Information Notice 1997-10, Liner Plate Corrosion in Concrete Containments: Difference between revisions

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{{#Wiki_filter:K>UNITED STATES NUCLEAR REGULATORY
{{#Wiki_filter:K>
                                            UNITED STATES


COMMISSION
NUCLEAR REGULATORY COMMISSION


===OFFICE OF NUCLEAR REACTOR REGULATION===
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C. 20555-0001 March 13, 1997 NRC INFORMATION


NOTICE 97-10: LINER PLATE CORROSION
WASHINGTON, D.C. 20555-0001 March 13, 1997 NRC INFORMATION NOTICE 97-10: LINER PLATE CORROSION IN CONCRETE


===IN CONCRETE CONTAINMENTS===
CONTAINMENTS


==Addressees==
==Addressees==
All holders of operating
All holders of operating licenses or construction permits for power reactors.
 
licenses or construction
 
permits for power reactors.


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


Commission (NRC) is issuing this information
addressees to occurrences'of corrosion in the liner plates of reinforced and pre-stressed


notice to alert addressees
concrete containmnents, and to detrimental effects such corrosion could have on containment


to occurrences'of
reliability and availability under design-basis and beyond-design-basis events. It is expected


corrosion
that recipients will review this information for applicability to their facilities and consider


in the liner plates of reinforced
actions, as appropriate. However, suggestions contained in this information notice are not


and pre-stressed
NRC requirements; therefore, no specific action or written response is required.


concrete containmnents, and to detrimental
Background


effects such corrosion
Criterion 16 of the General Design Criteria of 10 CFR Part 50 requires that the reactor


could have on containment
containment and associated systems shall be provided to establish an essentially leaktight


reliability
barrier against the uncontrolled release of radioactivity to the environment. To meet this


and availability
leak-tightness requirement, the inside surfaces of concrete containments are lined with thin


under design-basis
metallic plates, generally between 6.2 mm (1/4 in.) and 9.5 mm (3/8 in.) thick. The liner


and beyond-design-basis
plates are attached to the concrete by means of stud anchors or structural rolled shapes or


events. It is expected that recipients
both.


will review this information
The design process assumes that the liner plates do not carry loads. However, the normal


for applicability
loads, such as from concrete shrinkage, creep and thermal changes, imposed on the


to their facilities
concrete containment structure are transferred to the liner plates through the anchorage


and consider actions, as appropriate.
system. Internal pressure and temperature loads are directly applied to the liner plate. Thus, under design-basis conditions, the liner plate could experience significant strains. Section III,
  Division 2 of the American Society of Mechanical Engineers (ASME) Boiler and Pressure


However, suggestions
Vessel Code (also called American Concrete Institute Standard 359), "Code for Concrete


contained
Reactor Vessels and Containments," allows liner tensile strains up to 0.004 cm/cm (inchfinch)
  of material for normal operating stresses, and up to 0.01 cm/cm (inch/inch) for stresses


in this information
resulting from the postulated environmental and accident conditions. American Society for


notice are not NRC requirements;
Testing and Materials (ASTM) Standard A516 (or equivalent) steel is typically used in the
therefore, no specific action or written response is required.Background


Criterion
P6E r4-E            0oTICE97-01/ 970313                              I


16 of the General Design Criteria of 10 CFR Part 50 requires that the reactor containment
ok                      'IFI.IllIEiliIEEP                                    ' '          IC


and associated
IN 97-10
                                                                            March 13, 1997 construction of containments. The minimum ultimate tensile strain of the liner material is


systems shall be provided to establish
0.2 cm/cm (inch/inch). Thus, there is a minimum safety factor of 20 above the theoretically


an essentially
calculated liner strains.


leaktight barrier against the uncontrolled
Any corrosion (metal thinning) of the liner plate could change the failure threshold of the liner


release of radioactivity
plate under a challenging environmental or accident condition. Thinning changes the


to the environment.
geometry of the liner plate, creating different transitions and strain concentration conditions.


To meet this leak-tightness
This may reduce the design margin of safety against postulated accident and environmental


requirement, the inside surfaces of concrete containments
loads.


are lined with thin metallic plates, generally
==Description of Circumstances==
Inspections of containment liners have shown various degrees of corrosion.


between 6.2 mm (1/4 in.) and 9.5 mm (3/8 in.) thick. The liner plates are attached to the concrete by means of stud anchors or structural
*      In January 1993, an NRC inspector pointed out corrosion of the drywell liner at Unit 2 of the Brunswick plant. The liner was corroded at various spots at the junction of the


rolled shapes or both.The design process assumes that the liner plates do not carry loads. However, the normal loads, such as from concrete shrinkage, creep and thermal changes, imposed on the concrete containment
base floor and the liner. A subsequent examination of Unit I showed similar


structure
corrosion.


are transferred
*      During the NRC staffs structural assessment review in June 1992, the staff noted


to the liner plates through the anchorage system. Internal pressure and temperature
peeled coating and spots of liner corrosion at Trojan (not operating) and at Beaver


loads are directly applied to the liner plate. Thus, under design-basis
Valley Unit 1.


conditions, the liner plate could experience
*      Before integrated leak rate testing of the containment at Salem Unit 2 in 1993, the


significant
licensee's staff noted minor corrosion of the containment liner.


strains. Section III, Division 2 of the American Society of Mechanical
*      During the NRC staff's structural assessment review in April 1992, discoloration of the


Engineers (ASME) Boiler and Pressure Vessel Code (also called American Concrete Institute
vertical portion of the containment liner was observed at an insulation joint at


Standard 359), "Code for Concrete Reactor Vessels and Containments," allows liner tensile strains up to 0.004 cm/cm (inchfinch)
Robinson Unit 2.
of material for normal operating


stresses, and up to 0.01 cm/cm (inch/inch)
Discussion
for stresses resulting


from the postulated
Of the five occurrences cited above, four (Trojan and Beaver Valley Unit 1, Salem Unit 2, and


environmental
Robinson Unit 2) were found to be benign from the standpoint of safety. However, the


and accident conditions.
licensees were sensitized to the conditions for future monitoring and repairs, as appropriate.


American Society for Testing and Materials (ASTM) Standard A516 (or equivalent)
Corrosion of the liner plate at Brunswick Units 1 and 2 was significant from the standpoint of
steel is typically


used in the P6E r4-E 0oTICE97-01/
safety. The sealing material along the circumference at the junction of the drywell.wall and
970313 I ok 'IFI.IllIEiliIEEP


' ' I C
the bottom floor had significantly degraded from the water accumulation at the junction. The


IN 97-10 March 13, 1997 construction
liner plate was found to have pitted significantly (as much as 50 percent of the original


of containments.
thickness) at various locations along the circumference. Before the restart of the two


The minimum ultimate tensile strain of the liner material is 0.2 cm/cm (inch/inch).
Brunswick units, the licensee cleaned the joint areas, repaired the pitted liner plate areas, and resealed the entire gap at the junction with dense silicone elastomer. The repair of the


Thus, there is a minimum safety factor of 20 above the theoretically
pitted areas consisted of (1) welding the pitted areas, (2) examining the repaired areas in


calculated
accordance with the ASME Section III, Division 2, and (3) recoating the repaired areas.


liner strains.Any corrosion (metal thinning)  
v)
of the liner plate could change the failure threshold
                                                                            IN 97-10
                                                                            March 13, 1997 Corrosion of a liner plate can occur at a number of places where the metal can be exposed


of the liner plate under a challenging
to moisture, or where moisture can condense (behind insulation) or accumulate. Potential


environmental
locations for liner plate corrosion are (1) the junction of the containment cylinder and


or accident condition.
intermediate floors and basemat concrete (PWRs and Mark IlIl BWRs), (2) the junction of the


Thinning changes the geometry of the liner plate, creating different
drywell and the base or intermediate concrete floors (Mark I, Mark II concrete containments),
(3) adjacent to crane girder rails and supports attached to the liner plate (concrete


transitions
containments), (4) water-soaked areas where carbon steel liner plate is used (Mark II and


and strain concentration
Mark Ill containments), and (5) behind insulation and ice-condenser baskets.


conditions.
An amendment to 10 CFR 50.55a became effective September 9, 1996. This amendment, by endorsing the use of Subsections IWE and IWL of Section Xl of the ASME Boiler and


This may reduce the design margin of safety against postulated
Pressure Vessel Code, provides detailed requirements for inservice inspection of containment


accident and environmental
structures. Inspection (which includes examination, evaluation, repair, and replacement) of


loads.Description
concrete containment liner plate in accordance with the 10 CFR 50.55a requirements


of Circumstances
involves consideration of the potential corrosion areas.


Inspections
This information notice requires no specific action or written response. If you have any


of containment
questions about information in this notice, please contact one of the technical contacts listed


liners have shown various degrees of corrosion.
below or the appropriate NRR project manager.


* In January 1993, an NRC inspector
Thomas T. Martin, Directo


pointed out corrosion
Division of Reactor Program Management


of the drywell liner at Unit 2 of the Brunswick
Office of Nuclear Reactor Regulation


plant. The liner was corroded at various spots at the junction of the base floor and the liner. A subsequent
Technical Contacts: Hans Ashar, NRR


examination
(301) 415-2851 E-mail: hga@nrc~gov


of Unit I showed similar corrosion.
R. A. Benedict, NRR


* During the NRC staffs structural
(301) 415-1157 E-mail: rabl@nrc.gov


assessment
Attachment: List of Recently Issued NRC Information Notices


review in June 1992, the staff noted peeled coating and spots of liner corrosion
===Ad                    74aI F4                u===


at Trojan (not operating)
K2 Attachment
and at Beaver Valley Unit 1.* Before integrated


leak rate testing of the containment
IN 97-10
                                                                        March 13, 1997 LIST OF RECENTLY ISSUED


at Salem Unit 2 in 1993, the licensee's
NRC INFORMATION NOTICES


staff noted minor corrosion
Information                                        Date of


of the containment
Notice No.            Subject                      Issuance    Issued to


liner.* During the NRC staff's structural
97-09            Inadequate Main Steam              03/12/97    All holders of OLs


assessment
Safety Valve (MSSV)                            or CPs for nuclear


review in April 1992, discoloration
Setpoints and Perform-                        power reactors


of the vertical portion of the containment
ance Issues Associated


liner was observed at an insulation
with Long MSSV Inlet


joint at Robinson Unit 2.Discussion
Piping


Of the five occurrences
97-08            Potential Failures                03/12/97  All holders of OLs


cited above, four (Trojan and Beaver Valley Unit 1, Salem Unit 2, and Robinson Unit 2) were found to be benign from the standpoint
for General Electric                          or CPs for nuclear


of safety. However, the licensees
Magne-Blast Circuit                          power reactors


were sensitized
Breaker Subcomponents


to the conditions
97-07          Problems Identified                03/06/97    All holders of OLs


for future monitoring
During Generic Letter                          or CPs for nuclear


and repairs, as appropriate.
89-10 Closeout                                power reactors


Corrosion
Inspections
 
of the liner plate at Brunswick
 
Units 1 and 2 was significant
 
from the standpoint
 
of safety. The sealing material along the circumference
 
at the junction of the drywell.wall
 
and the bottom floor had significantly
 
degraded from the water accumulation
 
at the junction.
 
The liner plate was found to have pitted significantly (as much as 50 percent of the original thickness)
at various locations
 
along the circumference.
 
Before the restart of the two Brunswick
 
units, the licensee cleaned the joint areas, repaired the pitted liner plate areas, and resealed the entire gap at the junction with dense silicone elastomer.
 
The repair of the pitted areas consisted
 
of (1) welding the pitted areas, (2) examining
 
the repaired areas in accordance
 
with the ASME Section III, Division 2, and (3) recoating
 
the repaired areas.
 
v)IN 97-10 March 13, 1997 Corrosion
 
of a liner plate can occur at a number of places where the metal can be exposed to moisture, or where moisture can condense (behind insulation)
or accumulate.
 
Potential locations
 
for liner plate corrosion
 
are (1) the junction of the containment
 
cylinder and intermediate
 
floors and basemat concrete (PWRs and Mark IlIl BWRs), (2) the junction of the drywell and the base or intermediate
 
concrete floors (Mark I, Mark II concrete containments), (3) adjacent to crane girder rails and supports attached to the liner plate (concrete containments), (4) water-soaked
 
areas where carbon steel liner plate is used (Mark II and Mark Ill containments), and (5) behind insulation
 
and ice-condenser
 
baskets.An amendment
 
to 10 CFR 50.55a became effective
 
September
 
9, 1996. This amendment, by endorsing
 
the use of Subsections
 
IWE and IWL of Section Xl of the ASME Boiler and Pressure Vessel Code, provides detailed requirements
 
for inservice
 
inspection
 
of containment
 
structures.
 
Inspection (which includes examination, evaluation, repair, and replacement)
of concrete containment
 
liner plate in accordance
 
with the 10 CFR 50.55a requirements
 
involves consideration
 
of the potential
 
corrosion
 
areas.This information
 
notice requires no specific action or written response.
 
If you have any questions
 
about information
 
in this notice, please contact one of the technical
 
contacts listed below or the appropriate
 
NRR project manager.Thomas T. Martin, Directo Division of Reactor Program Management
 
===Office of Nuclear Reactor Regulation===
Technical
 
Contacts:
Hans Ashar, NRR (301) 415-2851 E-mail: hga@nrc~gov
 
R. A. Benedict, NRR (301) 415-1157 E-mail: rabl@nrc.gov
 
Attachment:
List of Recently Issued NRC Information
 
Notices Ad 74aI F4 u
 
===K2 Attachment===
IN 97-10 March 13, 1997 LIST OF RECENTLY ISSUED NRC INFORMATION
 
NOTICES Information
 
Date of Notice No. Subject Issuance Issued to 97-09 Inadequate
 
Main Steam Safety Valve (MSSV)Setpoints
 
and Perform-ance Issues Associated
 
with Long MSSV Inlet Piping 03/12/97 All holders of OLs or CPs for nuclear power reactors 97-08 Potential
 
Failures for General Electric Magne-Blast
 
===Circuit Breaker Subcomponents===
Problems Identified


During Generic Letter 89-10 Closeout Inspections
97-06          Weaknesses in Plant-              03/04/97    All holders of OLs


03/12/97 03/06/97 All holders of OLs or CPs for nuclear power reactors All holders of OLs or CPs for nuclear power reactors 97-07 97-06 91-85, Rev. 1 97-05 Weaknesses
Specific Emergency                            or CPs for nuclear


in Plant-Specific Emergency Operating
Operating Procedures                          power reactors with


Procedures
for Refilling the                              with once-through


for Refilling
Secondary Side of Dry                          steam generators


the Secondary
Once-Through Steam


Side of Dry Once-Through
Generators


===Steam Generators===
91-85,          Potential Failures of              02/27/97    All holders of OLs
Potential


Failures of Thermostatic
Rev. 1          Thermostatic Control                          or CPs for nuclear


Control Valves or Diesel Generator
Valves or Diesel                               power reactors


===Jacket Cooling Water Offsite Notification===
Generator Jacket
Capabilities


03/04/97 02/27/97 02/27/97 All holders of OLs or CPs for nuclear power reactors with with once-through
Cooling Water


steam generators
97-05          Offsite Notification              02/27/97    All holders of OLs


All holders of OLs or CPs for nuclear power reactors All holders of OLs or CPs for nuclear power reactors and test and research reactors OL = Operating
Capabilities                                  or CPs for nuclear


License CP = Construction
power reactors and


Permit
test and research


IN 97-10 March 13, 1997 Corrosion
reactors


of a liner plate can occur at a number of places where the metal can be exposed to moisture, or where moisture can condense (behind insulation)
OL = Operating License
or accumulate.


Potential locations
CP = Construction Permit


for liner plate corrosion
IN 97-10
                                                                                                      March 13, 1997 Corrosion of a liner plate can occur at a number of places where the metal can be exposed


are (1) the junction of the containment
to moisture, or where moisture can condense (behind insulation) or accumulate. Potential


cylinder and intermediate
locations for liner plate corrosion are (1) the junction of the containment cylinder and


floors and basemat concrete (PWRs and Mark Ill BWRs), (2) the junction of the drywell and the base or intermediate
intermediate floors and basemat concrete (PWRs and Mark Ill BWRs), (2) the junction of the


concrete floors (Mark I, Mark II concrete containments), (3) adjacent to crane girder rails and supports attached to the liner plate (concrete containments), (4) water-soaked
drywell and the base or intermediate concrete floors (Mark I, Mark II concrete containments),
            (3) adjacent to crane girder rails and supports attached to the liner plate (concrete


areas where carbon steel liner plate is used (Mark II and Mark Ill containments), and (5) behind insulation
containments), (4) water-soaked areas where carbon steel liner plate is used (Mark II and


and ice-condenser
Mark Ill containments), and (5) behind insulation and ice-condenser baskets.


baskets.An amendment
An amendment to 10 CFR 50.55a became effective September 9, 1996. This amendment, by endorsing the use of Subsections IWE and IWL of Section Xl of the ASME Boiler and


to 10 CFR 50.55a became effective
Pressure Vessel Code, provides detailed requirements for inservice inspection of containment


September
structures. Inspection (which includes examination, evaluation, repair, and replacement) of


9, 1996. This amendment, by endorsing
concrete containment liner plate in accordance with the 10 CFR 50.55a requirements


the use of Subsections
involves consideration of the potential corrosion areas.


IWE and IWL of Section Xl of the ASME Boiler and Pressure Vessel Code, provides detailed requirements
This information notice requires no specific action or written response. If you have any


for inservice
questions about information in this notice, please contact one of the technical contacts listed


inspection
below or the appropriate NRR project manager.


of containment
original signed by M.M. Slosson


structures.
Thomas T. Martin, Director


Inspection (which includes examination, evaluation, repair, and replacement)
Division of Reactor Program Management
of concrete containment


liner plate in accordance
Office of Nuclear Reactor Regulation


with the 10 CFR 50.55a requirements
Technical Contacts: Hans Ashar, NRR


involves consideration
(301) 415-2851 E-mail: hga@nrc.gov


of the potential
R. A. Benedict, NRR


corrosion
(301) 415-1157 E-mail: rabl@nrc.gov


areas.This information
Attachment: List of Recently Issued NRC Information Notices


notice requires no specific action or written response.
*SEE PREVIOUS CONCURRENCE


If you have any questions
DOCUMENT NAME: 97-10.IN Tech Editor has reviewed and concurred on 11/14/96 To receive a copy of this document, Indicate In the box: "C"u Copy without enclosures "E" w Copy with enclosures "N'
* No copy


about information
OFFICE      ECGG/PECB            E C:ECGB              l      C:PECB                      D:DRPM


in this notice, please contact one of the technical
NAME        HAshar*                    GBagchi*                AEChaffee*                1 Martin              i


contacts listed below or the appropriate
RABenedict*                                                                                <n


NRR project manager.original signed by M.M. Slosson Thomas T. Martin, Director Division of Reactor Program Management
DATE        11/13/96                  11/14/96                01/16/97                    03/      97 OFFICIAL RECORD COPY


===Office of Nuclear Reactor Regulation===
IN 97-xx
Technical


Contacts:
January, 1997 Corrosion of a liner plate can occur at a number of places where the metal can be exposed
Hans Ashar, NRR (301) 415-2851 E-mail: hga@nrc.gov


R. A. Benedict, NRR (301) 415-1157 E-mail: rabl@nrc.gov
to moisture, or where moisture can condense (behind insulation) or accumulate. Potential


Attachment:
locations for liner plate corrosion are (1) the junction of the containment cylinder and
List of Recently Issued NRC Information


Notices*SEE PREVIOUS CONCURRENCE
intermediate floors and basemat concrete (PWRs and Mark IlIl BWRs), (2) the junction of the


DOCUMENT NAME: 97-10.IN Tech Editor has reviewed and concurred
drywell and the base or intermediate concrete floors (Mark I, Mark II concrete containments),
            (3) adjacent to crane girder rails and supports attached to the liner plate (concrete


on 11/14/96 To receive a copy of this document, Indicate In the box: "C" u Copy without enclosures "E" w Copy with enclosures "N'
containments), (4) water-soaked areas where carbon steel liner plate is used (Mark II and
* No copy OFFICE ECGG/PECB


E C:ECGB l C:PECB D:DRPM NAME HAshar* GBagchi* AEChaffee*
Mark IlIl containments), and (5) behind insulation and ice-condenser baskets.
1 Martin i RABenedict*
<n DATE 11/13/96 11/14/96 01/16/97 03/ 97 OFFICIAL RECORD COPY


IN 97-xx January, 1997 Corrosion
An amendment to 10 CFR 50.55a became effective September 9, 1996. This amendment, by endorsing the use of Subsections IWE and IWL of Section Xl of the ASME Boiler and


of a liner plate can occur at a number of places where the metal can be exposed to moisture, or where moisture can condense (behind insulation)
Pressure Vessel Code, provides detailed requirements for inservice inspection of containment
or accumulate.


Potential locations
structures. Inspection (which includes examination, evaluation, repair, and replacement) of


for liner plate corrosion
concrete containment liner plate in accordance with the 10 CFR 50.55a requirements


are (1) the junction of the containment
involves consideration of the potential corrosion areas.


cylinder and intermediate
This information notice requires no specific action or written response. If you have any


floors and basemat concrete (PWRs and Mark IlIl BWRs), (2) the junction of the drywell and the base or intermediate
questions about information in this notice, please contact one of the technical contacts listed


concrete floors (Mark I, Mark II concrete containments), (3) adjacent to crane girder rails and supports attached to the liner plate (concrete containments), (4) water-soaked
below or the appropriate NRR project manager.


areas where carbon steel liner plate is used (Mark II and Mark IlIl containments), and (5) behind insulation
Thomas T. Martin, Director


and ice-condenser
Division of Reactor Program Management


baskets.An amendment
Office of Nuclear Reactor Regulation


to 10 CFR 50.55a became effective
Technical Contacts: Hans Ashar, NRR


September
(301) 415-2851 E-mail: hga@nrc.gov


9, 1996. This amendment, by endorsing
R. A. Benedict, NRR


the use of Subsections
(301) 415-1157 E-mail: rabl@nrc.gov


IWE and IWL of Section Xl of the ASME Boiler and Pressure Vessel Code, provides detailed requirements
Attachment: List of Recently Issued NRC Information Notices


for inservice
*SEE PREVIOUS CONCURRENCE
 
inspection
 
of containment
 
structures.
 
Inspection (which includes examination, evaluation, repair, and replacement)
of concrete containment
 
liner plate in accordance
 
with the 10 CFR 50.55a requirements
 
involves consideration
 
of the potential
 
corrosion
 
areas.This information
 
notice requires no specific action or written response.
 
If you have any questions
 
about information
 
in this notice, please contact one of the technical
 
contacts listed below or the appropriate
 
NRR project manager.Thomas T. Martin, Director Division of Reactor Program Management
 
===Office of Nuclear Reactor Regulation===
Technical
 
Contacts:
Hans Ashar, NRR (301) 415-2851 E-mail: hga@nrc.gov
 
R. A. Benedict, NRR (301) 415-1157 E-mail: rabl@nrc.gov
 
Attachment:
List of Recently Issued NRC Information
 
Notices*SEE PREVIOUS CONCURRENCE


DOCUMENT NAME: G:\RABILINERJIN.REV
DOCUMENT NAME: G:\RABILINERJIN.REV


To receive a copy of thls document, Indicate In the box: "C's Copy wbhout enclosures "E Copy wkh enclosue "N" -No copy OFFICE ECGG/PECB
To receive a copy of thls document, Indicate In the box: "C's Copy wbhout enclosures "E Copy wkh enclosue "N" - No copy
 
I E C:ECGB IC:PECB I D:DRPM IIIIIIlIIIl
 
NAME HAshar* GBagchi* AEChafffe
 
MartinLN RABenedict*
IW __DATE 11/13/96 11/14/96 jffWm i 2/3 /86q? -12/ /96 OFFICIAL RECORD COPY I 14/ 1 lhIN
 
' 'IN 96-xx November xx, 1996 the entire gap at the junction with dense silicone elastomer.
 
The repair of the pitted areas consisted
 
of (1) welding the pitted areas, (2) examining
 
the repaired areas in accordance
 
with the ASME Section III, Division 2, and (3) recoating
 
the repaired areas.Corrosion
 
of a liner plate can occur at a number of places where the metal can be exposed to moisture, or where moisture can condense (behind insulation)
or accumulate.
 
Potential
 
locations


for liner plate corrosion
OFFICE      ECGG/PECB        I E C:ECGB                              IC:PECB      I D:DRPM                IIIIIIlIIIl


are (1) the junction of the containment
NAME        HAshar*                    GBagchi*                AEChafffe                MartinLN


cylinder and intermediate
RABenedict*                                                                                      IW__
DATE        11/13/96                  11/14/96                    jffWm          i    2/3 /86q?-          12/ /96 OFFICIAL RECORD COPY


floors and basemat concrete (PWRs and Mark III BWRs), (2) the junction of the drywell and the base or intermediate
14/ 1 lhINI


concrete floors (Mark I, Mark II concrete containments), (3) adjacent to crane girder rails and supports attached to the liner plate (concrete
' 'IN                                                                                                    96-xx


containments), (4) water-soaked
November xx, 1996 the entire gap at the junction with dense silicone elastomer. The repair of


areas where carbon steel liner plate is used (Mark II and Mark III containments), and (5) behind insulation
the pitted areas consisted of (1)welding the pitted areas, (2)examining the


and ice-condenser
repaired areas in accordance with the ASME Section III, Division 2, and


baskets.An Amendment
(3) recoating the repaired areas.


to 10 CFR 50.55a that became effective
Corrosion of a liner plate can occur at a number of places where the metal can


on September
be exposed to moisture, or where moisture can condense (behind insulation) or


9. 1996, endorses the use of Subsections
accumulate. Potential locations for liner plate corrosion are (1)the


IWE and IWL of Section XI of the ASME Boiler and Pressure Vessel Code, with a few additional
junction of the containment cylinder and intermediate floors and basemat


requirements, for inservice inspection
concrete (PWRs and Mark III BWRs), (2)the junction of the drywell and the


of containment
base or intermediate concrete floors (Mark I, Mark II concrete containments),
            (3)adjacent to crane girder rails and supports attached to the liner plate


structures.
(concrete containments), (4)water-soaked areas where carbon steel liner plate


Inspection (which includes examination, evaluation, repair, and replacement)  
is used (Mark II and Mark III containments), and (5)behind insulation and
of concrete containment


liner plate in accordance
ice-condenser baskets.


with the 10 CFR 50.55a requirements
An Amendment to 10 CFR 50.55a that became effective on September 9. 1996, endorses the use of Subsections IWE and IWL of Section XI of the ASME Boiler


involves consideration
and Pressure Vessel Code, with a few additional requirements, for inservice


of the potential
inspection of containment structures. Inspection (which includes examination, evaluation, repair, and replacement) of concrete containment liner plate in


corrosion
accordance with the 10 CFR 50.55a requirements involves consideration of the


areas.This information
potential corrosion areas.


notice requires no specific action or written response.
This information notice requires no specific action or written response.                                         If


If you have any questions
you have any questions about information inthis notice. please contact one of


about information
the technical contacts listed below or the appropriate NRR project manager.


in this notice. please contact one of the technical
Thomas T. Martin, Director


contacts listed below or the appropriate
Division of Reactor Program Management


NRR project manager.Thomas T. Martin, Director Division of Reactor Program Management
Office of Nuclear Reactor Regulation


===Office of Nuclear Reactor Regulation===
Technical Contacts:            Hans Ashar, NRR                                        R.A. Benedict, NRR
Technical


Contacts:
(301) 415-2851                                         (301) 415-1157 E-mail: hga@nrc.gov                                    E-mail: rabl@nrc.gov
Hans Ashar, NRR R.A. Benedict, NRR (301) 415-2851 (301) 415-1157 E-mail: hga@nrc.gov


E-mail: rabl@nrc.gov
Attachment:         List of Recently Issued NRC Information Notices


Attachment:
*SEE PREVIOUS CONCURRENCE
List of Recently Issued NRC Information
 
Notices*SEE PREVIOUS CONCURRENCE


DOCUMENT NAME: G:\RAB1\LINERIN.REV
DOCUMENT NAME: G:\RAB1\LINERIN.REV


To receive a copy of this document, Indicate In the box: "Cab -Copy without enclosures "E' -Copy with enclosures "N" -No copy OFFICE ECGG/PECB
To receive a copy of this document, Indicate In the box: "Cab - Copy without enclosures "E'- Copy with enclosures "N" - No copy


I E C:CECGB C:PECB D:DRPM NAME HAshar* GBagchi* AEChaffee
OFFICE        ECGG/PECB        I E C:CECGB                       C:PECB                     D:DRPM


TTMartin RABenedi ct*DATE 11/13/96 11/14/96 12/ /96 iB 12/ /96 12/ /96 OFFICIAL RECORD COPY
NAME          HAshar*                  GBagchi*                  AEChaffee                  TTMartin


IN 96-xx November xx, 1996 the junction.
RABenedi ct*
DATE        11/13/96                   11/14/96                  12/ /96                iB  12/    /96              12/    /96 OFFICIAL RECORD COPY


The liner plate was found to have pitted significantly (as much as 50 percent of the original thickness)
IN 96-xx
at various locations


along the circumference.
November xx, 1996 the junction. The liner plate was found to have pitted significantly (as much


Before the restart of the two Brunswick
as 50 percent of the original thickness) at various locations along the


units, the licensee cleaned the joint areas, repaired the pitted liner plate areas, and resealed the entire gap at the junction with dense silicone elastomer.
circumference. Before the restart of the two Brunswick units, the licensee


The repair of the pitted areas consisted
cleaned the joint areas, repaired the pitted liner plate areas, and resealed


of (1) welding the pitted areas, (2) examining
the entire gap at the junction with dense silicone elastomer. The repair of


the repaired areas in accordance
the pitted areas consisted of (1)welding the pitted areas, (2)examining the


with the ASME Section III, Division 2. and (3)recoating
repaired areas in accordance with the ASME Section III, Division 2. and (3)
            recoating the repaired areas.


the repaired areas.Corrosion
Corrosion of a liner plate can occur at a number of places where the metal can


of a liner plate can occur at a number of places where the metal can be exposed to moisture, or where moisture can condense (behind insulation)  
be exposed to moisture, or where moisture can condense (behind insulation) or
or accumulate.


Potential
accumulate. Potential locations for liner plate corrosion are (1)the


locations
junction of the containment cylinder and intermediate floors and basemat


for liner plate corrosion
concrete (PWRs and Mark III BWRs), (2)the junction of the drywell and the


are (1) the junction of the containment
base or intermediate concrete floors (Mark I, Mark II concrete containments),
            (3)adjacent to crane girder rails and supports attached to the liner plate


cylinder and intermediate
(concrete containments), (4)water-soaked areas where carbon steel liner plate


floors and basemat concrete (PWRs and Mark III BWRs), (2) the junction of the drywell and the base or intermediate
is used (Mark II and Mark III containments). and (5)behind insulation and


concrete floors (Mark I, Mark II concrete containments), (3) adjacent to crane girder rails and supports attached to the liner plate (concrete
ice-condenser baskets.


containments), (4) water-soaked
An Amendment to 10 CFR 50.55a that became effective on September 9. 1996, endorses the use of Subsections IWE and IWL of Section XI of the ASME Boiler


areas where carbon steel liner plate is used (Mark II and Mark III containments).
and Pressure Vessel Code, with a few additional requirements, for inservice


and (5) behind insulation
inspection of containment structures. Inspection (which includes examination, evaluation, repair, and replacement) of concrete containment liner plate in


and ice-condenser
accordance with the 10 CFR 50.55a requirements involves consideration of the


baskets.An Amendment
potential corrosion areas.


to 10 CFR 50.55a that became effective
This information notice requires no specific action or written response. If


on September
you have any questions about information in this notice, please contact one of


9. 1996, endorses the use of Subsections
the technical contacts listed below or the appropriate NRR project manager.


IWE and IWL of Section XI of the ASME Boiler and Pressure Vessel Code, with a few additional
Thomas T. Martin, Director


requirements, for inservice inspection
Division of Reactor Program Management


of containment
Office of Nuclear Reactor Regulation


structures.
Technical Contacts:            Hans Ashar, NRR                                        R.A. Benedict, NRR


Inspection (which includes examination, evaluation, repair, and replacement)  
(301) 415-2851                                        (301) 415-1157 E-mail: hga@nrc.gov                                    E-mail: rabl@nrc.gov
of concrete containment


liner plate in accordance
Attachment:        List of Recently Issued NRC Information Notices


with the 10 CFR 50.55a requirements
*SEE PREVIOUS CONCURRENCE
 
involves consideration
 
of the potential
 
corrosion
 
areas.This information
 
notice requires no specific action or written response.
 
If you have any questions
 
about information
 
in this notice, please contact one of the technical
 
contacts listed below or the appropriate
 
NRR project manager.Thomas T. Martin, Director Division of Reactor Program Management
 
===Office of Nuclear Reactor Regulation===
Technical
 
Contacts:
Hans Ashar, NRR R.A. Benedict, NRR (301) 415-2851 (301) 415-1157 E-mail: hga@nrc.gov
 
E-mail: rabl@nrc.gov
 
Attachment:
List of Recently Issued NRC Information
 
Notices*SEE PREVIOUS CONCURRENCE


DOCUMENT NAME: G:\RAB1\LINERIN.REV
DOCUMENT NAME: G:\RAB1\LINERIN.REV


To recelve a copy of this document, Indicate In the box: "C" -Copy without enclosures "E" a Copy with enclosures "N" = No copy OFFICE ECGG/PECB
To recelve a copy of this document, Indicate In the box: "C" - Copy without enclosures "E" a Copy with enclosures "N" = No copy


I E C:ECGB C:PECB D:DRPM I INAME HAshar* GBagchi* AEChaffee
OFFICE      ECGG/PECB          I E     C:ECGB                   C:PECB                     D:DRPM                           I


TTMartin lRABenedict*w.F
INAME        HAshar*                    GBagchi*                  AEChaffee                  TTMartin


4 Ski
lRABenedict*w.F                                                                  4 Ski


IN 96-xx November xx, 1996 circumference.
IN 96-xx


Before the restart of the two Brunswick
November xx, 1996 circumference. Before the restart of the two Brunswick units, the licensee


units, the licensee cleaned the joint areas, repaired the pitted liner plate areas, and resealed the entire gap at the junction with dense silicone elastomer.
cleaned the joint areas, repaired the pitted liner plate areas, and resealed


The repair of the pitted areas consisted
the entire gap at the junction with dense silicone elastomer. The repair of


of (1) welding the pitted areas, (2) examining
the pitted areas consisted of (1)welding the pitted areas, (2) examining the


the repaired areas in accordance
repaired areas in accordance with the ASME Section III, Division 2, and (3)
            recoating the repaired areas.


with the ASME Section III, Division 2, and (3)recoating
Corrosion of a liner plate can occur at a number of places where the metal can


the repaired areas.Corrosion
be exposed to moisture, or where moisture can condense (behind insulation) or


of a liner plate can occur at a number of places where the metal can be exposed to moisture, or where moisture can condense (behind insulation)  
accumulate. Potential locations for liner plate corrosion are (1)the
or accumulate.


Potential
junction of the containment cylinder and intermediate floors and basemat


locations
concrete (PWRs and Mark III BWRs). (2) the junction of the drywell and the


for liner plate corrosion
base or intermediate concrete floors (Mark I. Mark II concrete containments),
            (3) adjacent to crane girder rails and supports attached to the liner plate


are (1) the junction of the containment
(concrete containments). (4)water-soaked areas where carbon steel liner plate


cylinder and intermediate
is used (Mark II and Mark III containments), and (5) behind insulation and


floors and basemat concrete (PWRs and Mark III BWRs). (2) the junction of the drywell and the base or intermediate
ice-condenser baskets.


concrete floors (Mark I. Mark II concrete containments), (3) adjacent to crane girder rails and supports attached to the liner plate (concrete
This information notice requires no specific action or written response. If


containments).
you have any questions about information in this notice, please contact one of


(4) water-soaked
the technical contacts listed below or the appropriate NRR project manager.


areas where carbon steel liner plate is used (Mark II and Mark III containments), and (5) behind insulation
Thomas T. Martin, Director


and ice-condenser
Division of Reactor Program Management


baskets.This information
Office of Nuclear Reactor Regulation


notice requires no specific action or written response.
Technical Contacts:              Hans Ashar. NRR


If you have any questions
(301) 415-2851 E-mail:      hga@nrc.gov


about information
R.A. Benedict, NRR


in this notice, please contact one of the technical
(301) 415-1157 E-mail:      rabl@nrc.gov


contacts listed below or the appropriate
Attachment: List of Recently Issued NRC Information Notices


NRR project manager.Thomas T. Martin, Director Division of Reactor Program Management
*SEE PREVIOUS CONCURRENCE


===Office of Nuclear Reactor Regulation===
DOCUMENT NAME: G:\RAB1\LINER IN.REV
Technical


Contacts:
To receive a copy of this document, Indicate In the box: "C" = Copy without enclosures "E"
Hans Ashar. NRR (301) 415-2851 E-mail: hga@nrc.gov
 
R.A. Benedict, NRR (301) 415-1157 E-mail: rabl@nrc.gov
 
Attachment:
List of Recently Issued NRC Information
 
Notices*SEE PREVIOUS CONCURRENCE
 
DOCUMENT NAME: G:\RAB1\LINER
 
IN.REV To receive a copy of this document, Indicate In the box: "C" = Copy without enclosures "E"
* Copy with enclosures "N"
* Copy with enclosures "N"
* No copy OFFICE ECGG/PECB
* No copy
 
I E C:ECGB lC:PECB D:DRPM NAME HAshar* GBagchi* AEChaffee
 
&#xa3; TTMartin RABenedict*
fiF DATE 11/13/96 11/14/96 11/ /96 q5SV 11/ /96 11/ /96 OFF ICI
 
IN 96-xx November xx, 1996 circumference.
 
Before the restart of the two Brunswick


units, the licensee cleaned the joint areas, repaired the pitted liner plate areas, and resealed the entire gap at the junction with dense silicone elastomer.
OFFICE        ECGG/PECB I E C:ECGB                          lC:PECB                          D:DRPM


The repair of the pitted areas consisted
NAME          HAshar*                  GBagchi*                AEChaffee          &#xa3;    TTMartin


of (1) welding the pitted areas in accordance
RABenedict*                                                            fiF


with the ASME Section VIII, "Rules for Construction
DATE          11/13/96                  11/14/96                11/    /96 q5SV            11/    /96              11/    /96 OFF ICI


of Pressure Vessels", (2) examining
IN 96-xx


the repaired areas in accordance
November xx, 1996 circumference. Before the restart of the two Brunswick units, the licensee


with the ASME Section III, Division 2, and (3) recoating
cleaned the joint areas, repaired the pitted liner plate areas, and resealed


the repaired areas.Corrosion
the entire gap at the junction with dense silicone elastomer. The repair of


of a liner plate can occur at a number of places where the metal can be exposed to moisture, or where moisture can condense (behind insulation)  
the pitted areas consisted of (1)welding the pitted areas in accordance
or accumulate.


Potential
with the ASME Section VIII, "Rules for Construction of Pressure Vessels",
            (2)examining the repaired areas in accordance with the ASME Section III,
            Division 2, and (3) recoating the repaired areas.


locations
Corrosion of a liner plate can occur at a number of places where the metal can


for liner plate corrosion
be exposed to moisture, or where moisture can condense (behind insulation) or


are (1) the junction of the containment
accumulate. Potential locations for liner plate corrosion are (1)the


cylinder and intermediate
junction of the containment cylinder and intermediate floors and basemat


floors and basemat concrete (PWRs and Mark III BWRs), (2) the junction of the drywell and the base or intermediate
concrete (PWRs and Mark III BWRs), (2)the junction of the drywell and the


concrete floors (Mark I, Mark II concrete containments), (3) adjacent to crane girder rails and supports attached to the liner plate (concrete
base or intermediate concrete floors (Mark I, Mark II concrete containments),
            (3)adjacent to crane girder rails and supports attached to the liner plate


containments), (4) water-soaked
(concrete containments), (4)water-soaked areas where carbon steel liner plate


areas where carbon steel liner plate is used (Mark II and Mark III containments), and (5) behind insulation
is used (Mark II and Mark III containments), and (5)behind insulation and


and ice-condenser
ice-condenser baskets.


baskets.This information
This information notice requires no specific action or written response. If


notice requires no specific action or written response.
you have any questions about information in this notice, please contact the


If you have any questions
technical contact listed below or the appropriate NRR project manager.


about information
Thomas T. Martin, Director


in this notice, please contact the technical
Division of Reactor Program Management


contact listed below or the appropriate
Office of Nuclear Reactor Regulation


NRR project manager.Thomas T. Martin, Director Division of Reactor Program Management
Technical Contacts:            Hans Ashar, NRR


===Office of Nuclear Reactor Regulation===
(301) 415-2851 E-mail: hga@nrc.gov
Technical


Contacts:
R.A. Benedict, NRR
Hans Ashar, NRR (301) 415-2851 E-mail: hga@nrc.gov


R.A. Benedict, NRR (301) 415-1157 E-mail: rabl@nrc.gov
(301) 415-1157 E-mail: rabl@nrc.gov


Attachment:  
Attachment: List of Recently Issued NRC Information Notices
List of Recently Issued NRC Information


Notices*SEE PREVIOUS CONCURRENCE
*SEE PREVIOUS CONCURRENCE


DOCUMENT NAME: G:\RAB1\LINER-IN.REV
DOCUMENT NAME: G:\RAB1\LINER-IN.REV


To receive a copy of this document, Indicate In Ul box: 'C' Copy without enclosures "E" Copy with enclosures "N' No copy OFFICE CGG/PECB I E C: l C:PECB D:DRPM OF_ _C _ _ _ _ _ _ _ __g 1 I _ _ __ __ __ _NAME HAshar* gQ AEChaffee
To receive a copy of this document, Indicate In Ul box: 'C' Copy without enclosures "E" Copy with enclosures "N' No copy
 
TTMartin RABenedict*
/K Ic DATE 11/13/96 , 11/ M996 611/ /96 11/ /96 11/ /96 OFFICIAL RECORD COPY


IN 96-xx November xx, 1996 circumference.
OFFICE


Before the restart of the two Brunswick
OF_
NAME


units, the licensee cleaned the joint areas, repaired the pitted liner plate areas, and resealed the entire gap at the junction with dense silicone elastomer.
_C


The repair of the pitted areas consisted
CGG/PECB


of (1) welding the pitted areas, (2) examining
_
              HAshar*
                      _    _
                                I E C:
                                _    _      _
                                                gQ


the repaired areas in accordance
1
                                                  _
                                                    l


with the ASME Section III. Division 2, and (3)recoating
__g  I C:PECB


the repaired areas.Corrosion
_
                                                              AEChaffee


of a liner plate can occur at a number of places where the metal can be exposed to moisture, or where moisture can condense (behind insulation)
_    __
or accumulate.
                                                                                          D:DRPM


Potential
__
                                                                                          TTMartin


locations
__          _
              RABenedict*              /K                                                                                  Ic


for liner plate corrosion
DATE          11/13/96        ,        11/ M996611/                  /96              11/    /96            11/    /96 OFFICIAL RECORD COPY


are (1) the junction of the containment
IN 96-xx


cylinder and intermediate
November xx, 1996 circumference. Before the restart of the two Brunswick units, the licensee


floors and basemat concrete (PWRs and Mark III BWRs), (2) the junction of the drywell and the base or intermediate
cleaned the joint areas, repaired the pitted liner plate areas, and resealed


concrete floors (Mark I. Mark II concrete containments), (3) adjacent to crane girder rails and supports attached to the liner plate (concrete
the entire gap at the junction with dense silicone elastomer. The repair of


containments), (4) water-soaked
the pitted areas consisted of (1)welding the pitted areas, (2)examining the


areas where carbon steel liner plate is used (Mark II and Mark III containments), and (5) behind insulation
repaired areas in accordance with the ASME Section III. Division 2, and (3)
            recoating the repaired areas.


and ice-condenser
Corrosion of a liner plate can occur at a number of places where the metal can


baskets.This information
be exposed to moisture, or where moisture can condense (behind insulation) or


notice requires no specific action or written response.
accumulate. Potential locations for liner plate corrosion are (1)the


If you have any questions
junction of the containment cylinder and intermediate floors and basemat


about information
concrete (PWRs and Mark III BWRs), (2) the junction of the drywell and the


in this notice, please contact the technical
base or intermediate concrete floors (Mark I. Mark II concrete containments),
            (3)adjacent to crane girder rails and supports attached to the liner plate


contact listed below or the appropriate
(concrete containments), (4) water-soaked areas where carbon steel liner plate


NRR project manager.Thomas T. Martin. Director Division of Reactor Program Management
is used (Mark II and Mark III containments), and (5) behind insulation and


===Office of Nuclear Reactor Regulation===
ice-condenser baskets.
Technical


Contacts:
This information notice requires no specific action or written response. If
Hans Ashar, NRR (301) 415-2851 E-mail: hga@nrc.gov


R.A. Benedict.
you have any questions about information in this notice, please contact the


NRR (301) 415-1157 E-mail: rabl@nrc.gov
technical contact listed below or the appropriate NRR project manager.


Attachment:
Thomas T. Martin. Director
List of Recently Issued NRC Information


Notices*SEE PREVIOUS CONCURRENCE
Division of Reactor Program Management


DOCUMENT NAME: G:\RAB1\LINERIN.REV
Office of Nuclear Reactor Regulation


To receive a copy of thIs document, Indicate In the box: SC" a Copy wihout enclosures "E' -Copy with enclosures "N" -No copy[OFFICE ECGG/PECB
Technical Contacts:              Hans Ashar, NRR


I E C: ECGB I :EC D:DRPM II NAME HAshar* GBagchi* AEChaffee
(301) 415-2851 E-mail: hga@nrc.gov


TTMartin RABenedict*
R.A. Benedict. NRR
DATE 11/13/96 11/14/96 11/ /96 11/ /96 11/ /96 OFFICIAL RECORD COPY


IN 96-xx November xx, 1996 the pitted areas consisted
(301) 415-1157 E-mail: rabl@nrc.gov


of (1) welding the pitted areas in accordance
Attachment: List of Recently Issued NRC Information Notices


with the ASME Section VIII, "Rules for Construction
*SEE PREVIOUS CONCURRENCE


of Pressure Vessels".
DOCUMENT NAME: G:\RAB1\LINERIN.REV
 
(2 examining
 
the repaired areas in accordance
 
with the ASME Section III. Divi on 2. and (3) recoating
 
the repaired areas.Corrosion


of a liner plate can occur at a number of places where the etal can be exposed to moisture, or where moisture can condense (behind ins ation) or accumulate.
To receive a copy of thIs document, Indicate In the box: SC" a Copy wihout enclosures "E' - Copy with enclosures "N" - No copy


Potential
[OFFICE        ECGG/PECB        I E C: ECGB              I        :EC                      D:DRPM          II


locations
NAME          HAshar*                  GBagchi*                AEChaffee                  TTMartin


for liner plate corrosion
RABenedict*
DATE          11/13/96                  11/14/96                11/ /96                    11/    /96              11/    /96 OFFICIAL RECORD COPY


are the junction of the containment
IN 96-xx


cylinder and intermediate
November xx, 1996 the pitted areas consisted of (1)welding the pitted areas in accordance


floors a 5basemat concrete (PWRs and Mark III BWRs), (2) the junction of the dr ell and the base or intermediate
with the ASME Section VIII, "Rules for Construction of Pressure Vessels". (2 examining the repaired areas in accordance with the ASME Section III. Divi on


concrete floors (Mark I, Mark II concrete containments), (3) adjacent to crane girder rails and supports attached the liner plate (concrete
2. and (3) recoating the repaired areas.


containments), (4) water-soaked
Corrosion of a liner plate can occur at a number of places where the etal can


areas where ca -on steel liner plate is used (Mark II and Mark III containments), and (5) b nd insulation
be exposed to moisture, or where moisture can condense (behind ins ation) or


and ice-condenser
accumulate.      Potential locations for liner plate corrosion are                              the


baskets.An Amendment
junction of the containment cylinder and intermediate floors a 5basemat


to 10 CFR 50.55a that became effecti on September
concrete (PWRs and Mark III BWRs), (2)the junction of the dr ell and the


9. 1996, endorses the use of Subsections
base or intermediate concrete floors (Mark I, Mark II concrete containments),
            (3)adjacent to crane girder rails and supports attached                                the liner plate


IWE and IWL of ction XI of the ASME Boiler and Pressure Vessel Code, with a few additiona
(concrete containments), (4)water-soaked areas where ca -onsteel liner plate


requirements, for inservice inspection
is used (Mark II and Mark III containments), and (5)b nd insulation and


of containment
ice-condenser baskets.


structures.
An Amendment to 10 CFR 50.55a that became effecti                          on September 9. 1996, endorses the use of Subsections IWE and IWL of                          ction XI of the ASME Boiler


Inspe ion (which includes examination, evaluation, repair, and replacement)
and Pressure Vessel Code, with a few additiona requirements, for inservice
of co rete containment


liner plate in accordance
inspection of containment structures. Inspe ion (which includes examination, evaluation, repair, and replacement) of co rete containment liner plate in


with the 10 CFR 50.55a requir nts involves consideration
accordance with the 10 CFR 50.55a requir nts involves consideration of the


of the potential
potential corrosion areas described abo .


corrosion
This information notice requires no ecific action or written response. If


areas described
you have any questions about inform ion in this notice, please contact the


abo .This information
technical contact listed below or he appropriate NRR project manager.


notice requires no ecific action or written response.
Thomas T. Martin, Director


If you have any questions
Division of Reactor Program Management


about inform ion in this notice, please contact the technical
Office of Nuclear Reactor Regulation


contact listed below or he appropriate
Technical Contacts:            H s Ashar, NRR


NRR project manager.Thomas T. Martin, Director Division of Reactor Program Management
01) 415-2851 E-mail: hga@nrc.gov


===Office of Nuclear Reactor Regulation===
R.A. Benedict, NRR
Technical


Contacts:
(301) 415-1157 E-mail: rabl@nrc.gov
H s Ashar, NRR 01) 415-2851 E-mail: hga@nrc.gov


R.A. Benedict, NRR (301) 415-1157 E-mail: rabl@nrc.gov
Attachment        List of Recently Issued NRC Information Notices


Attachment
DOCUMENT NAME:            RAB1\LINERIN.REV


List of Recently Issued NRC Information
To receive a copy of Is document, Indicate In the box: "C"- Copy without enclosures "E"u Copy with enclosures "N"* No copy


Notices DOCUMENT NAME: RAB1\LINERIN.REV
OFFICE        EC /PECB l              C:ECGB                TC:PECB                      D:DRPM


To receive a copy of Is document, Indicate In the box: "C" -Copy without enclosures "E" u Copy with enclosures "N"
NAME         Uyshar a                 GBagchi                 AEChaffee                 TTMartin                I
* No copy OFFICE EC /PECB l C:ECGB T C:PECB D:DRPM NAME Uyshar a GBagchi AEChaffee


TTMartin I l MABenedic
l MABenedic Pta~er.lk


Pta~er.lk DATE 11/ /96 11/ /96 11/ /96 11/ /96 11/ /96 OFFICIAL RECORD COPY}}
DATE         11/ /96                   11/ /96                 11/ /96                   11/   /96             11/     /96 OFFICIAL RECORD COPY}}


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

Latest revision as of 04:42, 24 November 2019

Liner Plate Corrosion in Concrete Containments
ML031050365
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, Three Mile Island, 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, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant  Entergy icon.png
Issue date: 03/13/1997
From: Martin T
Office of Nuclear Reactor Regulation
To:
References
IN-97-010, NUDOCS 9703140144
Download: ML031050365 (12)
v • d • e


K>

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555-0001 March 13, 1997 NRC INFORMATION NOTICE 97-10: LINER PLATE CORROSION IN CONCRETE

CONTAINMENTS

Addressees

All holders of operating licenses or construction permits for power reactors.

Purpose

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

addressees to occurrences'of corrosion in the liner plates of reinforced and pre-stressed

concrete containmnents, and to detrimental effects such corrosion could have on containment

reliability and availability under design-basis and beyond-design-basis events. It is expected

that recipients will review this information for applicability to their facilities and consider

actions, as appropriate. However, suggestions contained in this information notice are not

NRC requirements; therefore, no specific action or written response is required.

Background

Criterion 16 of the General Design Criteria of 10 CFR Part 50 requires that the reactor

containment and associated systems shall be provided to establish an essentially leaktight

barrier against the uncontrolled release of radioactivity to the environment. To meet this

leak-tightness requirement, the inside surfaces of concrete containments are lined with thin

metallic plates, generally between 6.2 mm (1/4 in.) and 9.5 mm (3/8 in.) thick. The liner

plates are attached to the concrete by means of stud anchors or structural rolled shapes or

both.

The design process assumes that the liner plates do not carry loads. However, the normal

loads, such as from concrete shrinkage, creep and thermal changes, imposed on the

concrete containment structure are transferred to the liner plates through the anchorage

system. Internal pressure and temperature loads are directly applied to the liner plate. Thus, under design-basis conditions, the liner plate could experience significant strains.Section III,

Division 2 of the American Society of Mechanical Engineers (ASME) Boiler and Pressure

Vessel Code (also called American Concrete Institute Standard 359), "Code for Concrete

Reactor Vessels and Containments," allows liner tensile strains up to 0.004 cm/cm (inchfinch)

of material for normal operating stresses, and up to 0.01 cm/cm (inch/inch) for stresses

resulting from the postulated environmental and accident conditions. American Society for

Testing and Materials (ASTM) Standard A516 (or equivalent) steel is typically used in the

P6E r4-E 0oTICE97-01/ 970313 I

ok 'IFI.IllIEiliIEEP ' ' IC

IN 97-10

March 13, 1997 construction of containments. The minimum ultimate tensile strain of the liner material is

0.2 cm/cm (inch/inch). Thus, there is a minimum safety factor of 20 above the theoretically

calculated liner strains.

Any corrosion (metal thinning) of the liner plate could change the failure threshold of the liner

plate under a challenging environmental or accident condition. Thinning changes the

geometry of the liner plate, creating different transitions and strain concentration conditions.

This may reduce the design margin of safety against postulated accident and environmental

loads.

Description of Circumstances

Inspections of containment liners have shown various degrees of corrosion.

  • In January 1993, an NRC inspector pointed out corrosion of the drywell liner at Unit 2 of the Brunswick plant. The liner was corroded at various spots at the junction of the

base floor and the liner. A subsequent examination of Unit I showed similar

corrosion.

  • During the NRC staffs structural assessment review in June 1992, the staff noted

peeled coating and spots of liner corrosion at Trojan (not operating) and at Beaver

Valley Unit 1.

  • Before integrated leak rate testing of the containment at Salem Unit 2 in 1993, the

licensee's staff noted minor corrosion of the containment liner.

  • During the NRC staff's structural assessment review in April 1992, discoloration of the

vertical portion of the containment liner was observed at an insulation joint at

Robinson Unit 2.

Discussion

Of the five occurrences cited above, four (Trojan and Beaver Valley Unit 1, Salem Unit 2, and

Robinson Unit 2) were found to be benign from the standpoint of safety. However, the

licensees were sensitized to the conditions for future monitoring and repairs, as appropriate.

Corrosion of the liner plate at Brunswick Units 1 and 2 was significant from the standpoint of

safety. The sealing material along the circumference at the junction of the drywell.wall and

the bottom floor had significantly degraded from the water accumulation at the junction. The

liner plate was found to have pitted significantly (as much as 50 percent of the original

thickness) at various locations along the circumference. Before the restart of the two

Brunswick units, the licensee cleaned the joint areas, repaired the pitted liner plate areas, and resealed the entire gap at the junction with dense silicone elastomer. The repair of the

pitted areas consisted of (1) welding the pitted areas, (2) examining the repaired areas in

accordance with the ASME Section III, Division 2, and (3) recoating the repaired areas.

v)

IN 97-10

March 13, 1997 Corrosion of a liner plate can occur at a number of places where the metal can be exposed

to moisture, or where moisture can condense (behind insulation) or accumulate. Potential

locations for liner plate corrosion are (1) the junction of the containment cylinder and

intermediate floors and basemat concrete (PWRs and Mark IlIl BWRs), (2) the junction of the

drywell and the base or intermediate concrete floors (Mark I, Mark II concrete containments),

(3) adjacent to crane girder rails and supports attached to the liner plate (concrete

containments), (4) water-soaked areas where carbon steel liner plate is used (Mark II and

Mark Ill containments), and (5) behind insulation and ice-condenser baskets.

An amendment to 10 CFR 50.55a became effective September 9, 1996. This amendment, by endorsing the use of Subsections IWE and IWL of Section Xl of the ASME Boiler and

Pressure Vessel Code, provides detailed requirements for inservice inspection of containment

structures. Inspection (which includes examination, evaluation, repair, and replacement) of

concrete containment liner plate in accordance with the 10 CFR 50.55a requirements

involves consideration of the potential corrosion areas.

This information notice requires no specific action or written response. If you have any

questions about information in this notice, please contact one of the technical contacts listed

below or the appropriate NRR project manager.

Thomas T. Martin, Directo

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical Contacts: Hans Ashar, NRR

(301) 415-2851 E-mail: hga@nrc~gov

R. A. Benedict, NRR

(301) 415-1157 E-mail: rabl@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

Ad 74aI F4 u

K2 Attachment

IN 97-10

March 13, 1997 LIST OF RECENTLY ISSUED

NRC INFORMATION NOTICES

Information Date of

Notice No. Subject Issuance Issued to

97-09 Inadequate Main Steam 03/12/97 All holders of OLs

Safety Valve (MSSV) or CPs for nuclear

Setpoints and Perform- power reactors

ance Issues Associated

with Long MSSV Inlet

Piping

97-08 Potential Failures 03/12/97 All holders of OLs

for General Electric or CPs for nuclear

Magne-Blast Circuit power reactors

Breaker Subcomponents

97-07 Problems Identified 03/06/97 All holders of OLs

During Generic Letter or CPs for nuclear

89-10 Closeout power reactors

Inspections

97-06 Weaknesses in Plant- 03/04/97 All holders of OLs

Specific Emergency or CPs for nuclear

Operating Procedures power reactors with

for Refilling the with once-through

Secondary Side of Dry steam generators

Once-Through Steam

Generators

91-85, Potential Failures of 02/27/97 All holders of OLs

Rev. 1 Thermostatic Control or CPs for nuclear

Valves or Diesel power reactors

Generator Jacket

Cooling Water

97-05 Offsite Notification 02/27/97 All holders of OLs

Capabilities or CPs for nuclear

power reactors and

test and research

reactors

OL = Operating License

CP = Construction Permit

IN 97-10

March 13, 1997 Corrosion of a liner plate can occur at a number of places where the metal can be exposed

to moisture, or where moisture can condense (behind insulation) or accumulate. Potential

locations for liner plate corrosion are (1) the junction of the containment cylinder and

intermediate floors and basemat concrete (PWRs and Mark Ill BWRs), (2) the junction of the

drywell and the base or intermediate concrete floors (Mark I, Mark II concrete containments),

(3) adjacent to crane girder rails and supports attached to the liner plate (concrete

containments), (4) water-soaked areas where carbon steel liner plate is used (Mark II and

Mark Ill containments), and (5) behind insulation and ice-condenser baskets.

An amendment to 10 CFR 50.55a became effective September 9, 1996. This amendment, by endorsing the use of Subsections IWE and IWL of Section Xl of the ASME Boiler and

Pressure Vessel Code, provides detailed requirements for inservice inspection of containment

structures. Inspection (which includes examination, evaluation, repair, and replacement) of

concrete containment liner plate in accordance with the 10 CFR 50.55a requirements

involves consideration of the potential corrosion areas.

This information notice requires no specific action or written response. If you have any

questions about information in this notice, please contact one of the technical contacts listed

below or the appropriate NRR project manager.

original signed by M.M. Slosson

Thomas T. Martin, Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical Contacts: Hans Ashar, NRR

(301) 415-2851 E-mail: hga@nrc.gov

R. A. Benedict, NRR

(301) 415-1157 E-mail: rabl@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

  • SEE PREVIOUS CONCURRENCE

DOCUMENT NAME: 97-10.IN Tech Editor has reviewed and concurred on 11/14/96 To receive a copy of this document, Indicate In the box: "C"u Copy without enclosures "E" w Copy with enclosures "N'

  • No copy

OFFICE ECGG/PECB E C:ECGB l C:PECB D:DRPM

NAME HAshar* GBagchi* AEChaffee* 1 Martin i

RABenedict* <n

DATE 11/13/96 11/14/96 01/16/97 03/ 97 OFFICIAL RECORD COPY

IN 97-xx

January, 1997 Corrosion of a liner plate can occur at a number of places where the metal can be exposed

to moisture, or where moisture can condense (behind insulation) or accumulate. Potential

locations for liner plate corrosion are (1) the junction of the containment cylinder and

intermediate floors and basemat concrete (PWRs and Mark IlIl BWRs), (2) the junction of the

drywell and the base or intermediate concrete floors (Mark I, Mark II concrete containments),

(3) adjacent to crane girder rails and supports attached to the liner plate (concrete

containments), (4) water-soaked areas where carbon steel liner plate is used (Mark II and

Mark IlIl containments), and (5) behind insulation and ice-condenser baskets.

An amendment to 10 CFR 50.55a became effective September 9, 1996. This amendment, by endorsing the use of Subsections IWE and IWL of Section Xl of the ASME Boiler and

Pressure Vessel Code, provides detailed requirements for inservice inspection of containment

structures. Inspection (which includes examination, evaluation, repair, and replacement) of

concrete containment liner plate in accordance with the 10 CFR 50.55a requirements

involves consideration of the potential corrosion areas.

This information notice requires no specific action or written response. If you have any

questions about information in this notice, please contact one of the technical contacts listed

below or the appropriate NRR project manager.

Thomas T. Martin, Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical Contacts: Hans Ashar, NRR

(301) 415-2851 E-mail: hga@nrc.gov

R. A. Benedict, NRR

(301) 415-1157 E-mail: rabl@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

  • SEE PREVIOUS CONCURRENCE

DOCUMENT NAME: G:\RABILINERJIN.REV

To receive a copy of thls document, Indicate In the box: "C's Copy wbhout enclosures "E Copy wkh enclosue "N" - No copy

OFFICE ECGG/PECB I E C:ECGB IC:PECB I D:DRPM IIIIIIlIIIl

NAME HAshar* GBagchi* AEChafffe MartinLN

RABenedict* IW__

DATE 11/13/96 11/14/96 jffWm i 2/3 /86q?- 12/ /96 OFFICIAL RECORD COPY

14/ 1 lhINI

' 'IN 96-xx

November xx, 1996 the entire gap at the junction with dense silicone elastomer. The repair of

the pitted areas consisted of (1)welding the pitted areas, (2)examining the

repaired areas in accordance with the ASME Section III, Division 2, and

(3) recoating the repaired areas.

Corrosion of a liner plate can occur at a number of places where the metal can

be exposed to moisture, or where moisture can condense (behind insulation) or

accumulate. Potential locations for liner plate corrosion are (1)the

junction of the containment cylinder and intermediate floors and basemat

concrete (PWRs and Mark III BWRs), (2)the junction of the drywell and the

base or intermediate concrete floors (Mark I, Mark II concrete containments),

(3)adjacent to crane girder rails and supports attached to the liner plate

(concrete containments), (4)water-soaked areas where carbon steel liner plate

is used (Mark II and Mark III containments), and (5)behind insulation and

ice-condenser baskets.

An Amendment to 10 CFR 50.55a that became effective on September 9. 1996, endorses the use of Subsections IWE and IWL of Section XI of the ASME Boiler

and Pressure Vessel Code, with a few additional requirements, for inservice

inspection of containment structures. Inspection (which includes examination, evaluation, repair, and replacement) of concrete containment liner plate in

accordance with the 10 CFR 50.55a requirements involves consideration of the

potential corrosion areas.

This information notice requires no specific action or written response. If

you have any questions about information inthis notice. please contact one of

the technical contacts listed below or the appropriate NRR project manager.

Thomas T. Martin, Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical Contacts: Hans Ashar, NRR R.A. Benedict, NRR

(301) 415-2851 (301) 415-1157 E-mail: hga@nrc.gov E-mail: rabl@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

  • SEE PREVIOUS CONCURRENCE

DOCUMENT NAME: G:\RAB1\LINERIN.REV

To receive a copy of this document, Indicate In the box: "Cab - Copy without enclosures "E'- Copy with enclosures "N" - No copy

OFFICE ECGG/PECB I E C:CECGB C:PECB D:DRPM

NAME HAshar* GBagchi* AEChaffee TTMartin

RABenedi ct*

DATE 11/13/96 11/14/96 12/ /96 iB 12/ /96 12/ /96 OFFICIAL RECORD COPY

IN 96-xx

November xx, 1996 the junction. The liner plate was found to have pitted significantly (as much

as 50 percent of the original thickness) at various locations along the

circumference. Before the restart of the two Brunswick units, the licensee

cleaned the joint areas, repaired the pitted liner plate areas, and resealed

the entire gap at the junction with dense silicone elastomer. The repair of

the pitted areas consisted of (1)welding the pitted areas, (2)examining the

repaired areas in accordance with the ASME Section III, Division 2. and (3)

recoating the repaired areas.

Corrosion of a liner plate can occur at a number of places where the metal can

be exposed to moisture, or where moisture can condense (behind insulation) or

accumulate. Potential locations for liner plate corrosion are (1)the

junction of the containment cylinder and intermediate floors and basemat

concrete (PWRs and Mark III BWRs), (2)the junction of the drywell and the

base or intermediate concrete floors (Mark I, Mark II concrete containments),

(3)adjacent to crane girder rails and supports attached to the liner plate

(concrete containments), (4)water-soaked areas where carbon steel liner plate

is used (Mark II and Mark III containments). and (5)behind insulation and

ice-condenser baskets.

An Amendment to 10 CFR 50.55a that became effective on September 9. 1996, endorses the use of Subsections IWE and IWL of Section XI of the ASME Boiler

and Pressure Vessel Code, with a few additional requirements, for inservice

inspection of containment structures. Inspection (which includes examination, evaluation, repair, and replacement) of concrete containment liner plate in

accordance with the 10 CFR 50.55a requirements involves consideration of the

potential corrosion areas.

This information notice requires no specific action or written response. If

you have any questions about information in this notice, please contact one of

the technical contacts listed below or the appropriate NRR project manager.

Thomas T. Martin, Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical Contacts: Hans Ashar, NRR R.A. Benedict, NRR

(301) 415-2851 (301) 415-1157 E-mail: hga@nrc.gov E-mail: rabl@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

  • SEE PREVIOUS CONCURRENCE

DOCUMENT NAME: G:\RAB1\LINERIN.REV

To recelve a copy of this document, Indicate In the box: "C" - Copy without enclosures "E" a Copy with enclosures "N" = No copy

OFFICE ECGG/PECB I E C:ECGB C:PECB D:DRPM I

INAME HAshar* GBagchi* AEChaffee TTMartin

lRABenedict*w.F 4 Ski

IN 96-xx

November xx, 1996 circumference. Before the restart of the two Brunswick units, the licensee

cleaned the joint areas, repaired the pitted liner plate areas, and resealed

the entire gap at the junction with dense silicone elastomer. The repair of

the pitted areas consisted of (1)welding the pitted areas, (2) examining the

repaired areas in accordance with the ASME Section III, Division 2, and (3)

recoating the repaired areas.

Corrosion of a liner plate can occur at a number of places where the metal can

be exposed to moisture, or where moisture can condense (behind insulation) or

accumulate. Potential locations for liner plate corrosion are (1)the

junction of the containment cylinder and intermediate floors and basemat

concrete (PWRs and Mark III BWRs). (2) the junction of the drywell and the

base or intermediate concrete floors (Mark I. Mark II concrete containments),

(3) adjacent to crane girder rails and supports attached to the liner plate

(concrete containments). (4)water-soaked areas where carbon steel liner plate

is used (Mark II and Mark III containments), and (5) behind insulation and

ice-condenser baskets.

This information notice requires no specific action or written response. If

you have any questions about information in this notice, please contact one of

the technical contacts listed below or the appropriate NRR project manager.

Thomas T. Martin, Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical Contacts: Hans Ashar. NRR

(301) 415-2851 E-mail: hga@nrc.gov

R.A. Benedict, NRR

(301) 415-1157 E-mail: rabl@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

  • SEE PREVIOUS CONCURRENCE

DOCUMENT NAME: G:\RAB1\LINER IN.REV

To receive a copy of this document, Indicate In the box: "C" = Copy without enclosures "E"

  • Copy with enclosures "N"
  • No copy

OFFICE ECGG/PECB I E C:ECGB lC:PECB D:DRPM

NAME HAshar* GBagchi* AEChaffee £ TTMartin

RABenedict* fiF

DATE 11/13/96 11/14/96 11/ /96 q5SV 11/ /96 11/ /96 OFF ICI

IN 96-xx

November xx, 1996 circumference. Before the restart of the two Brunswick units, the licensee

cleaned the joint areas, repaired the pitted liner plate areas, and resealed

the entire gap at the junction with dense silicone elastomer. The repair of

the pitted areas consisted of (1)welding the pitted areas in accordance

with the ASME Section VIII, "Rules for Construction of Pressure Vessels",

(2)examining the repaired areas in accordance with the ASME Section III,

Division 2, and (3) recoating the repaired areas.

Corrosion of a liner plate can occur at a number of places where the metal can

be exposed to moisture, or where moisture can condense (behind insulation) or

accumulate. Potential locations for liner plate corrosion are (1)the

junction of the containment cylinder and intermediate floors and basemat

concrete (PWRs and Mark III BWRs), (2)the junction of the drywell and the

base or intermediate concrete floors (Mark I, Mark II concrete containments),

(3)adjacent to crane girder rails and supports attached to the liner plate

(concrete containments), (4)water-soaked areas where carbon steel liner plate

is used (Mark II and Mark III containments), and (5)behind insulation and

ice-condenser baskets.

This information notice requires no specific action or written response. If

you have any questions about information in this notice, please contact the

technical contact listed below or the appropriate NRR project manager.

Thomas T. Martin, Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical Contacts: Hans Ashar, NRR

(301) 415-2851 E-mail: hga@nrc.gov

R.A. Benedict, NRR

(301) 415-1157 E-mail: rabl@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

  • SEE PREVIOUS CONCURRENCE

DOCUMENT NAME: G:\RAB1\LINER-IN.REV

To receive a copy of this document, Indicate In Ul box: 'C' Copy without enclosures "E" Copy with enclosures "N' No copy

OFFICE

OF_

NAME

_C

CGG/PECB

_

HAshar*

_ _

I E C:

_ _ _

gQ

1

_

l

__g I C:PECB

_

AEChaffee

_ __

D:DRPM

__

TTMartin

__ _

RABenedict* /K Ic

DATE 11/13/96 , 11/ M996611/ /96 11/ /96 11/ /96 OFFICIAL RECORD COPY

IN 96-xx

November xx, 1996 circumference. Before the restart of the two Brunswick units, the licensee

cleaned the joint areas, repaired the pitted liner plate areas, and resealed

the entire gap at the junction with dense silicone elastomer. The repair of

the pitted areas consisted of (1)welding the pitted areas, (2)examining the

repaired areas in accordance with the ASME Section III. Division 2, and (3)

recoating the repaired areas.

Corrosion of a liner plate can occur at a number of places where the metal can

be exposed to moisture, or where moisture can condense (behind insulation) or

accumulate. Potential locations for liner plate corrosion are (1)the

junction of the containment cylinder and intermediate floors and basemat

concrete (PWRs and Mark III BWRs), (2) the junction of the drywell and the

base or intermediate concrete floors (Mark I. Mark II concrete containments),

(3)adjacent to crane girder rails and supports attached to the liner plate

(concrete containments), (4) water-soaked areas where carbon steel liner plate

is used (Mark II and Mark III containments), and (5) behind insulation and

ice-condenser baskets.

This information notice requires no specific action or written response. If

you have any questions about information in this notice, please contact the

technical contact listed below or the appropriate NRR project manager.

Thomas T. Martin. Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical Contacts: Hans Ashar, NRR

(301) 415-2851 E-mail: hga@nrc.gov

R.A. Benedict. NRR

(301) 415-1157 E-mail: rabl@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

  • SEE PREVIOUS CONCURRENCE

DOCUMENT NAME: G:\RAB1\LINERIN.REV

To receive a copy of thIs document, Indicate In the box: SC" a Copy wihout enclosures "E' - Copy with enclosures "N" - No copy

[OFFICE ECGG/PECB I E C: ECGB I :EC D:DRPM II

NAME HAshar* GBagchi* AEChaffee TTMartin

RABenedict*

DATE 11/13/96 11/14/96 11/ /96 11/ /96 11/ /96 OFFICIAL RECORD COPY

IN 96-xx

November xx, 1996 the pitted areas consisted of (1)welding the pitted areas in accordance

with the ASME Section VIII, "Rules for Construction of Pressure Vessels". (2 examining the repaired areas in accordance with the ASME Section III. Divi on

2. and (3) recoating the repaired areas.

Corrosion of a liner plate can occur at a number of places where the etal can

be exposed to moisture, or where moisture can condense (behind ins ation) or

accumulate. Potential locations for liner plate corrosion are the

junction of the containment cylinder and intermediate floors a 5basemat

concrete (PWRs and Mark III BWRs), (2)the junction of the dr ell and the

base or intermediate concrete floors (Mark I, Mark II concrete containments),

(3)adjacent to crane girder rails and supports attached the liner plate

(concrete containments), (4)water-soaked areas where ca -onsteel liner plate

is used (Mark II and Mark III containments), and (5)b nd insulation and

ice-condenser baskets.

An Amendment to 10 CFR 50.55a that became effecti on September 9. 1996, endorses the use of Subsections IWE and IWL of ction XI of the ASME Boiler

and Pressure Vessel Code, with a few additiona requirements, for inservice

inspection of containment structures. Inspe ion (which includes examination, evaluation, repair, and replacement) of co rete containment liner plate in

accordance with the 10 CFR 50.55a requir nts involves consideration of the

potential corrosion areas described abo .

This information notice requires no ecific action or written response. If

you have any questions about inform ion in this notice, please contact the

technical contact listed below or he appropriate NRR project manager.

Thomas T. Martin, Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical Contacts: H s Ashar, NRR

01) 415-2851 E-mail: hga@nrc.gov

R.A. Benedict, NRR

(301) 415-1157 E-mail: rabl@nrc.gov

Attachment List of Recently Issued NRC Information Notices

DOCUMENT NAME: RAB1\LINERIN.REV

To receive a copy of Is document, Indicate In the box: "C"- Copy without enclosures "E"u Copy with enclosures "N"* No copy

OFFICE EC /PECB l C:ECGB TC:PECB D:DRPM

NAME Uyshar a GBagchi AEChaffee TTMartin I

l MABenedic Pta~er.lk

DATE 11/ /96 11/ /96 11/ /96 11/ /96 11/ /96 OFFICIAL RECORD COPY


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