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Category:REPORTABLE OCCURRENCE REPORT (SEE ALSO AO
MONTHYEARML20024G4911972-04-25025 April 1972
Ro:On 720328,improper Fuctioning of RHR Svc Water Regulating Valve Control Occurred.On 720403,malfunction of Containment Isolation Valve Discovered.On 720403,HPCI Steamline High Area Temp Switch
1972-04-25
[Table view]
Category:LER)
MONTHYEARML20024G4911972-04-25025 April 1972
Ro:On 720328,improper Fuctioning of RHR Svc Water Regulating Valve Control Occurred.On 720403,malfunction of Containment Isolation Valve Discovered.On 720403,HPCI Steamline High Area Temp Switch
1972-04-25
[Table view]
Category:TEXT-SAFETY REPORT
MONTHYEARML20217D1261999-09-30030 September 1999
Monthly Operating Rept for Sept 1999 for Monticello Nuclear Generating Plant.With
ML20216E7031999-08-31031 August 1999
Monthly Operating Rept for Aug 1999 for Monticello Nuclear Generating Plant.With
ML20210Q0521999-08-0404 August 1999
Safety Evaluation Approving Relief Request 10 to License DPR-22 Per 10CFR50.55a(g)(6)(i).Inservice Exam for Relief Request 10,Parts A,B,C,D & E Impractical & Reasonable Assurance of Structural Integrity Provided
ML20210Q6611999-07-31031 July 1999
Monthly Operating Rept for July 1999 for Monticello Nuclear Generating Plant.With
ML20209F7901999-06-30030 June 1999
Monthly Operating Rept for June 1999 for Monticello Nuclear Generating Plant.With
ML20195H0351999-05-31031 May 1999
Monthly Operating Rept for May 1999 for Monticello Nuclear Generatintg Plant.With
ML20206N1721999-04-30030 April 1999
Monthly Operating Rept for Apr 1999 for Monticello Nuclear Generating Plant.With
ML20205N0861999-04-12012 April 1999
Safety Evaluation Re Licensee Response to GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power-Operated Gate Valves
ML20205P5701999-03-31031 March 1999
Monthly Operating Rept for Mar 1999 for Monticello Nuclear Generating Plant.With
ML20204H4951999-03-18018 March 1999
SER Concluding That Licensee Established Acceptable Program to Verify Periodically design-basis Capability of safety-related MOVs at Monticello.Therefore Staff Concludes Licensee Adequately Addressed Action Required in GL 96-05
ML20205G7391999-02-28028 February 1999
Monthly Operating Rept for Feb 1999 for Monticello Nuclear Generating Plant.With
ML20202F7901999-01-25025 January 1999
1999 Four Year Simulator Certification Rept for MNGP Simulation Facility
ML20199E4871999-01-0606 January 1999
SER Accepting Licensee 951116,960214 & 0524 Responses to NRC Bulletin 95-002, Unexpected Clogging of Residual Heat Removal Pump Strainer While Operating in Suppression Pool Cooling Mode
ML20199F6211998-12-31031 December 1998
Monthly Operating Rept for Dec 1998 for Mngp.With
ML20205H0561998-12-31031 December 1998
Northern States Power Co 1998 Annual Rept. with
ML20198P0691998-12-28028 December 1998
Safety Evaluation Concluding That NSP Proposed Alternative to Paragraph III-3411 of App III to 1986 Edition of Section XI of ASME Code Provides Acceptable Level of Quality & Safety.Alternative Authorized
ML20198D0751998-12-10010 December 1998
Safety Evaluation Supporting NSP Proposed Change to EOPs to Use 2/3 Core Height as Potential Entry Condition Into Containment Flooding
ML20198B2531998-11-30030 November 1998
Monthly Operating Rept for Nov 1998 for Monticello Nuclear Generating Plant.With
ML20195E3691998-11-12012 November 1998
Safety Evaluation Concluding That Licensee USI A-46 Implementation Has Met Purpose & Intent of Criteria in GIP-2 & Staff Sser 2 for Resolution of USI A-46
ML20195D2381998-10-31031 October 1998
Monthly Operating Rept for Oct 1998 for Monticello Nuclear Generating Plant.With
ML20198J4451998-10-22022 October 1998
Rev 2 to SIR-97-003, Review of Test Results of Two Surveillance Capsules & Recommendations for Matls Properties & Pressure-Temp Curves to Be Used for Monticello Rpv
ML20154L3471998-09-30030 September 1998
Monthly Operating Rept for Sept 1998 for Monticello Nuclear Generating Plant.With
ML20153F0511998-09-21021 September 1998
Rev 2 to MNGP Colr,Cycle 19
ML20153E9361998-09-0808 September 1998
Rev 1 to MNGP Colr,Cycle 19
ML20153B0861998-08-31031 August 1998
Monthly Operating Rept for Aug 1998 for Monticello Nuclear Generating Plant.With
ML20237B8461998-07-31031 July 1998
Monthly Operating Rept for July 1998 for Monticello Nuclear Generating Plant
ML20236W5041998-07-21021 July 1998
ISI Exam Summary Rept - Refueling Outage 19
ML20236R1941998-06-30030 June 1998
Monthly Operating Rept for June 1998 for Monticello Nuclear Generating Plant
ML20249A5861998-05-31031 May 1998
Monthly Operating Rept for May 1998 for Monticello Nuclear Generating Plant
ML20247K3971998-04-30030 April 1998
Monthly Operating Rept for Apr 1998 for Monticello Nuclear Generating Plant
ML20217D8731998-04-13013 April 1998
Rev 0 to MNGP Colr,Cycle 19
ML20217F6431998-03-31031 March 1998
Monthly Operating Rept for Mar 1998 for Monticello Nuclear Generating Plant
ML20216D1041998-03-0505 March 1998
Rev 21 to Operational QA Plan
ML20216H6481998-02-28028 February 1998
Monthly Operating Rept for Feb 1998 for Monticello Nuclear Generating Plant
ML20203G1431998-02-10010 February 1998
Rev 2 to Inservice Insp Exam Plan,Third Interval,920601- 020531
ML20203B2821998-01-31031 January 1998
Monthly Operating Rept for Jan 1998 for Monticello Nuclear Generating Station
ML20202F9161998-01-29029 January 1998
Special Rept:On 980128,two of Three Fire Protection Pumps Were Removed from Svc as Result of Sys Configuration Necessary to Support Planned Maintenance.Fire Pumps Were Returned to Svc on 980128
ML20216D2071997-12-31031 December 1997
1997 Annual Rept for Northern States Power Co
ML20197J8131997-12-31031 December 1997
Revised Evacuation Time Estimates for Plume Exposure Pathway Emergency Planning Zone at Monticello Nuclear Power Plant. W/One Oversize Drawing
ML20198P2201997-12-31031 December 1997
Monthly Operating Rept for Dec 1997 for Monticello Nuclear Generating Plant
ML20203J7131997-11-30030 November 1997
Monthly Operating Rept for Nov 1997 for Monticello Nuclear Generating Plant
ML20199G7051997-11-19019 November 1997
Safety Evaluation Authorizing Relief Request 8 of Third 10 Yr Inservice Insp Interval
ML20199H8181997-10-31031 October 1997
Monthly Operating Rept for Oct 1997 for Monticello Nuclear Generating Plant
ML20217K2081997-09-30030 September 1997
Monthly Operating Rept for Sept 1997 for Monticello Nuclear Generating Plant
ML20216H7771997-08-31031 August 1997
Monthly Operating Rept for Aug 1997 for Monticello Nuclear Generating Plant
ML20217K2741997-07-31031 July 1997
Monthly Operating Rept for Jul 1997 for Monticello Nuclear Generating Plant
ML20196H1081997-07-0808 July 1997
Rev 20 to Operational QA Plan
ML20141B9271997-06-30030 June 1997
LOCA Containment Analyses for Use in Evaluation of NPSH for RHR & Core Spray Pumps
ML20149E2921997-06-30030 June 1997
Monthly Operating Rept for June 1997 for MNGP
ML20148S6341997-06-23023 June 1997
NPSH - Rept of Sulzer Bingham Pump
1999-09-30
[Table view] |
Text
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!f .. L . -
NORTHERN STATES POWER COMPANY flinneapolis, Minnesota 55401 i
' , - .yx 'l -
L
, \ h '- ,j November 26, 1971
h i l EuI[h .
l G NOV2 91971 + '
u cu a, j Dr. Peter A. florris o
???M Division of Reactor Licensine 'O a
! United States Atomic Energy Commission Washington, D.C. 20545 ~ k'2.ifE$. ro
/
Dear Dr. f/crris:
fONTICELLO IOCLEAR GEIERATIIG PLANT Docket No. 50-263 Li cense No. DPR-22 Report on Win Steam Isolation Valve Problems Conditions have occurred recently at the Monticello IJuclear Generating Plant which we are reporting in accordance with the reporting reqJirements of seClion 6.6.B of the Technical Sp ecifications. T he Reg i on l i l "Compl i an ce o f fi ce has been noti fied of these events.
On November 13, 1971, an ISIV Closure Time Surveillance Test was conducted.
The closure tires for two of the eight LSIV's were not within the Technical Sp ecification limi ts of > 3 seconds and i5 seconds. ISIV 2-80B closed in 20 seconds and ISI V 2-860 closed in 1.2 seconds.
Investication revealed the fast closure of fSIV 2-86C (located outside of the primary coniainment)was caused by leakage from the oil dashpot cylinder external I piping. The dashpot piping and fittings on all ISIV's have been tightened, l sealed, or replaced to eliminate cil leakage. The oil level in the dashpois has l been checked and oil added as necessary, i Investigation revealed that ISIV 2-80B would close slowly only if it was opened and irnediately re-closed,, i f the valve was allowed to stay open for approximately {
one minute, its closure time was approximately 3.5 seconds which is within the i Technical $peci fication limi ts. Since this was the only ISIV which exhibited this ;
characteristic, the decision was made to de-inert the primary containment l (fSIV 2-80B is located inside the containment) and further investicate- this ;
p robl em. On November 15, 1971, ii was found that the main spool valve for ISIV l
2-80B was not operating ~ properly.
i The main spool valve was dis-assembled and it was found that the spool would !
not travel freely in the spool sleeve'. There was no evidence of any material on the spool. The spool was put on a lathe and an emery cloth was used to polish the spool piston. The main spool valve for fSIV 2-80B was exchanged with the test spool valve from ISIV 2-860 The troublesome spool valve was found to operate fy -
I 5201 91020S0452 711126 CF ADOCK 05000263 .
\ CF b. g. 1
<< .'a, * - -
properly when installed as the test spool val ve for LSIV 2-86C. LSI V 2-803 has been tested and found to operate properly.
On November 17 1971, while attempting to fill the reactor vessel with water to perform an opera,tional hydrostatic test on the primary system, i t was found that LSI V 2-86A was leaking. A local leek rate test was performed on November 18, 1971, by attempting to pressurize between the two mainsteam line A isolation valves 2-80A and 2-86A. The steamline could not be pressurized between the two valves indicatine that the isolation valve was leakinc greatly in excess of 11.5 SCFH as 1imitedb'y Techni cal Specifi cation 4.7. A.
~
On November 22,1971, LSI V 2-86A was dis-assembled and the seats were inspecied.
There were no indications on either the main seat or the pilot valve seat. On Novembe r 23, 1971, an inspection of the enti re valve assembly was performed and it was found that one of the three main poppet guides showed excessive wear on the lower 1 inch of cuide material. There was also indication on the side of the main poppet of wear between the guide and the poppet. I t is believed that the worn cuide allowed the main valve poppet to seat improperly resulting in the high leakare.
An Atwood and Morrill Company representative has been notified of the problem and will be on site durine the week of November 29 to assist with the invesiipation and corrective action! ~
A follow-up report will be prepared when our investigation is complete. The Region t il Compliance offi ce will be noti fied of any signi fi cant developments.
Yours very truly M
L.O. L,aye r 0 Di rector of Nuclear Support Services LOM/GHJ/caf I
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