ML21133A266: Difference between revisions

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a      UNITEDSTATES National  institute DEPARTMENT ofStandards OFCOMMERCE andTechnology b4TIS 9/
OS Gaithersburg, Maryland  20899-May  13,2021 Document    Control  Desk U.S. Nuclear  Regulatory    Commission Washington,DC        20555-0001
 
==Subject:==
Follow-up    toevent  report Ref:  NRCEvent      Report  #55120,  Docket    50-184, Facility  License TR-5 Sirs andMadams:
OnMarch    5,2021,    the NCNR(NIST        Center  for Neutron  Research)submitted  a report of exceeding  a safety  limitonthe  event  ofFebruary 3, 2021 (original Event      Report #55094).
Inresponse    tothe  event, we instituted  aninvestigation into the    rootcauses  andhave uncovered    evidence  tosuggest  that there    wasanunlatched element inthe    core prior to reactor startup  onFebruary    3.Theinvestigation      hasidentified inadequacies inthe implementation    ofadministrative    andprocedural      controls.Specifically, these inadequacies  areasfollows:
1)t raining andproficiencies    infuel  latching,
: 2) procedures    infuel movements    andlatching,
: 3) enforcement    of procedural  compliance 4)implementation      oflatch  verification    methods,  and 5)management      oversight  of  refueling    staffing Accordingly,  we reported    this bytelephone      tothe NRCHeadquarters      Operation Center onMay6,2021        andaresubmitting      this  14-day  report inaccordance    withNBSR Technical  Specification    6.7.2(1)(g).
Inaddition,  inaccordance    with  reporting    requirements  inNBSRTechnical    Specification 6.7.2(1)(d)  we  have  i dentifiedthat the  i  ntentof the f ollowing Limiting  Conditions for Operation  wasnotmet:
* TS3.1.3      Thereactor  shall notoperate      unless all gridpositions  arefilledwith fuel length  fuel  elements  or thimbles,    except  during            and subcritical    critical startup testing  with  natural  convections    flow.
Eventhough      itwasbelieved    that  thisspecification  wasmetonFebruary    3,2021 priorreactor to          startup, subsequent    investigation  found that an  elementin position J-7  wasoutofthe      lower  grid  plate. Itisnow presumed    that  thiselement wasout ofposition    prior toreactor  startup.
e  TS3.9.2.1.      "Following  handling    offitelwithin  the reactorvessel, thereactor shall  notbeoperated    until all fuel  elements  that have been handled  areinspected
 
todetermine    that theyarelocked  intheir proper      inthe positions      grid core structure. This      beaccomplished shall              byoneof  following the      methods:
(1) Elevation check  ofthe  fuelelement with mainpumpflow.
(2) Rotational check  ofthe  elementhead inthelatching direction only.
(3)Visual inspection of    thefuelelement headorlatching "
bar.
After  therefueling onJanuary        the 4,2021,  required rotational checks were completedand signed off.      However,  investigation the                the following February 3
event  showedthat these checks  weredone incorrectly, andthusdid notmeetthe intent  ofTS3.9.2.1.
feel Please    free  tocontact meif  you haveanyquestions.
Respeclly    subitted,
                /
/'      .
Thomas Newton DeputyDirector    andChief ofReactor Operations andEngineering NISTCenter  for  Neutron Research}}

Revision as of 13:17, 8 September 2021

Us Dept. of Commerce, National Institute of Standards & Technology, Follow-Up to Event Report
ML21133A266
Person / Time
Site: National Bureau of Standards Reactor
Issue date: 05/13/2021
From: Newton T
US Dept of Commerce, National Institute of Standards & Technology (NIST)
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
55120
Download: ML21133A266 (2)
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