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Category:NRC Information Notice
MONTHYEARInformation Notice 2010-12, Intervenors' Fifth Motion to Amend And/Or Supplement Proposed Contention No. 5 (Shield Building Cracking). Appendix VI: NRC FOIA Responses (B-51 Through B-53); Turkey Point Event Report; NRC Information Notic2012-08-17017 August 2012 Intervenors' Fifth Motion to Amend And/Or Supplement Proposed Contention No. 5 (Shield Building Cracking). Appendix VI: NRC FOIA Responses (B-51 Through B-53); Turkey Point Event Report; NRC Information Notice 2010-12: Containment Liner Cor Information Notice 2010-12, Intervenors' Fifth Motion to Amend and/or Supplement Proposed Contention No. 5 (Shield Building Cracking). Appendix VI: NRC FOIA Responses (B-51 Through B-53); Turkey Point Event Report; NRC Information Notice 2010-12: Contain2012-08-17017 August 2012 Intervenors' Fifth Motion to Amend and/or Supplement Proposed Contention No. 5 (Shield Building Cracking). Appendix VI: NRC FOIA Responses (B-51 Through B-53); Turkey Point Event Report; NRC Information Notice 2010-12: Containment Liner Cor Information Notice 2010-12, Intervenors' Fifth Motion to Amend and/or Supplement Proposed Contention No. 5 (Shield Building Cracking). Appendix VI: NRC FOIA Responses (B-51 Through B-53); Turkey Point Event Report; NRC Information Notice 2010-12: Con2012-08-17017 August 2012 Intervenors' Fifth Motion to Amend and/or Supplement Proposed Contention No. 5 (Shield Building Cracking). Appendix VI: NRC FOIA Responses (B-51 Through B-53); Turkey Point Event Report; NRC Information Notice 2010-12: Containment Liner Cor Information Notice 2002-13, E-mail from H. Nieh, Oedo to A. Levin, Ocm, Et Al., Issuance of Information Notice 2002-13, Fwd: E-mail from D. Pickett T Davis-Besse Communication Plan2002-04-0404 April 2002 E-mail from H. Nieh, Oedo to A. Levin, Ocm, Et Al., Issuance of Information Notice 2002-13, Fwd: E-mail from D. Pickett T Davis-Besse Communication Plan Information Notice 2002-11, Recent Experience with Degradation of Reactor Pressure Vessel Head2002-03-12012 March 2002 Recent Experience with Degradation of Reactor Pressure Vessel Head Information Notice 1999-28, Recall of Star Brand Fire Protection Sprinkler Heads1999-09-30030 September 1999 Recall of Star Brand Fire Protection Sprinkler Heads Information Notice 1999-27, Malfunction of Source Retraction Mechanism in Cobalt-60 Teletherapy Treatment Units1999-09-0202 September 1999 Malfunction of Source Retraction Mechanism in Cobalt-60 Teletherapy Treatment Units Information Notice 1999-26, Safety and Economic Consequences of Misleading Marketing Information1999-08-24024 August 1999 Safety and Economic Consequences of Misleading Marketing Information Information Notice 1999-25, Year 2000 Contingency Planning Activities1999-08-10010 August 1999 Year 2000 Contingency Planning Activities Information Notice 1999-24, Broad-Scope Licensees' Responsibilities for Reviewing and Approving Unregistered Sealed Sources and Devices1999-07-12012 July 1999 Broad-Scope Licensees' Responsibilities for Reviewing and Approving Unregistered Sealed Sources and Devices Information Notice 1999-23, Safety Concerns Related to Repeated Control Unit Failures of the Nucletron Classic Model High-Dose-Rate Remote Afterloading Brachytherapy Devices1999-07-0606 July 1999 Safety Concerns Related to Repeated Control Unit Failures of the Nucletron Classic Model High-Dose-Rate Remote Afterloading Brachytherapy Devices Information Notice 1999-22, 10CFR 34.43(a)(1); Effective Date for Radiographer Certification and Plans for Enforcement Discretion1999-06-25025 June 1999 10CFR 34.43(a)(1); Effective Date for Radiographer Certification and Plans for Enforcement Discretion Information Notice 1999-21, Recent Plant Events Caused by Human Performance Errors1999-06-25025 June 1999 Recent Plant Events Caused by Human Performance Errors Information Notice 1999-20, Contingency Planning for the Year 2000 Computer Problem1999-06-25025 June 1999 Contingency Planning for the Year 2000 Computer Problem Information Notice 1999-19, Rupture of the Shell Side of a Feedwater Heater at the Point Beach Nuclear Plant1999-06-23023 June 1999 Rupture of the Shell Side of a Feedwater Heater at the Point Beach Nuclear Plant Information Notice 1999-18, Update on Nrc'S Year 2000 Activities for Material Licensees and Fuel Cycle Licensees and Certificate Holders1999-06-14014 June 1999 Update on Nrc'S Year 2000 Activities for Material Licensees and Fuel Cycle Licensees and Certificate Holders Information Notice 1999-17, Problems Associated with Post-Fire Safe-Shutdown Circuit Analyses1999-06-0303 June 1999 Problems Associated with Post-Fire Safe-Shutdown Circuit Analyses Information Notice 1999-16, Federal Bureau of Investigation'S Nuclear Site Security Program1999-05-28028 May 1999 Federal Bureau of Investigation'S Nuclear Site Security Program Information Notice 1999-15, Misapplication for 10CFR Part 71 Transportation Shipping Cask Licensing Basis to 10CFR Part 50 Design Basis1999-05-27027 May 1999 Misapplication for 10CFR Part 71 Transportation Shipping Cask Licensing Basis to 10CFR Part 50 Design Basis Information Notice 1999-14, Unanticipated Reactor Water Draindown at Quad Cities Unit 2, Arkansas Nuclear One Unit 2, & FitzPatrick1999-05-0505 May 1999 Unanticipated Reactor Water Draindown at Quad Cities Unit 2, Arkansas Nuclear One Unit 2, & FitzPatrick Information Notice 1999-13, Insights from NRC Inspections of Low-and Medium-Voltage Circuit Breaker Maintenance Programs1999-04-29029 April 1999 Insights from NRC Inspections of Low-and Medium-Voltage Circuit Breaker Maintenance Programs Information Notice 1999-12, Year 2000 Computer Systems Readiness Audits1999-04-28028 April 1999 Year 2000 Computer Systems Readiness Audits Information Notice 1999-11, Incidents Involving the Use of Radioactive Iodine-1311999-04-16016 April 1999 Incidents Involving the Use of Radioactive Iodine-131 Information Notice 1999-08, Urine Specimen Adulteration1999-03-26026 March 1999 Urine Specimen Adulteration Information Notice 1999-09, Problems Encountered When Manually Editing Treatment Data on the Nucletron Microselectron-HDR (New) Model 105-9991999-03-24024 March 1999 Problems Encountered When Manually Editing Treatment Data on the Nucletron Microselectron-HDR (New) Model 105-999 Information Notice 1999-07, Failed Fire Protection Deluge Valves & Potential Testing Deficiencies in Preaction Sprinkler Systems1999-03-22022 March 1999 Failed Fire Protection Deluge Valves & Potential Testing Deficiencies in Preaction Sprinkler Systems Information Notice 1999-06, 1998 Enforcement Sanctions as a Result of Deliberate Violations of NRC Employee Protection Requirements1999-03-19019 March 1999 1998 Enforcement Sanctions as a Result of Deliberate Violations of NRC Employee Protection Requirements Information Notice 1999-06, 1998 Enforcement Sanctions As a Result of Deliberate Violations of NRC Employee Protection Requirements1999-03-19019 March 1999 1998 Enforcement Sanctions As a Result of Deliberate Violations of NRC Employee Protection Requirements Information Notice 1999-05, Inadvertent Discharge of Carbon Dioxide Fire Protection System and Gas Migration1999-03-0808 March 1999 Inadvertent Discharge of Carbon Dioxide Fire Protection System and Gas Migration Information Notice 1999-04, Unplanned Radiation Exposures to Radiographers, Resulting from Failures to Follow Proper Radiation Safety Procedures1999-03-0101 March 1999 Unplanned Radiation Exposures to Radiographers, Resulting from Failures to Follow Proper Radiation Safety Procedures Information Notice 1999-03, Exothermic Reactors Involving Dried Uranium Oxide Powder (Yellowcake)1999-01-29029 January 1999 Exothermic Reactors Involving Dried Uranium Oxide Powder (Yellowcake) Information Notice 1999-02, Guidance to Users on the Implementation of a New Single-Source Dose-Calculation Formalism and Revised Air-Kerma Strength Standard for Iodine-125 Sealed Sources1999-01-21021 January 1999 Guidance to Users on the Implementation of a New Single-Source Dose-Calculation Formalism and Revised Air-Kerma Strength Standard for Iodine-125 Sealed Sources Information Notice 1999-01, Deterioration of High-Efficiency Particulate Air Filters in a Pressurized Water Reactor Containment Fan Cooler Unit1999-01-20020 January 1999 Deterioration of High-Efficiency Particulate Air Filters in a Pressurized Water Reactor Containment Fan Cooler Unit Information Notice 1998-45, Cavitation Erosion of Letdown Line Orifices Resulting in Fatigue Cracking of Pipe Welds1998-12-15015 December 1998 Cavitation Erosion of Letdown Line Orifices Resulting in Fatigue Cracking of Pipe Welds Information Notice 1998-44, Ten-Year Inservice Inspection (ISI) Program Update for Licensees That Intend to Implement Risk-Informed ISI of Piping1998-12-10010 December 1998 Ten-Year Inservice Inspection (ISI) Program Update for Licensees That Intend to Implement Risk-Informed ISI of Piping Information Notice 1998-43, Leaks in Emergency Diesel Generator Lubricating Oil & Jacket Cooling Water Piping1998-12-0404 December 1998 Leaks in Emergency Diesel Generator Lubricating Oil & Jacket Cooling Water Piping Information Notice 1998-42, Implementation of 10 CFR 55.55a(g) Inservice Inspection Requirements1998-12-0101 December 1998 Implementation of 10 CFR 55.55a(g) Inservice Inspection Requirements Information Notice 1998-41, Spurious Shutdown of Emergency Diesel Generators from Design Oversight1998-11-20020 November 1998 Spurious Shutdown of Emergency Diesel Generators from Design Oversight Information Notice 1998-41, Spurious Shutdown of Emergency Diesel Generators From Design Oversight1998-11-20020 November 1998 Spurious Shutdown of Emergency Diesel Generators From Design Oversight Information Notice 1998-39, Summary of Fitness-for-Duty Program Performance Reports for Calendar Years 1996 and 19971998-10-30030 October 1998 Summary of Fitness-for-Duty Program Performance Reports for Calendar Years 1996 and 1997 Information Notice 1998-40, Design Deficiencies Can Lead to Reduced ECCS Pump Net Positive Suction Head During Design-Basis Accidents1998-10-26026 October 1998 Design Deficiencies Can Lead to Reduced ECCS Pump Net Positive Suction Head During Design-Basis Accidents Information Notice 1990-66, Incomplete Draining and Drying of Shipping Casks1998-10-25025 October 1998 Incomplete Draining and Drying of Shipping Casks Information Notice 1998-38, Metal-Clad Circuit Breaker Maintenance Issues Identified by NRC Inspections1998-10-15015 October 1998 Metal-Clad Circuit Breaker Maintenance Issues Identified by NRC Inspections Information Notice 1998-37, Eligibility of Operator License Applicants1998-10-0101 October 1998 Eligibility of Operator License Applicants Information Notice 1998-36, Inadequate or Poorly Controlled, Non-Safety-Related Maintenance Activities Unnecessarily Challenged Safety Systems1998-09-18018 September 1998 Inadequate or Poorly Controlled, Non-Safety-Related Maintenance Activities Unnecessarily Challenged Safety Systems Information Notice 1998-34, Configuration Control Errors1998-08-28028 August 1998 Configuration Control Errors Information Notice 1998-33, NRC Regulations Prohibit Agreements That Restrict or Discourage an Employee from Participating in Protected Activities1998-08-28028 August 1998 NRC Regulations Prohibit Agreements That Restrict or Discourage an Employee from Participating in Protected Activities Information Notice 1998-31, Fire Protection System Design Deficiencies and Common-Mode Flooding of Emergency Core Cooling System Rooms at Washington Nuclear Project Unit 21998-08-18018 August 1998 Fire Protection System Design Deficiencies and Common-Mode Flooding of Emergency Core Cooling System Rooms at Washington Nuclear Project Unit 2 Information Notice 1998-30, Effect of Year 2000 Computer Problem on NRC Licensees and Certificate Holders1998-08-12012 August 1998 Effect of Year 2000 Computer Problem on NRC Licensees and Certificate Holders Information Notice 1998-29, Predicted Increase in Fuel Rod Cladding Oxidation1998-08-0303 August 1998 Predicted Increase in Fuel Rod Cladding Oxidation 2012-08-17
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0 Q 0 0 0 9 0 3 h&@h. /-3!37 REG I V ED EXP-90i01536 UNITED STATES
MAR 0 5 1990 NUCLEAR REGULATORY COMMISSION
Dl-M OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D,C. 20555
...-
-
February 23, 1990
NRC INFORMATION NOTICE NO. 90-10: PRIMARY WATER STRESS CORROSION CRACKING
(PWSCC) OF INCONEL 600
Addressees
All holders o f operating licenses or construction permits for pressur zed water
reactors (PWRs) .
Purpose
This information notice is intended to alert addressees to potential problems
related to primary water stress corrosion cracking (PWSCC) of Inconel 600 that
has occurred in pressurizer heater thermal sleeves and instrument nozzles at
-several domestic and foreign PWR plants, It i s 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 do not constitute NRC requirements;
therefore, no specific action or written response is required.
Description of Circumstances
During the 1989 refueling outage at Calvert Cliffs Unit 2 (CC-2), visual
examination detected leakage in 20 pressurizer heater penetrations and 1 upper-level/pressure tap instrument nozzle. Leakage was indicated by the
presence of boric acid crystals at the penetrations and on the nozzle. Non- destructive examinations (liquid penetrant and eddy current examinations)
were performed on 28 thermal sleeves and 3 instrument nozzles. Crack indi- cations were reported in 24 thermal sleeves, including the 20 originally
identified to be leaking as well as the leaking nozzle. No crack indications
were found in the two lower instrument nozzles. The examinations showed that
all cracks in the sleeves and the nozzle were axially oriented with a maximum
length not greater than 1.5 inches. The mode of failure for the thermal sleeves
was identified as PWSCC.
The heater sleeves and the instrumentation nozzles were made of Inconel 600
tubing and bar materials, respectively, supplied by INCO. All thermal sleeves
were made in a high strength heat (NX8878) with a reported yield strength of
63.5 ksi. No chemical contaminants were found on the sleeve fracture surfaces.
A review of the fabrication records showed that all 120 thermal sleeves in CC-2 were reamed 3.5 inches from the top before welding and all but two were also
IrJ90-10
9002160093 Y
IN 90-10
February 23, 1990
Page 2 of.4, , ,
reamed after welding to facilitate the insertion of the heater rods. All
cracks in the sleeves were reported to be located inside the reamed :r&g,ioflI,,
either above or below the J-groove weld.
All instrument nozzles were made from heat no, NX8297 and its yield strength -
was reported to be 36 ksi, The licensee indicated that four upper instrument
nozzles, including the leaking one, had been extensively reworked when the
faulty J-groove welds were repaired. Based on the results of the investiga- tions, the licensee, Baltimore Gas and Electric (BG&E), postulated that the
leaking in the pressurizer thermal sleeves and the instrumentation nozzle
was due to PWSCC, The licensee is in the process o f removing a metallurgical
samp?e from the leaking instrument nozzle for failure analysis to identify
the mode of failure.
On February 27, 1986, a small leak (about 0.15 gpm) was observed on a
3/4-inch-diameter upper pressurizer level instrument nozzle at San Onofre
Nuclear Generating Station (SONGS) Unit 3 while the plant was in hot standby.
An axial flaw about 5/8 inch in length was identified on the inside diameter
surface o f the nozzle. The flaw appeared to originate from the end of the
nozzle inside the pressurizer and extended beyond the attachment weld (1/2 inch
in depth) approximately 1/8 inch into the annulus area of the nozzle assembly.
'The flawed nozzle was cut out, including the entire attachment weld, The
results of the metallurgical examination performed on the flawed nozzle
assembly indicated that the cracking was PWSCC.
In spring 1989, leakage from instrument nozzles was observed in two foreign
PWRs (one from each 1300-MW plant) when the hydrostatic pressure testing o f
the primary system was performed durlng the first refueling outage. The
instrument nozzles were made of Inconel 600 material. The installation
of the nozzles included mechanically rolling a portion of the nozzle into
the pressurizer she1 1. Nondestructive examinations (NDEs) were performed
on the leaking nozzles and found the cracks to be principally axial in
orientation; however, some circumferential cracking was observed. Destructive
examlnation o f these two leaking nozzles to identify the root causes has not
been completed. Additional NDEs were performed on all the instrument nozzles
of five 1300-MW PWRs. Crack indications were found in 12 instrument nozzles.
Discussion:
Extensive laboratory testing has shown that intergranular stress corrosion
cracking (IGSCC) requires the presence of the following three key elements:
an aggressive environment, susceptible material, and 'sufficient tensile
stresses for crack initiation and propagation. PWSCC refers to IGSCC in
the primary water environment of PWRs. The laboratory demonstration of
PWSCC in Inconel 600 was first reported by Coriou almost 30 years ago.
The studies of PWSCC in Inconel 600 have been documented in numerous
published reports. However, the mechanism for PWSCC in Inconel 600
is still not well understood. In PWRs, PWSCC o f Inconel 600 was first
reported in steam generator tubing.
I M 90-10
February 23, 1990 !
!
The cracking to date in the thermal sleeves and the instrument nozzles of the
domestic PWRs has been reported as being only axially oriented. The safety -
I
1 implication of an axial crack is not considered a significant threat to the
!
structural integrity of the components and most likely will result in a small
leak. However, limited circumferential cracking was reported in the instrument
<
nozzles of several foreign PWRs. The difference in the cracking morphology has
been attributed to the different type of mechanical working (rolling vs. reaming)
being performed on these nozzles and thermal sleeves. The appearance of the
crack in the rolled instrument nozzle is consistent with that observed in the
roll-expanded region of steam generator tubing, Circumferential cracking
poses a more serious safety concern because if it were to go undetected it
could lead to a structural failure of a component rather than to a limited
leak.
The reported cracking of the pressurizer thermal sleeves and the instrument
nozzle at Calvert Cliffs Unit 2 and the instrument nozzle at SONGS Unit 3 are the most current PWSCC events for Inconel 600 in domestic PWRs besides
the cracking problem associated with the steam generator tubin and plugs.
7
.The pressurizer thermal sleeves in Calvert Cliffs Unit 1 (CC-1 were also
made of the same heat of susceptible material, but the recent inspection
of the CC-1 pressurizer did not reveal any leaking or cracking of the thermal
sleeves. The licensee indicated that the major difference in the fabrication
of thermal sleeves between CC-1 and CC-2 is that the pre-installation reaming
operation was not performed on CC-1 sleeves. The Combustion Engineering Owners
Group (CEOG) performed an evaluation of pressurizer heater sleeve susceptibility
to PWSCC for plants designed by Combustion Engineering. The CEOG recomnended a
visual inspection program for the thermal sleeves. The inspection program for
the thermal sleeves varied, depending on the degree of susceptibility of the
sleeve materials. The sleeve susceptibility was rated by the elements described
z
above. The staff notes that at CC-2 the yield strength of the thermal sleeve
material is higher than that of the instrument nozzle material. However, PWSCC
occurred in both heats o f materials. This circumstance may indicate that the
yield strength of the material is not necessarily a reliable screening criterion
for PWSCC susceptibility. The CEOG is performing additional work to address.
PWSCC of Inconel 600. The CEOG programs include the following activities:
evaluations to gain better understanding of the cracking mechanism in
pressurizer thermal heater sleeves and instrument nozzles; an analytical
determination of a temperature profile for the heater sleeves; review of
the fabrication history of all Inconel 600 penetrations in the primary system
components; conduct of a test that is primarily a system leakage test on a
mock-up of the flawed components; and improvement of NDE methods for cracking
eva 1 ua t ion.
PWSCC of Inconel 600 is not a new phenomenon. However, very little special
attention has been given to the inspect.ion for PWSCC in Inconel 600 applica- tions other than that associated with the steam generator tubing. As a result
of the recently reported instances of PWSCC in the pressurizer heater thermal
sleeves and instrument nozzles in several domestic and foreign PWRs, it may be
prudent for licensees o f all PWRs to review their Inconel 600 applications in
i
the primary coolent pressure boundary, and when necessary, to iniplement an
augmented inspection program.
I N 90-10
February 23, 1990
Page 4 o f 4 This information n o t i c e r e q u i r e s no s p e c i f i c a c t i o n o r w r i t t e n response. I f
you have any questions about the i n f o r m a t i o n i n t h i s n o t i c e , please contact one
o f t h e t e c h n i c a l contacts l i s t e d below o r the appropriate NRR p r o j e c t manager.
-
W 5 - e '
h a r l e s E. Rossi. D r e c t o r
D i v i s i o n of Operational Events Assessment
O f f i c e of Nuclear Reactor Regulation
Technical Contacts: W i l l i a m H. KOO, NRR
(301) 492-0928 .
Robert A. Hermann, NRR
(301) 492-0911 A,,achment: L i s t o f Recently Issued NRC I n f i r m a t i o n Notices
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list | - Information Notice 1990-01, Importance of Proper Response to Self-Identified Violations by Licensees (12 January 1990, Topic: Uranium Hexafluoride)
- Information Notice 1990-02, Potential Degradation of Secondary Containment (22 January 1990)
- Information Notice 1990-03, Malfunction of Borg-Warner Bolted Bonnet Check Valves Caused by Failure of the Swing Arm (23 January 1990, Topic: Liquid penetrant)
- Information Notice 1990-04, Cracking of the Upper Shell-to-Transition Cone Girth Welds in Steam Generators, (26 January 1990, Topic: Nondestructive Examination, Thermal fatigue)
- Information Notice 1990-05, Inter-System Discharge of Reactor Coolant (29 January 1990)
- Information Notice 1990-06, Potential for Loss of Shutdown Cooling While at Low Reactor Coolant Levels (29 January 1990)
- Information Notice 1990-07, New Information Regarding Insulation Material Performance and Debris Blockage of PWR Containment Sumps (30 January 1990)
- Information Notice 1990-08, KR-85 Hazards from Decayed Fuel (1 February 1990)
- Information Notice 1990-08, KR-85 Hazards From Decayed Fuel (1 February 1990)
- Information Notice 1990-09, Extended Interim Storage of Low-Level Radioactive Waste by Fuel Cycle and Materials Licensees (5 February 1990, Topic: Decommissioning Funding Plan, Uranium Hexafluoride)
- Information Notice 1990-10, Primary Water Stress Corrosion Cracking (PWSCC) of Inconel 600 (23 February 1990, Topic: Boric Acid, Hydrostatic, Liquid penetrant)
- Information Notice 1990-10, Primary Water Stress Corrosion Cracking of Inconel 600 (23 February 1990, Topic: Boric Acid, Hydrostatic, Nondestructive Examination, Liquid penetrant)
- Information Notice 1990-11, Maintenance Deficiency Associated with Solenoid-Operated Valves (28 February 1990)
- Information Notice 1990-12, Monitoring or Interruption of Plant Communications (28 February 1990)
- Information Notice 1990-13, Importance of Review and Analysis of Safeguards Event Logs (5 March 1990)
- Information Notice 1990-14, Accidental Disposal of Radioactive Materials (6 March 1990, Topic: Brachytherapy)
- Information Notice 1990-15, Reciprocity Notification of Agreement State Radiation Control Directors Before Beginning Work in Agreement States (17 March 1990, Topic: Uranium Hexafluoride)
- Information Notice 1990-16, Compliance with New Decommissioning Rule (7 March 1990, Topic: Uranium Hexafluoride)
- Information Notice 1990-17, Weight and Center of Gravity Discrepancies for Copes-Vulcan Valves (8 March 1990, Topic: Earthquake)
- Information Notice 1990-18, Potential Problems with Crosby Safety Relief Valves Used on Diesel Generator Air Start Receiver Tanks (9 March 1990)
- Information Notice 1990-18, Potential Problems With Crosby Safety Relief Valves Used on Diesel Generator Air Start Receiver Tanks (9 March 1990)
- Information Notice 1990-19, Potential Loss of Effective Volume for Containment Recirculation Spray at PWR Facilities (14 March 1990)
- Information Notice 1990-20, Personnel Injuries Resulting from Improper Operation of Radwaste Incinerators (22 March 1990)
- Information Notice 1990-21, Potential Failure of Motor-Operated Butterfly Valves to Operate Because Valve Seat Friction was Underestimated (22 March 1990)
- Information Notice 1990-21, Potential Failure of Motor-Operated Butterfly Valves to Operate Because Valve Seat Friction Was Underestimated (22 March 1990)
- Information Notice 1990-22, Unanticipated Equipment Actuations Following Restoration of Power to Rosemount Transmitter Trip Units (23 March 1990, Topic: Reactor Vessel Water Level)
- Information Notice 1990-23, Improper Installation of Patel Conduit Seals (4 April 1990)
- Information Notice 1990-24, Transportation of Model Spec 2-T Radiographic Exposure Device (10 April 1990, Topic: Exclusive Use)
- Information Notice 1990-24, Transportation of Model SPEC 2-T Radiographic Exposure Device (10 April 1990, Topic: Exclusive Use)
- Information Notice 1990-25, Loss of Vital AC Power With Subsequent Reactor Coolant System Heat-Up (16 April 1990)
- Information Notice 1990-25, Loss of Vital AC Power with Subsequent Reactor Coolant System Heat-Up (16 April 1990)
- Information Notice 1990-26, Inadequate Flow of Essential Service Water to Room Coolers and Heat Exchangers for Engineered Safety-Feature Systems (24 April 1990)
- Information Notice 1990-27, Clarification of the Recent Revisions to the Regulatory Requirements for Packaging of Uranium Hexafluoride (UF6) for Transportation (30 April 1990, Topic: Uranium Hexafluoride)
- Information Notice 1990-28, Potential Error In High Steamline Flow Setpoint (30 April 1990)
- Information Notice 1990-28, Potential Error in High Steamline Flow Setpoint (30 April 1990)
- Information Notice 1990-29, Cracking of Cladding and Its Heat-Affected Zone in the Base Metal of a Reactor Vessel Head (30 April 1990, Topic: Nondestructive Examination, Liquid penetrant)
- Information Notice 1990-30, Ultrasonic Inspection Techniques for Dissimilar Metal Welds (1 May 1999, Topic: Dissimilar Metal Weld)
- Information Notice 1990-31, Update on Waste Form and High Integrity Container Topical Report Review Status, Identification of Problems with Cement Solidification, and Reporting of Waste Mishaps (4 May 1990, Topic: Process Control Program)
- Information Notice 1990-31, Update on Waste form and High Integrity Container Topical Report Review Status, Identification of Problems with Cement Solidification, and Reporting of Waste Mishaps (4 May 1990, Topic: Process Control Program)
- Information Notice 1990-32, Surface Crack and Subsurface Indications in the Weld of a Reactor Vessel Head (3 May 1990)
- Information Notice 1990-33, Sources of Unexpected Occupational Radiation Exposures at Spent Fuel Storage Pools (9 May 1990, Topic: Overexposure)
- Information Notice 1990-34, Response to False Siren Activations (10 May 1990, Topic: Siren)
- Information Notice 1990-35, Transportation of Type a Quantities of Non-Fissile Radioactive Materials (24 May 1990, Topic: Siren)
- Information Notice 1990-37, Sheared Pinion Gear-To-Shaft Keys in Limitorque Motor Actuators (24 May 1990)
- Information Notice 1990-38, License and Fee Requirements for Processing Financial Assurance Submittals for Decommissioning (6 November 1990, Topic: Authorized possession limits)
- Information Notice 1990-39, Recent Problems with Service Water Systems (1 June 1990)
- Information Notice 1990-40, Results of NRC-Sponsored Testing of Motor-Operated Valves (5 June 1990, Topic: Weak link)
- Information Notice 1990-41, Potential Failure of General Electric Magne-Blast Circuit Breakers and Ak Circuit Breakers (12 June 1990)
- Information Notice 1990-42, Failure of Electrical Power Equipment Due to Solar Magnetic Disturbances (19 June 1990)
- Information Notice 1990-43, Mechanical Interference with Thermal Trip Function in GE Molded-Case Circuit Breakers (29 June 1990)
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