IR 05000259/1974003
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RO Inspection Report No. 50-259/74-3 Licensee: Tennessee Valley Authority 818 Power Building Chattanooga, Tennessee 37301 Facility Name: Browns Ferry 1 Docket No.:
50-259 License No.:
DPR-33 Category:
B2 Location: Decatur, Alabama Type of License: 3293 Mwt, BWR (G-E)
Type of Inspection: Routine, Unannounced Dates of Inspection: February 28, March 12-15, and April 11-12, 1974 Dates of Previous Inspection: February 11-14, 1974 Principal Inspector:
W. S. Little, Reactor Inspector Facilities Test and Startup Branch Accompanying Inspector:
R. F. Sullivan, Reactor Inspector Facilities Operations Branch Principal Inspector: M 9/'/8-V W. S. Little, Reactor Inspector D6te
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Facilities Test and Startup Branch
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Reviewed By:
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R. C. Lewis,' Acting Chief-Date
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Facilities Test and Startup Branch 8604300218 860317
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R0 Rpt. No. 50-259/74-3-2-i l
SUMMARY OF FINDINGS I.
Enforcement Action A.
Violations 1.
Certain activities under your license appear to be in violation of AEC requirements. These apparent violations
are considered to be of Category II severity.
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a.
Contrary to the requirements of Section 3.3.B.3.d of the Technical Specifications, 'n two different occasions Tennessee Valley Authority (TVA) did not immediately shutdown the reactor when the rod sequence control system was not operable below 30% power.
(Details I, paragraph 6 and Details II, paragraph 15)
2.
Certain activities under your license appear to be in violation of AEC requirements. The following is considered to be of Category III severity.
a.
Contrary to the requirements of 10 CFR 50, Appendix B, Criterion XVII, TVA site procedures do not require QA documentation of the review and approval of the suitability of new material used in parts and components of critical safety systems.
(Details I, paragraph 2)
b.
Contrary to the requirements of Section 3.9.B.2 of the Technical Specifications, a diesel was taken out of service without performing the required testing.
(Details I, paragraph 6)
II.
Licensee Action on Previously Identified Enforcement Matters
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Violations 1.
Excessive Chlorine Concentrations in Sanitary Wastes Report 50-259/74-1, Violations I.A.l.c and I.A.l.d.
Resolved.
(Details I, paragraph 3)
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R0 Rpt. No. 50-259/74-3-3-2.
Failure to Record Water Quality Data Report 50-259/74-1, Violation I.A.2.a Resolved.
(Details I, paragraph 5)
3.
Failure to Keep Water Quality Records Report 50-259/74-1, Violation I.A.2.b.
Resolved.
(Details I, paragraph 4)
III. New Unresolved Items 74-3/1 Diesel Air Start Motor Failure (Abnormal Occurrence BFAO-7413)
TVA reported that during testing on February 25, 1974, the
left bank air starter failed to start the "A" diesel. This is the second recent failure of an air start motor due to rust in the air system.
(Details II, paragraph 13)
74-3/2 Failure of HPCI Following a Test (Abnormal Occurrence BFAO-7414)
On March 11, 1974, following a generator trip test the HPCI started properly, but then shutdown for an unknown reason. TVA will submit an abnormal occurrence report.
(Details II, paragraph 14)
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74-3/3 Failure of HPCI To Reach Rated Speed
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(Abnormal Occurrence BFA0-7416)
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On March 12, 1974, during a manual initiation test the HPCI pump failed to reach rated speed. TVA will submit
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an abnormal occurrence report.
(Details II, paragraph 16)
74-3/4 Vacuum Breaker Limit Switch Failure (Abnormal Occurrences BFAO-7417)
On March 15, 1974, during testing following the replacement of a limit switch on the drywell-to-suppression chamber vacuum breaker, the replacement switch failed to function properly. TVA will submit an abnormal occurrence report.
(Details II, paragraph 11 describes a recent similar failure)
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O RO Rpt. No. 50-259/74-3-4-74-3/5 Relief Valve Response Time Verification Awaiting documentation clarifying the response time verification.
(Summary,Section VII.D.)
IV.
Status of Previously Reported Unresolved Items 74-2/1 Turbine Building Vent Radiation Monitor (Abnormal Occurrence BFAO-748)
Closed.
(Details II, paragraph 8)
74-2/2 Main Steam Line Pressure Switch Setpoint Drift (Abnormal Occurrence BFAO-7410)
Awaiting results of accelerated testing and vendor's special study.
(Details II, paragraph 10)
74-2/3 Main Steam Relief Valve Stuck Open (Abnormal Occurrence BFAO-749)
A loose locking plate from the second stage piston shaf t prevented the valve from reseating. Modifications have been made to all main steam relief valves to correct the problem. This item is closed.
(Details II, paragraph 9)
74-1/1 Diesel Generator Voltage Regulator _ Failure (Abnormal Occurrence BFAO-7347)
Awaiting vendor's report.
(Details II, paragraph 2)
74-1/2 Main Steam Relief Valvo Bellows Seal Leakage (Abnormal Occurrence BFAO-7349)
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Valve has not yet been inspected.
(Details II, paragraph 3')
74-1/3 Drywell Isolation Valve Failure (Abnormal Occurrence BEAO-7351)
Closed.
(Details II, paragraph 4)
74-1/4 Low Pressure Coolant Injection (LPCI) Pressure Switch Setpoint Error (Abnormal Occurrence BFAO-7352)
Awaiting results of accelerated testing and vendor's special study.
(Details II, paragraph 5)
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i RO Rpt. No. 50-259/74-3-5-74-1/5 Reactor Water Level Switch Setpoint Drift (Abnormal Occurrence BFAO-741)
Awaiting results of accelerated testing and vendor's special study.
(Details II, paragraph 6)
74-16/8 Main Steamline Pressure Switch Setpoint Drift (Abnormal Occurrence BEAO-7344)
Switch was lost in transit to vendor. A trace for the missing package has been issued.
(Details II, paragraph 7)
l V.
Design Changes None VI.
Unusual Occurrences Main Steam Isolation Valve Closure Time (Abnormal Occurrence BFAO-7412)
The TVA report of the test results indicating that a valve had closed in 2.4 seconds rather than 3.5 seconds, was reviewed and the inspector had no further questions.
VII. Management Interview A.
The inspection results were discussed on March 15, 1974, with the following:
Tennessee Valley Authority (TVA)
Division of Power Production (DPP)
H. J. Green - Plant Superintendent
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J. W. Doty - Maintenance Engineer T. B. Lee - Maintenance Engineer A. M. Qualls - Assistant Operations Superintendent R. G. Metke - Plant Results Section Supervisor Division of Environmental Protection (DEP)
M. Lyon - Browns Ferry Health Physics Supervisor-
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R0 Rpt. No. 50-259/74-3-6-
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i Division of Construction (DEC)
E. Hilgeman - Administration M. N. Sawyer - Assistant Test and Startup Section Supervisor M. M. Price - Construction Engineer R. T. Hathcote - Project Manager Office of Power W. Poling - Quality Assurance Division of Power Resource Planning (DPRP)
R. L. Moore - Quality Assurance L. H.' Coots - Quality Assurance General Electric (G-E)
J. D. Martin - Operations Manager J. L. Penrault - Startup Test Engineer B.
QA/QC of Replacement Materials Violation I.A.2.a. w:s discussed. DPP individuals emphasized that the use of the ethylene-propytene 0-rings had been reviewed and approved following TVA's review of the Bergen-Patterson and G-E recommendations. The inspector emphasized that documentation confirming this had not been produced by TVA, and the DED memorandum transmitting the G-E recommendations did not state TVA's approval. On April 12, 1974, TVA did show the inspector documentation of their review and approval of the suitability of the new seal and 0-ring material. The inspector also questioned whether the existing Standard Practice _ Manuals,
properly implemented 10 CFR 50, Appendix B, Criterion III,
" Design Control," concerning the review and approval of the use of new materials in parts and components of critical safety systems. Page 80 of the Licensing Browns Ferry Safety Evaluation, dated June 26, 1972, requires the TVA quality control program to have procedures requiring the review and documentary approval of materials used in safety systems to determine their suitability.
(Details I, paragraph 2)
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RO Rpt. No. 50-259/74-3-7-j C.
Rod Sequence Control System (RSCS) Inoperability Violation I.A.1.a. was discussed. DPP stated that they did
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not think that they violated the Technical Specifications
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because:
1.
To move control rods in order to shutdown at less than
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30% power would also have been in violation of Technical Specifications.
2.
The operator did not move control rods at all until the RSCS was manually initiated which DPP believes was the safest action to take in this case.
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DPP had manually returned the RSCS to the operable j
condition within 40 minutes which in their interpretation
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was sufficiently responsive to the "immediate action"
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requirement of the Technical Specifications.
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The inspector replied that the Technical Specifications says that the reactor shall be brought to a shutdown condition immediately and the option of determining the reasons for I
the occurrence and possibly taking corrective action is not
allowed by the Technical Specifications. The inspector i
stressed the importance of strict compliance with the Technical j
Specifications, and that if TVA believes that the requirements are unnecessarily restrictive they can request Licensing's l
approval of the desired revisions, but prior to obtaining i
Licensing's approval they must comply with' the Technical Specifications as written.
(Details I, paragraph'6 and
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Details II, paragraph 15)
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D.
Relief Valve Response Time
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The inspector stated that his review of the certification records for the relief valves raised a question concerning the verification of the valve response time of 0.1 second.
TVA's construction / design deficiency report transmitted i
August 29, 1973, states that the valves were'successfully i
tested to meet a response time of 0.1 second. TVA pointed'
i out a signoff on the valve data sheets which indicated that
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the response and delay tiae were verified by tests. TVA
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R0 Rpt. No. 50-259/74-3-8-said that they recognized that the data sheets are not as specific on the response time as desirable, and they will obtain clarifying documentation to substantiate their position. The inspector said that this would be unresolved awaiting further information from TVA.
E.
HPCI Operating History The inspector expressed his concern over the large number of abnormal occurrences that have occurred related to the HPCI system. He stated that the frequency of problems could raise serious questions of system reliability. TVA replied that they were equally concerned, and were actively pursuing solutions to each problem.
F.
Operational Quality Assurance The inspector stated that TVA had had adequate time since the Orange Book was published to determine how they planned to j
respond to the new requirements described therein. The inspector asked TVA for a timetable stating when the appropriate action would be taken. TVA representatives said tnat TVA would meet the Orange Book requirements, but they could not commit to a timetable at that time. They promiaed to determine what they could do and to see if a timetable could be given.
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R0 Rpt. No. 50-259/74-3 I-1
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DETAILS I Prepared by:
W. ST Ufftle, Reactor Inspector
' D(te Facilities Test and Startup Branch Dates of Inspection: March 13-15 and April 11-12, 1974 Reviewed by:
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R. C. Lewis, Acting Chief
'Date Facilities Test and Startup Branch 1.
Persons Contacted Tennessee Valley Authority (TVA)
Division of Power Production (DPP)
H. J. Green - Plant Superintendent W. C. Thomison - 01emical Engineer T. B. Lee - Pkchanical Engineer J. F. Groves - Assistant Plant Superintendent Division of Construction (DEC)
R. T. Olson - Mechanical Engineer 2.
Bergen-Paterson Shock Suppressors The inspector questioned DEC and DPP personnel concerning the permanent recommended "fix" to the shock suppressors.
They stated that all Unit 1 Bergen-Paterson shock suppressors had been rebuilt during the December 1973, outage.
The inspector was shown the procedure followed in rebuilding the suppressors and the Parker Seal Company laboratory report support-ing the use of ethylene propylene seals and 0-rings in GE silicone fluid SF-il54.
None of the documentation confirmed TVA's approval of the use of the new material and a DPP individual could not find such documentation although he stated that several meetings had taken place within TVA to review and approve the use of the new seal material.
During the inspection of April 11-12, 1974, TVA showed the inspector the minutes of a meeting held on October 24, 1973, that did document TVA's revies and approval of the ethylene propylene material for 0-rings and seals.
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I RO Rpt. No. 50-259/74-3 I-2
i The Browns Ferry Safety Evaluation, June 26, 1972, page 80, stated
that the TVA quality control program should require appropriate records to substantiate the suitability of materials in systems
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important to safety. Further, it stated, in part, "... procedures require the cognizant design engineer to review vendor drawings including j
lists of materials to determine the suitability of materials used."
TVA DED procedure, TVA-QAP-II-1.3R1, " Control of Document Affecting Quality,"
May 10,1973, was revised to meet the Licensing requirements.
The inspector looked at standard practices BFA6, " Quality Control of Materials and Parts" and BEA28, " Plant Modifications After Issuance of Operating License and Before Commercial Operation," and neither of the
procedures clearly require the records to substantiate the suitability of new and different materials used for parts or components of critical
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safety systems.
It appears that the Browns Ferry quality control program does not meet Licensing's or 10 CFR 50, Appendix B, Criterion III re-quirements.
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3.
Excessive Chlorine Concentrations in Sanitary Waste, Report No.
50-259/74-1, Violations I.A.l.c. and I.A.1.d. and TVA letter of
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February 25, 1974.
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The inspector confirmed that the log sheets had been revised to high-light the column used for recording chlorine concentrations and to emphasize its license significance. The inspector stated that he had a
no further questions on this item.
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Failure to Keep Water Quality Data Records, Report No. 50-259/74-1, Violation I. A.2.b. and TVA letter of February 25, 1974.
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The inspector confirmed that log sheets had been revised emphasizing that they were permanent plant records. The inspector stated that he had no further questions on this item.
5.
Failure to Record Water Quality Data, Report No. 50-259/741,
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Violation I.A.2.a.
The requirement to record these data was in error. The Environmental Techt cal Specifications has been revised to remove dais requirement.
6.
Technic.1 Specifications t
On April 11, 1974, the inspector discussed the following with Browns Ferry management. The inspector expressed concern with TVA's action ta' ken during and following several incidents resulting in violations of Technical Specifications, which were reported as abnormal occurrences.
Twice recently, TVA reported that the RSCS became inoperable below f
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R0 Rpt. No. 50-259/74-3 I-3 30% power.
In the first instance, TVA did not immediately bring the reactor to a shutdown condition as stated in Technical Specification Section 3.3.3.3.d, but pronibited all control rod movements and took steps to make the RSCS operable before moving control rods. TVA's justification for this action was described in their ten-day Abnormal Occurrence Report BFAO-7415 dated March 22, 1974, and was that their action was safe. The inspector stated that the technical specifications do nct give them the options of complying with the stated requirements, or taking some other safe action. TVA replied that since "immediate" is defined in the technical specifications as ".... as soon as practic-able considering the safe operation of die unit and the importance of the required action" that this gives diem the option of taking action which they consider safe.
The inspector stated that the definition of "immediate" states that the ".... required action will be initiated as soon as pr.acticable...." and the required action is explicitly stated in the technical specifications as "....it shall be brought to a shutdown condition...". The inspector stated that the second instance of RSCS inoperability that resulted in an abnormal occurrence, supports i
his contention that not only is shutting the reactor down immediately required by the technical specifications, but appears to be safer than the action taken. TVA's ten-day Abnormal Occurrence Report BFAO-7420 dated April 4,1974, stated that the RSCS became inoperable below 30% power and again they did not immediately bring the plant to a shutdown condition, but took steps to prevent rod movement until the RSCS was made operable. However, it was subsequently found out by TVA that control rods had been inadvertently moved and the action taken which they thought inhibited the selection of all rods, in fact, had not done so.
If TVA had complied strictly with the technical specifications, they would not have unknowingly exposed themselves to a condition which was less safe than they believed it to be.
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The inspector stated his concern over Abnormal Occurrence Report BFAO-7419 dated March 29, 1973.
This described a technical specifi-cation violation in which the licensed operator authorized _taking
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a diesel out of service for testing without first demonstrating that the redundant diesels and the emergency core cooling systems were operable as required by the technical specifications.
The inspector discussed other occurrences which have resulted in technical specification violations during die past four months.
l He emphasized to TVA that:
(1) Strict adherence to technical specifications must be practiced.
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RO Rpt. No. 50-259/74-3 I-4 (2) If technical specifications are too restrictive, relief can only be obtained by requesting changes and revisions from Licensing.
(3) The licensed operator must not think dhat he has the option of doing anything other than what dae technical specifications require, even if he is convinced that other actions are safe.
TVA replied that it was their intention to adhere to technical specifi-cations and that they have taken steps to emphasize the importance of this to their operators. On April 12, 1974, a TVA representative told the inspector that orders had been issued to the licensed operators stating that if the RSCS becomes inoperable below 30% power that the reactor must be scrammed.
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R0 Rpt. No. 50-259/74-3 11-1 7n.
DETAILS II Prepared by: vi d n Wb 4 //V R. F. Sullivan, Reactor Inspector Date Facilities Operations Branch Dates of Inspection: February 28, 1974 and March 12-14, 1974 Reviewed by:
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C. M. Upright,ptg Chief
/ Dpfe Facilities Opc at e s Branch 1.
Individuals Contacted H. J. Green - Plant Superintendent J. F. Groves - Assistant Superintendent J. D. Glover - Shif t Engineer J. J. Erpenback - Nuclear Engineer T. B. Lee - Mechanical Engineer J. Tyg - Electrical Engineer 2.
Diesel Generator Voltage Regulator Failure (Abnormal Occurrence BFAO-7 347 )
The vendor had not yet reported on the cause of the failure. This item will remain open until the vendor's report is received.
3.
Main Steam Relief Valve Bellows Seal Leakage (Abnormal Occurrence BFAO-7349)
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The relief valve has been replaced but not yet inspected to determine cause of failure. This item will remain open until the inspection findings are examined.
4.
Drywell Isolation Valve Failure (Abnormal Occurrence BFAO-7351)
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The failed pilot solenoid which was removed was not saved for inspection nor could it be located during a special search for the failed valve.
The inspector again emphasized the importance of determining the cause for component failures. This item is considered closed.
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5.
Low Pressure Coolant Injection Pressure Switch Setpoint Error (Abnormal Occurrence BFAO-7352)
The special testing program for Barton Model 288 pressure switches is still in progress. TVA and GE representatives met with the vendor
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RO Rpt. No. 50-259/74-3 II-2 on March 6, 1974, to discuss the status of the test program and re-emphasize performance requirements. Some improvement in drift performance has been seen since the new type locking devices have been installed. This item remains open.
6.
Reactor Water Level Switch Malfunction (Abnormal Occurrence BFAO-741)
The switch involved is the Barton Model 288 as is the one above and is subject to the same special test program. This item remains open.
7.
Main Steamline High Flow Pressure Switch Setpoint Drif t (Abnormal Occurrence BFAO-7344)
The switch was shipped to the vendor for examination of the failed bellows; however, the package was apparently lost in transit. A trace has been placed in hopes of locating the package. This item remains open.
8.
Reactor and Turbine Building Ventilation Monitor Out of Service ( Abnormal Occurrence BFAO-748)
The inspector reviewed the ten-day report dated February 7,1974.
Retraining was conducted and tighter ' administrative controls were implemented to prevent recurrence. This item is considered closed.
9.
Main Steam Relief Valve Stuck Open (Abnormal Occurrence BFAO 749)
The inspector reviewed the ten-day report dated February 22, 1974.
The cause of the failure had not been determined by the date of report preparation, but more current information gained from valve disassembly
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and examination was given to the inspectors. We were also informed that an additional report would be submitted to Regulatory by TVA relating details of the valve malfunction and the corrective action taken.
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The relief valve which malfunctioned was disassembled and inspected and on February 22, 1974, the cause of the failure was determined.
The cause was attributed to a loose locking plate which came free from the nut on top of the second-stage piston shaft. The locking plate, which had been secured over the nut by a retaining wire inserted through a hole in the shaf t above the nut, worked past the wire and became lodged in the space above the shaf t.
Due to close clearances, this resulted in interference with piston movement so that it could not reseat.
In turn, thip prevented reseating of the primary piston so the relief valve could not close. General Electric and Target Rock were in consultation with TVA on the evaluation of the proble..
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RO Rpt. No. 50-259/74-3 II-3 The licensee decided to inspect the condition of the eleven installed relief valves and began shutdown of the reactor on the evening of Feb ruary 26, 1974, for this purpose.
Examination of all valves revealed no other instances of failed locking devices. Concern about the adequacy of the existing design of the locking device prompted action to design a new locking method and make the necessary modifications to the relief valves before resumption of reactor operation.
The new design required the drilling of a.063 inch diameter hole parallel to the axis of the shaft into the threaded section of both the shaft and the nut. A.062 inch diameter stainless steel wire was positioned in the hole to prevent rotation of the nut.
The top edge of the hole was upset to retain the wire in the hole.
A total of 22 valves were modified at the site with Target Rock and GE representatives present and three were shipped to Target Rock for modification.
The work at the site was performed according to written approved procedures. The procedures provided step-wise checklists, verification steps and acceptance testing.
The original job plan called for removal of the secondary and pilot stages as a sub-unit, the performance of the modification and the re-installation of the removed sub-uait to the main valve body.
Four of the eleven from Unit No. I were successfully modified following this plan. The other seven were found to have excessive leakage past the pilot valve when tested with nitrogen. This was corrected by lapping the pilot valve seat; however, since the pilot valve was disturbed, a recalibration of the reassembled relief valve using steam is required to certify it for reactor service. TVA does not currently have this test capability at the site but has plans to install a steam rig.
The seven affected relief valves were replaced with valves which had been modified and certifieu.
Performance of the relief valves which had been insta11ed'on Unit No.1 was verified on return to operations in accordance with Startup Test Instruction No. 26.
Each valve was test operated at 250 psig reactor pressure to confirm proper opening and reseating. Another :est cycle of each was conducted at operating pressure. A capacity test was also performed which showed a total flow of 9.069 x 106 lbs/hr as compared to the minimum design flow of 8.5 x 106 lbs/hr.
10. Main Steamline High Flow Switch Malfunction (Abnormal Occurrence BFAO-7410)
The inspector reviewed the ten-day report dated February 22, 1974, and discussed the incident with licensee personnel.
An accelerated
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RO Rpt. No. 50-259/74-3 II-4 testing program for these switches, Barton Model 278, has been initiated and a lower set point will be established to provide in-creased drift margin. The special testing program discussed in item 5 above is also applicable to this model Barton switch and the inspector will continue to follow the progress of that program. This item remains open.
11.
Suppression Chamber to Drywell Vacuum Breaker Check Light Failure ( Abnormal Occurrence BFAO-7411)
The inspector reviewed the ten-day report dated March 1,1974.
Since the report was written, personnel have had the oppertunity to enter the suppression chamber and inspect the circuit. The cause was determined to be a limit switch with a sluggish actuator which failed to provide indication of breaker valve closure. The limit switch was replaced. This item is considered closed.
12.
Main Steamline Isolation Valve Rapid Closure Time (Abnormal Occurrence BFAO-7412)
The inspector reviewed the ten-day report dated March 8,1974, and had further discussions with plant personnel. During a functional test of the main steam isolation valves, the measured closing time of one of the valves was outside the time frame stated in the technical specifications. Measured closing times were 2.4 and 2.5 seconds as compared to the technical specification of 3<T<5 seconds for operating time as shown in Table 3.7.A.
This apparent violation was reported as required by the license with the report including a description of the cause and corrective action. The inspector's review produced no additional information nor did any unanswered questions result.
13.
Diesel Generator Failure to Start with Lef t Bank of Starters (Abnormal Occurrence BFAO-7413)
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The inspector reviewed with operations personnel, the ten-day report dated March 7, 1974. The accelerated program for removing, cleaning and replacing starting motors on the diesel generators has been underway but not yet completed.
Some rust has been found in the motors which have been re-worked. TVA has increased the frequency for cleaning out the air lines to twice per month while the problem is still under study. The TVA design group has been, requested to perform a design review of the air system. This item will remain open.
14.
HPCI Shutdown For Unidentified Cause Following Generator Trip Test (Abnormal Occurrence BFAO-7414)
The inspector discussed the incident with operating personnel and also examined operating rccords. The incident occurred following a planned
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R0 Rpt. No. 50-259/74-3 II-5 generator load rejection test from 75% power on March 11, 1974. Systems appeared to operate as expected immediately following the generator trip and accompanying reactor scram.. The main steam isolation valves closed and the HPCI and RCIC systems both came into operation within 15 seconds following the trip. Some confusion exists as to why the HPCI and RCIC systems both shut off about 5 to 6 minutes later. The operator logged that they both tripped on turbine overspeed. A re-construction of events using chart recordings tended to support the conclusion that these two systems were shut down by high reactor water level. The evaluation was still in progress and this item will remain open.
15. Automatic Removal of the Rod Sequence Control System Below 30% Power (Abnormal Occurrence BFAO-7415)
During reactor startup on March 12, 1974, the rod sequence control system (RSCS) was removed from operation automatically at 26% power.
Technical Specification 3.3.B.3.a. requires that the RSCS be operable below 30% rated power. Technical Specification 3.3.B.3.d. further provides that the reactor shall be brought to a shutdown condition immediately if the above condition cannot be met.
Operating personnel continued reactor operation at steady power with no rod movements during a 40 minute period while the problem was being investigated and the RSCS was being returned to service. This item remains open until additional information is available.
16.
HPCI Failed to Reach Rated Speed During Test Operation (Abnormal Occurrence BFAO-7416)
On March 12, 1974, the HPCI failed to reach rated speed and flow during manual test operation of the system. The problem was tentatively attributed to a fault in the turbine control system. Investigation was underway. This item will remain open.
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