Letter Sequence Other |
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Results
Other: 05000346/LER-1984-009, :on 840616,during Conceptual Design Stage, Discovered That Unanalyzed Situation Existed in Auxiliary Feedwater Pump Rooms.Caused by High Energy Pipe Break. Hardware Mods Planned, 05000346/LER-1985-007, :on 850323,auxiliary Feedwater Pump Did Not Meet 40 Response Time Requirement.Caused by Rate at Which Turbine Accelerated to Full Speed of 3,600 Rpm.Internal Speed Setting Bushing Replaced, 05000346/LER-1985-011, :850602,during Testing,High Turbine Vibration Signal Tripped Turbine,Resulting in Reactor Trip.Caused by High Vibration Due to Reopening of Turbine Control Valve 3. Main Turbine Steam Valve Test Modified, ML19259C593, ML19259C595, ML20126B551, ML20132D113, ML20132D126, ML20132E594, ML20133B990, ML20133D356, ML20155C775
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MONTHYEARML19259C5951977-10-11011 October 1977
Supersedes Re Installation of Governor on Auxiliary Feed Pumps.Defect May Cause Governor to Bind, Preventing Turbine Reaching Design Speed
Project stage: Other
ML19259C5931977-11-14014 November 1977
Forwards Suppl to LER NP-32-77-16 to Provide Addl Info Re 770924 Primary Sys Depressurization & Release of Steam in Containment.Describes Multiple Failures of Equipment.Makeup Pumps Stabilized Primary Sys & Permitted Cold Shutdown
Project stage: Other
05000346/LER-1984-009, :on 840616,during Conceptual Design Stage, Discovered That Unanalyzed Situation Existed in Auxiliary Feedwater Pump Rooms.Caused by High Energy Pipe Break. Hardware Mods Planned1985-05-0707 May 1985
- on 840616,during Conceptual Design Stage, Discovered That Unanalyzed Situation Existed in Auxiliary Feedwater Pump Rooms.Caused by High Energy Pipe Break. Hardware Mods Planned
Project stage: Other
ML20126B5511985-06-10010 June 1985
Confirmatory Action Ltr Re 850609 Reactor Trip.Corrective Actions Listed,Including Reviews of MSIV Actuation & Auxiliary Feed Sys Actuation
Project stage: Other
ML20133B9901985-06-11011 June 1985
Sumbits Daily Highlight.On 850609,reactor Tripped When RCS Temp & Pressure Increased Due to Main Feedwater Pump 1 Trip. Sequence of Events Provided
Project stage: Other
ML20132D1261985-06-17017 June 1985
Expresses Concern Re 850609 Incident at Facility.Requests Briefing on 850621 to Subcommittee Re Facility Incident & Related Matters
Project stage: Other
ML20132D1131985-06-18018 June 1985
Forwards Chronology Re Third Diverse Powered Auxiliary Feedwater Pump,Per H Denton 850613 Request
Project stage: Other
ML20127N9021985-06-24024 June 1985
Summary of Operating Reactors Events Meeting 85-10 on 850612.Only 3 of 17 Items Scheduled for Completion by 850531 Remain Incomplete.List of Attendees,Summary of Events Discussed & Status of Previous Assignments Encl
Project stage: Meeting
05000346/LER-1985-007, :on 850323,auxiliary Feedwater Pump Did Not Meet 40 Response Time Requirement.Caused by Rate at Which Turbine Accelerated to Full Speed of 3,600 Rpm.Internal Speed Setting Bushing Replaced1985-06-27027 June 1985
- on 850323,auxiliary Feedwater Pump Did Not Meet 40 Response Time Requirement.Caused by Rate at Which Turbine Accelerated to Full Speed of 3,600 Rpm.Internal Speed Setting Bushing Replaced
Project stage: Other
ML20133D3561985-06-27027 June 1985
Forwards Questions Re Recent Incident at Facility.Expresses Interest in Steps to Be Taken Prior to Authorizing Restart. Requests Response within 10 Days or No Later than 850712
Project stage: Other
ML20155C7751985-07-0202 July 1985
Forwards Transcription of NRC Operations Ctr Recordings of Conversations of Headquarters Operations Officer W/Plant Personnel,Region III Staff & Emergency Officer Re 850609 Plant Incident
Project stage: Other
05000346/LER-1985-011, :850602,during Testing,High Turbine Vibration Signal Tripped Turbine,Resulting in Reactor Trip.Caused by High Vibration Due to Reopening of Turbine Control Valve 3. Main Turbine Steam Valve Test Modified1985-07-0202 July 1985
- 850602,during Testing,High Turbine Vibration Signal Tripped Turbine,Resulting in Reactor Trip.Caused by High Vibration Due to Reopening of Turbine Control Valve 3. Main Turbine Steam Valve Test Modified
Project stage: Other
ML20132E5941985-07-29029 July 1985
Part 21 & Deficiency Rept Re Torrey Pines Technology Limitorque motor-operated Valve Bypass Limit Switch Setting Procedure.Initially Reported in 850725 Telcon.Procedure Will Be Modified
Project stage: Other
1985-06-17
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CONFIRMATORY ACTION LETTER b rn 6 F
" June 10, 1985 Docket No. 50-346 Toledo Edison company ATTN: Mr. Richard P. Crouse Vice Asesident c
Nuclear Edison Plaza
-300 Madison Avenue Toledo, OH. 43652 Gentlemen:
This letter confirms the conversations on June 10, 1985, between you and Charles E. Norelius of my staff related to the reactor trip at the Davis-Besse Nuclear Plant on June 9, 1985.
While operating initially at 90% power, a reactor trip and other subsequent problems with the main and auxiliary feedwater systems resulted in a situation where no feedwater-flow was available for 10-12 minutes causing low level in the steam generators.
With regard to the matters discussed, we understand you have taken or will take the following actions:
1.
Hold in abeyance any work in progress (electrical or mechanical) and/or any work planned on equipment that malfunctioned during the incident, such as dismantling or disturbing existing evidence, until the NRC Investigative Team has had a opportunity to evaluate this event and concur on your proposed corrective action (s).
2.
Review main steam isolation valve actuation.
a.
Establish the cause(s) of the unexplained closure of both MSIVs.
b.
Determine and implement the corrective action (s)
~
necessary to prevent recurrence.
c.
Perform additional testing to ensure the MSIVs operate as required.
'3.
Review the auxiliary feed system actuation.
a.
Establish the cause(s) of the inadvertent trip of both auxiliary feedwater pumps (AFP).
b.
Determine and implement the corrective action (s) necessary to prevent recurrence.
CONFIRMATORY ACTION LETTER h
s 0 l
ZEc t
CONFIRMATORY ACTION LETTER D
Toledo Edison Company 2
June 10, 1985 4.
Review the main feed system operation.
a.
Establish the cause(s) of the inadvertent trip of the No. I main feed pump (MFP).
- b., Determine and implement corrective action (s) to prevent recurrence for both main-feed pumps.
5. --
Complete and submit to NRC Region III the results of your investigation of this event including your safety evaluation, an evaluation of thermal shock considerations for both Steam Generators (SG), the maximum S/G shell differential temperature, and possible general mechanical damage to any affected system (s).
Also report your basis for event classification and the adequacy of information as originally reported to the NRC on June 9, 1985.
6.
Complete the actions required by items 1-5 and obtain verbal concurrence from the NRC Region III Regional Administrator or his designee prior to authorizing restart (Mode 2) of the reactor.
7.
Main and Auxiliary Feed System Testing.
a.
Perform testing which can be performed below 5% power, of the MFP's to demonstrate all pumps operate as required.
b.
Perform testing of the AFP's to assure all pumps operate as required.
- c.
Appropriate test results, your conclusions, and a summary of corrective actions taken will be provided to the NRC resident office upon completion.
8.
After all actions required above are completed obtain verbal concurrence from the NRC Region III Regional Administrator or his designee prior to exceeding 5% reactor power.
CONFIRMATORY ACTION LETTER
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CONFIRMATORY ACTION LETTER RIII-CAL-85-06 a.
Toledo Edison Company 3
June 10, 1985 Please let us know immediately if your. understanding differs from that set
'forth above.
' Sincerely, Original signed by Jar:03 G. Keppler James G. Keppler Regional Administrator cc w/ enclosure:
S. Quennoz, Station Superintendent DMB/ Document Control Desk (RIDS)
Resident Inspector, RIII-Harold W. Kohn, Ohio EPA James W. Harris, State of Ohio Robert H.-Quillin,-Ohio
. Department of Health CONFIRMATORY ACTION LETTER RII RIII RII RI I RIII 5
ktfr Fo ney/kr buress Green b,
H rrison g
we s
g 06/10/85
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