ML20246B881

Forwards Advisory Committee & Consultant Rept - 008

ML20246B881
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Issue date:	04/19/1989
From:	Schofer H NRC ADVISORY COMMITTEE ON NUCLEAR WASTE (ACNW)
To:	Hoyle J NRC OFFICE OF THE SECRETARY (SECY)
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NACNUCLE, NUDOCS 8905090206
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Text

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..y.. ,g . UNITED STATES fj "

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. NUCLEAR REGULATORY COMMISSION

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' ADVISORY COMMITTEE ON NUCLEAR WASTE ,

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i April 19, 1989 i

MEMORANDUM FOR: John C. Hoyle, Advisory Committee Management Officer FROM: H'. a1/~S50fer, Chief Technical Information Group, ACNW

SUBJECT:

ACNW COMMITTEE AND CONSULTANT REPORTS The enclosed documents were prepared by or for the Advisory Committee on Nuclear Waste since the last submission on March 16, 1989.

In accordance with the Federal Advisory Committee Act (PL92-463) Sub-section 10(d) and Section 13, nine copies of each document are being forwarded, one copy for your retention and eight copies to the U. S.

Library of Congress.

Attachment:

"ACNW Committee and Consultant Reports - 008" cc: J. Fitzgerald, OGC, w/o attmt 8905090206 890503 PDR ADVCM NACNUCLE PDC

ACNW COMMITTEE AND CONSULTANT REPORTS - 008 Submitted in Accordance with Sections 10 and 13 of the Federal Advisory Committee Act March 1989

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C0NTENTS '

DATE I)

SUMMARY

LETTER 04/11/89 II) ACNW CONSULTANTS REPORTS

1) ACNWC-0005 Carter ltr to Moeller re Study Plan 03/13/89 for Study 8.3.1.2.2.2, " Water Movement Test"

2) ACNWC-0006 Moody memo to Parry re Review of DOE /YM 03/13/89 Study Plan for Study 8.3.1.2.2 " Water Movement Tests"

3) ACNWC-0007 Krauskopf memo to ACNW re Review of 03/20/89 DOE Study Plan on Water Movement Tests i

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7, g-E NUCLEAR REGULATORY COMMISSION ADVISORY COMMITTEE ON NUCLEAR WASTE 0, WASHINGTON, D.C. 20666

..... - April 11, 1989 l

'The Honorable Lando W. Zech, Jr.

Chairman 1 U.S. Nuclear Regulatory Comission i

Washingten, D.C. 20555

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SUBJECT:

EIGHTH MEETING 0F THE ADVISORY COMMITTEE ON NUCLEAR WASTE, MARCH 23, 1989, BETHESDA, MD The Advisory Comittee on Nuclear Waste (ACNW) held its 8th meeting in Bethesda, MD on March 23, 1989. A sumary of actions is presented below.

, REPORTS, LETTERS AND MEMORANDA The Comittee completed a letter to you on ACNW staffing support recomenda-tions on March 24, 1989.

ACTIONS, AGREEMENTS, ASSIGNMENTS AND REQUESTS 1 I

. DOE Presentation on the Site Characterization Study Plans The Comittee was briefed by representatives of the DOE on the relationship i of the study plans to-the Site Characterization Plan, the current status of (

study plan development, and quality assurance controls applied to the study l plans. This session was for information. No action was taken by the Comit- i

, tee. I ESF Study Plan 8.3.1.2.2.2: Water Movement (Tracer) Tests The Comittee was briefed by Drs. J. Moody and K. Krauskopf, ACNW consult-ants, on an Exploratory Shaft Facility-related study plan, Water Movement Tests. A written report on this matter was also submitted by Dr. M. W.

Carter. In addition, the Comittee had the benefit of discussions with representatives of DOE and their contractors on the chlorine-36 tracer tests.

No action was taken by the Comittee.

Status of the Site Characterization Analysis (SCA)

The Comittee was briefed by Mr. Robert Browning, NMSS, on the current status of the SCP review and future schedule for ACNW review of the SCA. Mr. Brown-ing indicated that the NRC staff would be available some time after April 7, 1989, to discuss their coments as presented in the SCA .

The Comittee agreed to schedule 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> during the April meeting to continue these discussions,

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'The Honorable Lando W. Zech, Jr.-

April 11,.1989 Future ACNW Activities 4 The Comittee agreed to schedule two additional full Comittee meetings, May 11, 1989 and June 13, 1989, for reviewing the. Site Characterization Analysis of the DOE SCP. If . time permits, the meetings will also include other topics.

The Comittee agreed to place on its calendar a visit to the Center for

Nuclear Waste Regulatory Analyses (CNWRA) in San Antonio, Texas, in July 1989.

The Comittee reconfirmed its intention of visiting the West Valley Demonstra-tion Project in the fall of 1989.

The Comittee agreed to consider the draf t NRC scoping package for. a proposed rulemaking, " Design Basis Accident (DBA) Dose Limit" for the HLW repository.

The Comittee agreed to consider Regulatory Guide 3.61, " Standard Format and

. Content for a . Topical Safety Analysis Report for a Spent Fuel Dry Storage Cask," when time permits.

FUTURE-ACTIVITIES The Comittee agreed to the tentative future agenda as shown in Appendix A.

Sincerely, k

Dade W. Moeller Chairman I

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) APPENDIX A FUTURE AGENDA 9th ACNW Meeting on April 26-28, 1989 Meeting with the Comission (0 pen) -

The Comittee will meet with the Comission to discuss a variety of topics, such as:

- Review procedures of SCP and SCA SCP Study Plans Meeting with DOE /NRC/ state of Nevada on CDSCP and SCP Review Plan

- West Valley Demonstration Project Division of High-Level Waste Management FY89 Program Greater-Than-Class-C radioactive waste  !

Other items as identified by the Comission Mixed Waste (0 pen) - The Comittee will be briefed by NRC staff and NUMARC on the status of the disposal of mixed wastes.

Post Closure Seals (0 pen) - The Comittee will be briefed on the technical position on post closure seals in an unsaturated media.

Update on the Site Characterization Plan (0 pen) - The Comittee will be briefed on the status of the NRC review of the SCP. The Comittee will discuss whether the data that the state of Nevada has requested can be obtained in a realistic time period.

Expedited Handling of Petitions for Disposal of Radioactive Waste Streams that are Below Regulatory Concern and Update on the BRC Policy Statement (0 pen) -

The Comittee will be briefed on the procedures and schedule proposed by the NRC staff for the expeditious handling of petitions, which includes early ACNW involvement.

Waste Confidence Rulemaking (0 pen) - The Comittee will meet with the NRC staff to discuss the preliminary findings on waste confidence rulemaking.

Licensing Support System (0 pen) - The Comittee will be briefed on the development of the Licensing Support System for the High-Level Waste Repository.

Comittee Activities (0 pen) - The Comittee will discuss anticipated and proposed Comittee activities, future meeting agenda, and organizational  ;

matters, as appropriate. Discussions will also include critical issues '

related to the high-level waste repository.

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APPENDIX A 8TH ACNW MEETING i

10th ACNW Meeting ~on May 11, 1989 (tentative)

Update on the Site Characterization Plan (0 pen) - The Comittee will be briefed on the status of the NRC review of the SCP and will review the Site CharacterizationAnalysis(SCA).

Quality Assurance (0 pen)' -

As time permits, the Comittee will be briefed on the status of NRC/D0E. interactions on the DOE Quality Assurance Program.

Comittee1 Activities - (0 pen) - The Comittee will discuss anticipated and proposed Comittee - activities, future meeting agenda, and organizational matters, as appropriate.

lith ACRW Meeting on June 13, 1989 (tentative)

Site Characterization Analysis' (0 pen) - The Comittee will be briefed on the NRC review of the SCP and will. continue review of the SCA Comittee Activities (0 pen) - The Comittee will discuss anticipated and proposed Comittee activities, future meeting ' agenda, and organizational matters, as appropriate.

12th ACNW Meeting on June 28-30, 1989 (tentative)

Site Characterization Analysis (0 pen) - The Comittee will finalize coments on the SCA, as needed.

l EPA low Level Waste Standards (0 pen) The Comittee will be briefed on the  !

release standards for LLW disposal sites.  !

Waste Management Research Program and Strategy Plan (0 pen) -

The Comittee will be briefed on HLW and LLW research programs.

. Performance Assessment (0 pen) -

The Comittee will be briefed on th NRC approach to performance assessment and status of activities (NMSS/RES Memo- (

randumofUnderstanding).

Greater Than Class C Radioactive Waste (0 pen) - The Comittee will be briefed on the DOE storage and disposal of Greater Than Class C radioactive waste.

13th ACNW Heeting on July 26-27, 1989 (tentative)

Status of Cementatious Waste Forms (0 pen) - The Comittee will be briefed on the status of cementatious waste forms.

i APPENDIX A 8TH ACNW M:ETING 14th ACNW Meeting on August 3-4, 1989 (tentative)

Retrievability Demonstration -(0 pen) -

The Committee will be briefed on the Technical Position on demonstration of retrievability during site characteri- I zation.

Tectonic Models (0 pen) -

The Comittee will be briefed on the technical position on tectonic models, ,

15th ACNW Meeting on September 13-15, 1989 (tentative)

Data Availability (0 pen) -

The Committee will invite representatives of DOE and USGS.to discuss delays in making data available and coming to closure Meeting with Director of Office of Nuclear Reactor Regulation (NRR) (0 pen) -

The Committee will be briefed by NRR on the licensing program for LLW han-dling sys tems , fuel compaction, decontamination and decommissioning. The Committee will discuss any crossover issues with representatives of NMSS and EDO.

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00AlWC- ddc MELVIN W. CARTER, Ph.D.

International Radiation Protection Consultant March 13,1989 ,,

. 1 Dr. Dade W. Moeller, Chairman Y Advisory Committee on Nuclear Waste U.S. Nuclear Regulatory Commission T > l (. @If Washington, D.C. 20555

Dear Dade:

I've received and reviewed the Study Plan for Study 8.3.1.2.2.2," Water Movemeni} Test".

This Study Plan is dated January 19,1989,and was prepared by the Los Alamos Scientific Laboratory as a part of the construction phase Exploratory Shaft Facility study plan.

The primary purpose of the proposed test is to determine the rate of water movement downward through the unsaturated zone beneath Yucca Mountain. It will be most useful if the rate of such water movement is extremely slow.

The use of measurements of chloride concentrations and chlorine isotopic compositions in samples of soil and tuff collected during the mining of the exploratory shaft is the basis of this proposed method. The method is in the developmental process and should show the best promise if water movements are between 105 to 106 years.

I see no adverse effects on the repository from the proposed sampling and analysis program. However, there are several possible circumstances which could make interpretation of results difficult. These circumstances are generally identified and discussed in the Study Plan.

The one item (exception) that is not addressed in sufficient detail is the production of chlorine-36 underground due to neutron capture by chlorine-35. The Study Plan  ;

indicates calculations will be done to determine the effect of such production on data '

interpretation of the major test parameters. There is no mention of an experimental program to collect data to determine the quantities of chlorine-36 produced by in situ neutron capture (chlorine 35).

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1 l 4621 Ellisbury Drive, Atlanta, Georgia 30338 l

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. , 9 Dr. Dade W. Moeller 1 Page 2 j March 13,1989 r

Therefore, it must be assumed that sufficient information and data are available to

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make the indicated calculations. If this is the case, such calculations should have been (be) made and their effects, if any, should have been (be) discussed in the Study Plan as ]a to possible constraints on test data interpretation.

With this one reservation, I believe the proposed test should be used as one method to determine water movement downward through the unsaturated zone beneath Yucca  !

Mountain. J It is hoped this information will be ofinterest and use to you.

Sincerely yours, Melvin W. Carter i I

MWC/bc i l

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J.E3. Moocly & Accociatco

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'1989 West Fifth Avenue, Suite 11 88////)C-gg d Columbus, Ohio 43212

.,[814)487-1101 I

March 13, 1989 MEMORANDUM FOR: S. J. S. Parry, ACNW Senior Staff Engineer j FROM: J. B. Moody, ACNW Consultant

SUBJECT:

Review of DOE /YM Study Plan for Study l 8.3.1.2.2 - Fater Movement Tests This Site Study Plan has stated that chemical analyses of the isotopic chlorine-36 composition in Yucca Mountain soil and tuff j samples, as a function of depth, can be used to time the rate of i water movement from the surface through the vadose zone, and into l the saturated water zone. Three specific items are critical to >

this test: (1) sample procedure, (2) chemical analytical techniques, and (3) data collection, analysis and interpretation.

The sampling procedure is marginally acceptable as it has been defined. Table la itemizes three sample possibilities for which the Water Movement Tests Site-Study Plan method is listed as I third in the order presented in the table. The problem with the SSP sampling procedure is potential water and explosive contamination of the rubble, and the poor depth measurement given ,

the number of feet explosively removed at a given horizon. The i proposed measurement of traceable bromine (20 ppm Br) input into the Well J-13 water and chlorine content of mining explosives has been proposed as techniques for determination of the amount of contamination per sample. Those tests mean that all chlorine-36 i measurements will have to be corrected for each possible j contamination, and whether that correction is valid for each  !

sample is questionable because of the overall variability in the j useage of both water and explosives at each separate horizon. l The proposed methodology for rubble collection is also a potential for contamination: in addition to placing the rubble in 1 a barrel container with out any protection; when it is taken up j the shaft, or placed on the surface before its permanent storage 4 is completed, contamination is possible. Table 2 lists various materials needed for the sample collection procedure with Table 3 outlining the SSP technical procedures, stating that they have not yet been defined.

The sample preparation for analysis has some drawbacks. The useage of short leach times in order not to remove chlorine within the host-tuff rock will have to be proven to be valid.

l A carefully chosen, specific number of samples analyzed for I

( chlorine-36 should also be analyzed for their total chemical content (major, minor, and trace elements).

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" The analytical procedures to be utilized for all samples need to be described. Chloride concentration is the only procedure that (

has been identified (Table 3). The contractor (s) responsible for '

the data collection and chemical analyses have not been identified in this SSP. Which tandem accelerator to be used for chlorine-36 and mass spectrometer for chlorine-37 analyses have not been specified. Therefore, the necessary proposed analytical work and data collection is very incomplete in this SSP to be used.in tracing water movement.

Interpretation of chlorine-36 data maybe difficult in specific instances (in addition to sample contamination). Anions may move faster than cations because cations may exclude the anions in the water. Chloride movement in water is always nonvolatile i.e.

fluid, which can mean that with different water pulses, chlorine-36 will remain in the fluid water, not in the vapor phases. The measured chlorine-36 can, also, then be a mixing of chloride ions from more than one fluid-water addition, i.e. episodicity in water's input and movement vertically or horizontally.

The chlorine-36 measurements may be utilized in YM hydrologic modeling. However, this analytical information most probably will lead to non-uniform hydrologic flow because fractures are present throughout the tuffaceous rock. Potential lateral rather j than vertical flow may occur in the upper units - Tiva Canyon and Pah Canyon, particularly. Chlorine-36 has, also, not been an atmospheric constant during the Quaternary Period because of high-level surface Pacific nuclear explosions during 1952 and 1962. This " bomb pulse" will have to be evaluated, specifically, if the chlorine-36 values are higher than the measured background amount, which is assumed to have originated from the atmosphere sometime in the past 2 million years.

Integration of this work with the USGS hydrogeochemical work is very important for modeling the YM hydrology. Chlorine-36 should be analyzed in the completely saturated hydrologic zone for the information available on its movement. In fact, this SSP only I postulates obtaining data to the repository horizon, which is l only a comoonent part of the complete hydrologic system. Data should be collected from the repository horizon to the water table itself (an addition to the arguement for a separate dry  ;

hole for chlorine-36).

The QA Support Documentation (Appendix A) and Technical Procedures (Table 3) are very incomplete at this time and inadequate for finalization of the SSP. Have some of the QA documents met their " Anticipated Date of Issue" as of January 19897 In conclusion, this SSP is presently not adequately completed to k meet NRC approval.

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.o Additional References Elmore, D'. and F. H. Phillips, 1987. " Accelerator Mass Spectrometry'for Measurement of Long-Lived Radioisotopes".

Science 2,'lfi, 54 3-550.

Phillips, F. M., J. L. Mattick, and T. A. Doval, 1988.

" Chlorine'36 and Tritium from Nuclear Weapons Fallout as Tracers for Long-Term Liquid and Vapor Movement in Desert Soils". Water Resources Res. 21, 1877-1891.

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• _4 Table la: Proposed Sampling Procedures (Moody, 1989).

A. Ideal Samolina

1. separate from ESF-1, a DRY air drilled rock core, which allows exact sample depth to be measured and f

no water contamination

2. non-contaminated sample collected, placed in a plastic. bag, then emplaced in a sealed sample container with top and bottom depths specified B. Reasonable Samolina

1. ESF-1 shaft blasting

2. DRY, air drill, a horizontal core into the ESF.

wall with the sample depth measured

3. sample collection as specified in (2)'under ideal sampling C. Marainal Samplina

1. ESF-1 shaft blasting

2. rubble collection moved to surface

3. rubble stored a barrel container to be transported

4. alleviated chlorine-36 measurements (i.e.

contamination)

a. bromide (20 ppm) added to J-13 water, to then be analyzed in the rubble for water intrusion

b. chloride content of mining explosives determined for potential addition of cloride to rubble 1

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Eeview of DGE Study }1an on Vater I:ovement Tests DOE proposes to estinate rates of water novenent in the vadose zone at Yucca Mountain fron measurements of the radioactive chlorine isotope, 36C1, in samples of tuff taken at many levels in a projected chaft 450 m deep. This is a promising nethod of determining agen of very old water, but it hac not yet been widely used and so far as I know has never been applied to a situation like that at Yucca Mountain.

Inthink I places it where it han been tried, reported results have of ten been less than clearcut.

is worth trying at Yucca 1:ountain, but only with two provisos: (1) that it not be relied on as tha only way to estiente rates of water novenent, but used in cenbination with other methods, and (2) that the ponribility of ambiguous renults be clearly recognized.

Peacons for percible rcenarios snible a-biguity in the results can be suggested by considerin6 years (1) Thebase at the r.amples could of the chow a regular increase of age downward, say to450 000 shaft. ,

This would be convincing evi6ence that water has been percolating preving that the downward at a uniform rate of 1 mm/yr, and would go far toward site in well qualified for reponitory construction.

the top.

(2) Samples near the botton could show a higher ratio of 36 C1/C1 than those at This would nean that water carrying fallout from the racific bomb tests has moved the cite. m downward in 30-odd years, and would probably be reSarded as disqualifying 450 location, but tnis would hardly be convincin5 to skeptics.It could ctill be (3) The ratio N all the way down. C1/C1 could remain constant within the limits of measurement

!!ccause a decrease would be detectable only if the water was more than 30,000 years old, this result could neun either that .:ater was noving very ra;anywhere or idly dos.;nward, or that the botton water had required 30,000 years for the descent, in between.

The cite would be neither qualified nor disqualified.

(4) Mostwith even possibly }.robably the neasured ages will increase doanward but irregularly, reversals.

Thir could be interpreted in nany ways: water cop 1d have noved downward in tenporally widely rpaced pulses, the path of water movement could have changed over tine, the amount of pristine chlorine contributed to the

- sanples fron the variouc tuff layers could be different, and so on. Slow movement in argunent.

to cer eral would be indicated, but proof of the rite's qualification would be open Thus it seens to me that ccenario (1) would help greatly in qualifying the site, i scenario (2) would probably dislualify it, and the more likely scenarios (3) and (4) would only add fuel to current argunents.  !

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per. M e con;'.cationr. in water novenentnet ch or. Pfe ', re3 roduce \

3 thru tilted and faulted layers of tuff. {

wat er could 1 aces nix .citiwhere old water it or r.cve undercould it, are be re*ained for long periods, ande whe The

.htther porribilit the N ier seen ro nuncrour and so un} redictable that one can y ask fairlevident can rive an interpretable }icture of water .cvenent.C1 The flos nothod, or any n! ,

the propertier of the different tuf f layers; itof courre, are the nort part enent only and co obv:cus neaning. follo. s rinpler downward paths, no that water ages night have mo Jrc]cced neucurements should be tried.It teens to ne th.t thir porribility is grert eno The rtudy llan ir well presented.

technical hnve bach G cound.and an easy familiarity eith the pertinent litItr authors evide 1 erature. They feasible, and the; devised a 3 an cf action that will not he easy to carry outbebut tha seen aware of the nany things that can go wrong. A fe. thould ninor

oints in their description nay be orth a conrent.

1. ]orsible chnnges in the stable chlorine isetepec, C1 and 37C1, are centioned as a enans of distinguishing neteoric chlorine fron rock chlorine (pages, 34, and 10).

The citedonly on page reference I know to 3 (Desaulniers et any separation of these isoto)cs in nature al. 19f4). .

e one is th ascribed ,to long-continued diffusion. static ground.ater, in which n ve to the very different situation at Yucca Mountain.I don't see how this can have any applicat changes in the etable isotopes ic futile. Secos to ne that looking for 2.

to make porrible an ertinate of the chlorineBronine is to be added as a traci .

the wash water. that night be added to the sanples from fron the together withpowdered the AgC1. tuff along with the chloride and will gr be preci  ;

Craphic analysis of C1't Will the presence of Er have any effect on the mass-spectro-I doubt it, but maybe this should be mentioned.

3 On oage 9 in the of a few neters "nay be collected independently of the shaft mining I would be happier if t e sentence said "will be collected." .

ranples should be collected and run t .ru the nnalytical procedure Seens towell ne that such befor e the chaft irtern source started, both tochieride for neteoric check on details of the procedure and to ensure ethat th in well established.

4 to say that deeny data na;Seens to me the first paragraph on pageI 11 . readneeds it c]ar fron nore than one pulse of water novenent, that such an age would be o estinating rates of novenent, but no use in for the novement of pertechnetate ion.that it Seent night be useful in eniculating travel times will almost inevitably represent nixing of chloride ions from nany pulsesto . But I ne that a should think they predicting the possible nigration of Tc0 night ntill give useful information about water novenent as as we 4 .

Have I nicsed sonething in the logic?

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I Figure 14.--Generalized section across Yucca Mountain showing flow regime '

under baseline conditions. Lengths of solid arrows show relative magnitude of fluxes.

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