Information Notice 1992-85, Potential Failures of Emergency Core Cooling Systems Caused by Foreign Material Blackage

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Potential Failures of Emergency Core Cooling Systems Caused by Foreign Material Blackage
ML031190717
Person / Time
Site: Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, 05000419, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant, Crane  Entergy icon.png
Issue date: 12/23/1992
From: Grimes B
Office of Nuclear Reactor Regulation
To:
References
IN-92-085, NUDOCS 9212170209
Download: ML031190717 (16)


- UNITED STATES NUCLEAR REGULATORY

COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 December 23, 1992 NRC INFORMATION

NOTICE 92-85: POTENTIAL

FAILURES OF EMERGENCY

CORE COOLING SYSTEMS CAUSED BY FOREIGN MATERIAL BLOCKAGE

Addressees

All holders of operating

licenses or construction

permits for nuclear power reactors.

Purpose

The U.S. Nuclear Regulatory

Commission (NRC) is issuing this information

notice to alert addressees

to the potential

failure of emergency

core cooling systems (ECCS) caused by foreign material blockage.

It is expected that recipients

will review the information

for applicability

to their facilities

and consider actions, as appropriate, to avoid similar problems.

However, suggestions

contained

in this information

notice are not NRC requirements;

therefore, no specific action or written response is required.Description

of Circumstances

H. B. Robinson Unit 2 On August 23, 1992, while the H. B. Robinson Nuclear Plant was in mode 4, hot shutdown, plant personnel

were performing

an operations

surveillance

test of the B safety injection (SI) pump. This test found that the recirculation

flow was 20 percent lower than it had been when it was last measured on July 12, 1992. Prompted by the resident inspector, the Carolina Power and Light Company (the licensee)

retested this pump on August 24, 1992, and found no recirculation

flow. The licensee also tested the A SI pump and found the recirculation

flow was 10 percent lower than when it was last measured.

The licensee declared both pumps inoperable

and took the unit to cold shutdown.On August 25, 1992, the licensee opened the B SI pump recirculation

line and removed a single piece of white plastic, about the size of a nickel, from the inline orifice.Previously, on July 8, 1992, the licensee had declared the B SI pump inoperable

after a quarterly

inservice

inspection

surveillance

test found that it was producing

a recirculation

flow of 11.4 Liters [3 gallons] per minute, rather than the required 132.5 Liters [35 gallons] per minute. On July 9, 1992, the licensee shut down the plant to determine

the cause of the low flow.The licensee removed the recirculation

line for the B SI pump and found that debris was obstructing

the inline orifice.9212170209 Pyt I ( /'a q9A Ac s e 0C20 28 IN 92-85 December 23, 1992 On July 12, 1992, after flushing the B SI pump and verifying

that recirculation

flows for both SI pumps were acceptable, the licensee returned the unit to service. The licensee also tested all other ECCS pumps that could have had contact with foreign material.

The licensee believed, prior to plant startup, that all debris had been removed.Point Beach Unit 2 On September

28, 1992, the Wisconsin

Electric Power Company (the licensee)performed

an ASME Section XI quarterly

test of containment

spray pumps and valves. During the test, the licensee noted that the discharge

pressure for the A train containment

spray pump was zero and that the pump was making an abnormal noise. The test was stopped and the pump was declared inoperable.

Upon disassembly

of the pump, a foam rubber plug was found blocking the impeller suction. The licensee removed the plug and retested the pump. The test was successfully

completed

and the pump was declared operable.Discussion

The licensee at H. B. Robinson determined

that the foreign material found in the SI system was a plastic material that had been used during a modification

of the Residual Heat Removal (RHR) system performed

in March through June 1992. The plastic material is manufactured

by DuPont and the trade name is Delrin-AF.

At the time of the RHR modification, the plastic material had been cut into-four

23=centimeter

[9-inch]-diameter,-circular

pieces for use-as weld purge dams. However, after completing

the modification, the licensee did not account for two of the four pieces. Delrin-AF

decomposes

at RCS system conditions

because of reaction with the water and thermal degradation.

The licensee suspected

that the purge dam pieces broke,. entered the RHR piping after breaking, and migrated into the refueling

water storage tank (RWST) and SI header during initial cavity draindown.

The licensee sent divers with cameras into the RWST to inspect for the plastic. The divers found three fragments

of Delrin-AF

plastic and also other pieces of miscellaneous

debris. The location and size of the recovered Delrin-AF

material agrees with the material migration

theory since all of the pieces were larger than those recovered

from the B SI pump in July and August.The licensee inspected

orifices for the SI pump minimum flow recirculation

lines and also visually inspected

piping, tanks, and components

to find and remove any foreign material.

Also, the licensee evaluated

the potential effect on other ECCS equipment

and concluded

that the ECCS equipment

would continue to be operable and reliable.a

IN 92-85 December 23, 1992 The licensee for Point Beach Unit 2 reviewed plant records and determined

that the plug was most likely left in the piping after modifications

were made to install full flow test lines in the RHR, containment

spray and safety injection

systems, during the 1991 refueling

outage. The NRC reviewed the event and determined

that one train of the safety injection

system piping was rendered inoperable

in the recirculation

mode because of the presence of the plug. This condition

had continued

for about a year and was caused by inadequate

foreign material exclusion

controls during the system modifications

made in the previous outage.The presence of small debris may not be detected by operational

or post modification

testing since blockages

may not appear immediately.

However, small debris may migrate into areas with smaller cross sections where the debris could collect and cause blockage after extended operation.

These examples illustrate

the consequences

of failure to ensure accountability

of all materials

that are used when safety systems are opened and to perform cleanliness

checks of all affected areas prior to system closure.Related Generic Communication

On November 21, 1989, the NRC issued Information

Notice (IN) 89-77, "Debris In Containment

Emergency

Sumps and Incorrect

Screen Configurations," which addressed

problems that could result from debris in containment

emergency sumps.This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.rnan K. Grimes, Director Division of Operating

Reactor Support Office of Nuclear Reactor Regulation

Technical

contact: Eric Benner, NRR (301) 504-1171 Attachment:

List of Recently Issued NRC Information

Notices

z-4 V a 0 z 0 V-v z C D -->n-_ _z 11 0-4U cmm U1 0 Cfl Ca/z Attachment

IN 92-85 December 23, 1992 Page I of 1 LIST OF RECENTLY ISSUED NRC INFORMATION

NOTICES Information

Notice No. Subject 92-84 Release of Patients Treated with Temporary Implants 88-23, Potential

for Gas Supp. 4 Binding of High-Pres- sure Safety Injection Pumps during A Design Basis Accident 92-83 Thrust Limits for Limitorque

Actuators and Potential

Over-stressing

of Motor-Operated Valves 92-82 Results of Thermo-Lag

330-1 Combustibility

Testing 92-81 Potential

Deficiency

of Electrical

Cables with Bonded Hypalon Jackets 92-80 Results of Thermo-Lag

330-1 Combustibility

Testing 92-79 Non-Power

Reactor Emergency

Event Response 92-78 Piston to Cylinder Liner Tin Smearing on Cooper-Bessemer

KSV Diesel Engines Vate of Issuance Issued to 12/17/92 All Nuclear Regulatory

Comnission

Medical (Licensees.

12/18/92 All holders of OLs or CPs for nuclear power reactors 12/17/92 All holders of OLs or CPs for nuclear power reactors 12/15/92 All holders of OLs or CPs for nuclear power reactors 12/11/92 All holders of OLs or CPs for nuclear power reactors.12/07/92 All holders of OLs or CPs for nuclear power reactors.12/01/92 All holders of OLs or CPs(for test and research reactors.11/30/92 All holders of OLs or CPs for nuclear power reactors.DL -Operating

License CP -Construction

Permit

'U IN 92-XX December xx, 1992 The licensee for Point Beach Unit 2 reviewed plant records and determined

that the plug was most likely left in the piping after modifications

were made to install full flow test lines-in the residual heat removal (RHR), containment

spray and safety injection

systems, during the 1991 refueling

outage. The NRC reviewed the event and determined

that one train of the safety injection system piping was rendered inoperable

in the recirculation

mode because of the presence of the plug. The NRC issued a Notice of Violation

and Proposed Imposition

of Civil Penalty in the amount of $75,000. This violation, which was classified

at Severity Level III, continued

for about a year and was caused by inadequate

foreign material exclusion

controls during the system modifications

made in the previous outage.The presence of small debris may not be detected by operational

or post modification

testing since blockages

may not appear immediately.

However, small debris may migrate into areas with smaller cross sections where the debris could collect and cause blockage after extended operation.

Whenever safety systems are opened, it is important

to ensure accountability

of any materials

that are used and to perform cleanliness

checks of all affected areas prior to system closure.Related Generic Communication

On November 21, 1989, the NRC issued Information

Notice (IN) 89-77, "Debris In Containment

Emergency

Sumps and Incorrect

Screen Configurations," which addressed

problems that could result from debris in containment

emergency sumps.This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, Director Division of Operating

Reactor Support Office of Nuclear Reactor Regulation

Technical

contact: Eric Benner, NRR (301) 504-1171 Attachment:

List of Recently Issued NRC Information

Notices*SEE PREVIOUS CONCURRENCE

OEAB:DORS

ASC/OEAB:DORS

ADM:RPB PM:PD2-1:DRPE

DGarcia* AGautam* JMain* BMozafari*

10/07/92 10/14/92 09/28/92 10/13/92 C/SRXB:DSSA

C/OEAB:DORS

OGCB:DORS

OE C/OGCB:DORS

D/DORS RJones* AChaffee*

JBirmingham , Lieberman*

GMarcus BGrimes 10/08/92 11/09/92 12////92 ~/ ' 2/09/92 12/1 i/927 12/ /92 DOCUMENT NAME: G:\DMG\INDEBRIS.DMG

4 I' J K)IN 92-XX December xx, 1992 The licensee for Point Beach Unit 2 reviewed plant records and determined

that the plug was most likely left in the piping after modifications

were made to install full flow test lines in the residual heat removal (RHR), containment

spray and safety injection

systems, during the 1991 refueling

outage. The NRC reviewed the event and determined

that one train of the safety injection system piping was rendered inoperable

in the recirculation

mode because of the presence of the plug. The NRC is issuing a Notice of Violation

and Proposed Imposition

of Civil Penalty in the amount of $75,000. This violation, which has been classified

at Severity Level III, continued

for about a year and was caused by inadequate

foreign material exclusion

controls during the system modifications

made in the previous outage.The presence of small debris may not be detected by operational

or post modification

testing since blockages

may not appear immediately.

However, small debris may migrate into areas with smaller cross sections where the debris could collect and cause blockage after extended operation.

Whenever safety systems are opened, it is important

to ensure accountability

of any materials

that are used and to perform cleanliness

checks of all affected areas prior to system closure.Related Generic Communication

On November 21, 1989, the NRC issued Information

Notice (IN) 89-77, "Debris In Containment

Emergency

Sumps and Incorrect

Screen Configurations," which addressed

problems that could result from debris in containment

emergency sumps.This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, Director Division of Operating

Reactor Support Office of Nuclear Reactor Regulation

Technical

contact: Eric Benner, NRR (301) 504-1171 Attachment:

List of Recently Issued NRC Information

Notices*SEE PREVIOUS CONCURRENCE

OEAB:DORS

ASC/OEAB:DORS

ADM:RPB PM:PD2-1:DRPE

DGarcia* AGautam* JMain* BMozafari*

10/07/92 10/14/92 09/28/92 10/13/92 C/SRXB:DSSA

C/OEAB:DORS

OGCB:DORS

OE AzK C/OGCB:DORS

RJones* AChaffee*

JBirmingham

JLieberman

GMarcus 10/08/92 11/09/92 12/ /92 12/f /92 12/ /92 DOCUMENT NAME: G:\DMG\INDEBRIS.DMG

D/DORS BGrimes 12/ /92 I I IN 92-XX December xx, 1992 pieces of miscellaneous

debris. The location and size of the recovered Delrin-AF

material agrees with the material migration

theory since all of the pieces were larger than those recovered

from the B SI pump in July and August.The licensee inspected

orifices for the SI pump minimum flow recirculation

lines, and visually inspected

piping, tanks, and components

to find and remove any foreign material.

Also, the licensee evaluated

the potential

effect on other ECCS equipment

and concluded

that the ECCS equipment

would continue to be operable and reliable.7-1- t-The staff notes thatl$resence

of small debris may not be detected by operational

or post-modification

testing since blockages

may not appear immediately.

However, small debris may migrate into areas with smaller cross sections where the debris can collect and cause blockage after extended operation.

Whenever safety systems are opened, it is important

to ensure accountability

of any materials

that are used and to perform'cleanliness

checks of all affected areas prior to system closure.Related Generic Communication

On November 21, 1989, the NRC issued Information

Notice (IN) 89-77, "Debris In Containment

Emergency

Sumps and Incorrect

Screen Configurations," which addressed

problems that could result from debris in containment

emergency sumps.This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, Director Division of Operating

Reactor Support Office of Nuclear Reactor Regulation

Technical

cor Attachment:

  • SEE PREVIOUS OEAB:DORS DGarcia*10/07/92 C/SRXB:DSSA

RJones*10/08/92 DOCUMENT NAME itact: Eric Benner, NRR (301) 504-1171 List of Recently Issued NRC Information

Notices CONCURRENCE

ASC/OEAB:DORS

ADM:RPB PM:PD2-1:DRPE

AGautam* JMain* BMozafari*

10/14/92 09/28/92 10/13/92 C/OEAB:DORS

OGCB:DORS

OE C/OGC AChaffee*

JBirmingham*

JLieberman*

GMarc 11/09/92 12/11/92 12/09/92 12/11 E: G:\DMG\INDEBRIS.DMG

B:DORS us*/92 D/DORS BGrimes 12/ /92

  • SEE PREVIOUS CONCURRENCE

OEAB:DORS DGarcia*10/07/92 ASC/OEAB:DORS

AGautam*10/14/92 ADM:RPB JMain*09/28/92 PM:PD2-1:DRPE

BMozafari*

10/13/92 C/SRXB:DSSA

RJones*10/08/92 DOCUMENT NAME: C/OEAB:DORS

C/OGCB:DORS

AChaffee*

GMarcus 11/09/92 / /92 G:\DMG\INDEBRIS.DMG

D/DORS BGrimes/ /92 IN 92-XX November xx, 1992 Related Generic Communication

On November 21, 1989, the NRC issued Information

Notice (IN) 89-77, 'Debris In Containment

Emergency

Sumps and Incorrect

Screen Configurations," in which it discussed

problems that could result from debris found in containment

emergency

sumps.This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, Director Division of Operating

Reactor Support Office of Nuclear Reactor Regulation

Technical

contacts: D. Garcia, NRR (301) 504-1170 Attachment:

List of Recently Issued NRC Information

Notices*SEE PREVIOUS CONCURRENCE

OEAB:DORS DGarcia*10/07/92 ASC/OEAB:DORS

AGautam*10/14/92 ADM:RPB JMain*09/28/92 PM:PD2-1:DRPE

BMozafari*

10/13/92 C/SRXB:DSSA

RJones*10/08/92 C/OE f DORS AChaffee Il /.ci/92 C/OGCB:DORS

GMarcus/ /92 I D/DORS BGrimes/ /92 DOCUMENT NAME: G:\DMG\INDEBRIS.DMC

IN 92-XX October xx, 1992 Related Generic Communication

On November 21, 1989, the NRC issued Information

Notice (IN) 89-77, "Debris In Containment

Emergency

Sumps and Incorrect

Screen Configurations," in which it discussed

problems that could result from debris found in containment

emergency

sumps.This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, Director Division of Operating

Reactor Support Office of Nuclear Reactor Regulation

Technical

contacts: D. Garcia, NRR (301) 504-1170 Attachment:

List of Recently Issued NRC Information

Notices*SEE PREVIOUS CONCURRENCE

OEAB:DORS DGarcia*10/07/92 ASC/OEAB:DgRS

/cLAGautamOC

/6 //~/ 92 ADM:RPB JMain*09/28/92 PM:PD2-1:DRPE

BMozafari*

10/13/92 C/SRXB:DSSA

RJones*10/08/92 C/OEAB:DORS

AChaffee/ /92 C/OGCB:DORS

GMarcus/ /92 D/DORS BGrimes/ /92 DOCUMENT NAME: G:\DEBRIS.DMG

IN 92-XX October xx, 1992 Related Generic Communication

On November 21, 1989, the NRC issued Information

Notice (IN) 89-77, 'Debris In Containment

Emergency

Sumps and Incorrect

Screen Configurations,'

in which it discussed

problems that could result from debris found in containment

emergency

sumps.This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, Director Division of Operating

Reactor Support Office of Nuclear Reactor Regulation

Technical

contacts: Denise M. Garcia, NRR (301) 504-1170 Attachment:

List of Recently Issued NRC Information

Notices*SEE PREVIOUS 0 : RS ,92 C/ SA RJon'es/0 /1(/92 CONCURRENCE

ASC/OEAB:DORS

AGautam/ /92 C/OEAB:DORS

AChaffee/ /92 ADM:RPB JMain*09/28/92 C/OGCB:DORS

GMarcus/ /92 PM:PD2-1 :DRP fl,_fv, BMozafari/0//13/92 D/DORS BGrimes/ /92 DOCUMENT NAME: G:\DEBRIS.DMG

This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Charles E. Rossi, Director Division of Operational

Events Assessment

Office of Nuclear Reactor Regulation

Technical

contacts: Denise M. Garcia, NRR (301) 504-1171 Attachment:

List of Recently Issued NRC Information

Notices OEAB:DOEA DGarcia/ /92 SC/OEAB:DOEA

AGautam/ /92 ADM:RPB JMain Q h 9/ 2J /f2 PM:PD2-1:DRPE

BMozafari/ /92 C/SRXB:DST

RJones/ /92 C/OEAB:DOEA

AChaffee/ /92 C/OGCB:DOEA

GMarcus/ /92 D/DOEA CRossi/ /92 DOCUMENT NAME: G:\DEBRIS.DMG

K-)UNITED STATES NUCLEAR REGULATORY

COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 December 23, 1992 NRC INFORMATION

NOTICE 92-85: POTENTIAL

FAILURES OF EMERGENCY

CORE COOLING SYSTEMS CAUSED BY FOREIGN MATERIAL BLOCKAGE

Addressees

All holders of operating

licenses or construction

permits for nuclear power reactors.

Purpose

The U.S. Nuclear Regulatory

Commission (NRC) is issuing this information

notice to alert addressees

to the potential

failure of emergency

core cooling systems (ECCS) caused by foreign material blockage.

It is expected that recipients

will review the information

for applicability

to their facilities

and consider actions, as appropriate, to avoid similar problems.

However, suggestions

contained

in this information

notice are not NRC requirements;

therefore, no specific action or written response is required.Description

of Circumstances

H. B. Robinson Unit 2 On August 23, 1992, while the H. B. Robinson Nuclear Plant was in mode 4, hot shutdown, plant personnel

were performing

an operations

surveillance

test of the B safety injection (SI) pump. This test found that the recirculation

flow was 20 percent lower than it had been when it was last measured on July 12, 1992. Prompted by the resident inspector, the Carolina Power and Light Company (the licensee)

retested this pump on August 24, 1992, and found no recirculation

flow. The licensee also tested the A SI pump and found the recirculation

flow was 10 percent lower than when it was last measured.

The licensee declared both pumps inoperable

and took the unit to cold shutdown.On August 25, 1992, the licensee opened the B SI pump recirculation

line and removed a single piece of white plastic, about the size of a nickel, from the inline orifice.Previously, on July 8, 1992, the licensee had declared the B SI pump inoperable

after a quarterly

inservice

inspection

surveillance

test found that it was producing

a recirculation

flow of 11.4 Liters [3 gallons] per minute, rather than the required 132.5 Liters [35 gallons] per minute. On July 9, 1992, the licensee shut down the plant to determine

the cause of the low flow.The licensee removed the recirculation

line for the B SI pump and found that debris was obstructing

the inline orifice.9212 0209

<-2 <off92-85 December 23, 1992 On July 12, 1992, after flushing the B SI pump and verifying

that recirculation

flows for both SI pumps were acceptable, the licensee returned the unit to service. The licensee also tested all other ECCS pumps that could have had contact with foreign material.

The licensee believed, prior to plant startup, that all debris had been removed.Point Beach Unit 2 On September

28, 1992, the Wisconsin

Electric Power Company (the licensee)performed

an ASME Section XI quarterly

test of containment

spray pumps and valves. During the test, the licensee noted that the discharge

pressure for the A train containment

spray pump was zero and that the pump was making an abnormal noise. The test was stopped and the pump was declared inoperable.

Upon disassembly

of the pump, a foam rubber plug was found blocking the impeller suction. The licensee removed the plug and retested the pump. The test was successfully

completed

and the pump was declared operable.Discussion

The licensee at H. B. Robinson determined

that the foreign material found in the SI system was a plastic material that had been used during a modification

of the Residual Heat Removal (RHR) system performed

in March through June 1992. The plastic material is manufactured

by DuPont and the trade name is Delrin-AF.

At the time of the RHR modification, the plastic material had been cut into four 23-centimeter

(9-inch] diameter, circular pieces for use as weld purge dams. However, after completing

the modification, the licensee did not account for two of the four pieces. Delrin-AF

decomposes

at RCS system conditions

because of reaction with the water and thermal degradation.

The licensee suspected

that the purge dam pieces broke, entered the RHR piping after breaking, and migrated into the refueling

water storage tank (RWST) and SI header during initial cavity draindown.

The licensee sent divers with cameras into the RWST to inspect for the plastic. The divers found three fragments

of Delrin-AF

plastic and also other pieces of miscellaneous

debris. The location and size of the recovered Delrin-AF

material agrees with the material migration

theory since all of the pieces were larger than those recovered

from the B SI pump in July and August.The licensee inspected

orifices for the SI pump minimum flow recirculation

lines and also visually inspected

piping, tanks, and components

to find and remove any foreign material.

Also, the licensee evaluated

the potential effect on other ECCS equipment

and concluded

that the ECCS equipment

would continue to be operable and reliable.

IN 92-85 December 23, 1992 The licensee for Point Beach Unit 2 reviewed plant records and determined

that the plug was most likely left in the piping after modifications

were made to install full flow test lines in the RHR, containment

spray and safety injection

systems, during the 1991 refueling

outage. The NRC reviewed the event and determined

that one train of the safety injection

system piping was rendered inoperable

in the recirculation

mode because of the presence of the plug. This condition

had continued

for about a year and was caused by inadequate

foreign material exclusion

controls during the system modifications

made in the previous outage.The presence of small debris may not be detected by operational

or post modification

testing since blockages

may not appear immediately.

However, small debris may migrate into areas with smaller cross sections where the debris could collect and cause blockage after extended operation.

These examples illustrate

the consequences

of failure to ensure accountability

of all materials

that are used when safety systems are opened and to perform cleanliness

checks of all affected areas prior to system closure.Related Generic Communication

On November 21, 1989, the NRC issued Information

Notice (IN) 89-77, "Debris In Containment

Emergency

Sumps and Incorrect

Screen Configurations," which addressed

problems that could result from debris in containment

emergency sumps.This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.rnan K. Grimes, Director Division of Operating

Reactor Support Office of Nuclear Reactor Regulation

Technical

contact: Eric Benner, NRR (301) 504-1171 Attachment:

List of Recently Issued NRC Information

Notices

l I 1 K" K-, I Attachment

IN 92-85 December 23, 1992 LIST OF RECENTLY ISSUED NRC INFORMATION

NOTICES Information

Date of Notice No. Subject Issuance Issued to 92-84 88-23, Supp. 4 92-83 92-82 92-81 92-80 Release of Patients Treated with Temporary Implants Potential

for Gas Binding of High-Pres- sure Safety Injection Pumps during A Design Basis Accident Thrust Limits for Limitorque

Actuators and Potential

Over-stressing

of Motor-Operated Valves Results of Thermo-Lag

330-1 Combustibility

Testing Potential

Deficiency

of Electrical

Cables with Bonded Hypalon Jackets Results of Thermo-Lag

330-1 Combustibility

Testing Non-Power

Reactor Emergency

Event Response Piston to Cylinder Liner Tin Smearing on Cooper-Bessemer

KSV Diesel Engines 12/17/92 12/18/92 12/17/92 12/15/92 12/11/92 12/07/92 12/01/92 11/30/92 All Nuclear Regulatory

Commission

Medical Licensees.

All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for test and research reactors.All holders of OLs or CPs for nuclear power reactors.92-79 92-78 OL = Operating

License CP = Construction

Permit