnitude, Surface Rupture Length, and Surf ace Fault Displacement," Bulletin of the Seismological Society 'of America, vol. 74, pp. 2379-2411.1984.

Campbell, K.W., "Near-Source Attenuation of Peak Horizontal Acceleration," Bulletin of the Seismological Society of America, vol. 71, pp. 2039-2070,1981.

Campbell, K.W., "A Preliminary Methodology for the Regional Zonation of Peak Ground Acceleration," Proc. 3rd international Earthquake Microzonation Conference, Seattle, Washington, pp. 365-376,1982.

Code of Federal Regulations, Title 40, Protection of Environment, Part 192, " Health and Environmental Protection Standards for Uranium Mill Tailings," 1987.

Joyner, W.B. and D.M. Bonre, " Peak Horizontal Acceleration and Velocity from *t.ong Motion Records including Records from the 1979 Imperial Valley, California, Earthquake," Bulletin of the Seismological Society of America, vol. 71, pp. 2011-2038, 1981.

Shannon & Wilson, Inc and Agbabian-Jacobsen Associates, " Soil Behavior Under Earthquake Loading Conditions State-of-the-Art Evaluation of Characteristics for Seismic Responses Analyses," U.S. Atomic Energy Commission Contract W-7405-ENG-26, January 1972.

Slemmons, D.B., " State-of the-Art for Assessing Earthquake Hazards in the United States:

Report 6, Faults and Earthquake Magnitude, " Miscellaneous Paper S-73-1, U.S. Army Engineer Waterways Experiment Station, Corps of Engineers, Vicksburg, Mississippi, 1977.

Slemmons, D.B., P. O' Malley, R.A. Whitney, D.H. Chung, and D.L.Bernreuter,

" Assessment of Active Faults for Maximum Credible Earthquakes of the Southem Califomia-Northem Baja Region," University of Califomia, Lawrence Livermore National Laboratory publication no. UClO 19125,48 p.,1982.

U.S. Nuclear Pegulatory Commissir.,n, " Seismic Hazard Characterization of the Eastern United States: Methodology and Interim Results for Ten Sites " NUREG/CR-3756, Appendix C-A,1984.

- Geomorphic Controls on the Management of Nuclear Waste," NUREG/CR-3276,1983.

- Staff Technical Position - Standard Format and Content for Documentation of Remedia Action Selection at Title i Uranium Mill Tailings Sites", February,1989b.

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i 2.0 - GEOTECHNICAL STABlWTY i

2.1 Areas of Review a

l The RAP and/or its supporting documents must contain geotechnical information and design details related to the proposed disposal site and all materials associated with the remedial action design including soil and rock cover, foundation materials, contaminated materials, and other materials for any zones such as liners, filters, or capillary breaks. The major areas of information that should be presented in the RAP for review by the staff are

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briefly described as follows:

2.1.1 Characterization of Site Stratigraphy and Uranium Mill Tailings information presented in the RAP on the geotechnical aspects of the site stratigraphy and the geotechnical characteristics of the uranium mill tailings designated for stabilization will be reviewed.

Information on geotechnical characteristics of the site and the tailings pile willinclude:

exploration data, test results, description of physical properties, and both static and dynamic engineering parameters of the materials in question, as well as discussion of j

groundwater conditions for all critical subsurface strata at the site, including information l

on the annual groundwater fluctuation.

f 2.1.2 Slope Stability l

Exploration data, test results, slope characterization, and analyses related to the stability of all natural and man-made earth and rock slopes whose failure, under any of the conditions to which they could be exposed throughout the design period, could adversely 1

affect the integrity of the remedial action plan will be reviewed.

I 2.1.3 Settlernent i

The results of testing and analyses conducted to estimate deformation and differential j

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l settlement of subsurface materials and uranium mill tailings under both static and seismic conditions, and the resulting effects on the soil cover will be reviewed.

2.1.4 Liquefaction Potential l

An analysis of the liquef action potential of subsurface and pile material will be reviewed. Consequences of liquefaction of subsurface soils and/or uranium m!!I tailings i

affecting the stability of cover materials and erosion protection layer will also be analyzed.

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2.1.5 Soil Cover Engineering Parameters information provided related to soil cover material, inciading field exploration data, laboratory test results, and design details pertinent to the geotechnical stability aspects of J

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cover design, i.e., cover thickness, compaction requnemens. gradations, permeability, and dispersivity will be reviewed.

2.1.6 Construction Considerations information on the geotechnical aspects of the remedial action construction will be reviewed. These may include details such as: the sequence of construction activities, material placement procedures, and important quality control aspects of the construction.

2.1.7 Radon / Infiltration Barrier Hydraulic Conductivity Testing, calculations, and justification of radon / infiltration barrier design hydraulic conductivity will be reviewed.

2.2 Acceptance Criteria 2.2.1 Regulatory Requirements The basic acceptance criteria pertinent to the geotechnical stability aspects of these reviews is provided ir. EPA's 40 CFR Part 192, Subpart A (EPA, 1987). 40 CFR 192.02 states that:

" Control of residual radioactive materials and their listed constituents shall be designed to:

(a) Be effective for up to one thousand years, to the extent reasonably achievable, and in any case, for at least 200 years, and, (b) Provide reasonable assurance that releases of redon-222 from residual radioactive material to the atmosphere will not:

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Exceed an average release rate of 20 picocuries per square meter per second lover the entire surface of the disposal site and over at least a one year periodl, et (2)

Increase the annual average concentration of radon-222 in air at or above any location outside the disposal site by more than one-half picocurie por liter."

Control is defined in the regulation as "any remedial action intended to stabilize, inhibit future misuse of, or reduce emissions or effluents from residual radioactive materials."

It is the staff's position that the requirements and implementation guidelines of 40 CFR 192 (Subparts A and C and Supplementary information sections) necessitate that due consideration be given to geotechnical parameters. NRC Staff Technical Positions have been developed for Standard Format and Content for Documentation of Remedial Action Selection at Title i Uranium Mill Tailings Sites (NRC,1989b) and for Testing and Inspection Plans During Construction of DOE's Remedial Action at inactive Uranium Mill Tailings Sites (NRC,1989a).

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2.2.2 Regulatory Guidance There is one NRC regulatory guide directly applicable to the geotechnical aspects of the UMTRA program, and two that address geotechnical aspects of site investigations for nuclear power plants which may provide additional guidance on reviewing mill tailing impoundments. These reports are:

(a) Regulatory Guide 3.11 (NRC,1977) " Design, Construction, and Inspection of Embankment Retention Systems for Uranium Mills" - This guide describes some engineering practices and methods generally considered satisfactory for the design, construction, and inspection of earth and rockfill embankments used for retaining l

uranium mill tailings.

(b) Regulatory Guide 1.132 (NRC,1979) " Site investigations for Foundations of Nuclear Power Plants" - This guide describes programs of geotechnical engineering site investigations that would normally meet the needs for evaluating the performance of earthworks under anticipated static and dynamic loading conditions. It provides general guidance and recommendations for developing site-specific investigation programs as well as specific guidance for conducting subsurface investigations, the spacing and depth of borings, and sampling.

(c) Regulatory Guide 1.138 (NRC 1978) " Laboratory investigations of Soils for Engineering Analysis and Design of Nuclear Power Plants" - This guide describes laboratory investigations and testing practices acceptable for determining soil and rock properties and characteristics needed for geotechnical engineering analysis and design.

2.3 Review Procedures The following is a brief description (by review areal of the general procedures for soview conducted by the staff in evaluating the geotechnical stability aspects of the RAP supporting a proposed UMTRA project. Publications that are typically used in this review are listed in Section 2.5.

2.3.1 Characterization of Site Stratigraphy and Uranium MillTailings Using appropriate references listed in Section 2.5, and other sources, the staff will review the information presented and field investigations performed to characterize the site stratigraphy and the geotechnical properties cf the tailings materials. The staff will determine whether all the necessary information has been provided pursuant to the guidelines of the Standard Format and Content (NRC,1989b). The information on site stratigraphy and tailings materials will be acceptable if its scope and level of detail is commensurate with the influence such information has on the determination that the remedial action will comply with 40 CFR 192.

The following questions will be considered in the review:

(a) is the regional stratigraphy defined in sufficient detail such that it provides a clear

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i perspective and orientation to the site-specific subsurface information?

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(b) Are the exploratory techniques used by the site inves99ator consistent with current practice? Do the samples represent the in situ soil conditions?

i (c) Do the investigations provide coverage of the site and borrow material areas in sufficient detail to define the specific subsurface conditions with a high degree of i

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confidence?

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(d) Have all soils that might be unstable because of their physical or chemical properties been identified and adequately evaluated?

2 (e) Are the investigations performed (including laboratory and field testing) sufficient to j

establish the engineering parameters of borrow materials, tailings, and underlying soil and rock materials at the site?

1 (f) Have the records of the historic fluctuations of ground water at the site as obtained 1

from monitoring local wells and springs and/or by analysis of piezometer and j

permeability data from tests conducted at the site been presented in sufficient detail to effectively incorporate the information into geotechnical stability analyses? This aspect of the review is coordinated with the hydrogeologic characterization review performed j

under Chapter 4 of this SRP.

The borrow material exploration program will be reviewed for its adequacy to support a determination of the suitability of borrow material for a specific use. The procedure for restoration of the borrow area will be reviewed for its effect on the performance of the stabilized tailings pile, particularly its effect on the site drainage, ground water table, and overalllong-term stability of the tailings.

I In meeting the general regulatory positions of Regulatory Guedes 1.132 and 1.138, the determination of engineering properties of underlying materials at the site, uranium mill j

tailings, and borrow materials will be considered acceptable by the reviewer if applicable i

l methods are properly used in characterizing the materials. Tt e test data obtained should be consistent with the needs of the proposed remedial action at the site. The test i

methods are described, for example, in geotechnical journals published by the American Society of Civil Engineers, applicable standards published by the American Society for

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Testing and Materials, institution of Civil Engineers, and various research reports prepared l

by Universities. The parameters of the materials must be supported by field and laboratory j

l test records.

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The staff will determine that a detained discussion of laboratory sample properation has been provided when applicable. For criticallaboratory tests, details such as how saturation of the sample was determined and maintained during testing, or how the pore j

pressures changed should be given.

The staff review should determine that the RAP appropriately presents a detailed and

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quantitative discussion of the criteria used to verify that the samples were properly taken and tested in sufficient number to define all the critical soil parameters for the site. For

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sites that are underlain by saturated soils or sensitive clays, it should be shown that all zones which could become unstable due to liquefaction or strain softening phenomena have been adequately sampled and tested. Dispersive characteristics of the soil should be investigated, if applicable. The test program and discussion should also show that the consolidation behavior of the soils, as well as their static and dynamic strength parameters, have been adequately defined. The reviewer should determine that the RAP appro.oriately explains how the developed data are used in the analyses, how the test data are enveloped for design, and why the design envelope is conservative, and that the RAP includes a table indicating the value or range of values of the parameters used in the i

j analyses.

To determine whether sufficient investigations were performed, the staff will evaluate the effectiveness of the boring, sampling, and testing programs in defining the specific site conditions pertinent to all analyses and design necessary to demonstrate that the remedial action plan meets the stability standards. If it is the staff's judgment that the investigations or testing are inappropriate or insufficient, additional investigations may be requested. The final conclusion will be based in part on professional judgment, considering the complexity of the site subsurface conditions. As part of the review, the staff must ascertain that appropriate laboratory and field techniques and equipment are employed in determining the material parameters.

2.3.2 Slope Stability Plot plans, cross sections, and profiles of slopes of the tailings pile and all nearby slopes, the failure of which could adversely affect the stability of the remedial action plan, will be reviewed and compared with exploratory records and provisions of the RAP to ascertain that the most critical conditions have been addressed and that the characteristics of all slopes have been adequately defined. The soil and rock test results will be reviewed to determine if there is sufficient relevant test data to support the selection of the soil strength characteristics used in the slope analysis. The review will also consider whether appropriate soil and rock characteristics derived from the investigations have been completely and conservatively incorporated into the design. The discussion of characteristics of critical slopes at the site will be considered acceptable by the reviewer if it includes:

(a) Cross-sections and profiles of the slope in sufficient number and detail to represent all significant slope and foundation conditions.

(b) A summary and description of static and dynamic properties of the soil and rock comprising the slope and a discussion of procedures used to estimate, from the available field and laboratory data, conservative soil parameters and profiles to be used in the analysis.

(c) A summary and description of the ground water conditions within or beneath the slope.

The reviewer will consider the discussion of the stability analysis satisfactory if valid static and dynamic analyses have been presented to demonstrate that there is an adequate w 22.1993 4

19 FMAL SMP. REVism 1 i

i

margin of safety. If the safety factors resulting from the analysis are not appropriate for the hazards posed by a slope failure, or if clearly unconservative soil properties were used, l

the staff will request additional data to verify the assumptions.

The criteria and methods of analysis will be reviewed to ascertain that appropriate techniques have been employed. The slope analyses will be reviewed to determine that an

[

appropriately conservative approach has bee,n used, and that all adverse conditions to j

which the slope might be subjected have been considered. A number of different methods l

of analysis are available in the literature. To be acceptable, the static analyses should include calculations with different assumptions and methods of analysis to assess the following:

(1) The uncertainties with regard to the shape of the slope, the boundaries and parameters of the several types of soils within the slope, the forces acting on the slope, and the pore pressures acting within the slope.

1 i

(2) Failure surfaces corresponding to the lowest factor of safety.

(3) The effect of the assumptions inherent in the method of analysis used.

No single method of analysis is entirely acceptable for all:tability assessments; thus, no single method of analysis is recommended. Relevant manuals issued by public agencies (such as the U.S. Navy Department, U.S. Army Corps of Engineers, and U.S. Bureau of Reclamation) are often used in reviews to ascertain whether the analyses performed are reasonable (see list of references). If any of the important interaction effects cannot be included in a given analysis, such effects must be treated in some approximate but conservative fashion. The engineering judgement of the presenter will be given strong consideration in the staff's review of the analyses and in assessing the adequacy of the j

resulting safety factors. The dynamic stability of slopes will be reviewed considering the maximum credible earthquake and potential site amplification of ground motions.

To be acceptable, the dynamic analyses must account for the effect of dynamic stresses of the MCE on soil strength parameters. Similar to the static analyses, the various parameters such as geometry, soil strength, and hydrodynamic and pore pressure forces, should be varied to show that there is an adequate margin of safety. Pseudostatic analyses in lieu of the dynamic analysis are acceptable if the strength parameters used in the analyses are conservative, the materials are not subject to significant loss of strength and development of high pore pressures under dynamic loads, and the resulting minimum factor of safety suggests an adequate margin. The design seismic coefficient to be used in the pseudostatic analysis should be either 67 percent of the peak acceleration of the MCE at the foundation level of the tailings pile or O.10, whichever is greater. If the design seismic coefficient is greater than 0.20, then the dynamic stability investigation may be augmented by other appropriate methods (i.e., deformation method, finite element method), depending on specific site conditions.

If the staff review indicates that questionable assumptions have been made or nonstandard or inappropriate method of analysis has been made, the staff may model the slope in a manner consistent with the data, and perform an independent analysis.

u. 22.Soss Fu sw. mvism i 20

l 2.3.3 Settlement The settisment of the remediated tailings as a result of volume change of the soils and rock beneath the pile, and volume change of the tailings pile as a result of its self-weight and weight of cover materials are to be evaluated by appropriate methods. The discussions of settlement analyses will be considered acceptable if the settlement of subsurface materials and the tailings has been analyzed to include: rebound, settlement, and differential settlements (caused by zones of slimes, the varying material thicknesses, and the heterogeneous nature of the pile) under the loads of fill and of seismic loading. In general, the review procedure will include:

(a) Determining whether the soil and rock parameters used in the settlement analyses represent the in situ condetions at the site. The site investigation, sampling, and laboratory test programs must be adequate to support this determination. The stratigraphy used in the analysis, particularly the location of siimes zones within an embankment, will be reviewed.

1 (b) Determining whether the methods of settlement analyses are appropriate for the tailings embankment, and soil conditions at the site. Contributions to settlement by drainage of mill teilings and by consolidation / compression of slimes and/or sands are reviewed. Both is.stantaneous and time dependent components of total and differential settlements will be verified. An analysis of the potential for development of cracks in the earth cover (radon barrier) as a result of differential settlements will be reviewed.

(c) Determining whether the total and differential settlement estimates represent conservative and tolerable behavior of the remediated pile.

2.3.4 Liquefaction Potential Liquefaction potential will be reviewed by a study of the results of geotechnical investigations including boring logs, laboratory classification test data, and soil profiles to determine if any of the site soils or the tailings pile material could be susceptible to liquefaction. The results of in-situ tests such as the standard penetration test along with density and strength tests on undisturbed samples obtained in exploration borings will be exammed. Ground water conditions will be reviewed. The analysis of the expected maximum ground acceleration and the potential for soil amplification will also be reviewed.

Alternatively, post-earthquake stability methods based on residual strengths, and deformation analysis, may be utilized to exam'me liquefaction.

If it is determmed that there may be lique.f action-susceptible soils beneath the site or in the teelmos pile; the site exploration methods, laboratory test program, and analysis will be reviewed for adequacy and reasonableness. When the need for an 'm-depth analysis is indicated, an assessment of the potential adverse effects that complete or partial liquefaction could have on the stability of the embankment may be based on cyclic triaxial test data obtained from undisturbed soil samples taken from the critical zones in the site area. The liquefaction potential analysis will be reviewed in detail and compared to an independent study performed by the staff,if necessary, h 22 "88 21 ma sar. nevnem i

2.3.5 Soil Cover Engineering Parameters The staff will review the following geotechnical stability aspects of the earthen cover:

(a) Determine that an adequate quantity of the specified borrow material has been identified at the borrow source.

(b) Ascertain that placement density, specific gravity, moisture content, dispersivity and shnnkage proportes used in the soil cover design have been determined by suitable laboratory testing such that long-term stability standards will be met. Note that permeability issues are discussed separately in Section 2.3.7.

(c) Verify that the particle size gradation of the earth cover, bedding layers, and the rock layer are compatible to assure their stability against particle migration during the design life.

(d) Determine that the cover has been designed to accommodate the effects of anticipated freeze-thaw cycles.

(e) Determine, if bentonite amendment to the radon barrier is proposed, that supporting discussions appropriately address laboratory testing and field procedures associated with amended materials.

(f) Determine if the cracking potential of the cover has been adequately addressed. Both cracking due to settlement and shrinkage should be evaluated. In the past, NRC has favorably reviewed cracking potential calculations performed as described by Lee and Chen (subsidence) and Spangler and Handy (shrinkage). Other reasonable solutions will also be considered.

Review of the redon attenuation aspects of the cover design is addressed in the SRP Chapter 5, Redon Attenuation.

2.3.6 Construction Considerations The geotechnical aspects of the planned construction operations will be reviewed to identify any related design flaws or deviations from standard engmeenng practice for earthworks. The review will ascertain if all the tailings and contammeted materials at the site can be placed within the configuration of the proposed stabilized pile. The construction sequence will be reviewed to verify the feasibility of achieving the intended final configuration of the teelmes, particularly when tailings are to be relocated to new areas of the remeduted pile. Meterial placement procedures, includmg procedures intended to achieve the desired moisture content (dryme, if needed) and placement density and permeability are reviewed. If mixing of the fine tailings (sismos) with send tainmes is proposed, the specifications to control the mixture and determ'metion of engineenne properties of this mixture will be reviewed.

Aspects of proposed quality control will be reviewed to verify that adequate provisions FMAL SRP. REVIS40N 1 22 Jua= 22. 5 '*2 I

s I

have been included to ensure that the construction will be in accordance with the RAP. In particular, details of the testing and inspection program, including type and frequency of tests proposed, will be reviewed and compared to NRC guidance on testing and inspection (NRC,1989a).

2.3.7 Hydraulic Conductivity The geotechnical design aspects of the cover will be reviewed to ensure that the radon / infiltration barrier component of the layered cover has a minimal hydraulic conductivity, to limit radon emissions from, and water infiltration into, stabilized mill tailings. The review will verify if the hydraulic conductivity has been minimized by compacting fine-grained soil for a sufficient depth above the stabilized tailings. Natural borrow soils having insufficient silt and clay content to effectively reduce the barrier's hydraulic conductivity can be amended with ber$ tonite for improved effectiveness.

In response to the Environmental Protection Agency groundwater standards, designers of radon / infiltration barriers for mill tailings sites are proposing increasingly limited design hydraulic conductivity (k) values. It is not unusual for laboratory permeability test values to yield results of 10* to 10" cm/sec. Such tests are performed on compacted soil samples considered by the design engineer to represent the soil to be used for the radon / infiltration barrier.

Several recent technical papers (Goode, et. al.,1986; Rogowski,1990; Panno, et. al.,

1991; and Benson and Daniel,1990) have raised serious questions on the exclusive use of 1

laboratory testing for demonstrating hydraulic conductivity values in those cases where a radon barrier k-value less than 10 cm/sec is specified. Based on a review of these 4

technical papers, field testing is necessary since construction operations and soil material variability can create preferred pathways, joints, seams, holes, and flaws that effectively increase a barrier's hydraulic conductivity. According to Daniel (1990), the hydraulic conductivity may be underestimated by an order of magr.itude or more".

The review staff shall verify that a rational basis for the design hydraulic conductivity (k) value for the radon / infiltration barrier has been provided in the RAP. For any situation in which k< 10 cm/sec is specified, the staff shall verify that either: (1) a test fill program 4

will be undertaken to verify the constructibility; or (2) the RAP narrative and accompanying analyses have adequately demonstrated why the recent technical papers are not relevant for the site specific low k value. If the RAP demonstrates why field testing is not required, the reviewer shall provide the rational basis in the TER for not requiring field testing at a specific site. If field testing is required, staff should ensure that the test fill specifications require that the hydraulic conductivity value be verified by in-place testing with double-ring infiltrometers or other approved methods. The test fill construction plan and verification program will be reviewed for adequacy by staff.

For all cases where k < 10 cm/sec and the test fill program requirement has been 4

defined, specifications and related documents (RAIP, etc.) shallinclude a strict quality control program. An acceptable OC program should provide a mechanism (s) to ensure that as-built construction duplicates the test fill construction technioues on the cell barrier. The

>u'= 2 2.1 *S 3 FIPdAt SRP, REVISKm i 23

objective of the QC program will be to provide assurance that urnform and construction of the cell barrier has been achieved.

2.4 Evaluation Findings

if the evaluation by the staff, based upon complete review of geotechnical stability aspects of the remedial action plan documents, confirms that the applica

1) that the regulatory guidelines have been met, documentation of th characterizing the substrata, tailings and borrow materials; 2) that the analyses neces to provide reasonable assurance of long term geotechtscal stability are acce contain adequate margins of safety, and 3) that the general remedial action design represents a feasible plan for meeting with reasonable assurance the long-ter provision of the EPA standards established by 40 CFR, Part 192, Subpart A. St reserMtions about any portion of tho RAP will be stated in sufficient detail to make the precise nature of the staff concern.

.2,5 References Benson, C.H. anc' Daniel, D.E. (1990), influence of Clods on Hydraulic Conductivi Compacted Ceay" Code of Federal Regulations, Title 40, Protection of Environment, Part 192,* Healt Environmental Protection Standards for Uranium Mill Tailings," 1987.

Daniel, David E., " Compacted Clay and Geosynthetic Clay Linings

Daniel, D.E. and Benson, C.H., " Water Content-Density Criteria for Compacted 1990.

Formulk, N. and Haug, M., (1990), Evaluation of in-Situ Permeability Testing Me Geotechnique, The institution of Civil Engineers, London.

Goode, D., Young, M., Weber, M., Forstrom, J., (1986), "Information on Permeabili Testing of Soil Covers and Liners" Journal of the Geotechnical Engineering Division, Proceedings of the Americ Civil Engineers.

Lee, K.L., and Shen, C.K., " Horizontal Movements Related to Subsidence Mechanics and Foundation Division, Volume 95, No. SM-1, ASCE, New York, 1969.

Panno, S.V., Herzog, B.L., Cartwright, K., Rehfeldt, K.R., Krapac, l.G., and H (1991), Field-Scale investigation of infiltration Ir.to a Compacted Soit Liner" Rogowski, A.S., (1990), " Relationship of Laboratory and Field-Determined Jua" 2 2

8 24 FD6AL SRP. fEVtS00N 1

m

.-_.a

-a m

.-_.,a

_.-_e Conductivity in Compacted Clay Liner" Shannon & Wilson, Inc. and Agbabian-Jacobsen Associates, ' Soil Behavior Under Earthquake Loading Conditions State-of the-Art Evaluati a of Characteristics for Seismic Responses Analyses," U.S. Atomic Energy Commission Contract W-7405-eng-26, January 1972.

Spangler, M.G., and Handy, R.L., Soil Enoineerina. Harper and Row, Publishers, New York, 1982.

Stagg, K. and O. Zienkiewicz, " Rock Mechanics in Engineering Practice," John Wiley &

Sons,1968.

Terzaghi, K. and R. B. Peck, " Soil Mechanics in Engineering Practice," 2nd ed., John Wiley

& Sons,1967.

U.S. Army Corp of Engineers, " Soil Sampling," Engineering Manual EM1110-2-1907, March 1972.

- Instrumentation of Earth and Rockfill Dams, Engineering Manual EM1110-21908,Part 1 and 2," August and November,1971.

" Laboratory Soil Testing," Engineering Manual EM 1110-2-1906, November 1970.

-- Engineering and Design Stability of Earth and Rock Fill Dams," Manual N. EM 1110 "

1902, Office of the Chief of Engineers, Dept. of the Army,1970.

U.S. Bureau of Reclamation, " Earth Manual," First Edition, U.S. Dept. of Interior,1968.

U.S. Department of the Navy, " Soil Mechanics," NAVFAC DM 7.1, May,1982

- Foundations and Earth Structures," NAVFAC DM 7.2, May,1982

- Soil Dynamics, Deep Stabilization, and Special Geotechnical Construction," NAVFAC DM 7.3, May 1982.

U.S. Nuc! ear Regulatory Commission, Regulatory Guide 1.132, " Site Investigations for Foundations of Nuclear Power Plants," Revision 1, March 1979.

-Regulato y Guide 1.138, " Laboratory inve tigations of Soils for Engineering Analysis and Design of Nuclear Power Plants," April 1978.

-Regulatory Guide 3.11, " Design, Construction, and Inspection of Embankment Retention Systems for Uranium Mills," Revision 2, December 1977.

--- Rock Riprap Design Methods and Their Applicability to Long-Term Protection of Uranium Mill Tailings impoundments," NUREG-2684, August 1982.

June 22.ieos 25 F04AL SAP, REVIS60N 1

.(

4

- Consolidation of Tailings," NUREG-3204, October 1983a.

- Guidance for Disposal of Uranium Mill Tailings: Long-Term Stabilization of Earthen 3

Cover Materials," NUREG-3199, October 1983b.

- Design Considerations for Long-Term Stabilization of Uranium Mill Tailings impoundments," NUREG-3397, October 1983c.

l

- Geomorphic Controls on the Management of Nuclea-Waste," NUREG/CR-3276,1983d.

- Geotechnical Quality Control: Low Level Radioactive Waste and Uranium Mill Tailings i

Disposal Facilities," NUREG 3356,1983e.

)

- Staff Technical Position on Testing and Inspection Plans During Construction of DOE's l

Remedial Action at inactive Urar.ium Mill Tailings Sites", January,1989a.

q

- Staff Technical Position - Standard Format and Content for Documentation of Remedial Action Selection at Title 1 Uranium Mill Tailings Sites", February,1989b.

FWAL SRP. REVIS80N 1 26 m 22,i m u-

a a-

.--e L--

3.0 SURFACE WATER HYDROLOGY / EROSION PROTECTION 3.1 Areas of Review The NRC staff will review hydrologic information, analyses, and design details presented in the RAP and/or its supporting documents to assure the plan provides long-1 J

term erosion protection in accordance with the EPA standards for stability (40 CFR, Part 192, Subpart A). The major areas of review in the long-term erosion protection aspects of i

the design are briefly described in the following sections.

3.1.1 Hydrologic Description of Site The staff will review the following hydrologic site characterization information:

(1) identification of the relationships of the site to surface water features in the site area, and (2) identification of mechanisms, such as flood and dam failures, that may require special design features to be implemented.

This review requires identification of the hydrologic characteristics of streams, lakes (e.g., location, size, shape, drainage area, etc.), and existing or proposed water control structures that may adversely affect the long-term stability of the site design.

3.1.2 Flooding Determinations The staff will review the assessment of the flooding potential for each site, including a determination of the precipitation potential, the precipitation losses, the runoff response 4

characteristics of the watershed, the accumulation of finod runoff through river channels and reservoirs, the magnitude of the probable maximum flood (PMF) or project design flood (if a flood less than the PMF is used) at the site, and the critical water levels, shear stresses, and velocity conditions at the site. The staff also will review: (1) the analyses and justification for the use of a flood less than the PMF, (2) the probable maximum precipitation (PMP) potential, and resulting runoff, for site drainage and for drainage areas adjacent to the site, and (3) the modeling of physical rainf all and runoff processes to estimate possible flood conditions at the site.

The assessment of flooding also willinclude a review of possible geomorphic changes that could affect the potential for flooding and erosion at the site. As applicable, the staff will review the following: (1) identification of types of geomorphic instability; (2) changes l

to, and impacts associated with, flooding and flood velocities due to geomorphic changes; and (3) mitigative procedures to reduce or control geomorphic instability.

The assessment of flooding also willinclude a review of potential dam failures, if upstream reservoirs exist. Peak water levels, flood routing procedures, and velocities will be reviewed in the determination of potential hazards due to failure of upstream water June 22,1993 FINAL SRP. REVi$lON 1 27

1 i

l control structures from either seismic of hydrologic causes. If an existing analysis concludes that seismic or hydrologic events will not cause failures of upstream dams and produce the governing flor >d at the site, the analysis will be reviewed to assure that information which supports such a conclusion (e.g., record of contact with dam designers) i

)

is included. If an analysis is provided that concludes that a dam failure flood due to a PMF or a seismically-induced flood ir, the design basis flood, the computations will be reviewed to assure that appropriate and/or conservative model input parameters have been used.

3.1.3 Water Surface Profiles, Channel Velocities, and Shear Stresses l

Depending on the type of computational models used, the staff will review the model, j

including the determination of flooding depths, channel velocities, and/or shear stresses used to determine riprap sizes needed fo; erosion protection. The staff will review the various detailed computations for each model and will review the acceptability of the input parameters to the model.

3.1.4 Erosion Protection Design Design details and analyses pertinent to the following aspects of erosion protection will be reviewed, as applicable:

(1) Erosion protection against the effects of flooding from nearby large streams.

(2) Erosion protection for drainage and diversion channels.

i (3) Erosion protection for the top and side slopes of the pile.

(4) Erosion protection for the apron / toe area of the side slope.

(5) Durability of the erosion protection.

l (6) Construction considerations, including specifications, quality assurance programs, quality control programs, and inspection programs.

3.1.5 Design of Unprotected Soll Covers and Vegetated Soil Covers If an unprotected soil cover or a vegetated soil cover is proposed, the following design details, calculations, and analyses will be reviewed:

(1) Determination of allowable shear stresses and permissible velocities for the cover.

(2) Determination of allowable shear stresses and permissible velocities for the cover in a degraded state, including the effects of fires, droughts, vegetation succession, and other impacts to the ability of the cover to function without maintenance.

(3) Information on types of vegetation proposed and its ability to survive natural phenomena.

June 22,1993 l

28 FINAL SFtP, PlEVISION 1 4

_.m (4) Information, analyses, and calculations of allinput parametars to models used.

3.2 Acceptance Criteria 4.2.1 Regulatory Requirements The basic acceptance criteria pertinent to the erosion protection aspects of these reviews is provided in EPA's 40 CFR Part 192, Subpart A. 40 CFR 192.02 states that:

" Control of residual r6dioactive matorisis and their listed constituents shall be designed to:

(a) be effective for up to one thousand years, to the extent reasonably achievable, and in any case, for at least 200 years and (b) provide reasonable assurance that releases of radon-222 from residual radioactive material to the atmosphere will not:

(1) exceed an average release rate of 20 picocuries per square meter per second, or (2) increase the annual average concentration of radon-222 in air at or above any location outside the disposal site by more than one-half picocurie per liter."

Control is defined in the regulation as "any remedial action intended to stabilize, inhibit future misuse of, or reduce emissions or effluents from residual radioactive materials."

3.2.2 Regulatory Guidance NRC regulatory guides have not been developed which are directly applicable to the surface water hydrology aspects of the JMTRA program. However, there are staff technical positions that may provide generic guidance in this area. These reports are:

(a) Final Staff Technical Position (FSTP) (NRC,1990) " Design of Erosion Protection Covers for Stabilization of Uranium Mill Tailings Sites."

(b) Staff Techn'. cal Position (NRC,1989b) " Standard Format and Content for Documentation of Remedial Action Selection at Title i Uranium Mill Tailings Sites."

The Final Staff Technical Position, in particular, discusses acceptable methods for designing erosion protection to provide reasonable assurance of effective long-term control and thus meet the EPA standard. The FSTP also provides discussions and technical bases for use of specific criteria to meet the 1000-year longevity requirement, without the use of active maintenance.

FINAL SRP. PIEVISION 1 29 aun.22.ines

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3.3 Review Procedures 3.3,1 Hydrologic Description of Site i

The information normally presented is not amenable to independent verification, except through cross-checks with available publications related to hydrologic characteristics of the site region and through observation during site visits. The review procedure consists of evaluating the completeness of the information and data, by sequential comparison with i

information available from referenca. Based on the description of the hydros)here (e.g.,

geographic location and regional hydrologic features), potential site flood mechanisms are identified.

The staff also will analyze geomorphic considerations, as described in SRP Section 1.

i Based on these analyses, the staff will estimate the potential for geomorphic changes to occur and to have a significant effect on the ability of the site and its protective features to 7 vent flood intrusion and erosion of the tailings over a long period of time. If g-phic problems are identified, the staff will give particular attention to several areas i

of lesign, depending on site conditions and potential for geomorphic changes to occur.

l Th areas include: (1) the apron and toe of the disposal cell; (2) intersection of natural i

su.

with erosion protection features, such as a diversion channel, and (3) diersion channel outlets. A detailed discussion of the erosion protection design for these and other features is given in SRP Section 3.3.4, below.

Acceptance of the information presented is based on a qualitative evaluation of the completeness and quality of information, data, and maps. The description of structures, facilities, and erosion protection designs should be sufficiently complete to allow independent evaluation of the impact of flooding and intense rainfall. Site topographic maps should be of good quality and of sufficient scale to allow independent analysis of prc and post-construction drainage patterns.

3.3.2 Flooding Determinations The staff will estimate the flood levels, velocities, shear stresses, and magnitudes, as described below. Staff estimates may be made independently from basic data, by detailed review and checking of the RAP analyses, or by comparison with estimates made by others that have been reviewed in detail. The evaluation of the adequacy of the estimates is a matter of engineering judgment, and is based on the confidence in the estimate, the degree of conservatism in each parameter used in the estimate, and the relative sensitivity of each parameter as it affects the flood level or flood velocity.

The evaluation of flooding is, for review purposes, separated into two parts: (1) flooding on large adjacent streams, as applicable, and (2) flooding on local drainage channels and protective features. The acceptability of using the PMF as the design flood event is presented in the FSTP. The review procedure for evalusting a PMP/PMF event is outlined in the FSTP. For large drainage areas, PMF estimates approved by the Chief of Engineers, Corps of Engineers, and contained in published or unpublished reports of that i

f agency, or generalized estimates may be used instead of independent staff-developed j

FWAL SRP. REVISION 1 30

u. n. m

4 estimates. The staff will utilize flood estimates developed by Crippen and Bue (1977) and by the U. S. Bureau of Reclamation (1986) to determine historic regional floods, if the historic maximum floods exceed the proposed PMF estimates, the staff will perform a detailed l

evaluation to determine the reasons for the discrepancies: the staff will compare basin lag times, rainfall distributions, soil types, ar'd infiltration loss rates t(s determine if there is a 1

logical basis for the PMF values being less than historic floods. Without such estimates, the staff will generally use Corps of Engineers' runoff, impoundment, and river routing models to independently estimate PMF discharge and water levels at the site, if a computer model such as HEC-1 is used, the staff will review the adequacy of the various drainage area, input parameters to the model, including but not limited to the following:

lag times and times of concentration, design rainfall, incremental rainfall amounts, temporal distribution of incremental rainfall, and runoff / infiltration relationships. When 1

detailed independent estimates are necessary, the applicant will be requested to provide all necessary basic data not already included in the supporting documents.

Information pertinent to computation of the design flood should be submitted in sufficient detail to enable the staff to perform an independent flood estimate. Acceptance of the analysis is based on; acceptability of model input parameters; general agreement of the staff's and the RAP estimates of flood levels and oeak discharges; and the adequacy of the computational methods used for such estimates.

l For dam f ailures, the staff will review the analyses provided in the RAP or sill independently estimate the peak flows at the site. The acceptable " worst conditions" that l

(1) an approximate 25-should be postulated in the analysis of upstream dam failures are:

year flood on a normal operating reservoir pool level coincident with the dam-site equivalent of the earthquake for which the remedial action project is designed; (2) a flood of about one-half the severity of a PMF on a normal reservoir pool level coincident with the i

dam-site equivalent of one-half of the earthquake for which the remedial action project is designed; and (3) a PMF (or design flood) on a normal reservoir pool. Conditions (1) and (2) are applied when the dam is not designed with adequate seismic resistance; condition (3) is applied when the dam is not designed to safely store or pass the design flood.

Often, it may be much easier to perform simplified flood analyses assuming a dem failure, rather than detailed analyses of the seismic resistance of a dam, in such cases, the staff will review those simplified flood analyses by the procedures outlined in Section 3.3.4,

below, in those cases where it is documented that it is clearly impractical to design erosion protection features for an occurrence of the PMF, the staff will evaluate the informat provided in the RAP as follows:

(1) The staff will review several proposed designs (of varying slopes, configurations, alignments, drainage areas, etc.) to (a) determine the difficulties in providing a reasonable design at a given site, (b) determine that reasonable designs have been identified, and (c) determine that the designs are impractical.

(2) The staff will review erosion protection requirements associated with each of the t

w 2t ma 31 r W4 AL TAP, SEVISION 1 l

l e

~

i above designs.

4 i

(3) The staff will review the costs (including transportation) associated with each design.

(4) The staff will review the analyses and logic that justify the reduction in flood criteria.

1 (5) The staff will review the flood design bases and design of protective features with i

respect to the ability of the design to satisty the EPA minimum stability requirement of 200 years.

l 1

l (6) The staff will review the ability of readily-available erosion protection materials to i

satisfy design requirements.

1 4

l Additional information regarding justification of a stability period of less than 1000 years can be found in the FSTP. In general, a proposed design based on less than a PMF l

event must provide reasonable assurance of meeting the EPA stability requirement of 200 i

years. The ability of the design to resist such flood events is independently checked and evaluated by the staff to assure that minimum EPA standards are met.

L l

In the detailed review of flooding, the staff will carefully consider several factors that are important in determining a local PMP/PMF event. These factors include:

1 (1) Determination of Design Rainfall Event. The staff will consult r.ppropriate j

Hydrometeorological Reports and determine that correct vetues of the one-hour and six-i hour PMP events, as applicable, have been determmed, i

l (2) Infiltration Losses. The staff will check calculations to verify that conservative values i

of infiltration have been selected.

l (3) Times of Concentration. The staff will verify that appropriate methods (depending on i

the slope, configuration, etc.) have l, en selected. The staff will independently verify that the methods selected compare reasonably well with various velocity-based methods of design.

t (4) Rainfall Distributions. The staff will verify that the rainfan distributions (particularly the l

2%-minute, 5-minute, and 15-minute distributions) compte well with the distributions suggested in the FSTP.

4 For dem failures, the acceptability and conservatism of the RAP estimate of flood l

potential and water levels are reviewed. In general, depending on the potential for flooding, the staff will verify that the RAP dem f ailure analyses are either realistic or i

conservative by determining locations and sizes of upstream dams assuming an instantaneous failure (complete removal) of the dam embankment and computing the peak j

outflow rate.

i If this simplified analysis indicates a potential flooding problem, the analysis may be I

repeated using more refined techniques, and additional information and data may be requested. Detailed failure models, such as those of the Corps of Engineers and National i

roeat sar. novesioes i 32

u. :. im 1

1 i

l Weather Service are utilized to identify the outflows, failure modes, and resultant water levels at the site.

l If a flood less than a PMF can cause dam failure and is proposed as the design basis flood, the review procedures outlined above are employed to determine the impracticality of designing for a PMF and to determine the acceptability of the flood used.

i 4

i 3.3.3 Water Surface Profiles, Channel Velocities, and Shear Stresses l

Using the guidance presented in the FSTP, the staff will verify that localized flood depths, velocities, and shear stresses used in models for rock size determination (such as i

the Safety Factors Method or the Stephenson Method) are acceptable. For offsite flooding i

effects, the staff will verify that computational models (such as HEC-2) have been correctly and appropriately used and that the output from the model has been correctly j

interpreted. The staff will verify that acceptable models and input parameters have been l

used in all of the various portions of the flood analyses and that the resulting flood forces have been acceptably accommodated. Information regarding acceptable models may be found in the FSTP.

4 i

3.3.4 Erosion Protection Design i

The staff will check the RAP analyses or perform independent review analyses of l

floods, flood velocities, and rock durability according to the guidelines provided in the FSTP. If the design assumptions and calculations are reasonable, accurate, and/or compare favorably with independent staff estimates, the designs are found acceptable.

f.

Depending on the designs proposed, the staff will review erosion protection designs for the following areas: (1) top clope: (2) side slope; (3) apron / toe: (4) diversion channel; and

)

(5) diversion channel outlet. Specific review procedures and acceptance criteria for each af these areas are discussed below, including areas of particular concem and importance.

1 3.3.4.1 Top Slope Because the use of the Safety Factors Method (Simons and Senturk,1977) provides an l

acceptable computation method for design of erosion on relatively flat slopes, the staff will review input parameters to the model according to the recommendations given in the FSTP and referenced technical procedures. The staff will assess the design flow rate, the depth of flow, angle of repose, specific gravity, and other parameters, t

3.3.4.2 Side Slope l

The staff will review parameters to acceptable models, such as the Stephenson Method (Stephenson,1979), similar to those listed in Section 3.3.4.1, above.

l 3.3.4.3 Apron / Toe i

The review of the design of the apron and toe is accomplished by verifying that several l

J== 22. nos r NAL sne, nevisioN t 33 i

j

design features in this area have been properly designed.

For the lower end of the side slope where it meets the toe, the staff will verify that proper consideration has been given to the potential occurrence of increased s resulting from turbulence and energy dissipation produced by hydraulic jumps whe flow transitions from supercritical to subcritical. The staff will verify that appropriate design criteria (such as that used by the Corps of Engineers in their Hydraulic Desi Criteria manual) have been used to increase the rock size to accou velocities or shear forces.

For the main area of the too, the staff will assure that appropriate methods have been used to design the riprap, depending on the magnitude of the slope of the toe.

For the downstream and of the toe, tne staff will verify that acceptable assumptions have been made regarding the assumed collapse of the rock into scoured areas to preve gu'!y intrusion into the pile. Flow concentrations, collapsed slopes, and compu models used by the applicant will be evaluated.

For the natural ground area at the downstream end of the toe, the staff will verify that appropriate methods have been used to compute scour depths and that natura not adversely affect long-term stability.

3.3.4.4 Diversion Channels Using the criteria and guidance presented in the FSTP, the staff will evaluate the design of diversion channels in several critical areas.

For the main channel area, the staff will verify that appropriate models and input parameters have been used to design the erosion protection. The staff will assure t flow rates, flow depths, and shear stresses have been correctly computed.

For the channel side slopes, the staff will verify that the side slopes are capable of resisting flow velocities and shear stresses from flows that occur directly down the s slope. This occurs often when diversion channels are constru':ted perpendicul gullies (which discharge into the diversion channel). Th natural ground slopes in the area are greater than the slope of the diversion channel For the outlet of the diversion channel, the staff will evaluate the design of erosion protection to assure that erosion in the discharge area (normally a natural gully, channel) has been adequately addressed. Designs similar to apron / toe designs will b evaluated to determine thei; resistance to erosion.

For the entire length of the diversion channel, the staff will evoluste the effects of sediment accumulations on flow velocities, ditch capacity, and need for increas or capacity.

h 22 W3

$4 FINAL SRP, NEVISION 1

^ - - - " - -

3 3.3.4.5 Rock Durability 1

l The staff will review the results of durability testing of proposed rock sources to assure that durable rock will be provided. The FSTP provides a detailed method for evaluating rock quality.

3.3.4.6 Construction Considerations The staff will review the plans, specifications, inspection programs, and QA/QC J

programs to assure that adequate measures are being taken to construct the design features according to accepted engineering practices. The staff will compare the i

information provided with typical programs used in the construction industry.

3.3.5 Design of Unprotected Soil Covers and Vegetated Soil Covers if a soil cover is proposed, the staff will evaluate the design using tne general criteria j

outlined in the FSTP. Particular attention will be given to the input parameters to various models.

i (a) The staff will verify that the design flow rate includes an appropriate flow concentrat!.n factor that reflects consideration of settlement, soil removal by sheet i

i flow and wind, degradation of the vegetation cover, intrusion of trees, blockage of I

flows by fallen trees, etc.

f (b) The staff will assure that estimates of Manning's "n" value correspond to the vegetation cover proposed and do not underestimate or overestimate the value to i

determine allowable shear stresses and permissible velocities, respectively, i

(c) The staff will verify that appropriate values of allowable shear stresses and permissible velocities have been used and conservatively reflect potential changes that could occur to the cover over a long period of time as a result of fires, droughts, diseases, j

i vegetation succession, or general cover degradation.

l (d) The staff will check analyses and/or independently calculate allowable slopes using several different methods and ranges of input parameters. Using a range of flow concentration factors, shear stresses, permissible velocities, "n" values, and models, j

the staff will check the sensitivity of the analyses and will verify that reasonable and l

appropriate values of input parameters have been selected.

i l

If a sacrificial soil cover is proposed for ese for the minimum 200-year period, the staff will check the calculations and justification f or reduction of the stability period using procedures given in the FSTP, 4

3.4 Evaluation Findings

If the evaluation by the staff, based upon complete review of hydraulic engineering 1

l

]

aspects of the remedial action plan, confirms that the EPA standards and regulatory i

w 22.1883 1

run se. mvism i 35 d

_ _ _ ~ _ _ _ _ _

i guidelines have been met, documentation of the review will state that:

(1) the flood analyses and investigations adequately characterize the flood potential at the

site, i

f (2) the analyses of hydraulic designs are appropriately documented and employ an acceptable level of conservatism, and j

(3) the general remedial action plan with respect to surface water hydrology and erosion considerations represents a feasible plan for assuring the long term stability provisions of the EPA standards established by 40 CFR 192, Subpart A.

Staff r'e'servations and unresolved technicalissues, based on the review of the surface water hydrology and erosion protection aspects of the proposed remedial action, will be stated in sufficient detail to clearly define the nature of the concerns.

3.5 References American Nuclear Society, American National Sta'1dard for Determining Design Basis Flooding at Power Reactor Sites, ANSl/ANS-2.8,1981.

Chow, V. T., Ooen Channel Hvdraulics, McGraw-Hill Book Co., New York,1959.

i Code of Federal Regulations, Title 40, Protection of Environment, Part 192," Health and Environmental Protection Standards for Uranium Mill Tailings," 1983.

Crippen, J.R. and Bue, C.D., " Maximum Floodflows in the Conterminous United States,"

l USGS Water Supply Paper #1887,1977.

Fread, D.L., "DAMBRK: The NWS Dam-Break Flood Forecasting Model," National Weather Service, Silver Spring, MD, continuously updated.

Henderson, F.M., Onen Channel Flow, MacMillan Co., New York,1971.

Interagency Advisory Committee on Water Data, Hydrology Subcommittee Working Group on PMF Risk Assessment, " Draft Report on the Feasibility of Assigning a Probability to the Probable Maximum Flood," June 1985.

{

Nelson, J.D. gLat., " Design Considerations for Long-Term Stabilization of Uranium Mill Tailings 'mpoundments", NUREG/CR-3397, ORNL-5979, October 1983.

Simons, D.B. and Senturk, F., Cadment Trannoort Technoloov. Water Resources Publications, Fort Collins, Colorado,1977.

Stephenson, D., Rockfill Hvdraulic Ensirrr-iaa Develonments in Geotechnical Enoineerino No. 27, Elsevier Scientific Publishing Company,1979.

2 2.

FesAL SftP, FIEVISION 1 36

9 Temple, D.M.,31a1., " Stability Design of Grass Lined Open Channels," U.S. Department of Agriculture, Agricultural Handbook Number 667,1987.

U. S. Army Corp of Engineers, " Flood Hydrograph Package," HEC-1, Hydrologic Engineering Center, continuously updated.

---" Water Surface Profiles," HEC-2, Hydrologic Engineering Centar, Davis, California, continuously updated.

" Reservoir System Operation for Flood Control," HEC-5, HydrologicEngineering Center, Davis, Califomia.

" Stone Protection," CE 1308, January 1948.

" Standard Project Flood Determinations". EM 1110-2-1411, 26 March 1952 (rev. March 1965).

---" Flood Hydrograph Analysis and Computations," EM 1110-2-1405, August 1959.

" Backwater Curves in River Channels," EM 1110-2-1409, December 1959.

" Routing of Floods through River Channels," EM 1110-2-1408, March 1960.

" Hydraulic Design Criteria," continuously upd'ted and revised.

" Hydraulic Design of Spillways," EM 1110-2-1603, March 1965.

" Interior Drainage of Leveed Urban Areas: Hydrology," EM 1110-2-1410, May 1965.

" Policies and Procedures Pertaining to Determination of Spillway Capacities and Freeboard Allowances for Dams," EC 1110 2-27, February 1968.

" Hydraulic Design of Flood Control Channels," EM 1110-1601, July 1970.

-" Additional Guidance for Riprap Channel Protection,"ETL 1110-2-120, May 1971.

-- Runoff from Snowmelt," EM 1110-2 1406,5 January 1980.

U. S. Bureau of Reclamation, Desian of Small Dams, Second Edition, U.S. Department of the interior,1973.

- Comparison of Estimated Maximum Flood Peaks with Historic Floods," 1986.

U.S. Nuclear Regulatory Commission, Final Staff Technical Position (FSTP) " Design of Erosion Protection Covers for Stabilization of Uranium Mill Tailings Sites," 1990.

---Regulatory Guide 1.59, " Design Basis Floods for Nuclear Power Plants."

= = 22.So n FINAL SRP RiiVISION 1 37

- Staff Technical Position - Standard Format and Content for Documentation of Remedial Action Selection at Title 1 Uranium Mill Tailings Sites", February,1989b.

U.S. Weather Bureau, Hydrometeorological Reports (now U.S. Weather Service, NOAA),

Hydrometeorological Branch: Nos. 43, 49, 55.

l FMAL SMP. MEVtseON 1 38

22.

8

i e

i 4.0 WATER RESOURCES PROTECTION i

1 4.1 Areas of Review The NRC staff has developed a systematic approach for reviewing Remedial Action 1

Plans (RAPS) developed by the U.S. Department of Energy (DOE) for the UMTRCA Title i Uranium Mill Tailings sites. This chapter presents a standard approach for reviewing, l

evaluating, and documenting the technical and regulatory findings for issues pertaining to i

l Water Resources Protection. The ultimate objective of the review is to determine if the proposed remedial action (s) meets the U.S. Environmental Protection Agency (EPA) regulatory standards and is technically achievable. The primary review areas for the Water 4

Resources Protection issues are:

(1) Site characterization of features that affect surface-water and ground-water j

i

movement, i

(2) Conceptual design of the proposed romedial action, (3) Disposal Standards (40 CFR 192, Subpart A; and best engineering practices),

(4) Ground-Water Cleanup (40 CFR 192, Subpart B: and best available technologies), and 1

(5) Supplemental Standards (40 CFR 192, Subpart C).

t Additional discussion of these review areas is provided in SRP Section 4.3.

l i

4.1.1 Site Characterization l

The staff will review regional and site-specific hydrogeologic information related to both the former processing site and the proposed disposal site. The hydrogeologic information should include both surface water and ground-water systems, along with any interrelations among those systems. The processing and disposal sites should be j

adequately characterized for determining the needed level of remedial action and for evaluating the impact the proposed remedial action may have on the water resources.

4 The site characterization review will also include an examination of the assessments that evaluate the existing and potentialimpacts of water contamination. These assessments should provide both quantitative and qualitative estimates of the impact to humans and the environment from any existing and potential groundwater contamination, I

4.1.2 Conceptual Design A detailed description of the proposed remedial action, including a conceptual design of the disposal facility, is an integral part of the water resources review. This aspect of the l

review provides the basis for evaluating whether the proposed remediation will meet the j

ground-water protection standards established by EPA. The conceptual design narrative j

should describe the principal design features that will be relied upon to demonstrate j

j 39

== 22. t **3 riNAt sne, nrvision i j

i i

e i

i a

j compliance with the ground-water protection standards (NRC,1989).

l 4.1.3 Disposal Standards i

The proposed disposal design must assure compliance with the ground water l

j protection standards. Compliance is demonstrated through engineering assessments of the anticipated performance of the critical design features and provisions to demonstrate the post-closure performance of the design through ground-water monitoring. Credible j

failure scenarios and conceptual corrective action plans must also be identified, along with j

a commitment to a detailed Long-Term Surveillance Plan.

1 l

4.1.4 Ground-Water Cleanup i

A clear statement of intent concerning the restoration of ground water contaminated f

by milling operations must be presented in the RAP. The implementation of ground-water cleanup may be deferred to a later project phase, as long as the delay does not impact human health or the environment in the vicinity of the processing site. Detailed j

implementation plans and hydrogeologic characterizations are performed as part of the deferred activities.

4.1.5 Suppler-ental Standards Supplemental ground water protection standards may be used if the processing or disposal sites meet the regulatory criteria for applying supplemental standards as defined in I

l 40 CFR 192.21. These standards may be used in lieu of the standards in Subparts A and B, and may be either numerical or narrative performance objectives. The criterion that j

allows the use of supplemental standards must be identified and the specific standard must be clearly stated in the RAP.

4.2 Acceptance Criteria a

4.2.1 Regulatory Requir'ements i

4 The acceptance criteria that are pertinent to the Water Resources Protection aspects are contained in EPA's regulations under 40 CFR 192. Subparts A, B, and C. The original standards were promulgated with an effective date of March 7,1983 (48 FR 602; January I

5,1983).

1 In 1985, the standards dealing with ground-water requirements were remanded by court action. EPA published proposed new standards on September 24,1987; but to date the standards have not been finalized. Section 108 of UMTRCA requires that DOE comply with the ground-water protection standards proposed by EPA, until such time as the standards are promulgated in final form. Consequently, the remedial action programs are progressing with the published 1987 standards as regulatory guidance. The Commission j

believes that sites where remedial action has been essentially completed prior to EPA's I

promulgation of final ground-water standards will not be impacted by the final ground-water standards. Although additional effort may be appropriate to assess.and remediate 4

i Jua= 22. 5 ***

40 FMAL SMP, REvtBION 1 i

_ - ~ _ _ _

i any existing contaminated ground-water at the processing sites, the existing disposal site designs should be sufficient to provide long-term protection against future grouad-water contamination. Appendix D contains the 1987 ground-water protection standards (EPA, 1987). The EPA standards are divided into three components:

Suboart A - Subpart A contains standards to control further contamination at the disposal sites. The ground water protection standards have provisions to:

(1) Identify a list of hazardous constituents; (2) Determine concentration limits for the identified hazardous constituents; and 1

(3) Determine the compliance point (s) where concentration limits must be met.

In addition to the constituents designated in 5261, Appendix Vill of the Resource Conservation and Recovery Act (RCRA); EPA requires that molybdenum, combined j

radium-226 and -228, combined uranium-234 and -238, and nitrate (as N) be l

characterized at all sites. EPA also designated Maximum Concentration Limits (MCLs) and j

activity limits for these constituents, along with net gross alpha activity.

Not all of the constituents listed in Appendix Vill have MCLs. The comple.s list of constituents which currently have MCLs (Parts 192,261, and 264) are provided in Table 2. None of the 14 organic compounds listed in Table 2, with the exception of 1,2-Dichloroethane, have been identified in uranium mill tailings.

The standards further incorporate provisions for ground-water monitoring to evaluate post-disposal performance of the disposal facility and for the use of alternate concentration limits (ACLs). Additionally, 6192.02(a)(4) requires that the facility closure is performed in such a manner that future maintenance is minimized.

Suboart B - Subpart B contains cleanup standards for the processing site, including ACLs, and passive ground-water restoration. Specific guidance on ACLs for Title I sites has not yet been established by NRC. However, guidance on ACL application at Title 11 facilities is available (NRC Staff Technical Position,1988b). Under the Subpart B standards, the use of ACLs require EPA's approval after NRC determines that the ACLs are as low as reasonably achievable, considering practicable corrective actions. Subpart B also provides for passive restoration allowing ground-water cleanup through natural flushing for an extended period of up to 100 years,if the ground water will not be used as a drinking water source within the remedial period.

Subnart C - Subpart C contains criteria for applying supplemental standards that may be used in place of the requirements of Subparts A and B, under specific circumstances.

6192.21 lists eight conditions (eligibility requirements) that allow the use of supplemental standards.

Supplemental standards may be applied if any one of these conditions pertains to the site. The supplemental standards are qualitative in nature. Consequently, achieving rem sw. mvm i 41 su,. n. iesa

TABLE 2 - Maximum Concentration Limits (MCLs) i i

HAZARDOUS CONSTITUENT MCL (mg/L)

Arsenic O.05 Benum 1.0 Cedmium 0.01 Chromium 0.05 4

Lead 0.05 Mercury 0.002 4

Selenium 0.01 Silver 0.05 Endrin 0.0002 i

( 1,2,3,4,10,1 0-hexachloro-.6,7-epo xy-1,4,4e,5,6,1,8,8 e-oc t ah ydro-1,4-endo, endo-5,8-dimethanonophthalene) i Lindene (1,2,3,4,5.6-hexachlorocyclohexone, gamme isomer) 0.004 Methoxychlor (1,1,1-trichloro-2,2'-bie(p-methoxyphenylethane))

0.1 Toxophone (C.H,oClo, Technical chlorinated camphone, 67 to 69 percent chlonnel O.005 2,4-D (2.4-Dichlorophenoxyecetic acid) 0.1 2.4,5-TP Silvex (2,4,5-Trichlorophenoxypropionic acid) 0.01

, Benzene (Cyclohemetriene) 0.005 Vinyl chlonde (Ethene, chloro-1 0.002 Tetrachloromethene (Carbon tetrechloride) 0.005

)

1,2-Dechloromethene (Ethylene dichlori<te) 0.005 Trichloroethene (Trichloroethylene) 0.005 1,1-Dichloroethylene (Ethene,1,1-dichloro-1 0.007 1,1,1-Trichloroethane (Methyl chloroform) 0.20 p-Okhlorobenzene (Benrene,1.4-dichloro-)

0.075 Nitrete (se N) 10 Molybdenum 0.1 Combined Radium-226 and -228 5 pCi/L Combined Ureruum-234 and -238 30 pCi/L Groes Alpha Particle Activity (excluding redon and urenium) 15 pCL/L F#4AL SMP. REVISlo*4 i 42 Jua 22.***3

i specific numerical values are not necessary to meet the standards, as long as the l

performed actions come as close to meeting the otherwise applicable standards (Cubparts j

A and B) as is reasonable under the circumstances. The proposed actions and the supplemental performance standards must be identified and justified by DOE in the RAP.

l 4.2.2 Regulatory Guidance There are no regulatory guides directly applicable to the Water Resources Protection

]

aspects of the Title i program.

4.3 Review Procedures The NRC staff review of Water Resources Protection assessments is performed for the purpose of providing a technically-defensible, independent verification that the selected remedial actions will meet the EPA ground-water protection standards. The NRC staff review is not meant to duplicate DOE's assessment effort. In performing these reviews, the NRC staff focuses on independently verifying the conclusions and selections made by DOE. The NRC staff verification might include independent literature surveys, data assessments, or calculations. The staff reviewers identify items of concern and convey the issues through w.itten comments or requests for additional information. The stcff primarily focuses on the following areas:

4.3.1 Site Characterization An adequate characterization includes facility, vicinity, and hydrogeologic information.

The reviewer should ensure that these components are described in terms of both the surface-water and ground-water systems at the processing and disposal sites.

4.3.1.1 Facility Characterization An adequate facility characterization is needed to evaluate the existing and potential contamination at the processing site. This characterization provides information on human activities that may have impacted the mill site. General descriptions of the facility might be presented in the executive summary or introductory sections of the RAP. The reviewer

)

should ensure that the general descriptions provide adequate detail for evaluation of the water resources protection assessments. A facility characterization is acceptable if it includes:

l i

(1) The description of the uranium recovery process (es) and the duration of use, (2) A description of reagents and the relative quantities used in the milling process, and (3) A description of waste management practices, such as: types of wastes generated, waste discharge locations, retaining structures for wastes, relative waste quantities, and chronology of waste management practices.

The reviewer will also determine whether the level of detail provided in the facility FINAL SAP, MVISION 1 43 June 22. t oss

l characterization is proportional to the amount of information required for an adequate contaminant-source characterization. The expected impacts of the described operational practices on the hydrogeologic system, and background water quality should also be considered during the facility characterization review.

4.3.1.2 Vicinity Characterization At some sites, human activities unrelated to the milling operation and natural processes may have altered the hydrogeologic system. Such activities may influence the selection of remedial actions. Human activities include: ground water use, crop irrigation, mine dewatering, ore storage, municipal-weste landfills, oil and gas development, and exploratory drilling. Natural processes include: geothermal springs, natural concentration of soluble salts by evaporation, and ground water / surface-water interactions.

The r? viewer will determine whether these factors have been appropriately considered in the remedial action selection. An acceptable vicinity characterization adequately identifies and evaluates the magnitude of the effects of vicinity activities and processes on the selection of remedial actions.

4.3.1.3 Hydrogeologic Characterization The hydrogeologic characterization is the primary site characterization component that is used to evaluate whether the proposed remedial actions will comply with the EPA ground water protection standards. The hydrogeologic characterization relies on comparisons of the base-line conditions to the milling operation influences. The characterization also encompasses the anticipated impacts that any existing contamination may have on present and future human and environmental populations. The primary elements of the hydrogeologic characterization include:

(1) Identification of hydrogeologic units, (2) Identification and assessment of the hydraulic and transport properties, (3) Description and measurement of the geochemical conditions and the contamination extent, and (4) Assessment of the current and future water uses, i

The reviewer should be sensitive to the overall quality and defensibility of DOE's field investigations. There may be instances where DOE will use data or take measurements from other projects, which were not conducted by DOE, and may not have the same level of quality control as the UMTRA Project investigations. The reviewer should identify any data presented in the RAP that were not developed by DOE and what design or characterization conclusions are influenced by those data. The reviewer should confirm that DOE has provided written assurance that any 'non-DOE data' used in the RAP are at least of an equivalent quality-level as data that DOE would have developed. Examples of the data types that may be included in this category are:

u. 22. ton re n se. mvisxm i 44

t l

Existing monitoring well data from previous investigations, e

i l

e Historical analytical data, or Aquifer property measurements, both field and laboratory derived.

e There may be other types of data presented in the RAP that were not developed by l

DOE during the course of the UMTRA Project. The reviewer should identify these data as apart of the RAP review.

i 4.3.1.3.1 Identification of Hydrogeologic Units 1

?

The reviewer should verify that adequate hydrogeologic information is provided for l

review (NRC,1989). This information includes; the geometry, lateral extent, and thickness of all potentially affected aquifers and confining units at the processing and

}

disposal sites. This information will normally be provided as hydrostratigraphic cross-sections and outcrop maps. The reviewer should ensure that the data quality and quantity t

are adequate to support a technically-defensible interpretation.

i The reviewer should also verify that DOE has provided sufficient descriptions of the unsaturated units that may convey hazardous constituents to the water-bearing units.

Adequate information should be provided to support a representative conceptual model for contaminant transport pathways. This would include identifying potential preferential flow i

pathways that are both natural and man-msde.

The identification of hydrogsologic units is important in determining where (i.e., the uppermost aquifer) regulatory compliance will be met. As an example, the NRC staff has i

had questions in several reviews (Belfield/ Bowman and Rifle sites) as to whether specific units were identified as aquitards or aquifers. This specific concern had a direct bearing on the depth that post closure compliance monitoring would be performed, and whether the monitoring would be appropriate for verifying cell performance.

Adequate characterization information should also be provided for the processing site, if the RAP proposes to relocate the tailings from the processing site to a new disposal site.

Characterization at the processing site,in these cases,is used to evaluate any proposal to defer the ground-water restoration to a later project phase. The level of characterization necessary to support the deferral of ground-water restoration is likely to be less rigorous than the characterization needed to develop and implement a restoration program. The characterization should be sufficient to support the conclusion that human and envirorsmental populations will not be substantially impacted if the ground-water restoration is delayed to a later project phase.

The NRC reviewer should nct assume that the hydrostratigraphic description provided in the Geology report of the RAP corresponds closely with the description in the Ground-Water Hydrology report. Since these reports are often prepared by different staff within the DOE's Technical Assistance Contractor (TAC), and emphasize different characterization concerns; there are often differences between the two reports that may become important when identifying potential preferential flow zones.

m asae,nrvem1 45 h = 22. m3

l i

i

=

1 As appropriate, the reviewer should determine that the following information has been

~

inciuded in the identification of the hydrogeologic units:

Maps of sufficient detail that show the dimensions and locations of hydrogeologic e

systems that could have been' impacted by milling operations:

Descriptions and measurements of any interactions among the various components l

e of the hydrogeologic system, such as, surface-water and ground-water l

relationships Climatic characteristics, including precipitation, potential evapotranspiration, and l

e temperature; Geologic characteristics, including local and regional structures, fractures and joints,

}

e lithologic and stratigraphic distributions, and solution porosity (refer to Chapter 1.0 j

- Geology and Seismology); and 1

l e Surfacs-water characteristics including location, flow rates, drainage areas, seasonal variations, hydrographic modifications, and current water allocations (refer to Chapter 3.0 - Surface Water Hydrology and Erosion Protection).

The review of the properties that affect ground-water flow and coritaminant transport are performed under separate review categories, as described below.

4.3.1.3.2 Hydraulic and Transport Properties The reviewer should verify that DOE has adequately described the hydraulic and transport properties of potentially affected hydrogeologic units at both the processing and disposal sites (NRC,1989). Hydrogeologic parameters that should be provided in the RAP include: hydraulic conductivities (K,, and K,), gradient, effective porosity, solution porosity, storage coefficient, and dispersivity. The reviewer.must determine which of these parameters exerts the greatest influence on compliance with the standards. The reviewer should confirm that the critical parameters have been measured at the site during DOE's characterization efforts. The exception to this is the effective oorosity, which can be conservatively estimated, based on lithology and measured grain-size distributions.

Normally, an effective porosity of 10 percent is assumed conservative (represents the largest flow velocity), unless measured grain size and compaction information support a different value.

The reviewer should examine the methods, procedures and calculations that DOE used to obtain these parameters. For example, the hydrologist should review DOE's aquifer testing field procedures and calculations to confirm that the proper field and data-analysis techniques were used to develop the hydraulic conductivity measurements. If DOE proposes to use mean hydraulic parameters in their analyses, the reviewer should consider that many hydrogeologic parameters, including hydraulic conductivity, typically exhibit a log-normal distribution. Consequently, the geometric mean may be more representative of the overall conditions within a unit than the arithmetic mean.

FWAL SRP. MEVSWE 1 46 Am 22.1993

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The reviewer should also verify that literature values selected for effective porosity conform to the measured porosities of the various geologic materials. As a coarse check, the measured total porosity (inverse of the geotechnical void ratio) will generally be greater than effective porosity, because the dead end pores do not contribute to ficid flow. Also, the specific yield measured during pumping tests of unconfined aquifers will be roughly equivalent to the effective porosity of the aquifer medium.

The storage coefficient is usually not a critical parameter unless transient analyses are performed. Generally, most of DOE's analyres assume steady state ground-water flow conditions given the long time periods represented by the analyses. Dispersivities are also not generally critical, unless a contaminant transport analysis is used to demonstrate compliance. Dispersivity is difficult to quantify at the field scale, consequently literature values are often used. The reviewer should evaluate the literature dispersivity values, and verify that they represent conservative estimates.

Discussions of the various hydrogeologic parameters, including ranges for various geologic materials, can be found in Todd (1980); Bear (1979); Freeze and Cherry (1979);

Lohman (1972); and Walton (1970).

An acceptable ground-water flow characterization should consider the aquifer properties and geologic features that affect the rate and direction of ground-water advection. The characterization of transport mechanisms should include contaminant dispersion properties and aquifer attenuation f actors.

4.3.1.3.3 Geochemical Conditions and Contamination Extent l

Details on the geochemical conditions that could affect the attenuation of hazardous i

constituents is an essential part of the submitted information (NRC,1989). In general, this information will not be needed at a separate processing site until DOE proposes to address the Subpart B standards.

The reviewer must ensure that information on the geochemical conditions at the disposal site is provided, to support the conclusion that the standards will be met. The primary geochemical inf ormation includes:

The chemical composition of the tailings leachate, e

The chemical and mineralogical composition of the subsurf ace materials, and e

The background ground water quality.

e The chemical composition of the teachate is readily measured from tailings pore-water samples. The chemical and mineralogical composition of the underlying lithologies are characterized by measurements of pH, buffering capacity, redox potential, adsorptive capacity, cation exchange capacity, and identification of the clay mineralogy. The gene chemical characteristics of fluids within the lithologies can be described by measurements of pH, temperature, specific conductivity, redox potential, and buffering capacity.

w 22. m 2 47 rma sw. mvsm i

1 1

i Teilings leacht le will generally be oxidized and either highly acidic or highly alkaline, j

depending on the milling process. Geochemical precipitation will cause some radionuclides, heavy metals, and some major ions to become relatively immobile. DOE generally takes credit for attenuation as an additional level of conservatism when the f

ground-water protection standards are met through some other mechanism. The I

attenuation capability for these cases is usually supported by laboratory analyses of j

organic content and bulk clay mineralogy, field measurements of redox and pH, and valences of the hazardous constituents.

i

(

l Batch column-equilibria measurements, using representative leachate and soil samples, also must be performed in cases where the geochemical attenuation is the primary I

mechanism for achieving compliance with the standards. The reviewer should determine that DOE has demonstrated that adequate attenuation material is available at the disposal i

site to meet the design-life criteria of the disposal cell. DOE also should provide an assessment of the likelihood of permeability reduction in the attenuating medium, due to i

the additional mineral precipitation, and any adverse impacts on other design components

{

of the disposal cell. Additionally, DOE should acdress the likelihood of hazardous constituents disorbing from the attenuation medis under changes in redox conditions.

1 The extent of existing ground-water contamination must be determined at the i

l processing site, even ir DOE proposes to defer ground-water cleanup. An adequate i

characterization of the background ground-water quality is fundamental to the assessment l

of the existing ground-water contamination. Background water quality is defined as the chemical quality of water that would be expected at a site if contamination had not j

occurred from the uranium milling operation. Ambient contamination from uranium ore l

bodies, mining operations, or other human activities are considered as part of the

]

background water quality.

DOE usually provides a statistical comparison between the on-site, down-gradient j

ground-water quality; and background ground-water quality to determine the i

contamination extent. The statistical me.. odology normally employed is an EPA l

methodology (EPA,1989b). The reviewer must confirm that DOE has demonstrated that l

public health and the environment will not be substantially affected by deferring the ground-water cleanup. The effort expended to determine the background water quality should be proportional with the anticipated impacts any potential contamination may have on human health and the environment. The reviewer should determine that the l

background water-quality determination includes the following types of information, as l

applicable:

a Maps of sufficient detail and legibility showing the background monitoring locations;

]

e

\\

Descriptions of background monitoring devices including wells, springs, community i

water supplies, suction samplers, or other sampling devices; The distribution of wastes and contaminated materials at and near the site; j

e i

Description of historical changes in hydraulic heads, flow directions, and flow rates j

)

e i

relevant to the monitoring locations; 1

i FINAL SMP, REVite0*f 1 48 Jwn 22, m3 i

.. ~ - - - -.

i Laboratory water quality data for hazardous constituents major ions and indicator e

parameters; Assessments of any observed variations in background water quality; e

identification of any off site sources of water contamination; and e

Quality control / quality assurance procedures associated with the background water e

quality measurements: such as sampling protocols, laboratory analytical methods, i

field measurements, sample handling procedures, and quality assurance documentation.

l An acceptable characterization of the contamination extent should include the spatial distributions of contaminants in ground water and surface water that exceed background or MCL concentrations of the hazardous constituents or indicator parameters. The contaminant distribution described in the characterization should be based on an adequate number of sampling locations and sampling episodes to technically support DOE's i

I interpretation. The reviewer should determine that the characterization includes:

The distribution and characteristics of on-site wastes; such as wind-blown e

contaminated materials, tailings piles, raffinate ponds. evaporation ponds, ore storage areas, and rubbish heaps:

identification of constituents that are measured at concentrations above the e

background levels and are reasonably expected to occur at the processing site:

i Constituent concentrations and indicator parameter values, including: pH, Specific e

Conductance, major ions, minor ions, trace metals, nitrate, uranium-234 and

-238, radium-226 and -228, and thorium-230; j

A comparison, statistical or graphical, of the contaminated water quality to the e

background water quality; Maps and cross-sections showing the oistribution of constituent concentrations in e

the ground water; and Quality assurance validation of the collected analytical data by replicate analyses, e

and ionic charge balances to within 5 percent of the total dissolved solids concentration.

Determining the contamination extent is required when DOE proposes on-site disposal, and also when DOE proposes to defer ground-water cleanup. DOE must clearly demonstrate that the on-site disposal will not interfere with future cleanup activities. The reviewer should consider the following technical elements when verifying whether DOE has adequately characterized existing ground-water contamination:

(1) Adequacy of the number of wells to represent background, on-site, and down-gradient conditions:

An. 22. ises 49 FINAL SAP, MEVISION 1

(2) Suitability of the background welllocations; (3) Appropriateness of screened intervals and completion depths for wells; and (4) Appropriateness of the constituents (hazardous and indicator) included in the analyses.

When ground-water cleanup is deferred, the complete determination of the vertical and lateral ground-water contamination extent is not the main concern of the review; unless human health or anvironmental populations could be affected by the contamination. It is expected that the existing plume will continue to migrate until cleanup is initiated. The reviewer should also verify that DOE has made provisions to continue monitoring the plume until restoration has been initiated.

4.3.1.3.4 Water Use The reviewer should verify that information on existing and projected water uses near the processing and disposal sites has been provided (NRC,1989). The information should include a description of the hydrologic zones or locations where the water is being extracted, a description of the use, and water quality information. Generally, this information is provided for the area within a 1.6-3.2 kilometer (km) (1-2 mile (mi)) radius of the site.

The reviewer must assure that DOE has demonstrated that the surrounding water users will not be adversely affected by deferral of ground-water cleanup. In some cases, DOE indicates that the site is hydraulically isolated from nearby water users. In these cases, it is only necessary that DOE adequately demonstrate that the site is isolated and that there are no water users within the boundaries of the isolated area.

t Human water consumption is not the only water use considered in the review. Any use that may bring someone into contact with the contaminated water must be considered when evaluating health hazards. For exan.ple, contaminated ground water containing redon, which is only used in the rest rooms of a building, could still pose a substantial health hazard.

Many of the Title I processing sites are located near rivers, since the uranium milling process typically requires a large amount of water. There commonly is a hydraulic relationship between the surface water and the shallow ground-water systems at those sites located within the river floodplain. Over some portion of the year, the river will serve as a discharge location for the shallow ground-water system. Typically DOE provides water-quality data up-stream and down-stream of the site to quantify any water quality impacts.

The reviewer should assess whether the information demonstrates that contaminants entering the river will be diluted to below the appropriate concentration limits, even during low flow conditions. DOE must provide information in the RAP that quantifies the impacts to down-stream users, including recreational uses.

FMAL SMP. ENSON 1 50

.aw. 22. im

. _ =

1 a

l 4.3.2 Conceptual Design Features I

The reviewer should confirm that DOE has described the principal design features of j

the proposed remedial action that are relied upon to demonstrate compliance with the i

water resources protection aspects of the standards (NRC,1989).

J l

DOE willlikely propose one of the following disposal options for the remedial action at 1

a mill site:

}

(1) Tailings and contaminated materials are stabilized in place at the processing site (SIP);

(2) Tailings and contaminated materials are stabilized on site (SOS), but moved to a 1

different location on the processing site property; or i

(3) Tailings and contaminated materials are relocated to a different property and stabilized.

The selection of the disposal method that will meet the EPA standards (DOE,1989a) is based upon technical and cost considerations. Figure 1 shows a schematic cross section of the typical disposal cell design that DOE might use.

As Figure i shows, DOE typically employs a multi-component cover design, which consists exclusively of natural materials. The cover is the most important design element for demonstrating compliance with the ground-water protection standards. Cover designs will vary from site to site: however, the following components will have the greatest impact for Water Resources Protection:

l e The radon / infiltration barrier; 1

l e The drain layer (s); and f

Vegetation (if applicable).

The amount of water that will come in contact with the contaminated materials will be l

the main factor that determmes the amount of leachate generation; and, consequently, j

whether the ground-water standards will be met. Some determination of the leachate-generation potential is needed, s;nce it is reasonable to expect that some meteoric water j

will enter the tailings. The radon / infiltration barrier is the most important cover component for demonstrating compliance with the ground water protection standards, because it is j

designed to limit the amount of water that enters the tailings.

l The redon/ infiltration barrier is usually constructed from compacted clays. There may be some instances where a sodium bentonite additive is used to further reduce the i

{

hydraulic conductivity of the barrier. Synthetic liners have not been used, because their long-term reliability has not been demonstrated (Caldwell et. al.,1988).

Both the drain layer and vegetation will usually keep water away from the radon barrier. These components usually provide an added level of confidence that the standards d

i rinat sne. nevision i 51 J== 2 2 ' " 5 j

l

i l

FIGURE 1 - Schematic of a Typical UMTRA Cover i

I I

i Top Cover Detail t

j

__ Vegetation / Riprap i

l l

1 l

}

l i

COVER 1

s

= 2 2 ' " 8 52 raatsne.nEVt500N i

will be met. Consequently, a separate compliance demonstration for these individual j

components is not generally performed. These components are primarily designed to l

perform a function other than limiting infiltration.

i l

The drain layer normally consists of coarse sand with a large horizontal hydraulic conductivity. This layer is normally placed above the radon barrier to provide lateral I

drainage off the barrier. Ideally, this layer will aid in keeping the barrier from becoming j

fully saturated. The drain layer is also used to protect the redon barrier from freere/ thaw I

stresses. The cover vegetation (note: DOE does not commonly include vegetation on the side-slopes), helps to remove moisture by evapotranspiration. A vegetation cover is not l

proposed for all sites, due to climate considerations. When a vegetation layer is proposed, l

the primary function is for erosion protection, and limiting infiltration is an added benefit.

J Additional discussions on the cell cover components are presented in Chapter 2.0 l

GEOTECHNICAL STABILITY, and Chapter 3.0 SURFACE WATER HYDROLOGY AND i

EROSION PROTECTION.

i The reviewer will generally not be concerned about the design features of the drainage layers and vegetation, since these components are typically not relied on to demonstrate j

compliance with the standards. DOE typically employs one of the following approaches to demonstrate that the radon barrier will contribute to the cell's compliance with the ground-l water standards:

i An engineering analysis to show that fluid flux through the cover, equal to the e

design saturated hydraulic conductivity, vill allow compliance with the standards; An engineering analysis to show that fluid flux through the cover, using the e

unsaturated hydraulic conductivity of the cover, will allow compliance with the standards; or e A demonstration that shows that the standards can be achieved without limiting infiltration through the cover.

DOE commonly uses a simple volumetric mixing calculation as described in Hem (1985) to demonstrate that the standards will be met when a fluid flux equals the saturated hydraulic conductivity of the barrier. The results of this calculation should show that concentration limits will be met at the point of compliance. The assumption is made that the infiltration barrier has become fully saturated; therefore, only gravity drainage is occurring and the hydraulic gradient is one. Such an assumption is more conservatWe than assuming partial saturation, since the saturated hydraulic conductivity exceeds the unsaturated hydraulic conductivity.

The larger fluid flux used in this approach makes the compliance demonstration more difficult. As a consequence, DOE will usually include the lowest possible saturated hydraulic conductivity in the design of the radon barrier. The NRC staff has raised concerns on whether a saturated hydraulic conductivity of less than 1 x 1C cm/s can be constructed and adequately verified by field-scale measurements. The technicalliterature suggests that laboratory measurements of saturated hydraulic conductivity may not be representative of the field conditions. The Water Resources and Geotechnical reviewers FINAL $RP. REVISION 1 53 u. ar. sees

should jointly evaluate whether DOE has provided adequate information to demonstrate f

compliance. Bennett and Horz (1991) provides a good discussion on laboratory-versus field-measured hydraulic conductivity values for covers. Additional discussions on the cover hydraulic conductivity are preseni6d in Section 2.3.5.

DOE may also use an assumed fluid flux that is based on the unsaturated hydraulic j

conductivity of the barrier. Because the unsaturated conductivity is less than the I

saturated conductivity, the compliance demonstration may be easier to make. In this situation, DOE must demonstrate that the barrier will remain unsaturated throughout the design life of the cell..This demonstration is often difficult, considering the design life of the cell. DOE has previously attempted to use the results from a study for the Shiprock site, which indicated that the cover remains fairly unsaturated (DOE,1989b), as a demonstration that the cover will remain unsaturated at other sites. The NRC staff has rejected this argument, because of some identified problems with the Shiprock test (Jones, 1989). The reviewer will have to rely on professional judgement to verify that DOE's demonstration, provided in the RAP, will adequately confirm that the cover will remain unsaturated.

The reviewer must ensure that DOE provides a clear and defensible compliance demonstration, if the proposed design does not rely on limiting infiltration in order to meet the standards, in these instances, the demonstration is usually based on.

e Climatic considerations, Hydraulic isolation of the uppermost aquifer, e

Geochemical properties in the underlying materials, or e

Meeting the criteria of $192.21 and proposing a supplemental standard for e

compliance.

4.3.3 Disposal Standards The reviewer will verify, based on DOE's de;nonstrations, that the proposed design complies with EPA's ground water protectiori standards in 40 CFR Part 192, Subparts A and C. DOE's demonstrations should include: (1) the ground-water protection standards, (2) a performance assessment, (3) a closure performance demonstration, and (4) a performance monitoring and corrective action program (NRC,1989),

4.3.3.1 Ground-Water Protection Standards The reviewer must confirm that DOE has proposed a ground-water protection standard for the disposal site (NRC,1989). This standard must include: (1) a list of hazardous constituents, (2) a corresponding list of constituent concentration limits, and (3) a point of compliance.

= 2 2. i m rum se. mvmo** 1 54

i i

4.3.3.1.1 Hazardous Constituents

(

l The EPA has proposed a list of 375 hazardous constituents which must be considered i

by DOE. Additionally; molybdenum, nitrate, radium, not gross alpha and uranium must be l

also considered by DOE when developing a list of hazardous constituents.

The NRC uses the following criteria to determine the adequacy of the hazardous i

constituents list:

q l

(1) The constituents are reasonably expected to be in or derived from the tailings;

.I (2) The constituents are listed in Appendix Vill of 40 CFR 5261; with the addition of molybdenum, not gross alpha, nitrate, radium, and uranium (Table A,40 CFR 5192);

and (3) The constituents were detected in the tailings or ground water at the processing site.

j Some understanding of the milling process used at the particular site is required to determine whether the constituents are reasonably expected in the tailings. A typical milling process involved crushing and grinding the uranium ore, dissolving it in either an acid or base solution, then concentrating and purifying the uranium with either an ion exchange or a solvent extraction (Merritt,1971). The constituents are mobilized by leaching the crushed ore with either an acid or base. Sulfuric acid or sodium carbonate are typically used. Acid-extraction was used at most mills, because it is generally more effective than alkaline teach except for ores with a high carbonate content.

The leaching, concentrating, and purifying processes make the largest contribution to the hazardous constituents found in the tailings and ground water. The reviewer should verify that adequate information on the process is provided in the RAP. Table 3 provides a list of the common constituents associated with uranium tailings (NRC,1987). This list is based upon a chemical survey performed by NRC staff at 17 Title 11 sites. This list is not all inclusive, since the milling process used may have contributed additional hazardous constituents.

DOE normally performs an initial scan of either pore fluids from the tailings or ground water from several existing wells to determine potential hazardous constituents for a particular site. Additional sampling is conducted to determine which specific organic compounds are present. The expected presence of organic compounds can be determined, based on the knowledge of the chemicals used during the milling process. Even if there is no record of organic compounds used in the process, screening tests should be performed to confirm the absence of organic compounds in the tailings and ground water.

DOE has developed a standard constituent list for inorganic screening of tailings fluid or ground-water samples. Table 4 lists these constituents (DOE,1989a). Each of the Table 4 constituents are included in the list of potential hazardous constituents, if they are i

idantified above the detection limit. A comparison of Table 4 to Appendix Villindicates that nct all of the constituents in Table 4 are considered hazardous. Consequently, only those constnuents (or elements of hazardous compounds) that exceed the method FiMAL SAP. REVISION 1 55

== 22.1 *e3

1 TABLE 3 - Common Chemical Mill Constituents INORG ANIC CONSTITUENTS Arsenic Barium Beryllium Cadmium Chromium Cyanide Lead Mercury Molybdenum Net Gross Alpha Nickel Radium-226 and -228 Selenium Silver Thorium-230 Uranium ORGANIC CONSTITUENTS Carbon disulfide Chloroform Diethyl phthalate 2-Butanone 1,2-Dichloroethane Naphthalene Jua= 2 2.1 **

56 FMAL SMP, REvtse0N 1

j TABLE 4 - Constituents / Detection Limits for Watcr An lysss' DETECTION DETECTION CONSTITUENT LIMIT CONSTsTUENT LIMIT I

Major Anions (mg/L)

Copper 0.02 I

Bicarbonate 1.0 Cyanide 0.01 Carbonate 1.0 Iron 0.03 l

Chloride 1.0 Lead 0.01 Sulfate 0.1 Manganese 0.01

]

l Fluoride 0.1 Mercury 0.0002 Nitrate 1.0 Molybdenum 0.01 1

Nitrite 0.1 Nickel O.04 Nitrate and Nitrite 1.0 Selenium 0.005 i

j l

Phosphate (as P) 0.1 Silver 0.01 Sulfide (as H S) 0.1 Major Cations (mg/L) 2 Ammonium 0.1 Strontium 0.1 Calcium 0.01 Thallium 0.01 l

Magnesium 0.001 Tin 0.005 l

Potassium 0.01 Uranium 0.003 4

Sodium 0.002 Vanadium 0.01 l

Silica 2.0 Zinc O.005 Tot. Dissolved Solids 10.0 l

Minor and Trace" (mg/L) l Aluminum

0.1 Organk

Hazardous *

(mg/L)

Antimony 0.003 Tot. Organic Carbon 1.0 i

Arsenic O.01 Radionuclides (pCi/L)

Barium 0.1 Gross alpha 1.0 d

Beryllium 0.01 Gross beta 0.5 d

Boron 0.01 Lead-210 1.5 Bromide 0.01 Polonium-210 1.0 l

l Cadmium 0.001 Radium-226 1.0 Chromium 0.01 Radium-228 1.0 Cobalt 0.05 Thorium-230 1.0

Field parameters meluding temperature, total elkelinity, pH. and specific conductance will be measured.

Dissolved oxygen. Eh. and redox couples may be measured at specific work estes for further chorectorization.

j

Elemental concentrations will be snelyzed to metisfy the requirements of 40 CFR 192.

l

Appendix IX of 4o CFR 264 will be enelyzed to setiety the requirements of organic enelysee required in Appendix I of 40 CFR 192.

f

These snelyses must be determined on semples with less then 500 mg/L total dissolved solide.

Note: Detection limite above are those specified to laboratones subcontracted to perform analysee for the j

UMTRA Project. These levele are considered reasonably achievable, and consisten* with Project enais and i

regulatory requiremente.

i l

l June 22.1993 57 f1NAL SMP. REVi$lON 1 1

M d

I detection limit, and are listed in Appendix Vill (40 CFR 6261) or Table A (40 CFR 6192);

should be included in DOE's hazardous constituent list.

l The elements of a hazardous compound should also be listed,if the combination of those elements detected in the tailings pore fluid would produce a hazardous compound under the right geochemical conditions in the subsurface. For example, if strontium and su! fide ions have been detected b the tailings pore fluid, and the geochemical conditions in l'

the uppermost aquifer favor the precipitation of strontium sulfide (listed in Appendix Vill);

then strontium and sulfide should be included at a hazardous constituent. However, if j

aluminum ions are detected and no corresponding anions would produce a hazardous compound under the subsurface geochemical conditions; then aluminum should not be listed as a hazardous constituent.

DOE commonly uses suction fysimeters to obtain pore fluid samples from the tailings.

A lack of moisture within the tailings may preclude the collection of pore-water samples in 4

l this manner. In these cases, DOE will collect ground-water samples and infer the concentrations within the pore fluid. The reviewer should be aware that the projected concentration within the pore fluid should be righer than the measured ground water concentration, because of the dilution. The identification of a hazardous constituent in the 2

ground water should provide a fairly accurate representation of the more mobile compounds in the tailin.as.

\\

l 4.3.3.1.2 Concentration Limits i

A concentration limit must be specified for each of the hazardous constituents i

identified by DOE. The concentration limit must be either the Maximum Concentration l

Limit (MCL) as identified in Table 4.1, the background concentration, or an Alternate Concentration Limit (ACL). The reviewer should verify that DOE has provided a

)

justification for its selection.

DOE typically proposes either the background level or the MCL's, whichever is greater.

Many of the hazardous constituents, including some of the commonly detected constituents listed in Table 4.2, do not have an established MCL. Therefore, background levels or ACL's must be used in establishing the concentration limit.

The reviewer should ensure that the background concentrations accurately represent the ambient conditions that are unaffected by the milling operation. Ground-water samples collected from walls used to select a disposal site, where the processing and j

disposal sitas are separate, are good representations of background levels since contaminants have not yet been placed on the site. However, the background levels must j

be clearly representative of non-milling conditions for sites where SIP or SOS disposal is proposed. Background samples should be collected from wells that are clearly unaffected by the contamination source, preferably hydraulically up-gradient of the milling site. A l

rigorous justification should be provided in the RAP if the wells used to establish background are not hydraulically up-gradient from the contamination source.

I DOE will commonly use the statistical maximum concentration of the constituent as the proposed concentration limit. This is done to account for natural, variations in water mn sne. nevam i 58 h 22. m 3

quality. The reviewer should verify the correct statistical method was used to establish the statistical maximum. DOE may propose the maximum measured concentratic.) or the method detection limit as the concentration limit, if a statistical maximum cannot be determined.

4.3.3.1.3 Point of Compliance i

The reviewer should confirm that the point of compliance (POC) for the disposal site has been proposed in the RAP (NRC,1989). The POC is the location where the ground water can be monitored to determine compliance with the proposed concentration limits.

The POC is defined as a vertical surface within the uppermost aquifer at the hydraulically down-gradient limit of the waste management area.

The NRC has generally interpreted the down-gradient limit of the waste management area to be the edge of the cover side slopes. It is not recommended that DOE be required to compromise the cover integrity in order to install monitoring wells at the actual edge of the reclaimed tailings.

DOE will generally propose to install a line of wells along the down-gradient edge of the cell to monitor the POC. The reviewer should verify that:

The proposed monitoring welllocations are hydraulically down-gradient from the e

cell, The proposed well spacings will adequately monitor the dominant flow pathways in e

the uppermost aquifer, and Screened intervals in the wells located in the uppermost aquifer will be able to

]

detect potential contaminant releases.

Construction details for new POC monitoring wells are usually provided in the Long-Term Surveillance Plan (LTSP).

4.3.3.2 Performance Assessment The reviews: should verify that DOE's assessment of disposal cell performance complies with the ground-water protection standards for disposal, listed in 40 CFR 6192, i

Subparts A and C (NRC,1989). This assessment should demonstrate that the identified hazardous constituents will not exceed the proposed concentration limits at the POC during the design life of the disposal cell.

J DOE has employed a wide range of methods to assess the performance of the disposal unit. These methods range from qualitative narratives with supplemental standards to quantitative analyses using contaminant transport models. Regardless of the method, the reviewer should confirm that the information presented in the RAP is of adequate quality and quantity to support a defensible assessment. The characterization detail will be dependent on the type analysis used to demonstrate compliance.

FINAL SAP. REVISION 1 59

== 22. t es 3

The reviewer should not assume that simple, quantitative analyses are necessarily conservative. The reviewer should not attempt to duplicate DOE's analyses, especially for complicated transport models. The reviewer's resources can be more prudently applied by evaluating:

The validity of the assumptions used to develop the conceptual model that e

represents the hydrogeologic system, and the limitations imposed by those assumptions; The technical appropriateness of the analysis methods used under the constraints e

of the conceptual model; and The adequacy (quality and quantity) of the data used.

e Duplication of analyses may be appropriate, if the reviewer is concerned whether DOE's analysis is technically defensible.

4.3.3.3 Closure Performance Dr monstration s

The reviewer should verify that the anticipated closure performance will comply with 1

the standard in 1192.02(a)(4), which references the RCRA closure performance standard in 1264.111 (NRC,1989). The demonstration should show that:

(1) The need for long-term maintenance of the disposal site has been minimized; and (2) The disposal unit controls, minimizes, or eliminates releases of hazardous constituents to the ground water; to the extent necessary to comply with the ground-water i

protection standards.

Generally, DOE's compliance demonst ation in the performance assessment will also adequately demonstrate that the disposal unit will control, minimize, and eliminate releases of hazardous constituents and comply with the ground-water standards. The use of adequate amounts of stable, natural materials in all components of the cover will generally demonstrate that long-term maintenance of the facility will be minimal.

The water resources protection reviewer should be aware that there are some aspects of the engineering design that may have been proposed to comply with one review area, but may compromise compliance in another area. One example is the concern of moisture retention, redistribution, and accumulation that may result from the bottom of the cell having a hydraulic conductivity that is lower than the designed infiltration flux of the cover. This situation is often referred to as a ' bath tub' effect. Although the designed redon barrier may meet the radon emission requirements, and the low hydraulic conductivity of the subgrade will comply with the provisions of eliminating releases of hazardous constituents; the potential water accumulation may cause a saturated condition in the disposal cell that could impact the long-term geotechnical stability of the contaminated materials.

FINAL SRP. MVISION 1 60 h w H,1993

3

.i i

i As another example involving a ' bath tub' effect, water addad to the tailings for j

achieving the compaction specification and for dust suppression may redistribute by unsaturated-flow mechanisms and accumulate at the base of the disposal cell, causing the potential for short term geotechnical instability. The reviewer should convey any concerns

)

that may impact other technical areas to the appropriate NRC staff reviewers.

t 4.3.3.4 Ground-Water Monitoring and Corrective Action Plan The reviewer should verify that a conceptual ground-water monitoring and corrective action program are described in the RAP (NRC,1989). The EPA regulations (40 CFR Part 192.02(b)-(c)) require that DOE establish a post-disposal monitoring program to ensure that the ground-water protection standards are met, and a plan of corrective action in the event that contaminants are detected after closure has been completed. Any corrective action would have to be implemented within 18 months of a determination that ground-water concentration limits are, or will be exceeded.

DOE is only required to provide a general conception of the monitoring and correction action programs in the RAP, since the detailed aspects will be provided in the LTSP, which also requires the NRC concurrence. The reviewer should ensure that most of the realistic failure scenarios are identified and addressed by conceptual corrective action plans; and confirm that DOE states their intent to provide the detailed ground-water monitoring plans in the LTSP.

4.3.4 Ground-Water Cleanup Restoration of contaminated ground water at the processing site can be postponed i

(deferred) if:

(1) The disposal activities proposed in the RAP will not interfere with future cleanup activities:

(2) The disposal activities can proceed independently of ground-water cleanup; and (3) Public health and safety will not be affected by delaying ground-water restoration.

DOE has adopted a policy of deferring ground-water cleanup to a later phase of the UMTRA Project. Conceptual designs and descriptions of the restoration programs will be developed in a later project phase. The NRC has agreed with delaying restoration, as long j

as human-health and the environment will not be substantially affected, as verified by ground-water monitoring. The reviewer should confirm that the surrounding water users will not be adversely affected by delaying restoration (subsection 4.3.1.3.4 of this chapter).

If DOE chooses to initiate a ground-water cleanup, the reviewer must verify that the proposed ground-water cleanup actions will comply with EPA's ground-water protection standards. DOE's plan must demonstrate that:

h a 22. m 3 ra n sar.ncva m 5 61

i (1) Grrxmd-water cleanup standards will be schieved, (2) Aestoration is achievable, and l

i3) Restoration is verified through a monitoring program (NRC,1989).

The NRC review procedures for ground-water-cleanup compliance demonstration will be similar to those followed for compliance demonstration of the disposal standards.

l j

However, in general, a more detailed hydrogeologic characterization will be needed for the j

processing site than was previously performed for the disposal demonstration.

1 i

4.3.5 Supplemental Standards Subpart C (40 CFR 192) of the ground-water protection standards allow for the use of supplemental standards in lieu of background levels, MCL's, or ACL's for the compliance j

demonstration. The standards may be either numerical or a narrative performance objective; however, DOE must clearly state the selected supplemental standard in the RAP.

Compliance w;th the supplemental standards should be demonstrated through performance analyses or monitoring (NRC,1989).

Supplemental standards may be applied if site-specific conditions satisfy on-of the criteria in 5192.21. The proposed remedial action must demonstrate compliance with the selected supplemental standard. Additionally, the proposed remedial action must come as close as possible to meeting the otherwise applicable standards in Subparts A and B.

When the 6192.21(f) or (g) criterion is applied, the proposed remedial action for ground-water restoration must also assure protection of human health and the environment. The reviewer should ensure that:

(1) The applicability criterion is appropriate for the site and supported by the hydrogeologic characterization, (2) The supplemental standards have been clearly stated in the RAP document, (3) The proposed remedial action will meet the selected supplemental standard, (4) The remedial actions come as close as possible to meeting the otherwise applicable standards and protecting public health and the environment (if applicable).

4.4 Evaluation Findings

The reviewer may conclude that the RAP provides reasonable assurance of compliance with the EPA ground water protection standards, if the proposed remedial actions satisfy the criteria described in this chapter. The reviewer must document the independent verifications that support the reasonable assurance conclusion in a Technical Evolustion Report (TER). The TER willidentify the technical aspects of the review, any deviations from the review criteria or procedures, and justifications for those deviations. The reviewer can recommend NRC concurrence with the RAP, based on the reasonable h 22, M 3 FMAL SMP. REVt300N 1 62

- - - - -..._.~.--...- - -.--

a i

i i

assurance conclusion. If a reasonable assurance conclusion cannot be reached; the 4

reviewer must:

i e Describe and document any identified inadequacy, i

Provide a detailed description of the technical or regulatory basis for the j

e I

i inadequacy, and i

identify, where possible, a technically-sound alternative approach that might resolve e

the inadequacy.

4 The specific inadequacies are identified as Open lasues in the Water Resources Protection text of the TER. A!! Open issues (including the basis and approach for resolution) are listed in the ' Conclusions' section at the end of the TER. The reviewer documents the following conclusions in the TER before recommending complete concurrence with a RAP:

l (1) Processing and disposal sites have been adequately characterized, including i

characterization of the uranium processing facility, vicinity activities and processes, background water quality, rate and direction of contaminated water flow, and extent of i

existing water contamination; (2) Human health and environmental impacts potentially caused by water contamination I

have been adequately identified and chr.iacterized:

(3) The need for remedial actions for w ster resources has been adequately identified and i

assessed; and (4) Potential implementation of remedial actions for water resources has been adequately

)

evaluated, and the remedial actions selected for implementation have been adequately described in the Remedial Action Plan document.

When the open issues have been resolved, the Water Resources Protection portion of the TER is concluded with a statement that, "The proposed remedial actions comply, with reasonable assurance, with the EPA standards in 40 CFR Part 192.

4.5 References Bear, J., Hvdraulics of Groundwater. New York, New York: McGraw Hill International Book Comp 6ny, 567 p.,1979.

Caldwell, J.A., Reger, R., and Larson, N.B., "The impact of Proposed EPA Ground water a

Standards on UMTRA Project Disposal Cell Design," DOE Remedial Action Program i

Annual Meeting October 18-20,1988..

Canter, L.W., and Knox, R.C., Ground Water Pollution Control. Chelsea, Michigan: Lewis Publishers, Inc., 526 p.,1985.

FINAL SRP, REVtS40N 1 63

= = :,ines 4

l I

4 4

Freeze, R.A. and Cherry, J.A., Groundwater. Prentice Hall: New Jersey,1979.

4

[

Hem, J.D., " Study and Interpretation of the Chemical Characteristics of Natural Wate'," 3

ed., USGS-Water Supply Paper 2254,1985.

t i

Jones, T.L., " Trip Report Albuquerque, New Mexico March 6 9,1989," personal communication.

1 Korte, N., and Ealey, D., " Procedures for Field Chemical Analysis of Water Samples, Grand 1

Junction, Colorado," Bendix Field Engineering Corporation, GJ/TM-07,48 p.,1983.

i Korte, N., and Kearl, P., " Procedures for the Collection and Preservation of Groundwater l

and Surface Water Samples and for the Installation of Monitoring Wells, Grand i

Junction, Colorado," Bendix Field Engineering Corporation, GJ/TC-08,58 p.,1984.

Krauskopf, K.B., Introduction to Geochemistry. New York, New York: McGraw Hill Book I

Company, 617 p.,1979.

Lohman, S.W., Ground-Water Hydraulics. U.S. Geological Survey, Professional Paper 708, j

70 p.,1972.

1 Merritt, R.C., "The Extractive Metallurgy of Uranium," Colorado School of Mines Research I

j institute,1971.

Morrison, R.D., Ground Water Monitorina Technoloav. Prairie Sac, Wisconsin: Timco l

Manufacturing, Inc., III p.,1983.

National Research Council, Drinkina Water and Health. Volume 1, Washington, District of j

Columbia: National Academy Press,939 p.,1977.

I National Research Council, Drinkina Water and Health. Volume 5, Washington, District of Columbia: National Academy Press.157 p.,1983.

?

i Rogoshewksi, P., Bryson, H., and Wagner, K., Remedial Action Technoloav for Waste Disposal Sites. Park Ridge, New Jersey: Noyes Data Corporation, 496 p.,1983.

Scalf, M.R., McNabb, J.F., Dunlap, W.J., Cosby, R.L., and Fryberger, J., Manual of Ground-Water Samolina Procedures. Worthington, Ohio: National Water Well l

Association,93 p.,1981.

i

)

Stallman, R.W., " Aquifer Test Dedqn, Obsmahn, and Data Analysis," U.S. Geological Survey, Techniques of Water Rescarcot investigations, Book 3, Chapter BI,26 p.,

1 1976.

Stumm, W., and Morgan, J.J., Aouatic Chemistry, New York, New York: John Wiley and Sons, Inc., 780 p.,1981.

Todd, D.K., The Water Encyclooedia, Port Washington, New York: Water Information k m 22.1993 FeeAL SMP. MEVWON 1 64 l

Center,1970.

, Groundwater Hydroloav. New York, New York: John Wiley and Sons, Inc.,535 p.,

1980.

TRW, " Environmental Study on Uranium Mill", American Mining Congress: Washington, D.C.,1979.

U.S. Bureau of Reclamation, Ground Water Manual, U.S. Department of Interior,480 p.,

1977.

U.S. Department of Energy (DOE), " Technical Approach Document - Revision 11," UMTRA -

DOE /AL 050425.0002,1989a.

" Moisture Contents and Unsaturated Conditions in UMTRA Project Radon Barriers,"

January 1989b.

U.S. Department of Interior (DOI), National Handbook of Recommended Methods for Water-Data Acauisition.1985 (updated).

U.S. Environmental Protection Agency (EPA), " National Academy of Sciences, Water Quality Criteria," EPA R3/73-033, 594 p.,1972.

, " Final Environmental Impact Statement for Remedial Action Standards for inactive Uranium Processing Sites (40 CFR 192)," EPA 520/4-82-013-1 and 2,1982.

" Final Environmental impact Statement for Standards for the Control of 8yprodu:t Materials from Uranium Ore Processing (40 CFR 192)," EPA 520/1-83 008-1 and 2, 1983.

, Test Methods for Evaluating Solid Waste," SW-846,1984 (updated).

, " Proposed guidelines for exposure assessment," Federal Register, v. 49, n. 227, pp.

46304-46312,1984.

" Draft Alternate Concentration Limit Guidance based on i 264 Criteria: Information Required in ACL Demonstration," 1985.

" Standards for Remedial Actions at inactive Uranium Processing Sites; Proposed Rule,"

Federal Register, Vol. 52, No.185, 36000 - 36008, September 24,1987.

" Ground Water Protection Standards for inactive Uranium Tailings Sites (40 CFR 192) -

Background information for Final Rule," EPA 520/1-88-023, March 1989.

" Statistical Analysis of Ground Water Monitoring Data at RCRA (Resource Conservation and Recovery Act) - Facilities, Interim Final Guidance," EPA /530/SW-89/026, February 1989.

- 22 *

r m sac. m vmum i 65

l U.S. Geological Survey (USGS), " Summary Appraisals of the Nation's Ground-Water Resources," Professional Paper 813.

l U.S. Nuclear Regulatory Commission (NRC), " Descriptions of United States Uranium j

Resource Areas," NUREG/CR-0597,1979.

, Final Generic Environmental Impact Statement on Uranium Milling," NUREG-0706, I

1980.

, Parameters and Variables Appearing in Repository Siting Models," NUREG/CR-3066, l

244 p.,1982.

, Radiological Assessment," NUREG-3332,1983.

l

, Sampling of Uranium Mill Tailings impoundments for Hazardous Constituents," R. Dale 1

l Smith Memorandum to the Division of Waste Management, February 9,1987.

, Draft Technical Position on Altemate Concentration Limits for Uranium Mills, Standard l

l Format and Content Guide and Standard Review Plan for Alternate Concentration LiJ Applications," June 1988.

-, Final Generic Environmental Impact Statement on Decommissioning of Nuclear i

Facilities," NUREG 0586, August 1988.

l j

, " Uranium Recovery and Reclamation Program - A Summary of the History, and Status of the U.S. Uranium Milling and Reclamation Industry," November 18,1988.

i

)

, Standard Format and Content for Documentation of Remedial Action Selection at Title 4

l I Uranium Mill Tailings Sites," Division of Low-Level Waste Management and Decommissioning, Office of NMSS, February 24,1989.

" Recommendations to the NRC for Soil Cover Systems Over Uranium Mill Tailings and

, Low Level Radioactive Wastes - Laooratory and Field Tests for Soil Covers,"

1 NUREG/CR 5432, Vol. 2, January 1991.

Walton, W.C., Groundwater Resource Evaluation. New York, New York: McGraw Hill Book Company,664 p.,1970.

Weber, M.F., personal communication to Malcolm R. Knapp, October 12,1983.

h m 22.1 M 66 FWAL SRP, REVIS40N 1

I i

i i

i 5.0 RADON ATTENUATION AND SITE CLEANUP i

l

.i 5.1 Areas of Review 1

Remedial actions at UMTRA Project sites are required to meet appropriate standards l

(1) the release of radon from tailings disposal cells after reclamation, and (2) the j

cleanup of land and buildings at the processmg sites. This chapter of the SRP establ for:

the performance and documentation of NRC's review of the proposed designs for the l

attenuation of redon by use of soil covers and for the processing site cleanup.

j The two main areas of review for redon attenuation are the geotechnical and j

l radiological properties of the contaminated and cover materials and the computer co other model used for calculating the estimated radon flux from the completed l

l embankment. The specific areas of review for the site cleanup are site characterization, i

standards for cleanup, and verification procedures.

2 9

5.1.1 Radon Attenuation The RAP and/or its supporting documents contain geotechnical and radiological l

information sur')orting the selection of the properties of the tailings and radon barrier l

materials, that affect the radon barrier design. The bases and procedures for determining parameter values of the tailings and radon barrier materials will be reviewed. Informa j

regarding the site investigations and the testing and sampling programs will be revi substantiate the representativeness and validity of the parameter values.

i 1

Procedures for materials placement during remedial activities, as presented in the RA i

construction specifications, will be reviewed to confirm that they are consistent with the i

f' radon barrier design.

The calculational methodology for estimating redon flux or required barrier thickness f

1 j

will be reviewed. Data on the parameter values used in the analysis will be reviewed fo l

appropriateness and statistical validity.

If the radon air concentration approach is selected to demonstrate compliance with 2

EPA standard, the staff will review:

i 1

(a) Description of the model (numerical or analytical) used to approximate the average a l

concentration of radon,

.~

(b) Description of the assumptions made ano the selected modelinput parameter i

l that are specific to conditions at the site including:

stability, wind direction frequency, wind speed, Meteorological conditions:

effective dispersion factors used and justification that selected values of the l

(i) parameters represent the long-term conditions.

Radon source strength and justification for the selected value.

(ii)

.fune 22. N i

67 I

FINAL SRP HEVISIOW4 4

)

(iii)

Factors of safety to account for reasonable assurance in meeting the 0.5 pCi/l off site criterion in the long-term.

(c) References for the methodology used to estimate the concentration.

1 5.1.2 Processing Site Cleanup The remedial action at UMTRA Project sites must meet cleanup standards for radioactive material. The staff will review data defining the extent (area, volume, and j

concentration) of contamination, the cleanup standards to be used at the processing site, the method (s) to be used to verify that the standards have been met, and the adequacy of the quality control program related to site cleanup.

i I

5.2 Acceptance Criteria 5.2.1 Radon Attenuation 5.2.1.1 Regulatory Requirements The purpose of the radon barrier design review is to assure that the disposal of uranium mill tailings will conform to the radon flux attenuation standards promulgated by the EPA.

The basic acceptance criterion pertinent to the radiological aspects of the radon barrier reviews is provided in EPA's 40 CFR 192, Subpart A. Part 192.02 requires demonstration of reasonable assurance that the release of radon-222 to the atmosphere w;ll not:

(a) Exceed an average release rate of 20 pCi/m /s when averaged over the disposal area 2

and over at least a one year period, or, (b) Increase the annual average concentration of radon-222 in air at or above any location outside the disposal site by more than 0.5 pCi/I.

5.2.1.2 Regulatory Guldance There is one NRC regulatory guide and a NUREG document directly applicable to radon attenuation aspects for the UMTRA program. In addition, there is a staff technical position that may provide generic guidance. These reports are:

(a) Regulatory Guide 3.64 (NRC,1989a) " Calculation of Redon Flux Attenuation by Earthen Uranium Mill Tailings Covers." This guide describes methods that are acceptable to the staff for calculating rado 1 fluxes through covers and for calculating the resulting minimum cover thickness. The guide also suggests methods for obtaining the various parameter values used in calculating the redon flux and cover thickness and offers suggested default values for certain parameters. Appendix B discusses the RADON program and gives a sample problem output.

(b) NUREG/CR-3533 (NRC,1984) " Radon Attenuation Handbook for Uranium Mill Tailings Cover Design." This handbook describes the design of earthen covers and j

FINAL SAP. REVISION 1 68 Me 22 W3

their ability to control radon releases from urarnum mill tailings. Equations based on diffusion theory for estimating radon releases from bare and covered uranium mill l

tailings are presented with the RAECOM computer code.

(c) Staff Technical Position (NRC,1989b) " Standard Format and Content for '

Documentation of Remedial Action Selection at Title i Uranium Mill Tailings Sites."

5.2.2 Processing Site Cleanup j

5.2.2.1 Regulatory Requirements The basic acceptance criteria pertinent to the radiological aspects of the processing site

]

remedial action are provided in EPA's 40 CF9192, Subpart B. Part 192.12 requires that:

y t

(a) The concentration of radium-226 in land averaged over any area of 100 square meters shall not exceed the background level by more than-(1) 5 pCi/g, averaged over the first 15 cm of soil below the surface and j

(2) 15 pCi/g, averaged over 15 cm thick layers of soil more than 15 cm below the surface.

l (b) In any occupied or habitable building-(1) The objective shall be an annual average radon decay product concentration, including background, not to exceed 0.02 WL; in any case shall not exceed 0.03 WL.

(2) The level of gamma radiation shall not exceed the background level by more than 20 microroentgens per hour.

Part 192.21 lists criteria for application of supplemental standards in lieu of the standards in Subparts A or B if the remedial action would cause any of these circumstances to exist applicable to soil and building cleanup:

(a) Pose a clear and present risk of injury to workers or to members of the public, notwithstanding reasonable measures to avoid or reduce risk.

(b) Produce environmental harm that is clearly excessive compared to the health benefits to persons living on or near the site, now or in the future.

(c) Remedial cost at a vicinity property is unreasonably high relative to long-term benefits, and the residual radioactive materials do not pose a clear present or future hazard.

(d) The cost for cleanup of a building is clearly unreasonably high relative to the benefits.

(e) There is no known remedial action.

w 22.i***

69 rmtsne.arvmoNt

l (f) Restoration of groundwater quality is technically impracticable from an engineering l

perspective.

(g) The ground water is Class 111.

(h) Radionuclides other than radium-226 and its decay products are present in sufficient i

]

quantity and concentration to constitute a significant radiation hazard from residual i

radioactive materials.

3 j

Part 192.22 lists the supplemental standards as:

3 1

(a) When one or more criteria of Part 192.21 (a)-(e) exist, select and perform remedial l

actions that come as close to meeting the otherwise applicable standard as is reasonable under the circumstances.

(b) When Part 192.21 (h) applies, reduce other residual radioactivity to levels that are as low as is reasonably achievable.

l (c) General determinations may be made that apply to alllocations with specified l

characteristics. When action is proposed under this section for a specific location, DOE j

shallinform owners and occupants and solicit their comments.

l 5.2.2.2 Regulatory Guidance l

Regulatory Guide 1.86, (AEC,1974) " Termination of Operating Licenses for Nuclear l

Reactors," and the Branch Position Paper WM-7601, (NRC,1984) " Guidelines for Decontamination of Facilities and Equipment Prior to Release for Unrestricted Use or Termination of Licenses for Byproduct or Source Materials," are used for cleanup j

guidelines for surface contamination.

l 5.3 Review Procedures i

5.3.1 Radon Attenuation The redon barrier design, as presented in the RAP, is reviewed along with the basic 4

data supporting the design. Methodology used to calculate the exit radon flux through the i

tailings / cover system or the ambient air concentration of radon-222 at the site boundary is also reviewed.

i 5.3.1.1 Evaluation of Parameters The selection of values for tailings and cover material properties will be considered acceptable if the estimates of all values of the material parameters that are used in the calculational methodology lead to a reasonably conservative estimate of the radon flux.

The scope and technique of site investigations must be such that the field investigation and testing program provide the necessary data to support all conclusions. Whenever site-FMAL SMP, REVlWON 1 70 Jw= 22. im f

1 1

specific measured parameter values are utilized, they should be accompanied by supporting information describing the test method, its precision and accuracy, and its applicability for representing a lor'g term, large area average. The boring, sampling, and testing programs will be reviewed to assure that appropriate analytical methods have been employed and that sufficient and representative data have been collected for determining material property values of both the cover and contaminated materials. When sufficient test data are not available, conservative values may be chosen for use in the analyses if their use is justified.

The reviewer will assess whether parameter values are consistent with anticipated construction specifications and represent long-term conditions. The long-term attenuating capability of these materials needs to be justified. Short-term determinations of parameter values should not be considered because of the long-term specifications of the standards.

The reviewer will also ascertain that the basis for obtaining parameter values and how the values are used in the analyses is addressed. The reviewer will determine whether moisture-dependent parameter value's determinations considered the long-term moisture content of the materials at the disposal site (e.g., emanation coefficient). The reviewer will confirm that the parameter values ate used in a conservative and consistent fashion throughout the calculations.

The staff members assigned the health physics and geotechnical review duties will confer on the radon attenuation design and analysis, but each will have their areas of review emphasis. The geotechnical information on physical characteristics of the contaminated and cover materials as discussed in Chapter 2.0 of this SRP and the radiological information on contaminated materials will be reviewed. Also, the properties of the other layers of the cover will be considered in the context of how they will influence the integrity and long-term moisture content of the radon barrier. The review will extend to vicinity property material for those sites that have large volumes of off-site material that will be placed in the disposal cell.

Specific parameter considerations are as follows:

Lono-term Moisture - The methodology used in the estimation of the long-term moisture content of the tailings material and the radon barrier material will be reviewed.

The staff will determine whether adequate documentation of the basis for empirical relationships used in the analysis has been provided. The methodology to determine the moisture content will be reviewed to verify that consideration has been given to meteorological and hydrological conditions at the disposal site, bulk density, type of material, and the iruluence of overlying materiallayers. The staff will conduct independent calculations using methods described bolow. Estimated values of the long-term moisture content will be compared to present in-situ values to assure that the long term value does not exceed the present field value derived from samples taken at a depth of 120 to 500cm (but not close to water table). Also, this borrow site value should be correlated to the conditions at the disposal site.

Soil moisture values used in the design will be considered acceptable if they represent the long-term moisture contents that conservatively bound the lower moisture retention capacities of the materials. The values should represent the lowest moisture contents that FINAL SRP. REVISK)N 1 71 M w 22.1993

i 4

the soils can be expected to experience for any one year period riuring the long-term design life of the project.

Values of moisture contents for the tailings material will be considered acceptable if l

they represent reasonably conservative estimates of the equilibriurn moisture after t tailings have been stabilized.

The reviewer will consider the following methods acceptable for predicting the long-l term soil moisture, given the limitations stated above; (a) Laboratory procedures ASTM D-3152 (fine-textured soils) and ASTM D-2325 (coarse-1 and medium-textured soils) conducted at 15-bar suction corresponding to the moisture

)

content at which permanent wilting of plants occurs (Baver,1956).

7 (b) The empirical relationship (Rawls and Brakensiek,1982) established that predicts water

~

retention values of a soil on a volume basis:

1 c = 0.026 + 0.005x + 0.0158y 1

4 where:

c = predicted 15-bar soil water retention value (cms / cms) x = percent clay in the soil y = percent organic matter in the soil j

i The 15-bar water retention value will be considered an acceptable estimate of the long-l term moisture content of cover material when estimated by this method. The reviewer should be aware that this volumetric moisture conter". must be converted to a weight percentage for some applications.

^

l This method takes into consideration the particle size distribution of the soil. Clay

(

l particle sizes are defined here as those finer than 0.002 mm in diameter, Organic content measurement is generally determined by reaction with hydrogen i

peroxide or by exposure to elevated temperature. Other tests,if adequately justified, ma l

i be acceptable.

Densitv. Soecific Gravitv. and Porosity - Dry densities of the cover soils and tailings f

material determined from Standard Proctor Test data (ASTM D-698) or Modifie Test data (ASTM D-1577) will be considered acceptable. The staff will accept compacting l

the cover materials to a minimum of 95% of tne maximum dry density as determined by ASTM D-698 or to a minimum of 90% of the maximum dry density as determined by ASTM D-1577. When the tailings materials are moved from one location to another, they should be compacted to a minimurr, of 90% of the maximum dry density as determined b l

{

ASTM D-698. Field densities that will be achieved when the materials are compacted according to these specifications should be used in the methodology. Alternatively, if the pile is to be stabilized-in-place, the in-situ bulk densities should be used in the analyse

== 2 2.1 *n i

72 rm w. mvam 5

The staff assumes reference specific gravities of 2.65 for the tailings and cover materials unless specific altemative values and a documented basis are provided in analysis. An acceptable method for estimating the porosity of the material base bulk density and specific gravity is given in Regulatory Guide 3.64.

Material Thickness - The estimate of the tailings thickness will be considered acceptable if determined from estimates of total tailings production and the are the pile or by using representative values from boring logs of sufficient number 500 cm represents an equivalent infinitely thick tailings source, (NRC,1989) and s is a more conservative approach, it may be used without more specific analyses of tailings sources. However, if material with low radium-226 content will be placed a separate layer, that layer thickness estimate should not use the equivalent in source value.

The estimated soil cover thickness in the remedial action design will be considered acceptable if the thickness reduces the calcuiated long-term radon flux to levels that the EPA standard.

Radon Diffusion Coefficient. D - The radon diffusion coefficient, "O," of the cover soil is of centralimportance for determining the cover thickness necessary to achieve a give radon flux reduction. The D value is most accurately determined from direct measurements as described in NRC,1984 (Section 3). The soil should be testeo at the design compaction density in a range of moisture contents that bounds the lower m retention capacity of the soil.

Documentation of experimental precision and accuracy for measurement of the diffusion coefficient for candidate cover soils and tailings material should be provided.

evaluating the measurements, the long-term variability of this parameter should be f actored into the estimation.

Models based upon physical characteristics of the soil or upon empirical correlation based on previously measured values of D may be acceptable for estimating the d coefficient when measured values are unavailable. A correlation that is acceptabl expected range of soit densities is one proposed by NRC (1984, Section 4) wh the moisture saturation ratio. The estimation of the diffusion coef will be considered acceptable if it represents the long-term in-situ properties of the materials.

Radium Content - Values of the radium activity within tha tailings (pCilg) can be measured (rectly from tailings samples and.ther large-volume sources of cont material by the redon equilibrium method or by direct gamma spectroscopy (contracto procedures, RAC-015 have been approved by NRC staff).

Since the disposal cell performance standard deals only with radon generated contaminated tailings material, it is acceptable to neglect the radium activity in the soils provided the cover soils are obtained from background materials not a ore formations or other radium-enriched materials.

.kn. n. inss 73 FINAL SAP, REVI640N

_=-..

Emanation Coefficient. E - The value of the emanation coefficient, "E," will be considered acceptabic, if shown to be representative of the tailings material and if supported by field and/or laboratory test records. Since the value of the coefficient is moisture-dependent, the value of the long term moisture content must be considered when determining radon emanation. The emanation coefficient may be obtained by either the equilibration method or the prediction method as discussed in Austin and Droullard,1978.

If a measured value of the emanation coefficient is not provided in the analysis, use of a reasonably conservative reference value of 0.35 is considered acceptable by the staff.

Ambient Radon - The computer code requires input of the radon concentration above the top layer. A measured background value can be used, but a value of zero is conservative and is recommended.

The computer code also requires the input of other fundamental parameters. These 4

include the redon decay constant, with an accepted value of 2.1x10 /s, and the equilibrium distribution coefficient, with an accepted value of 0.26. The precision also must be designated. The precision number that should be entered is the level of computational error that is acceptable and a value of 0.001 is recommended.

5.3.1.2 Evaluation of Radon Attenuation Model The accepted basis for calculating radon flux and minimum cover thickness is one-dimensional, steady-state gas diffusion theory. NRC (1984) presents an analytical method and the computer code RAECOM for determining the surface redon flux from covered tailings, or alternatively, the cover thickness required to satisfy a specified radon flux criterion. The staff considers this analytical method and the RAECOM code acceptable for determining the necessary cover thickness to reduce radon flux to acceptable limits. The staff will use the comparable RADON code (NRC,1989a) to validate the analysis. The main difference between the two codes is that RADON does not have the optimization for cost-benefit.

The staff will consider whether the average measured parameter values are conservative. NRC staff has accepted use of the average values plus or minus (whichever is more conservative) the standard error of the mean, but prefer the use of values that represent the 95% confidence level for the critical parameters of long term moisture and redon diffusion coefficient.

Other methods that estimate the average surface radon release from the covered tailings disposal site or which estimate the annual average concentration of redon in air at or above any location outside the disposal site may be acceptable,if it can be shown that these methods produce reliable estimates of radon flux.

5.3.2 Processing Site Cleanup 5.3.2.'l Radological Site Characterization The reviewer will ascertain that the background level of radium in soil in the general area of the site is determined using representative soil samples from nearby Am 22. M FWAL SftP, fEVISION 1 74

!^

h uncontaminated areas. The value is used to derive the cleanup standard. The areal extent 1

i and depth of radium-226 contamination above the standards in the soil on the site, as well as in the tai;ings pile, must be determined from representative and adequate sampling.

l Also, the reviewer will determine that appropriate analysis of thorium-230 (also thorium-i I

232 if presence suspected) has been performed.

2 The level of contamination in build;ngs will be reviewed. Structures and materials on j

the site must be designated for disposal in the tailings embankment, for decontamination, or in the case of hazardous or toxic substances, for disposal / treatment in an appropriate i

facility. Contaminated asbestos, properly packaged, has been allowed to be placed with j

the tailings if precautions in its handling and placement are followed.

)

j The staff will determine whether conclusions in the RAP are adequately substantiated j

by the characterization data or otherwise justified in an acceptable manner.

)

5.3.2.2 Standards Used for Cleanup i

l The reviewer will verify that DOE has committed to clean up and place within the disposal cell all materials on the processing site that are in excess of the EPA Radium-226 standards (40 CFR 102 Subpart B). There should also be a commitment to clean to l

appropriate standards any surface cipha or bota-gamma contamination of equipment and i

structures to be released for unrestricted use.

If the application of supplemental standards is proposed for an area, the reviewer will determine if adequate data are provided to determine that one or more of the criteria of 40 j

CFR 192.21 appropriately applies to the area in question.

c When suspected naturally occurring ore is to remain on the site, the reviewer will determine if appropriate procedures are presented for its identification, such as use of l

uranium-238/ radium 226 ratios, or visuM criteria. Staff has previously defined naturally occurring ore as material that has not been disturbed by mining processes. DOE is not j

responsible for the remediation of materialidentified as naturally occurring ore.

If elevated levels of uranium are expected to remain after the radium-226 criteria has been met, the reviewer will determine whether appropriate criteria for cleanup are presented in the RAP. An acceptable cleanup standard for total uranium is 10 pCi/g in the j

top 15 cm of soil and 30 pCi/g in subsequent 15 cm layers. This standard is based on the j

amount of uranium that would decay to radium levels meeting the EPA standard.

l if areas ; hat already meet the radium criteria still have elevated thorium levels, the RAP should contain criteria such that remediation will continue until the amount of radium j

(residual and from thorium decay) that would be present in 1000 years meets the cleanup l

l standard. An acceptable alternate criteria for a deeply buried thorium deposit would be to determine that the amount of radon that could axit into a 100 square meter structure built over that deposit would meet the EPA radon progeny standard for habitable structures.

3 FINAL SAP, REVISM)N 1 75 u = 22.1893 1

l

---e

,,._m

1 I

l f

5.3.2.3 Verification The procedures used to verify that the cleanup has been accomplished according to the l

standards will be examined to assure that the resulting data will provide reasonable assurance that all applicable standards will be met. Any detailed information on verification procedures presented elsewhere, should be appropriately referenced and have been previously acceptable to NFIC.

Staff will determine that the RAP indicates that a percentage of verification samples will be analyzed for thorium and that a statistical basis for choosing the percentage of thorium samples is provided. For sites with known elevated levels of thorium, at least j

l 10% of the samples analyzed for thorium content is acceptable.

i l

If a new verification procedure is proposed, for example when cobbly soil is l

encountered, the reviewer will determine that the proposed new method will provide i

reasonable assurance that the EPA standards have been met.

If alpha and beta-gamma contamination on the surfaces of structures and equipment is to be remediated, adequate testing should be planned to substantiate that release for unrestricted use standards have been met.

If habitable buildings are to remain on site, the reviewer willinsure that the RAP indicates that the radon daughter concentration will be measured after remedial action and evaluated against the EPA standard for radon progeny and that interior gamma levels will i

j also be demonstrated to meet the EPA standard.

i

5.4 Evaluation Findings

The staff's review of redon attenuation and site cleanup should verify that sufficient information has been provided in the RAP and supplemental documents such that the following findings can be made:

I 5.4.1 Radon Attenuation if the staff evaluation of the radon barrier analysis in the RAP confirms that the standards and regulatory guidelines have been met with reasonable assurance, i

documentation of the review will state that:

(a) the investigations performed and assumptions made justify the choice of parameter l

values used to determine required cover thickness and the resultant redon flux and/or ambient air concentration of Radon-222:

(b) the statistical and computer code analyses are acceptable and contain adequate levels of assurance; and l

(c) the remedial action design represents a feasible plan for assuring long term performance with respect to radon flux attenuation.

i 4

h 22,i m 76 FINAL SRP, MEVISION 1

-g-

+w-i

Staff reservations about any portion of the analysis or design will be stated in sufficient detail to make clear the precise nature of the staff's concern.

5.4.2 Processing Site Cleanup If the staff evaluation of the processing site cleanup design confirms that applicable standards will be met, the staff will document that the RAP has met the following objectives:

(a) Radiological characterization has been conducted at the processing site to acceptably identify the subsurface boundary of the tailings pile as well as the depth and area of 4

the mill yard, ore storage, and windblown or other contaminated areas. The results of

)

this characterization have been used to plan the excavation control monitoring and the final verification of the land and buildings.

(b) DOE has committed to the cleanup of the processing site in accordance with the EPA standard in 40 CFR 192 Subpart B, or supplemental standards, and cleanup of any surf ace contamination in excess of the recommended standards.

(c) The procedures identified in the RAP for the final radiological verification are consistent with generic procedures (RAC-015) that have previously been reviewed and approved by the staff.

NRC staff can then state that they are prepared to concur with the site cleanup aspects of the proposed remedial action. However, if the objectives have not been met satisfactorily, any reservations or issues will be stated in sufficient detail and clarity to convey the precise nature of the staff's concern.

5.5 References Austin, S.R., and Droullard, R.F., " Radon Emanation from Domestic Ore Determined by Modification of Closed-Can Gami..a Only Assay Method," U.S. Bureau of Mines, Report of Investigations 8264,1978.

Baver, L.D., Soil Physics. John Wiley and Sons, N.Y., pp. 283-303,1956.

Code of Federal Regulations, Title 40, Protection of Environment, Part 192," Health and Environmental Protection Standards for Uranium Mill Tailings," 1983.

Rawls, W.J., and Brakensiek, D.L., " Estimating Soit Water Retention From Soit Properties,"

Journal of the Irrigation and Drainage Division, Proceedings of the American Society of Civil Engineers, vol 108, No.lR2,1982.

U.S. Atomic Energy Commission, Regulatory Guide 1.86, " Termination of Operating Licenses for Nuclear Reactors," June 1974.

.km 22.1993 77 FINAL SRP. REVISK)N 1

i U.S. Nuclear Regulatory Commission, " Radon Attenuation Handbook for Uranium Mill Tailings Cover Design," NUREG/CR-3533, April 1984a.

--- Guidelines for Decontamination of Facilities and Equipment Prior to Release for Unrestricted Use or Termination of Licenses for Byproduct or Source Materials, Branch Position Paper WM-7601, September,1984b.

-- Monitoring Methods for Determining Compliance With Decommissioning Cleanup Criteria at Uranium Recovery Sites," NUREG/CR-4118 (PNL-5361), June 1985.

-Office of Nuclear Regulatory Research, " Calculation of Radon Flux Attenuation by Earthen Uranium Mill Tailings Covers.", Regulatory Guide 3.64, March 1989a.

-Staff Technical Position, " Standard Format and Content for Documentation of Remedial Action Selection at Title 1 Uranium Mill Tailings Sites," 1989b

-- Recommendations to the NRC for Soil Cover Systems Over Uranium Mill Tailings and Low-Level Radioactive Wastes," NUREG/CR 5432, Vol.13, February,1991.

FINAL SRP. REVISK)N 1 78 h 22,1993

APPENDlX A COMMON UMTRA PROJECT ACRONYMS Alternate Concentration Limit ACL Low Level Uranium Recovery LLUR LTSP -

Long-term Surveillance Plan Maximum Concentration Limit MCL Point of Compliance POC Point of Exposure POE Remedial Action Contractor RAC RAP Remedial Action Plan Remedial Action Section RAS Stabilization in Place SIP SOS Stabilization on Site Technical Assistance Contractor TAC Technical Evaluation Report TER UMTRA - Uranium Mill Tailings Remedial Action UMTRCA - Uranium Mill Tailings Radiation Control Act of 1978 w 22, tens FMAL SRP, MEVISKW l A-1

J w 22. ms FMAL SAP, PUEVtS40N 1 A-2

APPENDIX B SEISMIC-TECTONIC GLOSSARY CAPABLE FAULT - A fault which has exhibited one or more of the following characteristics:

1) Movement at or near the ground surface at least once within the past 35,000 years or movement of a recurring nature within the past 500,000 years;

2) Macro-seismicity instrumentally determined with records of sufficient precision to demonstrate a direct relationship with the fault;

3) A structural relatienship to a capable fault according to characteristics (1) or (2) of this paragraph such that movement on one could be reasonably expected to be l

accompanied by movement on the other. [10 CFR 100, App. A, lil(g)]

l l

FAULT - A tectonic structure along which differential slippage of the adjacent earth material has occurred parallel to the fracture plane. It is distinct from other types of ground disruptions such as landslides, fissures, and craters. A fault may have gouge or breccia between its two walls and includes any associated monoclinal flexure or other similar geologic structural feature [10 CFR 100, App. A l!l (e)]

MAXIMUM CREDlBLE EARTHOUAKE (MCE) - That earthquake which would cause the maximum vibratory ground motion based upon an evaluation of earthquake potential considering the regional and local geology and seismology and specific characteristics of local subsurface material. [10 CFR 40, App. A, Criterion 4(e)]

SURFACE FAULTING - A differential ground displacement at or near the surface that is caused directly by fault movement and is distinct from nontactonic types of ground disruptions, such as landslides, fissures and craters. (10 CFR 100, App. A lil(f)]

TECTONIC PROVINCE - A region of the North American continent characterized by a relative consistency of the geologic structural features contained therein. [10 CFR 100, App. A Ill (h))

TECTONIC STRUCTURE - A large scale dislocation or distortion within the earth's crust.

Its extent is measured in kilometers (miles). [10 CFR 100, App. A Ill(i))

FDdAL SAP, MVS40N 1 g.j June 22.1993

l

\\

J FNAL segp, pgyggg i B-2 h 22,1993

i APPENDIX C GLOSSARY OF WATER RESOURCES PROTECTION TERMS Aquifer - A formation, group of formations, or part of a formation that j

contains sufficient saturated permeable material to yield significant quantities of water to wells and springs.

Background Quality - The chemical and hydrochemical characteristics of a material (generally water or soil) that would exist independent of the effects of the j

designated facility.

i Bedioad - Sediment that moves on or near the stream bed and is in almost l,

continuous contact with the bed.

t' j

Brackish Water - Water that contains more than'1,000 but less than 10,000 l

milligrams per liter of dissolved solids.

Brine - Water that contains more than 35,000 milligrams per liter of dissolved j

solids.

i Cation exchange capacity (CEC) - the number of milliequivalents of cations that can be exchanged from solution to a solid with a dry mass of 100 grams.

l Confined - The condition in which the static water level or potentiometric 1

surface in a hydrogeologic unit is above the top of the unit; artesian.

Confined Aquifer - An aquifer bounded above and below by hydrogeologic units i

of distinctly lower permeability than that of the aquifer.

1 l

Confining Unit - A hydrogeologic unit with distinctly low permeability above J

l or below one nr more aquifers.

l I

Contaminant Plume - A contaminated area or volume of a stream or aquifer.

Desorption - Release of gas molecoles, ions, or molecules into solution that t

i had previously adhered to a solid surface.

Discharge Area - That portion of a subsurface drainage basin or hydrogeologic i

system in which the not saturated flow o' groundwater is directed toward the water l

table.

\\

l Dispersion Coefficient - A measure of the spreading of a flowing fluid, which equals the sum of the coefficient of molecular diffusion and the product of dispersivity times the average interstitial velocity in a porous medium.

j Dispersivity - A proportionality constant that describes the mechanical mixing of solutes and heat during advective transport, which equals the ratio between the i

== 2 2. 1 ** 3 m asar.mvsm i C-1

i t

4 coefficient of mechanical dispersion and the average interstitial velocity along a flow path.

Distribution Coefficient - The equilibrium sorption ratio of the amount of 4

solute sorbed by the solid per unit weight of solid and the quantity of solute dissolved in solution per unit volume of solution.

a Effective Porosity - The ratio of (1) the total volume of voids that conduct fluid flow and advoctive solute and heat transport to (2) the total volume of the porous i

medium.

i Evapotranspiration - The amount of water discharged to the atmosphere as a result of evaporation from earth materials and surface water bodies and transpiration l

from plants.

Flow Path - The subsurface, macroscopic course a water molecule or solute would follow in a given water velocity field.

Freshwater - Water that contains less than or equal to 1,000 milligrams per liter of dissolved solids.

Groundwater - Water that occurs below the surface of the earth, including water within the unsaturated and saturated zones and excluding primordial water and I

waters bound within crystallattices.

l Groundwater Divide - A ridge in the water table or potentiometric surface from which groundwater flows in opposite directior.s.

I Groundwater Mound - A rise in the water table or other potentiometric surface l

created by groundwater recharge.

l Head, Static - A measure of the potential of water represented as the height above a standard datum of the surface of a column of water that can be supported by l

the static pressure at the point of measurement; the sum of the elevation head and pressure head.

i Hydraulic Conductivity - A proportionality constant that relates hydraulic gradient to specific discharge, which may be expressed as the volume of water at an j

existing kinematic viscosity that will move in unit time under a unit hydraulic gradient j

through a unit area measured normal to the direction of flow for an isotropic medium and homogenous fluid.

Hydraulic Gradient - The change in static head per unit distance in a given direction, which is generally assumed to coincide with the direction of maximum rate of decrease in head.

i I

Hydrodynamic Dispersion - The spreading of a solute or thermal energy during transport caused by mechanical dispersion and molecular diffusion as described on a k= 22 1**3 C-2 r m sne,nevaxm i

macroscopic scale.

Hydrogeologic Unit - Any discrete and continuous porous medium or porous zone that influences the storage or movement of groundwater because of its porosity or permeability.

Infiltration - The downward entry of water into soil, sediment, or rock. Leakage - The uncontrolled transfer of water from one aquifer to another.

Matrix Potential-The energy required to extract water from a porous medium against capillary and adsorptive forces of the medium.

Mechanical Dispersion - Physical mixing of solutes or thermal energy during advoctive transport caused by variations of flow velocities at the microscopic scale.

Moisture Content - The ratio, expressed as a percentage, of (1) the weight of water to (2) the weight of solid particles in a given volume of a porous medium.

Perched Groundwater - /. saturated body of unconfined groundwater separated from an underlying saturatsd body of groundwater by an unsaturated zone.

Piezometer - A device emplaced in the subsurface to measure accurate changes in groundwater levels.

Porosity - The ratio of the total volume of voids to the total volume of a porous medium.

Potentiometric Surface - An imaginary surface representing the static head of groundwater described by the level to which water would rise in a piezometer.

Protective Action - Any action implemented to prevent, control, or mitigate water contamination.

Recharge Area - That portion of a drainage basin or discrete hydrogeologic system in which the net saturated flow of groundwater is directed away from the water table.

Saline Water - Water that is generally considered unsuitable for human consumption or for irrigation because of 'ts high content of dissolved solids ranging from 10,000 to 35,000 milligrams per liter.

Seep - An area where water percolates to the land surface at flow rates less than 1 liter per minute per square meter.

Semiconfined Aquifer - An aquifer that is partially bounded above or below by a confining unit.

w 22. m a j

C-3 FMAL SRP. REVISION 1

i Sole Source Aquifer - As determined by the U. S. Environmental Protection j

Agency, an aquifer that supplies at least 50 percent of the drinking water for an area.

Sorption - One or more physiochemical processes, excluding precipitation of l

stoichiometric (fixed composition) solid phases, in which solutes are removed from a liquid or gas phase by interaction with a solid phase or phases, i

Specific Discharge - The rate of discharge of groundwater per unit area of a porous medium measured perpendicular to the direction of flow.

Specific Storage - The volume of water released from or taken into storage per j

unit volume of the porous medium per unit change in head.

Specific Yield - The retic the volume of water that a saturated porous l

medium will yield by gravity flow to the total volume of the porous medium.

Spring - A discrete area where groundwater discharges naturally onto the land surface or into a body of surface water at ' low rates greater than or equal to 1 liter per l

minute per square meter.

I Storage Coefficient - The volume of water an aquifer releases from or takes into storage per unit surface area of the aquifer per unit change in head; storativity.

Total Dissolved Solids - The total concentration of dissolved constituents in solution, which is generally expressed in milligrams per liter.

Transmissivity - The rate at which water of a given kinematic viscosity is transmitted through a unit width of an aquifer under a unit hydraulic gradient.

Unconfined - The condition of water in the zone of saturation whose upper surface is the water table.

I Unsaturated Flow - The movement of water in a porous medium whose pores are i

not completely filled with water.

l Unsaturated Zone - The portion of hydrogeologic systems between the land surface and the deepest water table, which includes the capillary fringe and may contain zones in which water pressure is locally greater than atmospheric pressure; vadose zone.

l I

i 1

2 h 22.1993 C-4 f

FINAL SAP, REVISION 1 4

J

9 1

i i

1 1

1 k

.i.

?

3 i

t i

.i ii i

i f

f i

i 1

APPENDIX D t

Chapter 40 PART 192

)

f Health and Environmental Protection Standards for Uranium Mill Tailings

}

(EPA,1987) 1 h 22 W 3 D.]

FWAL SRP. HEV440N 1

40 CFR 192; Sept. 24,1987 NMSSILLUR Ref. Doc.

Page 3 This document was compiled from published Federal Register ~ Mces as an internal reference resource for the NRC Low Level Uranium Recovery e anch. Although every effort has been made to ensure completeness and accuracy, the user should refer to the appropriate Federal Register notices as the primary source for making authoritative citations.

Proposed Rule: FR vol. 52, no.185 TITLE 40 PART 192 HEALTH AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM MILL TAILINGS Subpart A - Standards for the Control of Residual Radioactive Materials f

from inactive Uranium Processing Sites sec.

192.00 Applicability.

192.01 Definitions.

192.02 Standards.

Subpart B - Standards for Cleanup of Land and Buildings Contaminated with Residual Radioactive Materials from inactive Uranium Processing Sites Sec.

192.10 Applicability.

192.11 Definitions.

192.12 Standards.

Subpart C - Implementation Sec.

192.20 Guidance for implementation.

192.21 Criteria for applying supplemental standards.

192.22 Supplemental standards.

192.23 Effective date.

Authority: Section 275 of the Atomic Energy Act of 1954,42 U.S.C. 2022, as added by the Uranium Mill Tailings Control Act of 1978, Pub. L.95-604.

148 FR 590 Jan. S.1963 se amended $2 FM 36000 Septente 24,1987)

Jaa22,iss3 D-3 FINAL SRP. REVISION 1

1 40 CFR 192; Sept. 24,1987 NMSSILLUR Ref. Doc.

Page 4 1

completion of control activi-Subpart A - Standards for the Con.

ties.

l trol of Residual Radioactive Materi.

als from inactive Uranium Process-(e)

Depository site means a disposal ing Sites site (other than a processing site) l selected under Section 104(b) or l

l 105(b) of the Act.

t l

5 192.00 Applicability i

(f)

Curie (C// means the amount of

'l This subpart applies to the control of radioactive material that produces residual radioactive material at designated 37 billion nuclear transformations processing or disposal sites under Section per second. One picocurie (pCi) =

108 of the Uranium Mill Tailings Radiation 10 " Ci.

l Control Act of 1978 (henceforth des-ignated "the Act"), and to restoration of (g)

Remedia/ period means the period such sites following any use of subsur-of time beginning March 7,1983 l

face minerals under Section 104(h) of the and ending with the completion of Act.

requirements specified under the remedial action plan.

,,,,,,,y i

(h)

Remedial Action Plan means a i

written plan for a specific site that j

i 192.01 Definitions incorporates the results of site ch-

?

aracterization studies, environmen-(a)

Unless otherwise indicated in the tal assessments or impact subpert, all terms shall have the statements, and engineering as-same meaning as Title I of the sessments into a plan for disposal

}

Act. Reference to Part 264 of the and cleanup which satisfies the l

Code of Federal Regulations is to requirements of Subparts A and B.

that Part as codified on January 1, 1983.

(i)

Post-disposal period means the pe-l riod of time beginning immediately l

(b)

Remedial action means any action after the completion of the require-performed under Section 108 of monts of Subpart A and ending at the Act.

completion of monitoring require-ments established under 1192.02-l (c)

Control means any remedital action (b).

i intended to stabilize, inhibit future misuse of, or reduce emiskions or (i)

Ground water is subsurface water j

effluents from residual radioactive within a zone in which sub-s materials.

stantially all the voids are filled with water under pressure equal to j

(d)

Disposal site means the region wit.

or greater than that of atmospheric i

hin the smallest perimeter of l

pressure.

residual radioactive material (ex.

j cluding cover materials) following

E'"**""*""***"'"""*"

i l

4 F96At OfqP, FIEVISION 1 g.4 2

40 CFR 192; Sept. 24,1987 NMSSILLUR Ref. Doc.

Page 5 (ii)

Increase the enqual 5 192.02 Standards average concentra-tion of radon-222 (a)

Control of residual radioactive in air at or above materials and their listed con-stituents shall be designed' to:

any location outside the disposal site by i

more than one-half (1)

Be effective for up to one picocurie per liter.

thousand years, to the extent reasonably achievable, and, in any case, for at least 200 (3)

Conform to the ground-water protection provisions i

years, and of 5264.92 - 1264.95 of Part 264 of this chapter, (2)

Provide reasonable assurance that releases of radon--222 except that, for the from residual radioactive purposes of this subpart:

materials to the atmosphere will not:

(i)

To the list of const-ituents referenced in 2

1264.93 of th s (i)

Exceed ar. average release rate of 20 picocuries per chapter are added square meter per second, or molybdenum, radi-um, uranium, and nitrate.

TABLE A.

CONSTITUENT LIMIT Combined radium-226 5 pCi/L and radium-228 Combined uranium-234 30 pCi/L i

and uranium-238 Gross Alpha Activity 15 pCi/L (excluding radon and uranium)

Nitrate (as N) 10 mg/L Molybdenum 0.1 mg/L m nr. m D5 FINAL 1AP. REVt$m 1

1 P,:ga 6 40 CFR 192; Sept. 24,1987 NMSSILLUR Rsf. Doc.

period of time which shall (ii) To the concentration limits constitute the post-disposal provided in Table 1 of 126-period, which is adequate 4.94 of this chapter are to demonstrate that initial added the constituent limits in performance of the disposal Table A of this subpart, is in accordance with the i

design requirements of (iii) The Secretary shall determine 5192.02(a).

what listed constituents are present in the tailings at a If the ground-water standards es-(c) disposal site.

tablished under provisions of 5192.02(a) are found or projected (iv) A monitoring program shall be to be exceeded, as a result of the established upgradient of the monitoring program established for disposal site adequate to de-termine background levels of the post-disposal period under 1192.02(b), a corrective action listed constituents.

j program to restore the disposal to the design requirements of

{

(v) The Secretary may propose 1192.02(a) and, as necessary, to and, with the Commission's 1

j concurrence, apply alternative clean up ground water in conformance with Subpart B shall concentration limits, provided j

that, after considering prac-be put into operation as soon as j

ticable corrective actions, the practicable, and in no event later than eighteen (18) months after a

, Commission determines that finding of exceedance.

these are as low as reason-ably achievable, and that, in

(** " 5 "

5 * * =

5 2 * ** ***"** 2 * -

1 any case, 5264.94 (b) is 1987!

satisfied, and Subpart B - Standards for Cleanup

'"U );)"

of Land and Buildings Contaminet-de e in efer ed With Residual Radioactive Ma-enced paragraphs of Part 264 terials From inactive Uranium Pro-of this chapter as those of the

" Regional Administrator" with cessing Sites respect to " facility permits" shall be carried out by the Commission.

I 192.10 Applicability (4)

Comply with the performance This subpart applies to land and standard in 1264.111(a) and buildings that are part of any processing (b) of this chapter.

site designated by the Secretary of En-orgy under Section 102 of the Act. Sec-(b)

The Secretary shall propose and, tion 101 of the Act, states,in part, that following the concurrence by the

" processing site" means -

Commission, implement a monitor-ing plan, to be carried out over a M w 22,1993 D-6 FMAL SMP. MEVISION 1

4 Page 7 40 CFR 192; Sept. 24,1987 NMSSILLUR Ref. Doc.

4 of the Act or in Subpart A.

(a)

Any site, including the mill, containing residual radioactive ma-Land means (1) any surface or terials at which all or substantially (b) subsurface land that is not part of all of the uranium was produced a disposal site and is not covered j

for sale to any Federal agency by an occupiable building, and (2)

J l

prior to January 1,1971, under a subsurface land that contains l

contract with any Federal agency, ground water contaminated by list-except in the case of a site in or ed constituents from residual j

near Slick Rock, Colorado, unless-radioactive material from the pro-I cessing site.

l (1) Such site was owned or controlled as of January 1,1978, or is there-ww*ing Level (WL/ means any l

(c) after owned or controlled, by any combination of short-lived radon Federal agency, or decay products in one liter of air that will result in the ultimate (2) A license (issued by the (Nuclear emission of alpha particles with a Regulatory) Commission or its total energy of 130 billion electron predecessor agency under the volts.

l Atomic Energy Act of 1954 or by the States permitted under Section So// means all unconsolidated l

274 of such Act) for the materials normally found on or (d) i production at site of any uranium near the surface of the earth inclu-l or thorium products derived from ding, but not limited to, silts, i

ores is in effect on January 1, clays, sands, gravel, and small l

1978, or is issued or renewed l

after such date; and rocks.

I (e)

Class /// pround water

means I

(b) any other real property or improve-ground water that is not a current ment thereon which -

or potential source of drinking water because (1) the concen-i (1) is in the vicinity of such site, and tration of total dissolved solids is i

in excess of 10,000 mg/L, (2)

(2)is determined by the Secretary,in widespread, ambient contamina-j consultation with the Commission, tion not due to activities involving l

to be contaminated with residual residual radioactive materials from l

radioactive materials derived from a designated processing site exists i

such site. '

that cannot be cleaned up using i

l treatment methods reasonably em-i"

6'*

5 *83 ployed in public water-supply sys-

{

tems, or (3) the quantity of water available is less than 150 gallons i

l 192.11 Mh

{

per day.

i Unless otherwise indicated in this (a) re m s o a e, toes sa m 3 o00 s m

, 24 J

subpart, all terms shall have the l

" 73 same meaning as defined in Title 1 2

i h w 22,1 93 D7 FINAL sRP, REVIS80N 1 i

T 4

40 CFR 192; Sept. 24,1987 NMSSILLUR Ref. Doc.

Page 8 nated processing site shall not exceed the provisions of $264.92 - $264.94 of i 192.12 Standards this chapter as modified by Remedial actions shall be conducted 1192.02 (a)(3)(i) and (ii),

so as to provide reasonable assurance except for the purposes of that, as a result of residual radioactive this subpart; l

materials from any designatedprocessing site:

(1)

The Secretary shall carry out a monitoring program adequate to l

(a)

The concentration of radium-226 define the extent of ground-water in land averaged over any area of contamination by listed constitu-I i

100 square meters shall not ents.from residual radioactive l

exceed the background level by materials and to monitor more than -

compliance with this Subpart.

(1) 5 pCi/g, averaged over the first 15 (2)

The Secretary may propose and, cm of soil below the surface, and with the Commission's concurrence, apply altern-tive (2) 15 pCi/g, averaged over 15 cm concentration limits provioed that, thick layers of soil more than 15 after considering practicable cm below the surface, corrective actions, the Commission determines that these (b)

In any occupied or habitable are as low as reasonably achiev-building -

able, and 6264.94(b) is satisfied.

(1) The objective of remedial action (3)

The functions and responsibilities shall be, and reasonable effort designated in referenced shall be made to achieve, an an-paragraphs of Part 264 of this nual average (or equivalent) radon chapter as those of the " Regional decay product concentration Administrator" with respect to (including background) not to

" facility permits" shall be carried exceed 0.02 WL. In any case, the out by the Commission.

radon decay product ' concentration (including background) shall not (4)

The remedial period established exceed 0.03 WL, and under Subpart A may be extended by an amount not to exceed 100 (2) The level of gamma radiation shall years if:

not exceed the background level by more than 20 miroroentgens (i)

The concentration limits es-tablished under this Subpart per hour.

3re not projected to be ex-(c)

The concentration of any listed coeded at the end of this constituent in ground water as a extended remedial period.

result of releases from residual radioactive material at any desig-(ii)

Institutional controls, which

= = 22.1883 r u sar.nrvaion i D.8 l

l l

l

~-

I l

1 i

Page 9

\\

k 40 CFR 192; Sept. 24,1987 NMSSILLUR Ref. Doc.

1

" reasonable assurance" that the provi-l l

sions of Subparts A and B are satisfied.

i will effectively protect public This should be done as appropriate health and satisfy beneficial uses through use of analytical models and site-j of ground water during the extend-specific analyses, in the case of Subpart l

ed remedial period, is instituted, as

}

part of the remedial action at the A, and for Subpart 8, through measure-ments performed within the accuracy of processing site and wherever con-currently available types of field and labo-4 l

tamination by listed constituents ratory instruments in conjunction with from residual radioactive materials reasonable survey and sampling proco-j is found in ground water, or is pro-dures. These methods and procedures jocted to be found.

may be varied to suit conditions at j

l (iii) The ground water is not currently specific sites, in particular:

or projected to become a source of supply for public drinking water (a)(1) The purpose of Subpart A is to provide long-term stabilization and subject to provisions of the Safe isolation in order to inhibit misuse Drinking Water Act during the and spreading of residual radio-extended remedial period, and active materials, control releases of radon to air and protect water.

(iv) The requirements of Subpart A are Subpart A may be implemented satisfied within the time frame es-tablished under Section 112(a) of through analysis of the physical the Act, or as extended by Act of properties of the site and the control system and projection of Congress.

the effects of natural processes soo a m s. m s - - sa m a m m w w 24 over time. Events and processes that could significantly affect the average redon release rate from Subpart C - Implementation the entire disposal site should be i

considered. Phenomena that are localized or temporary, such as i 192.20 Guidance for implementation local cracking or burrowing of

' d*""'

Section 108 of the Act requires the account only if their cumulative Secretary of Energy to select and perform effect would be segru,ficant m remedial actions with the concurrence of detennnno can$ame wh h the Nuclear Regulatory Commission and the full participation of any State that theories, and prevalent expert jud-pays part of the cost and.in consultation, gement may be used to decide as appropriate, with affected Indian that a control system will satisfy Tribes and the Secretary of the Interior.

the standard. The numerical range These parties, m, their respective roles un-provided in the standard for the der Section 108, are referred to hereafter vity of th effuties of as "the implementing agencies. The the control of residual radioactive implementing agencies shall establish m-erid dio for consideration ethods and procedures to provide of various factors affecting the Juaa 22. ma D9 F#4AL SM. HEVtS60N 1

Page 10 i

40 CFR 192; Sept. 24,1987 NMSSILLUR Ref. Doc.

abraston of the cover, and i

longevity of control and accommooate settling and stabilization methods and their l

subsidence so that the cov-costs. These factors have er's integrity is maintained.

different levels of predictability and may vary for different sites.

(b)(1) Compliance with 1192.12(a) and (b) of Subpart B, to the extent (2) Protection of water should be con-practical, should be demonstrated sidered on a case-by-case basis, through radiation surveys. Such drawing on hydrological and geo-surveys may, if appropriate, be re-chemical surveys and all other stricted to locations likely to con-relevant data. The hydrologic and tain residual radioactive materials.

geologic assessment to be cond-These surveys should be designed ucted at sach site shall include a for compliance averaged over monitoring program sufficient to limited areas rather than point by-establish background ground-water point compliance of the standards.

quality through one or more up-in most cases, measurements of gradient wells. New disposal sites for tailings that still contain water gamma radiation exposure rates above and below the land surfc:e at greater than tt.a level of can be used to show compliance

" specific retention" or tailings that with 5192.12(a). Protocols for are slurried to the new location making such measurements should shall use a liner or equivalent to be based on assuming realistic prevent contamination of ground radium distributions near the j

water.

surface rather than extremes rarely encountered.

(3) The remedial action plan, receiving approval by the Commission, shall (b)(2) in l192.12(a), " background level" j

specify how applicable require-refees to native radium concentra-monts of Subpart A are to be tion in soil. Since this may not be satisfied. The plan shallinclude determinable in the presence of the schedule and steps necessary contamination by residual radioac-to complete disposal operations at tive materials, a surrogate the site. It shallinclude an es-

" background level" may be timate of the inventory of wastes established by simple direct or in-to be disposed of in the pile and direct (e.g., gamma radiation) their listed constituents and measurements portormed nearby address (i) any need to eliminate but outside the contaminated loca-free liquids: (ii) stabilization of tion.

wastes to a bearing capacity suf-ficient to support the final cover; and (iii) the design and (b)(3) Compliance with 6192.12(b) may be demonstrated by methods that construction of a cover to manage the Department of Energy has ap-the migration of liquids through proved for use under Pub. L. 92-the stabilized pile, function with 314 (10 CFR 712), or by other minimum maintenance, promote methods that the implementing drainage and minimize erosion or w 22. m 3 D.1 O F#dAL SRP. MEVMeON 1

l 40 CFR 192; Sept. 24,1987 NMSSILLUR Ref. Doc.

Page 11 agencies determine are adequate.

to be used for cleanup of ground Residual radioactive materials water.

should be removed from buildings exceeding 0.03 WL so that future

(""**5'"'""**"*""*"

replacement buildings will not pose a hazard (unless removal is not practical - see 5192.21 (c)).

I 192.21 Criteria for applying supple-However, sealants, filtration, and mental standards ventilation devices may provide reasonable assurance of reductions Unless otherwise indicated in this from 0.03 WL to below 0.02 WL.

subpart, all terms shall have the same in unusual cases, indoor radiation meaning as defined in Title 1 of the Act or may exceed the levels specified in in Subparts A and B. The implementing 5192.12(b) due to sources other agencies may (and in the case of than residual radioactive materials.

Subsection (h) shall) apply standards un-Remedial actions are not required der $192.22 in lieu of the standards of in nrder to comply with the stan-Subparts A or B if they determine that dard when there is reasonable any of the following circumstances ex-assurance that residual radioactive ists:

materials are not the cause of such excess.

(a)

Remedial actions required to satisfy Subparts A or B would (4) The remedial action plan, pose a clear risk of injury to following approval by the Commis-workers or to members of the sion, will specify how applicable public, notwithstanding reasonable i

requirements of Subpart B would be measures to avoid or reduce risk.

satisfied. The plan should include the schedule and steps necessary to (b)

Remedial actions to satisfy the complete the cleanup of ground water cleanup standards for land, at the site. It should document the 6192.12(a) and (c), or the extent of contamination due to re-acquisition of minimum materials leases prior to final disposal, including required for control to satisfy the identification and location of listed t192.02(a)(2) and (3), would, not-constituents and the rate and direc-w thstanding reasonable measures tion of movement of contaminated to limit damage, directly produce ground water. In addition, the assess

environmental harm that is clearly ment should consider future plume excessive compared to the health movement, including an evaluation of benefits to persons living on or such processes as attenuation and near the site, now or in the future, dilution. In cases where A clear excess of environmental 6192.12(c)(4) is invoked, the plan harm is harm that is long-term, should include a monitoring program manifest, and grossly to verify projections of plume move-disproportionate to health ment and attenuation throughout the benefits that may be remedial period. Finally, the plan reasonably by anticipated, should specify details of the method d""" " *

rwt sar. nevneow i D-11

40 CFR 192; Sept. 24,1987 NMSSILLUR Ref. Doc.

P1go 12 (c)

The estimated cost of remedial construction at the site,

~

and the applicability of less action to satisfy 1192.12(a) at a

" vicinity" site (described under costly remedial methods than removal of residual ra-Section 101(6)(B) of the Act) is dioactive materials.

unreasonably high relative to long-l term benefits, and the residual There is no known remedial action.

radioactive materials do not pose a te) clear presence of future hazard.

The likelihood that buildings will be (f)

The restoration of ground water j

erected or that people will spend quality at any designated process-j long periods of time at such a vi-ing site under 5192.12(c) is cinity site should be considered in technically impracticable from an j

evaluating this hazard. Remedial engineering perspective.

1 action will generally not be nec-i essary where residual radioactive (g)

The ground water is Class 111.

materials have been placed semi-l permanently in a location where (h)

Radionuclides other than radi-site-specific factors limit their um---226 and its decay products hazard and from which they are are present in sufficient quantity and concentration to constitute a costly or difficult to remove, or where only minor quantities of re-significant radiation hazard from sidual radioactive materials are residual radioactive materials.

involved. Examples are residual I"

5"

5 'n3 -*, sa m mm se-24 radioactive materials under hard surface public roads and side-walks, around public sewer lines, or in fence post foundations. Sup-5 192.22 Supplemental standards plemental standards should not be applied at such sites; however, if Federal agencies implementing individuals are likely to be exposed Subparts A and 8 may in lieu thereof pro-for long periods of time to coed pursuant to this section with radiation from such materials at respect to generic or individual situations levels above those that prevail meeting this eligibility requirements of under 1192.12(a).

1192.21.

(d)

The cost of a remedial action for (a)

When one or more of the criteria cleanup of a building under 519-of 1192.21(a) through (g) applies, 7.12(b) is clearly unreasonably the implementing agencies shall nigh relative to the benefits. Fac-select and perform actions that tors that should be included in this come as close to meeting i

judgement are the anticipated the otherwise applicable period of occupancy, the incro-standard as is reasonable mental radiation level that would under the circumstances.

be affected by the remedial action, the residual useful lifetime of the (b)

When 1192.21(h) applies, building, the potential for future w 22. ma D 12 FINAL SRP. MrVIS80N 1

40 CFR 192; Sept. 24,1987 NMSSILLUR Ref. Doc.

Page 13 remedial actions shall, in addition to i 192.23 Effective date satisfying the standards of Subparts A and B, reduce other residual radio-Subparts A,B, and C shall be effective activity to levels as low as reasonably March 7,1983.

achievable.

(c)

The implementing agencies may make general determinations concerning remsdial actions under 40 CFR 192.20(a)(2) and (3) were this Section that will apply to all remanded by Tenth Circuit Court j

locations with specified character-of Appeals on September 3,1985.

istics, or they may make a determination for a specific loca-Proposed rule was published in the tion. When remedial actions are Federal Register on September 24, proposed under this Section for a 1987.

specific location, the Department of Energy shallinform any private owners and occupants of the affectad 'scation and solicit their comments. The Department of Energy shall provide any such comments to the other implementing agencies. The De-partment of Energy shall also pe-riodically inform the Environmental Protection Agency of both general and individual determinations un-der the provisions of this Section.

(d)

When 5192.21(f) or (g) applies, implementing agencies must apply any remedial actions for the restoration of contaminated ground water that is required to.

assure, at a minimum, protection of human health and the environ-ment.

ne m soo a s. sees a sa m seooo s.w 24 1ee71 w 22,issa D 13 FINAL SRP. REVisK)N 1

P:go 14 40 CFR 192; Sept. 24,1987 NMSSILLUR Ref. Doc.

DOE and NRC agreed (DOE-NRC MOU, Nov. 6,1990) to use proposed EPA standards (52 FR 36000, September 24,1987) on an interim basis and will use the Final EPA Standards when promul-gated.

Final Rule drafted May 6,1991; currendy in review at OMB.

Document Print Date:

June 23,1993

u. 22. s on D.14 roen sae. nevmoe i

. _ _. _. _. _... _ _ _. _ _ _. _ _ - _ _.. _ - _ -. _ _ _ _ - _. _ _ _ -... _. _.. _. ~... _ _ _. _. _.

L E d - 91 h

I' i. Il,-

RAE-9-4 i

U.S. DEPARTMENT OF ENERGY AN IENT S0Il M0!STURES IN WESTERN URANIUM MILLING REGIONS Draft Report Prepared for Battelle Pacific Northwest Laboratory Richland Washington Under Subcontract B-A5527-A-P Septembe r,1981 by V.C. Rogers K.K. Nielson D.C. Rich Rogers & Associates Engineering Corporation 515 East 4500 South Suite G-100 Salt Lake City, Utah 84107

~

~.

The above considerations lead to the following functional form for the correlation:

i (1) f 2

[

M = A f(P) + A f(E) + A f(S) 7 2

3 ambient soil moisture (dry wt. percent) f where M

=

j annual precipitation P

=

l annual lake evaporation E

=

soil type S

=

4 Values for P and E were obtained from Reference 10 i

The general functions in Eq (1) were represented by power functions so l

that M is represented by P + A E" + A (2)

M=A y 2

3 A satisfactory fit to the data was obtained for m equal 0.5, n equal unity, 4

and A, A ' ""d # assigned values so that

+

y y

2 3

M = 3.1P - 0.03E f) S,

( 3) i where soil moistum (dry wt. percent)

M

=

annual precipitation (in) f P

=

annual lake evaporation (in)

E

=

i 4

soil index S

=

1 J

2.9 for clay

=

1

-1.0 for sand

=

1 Equation 3 is given as the two curves in Figure 9.

i Other representations for the soil loss thrm were used in the correlation.

)

l h

namely annual average daily temperature and annual heating degree days, but they I

did not provide as good a fit to the data as did the annual lake evaporation.

I I

i 23

I D Cla uq 4

UNITED STATES y=

NUCLEAR REGULATORY COMMISSION f

WASHiNOToN, D.C. 2056M001

\\,...../

NRC INSPECTION MANUAL ttuR MANUAL CHAPTER 2801 11e.(2) BYPRODUCT MATERIAL DISPOSAL SITE i

AND FACILITY INSPECTION PROGRAM 2801-01 PURPOSE This chapter establishes the safety inspection program for 11e.(2) byproduct material disposal sites and facilities (11e.(2) sites) licensed and regulated under 10 CFR Part 40. These sites include both commercial disposal facilities and sites associated with licensed uranium mills.

Included in the program are i

inspection procedures related to all phases of activities at 11e.(2) sites:

construction, pre-operations, operations, and reclamation. Procedures presented cover those facilities licensed and regulated in their entirety by NRC.

The primary purpose of the inspection program is to obtain sufficient information through observations, personnel interviews, independent measurements, and review of facility records and procedures to ascertain in a timely manner whether facility operations, and radiological and non-radiological programs are in conformance with regulatory requirements and the conditions of the applicable license.

As a result the inspection program determines that 11e.(2) sites are managed throughout their entire life cycle in a manner that provides protection from radioactivity to employees, members of the public, and the environment.

2801-02 OBJECTIVES 02.01 To establish general policy and priorities for the inspection of 11e.(2) byproduct material disposal sites.

02.02 To establish a uniform process for the inspection of 11e.(2) byproduct material disposal sites.

02.03 To define specific requirements for inspection of 11e.(2) byproduct material disposal sites.

2801-03 DEFINITIONS 03.01 11e.(2) Bvoroduct Material, as defined in the Atomic Energy Act of 1954, as amended, means tailings or waste produced by the extraction of uranium or thorium from any ore processed primarily for its source material content.

Issue Date: 04/15/94 2801

?

2801-04 PROGRAM APPLICABILITY This program has been developed to respond to existing and developing needs for inspection procedures related to construction, pre-operation, operations, and reclamation for sites licensed by NRC. Where 11e.(2) byproduct material disposal sites are operating under Agreement State regulation, it is expected that responsibility for regulation and inspection activities at those sites will continue to reside with the Agreement States.

It is noted that existing inspection procedures from other NRC programs can be applied, in full or in part, to many aspects of 11e.(2) byproduct material disposal site inspections, and that additional inspection procedures specific to disposal technology and on-site activity can be developed and employed incrementally, as needed. Tables 1 and 2 provides a listing of procedures that are either currently available or in preparation, and includes comments concerning their applicability. Minimum and normal frequencies of inspection are listed; adoption of the minimum frequency i

l of inspection should be tailored to both the level of disposal activity and to the performance of the licensee.

2801-05 PROGRAM DESCRIPTION l

05.01 General. The lle.(2) byproduct material disposal site inspection program i

has been divided into three parts.

The parts are designed to be responsive to i

the various inspection needs during the different phases of disposal facility l

life: construction / pre-operations, operations, and reclamation. Each phase of i

the inspection program varies with respect to applicable inspection procedures, l

inspection frequency, and degree to which a given procedure may be applied. The inspection programs for each phase are discussed in narrative form in Section 2801-08. Tables 1 and 2 present information for the construction / pre-operations, operations and reclamation phases.

05.02 Adiustments.

The program provides regional offices the flexibility to adjust the frequencies of inspections within the various program areas based on an evaluation of the inspection findings and enforcement experience with a particular licensee. Alternate frequencies of inspection for various procedures are specified in Tables 1 and 2.

The lower frequency specified is the minimum frequency to which the inspection may be reduced by the regional office.

The higher frequency of inspection specified for the procedure shall be the normal inspection frequency for the program.

There is no maximum frequency expressed in Tables 1 and 2.

It is expected that any level of effort (i.e., frequency of inspection) above that specified as the normal frequency would be established at a level commensurate with whatever is needed to resolve identified problems and their importance to safety.

l 2801-06 REVIEW 0F EVENTS All inspections should include, as appropriate, a review of licensee reportable and non-reportable events that involve contamination, releases, equipment malfunctions, or other similar events that have generic significance. The review should cover corrective a:tions taken by the licensee and follow-up actions taken to prevent recurrence.

Non-reportable events should continue to be examined during inspections, to determine appropriate corrective actions or follow-up: these events may involve safety issues that should be followed up by the Occupational Safety and Health 2801 Issue Date: 04/15/94

Ad2inistration, Mine Safety and Health Administration, and existing or potential operational difficulties not otherwise reportable, such as bio-intrusion in disposal units, erosion or sloughing of trench walls, or uncontrolled wind erosion. Additional guidance on non-reportable events is contained in individual inspection procedures.

2801-07 REGIONAL RESPONSIBILITY FOR LICENSEES The responsibility for inspection resides with the regional office in which the licensee operation is located.

For efficiency in resource use, the regional office may request another regional office or Headquarters to assist in the conduct of inspections when specialized technical expertise is needed and is not available within the responsible region.

In some cases, a region may wish to transfer all or part of the inspection responsibility to another region or to Headquarters. These arrangements may be made with mutual agreement between the offices involved. If a permanent transfer of total inspection responsibility is involved, the affected regional offices should ensure that the appropriate changes are made to the computerized license data file by informing the Office of Nuclear Material Safety and Safeguards (NMSS) of the change in inspection responsibility for the license and requesting a change in the file. The regional office assuming inspection responsibility will be credited with the caseload in budgeting and allocating resources.

2801-08 INSPECTION DURING VARIOUS PHASES OF FACILITY LIFE 08.01 Part I - Insoection Durina the Construction and Pre-Operational Phase a.

Purpose The purpose of this instruction is to provide guidance for planning and conducting inspections during the construction / pre-operations phase of facility life.

Activities encompassed during the construction / pre-operations phase include disposal trench construction, liner placement, observation and verification of placement and compaction of cover materials, equipment use, and compliance with applicable construction specifications requirements in accordance with applicable management controls and quality assurance procedures, b.

Imolementation This inspection program begins upon issuance of the license and continues until the site begins active receipt and disposal of waste.

Situations may arise in which inspection requirements specified for other phases may apply concurrently with those specified here for the pre-operational phase. For example, certain requirements contained under Parts I and 11 may apply in the construction, pre-operational checks, and startup of a major modification to the site.

The lle.(2) byproduct material disposal site pre-operational inspection program is defined by selection from among the list of procedures in Table 1.

The areas covered during an inspection need not be limited only to those elements discussed in the procedures, but may need to include examination of other activities not expressly delineated or covered in existing procedures.

In such cases, the inspector must exercise good professional judgment in modifying the inspection and in identifying to Issue Date: 04/15/94 2801

the prograa office the possible need for development of supplemental l

guidance. Conformance with the principles of ALARA should be a principal concern at all times.

For the normal inspection frequency, each procedure should be completed for each specific frequency, regardless of the number of inspection visits required for completion.

In practice, part or all of the procedure element may need to be examined during each inspection visit.

Emphasis should be placed on physical examinations, observation of conduct of i._

operations, independent measurements, and personnel interviews. Attention should be directed toward the availability of written procedures, the degree to which they are being followed, and the state of training of on-site personnel. When necessary, effort should be concentrated on areas l

of perceived concern. Review of records should otherwise involve only a sampling of those records important to safety of personnel and the general public. For example, if the organizational structure has not changed with j

respect to personnel and assigned functions and responsibilities, the 4

inspector should not pursue the subject of organization in any detail, unless there is reason to believe that such is not the case. Discretion i

in such areas is left to the judgement of the inspector.

c.

Reaulatory Considerations The inspector should be especially familiar with current license i

requirements; previous inspection reports; applicable codes, standards and guides; and the following regulations:

10 CFR Part 19 Notices, Instructions, and Reports to Workers: Inspection and Investigations 10 CFR Part 20 Standards for Protection against Radiation 10 CFR Part 21 Reporting of Defects and Noncompliance 10 CFR Part 40 Domestic Licensing of Source Material 10 CFR Part 61.82 Commission Inspection of Land Disposal Facilities (Commercial Disposal Only) d.

Guidance for Use of Inspection Procedures Durina the Pre-Onerational Phase The inspection procedures indicated in Table 1 (enclosed) for the construction / pre-operations phase are applicable to inspections conducted at lle.(2) byproduct material disposal sites during construction / pre-operations. The inspection staff can determine the applicable elements of each procedure by reviewing the procedure, the facility license, and reports of previous inspections.

08.02 Part II - Insoection Durina the Operations Phase a.

Purpose The purpose of this instruction is to provide guidance for planning and conducting inspections during the operations phase of facility life.

Activities encompassed during the operations phase include receipt and handling of incoming lle.(2) byproduct material, emplacement of the 2801 Issue Date: 04/15/94

11e.(2) byproduct material for dis' posal, radiation safety and environ-t mental monitoring activities, and records management.

I b.

Imolementation i

This inspection program begins upon issuance of the facility license and continues until the facility ceases active receipt and/or disposal of waste.

Situations may arise in which inspection requirements specified for other phases may apply concurrently with those specified here for the operations phase. For example, certain requirements contained under Parts I and III may apply in the operations or startup of a major modification to the facility.

The lle.(2) byproduct material disposal site operations inspection program is defined by selection from among the list of procedures in Table 2.

The i

areas covered during an inspection need not be limited only to those elements discussed in the procedures, but may need to include examination of other activities not expressly delineated or covered in existing procedures. In such cases, the inspector must exercise good professional j

judgment in modifying the inspection and in identifying to the program t

office the possible need for development of supplemental guidance.

Conformance with the principles of ALARA should be a principal concern at i

all times.

i i

For the normal inspection frequency, each procedure should be completed

)

for each specific frequency, regardless of the number of inspection visits required for completion.

In practice, part or all of the procedure j

element may need to be examined during each inspection visit.

Emphasis should be placed on physical examinations, observation of conduct of operations, independent measurements, and personnel interviews. Attention

+

should be directed toward the availability of written procedures, the degree to which they are being followed, _ and the state of training of j

on-site personnel. When necessary, effort should be concentrated on areas i

of parceived concern. Review of records should otherwise involve only a

{

san.pling of those records important to safety of personnel and the general public. For example, if the organizational structure has not changed with respect to personnel and assigned functions and responsibilities, the inspector should not pursue the subject of organization in any detail, 1

unless there is reason to believe that such is not the case. Discretion i

in such areas is left to the judgement of the inspector.

i 1

c.

Reaulatory Considerations i

The inspector should be especially familiar with current license requirements; previous inspection reports; applicable codes, standards and guides; and the following regulations:

l 10 CFR Part 19 Notices, Instructions, and Reports to i.

Workers: Inspection and Investigations i

10 CFR Part 20 Standards for Protection against Radiation

}

10 CFR Part 21 Reporting of Defects and Noncompliance 10 CFR Part 40 Domestic Licensing of Source Material 1

10 CFR Part 61.80 Maintenance of Records, Reports, and Transfers Issue Date: 04/15/94 2801

~

10 CFR Part 61.82 Commission Inspection of Land Disposal l

Facilities (Commercial Disposal Only) 1 d.

Guidance for Use of Insoection Procedures Durina Operations i

~

The inspection procedures indicated in Table 2 (enclosed) for the j

Operations Phase are applicable to inspections conducted at lle.(2) byproduct material disposal sites, including mills authorized for disposal of in situ leach facility waste and other lle.(2) byproduct material, during operations.

The inspection staff can determine the applicable i

elements of each procedure by reviewing the procedure, the facility

[

license, and reports of previous inspections.

i l

'08.03 Part III - Inspection Durina the Reclamation and Decommissionina Phase

]

a.

Purnose The purpose of this instruction is to provide guidance for planning and conducting inspections during the period of reclamation of a lle.(2) byproduct material disposal site. The term " reclamation," as used herein, encompasses those activities that must be carried out by the licensee after the cessation of waste receipt and/or disposal operations, to allow the Commission to formally terminate the license and the licensee to transfer ownership of the land to the U.S. Department of Energy in accordance with 10 CFR Part 40.28. In some cases, as specifically allowed or required by license condition, some closure activities may occur for some parts of a facility during the operations phase.

b.

Imolementation This program is initiated when the licensee begins implementation of any portion of the approved reclamation plan. The foundation for planning and scheduling inspections will thus be the reclamation plan.

The criteria for inspections will be license conditions and applicable regulations some of which will directly address reclamation activities.

In many cases, portions of the reclamation plan may be implemented for part of a site while active operations continue elsewhere on site.

In these cases, the appropriate portions of this program shoeld be implemented in conjunction with the operations inspection program. The reclamation plan itself, as amended during site operation and approved by the NRC, should be reviewed by the regional office to determine if procedural or scheduling modifications are necessary to enable planning of an efficient inspection program.

The inspection program continues in effect until the licensee has implemented all elements of the reclamation plan, the license is terminated, and the title to the land is transferred to the U.S.

Department of Energy for long-term surveillance and maintenance.

The lle.(2) byproduct material disposal site or uranium mill reclamation and decommissioning inspection program is also defined by selection from among the list of procedures in Table 2.

The areas covered during an inspection need not be limited only to those elements discussed in the procedures, but may need to include examination of other activities not expressly delineated or covered in existing procedures.

In such cases, the inspector must exercise good professional judgment in modifying the inspection and in identifying to the program office the possible need for 2801 Issue Date: 04/15/94

development of supplGmental guidance. Conformance with the principles of ALARA should be a principal concern at all times.

For the normal inspection frequency, each procedure should be completed for each specific frequency, regardless of the number of inspection visits required for completion.

In practice, part or all of the procedure element may need to be examined during each inspection visit.

Emphasis should be placed on physical examinations, observation of conduct of operations, independent measurements, and personnel interviews. Attention should be directed toward the availability of written procedures, the degree to which they are being followed, and the state of training of on-site personnel. When necessary, effort should be concentrated on areas of perceived concern. Review of records should otherwise involve only a sampling of those records important to safety of personnel and the general public. For example, if the organizational structure has not changed with 1

respect to personnel and assigned functions and responsibilities, the inspector should not pursue the subject of organization in any detail, unless there is reason to believe that such is not the case. Discretion in such areas is left to the judgement of the inspector.

c.

Reaulatory Considerations The inspector should be especially familiar with current license requirements; previous inspection reports; applicable codes, standards and guides; and the following regulations:

10 CFR Part 20 Standards for Protection against Radiation 10 CFR Part 40 Domestic Licensing of Source Material 10 CFR Part 61.82 Commission Inspection of Land Disposal Facilities (Commercial Disposal Only) d.

Guidance for Use of Inspection Procedures Durina Reclamation and Decommissionina The inspection procedures indicated in Table 2 (enclosed) are applicable (as noted in comments) to inspections conducted at 11e.(2) byproduct material disposal sites or uranium mills during closure. The inspection staff can determine the applicable elements of each procedure by reviewing the procedure, the facility license, and the licensee's closure plan.

END Tables:

Table 1, Inspection Procedures Applicable to Pre-Operational Inspection of An lle.(2) Byproduct Material Disposal Site Table 2, Inspection Procedures Applicable to Inspection of An 11e.(2)

Byproduct Material Disposal Site During Operations and Closure Issue Date: 04/15/94 2801

TABLE 1 INSPECTION PROCEDURES APPLICA8LE TO PRE-OPERATIONAL INSPECil0N OF AN 110.G) SYPRODUCT MATERIAL DISPOSAL SITE Procedures Proce&re Title insoection Freauency Anoticability of Proce & re to N&r Min.

Normat Insoection of 11e.(2) SVDroduct Materiet Disposet Ete 4

30703 Management Each Each Inspectors should stbscribe *o the Entrance / Exit Interview Inspection Inspection general principles established in this proce&re.

36100 10 CFR Part 21 As As Inspectors should be sensitive to the Inspection at Nuclear Necessary Necessary underlying principle driving this Power Reactors procedure as it pertains to 11e.(2) disposal facilities.

1 88025 Survelliance Annual Twice per The concepts presented in this Testing year procedure are applicable to 11e.(2) disposal site operations. The license applicattor. and license conditions l

witt address the different systems j

encountered at a LLW disposat i

facility.

J l

l 1

J l

88045 Environmental Annual Twice per This procedure fu applicable in its l

Protection year entirety to the inspection of 11e.(2) disposal sites. Furthermore, specific j

guidance regarding its iglementation at such facilities is needed.

4 I

1 License conditions will specify offsite monitoring and sampling j

locations, frequencies, and applicable i

limits on levels and concentrations of 1

radioactivity.

1 88005 Management organization Annual Twice per inspector should athscribe to the and Construction year general principals estabtished in this procedure.

I I

4 4

Issue Date: 04/15/94 T1-1 2801, Table 1 i

TABLE 1 - INSPECTION PROCEDURES APPLICABLE TO PRE-OPERATIONAL INSPECil0N OF AN 110.(2) BYPRODUCV MATERIAL DISPOSAL SITE Procedures Procedure Title Inspection 'r_eqyency Acolicability of Procedure to Nu@er

Min, hseest inspection of 11e.(2) svoroduct faterial Discosal 3ite 88001 Construction Annual Key This procedure is applicable to the Review (MC2620, Appendix Construction inspection of engineering and A made into an IP) milestones -

construction aspects of a 11e.(2)

See Table 1 disposal f acility chring operations.

92701 Followup As As Generic Procedare applicable to Necessary Necessary 11e.(2) Disposal.

92702 Followup on Violetions/

As As Generic Procedure applicable to Deviations Necessary Necessary 11e.(2) Disposal.

92703 Confirmatory Action As As Generic Procedure applicable to Letters Necessary Necessary 11e.(2) Disposal.

93307 OSHA Interface As As Generic Procedure applicable to Activitles Necessary Necessary 11e.(2) Disposal, mm, #

l 2801, Table 1 T1 2 Issue Date: 04/15/94 l

URANIUM RECOVERY PROGRAM POLICY AND GUIDANCE DIRECTIVE LLWM 93-02 9

i STANDARD REVIEW PLAN FOR THE' REVIEW OF REMEDIAL ACTION OF INACTIVE MILL TAILINGS SITES UNDER TITLE I OF THE URANIUM MILL TAILINGS RADIATION CONTROL ACT Revision 1 June 1993 NSIBLE STA O

BY:

's aghsL JtS'~

n andra Wastler L John Sunneier, Chief,

_4,1 f

' q[ card Bangart, LLWM,5a 3 u

Darnet M. Gillen, LLUR REV EFFECTIVE UNTIL: 10/95

-)dyron Fliege UR Reevaluation Scheduled 6/95 LLWM 93-02 APPROVED: July 1,1993

-klO [b 7

\\

PURPOSE:

The Standard Review Plan (SRP) provides guidance to the NRC staff to assure that the review of DOE's Uranium Mill Tailings Remedial Action (UMTRA) Project documents are conducted in a thorough, focused, efficient, and consistent i

manner.

The SRP also assures that the staff's findings are properly documented.

In addition, the SRP provides DOE, impacted states, Indian tribes, and other interested parties, with an understanding of the review process.

i DISCUSSION:

The SRP allows for consistency between reviews and among reviewers in technical and regulatory matters related to the NRC review and concurrence in DOE's proposed remedial action at UNTRA sites. This is a revision to the SRP (formerly LLWM 92-09) to reflect comments by the Advisory Committee on Nuclear Waste.

In the absence of an SRP for Title II reclamation activities, this SRP should be used as guidance in that program to the extent practicable.

LIMITATIONS:

None PAGES IN REFERENCED DOCUNENT:

82, A-1, B-1, C-1 to C-4, and D-1 to D-15 BIBLIOGRAPHIC CITATION:

" Standard Review Plan for the Review of Remedial Action of Inactive Mill Tailings Sites Under Title I of the Uranium Mill Tailings Radiation Control Act," Revision 1, LLWM, June 1993.

RESPONSIBLE STAFF:

Sandra L. Wastler, LLUR, 301-504-2582 l

LLVVht 93-02 APPROVED: July 1,1993 PA

a 4

92-02

" Assessments and Audits: Low Level Waste Management (LLWM) Participation in Agreement State Reviews," LLWM, February 1992.

1 92-03

" Interim Guidance on Evaluation Procedure for Hydraulic Conductivity of Radon / Infiltration Barriers for Title I i

and Title II Mill Tailings Sites," Memorandum from J.J.

j Surmeier to R.E.

Hall, April 9, 1992.

92-04

" Guiding Principals for EPA-NRC Cooperation and Decisionmaking," March 1992.

92-05

" Air Sampling in the Workplace,"

Reg. Guide 8.25, Rev.

1, June 1992.

92-06

" Instructions for Recording and Reporting Occupational Radiation Exposure Data," Reg. Guide 8.7, Rev.1, June 1992.

92-07

" Radiation Dose to the Embryo / fetus," Reg. Guide 8.36, July 1992.

92-08

" Monitoring Criteria and Methods to Calculate Occupational Radiation Doses," Reg. Guide 8.34, July 1992.

92-09

" Standard Review Plan for UMTRCA Title I Mill Tailings Remedial Action Plans," Revision 1, LLWM, October, 1992.

SUPERSEDED BY 93-02.

92-10 "ALARA Levels For Effluents From Materials Facilities,"

Draft Reg. Guide DG-8013, October 1992.

93-01 "On-Site Construction Reviews of Remedial Action At Inactive Uranium Mill Tailings Sites,"

Chapter 2620, Inspection and Enforcement Manual, Rev.

1, February 1993.

" Standard Review Plan for the Review of Remedial Action 93-02 of Inactive Mill Tailings Sites Under Title I of the Uranium Mill Tailings Radiation Control Act," Rev.

1, June 1993.

LLWM-1 ISSUED: July 1,1993 Page 7

4 LLUR shall incorporate review comments when feasible and reasonable efforts shall be made to resolve the differences.

For comments not incorporated, the reasons for non-accameodation shall be discussed with the Director, URF0, and the Director, Division of Radiation Safety and Safeguards, and documented in a record to the file that will be transmitted to the parties involved.

A copy of this record to the file will be permanently retained by the LLUR directive syste' adian. (The LLUR directive system custodian will be des,..ted by the Chief, LLUR upon implementation of the UR Program Policy and Directive System.)

5.0 CnurneerurE For UR directives that have broader policy or legal implications, concurrence should be obtained from other NRC officas (e.g.,

Office of the General Council, Office of State Programs, Office of Enforcement, etc.) as appropriate. A concurrence block shall be provided on the Title cover for such concurrence.

6.0 APPROVALS OF UR DIRECTIVES The Director, LLWM shall review and approve all proposed new or revised UR directives.

l 7.0 DISTRIBUTION OF UR DIRECTIVES Upon approval by the Director LLWM, the UR directive will be transmitted to URF0 and LLUR for implementation. Additional distribution will be made to usual LLWM and NMSS files; to the Director, DRSS, in Region IV. A copy also will be provided to the Public Document Room and the Advisory Committee on Nuclear Waste.

The Table of Contents and Indexes for the UR Policy and Guidance Directive System will be distributed by memorandum to all URF0 and LLUR staff when changes or additions are made to the system. Any deleted directives from the system also will be identified in the above memorandum.

2.0 EFFECTIVE DATES OF Als REVISIONS TO UR OIRECTIVES 8.1 MR_pirectives.

The provisions of the initial set of UR strectives will go into effect on June 1, 1993.

All future UR directives will go into effect inmediately upon approval by the Director LLWM. When a specific effective date is necessary because of a management determination or to satisfy a legal or administrative requirement, the effective date must be specified in the UR directive.

LLWM-2 APPROVED: June 1,1993

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ML20134B841

Text

1.4 Evaluation Findings

2.4 Evaluation Findings

3.4 Evaluation Findings

0.1 Organk

4.4 Evaluation Findings

5.4 Evaluation Findings

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