Information Notice 2005-08, Monitoring Vibration to Detect Circumferential Cracking of Reactor Coolant Pump and Reactor Recirculation Pump Shafts: Difference between revisions

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| issue date = 04/05/2005
| issue date = 04/05/2005
| title = Monitoring Vibration to Detect Circumferential Cracking of Reactor Coolant Pump and Reactor Recirculation Pump Shafts
| title = Monitoring Vibration to Detect Circumferential Cracking of Reactor Coolant Pump and Reactor Recirculation Pump Shafts
| author name = Hiland P L
| author name = Hiland P
| author affiliation = NRC/NRR/DIPM/IROB
| author affiliation = NRC/NRR/DIPM/IROB
| addressee name =  
| addressee name =  
Line 15: Line 15:
| page count = 5
| page count = 5
}}
}}
{{#Wiki_filter:UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR REACTOR REGULATIONWASHINGTON, D.C. 20555April 5, 2005NRC INFORMATION NOTICE 2005-08:MONITORING VIBRATION TO DETECTCIRCUMFERENTIAL CRACKING OF REACTORCOOLANT PUMP AND REACTORRECIRCULATION PUMP SHAFTS
{{#Wiki_filter:UNITED STATES
 
NUCLEAR REGULATORY COMMISSION
 
OFFICE OF NUCLEAR REACTOR REGULATION
 
WASHINGTON, D.C. 20555 April 5, 2005 NRC INFORMATION NOTICE 2005-08:                 MONITORING VIBRATION TO DETECT
 
CIRCUMFERENTIAL CRACKING OF REACTOR
 
COOLANT PUMP AND REACTOR
 
RECIRCULATION PUMP SHAFTS


==ADDRESSEES==
==ADDRESSEES==
All holders of operating licenses for nuclear power reactors, except those who havepermanently ceased operations and have certified that fuel has been permanently removedfrom the reactor vessel.
All holders of operating licenses for nuclear power reactors, except those who have
 
permanently ceased operations and have certified that fuel has been permanently removed
 
from the reactor vessel.


==PURPOSE==
==PURPOSE==
The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice (IN) to alertaddressees to the importance of timely detection of circumferential cracking of reactor coolantpump (RCP) and reactor recirculation pump (RRP) shafts to minimize the likelihood ofconsequential shaft failures. It is expected that recipients will review the information for applicability to their facilities andconsider actions, as appropriate, to avoid similar problems. However, the suggestions in this INare not NRC requirements; therefore, no specific action or written response is required.
The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice (IN) to alert
 
addressees to the importance of timely detection of circumferential cracking of reactor coolant
 
pump (RCP) and reactor recirculation pump (RRP) shafts to minimize the likelihood of
 
consequential shaft failures.
 
It is expected that recipients will review the information for applicability to their facilities and
 
consider actions, as appropriate, to avoid similar problems. However, the suggestions in this IN
 
are not NRC requirements; therefore, no specific action or written response is required.


==DESCRIPTION OF CIRCUMSTANCES==
==DESCRIPTION OF CIRCUMSTANCES==
General Electric (GE) Nuclear Services Information Letter (SIL) 459-S2, issued October 21,1991, informed GE boiling water reactor (BWR) owners of shaft cracking in RRPs. The rootcause was determined to be fatigue initiated by thermal stresses that, combined withmechanical stresses, caused cracks to propagate. GE recommended countermeasuresincluding shaft vibration monitoring, inspection of shafts with greater than 80,000 hours ofservice, and measures to reduce mechanical and thermal stresses.At Hope Creek, RRPs had accumulated over 130,000 hours of service without pump shaftinspections. The licensee had operated the B RRP for several refueling cycles with vibrationlevels approaching vendor limits. During this time, the licensee also identified failed anddegraded RRP seals and concluded that the most likely causes of the failed and degraded RRPseals were a possible bow in the pump shaft and low reliability of the seal purge system. The licensee's decision to restart following the fall 2004 refueling outage without correcting thiscondition led to heightened public interest and prompted a close NRC review. The staffevaluated site-specific technical details, related domestic and international operatingexperience, and the generic safety aspects of vibration-related shaft and seal failure. Circumferential cracking of RCP and RRP shafts had previously been reported at severalfacilities including Sequoyah, Palo Verde, St. Lucie, and Grand Gulf. In addition, reactorcoolant pump shafts at Crystal River separated completely during operation on two occasions(see IN 86-19 and IN 89-15).The staff evaluated the licensee's determination that the Hope Creek unit could be safelyreturned to power with the existing pump shaft and the interim compensatory measuresimplemented to provide reasonable assurance that a shaft failure could be detected in itsincipient stage and operators would take prompt action to prevent the occurrence of a potentialshaft and seal failure. The licensee committed to (1) replace the B pump shaft at the nextoutage of sufficient duration and to (2) establish a comprehensive program of enhancedcontinuous vibration monitoring to ensure timely detection of circumferential crack propagationwith proceduralized contingency actions for plant operators to act promptly at specifiedadministrative vibration limits to reduce pump speed or shut the pump down completely. Thesame monitoring regime was implemented for the A RRP.The Hope Creek licensee implemented a program to continuously monitor the synchronousspeed (1X) vibration amplitude, two times synchronous speed (2X) vibration amplitude, 1Xphase angle, and 2X phase angle. These parameters provide a more sensitive leadingindicator of circumferential crack initiation and propagation giving the operators enough time torespond. Alarm limits were established using the ASME OM standard, "Reactor Coolant andRecirculation Pump Condition Monitoring." GE SIL 459 indicates that all Byron Jackson (now Flowserve) RRP shafts inspected haveshown some degree of thermally induced cracking. The cracking occurs near the pumpthermal barrier where the cold seal purge system water mixes with the hot reactor coolantwater. The cracks initiate as axial cracks in the pump shaft. Axial cracks are generally benign,grow slowly, and do not affect the operation of the pump. However, given sufficient mechanicalloads, the axial cracks can change direction and propagate circumferentially. The time it takesto transition from slow-growing axial cracks to more rapidly growing circumferential cracksdepends on the magnitude of the mechanical loads on the pump shaft. It could take years. Onthe other hand, circumferential shaft cracking can propagate rapidly and, if not detected early,may result in complete severance of the shaft.Circumferential shaft cracking or shaft separation could result in pump damage anddegradation or failure of the pump seal package resulting in leakage of reactor coolant throughclearances around the upper portion of the pump shaft. However, at Crystal River - where theonly two instances of shaft failure occurred at domestic nuclear power plants - there was noevidence of seal degradation. A loss-of-coolant accident can occur if leakage through the sealsof a RRP or RCP exceeds the capacity of the normal makeup systems. Thus circumferentialshaft cracking that leads to shaft or seal failure is a safety concern. As noted above, vibration-monitoring systems are available to detect circumferential cracking ofpump shafts. As circumferential cracks propagate, the stiffness of the pump shaft changes. These changes are detectable through changes in the pump vibration signature prior to shaftfailure. Although overall pump vibration limits are necessary for assessing gaps and clearancesin the pump, they are not the most appropriate indicator of shaft cracking. Monitoring the 1Xand 2X steady-state vectors (1X and 2X amplitudes and phase angles) provides a betterindication of changes in shaft integrity resulting from circumferential crack propagation. Licensees should be alert to the possibility of circumferential RCP or RRP shaft cracking andshould evaluate the information in this IN and determine what actions, if any, are prudent toprovide early detection of circumferential shaft cracking and prevent failure of RRP or RCPshafts and shaft seals.GENERIC IMPLICATIONSA significant number (about half) of the BWR RRP pump shafts currently in service are olderand have more hours of operation than those at Hope Creek and many have not beeninspected as recommended in GE SIL 459-S2.About a half-dozen BWR RRPs were identified as having higher vibration levels than HopeCreek. Such issues would not necessarily be reported to the NRC. The staff contacted threeBWR licensees whose plants had been reported to have higher vibration levels than HopeCreek. The three plants included Susquehanna Units 1 and 2, Peach Bottom Units 2 and 3,and Browns Ferry Units 2 and 3. The staff discussed with each licensee how it monitors pumpvibration, the vibration acceptance criteria used, and why the current vibration levels areacceptable. These licensees indicated that they have either replaced their pump shafts (or willin the near future) or are taking steps to monitor RRP vibration and have establishedacceptance criteria to detect anomalous behavior.Operating experience suggests that pressurized water reactor (PWR) RCPs are not immune tovibration-related shaft and seal failure concerns similar to BWR RRP concerns. PWR RCP sealfailure can be more safety significant than BWR RRP seal failure because (1) PWR reactorcoolant systems operate at higher pressures, increasing the differential pressure across thepump seals and (2) PWR RCPs, unlike BWR RRPs, typically can not be isolated from thereactor coolant system following a seal failure. In addition, while a number of BWR RRP shaftshave cracked, several PWR RCP shafts have completely severed.
General Electric (GE) Nuclear Services Information Letter (SIL) 459-S2, issued October 21,
1991, informed GE boiling water reactor (BWR) owners of shaft cracking in RRPs. The root
 
cause was determined to be fatigue initiated by thermal stresses that, combined with
 
mechanical stresses, caused cracks to propagate. GE recommended countermeasures
 
including shaft vibration monitoring, inspection of shafts with greater than 80,000 hours of
 
service, and measures to reduce mechanical and thermal stresses.
 
At Hope Creek, RRPs had accumulated over 130,000 hours of service without pump shaft
 
inspections. The licensee had operated the B RRP for several refueling cycles with vibration
 
levels approaching vendor limits. During this time, the licensee also identified failed and
 
degraded RRP seals and concluded that the most likely causes of the failed and degraded RRP
 
seals were a possible bow in the pump shaft and low reliability of the seal purge system.
 
The licensees decision to restart following the fall 2004 refueling outage without correcting this
 
condition led to heightened public interest and prompted a close NRC review. The staff
 
evaluated site-specific technical details, related domestic and international operating
 
experience, and the generic safety aspects of vibration-related shaft and seal failure.
 
Circumferential cracking of RCP and RRP shafts had previously been reported at several
 
facilities including Sequoyah, Palo Verde, St. Lucie, and Grand Gulf. In addition, reactor
 
coolant pump shafts at Crystal River separated completely during operation on two occasions
 
(see IN 86-19 and IN 89-15).
 
The staff evaluated the licensees determination that the Hope Creek unit could be safely
 
returned to power with the existing pump shaft and the interim compensatory measures
 
implemented to provide reasonable assurance that a shaft failure could be detected in its
 
incipient stage and operators would take prompt action to prevent the occurrence of a potential
 
shaft and seal failure. The licensee committed to (1) replace the B pump shaft at the next
 
outage of sufficient duration and to (2) establish a comprehensive program of enhanced
 
continuous vibration monitoring to ensure timely detection of circumferential crack propagation
 
with proceduralized contingency actions for plant operators to act promptly at specified
 
administrative vibration limits to reduce pump speed or shut the pump down completely. The
 
same monitoring regime was implemented for the A RRP.
 
The Hope Creek licensee implemented a program to continuously monitor the synchronous
 
speed (1X) vibration amplitude, two times synchronous speed (2X) vibration amplitude, 1X
 
phase angle, and 2X phase angle. These parameters provide a more sensitive leading
 
indicator of circumferential crack initiation and propagation giving the operators enough time to
 
respond. Alarm limits were established using the ASME OM standard, "Reactor Coolant and
 
Recirculation Pump Condition Monitoring."
GE SIL 459 indicates that all Byron Jackson (now Flowserve) RRP shafts inspected have
 
shown some degree of thermally induced cracking. The cracking occurs near the pump
 
thermal barrier where the cold seal purge system water mixes with the hot reactor coolant
 
water. The cracks initiate as axial cracks in the pump shaft. Axial cracks are generally benign, grow slowly, and do not affect the operation of the pump. However, given sufficient mechanical
 
loads, the axial cracks can change direction and propagate circumferentially. The time it takes
 
to transition from slow-growing axial cracks to more rapidly growing circumferential cracks
 
depends on the magnitude of the mechanical loads on the pump shaft. It could take years. On
 
the other hand, circumferential shaft cracking can propagate rapidly and, if not detected early, may result in complete severance of the shaft.
 
Circumferential shaft cracking or shaft separation could result in pump damage and
 
degradation or failure of the pump seal package resulting in leakage of reactor coolant through
 
clearances around the upper portion of the pump shaft. However, at Crystal River - where the
 
only two instances of shaft failure occurred at domestic nuclear power plants - there was no
 
evidence of seal degradation. A loss-of-coolant accident can occur if leakage through the seals
 
of a RRP or RCP exceeds the capacity of the normal makeup systems. Thus circumferential
 
shaft cracking that leads to shaft or seal failure is a safety concern. As noted above, vibration-monitoring systems are available to detect circumferential cracking of
 
pump shafts. As circumferential cracks propagate, the stiffness of the pump shaft changes.
 
These changes are detectable through changes in the pump vibration signature prior to shaft
 
failure. Although overall pump vibration limits are necessary for assessing gaps and clearances
 
in the pump, they are not the most appropriate indicator of shaft cracking. Monitoring the 1X
 
and 2X steady-state vectors (1X and 2X amplitudes and phase angles) provides a better
 
indication of changes in shaft integrity resulting from circumferential crack propagation.
 
Licensees should be alert to the possibility of circumferential RCP or RRP shaft cracking and
 
should evaluate the information in this IN and determine what actions, if any, are prudent to
 
provide early detection of circumferential shaft cracking and prevent failure of RRP or RCP
 
shafts and shaft seals.
 
===GENERIC IMPLICATIONS===
A significant number (about half) of the BWR RRP pump shafts currently in service are older
 
and have more hours of operation than those at Hope Creek and many have not been
 
inspected as recommended in GE SIL 459-S2.
 
About a half-dozen BWR RRPs were identified as having higher vibration levels than Hope
 
Creek. Such issues would not necessarily be reported to the NRC. The staff contacted three
 
BWR licensees whose plants had been reported to have higher vibration levels than Hope
 
Creek. The three plants included Susquehanna Units 1 and 2, Peach Bottom Units 2 and 3, and Browns Ferry Units 2 and 3. The staff discussed with each licensee how it monitors pump
 
vibration, the vibration acceptance criteria used, and why the current vibration levels are
 
acceptable. These licensees indicated that they have either replaced their pump shafts (or will
 
in the near future) or are taking steps to monitor RRP vibration and have established
 
acceptance criteria to detect anomalous behavior.
 
Operating experience suggests that pressurized water reactor (PWR) RCPs are not immune to
 
vibration-related shaft and seal failure concerns similar to BWR RRP concerns. PWR RCP seal
 
failure can be more safety significant than BWR RRP seal failure because (1) PWR reactor
 
coolant systems operate at higher pressures, increasing the differential pressure across the
 
pump seals and (2) PWR RCPs, unlike BWR RRPs, typically can not be isolated from the
 
reactor coolant system following a seal failure. In addition, while a number of BWR RRP shafts
 
have cracked, several PWR RCP shafts have completely severed.


==CONTACT==
==CONTACT==
This information notice requires no specific action or written response. Please direct anyquestions about this matter to the technical contact(s) listed below or the appropriate Office ofNuclear Reactor Regulation (NRR) project manager./RA/Patrick L. Hiland, ChiefReactor Operations BranchDivision of Inspection Program ManagementOffice of Nuclear Reactor RegulationTechnical Contacts:William Poertner, NRRRoss Telson, NRR(301) 415-5787(301) 415-2256E-mail wkp@nrc.govE-mail rdt@nrc.gov Note: NRC generic communications may be found on the NRC public Web site,http://www.nrc.gov, under Electronic Reading Room/Document Collections.
This information notice requires no specific action or written response. Please direct any


IN 2005-08 
questions about this matter to the technical contact(s) listed below or the appropriate Office of
}}
 
Nuclear Reactor Regulation (NRR) project manager.
 
/RA/
                                            Patrick L. Hiland, Chief
 
Reactor Operations Branch
 
Division of Inspection Program Management
 
Office of Nuclear Reactor Regulation
 
Technical Contacts: William Poertner, NRR            Ross Telson, NRR
 
(301) 415-5787                (301) 415-2256 E-mail wkp@nrc.gov            E-mail rdt@nrc.gov
 
Note: NRC generic communications may be found on the NRC public Web site, http://www.nrc.gov, under Electronic Reading Room/Document Collections.
 
ML050730093 OFFICE OES:IROB:DIPM TECH EDITOR            EMEB:DE              SC:CI&T:EMEB  C:EMEB
 
NAME    RTelson        PKleene              WPoertner            DTerao        Eimbro
 
DATE    03/17/2005     03/22/2005          03/17/2005            03/18/2005    03/18/2005 OFFICE  D:DE            LPD1:DLPM            A:SC:OES:IROB:DIPM    C:IROB:DIPM
 
NAME    MMayfield      DSCollins (E- m ail) EJBenner              PLHiland
 
DATE    03/20/2005      04/05/2005          04/05/2005            04/05/2005}}


{{Information notice-Nav}}
{{Information notice-Nav}}

Latest revision as of 00:37, 24 November 2019

Monitoring Vibration to Detect Circumferential Cracking of Reactor Coolant Pump and Reactor Recirculation Pump Shafts
ML050730093
Person / Time
Site: Hope Creek PSEG icon.png
Issue date: 04/05/2005
From: Hiland P
NRC/NRR/DIPM/IROB
To:
Telson, R - NRR/DIPM/IROB - 415-2256
References
TAC MC6269 IN-05-008
Download: ML050730093 (5)
v • d • e


UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 April 5, 2005 NRC INFORMATION NOTICE 2005-08: MONITORING VIBRATION TO DETECT

CIRCUMFERENTIAL CRACKING OF REACTOR

COOLANT PUMP AND REACTOR

RECIRCULATION PUMP SHAFTS

ADDRESSEES

All holders of operating licenses for nuclear power reactors, except those who have

permanently ceased operations and have certified that fuel has been permanently removed

from the reactor vessel.

PURPOSE

The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice (IN) to alert

addressees to the importance of timely detection of circumferential cracking of reactor coolant

pump (RCP) and reactor recirculation pump (RRP) shafts to minimize the likelihood of

consequential shaft failures.

It is expected that recipients will review the information for applicability to their facilities and

consider actions, as appropriate, to avoid similar problems. However, the suggestions in this IN

are not NRC requirements; therefore, no specific action or written response is required.

DESCRIPTION OF CIRCUMSTANCES

General Electric (GE) Nuclear Services Information Letter (SIL) 459-S2, issued October 21,

1991, informed GE boiling water reactor (BWR) owners of shaft cracking in RRPs. The root

cause was determined to be fatigue initiated by thermal stresses that, combined with

mechanical stresses, caused cracks to propagate. GE recommended countermeasures

including shaft vibration monitoring, inspection of shafts with greater than 80,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> of

service, and measures to reduce mechanical and thermal stresses.

At Hope Creek, RRPs had accumulated over 130,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> of service without pump shaft

inspections. The licensee had operated the B RRP for several refueling cycles with vibration

levels approaching vendor limits. During this time, the licensee also identified failed and

degraded RRP seals and concluded that the most likely causes of the failed and degraded RRP

seals were a possible bow in the pump shaft and low reliability of the seal purge system.

The licensees decision to restart following the fall 2004 refueling outage without correcting this

condition led to heightened public interest and prompted a close NRC review. The staff

evaluated site-specific technical details, related domestic and international operating

experience, and the generic safety aspects of vibration-related shaft and seal failure.

Circumferential cracking of RCP and RRP shafts had previously been reported at several

facilities including Sequoyah, Palo Verde, St. Lucie, and Grand Gulf. In addition, reactor

coolant pump shafts at Crystal River separated completely during operation on two occasions

(see IN 86-19 and IN 89-15).

The staff evaluated the licensees determination that the Hope Creek unit could be safely

returned to power with the existing pump shaft and the interim compensatory measures

implemented to provide reasonable assurance that a shaft failure could be detected in its

incipient stage and operators would take prompt action to prevent the occurrence of a potential

shaft and seal failure. The licensee committed to (1) replace the B pump shaft at the next

outage of sufficient duration and to (2) establish a comprehensive program of enhanced

continuous vibration monitoring to ensure timely detection of circumferential crack propagation

with proceduralized contingency actions for plant operators to act promptly at specified

administrative vibration limits to reduce pump speed or shut the pump down completely. The

same monitoring regime was implemented for the A RRP.

The Hope Creek licensee implemented a program to continuously monitor the synchronous

speed (1X) vibration amplitude, two times synchronous speed (2X) vibration amplitude, 1X

phase angle, and 2X phase angle. These parameters provide a more sensitive leading

indicator of circumferential crack initiation and propagation giving the operators enough time to

respond. Alarm limits were established using the ASME OM standard, "Reactor Coolant and

Recirculation Pump Condition Monitoring."

GE SIL 459 indicates that all Byron Jackson (now Flowserve) RRP shafts inspected have

shown some degree of thermally induced cracking. The cracking occurs near the pump

thermal barrier where the cold seal purge system water mixes with the hot reactor coolant

water. The cracks initiate as axial cracks in the pump shaft. Axial cracks are generally benign, grow slowly, and do not affect the operation of the pump. However, given sufficient mechanical

loads, the axial cracks can change direction and propagate circumferentially. The time it takes

to transition from slow-growing axial cracks to more rapidly growing circumferential cracks

depends on the magnitude of the mechanical loads on the pump shaft. It could take years. On

the other hand, circumferential shaft cracking can propagate rapidly and, if not detected early, may result in complete severance of the shaft.

Circumferential shaft cracking or shaft separation could result in pump damage and

degradation or failure of the pump seal package resulting in leakage of reactor coolant through

clearances around the upper portion of the pump shaft. However, at Crystal River - where the

only two instances of shaft failure occurred at domestic nuclear power plants - there was no

evidence of seal degradation. A loss-of-coolant accident can occur if leakage through the seals

of a RRP or RCP exceeds the capacity of the normal makeup systems. Thus circumferential

shaft cracking that leads to shaft or seal failure is a safety concern. As noted above, vibration-monitoring systems are available to detect circumferential cracking of

pump shafts. As circumferential cracks propagate, the stiffness of the pump shaft changes.

These changes are detectable through changes in the pump vibration signature prior to shaft

failure. Although overall pump vibration limits are necessary for assessing gaps and clearances

in the pump, they are not the most appropriate indicator of shaft cracking. Monitoring the 1X

and 2X steady-state vectors (1X and 2X amplitudes and phase angles) provides a better

indication of changes in shaft integrity resulting from circumferential crack propagation.

Licensees should be alert to the possibility of circumferential RCP or RRP shaft cracking and

should evaluate the information in this IN and determine what actions, if any, are prudent to

provide early detection of circumferential shaft cracking and prevent failure of RRP or RCP

shafts and shaft seals.

GENERIC IMPLICATIONS

A significant number (about half) of the BWR RRP pump shafts currently in service are older

and have more hours of operation than those at Hope Creek and many have not been

inspected as recommended in GE SIL 459-S2.

About a half-dozen BWR RRPs were identified as having higher vibration levels than Hope

Creek. Such issues would not necessarily be reported to the NRC. The staff contacted three

BWR licensees whose plants had been reported to have higher vibration levels than Hope

Creek. The three plants included Susquehanna Units 1 and 2, Peach Bottom Units 2 and 3, and Browns Ferry Units 2 and 3. The staff discussed with each licensee how it monitors pump

vibration, the vibration acceptance criteria used, and why the current vibration levels are

acceptable. These licensees indicated that they have either replaced their pump shafts (or will

in the near future) or are taking steps to monitor RRP vibration and have established

acceptance criteria to detect anomalous behavior.

Operating experience suggests that pressurized water reactor (PWR) RCPs are not immune to

vibration-related shaft and seal failure concerns similar to BWR RRP concerns. PWR RCP seal

failure can be more safety significant than BWR RRP seal failure because (1) PWR reactor

coolant systems operate at higher pressures, increasing the differential pressure across the

pump seals and (2) PWR RCPs, unlike BWR RRPs, typically can not be isolated from the

reactor coolant system following a seal failure. In addition, while a number of BWR RRP shafts

have cracked, several PWR RCP shafts have completely severed.

CONTACT

This information notice requires no specific action or written response. Please direct any

questions about this matter to the technical contact(s) listed below or the appropriate Office of

Nuclear Reactor Regulation (NRR) project manager.

/RA/

Patrick L. Hiland, Chief

Reactor Operations Branch

Division of Inspection Program Management

Office of Nuclear Reactor Regulation

Technical Contacts: William Poertner, NRR Ross Telson, NRR

(301) 415-5787 (301) 415-2256 E-mail wkp@nrc.gov E-mail rdt@nrc.gov

Note: NRC generic communications may be found on the NRC public Web site, http://www.nrc.gov, under Electronic Reading Room/Document Collections.

ML050730093 OFFICE OES:IROB:DIPM TECH EDITOR EMEB:DE SC:CI&T:EMEB C:EMEB

NAME RTelson PKleene WPoertner DTerao Eimbro

DATE 03/17/2005 03/22/2005 03/17/2005 03/18/2005 03/18/2005 OFFICE D:DE LPD1:DLPM A:SC:OES:IROB:DIPM C:IROB:DIPM

NAME MMayfield DSCollins (E- m ail) EJBenner PLHiland

DATE 03/20/2005 04/05/2005 04/05/2005 04/05/2005


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