POLICY ISSUE

(Notation Vote)

July 15, 2005 SECY-05-0126

FOR: The Commissioners

FROM: Luis A. Reyes

Executive Director for Operations /RA/

SUBJECT: SUMMARY OF ACTIVITIES RELATED TO GENERIC SAFETY ISSUES

(WITS198300621)

PURPOSE:

To present the annual summary of activities related to generic safety issues (GSIs), and to

recommend discontinuing future annual summaries.

BACKGROUND:

Since 1983, the staff of the U.S. Nuclear Regulatory Commission (NRC) has adhered to the

practice of providing the Commission with an annual update of the progress made in resolving

GSIs. The Commission reinforced this practice in a staff requirements memorandum (SRM)

dated May 8, 1998, in response to SECY-98-030, “Implementation of [Direction-Setting Issue]

DSI-22 Research,” in which the Commission directed the staff to provide an annual summary of

activities related to open reactor and non-reactor GSIs.

Management Directive (MD) 6.4, “Generic Issues Program,” dated December 2001, delineates

the NRC’s program for addressing reactor and non-reactor generic issues (GIs). Specifically,

the program described in MD 6.4 comprises seven stages, including (1) identification,

(2) initial screening, (3) technical assessment, (4) regulation and guidance development, 

(5) regulation and guidance issuance, (6) implementation, and (7) verification. Candidate

generic issues may be identified by organizations or individuals either within or external to the

NRC.

CONTACT: Ronald C. Emrit, RES

(301) 415-6447
The Commissioners -2-

Generally, safety concerns associated with operating events, research results, or risk

assessments form the basis for the identification of GIs by the NRC staff, the Advisory

Committee on Reactor Safeguards (ACRS), the nuclear industry, or the public. After an issue

is identified, the staff conducts an initial screening exercise to determine whether it should be

processed as a GSI, excluded from further analysis, or sent to another NRC program for

review. In the technical assessment stage, the staff determines whether the issue involves

adequate protection, safety enhancement, or burden reduction. In addition, the staff’s related

technical findings become the basis for developing or revising agency rules, guidance, and

programs. In the final three stages, the agency issues new or revised regulations or guidance,

which are then implemented by licensees and/or certificate holders, and verified by the NRC. 

GIs identified after March 1999 have been processed in accordance with MD 6.4. In addition,

all open GSIs are periodically reviewed in accordance with the MD 6.4 criteria for possible

designation as unresolved safety issues (USIs), and the management directive contains

additional Congressional reporting requirements for the subset of GSIs that meet those USI

criteria.

The NRC’s Office of Nuclear Regulatory Research (RES) tracks the status of all GSIs in the

agencywide Generic Issue Management Control System (GIMCS) and documents the initial

screening analyses and disposition of all issues in NUREG-0933, “A Prioritization of Generic

Safety Issues.”

DISCUSSION:

Since the staff issued its previous report to the Commission (SECY-04-0156) on August 27,

2004, two new GIs have been identified (GIs 198 and 199), and one has been screened and

added to the list of GSIs that require technical assessment (GI 196). As a result, 16 GSIs

remain to be resolved as the staff continues to follow the MD 6.4 process of identifying and

resolving reactor and non-reactor GSIs.

Reactor GSIs

The RES staff is responsible for screening all new GIs associated with nuclear reactor power

plants, and performing the technical assessments of those GSIs that the screening identifies as

warranting further processing. The Office of Nuclear Reactor Regulation (NRR) is responsible

for developing and issuing regulations or guidance that may be recommended in the technical

assessments, and subsequently verifies the implementation of the resultant regulation or

guidance by licensees and/or certificate holders. The staff also conducts an “adequate

protection evaluation” for each newly identified GSI to determine whether plants should

continue operating while the issue is being resolved.

Over the past several years, the number of new GIs identified has decreased to an average of

approximately two per year, and the staff has closed 836 of the 849 reactor generic issues

identified since the inception of the generic issues program in 1976. The attachment to this

paper describes the 13 reactor GIs that remain open at this time and summarizes the status of

their initial screening, technical assessment, and regulation and guidance development. The

following subsections summarize the activities related to reactor GIs since the staff issued its

previous report to the Commission on August 27, 2004.
The Commissioners -3-

Identification

The staff identified two new GIs for initial screening:

198 Hydrogen Combustion in PWR Piping

199 Implications of Updated Probabilistic Seismic Hazard Estimates in Central and

Eastern United States

Initial Screening

The staff completed the initial screening of the following GI:

196 Boral Degradation

The staff began the initial screening of the following GI:

197 Iodine Spiking Phenomena

Technical Assessment

The following seven GSIs are undergoing technical assessment:

80 Pipe Break Effects on Control Rod Drive (CRD) Hydraulic Lines in the

Drywells of BWR MARK I and II Containments

156.6.1 Pipe Break Effects on Systems and Components

163 Multiple Steam Generator Tube Leakage

185 Control of Recriticality Following Small-Break LOCAs in Pressurized-Water

Reactors (PWRs)

188 Steam Generator Tube Leaks/Ruptures Concurrent with Containment

Bypass

193 Boiling-Water Reactor (BWR) Emergency Core Cooling System (ECCS)

Suction Concerns

196 Boral Degradation

Regulation and Guidance Development

Regulation and guidance development continued on the following three GSIs:

186 Potential Risk and Consequences of Heavy Load Drops

189 Susceptibility of Ice Condenser and MARK III Containments to Early Failure

from Hydrogen Combustion During a Severe Accident

191 Assessment of Debris Accumulation on PWR Sump Performance

Non-Reactor GSIs

The NRC’s Office of Nuclear Material Safety and Safeguards (NMSS) has primary responsibility

for processing non-reactor GSIs through all stages of MD 6.4, and RES tracks the status of

unresolved non-reactor GSIs in the quarterly updates of GIMCS. The attachment to this paper
The Commissioners -4-

describes the three non-reactor GSIs that remain open at this time, and summarizes the status

of their technical assessment or regulation and guidance development. The following

subsections summarize the activities related to non-reactor GSIs since the staff issued its

previous report to the Commission on August 27, 2004.

Identification

The staff did not identify any new GI for screening.

Initial Screening

No initial screening activities were warranted during this reporting period.

Technical Assessment

The following two GSIs are undergoing technical assessment:

NMSS-7 Criticality Benchmarks Greater than 5% Enrichment

NMSS-14 Surety Estimates for Groundwater Restoration at In Situ Leach Facilities

Regulation and Guidance Development

Regulation and guidance development continued on the following GSI:

NMSS-16 Adequacy of 0.05 Weight Percent Limit in 10 CFR Part 40

Reporting

The following reports provide information on the staff’s progress in resolving GSIs:

(1) Monthly: RES provides input to Section III, “Status of Issues in the Reactor

Generic Issue Program,” of the monthly status report to the U.S. Senate

Committee on Environment and Public Works, on the NRC’s licensing activities

and regulatory duties. The RES input focuses on significant accomplishments in

resolving open reactor GSIs during each calendar month.

(2) Quarterly: In addition to the RES quarterly GIMCS report mentioned above,

NRR publishes the Director’s Status Report on Generic Activities which includes

the status of reactor GSIs that are undergoing regulation and guidance

development.

(3) Annually: A report on the resolution status of selected reactor GSIs is included

in NUREG-1542, “U.S. Nuclear Regulatory Commission Performance and

Accountability Report,” which is published annually. In addition, the NRC

publishes annual supplements to NUREG-0933 to document the initial screening

analyses and the disposition of GSIs that were closed during the reporting period

(July 1 to June 30).
The Commissioners -5-

In addition, the operating plans of the responsible offices track the schedule for the completion

of each GSI.

In its continuing effort to improve the efficiency of its activities, the staff has noted some

redundancy in its reporting of GSI information. Specifically, this annual report to the

Commission duplicates the information that the staff provides in its quarterly GIMCS and NRR

Director’s reports. Similarly, the information on significant accomplishments, initial screening

results, and the final disposition of GSIs in this report is also provided to the Commission in the

monthly report to the U.S. Senate Committee on Environment and Public Works, the annual

Performance and Accountability Report (NUREG-1542), and NUREG-0933, as described

above.

RECOMMENDATION:

The staff currently produces several periodic reports that document progress in resolving GSIs. 

However, the staff recommends that the Commission discontinue this annual report in order to

eliminate the redundancy that presently exists in the various reports. The staff will continue to

use the aforementioned reporting mechanisms to meet the intent of DSI-22 and provide

updates to the Commission on activities related to all open GSIs.

/RA/

Luis A. Reyes

Executive Director

 for Operations

Attachment: Description and Status of Open

GSIs as of July 5, 2005
The Commissioners -5-

In addition, the operating plans of the responsible offices track the schedule for the completion

of each GSI.

In its continuing effort to improve the efficiency of its activities, the staff has noted some

redundancy in its reporting of GSI information. Specifically, this annual report to the

Commission duplicates the information that the staff provides in its quarterly GIMCS and NRR

Director’s reports. Similarly, the information on significant accomplishments, initial screening

results, and the final disposition of GSIs in this report is also provided to the Commission in the

monthly report to the U.S. Senate Committee on Environment and Public Works, the annual

Performance and Accountability Report (NUREG-1542), and NUREG-0933, as described

above.

RECOMMENDATION:

The staff currently produces several periodic reports that document progress in resolving GSIs. 

However, the staff recommends that the Commission discontinue this annual report in order to

eliminate the redundancy that presently exists in the various reports. The staff will continue to

use the aforementioned reporting mechanisms to meet the intent of DSI-22 and provide

updates to the Commission on activities related to all open GSIs.

/RA/

Luis A. Reyes

Executive Director

 for Operations

Attachment: Description and Status of Open

GSIs as of July 5, 2005

(WITS# 198300621)

E:\Filenet\ML051790296.wpd

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OFFICE *RES E *RES E *RES E *RES E *RES E *TECH

EDITOR

E

NAME REmrit:dfw HVandermolen JIbarra FBrown FEltawila PGarrity(Electronic)

DATE 06/08/05 06/08/05 06/08/05 06/15/05 06/28/05 07/05/05

OFFICE *D:NMSS E *D:NRR E *D:RES E DEDMRS E EDO E *SISP

REVIEW

NAME JStrosnider JDyer CPaperiello MVirgilio LReyes REmrit

DATE 06/20/05 06/27/05* 07/07/05 07/15/05 07/15/05 07/06/05

OFFICE *SISP

REVIEW

E

NAME JIbarra

DATE 07/06/05
Description and Status of Open GSIs as of June 8, 2005

GSI

Number

Title Lead

Office

Description St

80 Pipe Break Effects on Control

Rod Drive Hydraulic Lines in theDrywells of BWR MARK I and IIContainments

RES This issue involves a concern about the

likelihood and effects of a LOCA, whichcould cause interactions with the CRDhydraulic lines and prevent rod insertion,and create the potential for recriticalitywhen the reactor core is reflooded.

The staff completed a teffects of postulated pipMark I and Mark II contelement code was used transient analysis to depipe break impulsive loThe analysis indicated twill not be impacted by steam, and feedwater spostulated break. The document its technical planning to brief the ACSeptember 2005. The completion in Decembe

156.6.1 Pipe Break Effects on Systems

and Components

RES This issue involves a safety concern about

whether the designs of some plantsadequately address the effects of pipebreaks inside containments.

A finite element code wimpact of impulsive loadfeedwater, main steamsystem piping on the dranalysis indicated that tand leak-tightness of dnot be compromised by staff plans to validate its the piping configurationmaking any recommenscheduled for completio
Description and Status of Open GSIs as of June 8, 2005

GSI

Number

Title Lead

Office

Description St

-2-

163 Multiple Steam Generator Tube

Leakage

NRR This issue addresses a safety concern

about multiple steam generator tube leaksduring a main steam line break that cannotbe isolated.

Resolving this issue is aNRC’s Steam Generato3.1, 3.7, 3.8, and 3.9). a more technically robutreatment of radionuclidthe safety analyses of dThe technical assessmscheduled for completio2005.

185 Control of Recriticality Following

Small-Break LOCA in PWRs

RES This issue addresses small-break LOCA

scenarios in PWRs that involve steamgeneration in the core and condensation in thesteam generators, which may causedeborated water to accumulate in part ofthe reactor coolant system (RCS). In suchscenarios, restarting the RCS circulationmay cause a recriticality event (reactivityexcursion) by moving the deborated waterinto the core.

The study of "Boron DiSmall-Break LOCAs in with the conclusion tharecriticality for CE and Wbased on the relatively volumes. Recriticality is plants under certain cirexisting procedures shodamage. The staff findthe ACRS on October proceeding with closing imposition of any new rfor all Framatome B&WCombustion Engineerinscheduled to complete technical assessment oSeptember 2005.
Description and Status of Open GSIs as of June 8, 2005

GSI

Number

Title Lead

Office

Description St

-3-

186 Potential Risk and

Consequences of Heavy LoadDrops in Nuclear Power Plants

RES This issue resulted from a staff review of

licensees’ programs for handling heavyloads, which revealed that dropping a heavyload has a substantially greater potential forsevere consequences than the industrypreviously envisioned.

The staff is currently deIssue Summary to clariexisting regulatory guidheavy loads, and to endstandard, American SoEngineers (ASME) NOConstruction of Overheas an acceptable methoguidance. However, ththis endorsement from Committee has been dto brief the ACRS on thstaff’s recommendationissue is scheduled for c2006.

188 Steam Generator Tube

Leaks/Ruptures Concurrent WithContainment Bypass

RES This issue addresses the effects on the

validity of steam generator tube leak andrupture analyses of resonance vibrations insteam generator tubes during steam linebreak depressurization.

A draft study completed 2004 showed that the dassociated with an MSLthe integrity of the tubecircumferential cracking will be issued as a NURis scheduled to close th2005 without imposing requirements on license
Description and Status of Open GSIs as of June 8, 2005

GSI

Number

Title Lead

Office

Description St

-4-

189 Susceptibility of Ice Condenser

and MARK III Containments toEarly Failure From HydrogenCombustion During a SevereAccident

NRR NUREG/CR-6427, “Assessment of the

Direct Containment Heat (DCH) Issue forPlants with Ice Condenser Containments,”showed that the early containment failureprobability in ice condensers is dominated

by non-DCH hydrogen combustion events. The staff subsequently extended the issueto include BWR MARK III containmentsbecause their relatively low free volume andstrength are comparable to PWR icecondensers.

The staff concluded thaon providing backup poof hydrogen igniters is nice condenser or MARK pursuing rulemaking, thstakeholders on Septeminput on the draft desigpower supply for hydrocriteria were generally alicensees proposed volproviding backup poweissue letters to the affecinformation on their actvoluntary actions.In February and early Mmet with industry reprethis issue. On March 3with senior representatutilities to present additissue is scheduled to b2010.
Description and Status of Open GSIs as of June 8, 2005

GSI

Number

Title Lead

Office

Description St

-5-

191 Assessment of Debris

Accumulation on PWR SumpPerformance

NRR This issue concerns the possibility that

debris accumulating on the ECCS sumpscreen may result in a loss of the netpositive suction head (NPSH) margin. Lossof NPSH margin could impede or preventthe flow of water from the sump, which isnecessary to meet the criteria of 10 CFR50.46.

The staff issued GenerSeptember 13, 2004, roperating PWRs to perevaluations of the recirctheir emergency core cspray systems. In Octoreviewed the staff’s safemethodology proposed performing the plant-spIn January and April 20meetings with the Nucl(NEI) and owners to dis(2004-02 and the staff’and to address questioSE and NEI’s guidance to audit implementation initiated.

193 BWR ECCS Suction Concerns RES This issue involves a concern about the

possible failure of the ECCS caused byunanticipated, large quantities of entrainedgas in the suction piping from BWRsuppression pools. The issue applies toMARK I, II, and III containments duringlarge- and medium-break loss-of-coolantaccidents (LOCAs), and could potentiallylead to pump failure or degradedperformance as a result of gas binding,vapor locking, or cavitation. 

The staff completed a linformation on ECCS pduring high voiding inta2005. Efforts are undecontractor assistance to analyses for (1) gas ingto the downcomer blowdynamics, and (3) gas-perforated plate.
Description and Status of Open GSIs as of June 8, 2005

GSI

Number

Title Lead

Office

Description St

-6-

196 Boral Degradation RES This issue involves a concern about

degradation mechanisms that could impairthe effectiveness of Boral as a neutronabsorber in spent fuel casks.

The staff completed the issue was completed oand recommended conissue. A Task Action PAssessment of the issuFebruary 22, 2005. Effgather, review, and sumneeded to evaluate Borcasks and their potentiaestimated frequency of 

197 Iodine Spiking Phenomena RES This issue involves the ACRS concern

about the conservative, empirical treatmentof iodine spiking in accident consequenceanalyses. The ACRS recommended thatthe staff develop a mechanisticunderstanding of iodine spiking phenomenaso that analyses would reflect current plantoperations and the capabilities of modernfuel rods to prevent coolant contamination.

This issue was identifiestaff is scheduled to coscreening in June 2005

198 Hydrogen Combustion in PWR

Piping

RES This issue emerged in the analysis of GI195 when it was observed that numerous 

hydrogen detonation/explosion events hadalso been reported at PWR plants. 

The screening analysis scheduled for completio

199 Implications of Updated

Probabilistic Seismic HazardEstimates in Central andEastern United States

RES The issue involves the concern about the

higher seismic hazard at current nuclearpower plants in the Central and EasternUnited States according to the latest studiesconducted by the U.S. Geological Survey.

The staff is collecting ainformation on this issuscreening analysis.
Description and Status of Open GSIs as of June 8, 2005

GSI

Number

Title Lead

Office

Description St

-7-

NMSS-07 Criticality Benchmarks Greater

Than 5% Enrichment

NMSS This issue requires developing and

confirming the adequacy of methods,analytical tools, and guidance for criticalitysafety software for validating criticalitycalculations, including requests to processhigher enrichments, in the licensing ofnuclear facilities.

The staff is scheduled tthe end of June 2005 o

new methods for criticavalidating criticality calcscheduled for completio

NMSS-14 Surety Estimates for

Groundwater Restoration at InSitu Leach Facilities

NMSS This issue concerns the development of

methodologies to (1) calculate surety forgroundwater restoration activities at in situleach uranium extraction facilities and (2)monitor the post-restoration stability ofgroundwater quality.

The U.S. Geological Su2003 draft report “ConsGeochemical Issues in Restoration at Uranium Facilities” to incorporate provided by the industrreport to the NRC in Detechnical assessment ofor completion by July 2

NMSS-16 Adequacy of 0.05 Weight

Percent Limit in 10 CFR Part 40

NMSS This issue concerns the adequacy of

transferring source material containing lessthan 0.05 Wt% uranium or thorium inquantities that could result in annual dosesthat exceed NRC’s public dose limit of 100millirem/year from all sources.

On June 24, 2003, the Commission in SECY-0to postpone work on a Commission could reviethe staff regarding othecould impact the action The Commission respo2003 SRM by directing reviewing transfers of mthan 0.05 Wt% uranium previous Commission gRule has not restarted.