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| | issue date = 10/06/2003 | | | issue date = 10/06/2003 |
| | title = Unanalyzed Condition of Reactor Coolant Pump Seal Leakoff Line During Postulated Fire Scenarios or Station Blackout | | | title = Unanalyzed Condition of Reactor Coolant Pump Seal Leakoff Line During Postulated Fire Scenarios or Station Blackout |
| | author name = Beckner W D | | | author name = Beckner W |
| | author affiliation = NRC/NRR/DIPM | | | author affiliation = NRC/NRR/DIPM |
| | addressee name = | | | addressee name = |
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| | document type = NRC Information Notice | | | document type = NRC Information Notice |
| | page count = 7 | | | page count = 7 |
| | revision = 0
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| }} | | }} |
| {{#Wiki_filter: | | {{#Wiki_filter:UNITED STATES |
| [[Issue date::October 6, 2003]]
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| NRC INFORMATION NOTICE 2003-19:UNANALYZED CONDITION OF REACTORCOOLANT PUMP SEAL LEAKOFF LINE DURING POSTULATED FIRE SCENARIOS OR STATION BLACKOUT | | NUCLEAR REGULATORY COMMISSION |
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| | OFFICE OF NUCLEAR REACTOR REGULATION |
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| | WASHINGTON, DC 20555-0001 October 6, 2003 NRC INFORMATION NOTICE 2003-19: UNANALYZED CONDITION OF REACTOR |
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| | COOLANT PUMP SEAL LEAKOFF LINE DURING |
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| | POSTULATED FIRE SCENARIOS OR STATION |
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| | BLACKOUT |
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| ==Addressees== | | ==Addressees== |
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| ==Purpose== | | ==Purpose== |
| The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice (IN) to alertaddressees to the recent identification of an unanalyzed condition involving the design of the reactor coolant pump (RCP) seal leakoff lin The NRC anticipates that recipients will review the information for applicability to their facilities and consider taking appropriate action However, suggestions contained in this information notice are not NRC requirements; therefore, no specific action or written response is required. | | The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice (IN) to alert |
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| | addressees to the recent identification of an unanalyzed condition involving the design of the |
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| | reactor coolant pump (RCP) seal leakoff line. The NRC anticipates that recipients will review |
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| | the information for applicability to their facilities and consider taking appropriate actions. |
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| | However, suggestions contained in this information notice are not NRC requirements; therefore, no specific action or written response is required. |
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| ==Description of Circumstances== | | ==Description of Circumstances== |
| On January 13, 2003 the Millstone Unit 3 licensee identified that an over-pressurization of RCPseal leakoff lines could result from an extended loss of seal cooling following station blackout (SBO) scenarios or postulated fires in specific plant areas coincident with a loss of offsite powe Specifically, the licensee relies on operators to isolate the low pressure portion of the seal leakoff to prevent the line from over-pressurizin The licensee determined this expectation may not be achievable because the valve used to isolate the low pressure portion of the seal leakoff line is an air-operated valv This valve is designed to fail open upon loss of electrical power or instrument air, either of which could occur during a SBO or a loss of offsite power coincident with a postulated fire event.The seal return line for RCPs is designed to recover leakoff volume, at low pressure andtemperature, and return it to the volume control tank or charging pump suctio In the event of a fire in the cable spreading area, main control room, or instrument rack rooms, coincident with a loss of offsite power, a loss of RCP seal cooling could resul This situation can lead to a significant increase in RCP seal leakage which would increase the pressure and fluid temperature in the seal return lin This over pressurization could result in a pressure boundary failure of the seal return line, further increasing the RCP seal leakage beyond that assumed in the safe shutdown analysis. The resulting rupture would divert more of the credited boric acid storage tank (BAST) volumethan was assumed in the development of the licensee's fire safe-shutdown strategie Therefore, the strategies may not be adequate to achieve safe-shutdown.DiscussionThe licensee identified this issue while reviewing a Westinghouse (W) document on RCP sealperformance during loss of RCP seal cooling events, OG-00-009, "Transmittal of RCP Operation During Loss of Seal Cooling (MUHP-1063)," dated February 11, 200 The Wdocument states that up to 21 gallons per minute (gpm) leakoff from each RCP could occur for loss of seal cooling events following postulated fire or Station Blackout (SBO) events, which exceeds the 3 gpm assumed in the Millstone Unit 3 fire safe shutdown analysi Therefore, the licensee concluded that the fire safe shutdown analysis was invalid, but the SBO analysis, which assumes 25 gpm leakoff, was valid.Upon further investigation, the licensee determined that a loss of seal cooling event could notbe mitigated successfully because the seal leakoff line could not be isolated by the air-operated valves (AOVs) located in the RCP seal return pipin These AOVs cannot be credited to close because they are not fed by a safety-related air system, and they are designed to fail ope As a result of the loss of seal cooling and fire scenarios described above, pressures in the seal leakoff line would reach approximately 800 to 2000 psi Since the piping segment downstream of each AOV and upstream of the flow restriction orifice is designed 150 psig, this portion of the leakoff line could rupture, inducing leakoff flow rates in excess of the 21 gpm identified in the W documen These flow rates severely challenge the credited contents of theBAST and the requirements for achieving and maintaining safe shutdown in accordance with the applicable licensing basis.The licensee had been aware of the potential for over pressurization of the seal leakoff linefrom a 1992 Westinghouse Technical Bulletin, NSD-TB-91-07-R1, "Over pressurization of RCP | | On January 13, 2003 the Millstone Unit 3 licensee identified that an over-pressurization of RCP |
| #1 Seal Leakoff Line." However, while the licensee had implemented specific recommendations contained in the bulletin, the licensee had not considered the potential for the AOVs in the seal leakoff line to be ope Therefore, the licensee did not consider a potential pressure boundary failure in the leakoff line that would divert the BAST contents credited for achieving and maintaining safe shutdown.To mitigate and resolve the events described in this IN the licensee has: (1) institutedcompensatory measures for the degraded condition, including continuous fire watches, placement of additional fire extinguishers in the three affected plant areas, and administratively controlling transient combustibles; (2) initiated plant design changes involving the RCP seal leak-off lines to preclude the possibility of rupture during loss-of-all-seal cooling events, i.e., | | |
| replacement of susceptible valves and flanges; (3) performed engineering analyses regarding the event's impact on charging pumps and pressurizer level during the event; and (4) revised fire shutdown strategies to effectively mitigate the even This information notice requires no specific action or written respons If you have anyquestions about the information in this notice, please contact one of the technical contacts listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager./RA/William D. Beckner, Chief Reactor Operations Branch Division of Inspection Program Management Office of Nuclear Reactor RegulationTechnical Contacts:Paul Cataldo, Region IWarren Lyon, NRR(860) 701-3470(301) 415-2897 E-mail: pcc1@nrc.govE-mail: wcl@nrc.govPhil Qualls, NRR(301) 415-1849 E-mail: pmq@nrc.gov | | seal leakoff lines could result from an extended loss of seal cooling following station blackout |
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| | (SBO) scenarios or postulated fires in specific plant areas coincident with a loss of offsite |
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| | power. Specifically, the licensee relies on operators to isolate the low pressure portion of the |
| | |
| | seal leakoff to prevent the line from over-pressurizing. The licensee determined this |
| | |
| | expectation may not be achievable because the valve used to isolate the low pressure portion |
| | |
| | of the seal leakoff line is an air-operated valve. This valve is designed to fail open upon loss of |
| | |
| | electrical power or instrument air, either of which could occur during a SBO or a loss of offsite |
| | |
| | power coincident with a postulated fire event. |
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| | The seal return line for RCPs is designed to recover leakoff volume, at low pressure and |
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| | temperature, and return it to the volume control tank or charging pump suction. In the event of |
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| | a fire in the cable spreading area, main control room, or instrument rack rooms, coincident with |
| | |
| | a loss of offsite power, a loss of RCP seal cooling could result. This situation can lead to a |
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| | significant increase in RCP seal leakage which would increase the pressure and fluid |
| | |
| | temperature in the seal return line. This over pressurization could result in a pressure boundary |
| | |
| | failure of the seal return line, further increasing the RCP seal leakage beyond that assumed in |
| | |
| | the safe shutdown analysis. |
| | |
| | The resulting rupture would divert more of the credited boric acid storage tank (BAST) volume |
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| | than was assumed in the development of the licensees fire safe-shutdown strategies. |
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| | Therefore, the strategies may not be adequate to achieve safe-shutdown. |
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| | Discussion |
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| | The licensee identified this issue while reviewing a Westinghouse (W) document on RCP seal |
| | |
| | performance during loss of RCP seal cooling events, OG-00-009, "Transmittal of RCP |
| | |
| | Operation During Loss of Seal Cooling (MUHP-1063)," dated February 11, 2000. The W |
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| | document states that up to 21 gallons per minute (gpm) leakoff from each RCP could occur for |
| | |
| | loss of seal cooling events following postulated fire or Station Blackout (SBO) events, which |
| | |
| | exceeds the 3 gpm assumed in the Millstone Unit 3 fire safe shutdown analysis. Therefore, the |
| | |
| | licensee concluded that the fire safe shutdown analysis was invalid, but the SBO analysis, which assumes 25 gpm leakoff, was valid. |
| | |
| | Upon further investigation, the licensee determined that a loss of seal cooling event could not |
| | |
| | be mitigated successfully because the seal leakoff line could not be isolated by the air-operated |
| | |
| | valves (AOVs) located in the RCP seal return piping. These AOVs cannot be credited to close |
| | |
| | because they are not fed by a safety-related air system, and they are designed to fail open. As |
| | |
| | a result of the loss of seal cooling and fire scenarios described above, pressures in the seal |
| | |
| | leakoff line would reach approximately 800 to 2000 psig. Since the piping segment |
| | |
| | downstream of each AOV and upstream of the flow restriction orifice is designed 150 psig, this |
| | |
| | portion of the leakoff line could rupture, inducing leakoff flow rates in excess of the 21 gpm |
| | |
| | identified in the W document. These flow rates severely challenge the credited contents of the |
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| | BAST and the requirements for achieving and maintaining safe shutdown in accordance with |
| | |
| | the applicable licensing basis. |
| | |
| | The licensee had been aware of the potential for over pressurization of the seal leakoff line |
| | |
| | from a 1992 Westinghouse Technical Bulletin, NSD-TB-91-07-R1, "Over pressurization of RCP |
| | |
| | #1 Seal Leakoff Line." However, while the licensee had implemented specific |
| | |
| | recommendations contained in the bulletin, the licensee had not considered the potential for the |
| | |
| | AOVs in the seal leakoff line to be open. Therefore, the licensee did not consider a potential |
| | |
| | pressure boundary failure in the leakoff line that would divert the BAST contents credited for |
| | |
| | achieving and maintaining safe shutdown. |
| | |
| | To mitigate and resolve the events described in this IN the licensee has: (1) instituted |
| | |
| | compensatory measures for the degraded condition, including continuous fire watches, placement of additional fire extinguishers in the three affected plant areas, and administratively |
| | |
| | controlling transient combustibles; (2) initiated plant design changes involving the RCP seal |
| | |
| | leak-off lines to preclude the possibility of rupture during loss-of-all-seal cooling events, i.e., |
| | replacement of susceptible valves and flanges; (3) performed engineering analyses regarding |
| | |
| | the event's impact on charging pumps and pressurizer level during the event; and (4) revised |
| | |
| | fire shutdown strategies to effectively mitigate the event. This information notice requires no specific action or written response. If you have any |
| | |
| | questions about the information in this notice, please contact one of the technical contacts |
| | |
| | listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager. |
| | |
| | /RA/ |
| | William D. Beckner, Chief |
| | |
| | Reactor Operations Branch |
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| | Division of Inspection Program Management |
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| | Office of Nuclear Reactor Regulation |
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| | Technical Contacts: Paul Cataldo, Region I Warren Lyon, NRR |
| | |
| | (860) 701-3470 (301) 415-2897 E-mail: pcc1@nrc.gov E-mail: wcl@nrc.gov |
| | |
| | Phil Qualls, NRR |
| | |
| | (301) 415-1849 E-mail: pmq@nrc.gov |
| | |
| | Attachment: List of Recently Issued NRC Information Notices |
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| | ML032760027 DOCUMENT NAME:C:\ORPCheckout\FileNET\ML032760027.wpd |
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| | See previous concurrence* |
| | OFFICE OES:RORP:DRIP Tech Editor RGN:I SPLB:DSSA |
| | |
| | NAME CPetrone* Pkleene* PCCataldo (per email) JHannon* |
| | DATE 06 /19 /2003 02 /24 /2003 07/14 /2003 09/30 /2003 OFFICE SRXB:DSSA SRXB:DSSA EMEB/DE SC:OES:DRIP PD:RORP:DRIP |
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| | NAME JUhle* JRWermiel* EImbro* TReis* ejb for WDBeckner |
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| | DATE 09/02/2003 09/05 /2003 06/20 /2003 10/02/2003 10/06/2003 |
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| | Attachment 1 LIST OF RECENTLY ISSUED |
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| | NRC INFORMATION NOTICES |
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| | _____________________________________________________________________________________ |
| | Information Date of |
| | |
| | Notice No. Subject Issuance Issued to |
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| | _____________________________________________________________________________________ |
| | 2003-18 General Electric Type SBM 09/26/2003 All holders of operating licenses |
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| | Control Switches With for nuclear power reactors, Defective Cam Followers except those who have |
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| | permanently ceased operations |
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| | and have certified that fuel has |
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| | been permanently removed from |
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| | the reactor vessel. |
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| | 2003-17 Reduced Service Life of 09/29/2003 All holders of operating licenses |
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| | Automatic Switch Company for nuclear power reactors. |
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| | (ASCO) Solenoid Valves With |
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| | Buna-N Material |
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| | 2003-16 Icing Conditions Between Pending All 10 CFR Part 72 licensees and |
| | |
| | Bottom of Dry Storage System certificate holders. |
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| | and Storage Pad |
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| | 2003-15 Importance of Followup 09/05/2003 All holders of operating licenses |
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| | Activities in Resolving for nuclear power reactors except |
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| | Maintenance Issues those who have permanently |
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| | ceased operation and have |
| | |
| | certified that fuel has been |
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| | permanently removed from the |
| | |
| | reactor vessel. |
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| | 2003-14 Potential Vulnerability of Plant 08/29/2003 All holders of operating licenses |
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| | Computer Network to Worm for nuclear power reactors, Infection except those who have |
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| | permanently ceased operations |
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| | and have certified that fuel has |
| | |
| | been permanently removed from |
| | |
| | the reactor vessel. |
| | |
| | Note: NRC generic communications may be received in electronic format shortly after they are |
| | |
| | issued by subscribing to the NRC listserver as follows: |
| | To subscribe send an e-mail to <listproc@nrc.gov >, no subject, and the following |
| | |
| | command in the message portion: |
| | subscribe gc-nrr firstname lastname |
|
| |
|
| ===Attachment:=== | | ______________________________________________________________________________________ |
| List of Recently Issued NRC Information Notices This information notice requires no specific action or written respons If you have anyquestions about the information in this notice, please contact one of the technical contacts listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager./RA/William D. Beckner, Chief Reactor Operations Branch Division of Inspection Program Management Office of Nuclear Reactor RegulationTechnical Contacts:Paul Cataldo, Region IWarren Lyon, NRR(860) 701-3470(301) 415-2897 E-mail: pcc1@nrc.govE-mail: wcl@nrc.govPhil Qualls, NRR(301) 415-1849 E-mail: pmq@nrc.gov
| | OL = Operating License |
|
| |
|
| ===Attachment:===
| | CP = Construction Permit}} |
| List of Recently Issued NRC Information NoticesDISTRIBUTION:IN FileADAMS ACCESSION NUMBER: ML032760027DOCUMENT NAME:C:\ORPCheckout\FileNET\ML032760027.wpdSee previous concurrence*OFFICEOES:RORP:DRIPTech EditorRGN:ISPLB:DSSANAMECPetrone*Pkleene*PCCataldo (per email)JHannon*DATE06 /19 /2003 02 /24 /2003 07/14 /200309/30 /2003OFFICESRXB:DSSASRXB:DSSAEMEB/DESC:OES:DRIPPD:RORP:DRIPNAMEJUhle*JRWermiel*EImbro*TReis* ejb forWDBecknerDATE09/02/2003 09/05 /200306/20 /200310/02/200310/06/2003OFFICIAL RECORD COPY
| |
| ______________________________________________________________________________________OL = Operating License CP = Construction PermitAttachment 1 LIST OF RECENTLY ISSUEDNRC INFORMATION NOTICES_____________________________________________________________________________________InformationDate of Notice N SubjectIssuanceIssued to_____________________________________________________________________________________2003-18General Electric Type SBMControl Switches With Defective Cam Followers 09/26/2003All holders of operating licensesfor nuclear power reactors, except those who have permanently ceased operations and have certified that fuel has been permanently removed from the reactor vessel.2003-17Reduced Service Life ofAutomatic Switch Company (ASCO) Solenoid Valves With Buna-N Material09/29/2003All holders of operating licensesfor nuclear power reactors.2003-16Icing Conditions BetweenBottom of Dry Storage System and Storage PadPendingAll 10 CFR Part 72 licensees andcertificate holders.2003-15Importance of FollowupActivities in Resolving Maintenance Issues09/05/2003All holders of operating licensesfor nuclear power reactors except those who have permanently ceased operation and have certified that fuel has been permanently removed from the reactor vessel.2003-14Potential Vulnerability of PlantComputer Network to Worm Infection08/29/2003All holders of operating licensesfor nuclear power reactors, except those who have permanently ceased operations and have certified that fuel has been permanently removed from the reactor vesse Note:NRC generic communications may be received in electronic format shortly after they areissued by subscribing to the NRC listserver as follows:To subscribe send an e-mail to <listproc@nrc.gov >, no subject, and the followingcommand in the message portion:subscribe gc-nrr firstname lastname}}
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| {{Information notice-Nav}} | | {{Information notice-Nav}} |
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Category:NRC Information Notice
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of Systematic Sample Plan for Operator Licensing Examinations1998-07-31031 July 1998 Development of Systematic Sample Plan for Operator Licensing Examinations 2016-04-27
[Table view] |
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, DC 20555-0001 October 6, 2003 NRC INFORMATION NOTICE 2003-19: UNANALYZED CONDITION OF REACTOR
COOLANT PUMP SEAL LEAKOFF LINE DURING
POSTULATED FIRE SCENARIOS OR STATION
BLACKOUT
Addressees
All holders of operating licenses or construction permits for pressurized water reactors (PWRs).
Purpose
The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice (IN) to alert
addressees to the recent identification of an unanalyzed condition involving the design of the
reactor coolant pump (RCP) seal leakoff line. The NRC anticipates that recipients will review
the information for applicability to their facilities and consider taking appropriate actions.
However, suggestions contained in this information notice are not NRC requirements; therefore, no specific action or written response is required.
Description of Circumstances
On January 13, 2003 the Millstone Unit 3 licensee identified that an over-pressurization of RCP
seal leakoff lines could result from an extended loss of seal cooling following station blackout
(SBO) scenarios or postulated fires in specific plant areas coincident with a loss of offsite
power. Specifically, the licensee relies on operators to isolate the low pressure portion of the
seal leakoff to prevent the line from over-pressurizing. The licensee determined this
expectation may not be achievable because the valve used to isolate the low pressure portion
of the seal leakoff line is an air-operated valve. This valve is designed to fail open upon loss of
electrical power or instrument air, either of which could occur during a SBO or a loss of offsite
power coincident with a postulated fire event.
The seal return line for RCPs is designed to recover leakoff volume, at low pressure and
temperature, and return it to the volume control tank or charging pump suction. In the event of
a fire in the cable spreading area, main control room, or instrument rack rooms, coincident with
a loss of offsite power, a loss of RCP seal cooling could result. This situation can lead to a
significant increase in RCP seal leakage which would increase the pressure and fluid
temperature in the seal return line. This over pressurization could result in a pressure boundary
failure of the seal return line, further increasing the RCP seal leakage beyond that assumed in
the safe shutdown analysis.
The resulting rupture would divert more of the credited boric acid storage tank (BAST) volume
than was assumed in the development of the licensees fire safe-shutdown strategies.
Therefore, the strategies may not be adequate to achieve safe-shutdown.
Discussion
The licensee identified this issue while reviewing a Westinghouse (W) document on RCP seal
performance during loss of RCP seal cooling events, OG-00-009, "Transmittal of RCP
Operation During Loss of Seal Cooling (MUHP-1063)," dated February 11, 2000. The W
document states that up to 21 gallons per minute (gpm) leakoff from each RCP could occur for
loss of seal cooling events following postulated fire or Station Blackout (SBO) events, which
exceeds the 3 gpm assumed in the Millstone Unit 3 fire safe shutdown analysis. Therefore, the
licensee concluded that the fire safe shutdown analysis was invalid, but the SBO analysis, which assumes 25 gpm leakoff, was valid.
Upon further investigation, the licensee determined that a loss of seal cooling event could not
be mitigated successfully because the seal leakoff line could not be isolated by the air-operated
valves (AOVs) located in the RCP seal return piping. These AOVs cannot be credited to close
because they are not fed by a safety-related air system, and they are designed to fail open. As
a result of the loss of seal cooling and fire scenarios described above, pressures in the seal
leakoff line would reach approximately 800 to 2000 psig. Since the piping segment
downstream of each AOV and upstream of the flow restriction orifice is designed 150 psig, this
portion of the leakoff line could rupture, inducing leakoff flow rates in excess of the 21 gpm
identified in the W document. These flow rates severely challenge the credited contents of the
BAST and the requirements for achieving and maintaining safe shutdown in accordance with
the applicable licensing basis.
The licensee had been aware of the potential for over pressurization of the seal leakoff line
from a 1992 Westinghouse Technical Bulletin, NSD-TB-91-07-R1, "Over pressurization of RCP
- 1 Seal Leakoff Line." However, while the licensee had implemented specific
recommendations contained in the bulletin, the licensee had not considered the potential for the
AOVs in the seal leakoff line to be open. Therefore, the licensee did not consider a potential
pressure boundary failure in the leakoff line that would divert the BAST contents credited for
achieving and maintaining safe shutdown.
To mitigate and resolve the events described in this IN the licensee has: (1) instituted
compensatory measures for the degraded condition, including continuous fire watches, placement of additional fire extinguishers in the three affected plant areas, and administratively
controlling transient combustibles; (2) initiated plant design changes involving the RCP seal
leak-off lines to preclude the possibility of rupture during loss-of-all-seal cooling events, i.e.,
replacement of susceptible valves and flanges; (3) performed engineering analyses regarding
the event's impact on charging pumps and pressurizer level during the event; and (4) revised
fire shutdown strategies to effectively mitigate the event. This information notice requires no specific action or written response. If you have any
questions about the information in this notice, please contact one of the technical contacts
listed below or the appropriate Office of Nuclear Reactor Regulation (NRR) project manager.
/RA/
William D. Beckner, Chief
Reactor Operations Branch
Division of Inspection Program Management
Office of Nuclear Reactor Regulation
Technical Contacts: Paul Cataldo, Region I Warren Lyon, NRR
(860) 701-3470 (301) 415-2897 E-mail: pcc1@nrc.gov E-mail: wcl@nrc.gov
Phil Qualls, NRR
(301) 415-1849 E-mail: pmq@nrc.gov
Attachment: List of Recently Issued NRC Information Notices
ML032760027 DOCUMENT NAME:C:\ORPCheckout\FileNET\ML032760027.wpd
See previous concurrence*
OFFICE OES:RORP:DRIP Tech Editor RGN:I SPLB:DSSA
NAME CPetrone* Pkleene* PCCataldo (per email) JHannon*
DATE 06 /19 /2003 02 /24 /2003 07/14 /2003 09/30 /2003 OFFICE SRXB:DSSA SRXB:DSSA EMEB/DE SC:OES:DRIP PD:RORP:DRIP
NAME JUhle* JRWermiel* EImbro* TReis* ejb for WDBeckner
DATE 09/02/2003 09/05 /2003 06/20 /2003 10/02/2003 10/06/2003
Attachment 1 LIST OF RECENTLY ISSUED
NRC INFORMATION NOTICES
_____________________________________________________________________________________
Information Date of
Notice No. Subject Issuance Issued to
_____________________________________________________________________________________
2003-18 General Electric Type SBM 09/26/2003 All holders of operating licenses
Control Switches With for nuclear power reactors, Defective Cam Followers except those who have
permanently ceased operations
and have certified that fuel has
been permanently removed from
the reactor vessel.
2003-17 Reduced Service Life of 09/29/2003 All holders of operating licenses
Automatic Switch Company for nuclear power reactors.
(ASCO) Solenoid Valves With
Buna-N Material
2003-16 Icing Conditions Between Pending All 10 CFR Part 72 licensees and
Bottom of Dry Storage System certificate holders.
and Storage Pad
2003-15 Importance of Followup 09/05/2003 All holders of operating licenses
Activities in Resolving for nuclear power reactors except
Maintenance Issues those who have permanently
ceased operation and have
certified that fuel has been
permanently removed from the
reactor vessel.
2003-14 Potential Vulnerability of Plant 08/29/2003 All holders of operating licenses
Computer Network to Worm for nuclear power reactors, Infection except those who have
permanently ceased operations
and have certified that fuel has
been permanently removed from
the reactor vessel.
Note: NRC generic communications may be received in electronic format shortly after they are
issued by subscribing to the NRC listserver as follows:
To subscribe send an e-mail to <listproc@nrc.gov >, no subject, and the following
command in the message portion:
subscribe gc-nrr firstname lastname
______________________________________________________________________________________
OL = Operating License
CP = Construction Permit
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list | - Information Notice 2003-01, Failure of a Boiling Water Reactor Target Rock Main Steam Safety/Relief Valve (15 January 2003, Topic: Uranium Hexafluoride)
- Information Notice 2003-02, Recent Experience with Reactor Coolant System Leakage & Boric Acid Corrosion (16 January 2003, Topic: Boric Acid, Weld Overlay)
- Information Notice 2003-03, Part 21 - Inadequately Staked Capscrew Renders Residual Heat Removal Pump Inoperable (27 January 2003, Topic: Boric Acid)
- Information Notice 2003-04, Summary of Fitness-For-Duty Program Performance Reports for Calendar Year 2000 (6 February 2003, Topic: Boric Acid, Fitness for Duty)
- Information Notice 2003-06, Failure of Safety-Related Linestarter Relays at San Onofre Nuclear Generating Station (19 June 2003)
- Information Notice 2003-08, Potential Flooding Through Unsealed Concrete Floor Cracks (25 June 2003)
- Information Notice 2003-09, Source Positioning Errors and System Malfunctions Administration of Intravascular Brachytherapy (16 July 2003, Topic: Brachytherapy, Uranium Hexafluoride)
- Information Notice 2003-11, Leakage Found on Bottom-Mounted Instrumentation Nozzles (8 January 2004, Topic: Unanalyzed Condition, Nondestructive Examination, Stress corrosion cracking, Eddy Current Testing)
- Information Notice 2003-12, Problems Involved In Monitoring Dose to Hands Resulting from Handling of Radiopharmaceuticals (22 August 2003, Topic: Uranium Hexafluoride, Power Uprate)
- Information Notice 2003-12, Problems Involved in Monitoring Dose to Hands Resulting from Handling of Radiopharmaceuticals (22 August 2003)
- Information Notice 2003-13, Steam Generator Tube Degradation at Diablo Canyon (28 August 2003)
- Information Notice 2003-14, Potential Vulnerability of Plant Computer Network to Worm Infection (29 August 2003)
- Information Notice 2003-15, Importance of Followup Activities in Resolving Maintenance Issues (5 September 2003)
- Information Notice 2003-17, Reduced Service Life of Automatic Switch Company (ASCO) Solenoid Valves With Buna-N Material (29 September 2003)
- Information Notice 2003-17, Reduced Service Life of Automatic Switch Company (Asco) Solenoid Valves with Buna-N Material (29 September 2003)
- Information Notice 2003-18, General Electric Type Sbm Control Switches with Defective Cam Followers (26 September 2003)
- Information Notice 2003-18, General Electric Type SBM Control Switches with Defective Cam Followers (26 September 2003)
- Information Notice 2003-19, Unanalyzed Condition of Reactor Coolant Pump Seal Leakoff Line During Postulated Fire Scenarios or Station Blackout (6 October 2003, Topic: Safe Shutdown, Unanalyzed Condition, Boric Acid)
- Information Notice 2003-20, Derating Whiting Cranes Purchased Before 1980 (22 October 2003, Topic: Unanalyzed Condition)
- Information Notice 2003-21, High-Dose-Rate-Remote-Afterloader Equipment Failure (24 November 2003, Topic: Unanalyzed Condition, Brachytherapy)
- Information Notice 2003-22, Heightened Awareness for Patients Containing Detectable Amounts of Radiation from Medical Administrations (9 December 2003, Topic: Unanalyzed Condition, Brachytherapy)
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