ML20034H244
| ML20034H244 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 01/22/1981 |
| From: | Malsch M NRC OFFICE OF THE GENERAL COUNSEL (OGC) |
| To: | |
| Shared Package | |
| ML18058B973 | List: |
| References | |
| FOIA-92-436 2.206, SECY-81-054, SECY-81-054-01, SECY-81-54, SECY-81-54-1, NUDOCS 9303160237 | |
| Download: ML20034H244 (41) | |
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January 22, 1981
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,e ADJUDICATORY ISSUE (Nota" ion Vote) i For:
The Commiss:.on Martin G. Malsch, Deputy General' Counsel From:
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Subject:
DIRECTOR'S DENIAL OF 2.206 RELIEF (IN THE MATTER OF VERMONT YANKEE NUCLEAR POWER CORP.)~
Facilitv:
Vermont Yankee Nuclear Power Station To inform the Commission a Director's decision
Purpose:
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pursuant to 2.2,0L which in our opinion,
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f Review Time Expires:
February 6, 1981 as extended t
Discussion:
By letter to Chairman Ahearne dated November 27, 1980, Ms. Virginia Callan and Mr. Cort Richardson 1/- i 1
requested that the Commission conduct a full,.public investigation into the opsration and safeYy"of,thei Vermont Yankee Nuclear Power Plant /J that"R~public ~ j tearing be held on the findings.of'. such. invest. iga
,, i tion, and that the f acility remain-' shut-down"until"'- l the requested investigation could be completed.
As of the date of Ms. Callan and Mr. Richardson's letter, the Vermont Yankee f acility was. shut down kf 4mation in this re ad was dMew for refueling and miscellaneous repairs.
The plant ~
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abrmab.Ehas been back in operation since late December.
Act, exemptions M A~ d -@l The petitioners' letter was' referred to the Office f
of Inspection and Enforcement for action pursuant to 10 CFR 2.206 of :the Commission's Regulations.
On December 15,1980, the Of fice Director and members l 1/
Ms. Callan and'Mr. Richardson's letter was sent to the Commission on behalf of several individuals and the Vermont Yankee Decommis-
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J sioning Alliance ( Attachment 1).
Contact:
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Patricia R. Davis, OGC, 43224 i
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q of his staf f met in Bethesda, Maryland with four representatives 6f the Vermont Yankee Decommission-ing Alliance, including Ms. Callan and Mr. Richardson
,to. discuss the issues raised in petitionggs' letter.
By decisiog of f y f' r
J' December 29, 1980 (Attachment 2), th denied all of petitioners' requests./;_D.1 rector Jy><fi In their letter, the petitioners' specified six issues which they felt raised questions about the saf'e operation of the vermont Yankee plant.
Each issue is listed below with the Director's response immediately following:
1.
Reactor Water Cleanup System cracks and Corrosion.
As a result of inspection findings which identified a number of pipe cracks in the Reactor Water Cleanup System, the Vermont Yankee management replaced all RWCU system piping inside the drywell, as well as the drywell penetration and the piping up to the first isolation valve outside_the dryvell.
The RWCU system is expected to, con form :to -
applicable regulatory requirements,and industry codes and is being 'inMpected:by;NRC rstaf f, to _ d-verify satisfactory completion of repairs.
In addition, the RWCU piping will be subject to continuous monitoring and inspection by licensee and even in the event of a complete break in the RWCU system piping, the emergency core cooling systems are capable of providing adequate cooling of the reactor core.
2.
Turbine generator shows signs of wear and needs repair.
During the 1980 refueling outage, Vermont Yankee inspected and made appropriate repairs to selected portions of the turbine generator unit.
Further inspections are scheduled for 1982, 1983 and 1984.
The program of repairs and inspections should avoid any safety problem 3.
Anchor bolt replacement.
Although Vermont Yankee identified deficient installations in the use of pipe support anchor
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'4 bolts, the deficiencies have been corrected.
The NRC continues to review the completed anchor bolt installations-through the ongoing
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routine inspection program.-
The petitioners also questioned:the' adequacy of other work completed by Hartwell Co. which~
was directly -involved with the initial' anchor bolt installation. - The Director'poncluded.
that these concerns are not warranted because tests and inspections conducted during. con-struction, during: normal' operating and transient conditions, as well under-the' Inservice Inspection program have not: identified - any-major breakdown in construction ~ QA/QC.
4.
Repeated failure-in attempts 1to repair Dry Well Torus emergency containment' system.:
In 1975, the NRC requested _ all owners' of Mark I ~l containment systems to make certain' improvementr 1 in order to restore original design; safety _
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margins.
The original safety margins had been reduced when additional LOCA loading conditions. !
vere identified.
Af ter study, Vermont Yankee made modificati.ons. _to. upgrade. its. system....
Indeed Vermont; Yankee -has ^ completed all ?correc-a tions required'as' par.t'of the.so-called,.long _
i term programT
- The - licensee 'will submit to -
the NRC an analysis. which will confirm the i
adequacy of-the modifications made to date or describe any supplementary modifications i
which may'be~ required.
5.
Vermont Yankee does not have an installed-F inerting-system.
A rule published in the Federal. Register by' the-Commission on October 2,1980: entitled._
" Interim Requirementsi Related to Hydrogen 1!
Control and _Certain _ Degraded Core-Consideration! !
(45 F.R. 65466) -would: require the Vermont.
Yankee to inert sometime af ter rulemaking is i
completed.
Requiring _ Vermont : Yankee tof inert; j
immediately would be very ' costly _ because 'iti l
would substantially extend 'the 'present shutdown j
period._ operation with deinerted containment is in accordance with the Appeal-Board's -
decision in ALAB-2 29, 8 AEC 425 ' (1974 ), and j
acceptable pending completion of _ rulemaking.
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6.
Operation without action by Vermont's Water Resources Board on Vermont' Yankee'.s application to review its waste discharge permit.
This issue is not.within the purview of. the f
NRC.
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Recommendation:
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l Martin G. Malsch Deputy General Counsel l
Attachments:
- 1. Callan and Richardson letter l
- 2. Decision l
i Comissioners' coments should be provided directly to.the Office of the Secretary by c.o.b. Thursday, February 5, 1981.
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Comission Staff Office ccmcnts, if any, should be submitted to the Comissioners i
29, 1981, with an inforr.ation copy to the Office of:the Secretary. _ If NLT January the paper is of such a nature that it requires additional time-for analytical review and coment, the Cornissioners'and the Secretariat should be apprised of
'i when coments r.ay be expected.
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WMt Decomnu.tY.ank.e Wrmon ssio111nt Alliancia Brattieboro Wrmont 053 127MainStae M-M46 John Ahearne, Cheirra n Nuclear Regulatory Co= mission
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Nove=ber o7, 1950.
Dear Chairnan Ahearne:
We are writing to you about a =stter cf grave concern and urcenev..
The Vernont Yankee Cuclear tower :Isnt in Vernen has been shutdorn since Septerter 77 fer re^ueling ind scheduled re-nrs.
Daring t:t "ast two scnths, a nn ber cf serious and unexrected :rnble=s -have su-faced at the f acility.
The plant.as scheduled to resume oper-Etiens en Neverber 99 but the e additional disceveries hsve ferced further delays.
We believe that there will be s real crd.inninent threat to huran life if Vermen-Yankee recpens.
Incicsed is a cc y cf a letter t.*.?t we =alled this week to Vernont rublic officials calline for "a full and ublic investigation into the operation and safetf of Ver=cnt Yenkec,~ ne have als o centacted our congressional delegation for tre puroose of involving the: in- - -
werking in cur behalf in this serious ratter.
7 Te ask that yoi: inunchis~uchJn[investiditicln: ichsiatelv in co-o eration with the state cf Ver=cnt e5d cIticens rcu s and'ihat "' "
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Enturally, we fully ex':ect ::s t :,5 ycu organise :nblic hearings.
- o. lant will remain closed fer the duratien of the investigatien A delegetien of our renbershir intends to visit you a:d your
.7e will contact your effice to staff next week in Tisshin-ten.
ar range a meetinE ti e.
We nis't all work to 6 ether in a ro: ot and ooen nanner to fore-.
stall the irr= vocable threat that Vermont Yankee coses to our I
besutiful region.
Sincerelv, g
Con diCka Vireinia Callan Cort. Richardson Ver5cnt Yankee Versent Yankee Decer issioning 1.111nnce Decc==issicning 111ance Kent-elier, Vt. 05502 3rattleboro, Vt. 05301
( EOP) 293-EE95 (502) 257-0072 cc. ;1111a= Dirks,. Dire ctor Safety and safeEsrds Division
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'gF Honorable R'ichard.A._Snelling
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.c State of Vermont, State House -
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Montpelie.
VT 05602 H
Tn0nt M 2 Honorable Richard Saudek. Chairman Vermont public Service Board Deconunissionir A
Vermont State Nuclear Advisory Panel
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Montpelier, VT- 05602
' 127.%in Str' Ilonorable Brendan J. Whitaker, Secretary lirattleboro Wrmont 0.~i i
Agency of Environmental Conservation 802 6 99 Montpelier, VT 05602 EmD17 5St5teStr Montpelier.Wnnont056
Dear Sirs:
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Mr.! 22W.:
Vermont lies in one of the most beautiful regions of 'our country.
The State governme'nt has enjoyed a long standing reputation of concern for the health of its citizens and for protection of its invaluabic natural resources.
We know that you share these concerns and that you will act in this tradition on the following matter.
This is a request for a full and public investigation into the operation of the Verment Yankee Nucicar Power plant. Recent disclosures-about new problems at the facility give us great reason for concern.
i in independent, sufficiently funded investigation into the safety and mana; ement of Vermont Yankee i.s in the public $nterest.
t We petition you and your respective agencies to exercise your' authority' to organize su'ch an* investigatice on the behnif of thousnnds,
of our supporters in this state, and'throughout the area adjacent to the plant.
We request, also, that public hearings-be held on this important matter.
We ask that you seek the full. cooperation,and m.
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participation of the Nuclear Regulatory Commission as well as independe' experts in this effort.
Most importantly, you should use the emergency J'
powers available to you to ensure that the plant will remain c1cced dur:ng this process.
On September 27. Vermont Yankee shutdown for maintenance, repairs and refueling.The plant was scheduled to re-open on November 20. I n st e r.
a number of new problems have surf aced which require repniis or re-placement.
These discoveries have delayed the. re-opening of the pinn for nn undetermined period of time.
Cracks and corrosion have been discovered in components or the pinnt's water cleanup system including a-sax;y foot section of.the j
very important reactor. water dischar;;c pipe. It is not clear what caused this unexpected f atigue in such a critical nren o f the -plant.
This is very serious.
.potentin11y.such insufficient-nrotect$on la an important section of the primary conling system could cau:sc n 1oss l
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of coolant in the reactor resulting in immed$ ate danner to the public.
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This situation should be a central part of the investiention into j
p2 ant management and snfoty.
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t The f aci]ity'.s turbine generator al:m showed.ninns of si;:n t ri-cant wear and will require repairs.
A turbine n; the Yankee Atomic j
plant in Rowe, Massachusetts in similar condition caused that plant l
to be closed for most of this past year when it literally fell apart during an attempted start-up.
Apparently the corrosion and stress sustained by these systems combined with po.ss2bly poor design and workmanship have contributed to accelerated decay and 1
unreliability.
The Vermont Yankee Nuclear Power Corporation is currently seekir to recover their expensea from the costly replacement of defective i
bolts in the piping support system resulting from their original and possibly fraudulent installation.
Can we reasonably assume that Vermont Yankee can be reopened when the bolt issue represents the latest in a history of improper operation, unexpected repairs, and unscheduled and extended shutdowns?
The history of the Dry We11 ' Torus e=t rgency containment system currently under repair at Yankee, is one cf repeated and costly failures in repair attempts, resulting in years of operation without the full benefit of this critical safety system.
The f act that there have been repeated leaks in the plant's cooling systems has added to -
danger of a life-threatening accident because the torus was designed to back-up those systems in the event of a major loss of coolant acc:
Vermon: Yankee is the only plant in the country that refuses to install an inerting system, even though the N.R.C. has advised them to instn11 one.
This safety unit would fore. stall hydrogen in the event
. explosion that would breach the reactor containment of an accident.
The plant has been allowed to operate since last June without any f urther action from Vermont's Yater Rescurces Board on the At a publi-company's application to renew its water discharge permit.
was held in Brattleboro that month, many questions hearing that and objections were raised and the permit was held back for 2.dditione s t u dy..
Unicrtunately, the plant has operated since that time under the old permit even though it did not comply with the terms of its t
contract with the state.
These events cannot be ignored.
There is a serious and immedin danger to the people of our region if Vermont Yankee reopens without a thorough investigation.
It is our belie! that these aforementionec prob 1 cms constitute the most extreme and immediate threat to public saf ety that Vermont Yankee has over posed.
52ncerely,
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,.lll Chris Wood
/ John Warshow Vermont Yankee Decom-Central Vermont.
Safe Inergy Coalition missioning Alliance I
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Il UNITED STATES NUCLEAR REGULATORY COMMISSION DOCKEi NO. 50-271 VERMDNT YANKEE NUC; EAR PO*ER CORPORA; ION (VERMONT YANAEE NOCLEAR P0wER STATION) 1550ANCE OF DIRECTOR S DECISION UNDER j
10 CFR 2.206 Ms. Virginia Callan and Mr. Cort Richardson by letter cated November 27, 1980,'
on behalf of the Vermont Yankee Decommissioning Alliance, as well as several l
,7 other indivicuals,2 have recuestec that the Commission conduct a full and public investigation into the ope-ation and safety of the Vermont Yankee Nuclear Power Plant, that a public hearing oe hele on the findings of such 2,' ntil the requested i
investigation, anc that the facility remain snutcown u
investigation and hearings are completec.
Ms. Callan anc Mr. Richarcson's letter has been treated as a request for i
action uncer 10 CFR 2.205 and nas been referred to the Commissions Office of
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Inspection and Enforcement.
Upon review of this matter, the' Director has -
ceterminec that resumption of power c;eration of the named facility will net je:parcize public health anc safety and that a full and public investigation-into the issues raised by Ms. Callan and Mr. Richardson is not warranted.
Accordingly, the request has been denied.
3.
2'Rancolph Wilson of South Royalton, Vermont; Leslie J. Dowling of Brattieboro, Vermont; Lisa Limont and others on behalf of the Ad Hoc Citizens Group for Safety at Vermon: Yankee, of Greenfielc, Massachusetts, MacNeil of Greensboro, i
Vermont; and Jean V. Lowell of Hollanc, Vermont.
nfd' As of ine date of Ms. Callan and Mr. Richarcson's letter, the Vermont Yankee facility was shutdown for refueling and miscellaneous repairs.
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Copies of the Director's decision are availacle for inspection in the Commission's Public Document Room,1717 H 5treet, N.W., Washington, D.C.
20555 anc at the Brooks Memorial Library, 224 Main Street, Brattleboro, Vermont 05321.
A copy of the decision will also be filed with the Secretary for the Commission's review in accorcance with 10 CFR 2.206(c) of the Commission's regulations.
i As proviced in 10 CFR 2.206(c), the cecision will constitute tne final action of the Commission twenty-five (25) days af ter the cate of issuance, unlest the Commissior., on its own motion, institutes a review of the decision within that time.
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R. C. f,g Y
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veYoun Acting Director #
Office of Inspection anc Enforcement Datec at Seinesda, Maryland this;* day of Decen. Der, 1980 i
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UNITED STATES OF AMERICA-NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT Victor Stello, Jr., Director I
In the Matter
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Vermont Yankee Nuclear Power Corp.
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Docket No. 50-271.
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Station)
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DIRECTOR'S DEC5510N UNDER 10 CFR 2.206 Ms. Virginia Callan anc Mr. Cort Ricnardson, by letter to Chairman Ahearne, dated November 27. 1980, on benalf of the Vermont Yankee Decommissioring Alliance, as well as several otter indivio'uals,1 have requested that-the
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Ccmmission concuct a full and public investigation into the operation and
, safety of tne Vermont Yankee Nuclear Power Plant, that a public hearing be held on the findings of such investigation, and that the facility remain shutdown ! until the requested investigation a7d hearings are completed.
Ms. Callan anc Mr. Ricnaroson's letter has been referred to the Office of Inspection anc Enforcement for action pursuant to 10 CFR 2.206 of the Com-mission's Regulations.
Ms. Callan and Mr. Richardson contend that recently a number of serious and unexpected problems have surfaced at the Vermont Yankee facility.
1/Randolph Wilson of South Royalton, Vermont; Leslie J. Dowling of Brattleboro,
~ Vermont; Lisa Limont and others on behalf of the Ad Hoc Citizens Group for Safety at Vermont Yankee, of Greenfield, Massachusetts; MacNeil of Greensboro, Vermont; and Jean V. Lowell of Holland, Vermont.
2/As of the date of Ms. Callan and Mr. Richardson's letter, the Vermont Yankee facility was shutdown for refueling and miscellaneous repairs.
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Director's Decision 2
t Their letter states that "there will be a real and imminent threat to human life if Vermont Yankee reopens." Specifically, they allege that cracks and corrosion in a sixty foot section of pioe in t..e plant's water cleanup system i
have recently been discovered; that the facility's turbine generator showed signs of significant wear and will require repairs; that the recent replacement t
of a large number of bolts in the facility's piping support system raises con-cerns aoout the safe operation of the f acility; that the Dry Well Torus emergency containment system has a history of repeated and costly failures in repair attempts "resulting in years of operatien without the full benefit of this critical safety system"; that Vermont tankee is the only plant in :ne country that refuses to install an inerting system; and finally that the plant has been aliewet 10 c;erate since "last June" without any further acticn.from Vermont's Water Resources Board on the company's application to renew its water discharge permit.
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On December 15, 1980, tne Office Director and mercers of his Staff, met witn four representatives, including Ms. Callan and Mr. Richardson, of the i
Vermont Yankee Decommissioning Alliance in Bethesca, Maryland to discuss the i
issues raisec in Ms. Callan and Mr. Richardson's letter.
After consicering the requests, for the reasons set forth below, I have con-cluded that a full and public investigation into the issues they raise is not warranted and that the public health and safety does not require that the Vermont Yankee facility remain shutdown.
Accordingly, I have determined not to grant the requested reiief.
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i Director's-Decision 3
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All of the issues which Ms. Callan and Mr. Richardson cited in their i
letter had been icentified previously anc are being resolved on a generic basis.
The letter contained no new information or safety concerns unknown to '
the NRC.
The five issues raised by Ms. Callan and Mr. Richardson's letter T
that are within NRC jurisdiction are discussed in detail below.
Findings and i
actions taken Dy the licensee and the NR; are adcressec.
The sixth' issue, rega-cing action of the Vermont Water Resources Board, does not lie within the purview of the NRC, and toerefore is not at:ressed in this decision.
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Reactor hater Cleanup System Cracks anc Recair Ms. Callan and Mr. Richardson's lette" alleges that " cracks and corrosion have Deen ciscovered in components of.tne plant's water cleanup system nclucir; a sixty foot section of the very important reactor water dischaege pipe." They contenc that these cracks and corrosion have the potential i
fer causing a loss of coolant in the *eacter that would result in imnediate danger to the public.
i ine reactor water cleanup (RWCU) system installed at the Vermont Yankee (VY) plant is not a nuclear safety related system.
It functions neither to provice cooling for the reactor core nor to mitigate the consequences of any of the analyzed accidents consioered in the facility design.
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Director's Decision 4
l design function of the RWCU system is to provide purification (cleaning) of reactor water, which is accomplished by continuously removing a portion of the reactor water and processing it through filter demineralizer units to undergo mechanical filtration and ion exchange processes.
Except for an approximate 60 foot length of piping and two associated valvesLiccated' inside the crywell containment, all other RWCU system piping and components are located outside the drywell and are subject to routine visual surveil-i lance during plant operation.
The visual surveillance, together with i
leakage monitoring instrumentation, provice assurance of early detection of a leak snoulc one occur.
Tne RW:V system piping inside the drywell provices the tap-off point from which reactor coolant water is taken to l
te processec.
This piping and associacec isolation vaJves are a part 'of i
the reactor coolant system pressure beuncary., This portion of.RWCU 1
piping, along with all other piping insice the drywell, is subject to continuous monitoring by leakage detection instrumentation.
(Limited.
i access to the cry. ell pronibits routine visual surveillance of RW:U piping during normal plant operations.) The drywell leakage monitoring i
systems provide assurance of leak icentification at an early stage so that proper corrective actions can be taken well before leakage becomes sufficient to compromise the reactor coolant barrier integrity.
f A further point should be made to bring into perspective the problem of cracking in RWCU system piping.
One could postulate, in spite of assurance of leakage detection capability provided by routine surveillance and leakage monitoring systems, that a complete break (severance) occurs in i
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Director's Decision 5
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the 4 inch diameter RWCU piping inside the drywell.
The emergency core cooling systems (ECCS) installec at the VY plant are capable of providing i
acequate core cooling and protection for a spectrum of pipe break s12es, up to and including the break of a 25 inch diameter recirculation system i
pipe.
The complete loss of a 4 inch diameter RWCU system pipe is'well within the capability of and protection afforded by the ECCS and thus, no i
t danger to the health and safety of the public should occur.
Notwithstanding the above, the integrity of the RWCU system, alon; with all other piping attachec directly to the reactor coolant system, is of inportance.
To provide additional assurance of piping. integrity, or conversely, to provide assuran:e that cegracation of piping integrity is icentified well before significant leakage could develop, all reactor
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coolant system pressure boundary piping inside the drywell, including RWCU system piping, is subject to inservice' inspection (ISI). -The ISI program is performed in accordance with industry codes and stancards.
For Vermont Yankee the governing Coce is tne American Society of Mechanical
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Engineers Boiler and Pressure Vessel Coce,1974 Edition,Section XI Rules for Inservice Inspection of Nuclear Power Plant Components. This provides a systematic means of inspecting reactor coolant system piping.
Inspec-tions conducted under the ISI program employ techniques, such as radiography j
and ultrasonic examination, capable of detecting pipe cracks at the i
incipient stage of development, well oefore they could be detected by visual observation with the unaided eye.
The ISI program schedule is e
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l Director's Decision 6
l established such that all reactor coolant system piping is inspected within a ten year interval.
The ten year interval is then divided into three inspection periods, with inspections conducted yearly within each period, usually during an annual refueling outage.
Development and implementation of an ISI program, as well as reporting the results there-~
from, are a condition of the VY license to operate.
Implementation of the ISI program at VY is routinely inspected by the NRC's Office of Inspection anc Enforcement, Fegion.I.
The inspections include a thorough reviev of the ISI program and procedures, witnessing of a portion of the ISI work in progress, verification of compliance with program require-ments and review of program inspection resuits.
The latest series of NRC inspections of the VY ISI prograt started in September, 1980 (see NRC.
Region I Inspection Reports 50-271/ S0-15 anc 50-271/80-20.)
The ISI program inspections conducted by VY during the 1980 refueling outage constituted the first inspection of the third perioc in the first ten year interval, as prescribed by Section XI of the Code and Section 50.55a of the Commission's regulations.
During this inspection, VY personnel identified cracks in several welds located in a 60 foot section of the RWCU piping inside the drywell.
The initial inspection findings t
were reported to the NRC in accordance with licensee requirements (see VY licensee event report, LER 50-271/80-37).
Continued inspection of the subject piping over a two week period ultimately revealed six welds with cracks, out of 17 welds inspected.
The cracks were located in an area
Director's Decision 7
called the heat affected zone of the weld, which is at the weld to pipe metal interf ace.
Heat affected zones of welds have historically (industry-wide) been susceptible to cracking due to a number of factors, including pipe material content, induced stresses, and sensitization of the metal during welding.
An additional, seventh crack was found on the surface of a "sweepolet" (a piping component that provides-a transition point from the 4 inch RWCU pipe to a 20 inch pipe).
This seventh crack was located in a high stress area of the sweepolet.
As a result of ne inspection fincir:gs anc cue to the extensive number of defects identifie:, VY plant manacement cetided to replace all RWCU system piping inside the drywell, as well as the cryseil penetration and This the piping uo to the first isolation valve outside the drywell.
approa:5 was taken instead of one involving identification and repair of each individual. defect, and is considered conservative.
A pipe replacement program was developed and implementec oy VY personnel. The pipe reolacerent program became the most time limiting work item in comparison with all other outage maintenance work anc ultimately extended the length of the recent outage beyond the scheduled completion date.
NRC Region I ISI Specialists were onsite for the routine inspection of the ISI program when the RWCU system cracks were first identified by the (Had the Regionai insoectors not been onsite, a special licensee.
inspection would have been conducted as a result of the finding of cracks
. j i
Director's Decision 8
in the RWCU system.)
In addition to completing a review of the routine program, tne Regional inspectors closely followed developments in the RWCU crack problem.
The review inclucec:
independent evaluation of weld raciographs, review of the bases for additional weld inspections once the initial defects were found, and review of the piping replacement program, including procedures and techniques used, quality controls applied, and inspe: tion of activities in progress.
Inspection of the area by Regional Specialists was conducted over foun separate special inspection trips of one week each during the period frem September 29 to November 21, 1980.
Witnin :ne scope of tne areas reviewec, no noncompliances or deviations f rom incustry codes or NRC regelations were identified.
It should also ce noted that VY management developec anc maintained the initiative in l
selecting the preper alternatives for corrective actions throughout the develcpment of the RWCU crack problem.
l 6
NRC Staff compared the VY ISI findings to the criteria established in NUREG-0313, Rev.1, Technical Report on Material Selection and 5
Processino Guidelines for BWR Coolant Pressure Boundary Pipino, dated 1
October 1979.
NUREG-0313 summarizes tne NRC Staff findings and conclu-sions regarding the occurrence of intergrannular stress corrosion cracking (IGSCC) in BWR piping systems, and presents methods acceptable to the Staf f for repair of pipe cracks.
Upon comparison with the NUREG-0313 criteria, the staff consicers tne most likely cause of the VY RWCU system pipe cracks to be IGSCC, in that:
(1) the factors necessary to cause i
i
i Director's Decision 9
i
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i i
IGSCC were present in the RWCU piping at VY, and (2) previous incustry-wide history of IGSCC in RWCU systems has caused the RWCU pipes'to be classified as " service sensitive" lines.
Final confirmation of the pipe crack mechanism will be obtained once the metallurgical analysis results from samples of the affected welds are available.
The licensee will i
i report the analysis results to the NRC Staff for review.
In accordance t
with NUREG-0313, one repair plan acceptable to the Staff consists of replacing existing service-sensitive piping with corrosion-resistant l
piping whose material constituents are controlled within specified limits.
VY mar.agement inf:rmed the NRC staff in a letter datec N0vember 10,195C that the RWCU repair would be completec with material conforming to NUREG-0313, Rev. 1.
Th'.s f rmal co mitment was acknowledged in an NRC letter to VY cated Decemoer 12, ISSO.
i As a result of the completion of RWCU system repairs by VY in the manner cescricec above, ine RWCU system piping is expected tc be in conformance with applicable regulatcry requirements and incustry coces.
Actual repairs were complete as of 12/17/80.
Satisf setory completion of VY actions in this area is being verified by the NRC inspection staff as part of the routine inspection program.
i i
In sum, the problem of cracks in Vermont Yankee's RWCU piping system raised by Ms. Callan and Mr. Ricnardson has already been addressed by the licensee and the NRC.
The piping system has been replaced by the licensee i
Director's Decision 10 p
and will be reviewed by NRC inspectors.
In addition, the RWCU piping system has bean, and will continue to be, subject to continuous monitoring and inspection for leaks.
Finally, even in the event of a complete break in the RWCU system piping, the ECCS would afford adequate cooling of the reactor Core.
In view of the preceding, I conclude that additional " full and public investigation" into the problem of cracks and corrosion in Vermont Yankee's RWCU piping system is not warranted.
In addition, Vermont Yankee's actions with respect to the RWCU system are in conformance witn its.
i license anc thus, in the absence of some safety issue, a basis coes not i
exist for preventing the facility from resuming operation.
t 2.
Vermont Yankee 1980 Refueling Outage Turbine Generator Activities l
Ms. Callan anc Mr. Richarcson have also allegec that Vermont Yankee's f
turbine generator shows signs of significant wear and will require repa' 1.
t The main turbine generator system converts the energy of the steam prod :e:
i t
~
by the reactor into electrical energy.
The turbine generator is not a i
nuclear safety related system, and it functions neither to provide cooF V -
for the reactor core nor to mitigate the consequences of any of the i
accidents considered in the facility design.
[
j Director's Decision 11 During the 1980 refueling cutage, Vermont Yankee performed inspection of
)
selected portions of the turbine generator unit in accordance with routinely scheduled maintenance and in order to establish a data base on turbine condition.
In this regard, Information Notice (IN) 79-37, Crackino in Low Pressure Turbine Discs (12/31/79), was forwarded to Vermont Yankee providing notification of a possibly significant matter in that embedded cracking in keyways and disc base areas had been observed in Low Pressure t
(LP) turbines manuf actured by Westinghouse Co.
Although Vermont Yankee utilizes a turoine generator unit manuf actured by General Electric, (GE) l ine NRC staff notifiec all hoicers of f acilicy cperating licenses arc i
i recuestec consiceration of the identified problem.
Vernont Yankee currently l
mantains a turcine generator inspection anc mainter.ance schedule such that eacn component is servicee at intervals of 3 to 5 years.
Based on the manufacturer's (GE) recommendation and the concerns expressed in l
IN 79-37, an accelerated inspectio~n effort was Yt'he'duled for the 1980 refueling outage.
As part of the turbine generator unit inspection, the following compenent areas were addressed:
Journal bearine insoection - The journal bearings support the weight of the turbine shaft and provide a bearing surface for shaft rotation.
The bearings consist of a metal ring lubricated by the turbine generator luce oil system.
The bearings are custom fitted to the shaft since the shaft 2
l,
.e i
Director's Decision 12 i
actually " bows" due to its weight and does not in all cases provice a
- flat bearing surface.
Inspection of No. 6 bearing by the licens,ee revealed i
uneven wear.
The bearing was sent to a-contractor for machining to provide for proper rotor seating.
The bearing was' subsequently reinstalled.
t t
Turbine erosion (water wear) i As the steam supplied to a turbine
- progresses through the turbine, the l
thermal energy content of the steam is transferred to the turbine as r
rotational energy and increasing fractions of the steam condense to water.
The water initially appears as droplets entrained in the fast moving steam, and containing enough kinetic energy to have an erosion effect as they impact metal surfaces.
This is a well known ' condition,
~~
which all turbine manufacturers and operators recognize. Turbines are desic,ned and built with provisions to ' rain'off the ' water collected.
d Nonetheless, water erosion does, and will continue to occur, anc monitt-ing it is a regular maintenance item.
One frequent location for water wear' is the keyways of low pressure turbine wheels, with the erosion track continuing radially across the wheel hub.
Indications of this conditic.n were found on tne 2-6 wneels of the A-low pressure turbine, and on 2-E wheels of the B-low pressure turbine.
The extent and depth of the eros 'on was measured by ultrasonic techniques, and analysis was performed to-predict the future growth of these areas.
An analysis considered the.
F1 ar present size, the rate of attack, and the stream field in the area.
I i
e
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Director's Decision 23 l
this, GE forecast conditions six years of operation later. _Using con-
)
i servative (rapid) growtn rates and comparing these 6 year later depths with the " critical" depth at which concern would arise for rapid failure, GE predicted that the erosion at the most critical location would be about 37% of allowable depth.
i GE recommended that the licensee conduct another inspection of the water wear in the turbine wheel keyways i,n 6 years.
Vermont Yankee now plans to inspect the hign pressure turbine in 1982, one low pressure turoine in 19E3, and the other low pressure turbine in 198c.
Other areas where wate-or steam erosion were found incluced steam headers, crossover piping and the low c essure turbine innercasing.
Where the depth of erosion caused the minimum wall thickness to be approached, wall thickness was restored by weld metal Duilcup.
Tnis is a well estaclisheo
~
and accepted method of repair.
Vermont Yankee cecicec that future erosion could be better controlled by a change in the material of the crossover l
Two piping from a copper bearing material to a nickei bearing material.
of the pipes were replaced during the ' current outage, and the other two j
are scheduled for replacement during the 1981 outage.
Inspection of turbine discs and blading revealed a cracked blade in the eignth stage of the A-low pressure turbine.
The blace was removed, and a blade on the opposite side was shifted to maintain symmetry and balance.
h f
i 2
1
14 Director's Decision
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The licensee concluded that this crack represented an isolated, random occurrence and was not a precursor of other failures.
rva-In summary, I find that Vermont Yankee has responced properly and conse tively to concerns expressed by the NRC in IN 79-37, and to the results Therefore I find that there is no of other planned turbine inspections.
l basis for conductinc an extensive public investigation and hearing on t.he subject of turbine integrity.
Anchor Boit Replacement 3.
Ms. Callan and Mr. Richarcson's letter als: alleged that a large number of bolts in the f acility's piping _ support system had recently been repr acee l and tna; such replacement raised serious cuestions concerning the safe l
f operation of the plant.
While performing routine inservice inspections at the Millstone Unit 1 power plant in Waterford, Connecticut during the Spring 1978 refueling i
outage, the plant personnel identifiec structural f ailures of piping-Subsequent licensee inst ec-supports installed on safety related systems.
tions of undamaged supports showed a large percentage of concrete anche :r t
bolts associated with the suoports that were not tightened properly.,
l These findings were reported to the NRC.
Subsequently, the licensee of -
the Shoreham power plant on Long Island, New York reported deficiencies '
f
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Director's Decision 15 i
it had icentified concerning the cesign of base plates used in piping j
system supports.
The deficiencies involved rigic plate assumptions used j
in the design of anchor bolt installations.
Further NRC review at Architect f
Engineering (A/E) firms (the organizations principally involved in anchor l
t bolt design and installation) showed a wide range of design practices and installation procedures used in concrete anchor bolt installations.
The NRC determined that current trends in the industry are to employ more rigorous controls and bolt installa, ion verifications than had been
[
t applied previously.
In recognition of the safety significance and potential generic applic-ability cf nis information, the NR: issuec IE Eulietin 79-02 on Marcn E, 1979 to establish the NRC's findings in the area and reouire that certain l
actions be taken to determine the status of anchor bolt installations at all power plants.
As further information was. received by _the NRC f tom.
licensee responses to the Sulletin, su;;iements to Bulletin 79-02 were issueo (Revisien 1 on June 21, 1979 anc Revision 2 on November 8, 1979) i clarify certain reouirements anc te direct that accitional actions be l
The major work effort associated with Bulletin 79-02 developed e
along two paths:
)
(1) test and qualify or replace ancnor Dolts installed on plant safety related systems to assure original design requirements were met; and i
5 i
Director's Decision ~
16 f
(2) re-evaluate certain assumotions used in the seismic analyses to define piping and support system design loads.
Issues related to the seismic design analyses ceveloped_during the 1978-1979 period and led to the issuance of further Bulletins by the NRC (IE Bulletins 79-04, 79-07, and 79-14).
NRC staff efforts were consolidated to review the anchor bolt and seismic issues together in '.979.
Vermont Yankee cevelopec a testing and analysis program to address NRC Bulletin requirements on seismic and ancnor ooit issues.
The program to verify the aceouacy of installed anchor bolts _ began in mid-1979.
After icentifying ine types and locations cf sucocris on all seismic piping systems, cefining suitable ctsign acceptance criteria, and developing test and inspection procedures, testing of installed anchor bolts at Vermont Yankee began in July, 1979.
Testing consisted of torquin~g or- -
ioad tensioning the ancnor belts te specifiec limits to determine whether the bolts coulc maintain prescribed loads.
The installation of each ancher bolt was also inspected and compared to stringently defined
-i installation criteria that included depth of embedments, location and length, dimensions, threac engagement and various gap distances and.
clearances.
Testing of bolts began in areas in the plant readily accessible during normal plant operations and continued for all plant areas during the 1979 refueling cutage.
t
Director's Decision 17
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a i
Bolt testing completed by mid-August 1979 revealed instances of f ailure c
to meet testing anc inspection criteria at a rate in excess of pre-establishec limits.
A small percentage (5%) of the bolts tested were found loose, but could be tensioned to above oesign loacs, however, it was noted that for the "as found" installation, a larger percentage of the bolts failed '
,one or more of the other inspection criteria.
Inspection of the support installations continued, but testing was stopped.
Instead, a program was begun to replace all slide type anchor bolts with bolts of an improved design and to correct installation deficiencies.
By October, 1979 the scope of the replacement program level had oeen refinec~ to include 450 pipe supports containing 2500 anchor bolts.
By the end of the 1979 re-fueling outage, one half of the total numoer of supports hac Deen modified.
This encompassed all supports normally inaccessible during plant operations.
a All anchor bolts were replaced and bolt installation ~s~ brought into total conformance with design criteria by the Spring of :.950.
The NRC staff closely followed licensee actions in this case through reports submitted by VY, meetings held with licensee staff and through NRC inspections performed as part of the routine inspection program.
NRC inspectors reviewed the development of the initial test / inspection program, development of the bolt replacement program, activities of work in progress, and completed bolt installations.
Any identified installation deficiencies that had the potential to impact adversely the operability of a piping system were corrected expeditiously.
Instances of this-type were specificall3
?
4' Director's Decision 18 In no reported to the NEC by the submission of licensee event reports.
case did a loss of system operability occur.
t NRC inspection of the licensee's bolt inspection and test results identified only a fee instances (less than 6) in which a bolt head was tack welded i
to a base plate with the bolt shank cut off or missing.
Deficiencies of this type involvec one bolt out of several installed in any given size All other deficiencies involved deviations from bolt installation support.
criteria or deviation from a specification.
Some deficiencies also inveived brcken or camagea colts.
Factors centributing to these deficiencies could have included (but are net limite: t:): inadequate quality controls applie: during original support /ocit i'.stallation; less stringent crite*ia cefinec for initial installation when compared to the criteria'in current industry standards; difficulty in performing the initial installation cue to physical constraints (such as support location and/or. limited...
accessicility); worker carelessness; and insufficient cesign.
NRC review of the completed anchor bolt installations, as well as the seismic analysis program, is ongoing tnrough the routine inspection program.
The company directly involved with the initial anchor bolt installation was tne Hartwell Co., under contract to Ebasco, the Architect / Engineer
( A/E) for initial plant construction.
Under contract no.
NY-706116,
Director's Decision 19 I
i Hartwell was responsible for " furnishing material, fabricating and erecting the complete power plant piping system, in:1udirg related hangers and i'
supports." Ms. Callan and Mr. Richardson raised concerns questioning the l
aceouacy of other work conducted by tnis company.
These concerns are not warranted for the following reasons:
NRC inspections during the plant construction period, while done uncer a sampling program, showed with a high degree of confidence that no major breakccan in the constructicn QA/QC area o::urred. In
- a-ticular, no major QA/QC preolems were icentified in regarc to i
reactor coolant pressure bocncarj and/or safety system piping installa-tions.
t Tests conducted under the Te:nnical Specification su'rveillance program on plant safety systems nave-demonstrated system operability -
(and hence piping integrity) uncer both normal operating ano transient conditions.
Tests conducted under the Inservice Inspection program have not identified deficiencies that would be attributable to improper ccnstruction QA/QC.
I In summary, although deficient installations have been identified in the use of pipe support anchor bolts, the deficiencies have been rectified.
h i
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Director's Decision 20 Past NRC inspection findings in the area of piping and support installa-tions de not support contentions of generic fraudulent installation l
practices and concerns of present operation in a degraded safety condition.
Consecuently, I have determined that further investigation into the bolt replacement problem is not warranted and that there is insufficient cause' l
to prevent the VY plant from resuming power operation.
4 Torus Modifications I
Ms. Calian anc Mr. Ricnarcson allege ina; there have teen repeatec failures in attemcts to repair Vermont h ankee's Dry well Torus emergency containment syster anc nat the system is again un:e r:ing repair.
Ms. Callan and i
Mr. Ricnarcson contend that these pro:.iets increase tne danger of a e
life-threatening accident at the f acility since the torus system was designec to serve as a-back-up to the plant's primary cooling system in the event of a loss of cociant accicent.
Vermont Yankee utilizes a Mark I or "crywell-torus" primary containment design.
Tne Mark I design is a pressure suppression type and is made up
[
of a drywell in the shape of an inverted light bulb connected via vent pipes to a torus shaped suppression pool.
The objectives of the primary containment system are, in the event of a cesign basis loss-of coolant accicent (LOCA), te prevent the release of fission procucts to the environ-mentine$cessofthefederallimitsspecifiedin10CFRPart100,to l
1 f
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Director's Decision 21 r
provide pressure suppression, and to provide a source of water to certain Emergency Core Cooling Systems (ECCS).
l The suppression chamber is a steel pressure vessel in the shape of a l
torus, located below and encircling the drywell.
The suppresssion chamoer i
is held on supports which transmit vertical and seismic loading to the l
reinforced concrete foundation slab of the reactor building.
Eight circular vent pipes connect the dryyell and the suppression chamber.
The 4
pressure suppression chamber serves not only as a neat sink for blowcown from the drywell after an accident but also as a source of water or heat t
sink for the following ECCS functions:
1.
Core spray injection anc testing.
2.
Low pressure coolant injection mode of resicual heat removal (RHR)'
l and testing.
2.
High pressure coolant injection (HPCI) an: reactor core isolation cooling (RCIC) pumps alternate source of water.
'~
t 4.
Heat sink for steam blowdown from safety / relief valves.
i 5.
Heat sink for HPCI and RCIC turbine exhaust steam.
The first generation of General Electric (GE) EWE nuclear steam supply systems are housed in a Mark I containment system.
A total of 25 B'dR
[
r facilities with the Mark I containment system have been or are being built in the United States; of these, 22 are licensed for power operation.
i The original design of the Mark I containment system concidered postulated accident loads previously associated with containment design.
Since the i
Director's Decision 22 establishment of the original design criteria, additional loading condi-tions have been identified which arise in the functioning of the pressure suppression concept utilized in the Mark I containment system cesign.
These additional loads result from the cynamic effects of drywell air and i
steam being rapidly forced into the suppression pool (torus) during a postulated LOCA and from suppression pool response to safety / relief valve (SRV) operation generally associated with plant transient operating 4
conditions.
Because these loads had not been considered in the original cesign f the Mark I containment, the NRC determined tnat a detailec reevaluation of the Mark I containment system was required.
In February anc April,1975 the NRC transmittec letters to all utilities owning EWR facilities with Mark I containment system cesigns recuesting.
the owners to quantify the hydrodynamic loads and to assess the effect of these loacs on the containment structure.
The utilities formed a Mark I owners group and GE was designated as the Group's leac tecnnical organi:a-tion.
The objectives of the Group were to cetermine tne significance of the loads and identify courses of action neecec to resolve any outstancing safety concerns. The task was divided into two programs, the short-term program (STP) and long-term program (LTP).
The objectives of the STP were to verify that each of the Mark I containment i
systems would maintain its integrity and functional capacility when i
subjected to a postulated' design basis LOCA, and to verify that licensec
e Director's Decision 23 Mark I BWR facilities could continue to cperate safely without endangering the health and safety of the public, while a comprehensive LTP was conductec.
The STP acceptance criterion (a safety-to-failure factor of 2) was used to justify continued operation of each plant.
The NRC concluded in NUREG-D40S that a sufficient cargin of safety had been demonstrated to assure the functional performance of the containment and, therefore, no undue risk to the health and safety of the publit existed at Vermont Yankee.
Subsecuently, the staff granted tne operating Mark I facilities exemotions relative 1 tne structural factor of safety recuirements of 10 CFR 50.55(a).
Inese exemptions were granted for an interim period while the comprehensive LTP was being conductec.
Tne licensee committed to a long term program to upgrade the Mark I torus from a safety factor of 2 to a factor of 4.
At no time did the licensee operate witnout tne full benefit of this system.
In July of 1975, Vermont Yankee commencec modification of the tores supper column to torus shell connections as part of tne LTP to strengtrer the connections.
Since the modifications were being performed while the plant was in operation, the attachment of gussets to the outer shell required welcing in areas wnere tne torus shell had water on the opposite I
side.
A special weld procedure was cevelooed and qualified.
As a precac-tion, noncestructive examinations (NDE) were performed during welding c' the pads.
NDE revealed surface cracks in the base metal after the gussecs
+
Director's Decision 24 had been partially or completely welded to the pads.
The licensee ceveloped i
a plan of action to shutdown the plant, repair the area; of concern and concuct a pneumatic test of the torus prior to returning to power.
During the October 1979 refueling outage the following wc,rk was performed' l
in conjunction with the LTP:
20 depressions resulting from indications in the torus wall that had been ground out were repaired.
r i
6c weld retal pads were welced to the torus shell.
44 gussets were welced tc the pacs.
8 During the 1980 fall refueling outage the following work was accomplished
[
as part of the " Mark I owners group LTP":
_._,r,.
Acdition of support saccles under the torus at each ring gircer.
Saddies were selded to the torus shell and anchored to the casemat.
i Sadcles are requitec in order to stiffen the torus shell assemoly and reduce its response to dynamic concensation loads.
The saddles j
l also transmit torus uplift loads (produced by pool swell) to the basemat.
Replacement of safety relief valve ramsheads with T-Quenchers and addition of T-Ouencher supports.
The T-Quencher is a perforated pipe connected to the end of the safety valve discharge torus cay j
and welced to two adjacent ring giroers.
1
Director's Decision 25
~
4 Installation of Vent Heacer Deflectors and Supports located below t
the vent neacer.
They are cesignec to recuce the load on the vent t
header produced by pool swell uplift.
Installation of Downtomer Ties.
Sections of pipe connected to clamps at either end were welded to the downcomers.
This' design prevents the downcomers from deflecting radially.
t 4
Modification of RHE Return Line Eeroute and Support in Torus.
This modification results in the piping running closer to the ring gircer f
where it is supported.
An elbow was added to promote better thermal mixing cf the RHR return water with the pool.
Replacement of 2" Safety Relief Valve Discharg_e.Li.e (SRVDL) Vacuum n
Breakers witn 10" vacuum creakers.
Tnese. allow equal _izing of :ne l
SRVDL-Drywell pressure without the occurrence of a high water leg it.
the line.
1 Replacement of wetwell-drywell vacuum breaker cast aluminum dist
{
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assemoly with a wrought aluminum disc assembly. This mitigates l
damage to the disc during the chugging phase of a steam blowcown.
[
i Reinforcement of 4" torus spray heacer support.
A plate was welded to the existing support to reduce the displacement of the J
pipe causeo by cool swell uplift loads.
i
Director's Decision 26 e
Modifications to Submerged Piping (HPCI and RCIC concensate returns, RCIC Turbine Exhaust) to reduce impact and drag loads.
+
Modification to torus catwalk to f acilitate removal durir.g power cperations.
The ateve modifications have been periodically monitored by the NRC Resident and Region based inspectors.
The licensee has completed the LTP modifications that should restore the original Torus safety-to-f ailure f actor. The licensee nas committet to succit a plant specific analysis according to criteria proviced in NUREG-0551.
This analysis will either confirm inat the cesign, with LTP mocifications in place, has the intended f
cargins of safety, or it wil-1 icentify any additional plant mccifications that are necessary to restore intended margins-of safety in the' containment design.
It is re-empnasizec that at no time did the NRC authorize Vermont Yankee coeration without the full tenefit of the Mark I containment e
system.
In summary, I find that the continuin; NRC and industry review and analysis of the various safety features of power reactors disclosed that certain design criteria for the BWR Mark I containment system did not contain the degree of conservatism originally expected.
I further find that GE, the containmen system oesigner, anc ne NRC licensees with Marn I containment
{
systems, working'together have developed on a generic basis corrective
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r L
i y
-4.
Director's Decision 27 e
actions which, wnen implemented, will restore tne degree of conservatism originally expectec.
Vermont Yankee has curing tne recent plant outage completed those corrections applicable to its f acility.
Further, I find i
tnat the licensee is committed to submit, on a timely basis, a plant specific analysis which will confirm the adequacy of modifications made -
to date, or describe such supplementary modifications as may be required.
Therefore, I find that there is no, basis for concucting an extensive public investigation and hearing on the sebject of containment system integrity.
5.
Inerting of Containment.
Ms. Callan and Mr. Richardson also allege that vermont Yankee is -the only f acility in the country that.coes not have an installed inerting system.
Ms Callan anc Mr. Richardson contene tna: "tnis safety unit wouic forestall a hycrogen explosion that woulc breach the reactor containment in the event of an accicent."
Inerting is not required for the Vermont Yankee plant by a ruling of the I
Appeal Board [ ALAS-229, September 18, 1974; 8 AEC 425, 428 (1974)).
On October 2,1980, the Commission published in tne Federal Register a j
proposed rule entitled " Interim Recuirements Relatec to Hycrogen Control and Certain Degraded Core Considerations" (45 FR 65466).
This rule would i
J 1
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Director's Decision 28
.w recuire the Vermont Yankee plant to inert sometime after rulemaking is i
completed.
The inerting woulc be required as an interim measure while I
long term rulemaking on degraded or melted cores proceeds.
The proposed i
tule states that:
"While the decrease in residual risk due to inerting these containments r
i is small, as determined by probabilistic analyses, (a) there are no i
significant countervailing safety disincentives; (b) the cost of inerting r
is small; and (c) there has been substantial satisfactory experience with inerting Mark 2 containments."
4 Recuiring Verment hankee to inert immediately would be very costly because it would substantially extend the present cutage i_n order.to aco equipment not included in the present design.
Inerefore the proposdd rule' does not call for immediate inerting.
1
'i The NRC regards the operation of the Vermont Yankee plant.with deinerted containment as acceptable pending comoletion of the rulemaking process.
t Consecuently, an investigation into the inerting issue is not warranted and no basis exists that would require preventing the. Vermont Yankee facility from resuming power operation.
II i
i Easeo on the foregoing, I have determinec that conduct of the requested additional investigation at Vermont Yankee is net warranted and'would not 9
l Director's Decision 29 serve to ennance safety based on the high level of NRC inspection effort that has already been expendec over several years on the issues raised by Ms. Callan f
and Mr. Richardson.
In addition, because there were no unexpected problems j
icentified during the current outage at Vermont Yankee, because the licensee was responsibly addressing previously identified NRC concerns, because the licensee's corrective action toward resolution of these concerns is acceptable j
to the NRC, and because there is reasonable assurance that Vermont Yankee can continue to operate without undue risk to the public health and safety, I have.
cetermined tnat no basis exists that woulc rouire the facility to remain i
snutoown.
Consequently, I nave denie: Ms. Callan and Mr. Richardson's requests for a full and public investigation into the safe operation of the Vermont Yankee facility anc for continvec shutcosn of the f acility until the investiga-i tion is complete.
Ms. Callan and Mr. Richaroson nave also recuested a hearing on the fincings of 1
an investigation into tne issues they nave aisec.
Uncer IC CFR 2.206, Ms.
Callan anc Mr. Richarcson are not entitlec to a hearing as a matter of right.
I woulc view their request for a hearinc as one tnet asks the Commission to i
l exercise its authority to grant a discretionary hearing.
Because I have l
denied Ms. Callan and Mr. Richardson's request for an investigation into the l
issues they raise, I would not recommend that the Commission grant a discre-tionary hearing to Ms. Callan and Mr. Richardson.
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' Director's Decision
~30 6
A' copy of this decision will be placed in the Commission's Public Document Room at 1717 H 5treet N.W., Washington, D.C. 20555 and in the local-puolic cocument room at Brooks Memorial Library, 224 Main Street, Brattleboro, Vermont,
-05321.
Additionally, a copy of this decision kill be filed 'with the Secretary of
- the Commission for review by the Commission in accordance with 10 CFR j
5ection 2.206(c) of the Commission's regulations.
As provided in'10 CFR 2,206(c), this decision will constitute finai action of the Commission twenty-five (25) days afte-the date e' issuance, unless the Commission on its own motion institutes the review of this decision within that time.
{
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r R. C. DeYoung Acting Directo,'
r Offi:e of Inspection anc Enforcement Dated at Bethesda, Maryland this r'
cay of
!.- _..'~.
, 1980
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