ACRS CRS MEE MEETING TING WITH WITH THE THE U.S. .S. NUCLE - - PowerPoint PPT Presentation

ACRS CRS MEE MEETING TING WITH WITH THE THE U.S. .S. NUCLE NUCLEAR AR REGU REGULA LATOR ORY Y COMM COMMISSION ISSION

March 5, 2015

Ov Over erview view

John W. Stetkar

2

• Since our last meeting with the

Commission on October 2, 2014, we issued 8 Reports

• Topics:

– Watts Bar Unit 2 Operating License – Draft Branch Technical Position 8-9 on Open Phase Conditions in Electric Power Systems – Assessment of the Quality of Selected NRC Research Projects – FY 2014

Accomplishments

3 3

• Topics (cont.):

– Report on the Safety Aspects of the Nuclear Innovation North America, LLC Combined License Application for South Texas Project Nuclear Station, Units 3 and 4 – Report of the Safety Aspects of the License Renewal Application of the Callaway Plant, Unit 1

4 4

• Topics (cont.):

– Commission Paper, “Integration of Mitigating Strategies for Beyond- Design-Basis External Events and the Reevaluation of Flooding Hazards” – Standard Review Plan Chapter 19 and Section 17.4 – Draft Generic Letter 20XX-XX, “Treatment of Natural Phenomena Hazards in Fuel Cycle Facilities”

5 5

Ongoing / Future Reviews

• New Plants

– Design Certification Application for US EPR – Reference COLA for US EPR (Calvert Cliffs) – Subsequent COLAs for AP1000 (Levy) and ESBWR (North Anna)

6 6

Ongoing / Future Reviews

• PSEG Early Site Permit
• Small Modular Reactors (NuScale)
• SHINE Medical Radioisotope

Production Facility

• License Renewal

– Sequoyah – Byron/Braidwood – Seabrook – Davis-Besse – Indian Point

7 7

Ongoing / Future Reviews

• Technical Issues for Subsequent

License Renewal

– Concrete Structures – Reactor Vessel and Internals – Electrical Cables – Others as Identified

• Risk-Informed Resolution of GSI-191,

“Ex Experimenta perimental l Stu Studies of dies of Los Loss-of

• f-

Coolant Coolant-Accident Accident-Gener Generated De ted Debris bris Accumula Accumulation and tion and Head Loss wit Head Loss with h Emp Emphas hasis is on the E

• n the Effects

ects of

• f Calcium

Calcium Silicate Insulation”

8 8

Ongoing / Future Reviews

• Fukushima Proposed Rulemaking

– Mitigation Strategies for Beyond- Design-Basis External Events – Interim Staff Guidance in Support of Order EA-13-109 (Reliable Hardened Vents) Phase 2 – Containment Protection and Release Reduction for BWRs with Mark I and Mark II Containments

9 9

Ongoing / Future Reviews

• Grand Gulf MELLLA+
• Nine Mile Point Unit 2 MELLLA+
• Topical Report NEDE-33766P

, “GEH Simplified Stability Solution (GS3)”

• Westinghouse Realistic Full

Spectrum LOCA Methodology

10 10

Ongoing / Future Reviews

• Risk Prioritization Initiative /

Cumulative Effects of Regulation

• Risk Management Regulatory

Framework

• Updated Regulatory Analysis

Guidance

• Level 3 PRA
• Human Reliability Analysis Methods

11 11

Review view of

• f TV

TVA A Oper Operating ting License A License Applica pplication tion for

• r Watts

tts Bar Nuc Bar Nuclear lear Plan Plant, t, Unit Unit 2

Harold B. Ray

12

• Watt

tts s Bar Bar Unit Unit 2 (WBN 2 (WBN 2) i 2) is s th the e se seco cond nd un unit it of

• f a

a du dual al-un unit it plan plant

• Par

art t 50 50 co cons nstr truc uctio tion n pe permit mit for

• r bo

both th un units its issu issued ed in in 1973 1973

• Watt

tts s Bar Bar Unit Unit 1 (WBN 1 (WBN 1) be 1) bega gan n

• p
• per

eration tion in in 1996 1996

• Co

Cons nstr truc uctio tion n of

• f W

WBN BN 2 w 2 was as su susp spen ende ded d 1985 1985 – 2006 2006

• SRM

SRM in 200 in 2007 7 af affi firmed med tha that t th the e li lice cens nsing ing ba basis sis for

• r WBN

WBN 2 w 2 wou

• uld

ld be be th the e sa same me as as WBN WBN 1, 1, co cons nsiste istent nt with pr with prior ior du dual al-un unit it plan plants ts

Background

13

Background (cont.)

• TV

TVA sub A submitted the op mitted the oper erating license ting license applica pplication f tion for WB

• r WBN 2 in

N 2 in 2009 2009

• ACR

CRS S has has held held 10 10 sub subcommittee committee meetings meetings betw between een Mar March 2009 h 2009 and and Januar anuary y 2015 2015

• An inte

An interim lette rim letter w r was as issued issued in in No November ember 2013 2013

• The

he interim interim letter letter listed spec listed specifi ific c issues issues f for fur

• r further

ther ACR CRS S review view

14

Final letter Final letter in in Febr bruar uary y 201 2015 5 reflected eflected

• ur comp
• ur completed

leted review view inc including luding:

• Gen

Generic eric Letter Letter (GL) (GL) 200 2004-02, “Potential Im Impact pact of

• f De

Debris bris Bloc Blocka kage ge on

• n Emer

Emergenc gency y Recir ecircula culation tion during during Des Design ign Bas Basis is Acc Accidents idents at t Pr Pres essu suriz rized ed-Water ter Reactors”

• GSI

GSI-191 191 issues issues, , inc including luding in in-vess essel el ef effects ects, r , res esolv

• lved

ed bas based ed on lo

• n low

w la latent tent de debris bris le levels els

15

Final l Final letter in etter in Febr bruar uary y 2015 2015 reflected eflected

• ur com
• ur completed r

pleted review view inc including luding: : (co

(cont.) nt.)

• Compliance

Compliance with Gener with General al Design Design Cri Criter terion ion 5 5 concer concerning shar ning shared ed systems systems

• Cyber

Cyber secu security rity desig design n and and confir confirma mator tory y testing testing

16

Febr bruar uary y 2015 2015 ACR CRS S letter r letter reflected eflected fur further ther review view of

• f spe

specific issues cific issues

(cont (cont.) .):

• Calcula

Calculation tion of

• f cor

core fuel e fuel temper temperatur ture

• Site

Site licensing licensing basis basis hy hydr drolog

• logy
• Fir

Fire e pr protection r

• tection rela

elated to ted to

• per
• perator

tor manual manual actions actions

• Oper

Operational r tional readiness eadiness pr prepar eparations tions

17

Our conc Our conclusion lusion:

• Ther

here e is is reaso easona nable ble assu assurance ance tha that t WBN WBN 2 2 can oper can operate te as as the the seco second nd unit unit of

• f th

the e dual dual unit unit Watts tts Bar Bar Nuc Nuclear lear Plant Plant wi withou thout t undu undue e risk risk to to the health the health and saf and safety ety of

• f the

the pub publi lic c

• The

he oper

• perating

ting li licens cense e for WBN

• r WBN 2

2 shou should ld be a be appr pproved ed foll

• llowi

wing ng completion completion of

• f r

remaini emaining ng staf staff inspections inspections and and closur losure e of

• f

remaini emaining ng open

• pen items

items

18

• The

he revise vised d Watt tts s Ba Bar r site site licen licensing sing ba basis sis reflect eflects s a a de dete terministica ministicall lly y es esta tablishe blished d Pr Prob

• bable

ble Max Maximum imum Flood lood, , co cons nsiste istent nt with cu with curren ent t pr prac actice tice

• We

e disc discus usse sed d with NR with NRC C st staf aff t the he de develo elopm pmen ent t of

• f a

a Pr Prob

• babilistic

bilistic Flood looding ing Hazar Hazard d Ana Analys ysis is met metho hodo dolog logy y for

• r f

fut utur ure us e use

• Sta

Staff has has a 5 a 5-yea ear r res esea earch h plan plan; ; we su e supp ppor

• rt

t th this is ef effor

• rt an

t and d welco elcome me en enga gage gemen ment t with th with the e st staf aff

19

Assessment of the Quality of NRC Research Projects

Michael L. Corradini

Bac Backgro kground und

• Throughout its history, an essential

activity of the ACRS has been reviewing the research sponsored by the NRC. Currently, such review includes:

– Review of research conducted in support

• f specific regulatory activities

– Episodic review of particularly important

• ngoing research

– Biennial review of the overall reactor safety research program – Research Quality Reviews

21

Motiv Motivation ation for Quality for Quality Rev Review iew

22

• Independent evaluation of the

quality and utility of research programs

• GPRA requirement
• ACRS agreed to undertake this task

in partial fulfillment of the Commission direction for ACRS to assume role previously performed by NSRRC

Quality Review P Quality Review Process rocess

• Review criteria originally developed

by ACRS & RES

• ACRS typically selects two or three

Projects from a list proposed by RES

• A panel of three ACRS members

assigned to each project to do an in- depth review

23

Quality Review P Quality Review Process (cont rocess (cont.) .)

• Meet with RES and sponsoring

program offices to better understand project scope and user need

• ACR

ACRS S th thre ree-memb member er pa pane nel l presents presents

• r
• ral

al an and d writt written en rep repor

• rt

t to to ent entire ire co committ mmittee ee for for pe peer er re review view

• Qua

Quali lity ty ra rating ting is is fi fina nali lized zed by by who whole le co committe mmittee

• Ann

Annua ual l re repo port rt to to RES RES dire direct ctor

• r

24

Evaluation Crit Evaluation Criteria eria and Weights and Weights

The Value Tree for Finished Projects

Research Quality Research Quality Success Documentation Results Meet the Objectives

Clarity of Presentation Identification

• f Major

Assumptions Soundness of Technical Approach/Results Uncertainties/ Sensitivities Addressed Justification Of Major Assumptions

0.16 0.09 0.12 0.52 0.11 0.25 0.75

Quality Review I Quality Review Issues ssues

• Are research objectives adequately

defined?

• Has an adequate technical approach

been pursued?

• Do results satisfy regulatory
• bjectives?
• Are uncertainties characterized?
• Is documentation adequate?

26

Scoring System Scoring System

27

Resear Research ch Quality Reviews Quality Reviews Completed Completed in FY 2014 in FY 2014

• NUREG/CR-7143: Characterization of

Thermal-Hydraulic and Ignition Phenomena in Prototypic, Full-Length Boiling Water Reactor Spent Fuel Pool Assemblies After a Postulated Complete Loss-of-Coolant Accident

• NUREG/CR-7148: Confirmatory Battery

Testing: The Use of Float Current Monitoring to Determine Battery State-

• f-Charge

28

Biennial Biennial Review Review of Resea

• f Research

rch Program Program

• ACR

ACRS S wil will l so soon

• n initiate

initiate its its bien biennial nial re review view of NRC

• f NRC Safet

Safety y Res Resea earc rch h Pr Prog

• gra

ram

• Considers the programmatic

justification for the research as well as the technical approaches and progress of the work

• Identifies research crucial to the

NRC missions

• Will report to Commission in March

2016 and the final report will be issued as NUREG-1635, Vol. 12

29

Biennial Biennial Review Review of Resea

• f Research

rch Program Program

• General Observations and Recommendations
• Special Topic of Current Interest
• Advanced Reactor Designs
• Digital Instrumentation and Control Systems
• Fire Safety
• Reactor Fuel
• Human Factors and Human Reliability
• Materials and Metallurgy
• Neutronics and Criticality Safety
• Operational Experience
• Probabilistic Risk Assessment
• Radiation Protection
• Nuclear Materials and Waste
• Seismic and Structural Engineering
• Severe Accidents and Source Term
• Thermal Hydraulics

30

Draft Draft Branch Tech Branch Technical nical Pos Position ition 8-9 on Open 9 on Open Phas Phase e Conditions (OPC) Conditions (OPC) in in Elec Electric Power tric Power Sy Systems stems

Dennis Bley

What Is What Is An An Open Open Phase Conditi Phase Condition?

• n?

32

33

By Byron Station OPC ron Station OPC 2012 2012

• Operators notice pumps tripping
• RCP trip caused reactor trip
• Concealed cause – not diagnosed

for 8 minutes

• Loss of RCP seal cooling for

8 minutes

• Unbalanced three-phase currents

can damage plant equipment

Informat Information Not ion Notice & Bu ice & Bulletin lletin

• Information Notice 2012-03 and

Bulletin 2012-01, “Design Vulnerability in Electric Power System”

• To gather information from

licensees on the potential design vulnerability and to determine whether additional actions are needed

34

OPC Even OPC Events Do Hap ts Do Happen pen

• Eleven OPCs at ten operating

plants in fourteen years

• OPC can be difficult to detect, and

can damage equipment

• Some of these events went

undetected for several weeks

35

BTP 8 BTP 8-9 Re 9 Require quires

• Detection of single- and double-

phase faults

• Alarms to alert the operators
• Actuation circuits to separate the

faulted source from the plant and to transfer safety-related loads to an alternative source

• Draft was further clarified in a staff

letter to NEI dated Nov. 25, 2014

36

Also: Also:

• Draft BTP requirements clearly

defined and well supported

• Automatic actuation required only

when OPC signal coincident with a plant accident signal

37

ACR ACRS S Recommendation Recommendation

• BTP 8-9 should require similar

protection for onsite power connections to the high voltage side of a plant transformer, unless the circuit is fully contained in an isolated-phase bus

• Staff agreed

38

Indust Industry Initiative ry Initiatives

• EPRI, licensees, and vendors have

developed methods for detecting a wide variety of fault conditions

• Licensees are developing

procedures to assist operators in identifying and isolating faults

• NEI reported that their guidance

specifies actuation on the open phase signal alone, if a transformer supplies more than one safety bus

39

Abbre Abbreviations viations

ABWR Advanced Boiling Water Reactor AC alternating current ACRS Advisory Committee on Reactor Safeguards APWR Advanced Pressurized Water Reactor AP1000 Advanced Passive 1000 BWR Boiling Water Reactor BTP Branch Technical Position COLA Combined License Application CPRR Containment Protection and Release Reduction EA enforcement action EPR Evolutionary Power Reactor ESBWR Economic Simplified Boiling Water Reactor EPRI Electric Power Research Institute FY Fiscal Year GEH General Electric Hitachi GL generic letter GSI Generic Safety Issue GPRA Government Performance and Results Acts of 1994 LOCA loss-of-coolant accident MELLLA+ Maximum Extended Load Line Limit Analysis NEI Nuclear Energy Institute NRC Nuclear Regulatory Commission NSRRC Nuclear Safety Research Review Committee NUREG/CR NRC technical report designation/ contractor report OL

• perating license

OPC

• pen phase conditions

PRA Probabilistic Risk Assessment PSEG Public Service Electric & Gas Company RCP reactant coolant pump RES Office on Nuclear Reactor Research SER Safety Evaluation Report SHINE SHINE Medical Technologies, Inc. SRM staff requirements memorandum/memoranda TVA Tennessee Valley Authority US United States

40