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SAND84 -2242 * Unlimited Release * UC -70Printed January 1986

Nevada Nuclear Waste Storage Investigations Project

Retrievability: Strategy forCompliance Demonstration

. -

Richard J. Flores

Premared bySaiena National LaboratormesAlbuquorcus. Now Mxexco 87135 and Uvermore, California 94550or the United States OeDartmnint of Energyunder Contract OE.AC04-760P00769

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SAND84-2242

Unlimited releasePrinted January .986

NEVADA NUCLEAR WASTE STORAGE INVEST:GAT:ONS PROWECT

RETRIIVAB:LITY: STRATEGY FOR COMPLIANCE DEMONSTRATION

Richard J. FloresNNWSI Geotechnical Design Division

Sandia National LaboratoriesAlbuquerque, NM 87185

ABSTRACT

In accordance Vith the Nuclear Waste Policy Act (NWPA) OF 1932,Federal agencies have developed regulations to ensure :hazradioactive-waste disposal operations will not endanger the publichealth and safety or the environment. Included in these regulaticnsis the requirement to maintain, as an added measure of assurance, theoption to retrieve emplaced radioactive waste. Consequently, arepository design must include retrieval as a planned contingency.The Nevada Nuclear Waste Storage Investigations (NNWSI) project isinvestigating the feasib'lity of locating a repository for radioactivewaste disposal in the tuff formations at Yucca Mountain in southernNevada. he-tauga~ horizon is located in the unsaturated zone at anaverage ubsurfac)depth of, approximately, 300 m, in a formation ofwelded tuf*T emplacement options are currently being consideredfor the disposal of waste packages: horizontal and verticalconfigurations. In the vertical configuration, a single package isemplaced in a 7.6-n-deep vertical hole d-" led into the floor ofemplacement drifts. For the horizontal option, up to 34 wastepackages are emplaced in each horizontal borehole drilled into thewall of the emplacement drift. The horizontal boreholes are up to 2CC

long. Both options require unique equipment and operations rorac^-Ieving compliance with the retrievability requirement. This paperpresents the stategy which defines the activities required fordemonstrating compliance with the retrievability requirement. ansupport of this strategy, current regulatory requirements, repositoryand equipment designs, expected conditions, and scenario developmentmethods are discussed.

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CONTENTS

1.0 :NTRODUCT:ON

1.1 BACXGROUND'.2 R0POSE AND JUSTIFICATICN1.3 DEFINITIONS1.4 BASIC ASSUMPTIONS

2.0 REGULATORY REQUIREMENTS

2.1 REASONS FOR THE RETRIEVAL OPTION2.2 RETRIEVAL TIME CONSTRAINTS

2.2.1 Retrieval Option Period2.2.2 Retrieval Period

*2.3 BACKFILL CONSIDERATIONS2.4 ALLOWABLE WASTE RESIDUALS

3.0 CONCEPTUAL SYSTEM FOR EMPLACEMENT AND RETRIEVAL

3.1 WASTE PACKAGE3.2 VERTICAL EMPLACEMENT TECHNIQUE a

3.2.1 Repository Layout 33.2.2 Vertical Emplacement and Retrieval a

Equipment3.2.2.1 Borehole Components :33.2.2.2 Transporter Subsystem 3

3.3 HORIZONTAL EMPLACEMENT TECHNIQUE 633.3.1 Repository Layout a73.3.2 Horizontal Emplacement and Retrieval 1,

Equipment3.3.2.1 Borehole Components lo3.3.2.2 Transporter Subsystem 17

4.0 EXPECTED CONDITIONS 26

4.1 ROCK TEMPERATURE 264.2 RADIATION4.3 ROCK STABILITY Y44.4 AIR QUALITY4.5 SUMMARY

5.0 RETRIEVAL SCENARIO DEVELOPMENT ii

5.1 STANDARD RETRIEVAL 355.1.1 Pre-retrieval Assessment ?9

5.1.2 Waste-Package Removal 3a

iii

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5.2 RETRZEVAL UNDER ADVERSE CONDITIONS5.2.1 identificaticn of Adverse Conditions 40

-5.2.2 - Evaluation of Adverse Conditions5.2.3 Xdditional Retrieval Steps 4

6.0 STATEGY FOR COMPLIANCE DEMONSTRATION 43

6.1 FACILITY DESIGN CRITERIA .6.1.1 Surface Facility Design 46.1.2 Underground openings 436.1.3 Ventilation System Design 4

6.2 EQUIPMENT DEVELOPMENT 4A6.2.1 Equipment Development - Vertical Option ;1.6.2.2 Equipment Development - Horizontal Option .4

6.2.2.1 Borehole Drilling and Liner 45EmplaceDent

6.2.2.2 Emplacement and Retrieval ;3Equipment

6.2.2.3 Retrieval Backup Equipment 45

6.3 DEMONSTRATIONS 456.3.1 Proof-of-Concept Demonstrations 46

6.3.1.1 Borehole Drilling 466.3.1.2 Borehole Components 466.3.2.3 Turntable and Emplacement 47

Mechanism6.3-1.4 Retrieval Backup System 47

6.3.2 Prototvpe Demonstrations 476.3.3 In Situ Demonstrations 47

6.4 OPERATIONAL ACTIVITIES 476.4.1 Documentation .86.4.2 Drift Maintenance 486.4.3 Performance Verification Program 4a

6.4.3.1 Monitoring and Data Collection 496.4.3.2 Sample Collection 496.4.3.3 Waste Package Examination :9

6.5 RETRIEVAL SCENARIOS 49

6.6 SUPPCRTIVE STUDIES 506.6.1 Waste Characterization So6.6.2 Thermal Analyses ;G6.6.3 Rock Mechanics 506.6.4 Borehole-Liner Analysis 50

6.6.4.1 Failure Analysis 506.6.4.2 Potential Liner Enhancement .6

6.6.5 Radon Contamination S16.6.6 Monitoring System 52

6.7 QUALITY ASSURANCE PROGRAM 52

iv

7.0 SUMMARY

7. 17.27.3

-BASIC ASSUMPTIONSREGULATORY REQUIREMENTSCOMPLIANCE DEMONSTRATION

= -= -

REFERENCES

APPENDIX - APPLICABLE FEDERAL REGULATIONS

DISTRIBUTION LIST

5 7

v

FIG ES

Number Page

Retrieval Time Periods 3Retrieval Time Frame 'or Design Purposes ;Conceptual Waste Package 9Repository Layout for Vertical Emplacement of Waste

5 Typical Emplacement Panel for Vertical Emplacement :6 Vertical Emplacement Drift and Borehole 12

Configuration7 Design for Vertical Emplacement: Crushed-Tuff :

Backfi'l3 Design for Concept Vertical Emplacement: Shield Plug9 Preliminary Design of the Transporter for Vertical

Emplacementi0 Repository Layout for Horizontal Emplacement of Waste IS1: Typical Emplacement Panel for Horizontal 19

Configuration12 Empalcement Drift and Borehole Configuration 2013 Emplacement and Retrieval Equipment 21:4 Borehole Components for Horizontal Emplacement 22

Preliminary Conceptual Design of the Transporter for 23Horizontal EmplacementWaste Package and Dolly for Horizontal Emplacement 23

;7 Temperature of the Borehole Wall - Vertical 29Emplacement

13 Temperature of the Emplacement Drift - "ertical 30Emplacement

19 Temperature of the Access Drift - Vert-i-a' 3Emplacement

20 Temperature of the Borehole Wall - Horizontal 32Emplacement

21! Temperature of the Emplacement Drift - Horizontal 23Emplacement

22 interaction Between Design Process, Scenario 37Development and Supportive Studies

23 Standard Retrieval Steps 3324 Retrieval Steps 42

TABLE

i Thermal Analysis Data 27

vi

1.-.

1.0 iNTRCDUCTON

1.1 BACKGROUND

The U.S. Coftgress passed the Nuclear Waste Policy Act of 1982 (C'rPA/to provide the basic guidance, schedules, and source of funding forthe development of repositories for the disposal of radioactive wastein the United States. The Nevada Nuclear Waste Storage Investigations(NNWSI) project is one of three DOE projects evaluating sites for ttelocation of the first repository. The NNWSI project staff isi..nvestigating the feasibility of constructing a repository at YuccaMountain, which is located on and adjacent to the Nevada Test S.te(NTS), approximately 160 km northwest of Las Vegas, Nevada. Thedisposal concept involves emplacing packages of radioactive waste inthe tuff formations at Yucca Mountain. The target horizon Is aformation of welded tuff located in the unsaturated zone at an averag=subsurface depth of approximately 300 m.

In the past, scenarios for radioactive-waste disposal in geologicformations have featured vertical emplacement of the waste packages.In addition to vertical emplacement techniques, the NNWSI design grcu-at Sandia National Laboratories has chosen to consider the possibi: -,'of horizontal emplacement of the radioactive-waste packages in longboreholes. The horizontal technique offers various technical andoperational advantages and the potential for a substantial costsavings (Scully et al., 1984).

..2 PURPOSE AND JUSTIFICATION

Maintaining the option to retrieve emplaced waste packages is aperformance objective for the repository as established by the NuclearRegulatory Commission (NRC), (CFR, 1984). As such, compliance withthe requirement for retrievability must be verified. Thisverification must include technically sound analyses, tests, anddemonstrations. A logical, effective stategy is necessary fordirecting the activities required for compliance demonstration. Thestrategy emphasizes the need for the establishment of a credible database (e.g., results from analyses, design efforts, and demonstrations)to verify that all Federal regulations as well as NNWSI programobjectives, related to the retrievability requirement, are met.

1.3 DEFINITIONS

To aid in the interpretation of this document, the followingdefinitions of terms used in this document are provided:

Retrievabilitv Period - The time period for which theretrieval of the emplaced waste must be possible afterwaste-emplacement operations are initiated (termed First WasteEmplacement). Figure 1 provides a graphic illustration ofthe retrieval time periods.

- 1 -

Retrieval Option Period - The time period required forcompletion of a performance confirmation program and NuclearRegulatory Commisiion (NRC) review. During this period, theoption to retrieve the emplaced waste will be maintained.The start of this time period is First Waste Emplacement. 'rretrieval of the waste is not required, repository closure beginsafter the retrieval option period.

Retrieval Period - The time period required for removal ofthe emplaced waste from the underground repository, if adecision to retrieve the waste is made.

1.4 BASIC ASSUMPTIONS

The basic assumptions used for the development of this strategy are asfollows:

* The design of the repository at Yucca Mountain willincorporate the option to retrieve the emplaced waste asa planned contingency operation.

* The inclusion of the retrieval option will not compromisethe safety of the repository.

* Partial retrieval of the emplaced waste for economic,scientific, or performance confirmation purposes will notdegrade the effectiveness of the repository for containmentand isolation of waste, nor will it preclude the continuedemplacement of waste.

* The probability that total retrieval will be required, becauseof failure of the site to meet established performanceobjectives for the protection of the public and theenvironment, is extremely small.

-2-I... .

i

FIRST WASTEEMPLACEMENT

IRETRIEVAL OPTION PERIOD J RETRIEVAL PERIOD j-

w~

RETRIEVABILITY PERIOD uPI1

Figure 1. Retrieval Time Periods

2.0 REGUtATORY REQUIREMENTS

_n addition to the NWPA legislation passed by Congress, theEnvironmental ProtectionT Agency (EPA) and the Nuclear RegulatoryCommission (NRC) have established regulations concerning the rerrieva:of high-level radioactive waste from mined geologic repositories.These regulations are published in the Code of Federal Regulaticns(CFR); the EPA regulations applicable to retrieval are contaained in 40CFR 191 (CFR, 1985), and the NRC regulations are published in 10 CFR'0 (CFR, 1984). A listing of the major retrieval citations isincluded in the appendix.

The retrievability requirement affects the design and cost of therepository. The magnitude of the effect will vary according to thedegree of ease with which retrieval must be achieved and theduration of the retrieval option and retrieval periods. In order toevaluate the effect of the retrievability requirement on the NNWS:repository design, it is advantageous to identify the important pointsin tae regulations by categorizing them into four areas: (1) reasonsfor the retrieval option, (2) retrieval time constraints,%(3) backfi2.considerations, and (4) allowable waste residuals.

2.1 REASONS FOR THE R.ETREVAL OPTION

Identifying the reasons for which the retrievability requirement wasincluded in the regulations will assist in determining the appropr-azedesign emphasis to be placed on retrieval. In all of the regulations,the prir.cipal reason for the retrievability requirement is to ensurethe protection of the public and the environment. Furthermore, theNWPA provides for the recovery of spent fuel for its potential economicvalue. However, the NRC and EPA do not address the recovery of spentfuel for economic reasons; their primary concern is -zhe public healthand safety and the protection of the environment. Retrieval of somewaste packages as part of the performance confirmation program may ajsobe required.

2.2 RETRIEVAL TIME CONSTRAINTS

The time constraints addressed in the regulations fall into twocategories: the time limit for maintaining the option to retrieveemplaced waste (Retrieval Option Period) and the time limit forretrieval of the waste (Retrieval Period).

2.2. Retrieval Option Period

The references to the retrieval option period in the NWPA and 40 CFR191 are not specific. The NWPA refers to the retrieval option periodas an appropriate period to be specified by the Secretary of theDepartment of Energy (DOE). In 40 CFR 191.14(f) the time limit isdefined merely as a reasonable period of time after disposal. There

- 4 -

are two references to the retrieval option period in 10 CFR 60. -hefirst states that the option to retrieve must be maintained until aperformance confirmation program and NRC review have been completed.The other reference gives a specific time period, for design purmcses,of-50 years after waste emplacement has begun.

Because the references to the retrieval option period contained in 40CFR 191 and the NWPA are not specific, they are of little use fordesign input purposes. The two references in 10 CFR 60 are morespecific, and acknowledge that each repository must be dealt with onan individual basis. The first reference in 10 CFR 60 provides apractical and logical basis for determining an appropriate retrievaloption time limit. However, it is dependent upon the time requiredfor the completion of a performance confirmation program and the NRCreview. Studies completed at this time suggest that a performanceconfimation program could be completed within 5 to 10 years afterFirst Waste Emplacement (Wilems et al., 1980). An accurate estimateof the time required for NRC review is more difficult. The 50-yeardesign criterion, cited in the second reference in 10 CFR 60, isextemely conservative. However, to comply with the regulations, aretrieval option period of 50 years is proposed for design purposes.From an operational standpoint, the retrieval option period is dividedinto the operational and caretaker periods. The emplacement period isthe period during which the actual emplacement operations take place.During the caretaker period, repository monitoring and periodic driftinspection and maintenance will be performed. For design purposes, itis proposed that the emplacement and caretaker periods extend for 28and 22 years, respectively (DOE, 1984a).

2.2.2 Retrieval Period

The only discussion of the retrieval period is contained in 10 CFR 60.It describes the retrieval period time limit as about the same lengthof time required for construction of the repository and emplacement ofthe waste. For the NNWSI program, the present time estimates include 4years for the construction of the repository and 27 years for the wasteemplacement, or a total period of 31 years. However, for consistencywith the Generic Requirements Document, GRD, (DOE, 1984a), the timeperiods allocated in its Appendix B, (6 years for construction and 28years for emplacement) are proposed for design purposes. The totalretrieval period for design purposes is, therefore, 34 years.Combining the 50-year retrieval option period and the 34-year retrievalperiod, the proposed maximum retrievability period is 84 years fromFirst Waste Emplacement. This time scale is shown graphically inFigure 2.

2.3 BACKFILL CONSIDERATIONS

References to backfilling the drifts are contained in Subsection 2 of10 CFR 60.111(b). For the current design basis, there are no plansfor backfilling the drifts at the Yucca Mountain Repository before theend of the retrievability period.

-5-

A." .

FIRST WASTEEMPLACEMENT

RETRIEVAL OPTION , RETRIEVAL

RETRIEVABILITY MJ

I

84 YEARS V-1

EMPLACEMENT X CARETAKER I28 YEARS 'I 22 YEARS W1"I

Figure 2. Retrieval Time Frame for Design Purposes

2.4 ALLOWABLE WASTE RESIDUALS

Another major area that requires analysis and intermretation concernsthe possibility of a required retrieval due to failure of the site tomeet radionuclide containment requirements. In some cases it' m igt bebeneficial to leave some of the emplaced waste as long as the release-rate performance objectives are met. In 40 CFR 191.14(f) the ZPAaddresses this question by requiring that most of the waste can beremoved. In 10 CFR 60.111 the NRC states that the geologic repositoryoperations area shall be designed so that any or all of the emplacedwaste could be retrieved. It is important to note that the NRCreference applies to design criteria, whereas the EPA regulationapplies to the actual retrieval process.

12 �>

The NNWSI design will satisfy both regulations. The retrieval systemwill be designed so that any or all of the waste can be removed undernormal or anticipated adverse conditions. The probability of theoccurrence of an unanticipated event that would cause the repositoryto fail to meet the performance objectives and significantly affectthe ability to retrieve is extremely small. Should this unlikelysituation occur, it would be appropriate to analyze the mechanism thatcaused the retrieval decision. Because it is desirable to minimizethe potential hazards to the operating staff, the environment, and thegeneral public, it is possible that some of the waste could remain inthe repository as long as the radionuclide containment performanceobjectives outlined in 10 CFR 60 are met. In other words, it may beadvantageous to leave some of the waste in the repository in theunlikely event that a portion, or all of the repository, fails to meetthe established performance objectives. The decision would have to bebased upon the specific situation and would require sufficient proofthat the waste left in the repository would not exceed the containmentperformance requirements.

- 7 -

An-

3.0 CONCEPTtAL SYSTEM FOR EMPLACEMENT AND RETR:EVAL

3oth emplacement methods will utilize the waste package described inSection 3.1. The equipment for emplacement and retrieval operationsdiffers significantly for the two emplacement options underconsideration. Therefore, the descriptions of the emplacement andretrieval equipment for each configuration will be describedseparately. The design concepts presented here are based onconceptual equipment design information contained in the ReferenceInformation Base (RI3) at Sandia National Laboratories. As thedesigns evolve, the RIB will be updated to include the latest designinformation.

3.1 WASTE PACKAGE

An illustration of the waste package is presented in Figure 3. Thewaste package is currently undergoing extensive engineering analysisand design. However, the anticipated changes will, at most, onlyresult in an increase of the diameter by a few centimeters. Thiswould not affect the waste emplacement or retrieval concepts.

3.2 VERTICAL EMPLACEMENT TECHNIQUE

The current vertical emplacement concept involves emplacing a singleh-gh-level radioactive waste package into a vertical borehole drilled:nto the floor of the emplacement drift.

3.2.1 Repository Layout

The current repository layout for vertical emplacement, shown inFigure 4, includes ramp access between the surface and the undergroundfacilities for the transfer of radioactive waste packages and minedtuff. Access drifts are used to gain access to the emplacementdrifts. Illustrations of an emplacement panel layout and a typicalemplacement drift and borehole layout, are shown in Figures 5 and 6,respectively. A 6.7-m-high emplacement drift is required to orientthe cask vertically for emplacement and retrieval. As shown in Figure6, the emplacement boreholes are 7.6 m deep, which results in astandoff distance of 3.0 m. (The standoff distance is the shortestdistance between the waste package and the emplacement drift).

3.2.2 Emplacement and Retrieval Equipment - Vertical Option

The same equipment will be used for both emplacement and retrievaloperations. For simplicity, the descriptions of the equipment aredivided into two categories: (1) borehole components and

- a-

I

4.6 METERS

to

Figure 3. Conceptual Waste Package

WASTE TRANSPORT RAMP

TUFF-REMOVAL

RAMP

SHOP a

I

EMPLACEMENT EXHAUST SHAFT

EMPLACEMENT PANEL I

PERIMETER DRIFT

MAIN ACCESS DRIFTS

Figure 4. Repository Layout for Vertical Emplacement of Waste

LiIdi- STANDOFF TO MAIN ACCESS DRIFT

(60.8 METERS) STANDOFF TO PANEL ACCESS DRIFTC (23.7 METERS) I

0

EMPLACEMENT DRIFI PERIMETER DRIFT -

MAIN ACCESS DRIFTS MID PANEL ACCESS DRIFTI

UI

O N - - IIIIu - c zz c zI

V PANEL ACCESS DRIFTSL BARRIER PILLAR

Figure 5. Typical Emplacement Panel for Vertical Emplacement

4 -a

4 -,/. ,

\ -, -.

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~~~~~. \ .

..N ./ _ ~ _ _ _

_ _ _ _ , -_

/ / ' / x / s " '

SHIELD PLUG p

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WASTE PACKAGE xi-, _,,

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,., '.

6.7 METERS

7.6 METERS

Figure 6. Vertical Emplacement Drift and Borehole Configuration

- 12 -

(2) :ransporter subsystem. The borehole components include theborehole, the shielding collar, and any other items associated withthe borehole (e.g., backfill, partial liners, etc.). The transportersubsystem includes the transporter, the closure System, and associlaeauxiliary equipment. A complete description of the emplacement andretrieval equipment is contained in Stinebaugh, in preparation.

3.2.2.1 Borehole Components

There are currently two different designs under consideration for theborehole components subsystem for the vertical emplacementconfiguration (Stinebaugh, in preparation). The first concept, shownin Figure 7, involves backfilling in the space above the emplacedwaste package with crushed tuff. The borehole components include thecover, the support plate, the thimble, and crushed-tuft backfillmaterial. The backfill provides the necessary shielding between thewaste package and the emplacement drift. The second concept involvesthe use of a shield plug as shown in Figure 8. For this design, theborehole components include the borehole, the cover, the shield plug,a partial liner, crushed tuff, and the support plate. in this case,the function of the crushed tuff is to structurally stabilize thepartial liner. Shielding is provided by a shield plug. This methodoffers distinct retrieval advantages; however, it is potentially moreexpensive.

3.2.2.2 Transporter Subsystem

An illustration of the preliminary design of the transporter for thevertical emplacement and retrieval system is presented in Figure 9.Available hardware, commonly used in industry, will be incorporatedinto the design wherever possible, to reduce costs and ensurereliability of the transporter. The current transporter design forvertical concept incorporates a shielded cask into which the wastepackage is inserted. The cask is rotated to the vertical position fcemplacement or retrieval operations. Auxiliary equipment ±s requiresfor the emplacement and retrieval processes. The details of thefunctions of the auxiliary equipment are not relevant here. (SeeStinebaugh, in preparation, for further detail).

At the start of the emplacement operation, the waste package is load(on the transporter at the surface facility and carried to the properemplacement borehole. The cask is rotated to the vertical positionand aligned, and the waste package is lowered into the borehole.Then, either the shield plug, or crushed tuff backfill, is insertedinto the borehole through a shield collar with the use of auxiliaryequipment. Conceptually, the retrieval process is the reverse of th.emplacement process. This does not imply that the actual retrievalprocess is simply the reverse of the emplacement process. Asdiscussed in Section 5, Retrieval scenarios which consider standard

- 13 -

,."

LOCKING BAR

COVER

CRUSHED TUFF

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Figure 7. Concept for Vertical Emplacement: Crushed-Tuff Backfill

- 14 -

LOCKING BAR

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SUPPORT PLATE

Figure 8. Concept for Vertical Emplacement: Shield Plug

- is -

z

CASK

r- DIESEL GENERATORS

on

Figure 9. Preliminary Drawing of the Transporter for Vertical Emplacement of Waste

and potentially adverse conditions are being developed. In addit ^-,alternative retrieval methods are being developed (e.g., a stoutgrapple on the end of a drill pipe). In the extreme case, overcor:ngcould be used.

3.3 HORIZONTAL EMPLACEMENT TECHNIQUE

The current concept for the horizontal emplacement of high-levelradioactive waste involves the placement of up to 34 waste packagesinto horizontal boreholes up to 200 m long that are drilled into thesides of the emplacement drifts.

3.3.1 Repository Layout

The current repository layout for the horizontal emplacement conceptis shown in Figure 10. As with the vertical concept, ramps are Usedfor access between the surface and underground facilities. A typica.emplacement panel layout is presented in Figure 11. As shown inFigure 12, the waste emplacement boreholes are dr-lled into the wallsof the emplacement drifts. The current design calls for a 35-m-longstandoff distance. This distance was selected to limit the maximumdrift wall temperature to 500C for 50 years. The main differencebetween this layout and the one for the vertical concept is thereduced number of emplacement drifts and boreholes required foraccommodating the 70,000 MTU of high-level waste expected for disposa:at the repository.

3.3.2 Emplacement and Retrieval Equipment - Horizontal Option

For the horizontal emplacement concept, the same equipment will beused for both the emplacement and the retrieval operations. Theemplacement and retrieval system consists of two major subsystems:(1) the borehole components subsystem, which includes the borehole,the liner, and the closure system, and (2) the transporter subsystem,which includes the transporter, auxiliary equipment, and theemplacement dolly. An illustration of the complete emplacement andretrieval equipment is provided in Figure 13. For additionalinformation concerning the design of the emplacement and retrievalequipment, refer to White, in preparation.

3.3.2.1 Borehole Components

An illustration of the borehole components is presented in Figure !4.A liner will be emplaced in the borehole to ensure reliable access foremplacement and retrieval operations. The referer.ce material fzr theliner is a low carbon steel; however, the use of other materials isalso being considered. The possible use of grout between the linerand the borehole host rock is also being investigated. The closuresystem includes the collar and shielding closure that are mounted onthe drift wall and any shield plugs that might be required. The

- 17 -

i

a.

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A/ / r /\s ~~~~~EMPLACEMENT HORE I

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MAIN ACCESS DRAIFTS

Figure 10. Repository Layout for Horizontal Emplacement of Waste

STANDOFF TO MAIN ACCESS DRIFT(60.8 METERS)i

IG,I

DISTANCE BETWEEN BOREHOLESr (35 METERS)

STANDOFF TO PANEL ACCESS DRIFT(35 METERS)

EMPLACEMENT DRIFT

Figure 11. Typical Emplacement Panel for Horizontal Configuration

3 /

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Figure 12. Emplacement Drift and Borehole Configuration

WASTE PACKAGE / DOLLY

SHIELD CLOSURE

INTERFACE PLATE

CLOSURE DOOR

Figure 13. Emplacement and Retrieval Equipment

ENTRYLINER

FLANGE

INTERFACE PLATE

, HOUSING

GEARED MOTOR

DOLLY RELEASE CAM(IjIr1a

CASK GUIDE

Figure 14. Borehole Components for Horizontal Emplacement

iCASK

CLOSURE DOORDRIVE MOTORDIESEL

GENERATORS

TRANSPORTERCAB

1ta A

Figure 15. Preliminary Conceptual Design of the Transporter for Horizontal Emplacement

collar and closure provide shielding for the workers and fUn.ction asan accurate attachment mechanism for the transporter duringemplacement and retrieval. A shield plug, which is inser-ed byauxiliary equipment through the shielding collar, wi:l provideshielding for the workers after the shielding collar and closure havebeen removed.

3.3.2.2 Transporter Subsvstem

The transporter subsystem consists of a transporter, dollies, andauxiliary equipment. The transporter, shown in Figure 13, consists ofthe frame and drive assembly and the turntable and cask assembly.Wherever possible, the drive and frame assemblies are constucted usingcommercially available components that have been proven reliable inindustrial applications. The function of the transporter is to carrythe waste package from the surface facility to the undergroundrepository and then to emplace it. The transporter performs the samefunction in reverse for the retrieval orocess.

As shown in Figure 16, the waste package is placed on a dolly. Thismethod was selected because it simclifies the emplacement andretrieval process, minimizes any loading on the waste package duringthe emplacement and retrieval operations, and allows waste packages ofvarious different shapes and sizes to be handled without al:ering theemplacement system.

Auxiliary equipment is required for performing various minor functions(e.g., to emplace the shielding closure). A complete description ofthe required auxiliary equipment is included in White, in preparation.

At the start of the emplacement operation at the waste-handlingsurface facility, the waste package and dolly are inserted into -hetransporter's shielded cask assembly and transferred to theappropriate emplacement borehole location. The cask is rotated,aligned, and mated to the shielding closure. A screw-drien double-action extension plate, located within the cask, is used to .nsertthe dolly and waste package into the emplacement borehole.Conceptually, the retrieval process involves performing theemplacement process in reverse. However, this does not imply thaz theactual retrieval process is simply the emplacement process in reverse.As discussed in Section 5, the actual retrieval process involvesadditional considerations.

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' .' .

rI

YOKE

WASTE PACKAGE

U")Lnl

ROLLERS

SIDE LOAD BEARINGS

DOLLY COUPLING

Figure 16. Waste Package and Dolly for Horizontal Emplacement

4.0 EXPECTED CONDITIONS

The condition of the drifts and emplacement boreholes at the time ofretrieval will greatly affect both the ease of retrieval and the timerequired for retrieval. The expected conditions within the drifts andemplacement boreholes will be characterized in terms of the followingparameters:

* Temperature* Radiation* Rock Stability* Air Quality

The conditions presented in this section are derived from preliminaryanalyses and design data and are subject to change as the analyses anddesigns are updated. The analyses are based on the assumption thatventilation will only be provided to the emplacement drift until theemplacement process for that drift is completed. Ventilation will bereestablished for periodic inspection, maintenance, or retrieval,until closure of the repository. The baseline data that were used f'rdetermining the conditions presented in this section, are shown inTable 1 (Mansure, 1985).

As additional information is received from supportive studies and :hsrepository and equipment design process, the expected conditions willbe more accurately defined.

4.1 ROCK TEMPERATURE

The rock surface temperature is an important consideration for thescenario development because it not only influences the ventilationrequirements but also affects rock stability. Because of the natureof the heat generation source and the heat transfer mechanisms, thetemperatures within the boreholes and the drifts will vary as afunction of time. The drift rock temperature is affected by variousdesign parameters including waste package thermal output, areal powerdensity, borehole spacing, borehole design, and standoff distance.The rock temperatures presented in this section are the results ofpreliminary calculations using the repository design presented inSection 3 and the input data presented in Table 1. These calculationsare based on assumptions that exclude ventilation and vapor transporteffects. The NNWSI project design goal is to limit the emplacementdrift wall temperature for horizontal emplacement, or the access driftwall temperature for vertical emplacement, to 500C for the first 50years after emplacement. This goal is referred to as the 50/50 goal.Although 500C is an unacceptable temperature for unprotectedreentry, it is close enough to allowable temperature conditions suchthat reenty is possible after a brief ventilation period or with the

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t� .

2

Table 1. Thermal Analysis Data

ROCK PROPERTIES

IN SITU TEMPERATURE

HEAT CAPACITY

THERMAL CONDUCTIVITY

26 C

2.17 MJ / m 3 -QC

1.8 W / m - ec

THERMAL LOADING CONSTRAINTS

ROCK TEMPERATURE AT 1 m 200"C

WASTE FORM TEMPERATURE LIMIT 3500C

AREAL POWER DENSITY 57 kW / ACRE

WASTE CHARACTERISTICS

WASTE AGE (OUT OF REACTOR) 10 YEARS

INITIAL THERMAL OUTPUT 3.0 kW (AVERAGE)

WASTE BURNUP 27.5 GWd / MTU (BWR)32.7 GWd / MTU (PWR)

use of special personal cooling equipment. As the repository designis refined, the design Parameters, which affect the rock temperature,will be modified so that the 50/50 goal and rock temperatureconstriints will be met.

For the vertical emplacement concept, the anticipated temperatures f--rthe emplacement boreholes, the floor of the emplacement drifts, andthe wall of the access drifts are Presented in Figures 17, 18, and 19,respectively (Mansure, 1985). As shown in Figure 19, the access driftwall temperature at 50 years is less than 500C, consistent with theS0/50 goal. With the short standoff distance of 3 m, the emplacementdrift floor temperature rises very quickly (940C at 5 years).Therefore, extensive ventilation cooling is required before reentryinto the emplacement drifts, within a short period of time after wasteemplacement.

For horizontal emplacement, the anticipated temperature histories, forthe emplacement boreholes and emplacement drifts, are provided in-igures 20 and 21, respectively (Mansure, 1985). As shown in Figure21, the emplacement drift temperature at 50 years is less than 500C,consistent with the 50/50 goal. Because of the large standoffdistance of 35 meters, the emplacement drift temperature rises veryslowly. Consequently, minimal ventilation will be required to cooldown a drift before reentry. This allows for quick, inexpensivereentry into the emplacement drifts.

4.2 RADIAT:ON

Preliminary studies have been performed for identifying areas whereradiation shielding may be necessary during the retrieval operation(Dennis, 1984). The permissible-dose equivalent is 5 rem/year forworker exposure. The NNWSI project design objective is 1 rem/yearincluding background radiation levels, under normal operatingconditions (Dennis, 1984).

Radiation in the repository is due to a combination of naturallyoccurring sources and the waste. Naturally occurring radiationresults principally from airborne radon-222 and radon daughters. Theimpact of radon-222 on air quality will be discussed in Section 4.4.The potential for waste package, borehole, and drift surfacecontamination from radon daughters is under investigation. Furtherstudy i4s required for an accurate evaluation of the potential effectof possible radon contamination on retrieval operations.

The waste package surface radiation levels for spent fuel (PWR) areestimated at 17 krem/hour for gamma, and 3.9 rem/hour for neutronradiation (O'Brien, 1984). Using these surface radiation levels andavailable repository and equipment design information as input,studies are being performed to identify the radiation levels that

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230

220 -

210

U 200U

U 190

It 188I¢ I H0

i~~~~~~L'a Li 178

160

150

140 . .I I .0 1 0 20 30 40 50 6

TIME (YERRS)

0

FIGURE 17. BOREHOLE WALL TEMPERATURE - VERTICAL EMPLACEMENT

140

1206

U 100 .a

Fr-

I w~~L

40

0 20 40 6

TIME (YEARS)

0 au

FIGURE 10. FIGUE 10 LMPL-RCEMENT IiRIFT FLOOR TEMPERATURE - VERTICAL EMPLAtCEMENT

U

%.O

a:I-

(L

W F

65 -

60

55

50

45

40

35

30

250 10 20 40 50 60

TIME (YEARS)

80 90

F IGURE 1 9. ACCESS DRIFT TEMPERATURE - VERTICAL EMPLACEMENT

220

210 /

_% 200 -Ua

Ixa:I z 180

w LiN\) IL

H 170

160

1S0 . a _. .

0 10 20 30 40 50 61

TIME (YEARS)

70 90

FIGURE 20. BOREHOLE WALL TEMPERATURE - HORIZONTAL EMPLACEMENT

LIa

Li

re

It

Cc1w(LI-

65

60

55

50

45

40

35

30

25

IwwI

0 10 20 30 40 50 60 70 8s 90 100

TIME (YEARS)

FIGURE 21. EMPLACEMENT DRIFT TEMPERATURE - HORIZONTAL EMPLACEMENT

would be present within the drifts during retrieval operations. Theradiation output is highest at the time of emplacement. Becauseappropriate shielding will be provided at the time of emplacement andthe same equipment will be used for retrieval, waste-generatedradiation should not represent a problem during retrieval.

4.3 ROCK STABILITY

To ensure that the option for retrievability is maintained, the driftsand emplacement boreholes must remain stable throughout theretrievability period. Preliminary calculations indicate that thehost rock can accommodate (1) the anticipated stresses induced in therock by the increase in temperature, and (2) mechanical stressesresulting from the excavation of the drifts (Johnstone et al., 1984).Calculations also indicate that the emplacement boreholes and thedrifts (Agbabian, 1984) will remain stable. Additional studies are

F.-A being performed in support of the design effort, to ensure that ztebo~th drifts will remain stable throughout the retrievability period.

Studies also indicate that standard mining techniques can be used forVh rt I the constructcn of the repository and that standard drift-supportmethods (e.g., rockbolts, wire mesh and shotcrete) will be sufficient

&.4 for drift maintenance (Dravo, 1984), (Hustrulid, :984). Thesecalculations will be updated as design specifications change and rockproperty data are refined. In addition, monitoring will be perfornedto verify the stability calculations.

/4.4 AII QUALY

Ventilation studies are currently under way to ensure that air qualitywill be maintained within regulatory limits (DO0, 1984b). There areno plans to ventilate the emplacement drifts during the caretakerperiod. Therefore, ventilation must be reestablished beforeinitiation of retrieval operations, to ensure that radiological andnonradiological air-quality standards are met.

The main concern regarding air quality is the potential accumulationof naturally occurring radon-222 in unventilated drifts. It has beenestimated that allowable limits for radon-concentration levels couldbe reached within three weeks after ventilation is discontinued. Thecalculations are based upon conservative values of radon-emissionrates. It is anticipated that the concentration level of radon-222can be reduced to acceptable levels by preretrieval ventilation.Consequently, the ventilation system must be designed to provide theair flow necessary for removing contaminants or reducing them toacceptable levels.

I -, 4 4 ,

_ _ __ &s344 j ( A f 2X4AN

4 . 5 sL1.bewy

Using the data for the current emplacement concepts, the followingconditions are expected for standard retrieval:

* The temperature of the drift wall will vary with time.Typical temperature plots are provided in Figures 18, 19,and 21. The design goal is to limit the rock temperatureto 500 C for 50 years in the emplacement drifts for thehorizontal option and in the access drifts for the verticaloption. Because the emplacement drifts will be ventilatedbefore retrieval, the actual temperature of the drift wallwill be lower than indicated.

* The borehole temperature will vary with time as shown inFigures 17 and 20. Retrieval equipment is being developed tooperate within the temperature ranges indicated.

* The design objective for radiation exposure is 1 rem/year(permissible dose equivalent). Studies are under way toensure that this goal is met.

* The drifts will likely be stable, but ini amount ofmaintenance may be required.

* Studies are in progress to define the exp ed air quality,including the potential for radon-222 co amination. MSH.A,NRC, EPA, and DOE standards will be met.

/4AA

l 35 -

9.. .

5 .0 RETRIRVAL SCENARO DEVELCP2MNT

Retrieval scenario development involves defining the conditi.ons thatwill exist during the retrieval process and determining theappropriate steps required to perform the retrieval process.Retrieval scenarios are necessary for assessing compliance with theretrievability performance criteria and for planning retrievaldemonstrations. The development of retrieval scenarios begins duringthe design phase and progresses as the design evolves. As shown inFigure 22, the input for scenario development comes from the designprocess in the form of repository and equipment designs and fromsupportive studies in the form of analyses and tast results. With

this input, the scenario development process generates design crimeriafor use in the design process and data and information for use indefining additional supportive studies. Due to this close interactionbetween scenario development, repository and equipment design, andsupportive studies, scenario development begins during the earlydesign stages and progresses simultaneously with the design processand supportive study efforts. The advantage from the simultaneity cfthis technique is that the required studies and analyses, which needto be performed, are identified at the earliest possible time.

The development of retrieval scenarios must be flexible enough toaccommodate changes in the input information from the design processand supportive studies, yet sufficiently structured to ensure that thedevelopment is reliable, realistic, and comprehensive. Thedevelopment must first consider the regulatory requirements, therepository and equipment designs, and the expected conditionsin the repository during the retrievability period. Then, twoapproaches to retrieval scenario development must be considered--standard retrieval and retrieval under adverse conditions.

5.1 STANDARD RETRIEVAL

Using the design concepts presented in Section 3.0, the expectedconditions presented in Section 4.0, and logical assumptions that canbe derived from preliminary analyses, it is possible to outline astandard retrieval scenario.

By definition, for standard retrieval it is assumed that no adverseconditions exist that could significantly affect the ability to removethe waste safely using standard retrieval procedures. 'However, minormaintenance and cleanup may be required.

A flowchart illustrating the standard retrieval steps is included inFigure 23. The first six steps are designated as the preretrievalassessment steps, whereas the last two steps are the waste-packageremoval steps. These steps could be performed on a drift or panelbasis.

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.

i

ULSIGN CRITERIA

-~~~~~~~~~ ~~~DATA/INFORMATION NEEDS

Figure 22. Interaction Between Design Process, ScenarioDevelopment, and Supportive Studies

DOCUMENTATION REVIEW(DRIFTS)

F -RI-FT AS'SESSMENT

0- ' _

L MINOR MAINT. & REPAIR(AS REOUIRED) -1

L -I

_ RETRIEVAL EQUIPMENTINSPECTION I

L �1_

I.DOCUMENTATION REVIEW(EMPLACEMENT BOR!LES)1. U

EMPLACEMENT BOREHOLEAND WASTE PACKAGE

ASSESSMENT

I I

L MINOR MAINT. & REPAIR(AS REUD) -I

I- (AS REQUIRED)

11 1

DEVELOP REMOVAL PLAN

IWASTE PACKAGE

REMOVALr 7

Figure 23. Standard Retrieval Steps

vI.. . - 38 -

5.1.1 Pre-Retrieval Assessment

Pre-retrieval assessment will ensure that safe, reliable access to th-ewaste package exists; it includes identifying the actual condi tin -athe drifts-and the emplacement boreholes, and performing any minormaintenance, repairs, or ventilation required to bring the driftconditions within operating limits. Pre-retrieval assessment includesthe first six steps shown in Figure 23. A description of those stepsfollows:

1. Documentation Review of Drifts -- Documentation obtainedduring drift mining, repository operation, and subsequentmonitoring will be reviewed.

2. Drift Assessment -- If drift ventilation had beendiscontinued, it would be reestablished. The condition of thedrifts (ramp, access drifts, and emplacement drifts) must beassessed in order to ensure that the drifts are safe andfunctional. Several assessment techniques that will be usedinclude temperature and radiation monitoring, gas sampling,and visual inspection.

3. Minor Maintenance and Repairs for Drifts -- Minor correctiveactions may be required. Examples of these actions includeremoval of minor debris from the drift floor, replacement ofrockbolts, or other minor repairs. These are not actions tocorrect the effects of an adverse condition.

4. Documentation Review of Boreholes and Waste Packages -- Dataobtained during borehole drilling, liner emplacement, wasteemplacement, and operational monitoring, as well as data onthe waste packages within the boreholes, will be reviewed.

5. Borehole Assessment -- To determine the condition at anindividual borehole, an assessment including radiationmonitoring and inspection of the borehole collar, linerequipment flange, and shield plug, will be performed.

6. Minor Maintenance and Repairs for Boreholes -- Minorcorrective actions will be performed on those componentsrequiring repair or adjustment (e.g., collar, shield door,mating collar).

5.1.2 Waste-Package Removal

The last two steps in Figure 23 involve developing the removal planand actually removing the waste. It is assumed that no backfilling isrequired before decommissioning.

7. Removal Plan -- The data from the preretrieval assessmentprocess combined with other relevant input data (e.g., surfacefacility receipt capabilities, etc.) are used to develop awaste removal plan. This plan identifies the sequence of, and

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time schedule for, the removal of waste packages.

8. Waste Package Removal -- The waste package removal processis operationally the reverse of the emplacement process;however-, because the borehole environment will have changed,additional precautions may be necessary.

5.2 RETRIEVAL UNDER ADVERSE CONDITIONS

Retrieval under adverse conditions is required when conditions existthat could significantly affect the ability to safely remove theemplaced waste using standard procedures. The existence of in adversecondition does not necessarily mean that retrieval is impossible orparticularly hazardous; it implies that a nonstandard procedure maybe required for retrieval.

Adverse conditions are caused by the occurrence of specific eventsor processes. Consequently, the process for developing the scenariosfor adverse conditions involves identification and evaluation ofpotential events that could cause an adverse condition.

5.2.1 Identification of Adverse Conditions

Potential events or processes that could result in adverse c-onditionswill be identified through literature reviews, working sessions withstaff professicnals, and peer and management reviews. As informationfrom in situ tests becomes available, it too will be incorporated intothe identification process. To simplify the identification process,the identification method will be applied at each of the three testpoints discussed in Section 5.2.3, and the following grouping ofevents and processes will be used:

1. Natural - This group includes all naturally occurringevents or processes that could cause adverse conditions(e.g., earthquakes, floods, etc.).

2. Repositorv Induced - This group is made up of events orprocesses that might occur because of the existence of therepository. The adverse conditions could result frommining activities, emplaced waste effects, or repositoryoperations (e.g., drift collapse, excessive temperatures,transporter accident, etc.).

3. Human Induced - This group is limited to adverse conditionsthat might result from actions performed by people notassociated with the repository (e.g., sabotage, aircraftaccidents, etc.).

5.2.2 Evaluation of Adverse Conditions

After various potential adverse events and processes have been

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identified, the resulting adverse conditions will be evaluated. T_ensure that the evaluation technique is credible, the evaiuat cr.method will assess the probability and the potential impact ofthe condition, as well as the possibility of design enhancements andprocedural controls to negate or minimize --he impact of the events --processes.

5.2.3 Addditional Retrieval Steps

A credible scenario must consider the possibility of an adversecondition even though the probability is extremely low. Sufficientdata are, as yet, unavailable for developing the treatment andresolution of adverse conditions. However, it is possible toincorporate the steps for consideration of adverse conditions, intostandard retrieval steps, by modifying Figure 23. The modification,presented in Figure 24, involves the addition of three tests for theidentification of adverse conditions, as follows:

* Test 1 - After the drift assessment is completed, theresults are evaluated to determine if an adversecondition exists. If an adverse condition is present,then condition-specific corrective actions and wasteremoval operations are defined and implemented.Otherwise, the standard retrieval process cont4nues.

* Test 2 - After the borehole assessment is completed,the results are evaluated to determine if an adversecondition exists. If it does, then a second test isconducted to determine whether or not the waste packageshould be removed. Providing the radionuclide release-rate performance objectives are not exceeded and removalis impractical, the waste would be left in the borehole.Otherwise, condition-specific corrective actions andremoval operations are defined and the retrieval processis continued. If there was not an adverse condition, thestandard retrieval process would continue.

* Test 3 - During the waste package removal process, it ispossible for an adverse condition to occur. If such anevent occurs during the removal process, a decision ismade to either leave the waste in the borehole or mcdifythe removal plan to allow for the completion of theremoval operation. Otherwise, the removal operationwould continue as defined in the removal plan.

- 41 -

An.

-

Figure 24. Retrieval Steps

- 42 -

6.0 STRATEGY FOR CCHPLIANCE DEMONSTRATION

The ability to retrieve emplaced waste is a performance objective forthe repository as established by the NRC. As such, the ability toretrieve must be demonstrated before submitt4ng the licenseapplication, and the repository must be constructed and operated wit:.the ability to initiate waste retrieval operations. Numerousactivities must be performed in order to demonstrate compliance withthe retrievability requirement and to verify that the ability toretrieve is maintained throughout the retrievability period. ingeneral, the activities fall into the following categories:

* Facility Design Criteria* Equipment Development* Demonstrations* Operational Activities* Scenario Development* Supportive Studies* Quality Assurance

6.1 FACILITY DESIGN CRITERIA

The facilities design criteria must include the ability to retrievethe emplaced waste throughout the retrievability period. Theinfluence of the retrievability requirement on the facilities design,affects three areas--the surface facilities, the underground openings,and the underground ventilation system.

6.1.1 Surface Facility Design

The waste handling facilities must be designed for receiving retrievedwaste. However, the facilities will be constructed to handle onlywaste that is retrieved during retrievability demonstrations or aspart of the performance confirmation program. Surface facilities forhandling retrieval of all of the emplaced waste will not be provided;however, should retrieval of all of the waste be deemed necessary,additional facilities and modifications to existing facilities wouldbe required.

6.1.2 Underground Openings

All underground openings gust remain stable for a longer period oftime than would be necessary without the mandate for retrievability.The openings will be designed to remain stable during theconstruction, retrievability, and decommissioning periods, for a totalof about 100 years.

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a.~...

6.1.3 Ventilation System Design

The retrievability requirement will cause an impact on the design ofthe ventilation system and equipment, includ'ng criteria forventilation control, air filtration, monitoring, and brattice/bulkheadneeds. In addition, local boost fans, 41EPA filtration systems, andcooling systems may be required for controlling temperature and airquality before reentry for maintenance and/or retrieval operations.

6.2 EQUIPMENT DEVELOPMENT

Equipment development begins with the conceptual design phase thatinvolves investigating alternative design concepts and selecting oneof the concepts for feasibility studies. During the feasibilityphase, studies are performed to establish the feasibility ofdesigning, constructing, and operating the required equipment. Afterfeasibility has been established, a detailed design of criticalcomponents is performed. Critical segments of the equipment areconstructed from the detailed designs for use in proof-of-conceptd monstrons. During proof-of-concept demonstrations, designconcept-ma operations which have not been developed previously inindustry are demonstrated. Once the proof-of-concept demonstrationsIl are completed, a full scale, operational prototype is constructed torf"nal testing and demonstration purposes.

If f 4

Rellable equipment capable of drilling emplacement boreholes andemplacing and retrieving the waste packages is necessary. The abilityto perform these functions for vertical emplacement of waste packageswas demonstrated at the Climax facility (NTS) from April 1980 to Marc-:1983 (Patrick, 1985). Therefore, no proof-of-concept demonstrationshould be necessary for vertical emplacement. To provide a basis ofcomparison for the two emplacement options, equipment development forthe vertical configuration will progress to the feasibility designphase and remain there until the-completion of the proof-of-conceptdemonstrations for the horizontal configuration.

SThe design process for horizontal emplacement of waste packages willcontinue through the detailed design phase to allow for constructionof demonstration equipment. Following the completion of the-proof-of-concept demonstrations for the horizontal configuration,a preferred method of emplacement--either vertical or horizontal--will be selected.

6.2.1 Equipment Development - Vertical Option

For the vertical emplacement configuration, the conceptual design ofthe drilling, emplacement, and retrieval equipment has been completed(Stinebaugh, in preparation). The design process will continue onlyif, after the proof-of-concept demonstrations for the horizontalconcept are completed, the vertical option is selected.

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6.2.2 Equipment Development - Horizontal option

The equipment development programs for horizontal emplacement ofradioacti-ve- waste will be discussed by category in the followingorder:

* Emplacement Borehole Drilling and Liner EmplacementEmplacement and Retrieval System

* Retrieval Backup System

6.2.2.1 Emplacement Borehole Drilling and Liner Emplacement

The capability for accurately drilling long horizontal emplacementboreholes and installing liners is being developed. Feasibilitystudies and conceptual designs for drilling and lining horizontalboreholes have been completed (Robbins, 1984a, l984b, 1985). Thedesign process is currently in the detailed design phase. This willbe followed by construction of demonstration equipment to be used inthe proof-of-concept demonstrations, as discussed in Sections 6.3.1.1and 6.3.1.2.

6.2.2.2 Emplacement and Retrieval Equipment

Conceptual design of the emplacement and retrieval equipment is nearcompletion (White, in preparation). Detailed design activities are irprogress for the borehole components and transporter subassemblies,which require proof-of-concept demonstrations (see Sections 6.3.1.2and 6.3.1.3). This will be followed by detailed design of the entireemplacement and retrieval system.

6.2.2.3 Retrieval Backup Equipment

it.V-144 4,11��I 4/_

'nv&'�/ 17

. .

Because of the large number of emplacement boreholes required, it isanticipated that a failure could occur in which a waste package anddolly are left deep within the emplacement borehole, out of reach ofthe transporter retrieval system. A backup retrieval system forrecovering a waste package under such circumstances is currently inthe conceptual design phase. The system is based on a proven conceptthat involves inserting a grapple, which is attached to the end of aheavy drill pipe, into the borehole. The grapple would couple withthe dolly or the waste package for removal. A special shieldingcollar will be developed 'or the protection of the workers during thisoperation.

6.3 -DEMONSTRATIONS

Various demonstrations will be performed to provide assurance that theequipment will be able to remove the emplaced waste. During thedesign phase, necessary proof-of-concept demonstrations will begin at

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the component level and proceed to the system level. Prototypesystems will be demonstrated in simulated in situ conditions. Duringrepository operations and continuing through the decommissioningphase, in situ demonstrations will be performed.

6.3.1 Proof-of-Concept Demonstrations

The drilling, emplacement, and retrieval processes for verticalemplacement in granite have been demonstrated at the Climax facility,NTS (Patrick, 1985). The demonstration indicated that verticaldrilling and emplacement can be performed; consequently, proof-of-concept demonstrations will not be performed. Because the capabilityfor performing these processes has not been demonstrated forhorizontal emplacement, various proof-of-concept demonstrations willbe necessary. The proposed proof-of-concept demonstrations will bediscussed in the following order:

* Borehole Drilling* Borehole Components* Turntable and Emplacement Mechanism* Retrieval Backup System

6.3.1.: Borehole Drilling

Current designs for horizontal emplacement boreholes specifydimensions of approximately 0.85 a in diameter and up to 200 m inlength. A proof-of-concept demonstration will be peformed to verifythe feasibility of drilling long, straight, horizontal boreholes. thetest will utilize a system comprising only the essential componentsfor a feasibility demonstration, to minimize the cost. Following theproof-of-concept demonstration, a complete prototype system will bebuilt and tested.

6.3.1.2 Borehole Components

As required, the feasibility of the design of the borehole components,with the exception of the liner, will be verified during the turntableand emplacement mechanism demonstration, as discussed in Section6.3.1.3. Liner emplacement demonstrations will be performed duringthe borehole drilling demonstration discussed in Section 6.3.1.1. CThe

'4effect of applied loads on the liner will be demonstrated separatelybecause of the critical role for the liner in providing accessibilityfor waste-package removal. The specific processes to be addressed are(1) liner emplacement and (2) liner loadings. The ability to emplacea liner in a long, horizontal borehole will be demonstrated during theprototype drilling system demonstration. 'The liner-loadingdemonstration is required for verifying predicted liner-failure modesand thresholds.

- 46 -.Ar ..

6.3.1.3 Turntable and Emplacement Mechanism

A proof-of-concept demonstration will be performed on the transporterturntable- ad the emplacement/retrieval mechanism. This test willutilize a mock-up of the waste packages and borehole for demonstratir.emplacement and retrieval capability.

6.3.1.4 Retrieval Backup System

critical components of the backup retriever system will bedemonstrated to verify the ability to remove waste packages undernormal and anticipated adverse conditions.

6.3.2 Prototype Demonstrations

Prototype demonstrations will be performed for the emplacementconfiguration that is selected: horizontal or vertical. The equipmentfor use in these demonstrations will be full-scale and fullyoperational. All equipment and operations that will be used forborehole construction and preparation, as well as waste emplacementand retrieval equipment and operations, will be demonstratedincluding:

* Borehole Drilling* Borehole Preparation* Waste Emplacement* Waste Retrieval

6.3.3 In Situ Demonstrations

It is proposed that a training area be established for emplacement andretrieval operations. It is also recommended that representativeboreholes within the repository be set aside in which retrievaloperations would be performed for waste package performanceconfirmation purposes. These boreholes would be fully instrumented.For two reasons, random retrievals from uninstrumented boreholesshould not be performed. First, complete historical data on theborehole environment would not be available, and second, randomrerieval would interfere with efficiency in scheduling and emplacementoperations. In comparison, a fully instrumented test area wouldprovide the data needed to provide historical information for use inthe performance confirmation program and to verify the continuedability to retrieve emplaced waste, while minimizing the impact to theemplacement operations in progress (see Section 6.4.3.1).

6.4 OPERATIONAL ACTIVITIES

Operational activities will be performed during the retrievabilityperiod to ensure that the ability to retrieve emplaced waste is

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maintained. These activities include documentation, driftmaintenance, and the retrieval verification program. As retrievalscenarios develop, any additional operational activities tha: areidentifed will be analyzed and, if appropriate, incorporated into t..eoperations plan. -

6.4*1 Documentation

Comprehensive, concise, and accurate documentation is necessary forproviding a sound foundation for planning potential retrievaloperations. The documentation will include data obtained during thefollowing operations:

* Drift Mining -- Geotechnical conditions encountered duringdrift mining will be documented.

* operational Data -- Any repository operational data that couldcause an impact on the retrieval process will be documented.

* Emplacement Borehole Drilling -- Geotechnical conditionsencountered in the emplacement boreholes will be documented.

* Liner Emplacement -- Any difficulties encountered during lineremplacement that might affect the retrieval process will bedocumented.

* Waste-Package Emplacement -- Waste package data, includinglocation, waste type, waste package ident'fication, and anythermal or radiological data will be documented at the timeof emplacement.

6.4.2 Drift Maintenance

Maintaining the ability to retrieve throughout the retrievabilityperiod places additional emphasis on the underground maintenanceprogram. A routine inspection and maintenance schedule will beestablished for each of the drifts. Any significant deterioraticndetected in the underground openings will be corrected promptly.Appropriate records of maintenance will be kept as part of theperformance verification and quality assurance programs, mentioned,respectively, in Sections 6.4.3 and 6.6. These records will allow forthe early detection of potential problems.

6.4.3 Retrieval Verification Program

The retrieval verification program is being developed to ensure thatthe ability to retrieve the emplaced waste is maintained. Theactivities associated with th's program can be divided into thefollowing categories:

* Monitoring and Data Collection

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* Sample collection and Examination* Waste Package Examination

Careful analysis of the data collected during these activities willprovide a basis for confirming predicted conditions and responses andfor refinifig-the repository design. The retrieval verificationprogram is not a part of the performance confirmation program requiredby the NRC. However, some of the information which is required forthe retrieval verification program may be obtained from theperformance confirmation program to avoid duplication of effort.

6.4.3.1 Monitoring and Data Collection

To verify the performance of the repository and the subsurfaceconditions during the operational phase, a monitoring program will bedeveloped. Potential monitoring activities include measurements ofrock temperature and movement, air quality and temperature, boreholeconditions, and waste package conditions. It is impractical to fullyinstrument each emplacement borehole. Therefore, only a fewspecifically selected boreholes will be fully instrumented. A trainingarea will be provided for testing the retrieval equipment andprocedures and for crew training. This area could also be used forin situ retrievability demonstrations (see Section 6.3.2).

6.4.3.2 Sample Collection

As drift mining and emplacement borehole drilling progresses,occasional rock samples will be collected and analyzed. The analysiswill focus primarily on conf'rmation of thermo-mechanical properties;however, the samples may also be examined for other characteristicssuch as mineralogy and moisture content. The results of theseanalyses will establish a basis for modifying thermal loading, destgn,or construction operations. This will allow compatibility with insitu conditions and the characteristics of incoming waste.

6.4.3.3 Waste Package Examination

Examination of waste packages may be required. It is recommended thatthe waste packages to be examined should be selected from the fullyinstrumented performance confimation area, because a completehistorical data base on the borehole conditions will be available.Random selection of waste packages without this borehole data willyield very little scientific data (see Section 6.3.2).

6.5 RETRIEVAL SCENARIOS

After sufficient-design information is available, scenarios forretrieval under standard and adverse conditions will be developed andrefined. A description of the scenario development process ispresented in Section 5.

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6.6 SUFPCRTIVE STUDIES

During the repository design phase, studies will be performed insupport of retrieval scenario development and compliancedemonstration. The results will be published in topical reports.

C.

6.6.1 Waste Characterization

Waste characterization is required for establishing the thermal andradiological output of the waste packages for the waste types underconsideration. This data will be used as input to many of theproposed studies. The preliminary data currently being used arecontained in O'Brien, 1984. As additional data on the waste to bereceived become available, the waste characterization data will beupdated.

t 6.6.2 Thermal Analyses

Preliminary thermal studies have been performed that provide estimatesof the temperature gradients for the emplacement drifts and boreholes.As the conceptual design process progresses, updating of theseanalyses will be required to incorporate modeling, borehole and driftconfiguration, and input reference data changes.

6.6.3 Rock Mechanics

[~ Preliminary studies indicate that the drifts and boreholes will bestable as required for maintaining the retrieval option. Thesestudies rely on input data described in Sections 6.6.1 and 6.6.2. Asinput data and thermo-mechanical models are refined, rock-stabilityanalyses will be updated.

6.6.4 Borehole-Liner Analysis

Emplacement borehole liners are included in design for the horizontalemplacement option. Depending upon the design that is accepted,liners may or may not be included in the vertical configuration. Theprimary function of borehole liners is to ensure predictable access tothe emplaced waste packages. Various studies are required, to ensurethat the liner will perform this function properly.

i° t 6.6.4.1 Failure Analysis

To ensure that the liner will withstand the environment within theborehole, a failure analysis must be performed. The analysis involvesdefining the loading and environmental conditions that could affectthe performance of the liner and evaluating their potential effectwith respect to the liner's failure modes and thresholds. This

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process actually involves three interrelated analyses--corrosion,welding effects, and liner-stress analyses--which will provide linerdesign criteria.

A corrosidn-analysis is required for determining the potential effectof corrosion on the liner. Two types of tests will be performed. Thefirst set will evaluate the susceptibility of the candidate linermaterials to various corrosion mechanisms. The second set will belong-term corros6on rate tests. These tests must be performed inenvironments that are representative of the anticipated bcreholeconditions, including radiation effects.

A welding analysis will be performed to investigate the effect ofcorrosion and applied loads on borehole-liner welds. The corrosiontests on welded specimens will be performed at the same time as thosefor the candidate materials. A preferred method of welding for thevarious candidate materials can then be selected.

The liner stress analysis will consider potential loading conditions(e.g., thermal expansion, rock fall, canister loading, etc.) andidentify potential failure modes and thresholds resulting from theanticipated leading conditions.

6.6.4.2 Potential Liner Enhancement

Various enhancements to improve the corrosion resistance and str-ctua!performance of the liner have been suggested. They include(1) grouting the liner and (2) corrosion-inhibiting techniques

A preliminary study indicates that grouting the liner is possible.Grouting improves resistance to corrosion and increases structuralsupport. However, there are potentially undesirable aspectsassociated with grouting which require further study for assessing therelative merits of this option.

Various corrosion-inhibiting techniques have been suggested. Theseinclude, among others, the selection of a corrosion-resistant materialfor the liner and sealing of the liner. Each of the suggestedconcepts will be investigated.

6.6.5 Radon Contamination

The contamination investigations related to radon-222 and radondaughters will focus on airborne and surface contamination. For adiscussion of airborne contamination and possible surfacecontamination see Sections 4.2 and 4.4, respectively. Both types ofpotential contamination will be investigated in future studies.

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6.6.6 monitoring System

in support of the performance verification program, studies toidentify essential-monitoring activities will be performed. The focusof these studies will be the development of an accurate and reliablemonitoring system, includ'ng computer ±nstrumentation and senscroptions.

6.7 QUALITY ASSURANCE PROGRAM

To ensure that the activities associated with retreival are perfcrmedproperly and that the appropriate documentation of that performance isretained, a clearly defined quality assurance (QA) program is beingdeveloped. The QA program includes the provisions of the NNWSI QAplan (DOE, 1984c), the requirements and supplements of ANSI/ASME NQA-:(ASME, 1983), and the Code of Federal Regulations, Title 10, Part 50,Appendix B (CFR, 1975).

The requirements set forth by the QA program establish procedures 'orensuring quality of, and documentation requirements for, design,testing, construction, and operational activites. For example, thefacility design criteria, equipment development, and test plans foroperational activities and demonstrations are developed according tospecific QA procedures. And all published data, design ±nformation,and reports are subject to technical peer review and management linereview.

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i

7.0 SU*.*1ARY

Gus -NWSI project -strategy for demonstrating compliance with -heretrievability requirement involves defining basic assumptions,identifying regulatory requirements, and establishing a method of

- demonstration.

7.1 -BASIC ASSUMPTIONS

The basic assumptions used for the development of the strategy fordemonstrating compliance with the retrievability requirement are asfollows:

* The design of the repository at Yucca Mountain willincorporate the option to retrieve the emplaced waste asa planned contingency operation.

* The inclusion of the retrieval option in the repository designwill not compromise the safety of the repository.

* The repository design will include the capability for partialretrieval of the emplaced waste for economic, scientific, orperformance confirmation purposes. This will not degrade theeffectiveness of the repository for containment and isolationof waste, nor will it preclude the continued emplacement ofwaste.

* The probability that total retrieval will be required, becauseof failure of the site to meet established performanceobjectives objectives for the protection of the public and theenvironment, is extremely small.

7.2 REGULATORY REQUIREMENTS

The principal elements of the regulatory requirements that addressretrievability are is follows:

* The repository will be designed so that any or all of theemplaced waste can be removed until the end of theretrievability period. However, should retrieval be required,it might be advantageous to leave some of the emplaced waste,provided the radionuclide containment and isolation performanceobjectives are not exceeded.

* For design purposes, retrieval will be required if therepository fails to meet the established performance objectivesfor the protection of the public ar.d the environment. Thisdoes not preclude the removal of spent fuel for economicreasons as long as the ability of the repository to contain Whe

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%4 . .

waste is not compromised.

* For design purposes, both a retrieval option period of 5oyears and a retrieval period of 34 years have been proposed.This constitutes a maximum retrievability period of 84 yearsfrom first waste emplacement, during which the ability toretrieve emplaced waste must be maintained.

7.3 COMPLIANCE DEMONSTRATION

Compliance with the retrieval option requirement will be demonstratedby performing the following activities:

* Develop facility designs which allow for retr'eval of emplacedwaste.

* Develop equipment designs that ensure waste-retrievalcapability.

* Demonstrate the ability of the equipment to perform waste-retrieval operations.

* Develop operational activities in support of compliancedemonstration.

* Develop scenarios for retrieval under standard and adverseconditions.

* Conduct ongoing supportive studies.

* Develop and conduct a Quality Assurance program.

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REFERENCES

Agbabian Associates, "Comparison Study of the Underground Excavatlonsfor a Nuclear Waste Repository in Tuff," SAND83-7451, Sandia NatcrnalLaboratories, Albuquerque, NXM (in preparation).

ASME (American Society of Mechanical Engineers), "Quality AssuranceProgram Requirements for Nuclear Facilities," ANSI/ASME NQA-1-1983,July 1983.

CFR (Code of Federal Regulations), Title .0, Energy, Part 50,Appendix 8, "Domestic Licensing of Production and UtilizationFacilities," January 1975.

CFR (Code of Federal Regulations), Title 10, Energy, Part 60,"Disposal of High-Level Radioactive Wastes in Geologic Repositories,"January 1984.

CFR (Code of Federal Regulations), Title 40, Protection ofEnvironment, Part 191, "Environmental Standards and Federal RadiationProtection Guidance for Management and Disposal of Spent Nuclear Fue',High-Level and Transuranic Wastes," September 1985.

Dennis, A. W. et al., "NNWSI Repository Worker Radiation Exposure,Volume 1, Spent Fuel and High-Level Waste Operations in a GeologicRepository in Tuff," SAND83-7436/1, Sandia National Laboratories,Albuquerque, NM, 1984.

DOE (Department of Energy), "Generic Requirements for a Mined GeologicDisposal System," OGR/B-2, Office of Civilian Waste Management, 1985a.

DOE (Department of Energy), "Draft Environmental Assessment, YuccaMountain Site, Nevada Research and Development Area, Nevada,"DOE/RW-0012, Office of Civilian Waste Management, 1984b.

DOE (Department of Energy), "Nevada Nuclear Waste StorageInvestigations Quality Assurance Plan," NVO-196-17 (Rev. 3), NevadaOperations Office, 1984c.

DOE (Department of Energy), "Quality Assurance," AlbuquerqueOperations Office, Order AL 5700.6A, May 10, 1982.

Dravo Engineers,Inc., "Effect of Variations in the Geologic Data Baseon Mining at Yucca Mountain for NNWSI," SAND84-7125, Sandia NationalLaboratories, Albuquerque, NM, 1984.

Hustrulid, W., "Preliminary Stability Analysis for the ExploratoryShaft," SAND83-7069, Sandia National Laboratories, Albuquerque, NM,1984.

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U-

Johnstone, J. K. and R. R. Peters, "Unit Evaluation at Yucca MountainNevada Test Site Surmarl Report and Recommendatcons," SAND83-0372,Sandia National Laboratories, A.buquerque, NKM, pp. 6-'5, l984.

Mansure, A., "Expected Temperatures for Spent Fuel Borehole Walls ar.dDrifts," Keystone Memo 6310-85-B, Sandia Nat4onal Laboratories,Albuquerque, NM (in preparation).

NWPA (Nuclear Waste Policy Act of 1982), PL 97-425.

O'Brien, P. D., "Preliminary Reference Waste Descriptions for aRepository at Yucca Mountain, Nevada," SAND84-1848,Sandia National Laboratories, Albuquerque, N.M., 1984.

Patrick, W. C., "Operational and Technical Results from the Spent FuelTest - Climax," UCRL-92065, Lawrence Livermore National Laboratory,Livermore, CA, 1985.

Robbins Company, "Feasibility Studies and Conceptual Design forPlacing Steel Liners in Long Horizontal Boreholes for a prospectiveNuclear Waste Repository in Tuff," SAND84-7209, Sandia NationalLaboratories, Albuquerque, NM, 1985.

Robbins Company, "Small Diameter Horizontal Hole Drilling - State ofTechnology," SAND84-7103, Sandia National Laboratories, Albuquerque,TM, 1984a.

Robbins Company, "Repository Drilled Hole Methods Study - FinalReport," SA;WD83-7085, Sandia National Laboratories, Albuquerque, NM,1984b.

Sandia National Laboratories, "Quality Assurance Program Plan -Organization 6000 Energy Programs Vice Presidency," Sandia NationalLaboratzries, Albuquerque, NM, 1984.

Scully, L. W. et al., "A Comparative Study of Radioactive WasteEmplacement Configurations," SAND83-1883C, Sandia NationalLaboratories, Albuquerque, NM, 1984.

Stinebaugh, R., "Disposal of Canistered Radioactive Waste in VerticalBoreholes -- A Description of the System, Equipment, and Proceduresfor Emplacement and Retrieval," SAND84-1010, Sandia NationalLaboratories, Albuquerque, NM (in preparation).

White, I., "Disposal of Canistered Radioactive Waste in HorizontalBoreholes - A Description of the System, Equipment, and Procedures forEmplacement and Retrieval," SAND84-2640, Sandia National Laboratories,Albuquerque, NM (in preparation).

Wilems, R. E., "Preliminary Assessment of a Technical Basis forEstablishing a Retrievability Period," ONWI-101, Office of Nuclear WasteIsolation, Columbus, OH, March 1980.

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. a

APPENDIX

APPLICABLE FEDERAL REGU'LATIONS

The regulations concerning the retrieval of high-level radioactivewaste from geologic repositories are contained in the KWPA legislatedby congress (NWPA, 1982), the EPA regulation 40 CFR 191 (CFR, 1985),and the NRC regulation 10 CFR 60 (CFR, 1964).

The major NWPA reference to retrieval is contained in Section 122(additional minor references are contained in Sections 2 and 121):

"Sec. 122. Notwithstanding any other provision of thissubtitle, any repository constructed on a site approvedunder this subtitle shall be designed and constructed topermit the retrieval of any spent nuclear fuel placed insuch repository, during an appropriate period ofoperation of the facility, for any reason pertaining tothe public health and safety, or the environment, or forthe purpose of permitting the recovery of theeconomically valuable contents of such spent fuel. TheSecretary shall specify the appropriate period ofretrievability with respect to any repository at thetime of design of such repository, and such aspect ofsuch repository shall be subject to approval ordisapproval by the Commission as part of theconstruction authorization process under subsections (b)through (d) of section 114."

The EPA requirement for retrieval considers both high-level andtransuranic wastes in 40 CFR 191.14(f):

"Disposal systems shall be selected so that removalof most of the wastes is not precluded for a reasonableperiod of time after disposal."

The principal NRC reference to retrievability is in section 111(b) of10 CFR 60. (In the interest of brevity, only subsections (1) and (3)are quoted):

"(b) Retrievability of Waste. (1) The geologicrepository operations area shall be designed to preservethe option of waste retrieval throughout the periodduring which wastes are being emplaced and, thereafter,until the completion of a performance confirmationprogram and Cotmission review of the information

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.%..

obtained from such a program. To satisfy thisobjective, the geologic repository operations area shallbe designed so that any or all of the emplaced wastecould be retrieved on a reasonable schedule starting atany time up to 50 years after waste emplacementoperations are initiated, unless a different time periodis approved or specified by the Commission. Thisdifferent time period may be established on acase-by-case basis consistent with the emplacementschedule and the planned performance confirmationprogram...(3) For purposes of this paragraph, areasonable schedule for retrieval is one that wouldpermit retrieval in about the same time as that devotedto construction of the geologic repository operationsarea and the emplacement of wastes."

in addition to other minor references to retrieval in Sections 102(d),133(c), 133(e), and 135(b)(3), 10 CFR 60 also addresses other issuesthat directly affect the design of the retrieval system. These issuesinclude considerations for design criteria, quality assurance,performance confirmation, and potentially adverse conditions andevents.

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DISTRIBUTION LIST

B. C. Rusche (RW-1)DirectorOffice of Civilian Radioactive

Waste ManagementU.S. Department of EnergyForrestal BuildingWashington, DC 20585

Ralph Stein (RW-23)Office of Geologic RepositoriesU.S. Department of Energytorrestal BuildingWashington, DC 20585

J. J. Fiore, (RW-22)Program Management DivisionOffice of Geologic RepositoriesU.S. Department of EnergyForrestal BuildingWashington, DC 20565

M. W. Frei tRW-23)Engineering & Licensing DivisionOffice of Geologic RepositoriesU.S. Department of EnergyForrestal BuildingWashington, DC 20585

E. S. Burton (RW-2S)Siting DivisionOffice of Geologic RepositoriesU.S. Department of EnergyForrestal BuildingWashington, D.C. 20585

C. R. Cooley (RW-24)Geosciences & Technology DivisionOffice of Geologic RepositoriesU.S. Department of EnergyForrestal BuildingWashington, DC 20585

V. J. Cassella (RW-22)Office of Geologic RepositoriesU.S. Department of EnergyTorrestal BuildingWashington, DC 20585

T. P. Longo (RW-25)Program Management DivisionOffice of Geologic RepositoriesU.S. Department of EnergyForrestal BuildingWashington, DC 20585

Cy Klingsberg (RW-24)Geosciences and Technology DivisionOffice of Geologic RepositoriesU. S. Department of fnergyForrestal BuildingWashington. DC 20585

B. C. Gale (RW-25)Siting DivisionOffice of Geologic RepositoriesU.S. Department of EnergyForrestal BuildingWashington, D.C. 20585

R. J. Blaney (RW-22)Program Management DivisionOffice of Geologic RepositoriesU.S. Department of EnergyForrestal BuildingWashington, DC 20585

R. W. Gale (RW-40)Office of Policy, Integration, andOutreach

U.S. Department of EnergyForrestal BuildingWashington, D.C. 20585

J. E. Shaheen (RW-44)Outreach ProgramsOffice of Policy, Integration andOutreach

U.S. Department of EnergyForrestal BuildingWashington, DC 20585

J. 0. Neff, ManagerSalt Repository Project OfficeU.S. Department of Energy50S Xing AvenueColumbus, OH 43201

*.V ...

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D. C. Newton (RW-23)Engineering & Licensing DivisionOffice of Geologic RepositoriesU.S. Departmenteof EnergyForrestal BuildingWashington, DC 20585

0. L. Olson, ManagerBasalt Waste Isolation Project OfficeU.S. Department of EnergyRichland Operations OfficePost Office Box 550Richland, WA 99352

D. L. Vieth, Director (4)Waste Management Project OfficeU.S. Department of EnergyPost Office Box 14100Las Vegas, NV 89114

D. F. Killer, DirectorOffice of Public AffairsU.S. Department of EnergyPost Office Box 14100Las Vegas, NV 89114

P. M. 3odin (12)Office of Public AffairsU.S. Department of EnergyPost Office Box 14100Las VeSas, WV 89114

B. W. Church, DirectorHealth Physics DivisionU.S. Department of EnergyPost Office BOx 14100Las Vegas, WV 89114

Chief, Repository Projects BranchDivision of Waste ManagementU.S. Nuclear Regulatory CommissionWashington, D.C. 20555

Document Control CenterDivision of Waste ManagementU.S. Nuclear Regulatory CormissionWashington, D.C. 20555

S. A. Mann. ManagerCrystalline Rock Project Of f-cQU.S. Department of Energy9800 3outh Cass AvenueArgonne, IL 60439

K. Street, Jr.Lawrence Livermore NationalLaboratory

Post Office Box 808Kail Stop L-209Livermore, CA 94550

L. D. Ramspott (3)Technical Project Offlcer for YFWSILawrence Livermore National

LaboratoryP.O. Box 808hail Stop L-204Livermore, CA 94550

W. J. Purcell (RW-20)Office of Geologic RepositoriesU.S. Department of EnergyForrestal BuildingWashington, DC 20585

D. T. Oakley ('4)Technical Project Officer for MWUSILos Alamos National LaboratoryP.O. Box 1663Mail Stop F-619Los Alamos, NM 87545

W. W. Dudley, Jr. (3)Technical Project Officer for NNWSIU.S. Geological SurveyPost Office Box 25046418 Federal CanterDenver, CO 80225

NTS Section LeaderRepository Project BranchDivision of Waste ManagementU.S. Nuclear Regulatory CommissionWashington, D.C. 20555

V. M. GlanzmanU.S. Geological SurveyPost Office Box 25046913 Federal CenterDenver, CO 80225

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I t

p. . PrestholtNRC Site Representative1050 East Flamingo RoadSuits 314Las VegasIv 89109

M. E. SpaethTechnical Project Officer for NXWSZScience Applications

International CorporationSuite 407101 Convention Center DriveLas Vegas, NV 89109

SAIC-T&MSS Library (2)Science Applications

International CorporationSuite 407101 Convention Center-DriveLas Vegas, NV 89109

W. S. Twenhofel, ConsultantScience Applications

International Corp.820 Estes StreetLakewood, CO 89215

A. E. GurrolaGeneral ManagerEnergy Support DivisionHolmes & Narver, Inc.-Post Office Box 14340Las vegas, NV 89114

J. A. Cross, ManagerLas Vegas BranchFenix & Scisson, Inc.Post Office Box 15408Las Vegas, NV 89114

Neal Duncan (RW-44)Office of Policy, Integration, and

OutreachU.S. Department of EnergyForrestal BuildingWashington, DC 20S8S

J. S. WrightTechnical Project Officer for mWstWestinghouse Electric CorporationWaste Technology Services DivisionNevada OperationsPost Office Box 708Mail Stop 703Mercury, NV 89023

ONWI LibraryBattelle Columbus LaboratoryOffice of Nuclear Waste Isolation505 King AvenueColumbus, OH 43201

W. M. Hewitt, Program ManagerRoy F. Weston, Inc.2301 Research Blvd., 3rd FloorRockville, MD 20850

H. D. CunninghamGeneral ManagerReynolds Electrical &

Engineering Co., Inc.Post Office Box 14400Mail Stop 555Las Vegas, UV 89114

T. Hay, Executive AssistantOffice of the GovernorState of NevadaCapitol ComplexCarson City, NV 89710

R. R. Loux, Jr., Director (3)Nevada Agency for Nuclear ProjectsNuclear Waste Project OfficeState of NevadaCapitol ComplexCarson City, NV 89710

C. H. Johnson, TechnicalProgram ManagerNevada Agency for Nuclear ProjectsNuclear Waste Project OfficeState of NevadaCapitol ComplexCarson City, NV 89710

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John FordhamDesert Research InstituteWater Resources CenterPost Office Box-60220Reno, WV 89506

Department of ComprehensivePlanning

Clark County225 Bridger Avenue. 7th FloorLas Vegas, RV 89155

Lincoln County CoumissionLincoln CountyPost Office Box 90Pioche, UV 89043

Community Planning andDevelopment

City of North Las VegasPost Office Box 4086Worth Las Vegas, MV 89030

City IanagerCity of HendersonHenderson, WV 89015

W. A. NormanProject ManagerBechtel National, Inc.P. 0. Box 3965San Francisco, CA 94119

Flo ButlerLos Alamos Technical Associates1650 Trinity DriveLos Alamos, Now Mexico 87544

Timothy G. BarbourScience Applications

International Corporation1626 Cole Boulevard, Suite 270Golden, CO 80401

E. P. 8innallflield Systems Group LeaderSuilding 50B/4235Lawrence Berkeley LaboratoryBerkeley. CA 94720

Dr. Martin MifflinDesert Research InstituteWater Resources CenterSuite 12505 Chandler AvenueLas Vegas, NV 89120

Planning DepartmentNye CountyPost Office Box 153Tonopah, NV 89049

Economic DevelopmentDepartment

City of Las Vegas400 East Stewart AvenueLas Vegas, NV 89101

Director of CommunityPlanning

City of Boulder CityPost Office Box 367Boulder City, UV 89005

Colmission of theEuropean Coimunities

200 Rue de la Loi8-1049 BrusselsBELGIUM

Technical Information CenterRoy F. Weston, Inc.2301 Research Boulevard,Third Floor

Rockville, MD 20850

R. HarigParsons Brinkerhoff Quade &

Douglas, Inc.1625 Van Ness Ave.San Francisco, CA 94109-3678

Dr. Madan M. Singh, PresidentEngineers International, Inc.98 East Naperville RoadWustmont, IL 60559-1595

Roger HartItasca Consulting Group, Inc.P.O. Box 14806Minneapolis, Minnesota 55414

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Virsil LoweryCffice of Geologic RepositoriesOffice of Civilian RadioactiveWaste Kanagement

U. S. Department of Energy1000 Independonce AvenueRW-23 (FORSTL), &c 75-091Washington, DC 20585

Larry SkousenChief, Technical Development

& Engineering BranchWaSte Kanagement Project OffIceNevada Operations OfficeU. S. Department of £nergy2753 South Highland DriveP.O. Box 1440Las Vegas, NV 89114

Keith RobinetteProgram EngineerU. S. Department of EnergyNWTS Program Office505 King AvenueColumbus, OH 43201

James L. AshRoy F. Weston, Inc.2301 Research Blvd.Third FloorRockville, MD 20850

Bruce NicollRichland Operations Office825 Jadwin AvenueP.O. Box 550Richland, WA 99352

Dick KingsleyRepository Project OfficeOffice of Nuclear Waste

isolationBattelleProject Management Division505 Xing AvenueColumbus, OH 43201

A. E. CottamEngineering Desuin DepartmentBasalt Waste Isolation ProjectRockwell Hanford OperationsP.O. Box 800, CDC 01 Building1100 Jedvin BuildingRichland. WA 99352

63006310631063116311631163116311631163116311631163116311

R. W. LynchT. 0. HunterCentral FileL. W. ScullyC. MoraA. W. DennisT. W. E2lintonR. R. HillT. LaubM. R. KacDougellA. R. MoralesJ. T. NealP. D. O'BrienC. 0. Shirley

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6311 C. V. Subramanian631'.2 r. W. Bingham6312 S. KC. Hayden6312 B. S. Langkopf6312 J. G. Yeager6313 T. E. BlojVaZ6313 E. A. Klavetter6313 F. B. Nimick6313 A. Stevens6314 J. R. Tillerson6314 B. Khgartner6314 J . A. Fernandez6314 R. J. Flores (20)6314 A. J . Kansure6314 R. E. Stinebaugh (10)6314 K. D. Young6315 S. Sinnock6315 D. H. Zeuch (2)6332 WKH Library (20)6430 W. R. Ortiz3141 S. A. Landenberger (5)3151 W. L. Garner (3)8024 P. W. Dean3154-3 C. H. Dalin (28)

for DOCE/OSTILATA B. Brazier (3)LATA M. RobbLATA 1. White

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