ML20137D455

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Requests That ACRS Consider Withdrawing OL Approval in Light of Serious Unresolved Safety Problems,Including Continued Abnormal & Differential Settling,Unknown Characteristics of saprolite-halloysite & Remedial Drainage for Groundwater
ML20137D455
Person / Time
Site: North Anna, 05000000
Issue date: 05/05/1977
From: Allen J
NORTH ANNA ENVIRONMENTAL COALITION
To: Okrent D
Advisory Committee on Reactor Safeguards
Shared Package
ML20136A555 List: ... further results
References
FOIA-85-363 NUDOCS 8508220489
Download: ML20137D455 (4)
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Text

' NORTH' ANNA E NIRONMENTAL COALITION P.O. BOX 3951 CHARLOTTESVILLE, VIEINIA 22903 Dr. David Okrent, Chairman (804)293-6039 North Anna subcomittee Advisory Comittee on Resctor Safeguards May 5, 1977 U. S. Naclear Regulatory Comission 1717 R Street Rocan 1046 Washington, D. C.

Dear Dr. Okrent:

Although the ACRS letter on North Anna was wr'itten on January 17, 1977, we trust that the Comittee is still cen-carned and open to the consideration of new infor=ation on the VEPCO power station in Mineral, Virginia. Further, the North Anna Environ = ental Coalition believes that Advisory Co=nittee on Reactor Safeguarda should consider withdrawir.g its Operating License approval for North Anna in the light g the fc11cwing serious and still unresolved safety probles:

1 Continued abnormal and differential settling.

  • RRC's April CONSTRUCTION STAWS REPORT notes as a construction deficiency at North Anna " sections cf the service water piping between the service building and Unit 2 main steam valve house were overstressed.

"Overstresses caused b'y differential settlecent of access road. Sections of affected pipe will be cut out and replaced."

Althcugh the ACRS letter of October 26, 1976, states that " future settlec:ent...shculd be cicdest," it would appear that the settlement situation is not yet under centrol and cannot be accurately or safely predicted.

2 Unknown characteristics of saprolite-halloysite.

Because the KRC had "little or no data on the cyclic response of a saprolite" (underlying many structures at North Anna) it requested saprolite analysis by the Army Corps of Engineers on Ifay 26, 1976.

That report was not received by the KRC until this past March 11 - almost two =enths after the ACRS letter. Surely the Comittee should study a report on a key facter in the " unexpected" settlement at North Annas compressibility and questionable bearing

. capacity of the saprolite.

8508220409 850722 PDR FOIA DELL 85-363 PDR

3 Remedial drainage required for excessive grcundwater.

In all eix supplements to KRC's SAFEY EVAlDATION RE?CRT of June 1976, groundwater control (necessary because of a 14' prediction error) was listed as i an " outstanding item" requiring a system of well po ints.

Well points has proved unsuccessful, and horizontal drains are planned for installation by Sentember 1, 1977 That would mean fuel-loading is planned almost 2 months prior (July 8,1977) to this experimer.tal safety system to help control still continuing ab.

normal and differential settling with censequent over-stressed piping.

The monitoring of groundwater levels, proposed .in VEPCO's letter of April 15, 1977, is certainly no i

safety solution for an overating plant. The record lant (See of 30 settlement Reports Nos.monitoring at the 50-200/75-1 and Surry 50-261p/75-1) gives '

no basis for confidence in the efficacy of care-ful monitoring at North Anna.

We believe the 40RS shculd question the basis for VEPCO's chcice of a grcundwater level of 285' as the

" threshold value for continued operation of the unit.

YEPCO's original analysis used a level cf 256' and its correction of March 15, 1976 or.17 " determined that .

it was possible for groundwater elevations to be as high as elevstions 4265.00' to 4270.00'within the station ares."

7Tsat is the significance of the additfor.a115'?

As you well knew, the Coalition's safety ccncerns rega.rding Kerth Anna are not limited to the above probles. Te believe that i

fuel pool capacity and projected increase raise serious .luestione along with these matters put before you by the Ccalition in August and October of 1976.

Nevertheless, for the Intrpcses of today's letter, w shall

'stop here, but include for your consideration and the.t cf the er..

tire committee the Coalition's letter of April 20 to ifr. Ernst l Vo1Cenau, Lirector of the KBC Office of inepection and Enforcasent.

Thank you for your professional interest.

Sincerely, June Allen (Mrs. Phillip :.!.)

President, NAD3 Enc. '

p uw N Februsry ll,1977 '

NORTH ANNA ENVIRONMENTAL COALITION' P.O. BOX 3951 CHARI4TTESVILLE, VI5GINIA 22903 VEPCO REACTORS 40% DEFICIENT IN DESIGN (804)293 6039 .

North Anna Reactors #1 r.nd 2 lack by 40% the minimum margin of safety M//~M in seismic design now recomended by the Advisory Committee on Reactor Safeguards ( ACRS }.

In its January 17 letter to NRC Chairman Marcus Rowden, the ACRS consultants

" recommended that, in view of th'e uncertainties of knowledge concerning the, sources of earthquakes in the Eastern United States, a minimuq safe shutdown earthquak,e_ (SSE) of OA ac-celeration should be utilized for new plants for which con-struction permit applications are submitted in the future."

Torth Anna's SS design is only 0.12g, just 60% of that recommended for future construction. Despite the acknowledged 40% deficiency, the ACRS letter found "the current design bases acceptable for the already constructed North Anna plants."

Tostimony at the January meet ing of the ACES. however, reveals some uneasi-ness about North anna's design:

Dr. Page: I really think '; hat in the future those (g) values should be larger... I think that we would all feel a little bit better if the g values were initially set higher... (pages 136-137 of 1/5/77 transcript)

Dr. Okrents ...with regard to auditing seismic design, I would myself rest less well-assured.. .that there are no scismic design errors. I don't know how you find them experimentally without the earthquake... (p.182)

Dr. J. Carl Ctopp, NHC seismologist, admitted that the Heusner spectra used in the design of North Anna Units #1 and 2 was "not corrected for Eastern U.S."

VEPCO SUSPECTED DESIGN DE/ICIENCY IN 1969 r

To make a reactor earthquake-resistant is expensive. VEPCO was worried in 1969 that the then AII: might require that North Anna's g level be raised from 0.12 to 0.15. Notes of a VEPCO meeting of August 20, 1969 reveal the utility's concern and proposed strategy:

"The AEI: is postalating for the Design Basis Earthquake at least a strong Intensity VII. (Modified Mercalli) near the site.

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VEPCO 8/20/69 meeting notes (cont.)

" tor an earthquake of that intensity close in to the site, the Housner reslonse spectra now being used for seismic de-siCn of the station could undere_ stimate the rosyonse to earthquake, t ground motion of some structural components.

"Since the DhL has questioned the use of the Housner spectra, we s_h_ould b_e_ cautious,n ,i_n, our discussions with, the _AliC, dth r,egajr to seism 3c des 13 values,_and grocedur,es...

...it might be advisable to accept, somewhat reluctantly, the higher values of .08 and .15g and avoid discusalon of the anlicability of the Housner resionne spectra..." NX-16, S.C. 3/74 Despite VEPCO's " reluctant" considoration of hit.;her g values, they were never implemented as indicated by the ACRS letter of January 17, 1977.

DESIGN DE/101ENCY IN N0hTH ANNA REACTOR #3 It has been known for some years now that all 4 North Anna reactors are constructed astride a wet clay-fillel fault. That fact may have n bearing upon the "Losign/ Fabrication Error" cited by the NBC in Unit #3

" Design deficiency. Lack of adequate s afety margin for earthquake forces and uplift forces due to water under

] s t ructu re. hcck anchors added to integrate foundation with rock.

"A desiCn deficiency of the containment auxiliary foun-dations would not prevent, with adequate safety margin,

~

the movement of the containment auxillary structures with respecIto thTcontainme'nt structure during a des!Cn basis earthquake, causing a possible bread (sic) (breach 7 break?)

of containment. A similar problem existed with service water intake structure." (NRC/LSt Output, M gt 20,1976)

The Coalition believa;that the presence of water in the foundation for Unit #3 raises questions about the conditions beneath Unite #1 and 2.

NAEC ruiued this issue before the Atomic Safety and Licensing Board in Charlottesville on November 30, 1976, at the first section of the Operating License hearing, and will ask for an answer when the hearing

  • reconvenes.

2

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