IR 05000029/1989002
| ML20246N586 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 05/04/1989 |
| From: | Haverkamp D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20246N571 | List: |
| References | |
| 50-029-89-02, 50-29-89-2, NUDOCS 8905190478 | |
| Download: ML20246N586 (17) | |
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U.S. NUCLEAR REGULATORY COMMISSION Region I
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Report No.-
50-29/89-02-Docket No.:
50-29 License No.:
DPR-3 Licensee:
Yankee Atomic Electric Company 580 Main Street Bolton, Massachusetts 01740-1398 Facility Name: Yankee Nuclear Power Station Inspection at: Rowe, Massachusetts Inspection Conducted:
February 28
,ipril 10, 1989
. Inspectors:
John B. Macdonald, Senior Resident Inspector Michael T. Markley, Resident Inspector Dou las A. Dempsey, Reactor Engineer Approved By:
c/
h k / 4vec My"/cP9 DonaldR.Haverkamp,Chieff Date Reactor Projects Section No. 3C Inspection Summary-Inspection on Febraury 28 - April 10, 1989 (Report-No.
50-29/89-02)
Areas Inspected:
Routine inspection on daytime and back shifts (117 hours0.00135 days <br />0.0325 hours <br />1.934524e-4 weeks <br />4.45185e-5 months <br />) by two resident i n specto r.- of:
actions on previous inspection findings; opera-tional safety; security; plant operations; maintenance and surveillance; engineering support; radiological controls; licensee event reports; licensee response to NRC initiatives; and, periodic reports.
Results:
l 1.
General Conclusions on Adequacy, Strengths or Weaknesses in Licensee Program No unacceptable conditions were identified.
The April 6,1989 manual reactor scram (Section 6.1) was necessary as a result of personnel inat-tentiveness to procedural adherence during the performance of surveillance testing. The control room operator response to this event was appropriate and noteworthy.
However, the inspectors continue to review the circum-stances regarding the improperly conducted surveillance procedure (Section 7.1), as well as several potential weaknesses in the control of the reactor restart on April 7 (Section 6.2).
Nuclear instrumentation main-tenance prior to restart was well planned and coordinated (Sections 7.2 and 7.3).
8905190478 890504 I'
PDR ADDCK 05000029 '
O PNV
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Inspection Summary (Continued)
2.
Violations No violations were identified during this inspection period.
3.
Unresolved Items
's Two Unresolved Items were identified during this inspection period.
Review licensee resolution of several potential weaknesses associated
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with control of the April 7 reactor restart (50-29/89-02-01, Section 6.2).
Review licensee evaluation of the personnel error during performance
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of non-return valve logic testing and corrective actions to preclude recurrence (50-29/89-02-02, Section 7.1),
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TABLE OF CONTENTS Page 1.
Persons Contacted...........................................
2.
S umma ry o f Fac i l i ty Ac t i v i t i e s..............................
3.
Status of Previous Findings (IP 92701)*............
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3.1 (Closed) Violation 50-29/85-07-02:
Failure To Provide An Adequate Procedure for Conducting Technical Specification (TS) Required Surveillance of Meteorological Equipment.............................
L 3.2 (Closed) Follow Item 50-29/85-18-01:
Review Procedure Revisions to Incorporate Post-Maintenance Test Requirements.........................................
3.3 (Closed) Violation 50-29/86-02-01:
Failure to Provide An Adequate Procedure for Conducting TS required Surveillance of the Steam Generator Blowdown Monitoring Equipment........................-.........
3.4 (Closed) Unresolved Item 50-29/86-02-02:
Revise Procedure OP-4211, Emergency Feedwater System Operability Test to Incorporate Programmatic Controls for Use of Portable Test Equipment and Permanently Installed Instruments................................
3.5 (Closed) Unresolved Item 50-29/86-02-03:
Revise Procedures to Specify Calibrated Instrumentation Required..............................................
3.6 (Closed) Violation 50-29/86-08-01:
Failure to Satisfy TS Requirements for Main Coolant Loop Operability in Hot Standby.....................~..................
3.7 (Closed) Unresolved Item 50-29/87-02-01: TS Operability Requirements for Safety Injection Building Ventilation Fans PRV-1 and PRV-2............
4.
Operational Safety (IP 71707,71710)........................
4.1 Plant Operations Review................................
4.2 Safety System Review...................................
4.3 Inoperable Equipment...................................
4.4-Review of Temporary Change Requests and Mechanical Bypasses.............................................
4.5 Review of Switching and Tagging Operations.............
4.6 Operational Safety Findings............................
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Page 5.
Security (IP 71707).........................................
5.1 Observation s of Physical Security......................
6.
Plant Operations (IP 71707,71710,93702,82201,94703).....
6.1 Manual Reactor Trip Following Inadvertent Closure of a Non-Return Valve (NRV)..................
6.2 Reactor Restart Following Manual Scram.................
6.3 Engineered Safety Feature System Wal kdown..............
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7.
Maintenance / Surveillance (IP 71710,61726,62703,61700)....
7.1 Personnel Error During NRV Surveillance Testing........
7.2 Source Range Nuclear Instrumentation Inoperability.....
7.3 Intermediate Range Nuclear Instrument Inoperability....
7.4 Movable Incore Detector Sys tem Inoperability...........
8. ' Radiological Controls (IP 71707)............................
8.1 Observation of Radiological Protection and Controls....
8.2 Support of Incore Movable Detector System Maintenance.................
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9.
Licensee Event Reporting (LER)-(IP 90712,92700)............
9.1 Report Review Criteria.................................
-9.2 LER 88-15, Low-Pressure Safety Injection Pump Discharge Pressure Exceeds Technical S p ec i fi ca t i o n s.......................................
10.
Review of Licensee Response to NRC Initiatives (IP 92703),...............................................
10.1 Bypass of Non-essential Diesel Generator Trips (TI 87-07)...........................................
10.2 NRC Information Notice 89-33: Potential Failure t
of Steam Generator Tube Mechanical Plugs.............
11.
Review of Periodic and Special Reports (IP 90713)...........
12. Management Meetings (IP 30703,40700).......................
- The NRC Inspection Manual inspection procedure (IP) or temporary instruction (TI) that was used as inspection guidance is listed for each applicable report section.
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DETAILS 1.
Persons Contacted Yankee Nuclear power Station
- N. St. Laurent, Plant Superintendent
- T. Henderson, Assistant Plant Superintendent
- ~R. Mellor, Technical Director Yankee Atomic Electric Company (YAEC)
- B. Drawbridge, Vice President and Manager of Operations
- Attendees at exit interview on April 21, 1989.
The inspector also interviewed other licensee employees during the inspec-tion, including members of the operations, radiation protection, chem-istry, instrument and control, maintenance, reactor engineering, security, training, technical services and general office staffs.
2.
Summary of Facility Activities Yankee Nuclear Power Station (Yankee, YNPS or the plant) remained at 100%
power until March 21, 1989, when a preplanned power reduction to approxi-mately 80% power was performed in order to facilitate heater drain pump ma:ntenance.
The No. I heater drain pump was replaced and full power operations were resumed on March 21, 1989. On April 6, a manual reactor scram was initiated in accordance with plant procedures following the inadvertent closure of a non-return valve during surveillance testing.
Requisite restart actions were completed and the reactor was made critical on April 7.
Full power was attained the morning of April 9.
The Institute of Nuclear Power Operations conducted an onsite periodic appraisal and evaluation of licensee activities on March 13-24.
Two Region I specialist inspections were conducted during April 3-7; one was a routine physical security inspection (Inspection Report 50-29/
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89-04) and the other was an inspection of the status of Generic Letter
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83-28 action item completion (Inspection Report 50-29/89-05).
l Mr. John B. Macdonaid was assigned as Senior Resii nt Inspector at Yankee effective March 12.
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3.
Status of Previous Inspection Findings j
t 3.1 (Closed)
Violation 50-29/85-07-02:
Failure to Provide an Adequate
Procedure for Conducting Technical Specification (TS) Required
,' surveillance of Meteorological Cquipment.
On April 24, 1985, the
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inspector identified that the licensee had failed to establish writ-ten procedures that would prescribe the qualitative assessment of instrument channel behavior that would ascertain the daily operabil-ity of the meteorological monitoring instrument channels. This qual-itative assessment is explicit in the TS definition of an instrument channel check.
Failure to provide written guidance resulted in log-i ging as operable a meteorological instrument which in fact was
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The inspector reviewed administrative procedure AP-2007, Revision 30, " Maintenance of Operations Department Logs," dated January 1989, and the licensee response (FYR 85-74 dated July 8, 1985)
to the Notice of Violation and determined that the licensee correc-tive actions to the violation were adequate to prevent recurrence.
This item is closed.
3.2 (Closed) Follow Item 50-29/85-18-01:
Review Procedure Revisions to Incorporate Post-Maintenance Test Requirement.
As a result of dis-cussions with the inspector regarding performance of surveillance procedure OP-4525, Revision 6, " Surveillance Inspection of Rod Drive ACBs", the licensee modified the procedure to require a post-mainten-ance response time test and to provide a standard method of inducing the test voltage required to test the breaker shunt trip coils. The
inspector verified that the changes had been appropriately incor-porated into OP-4525. This item is closed.
3.3 (Closed)
Violation 50-29/86-02-01:
Failure to Provide an Adequate Procedure for Conducting TS Required Surveillance of the Steam Generator Blowdown Monitoring Equipment.
On January 8, 1986, the inspector determined that the licensee had been unable to verify the l
operability of the No. 4 steam generator blowdown radiation monitor during channel checks.
Failure of procedures to provide qualitative criteria sufficient to ensure the proper performance of operability j
channel checks resulted in a similar violation in 1985 (50-29/
l 85-07-02, refer to Section 3.1).
In response (FYR 86-043 dated April 23, 1986) to this Notice of Violation, the licensee committed to review instrumentation requiring qualitative assessment per TS to ascertain if further procedural guidance was required. After review-ing Administrative Procedure AP-2007, Revision 30, " Maintenance of Operations Department Logs," dated January 1989, the inspector con-cluded that sufficient guidance existed to assure the qualitative operability assessment of all affected instrument channels.
This item is closed.
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3.4 (Closed)
Unresolved Item 50-29/86-02-02:
Revise Procedure OP-4211, Emergency Feedwater System Operability Test, to Incorporate Program-I matic Controls for Use of Portable Test Equipment and Permanently i
Installed Instruments.
The inspector reviewed this surveillance-
procedure and determined that all calibrated portable test eqdipment
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and permanently installed instrumentation used to record data were identified and documented in accordance with applicable - ANSI stand-ards, the licensee quality assurance program. manual, and station administrative procedures. This item is closed.
3.5 (Closed) Unresolved Item 50-29/86-02-03: Revise Procedures to Specify Calibrated Instrumentation Required.
This item expanded the scope of Unresolved Item 50-29/86-02-02 to include licensee management review of all procedures governing QA activities.
The inspector verified that calibrated instrumentation required to perform surveillance testing was specified by reviewing a representative sample of sur-veillance procedures. No inadequacies were identified. This item is closed.
3.6-(Closed)
Violation 50-29/86-08-01:
Failure to Satisfy TS Require-ments for Main Coolan; Loop Operability in Hot Standby.
This viola-i tion involved the improper opening of. main coolant system loop bypass valves while in hot standby; failure to perform the valve surveil-lance required by TS, and failure to establish a procedure to ensure the performance of the required surveillance test.
Following review i
of the corrective actions taken by the licensee in response to the Nutice of Violation, the inspector determined that the appropriate corrective measures had been implemented by station management. This item is closed.
3.7 (Closed) Unresolved Item 50-29/87-02-01: TS Operability Requirements
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'for Safety Injection Building Ventilation Fans PRV-1 and PRV-2.
Though not explicitly recognized in TS these safety class fans are considered a subsystem of the emergency core cooling system (ECCS).
At least one fan must operate when ECCS is operating in the sump recirculation mode and outside ambient temperature is greater than 40 degrees Fahrenheit.
On April 6,1987, the inspector concluded that
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the guidance available to aid operators in determining the TS opers-bility requirements of PRV-1 and PRV-2 was inadequate.
In response to the inspector concern, on April 8, 1987, the licensee issued
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Special Order No. 87-30 to provide interim guidance to operators. On March 15, 1988, TS Interpretation No. 88-2 was issued incorporating l
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the guidance provided in the special order.
This item is closed.
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4.
Operational Safety l
4.1 Plant Operations Review
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The inspector observed plant operations during regular and backshift tours of the following areas:
Control Room Safe Shutdown System Building Primary Auxiliary Building Cable Tray House Diesel Generator Cubicles Fence Line (Protected Area)
Vital Switchgear Room Intake Structure Turbine Building Spent Fuel Pit Building Control room instruments were observed for correlation between chan-nels, proper functioning, and conformance with technical specifica-tions. Alarm conditions in effect and alarms received in the control room were reviewed and discussed with the operators. Operator aware-ness and response to these conditions were reviewed. Operators were found cognizant of board and plant conditions.
Control room and shift manning were compared with technical specification require-ments. Posting and control of radiation, contaminated and high radi-ation areas were inspected. The use of and compliance with radiation work permits and use of required personnel monitoring devices were checked.
Plant housekeeping controls were observed including control of flammable and other hazardous materials. During plant tours, logs and records were reviewed to ensure compliance with station proced-ures, to determine if eatries were correctly made, and to verify cor-rect communication of equipment status.
These records included various operating logs, turnover sheets, tagout and jumper logs, and event deportability evaluation requests and logs. Inspections of the control room were performed on backshifts including March 7-9, 13-15, 20-24 and 27-30.
Operators and shift supervisors were alert, atten-tive and responded appropriately to annunciators and plant conditions.
4.2 Safety System Review The emergency diesel generators (EDG), EDG fuel oil, containment isolation and high pressure and low pressure safety injection systems were reviewed to. verify proper alignment and operational status in the standby mode. The review included verification that (1) access-ible major flow path valves were correctly positioned, (ii) power supplies were energized, (iii) lubrication and component cooling was proper, and (iv) components were operable based on a visual inspec-
tion of equipment for leakage and general conditions.
No violations or safety concerns were identified.
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4.3 Inoperable Equipment j
i Actions taken by plant personnel during periods when equipment was inoperable were reviewed to verify that:
technical specification limits were met; post-maintenance testing was completed satisfac-torily; and, equipment was properly returned to service upon comple-tion of repairs.
This review was completed for the following items:
March 16-April 6 Excore nuclear instrumentation source
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range channel 2 was declared inoperable due to erratic response during surveillance testing.
' Refer to Section 7.2 for more detail (MR 89-0741).
March 16-April 7
-- Excore nuclear instrumentation intermedi-
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ate range channel 3 was declared inoperable due to inadequate gain response during sur-veillance testing. Refer to Section 7.3 for more detail (MR 89-0744).
March 13-April 6
-- Incore nuclear instrumentation paths C4
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and G3 were declared inoperable due to flow-path restrictions.
Refer to Sections 7.4 and 8.2 for more detail.
4.4 Review of Temporary Change Requests and Mechanical Bypasses Temporary Change Requests (TCRs), which include lifted leads and l
jumpers and mechanical bypasses, were reviewed to verify that con-trols established by AP 0018, " Temporary Change Controi," were met, no conflicts with the technical specifications were created, the requests were properly approved prior to installation, and a safety evaluation in accordance with 10 CFR 50.59 was prepared if required.
Implementation of the requests was reviewed on a sampling basis. The following requests were reviewed:
TCR 89-139 -- implemented and restored on April 6, 1989, to sup-
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port maintenance performed on source range nuclear instrument channel 2.
TCR 89-140 -- implemented April 6 and restored April 7, to sup-
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port maintenance performed on intermediate range nuclear instru-ment channel 3.
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6 4.5 Review of Switching & Tagging Operations
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The switching and tagging log was reviewed and tagging activities
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were inspected to veri fy that plant equipment was controlled in accordance with the requirements of AP 0017, " Switching and Tagging of Plant Equipment." The following switching and tagging order was reviewed:
89-332 -- issued and restored on March 9 to isolate an elec-
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trical ground located in the gate house unit heater circuitry.
4.6 Operational Safety Findings Licensee administrative control of off-normal system configurations by the use of the TCR mechanical bypass, and switching and tagging procedures, as reviewed in Sections 4.4 and 4.5, was in compliance with procedural instructions and was consistent with plant safety.
Licensee efforts to minimize active lifted leads, jumpers and mechanical bypasses is noteworthy.
5.
Security 5.1 Observations of Physical Security Selected aspects of plant physical security were reviewed during regular and backshift hours to verify that controls were in accord-ance with the security plan and approved procedures.
This review i
included the following security measures:
guard staffing; vital and protected area barrier integrity; maintenance of isolation zones; and, implementation of access controls, including authorization, i
badging, escorting, and searches.
No inadequacies were identified.
6.
Plant Operations 6.1 Manual Reactor Trip Following Inadvertent Closure of a Non-Return Valve On April 6, at 11:23 a.m., the reactor was manually scrammed from l
100% of rated power following the inadvertent closure of the No. 1 l
non-return valve (NRV) during surveillance testing (see Section 7.1
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for more detail).
Closure of the No. 1 NRV caused a pressure increase and resultant level shrink in the No. 1 steam generator.
Low steam generator level alarm annunciation was the first indication the operators received that a transient condition existed.
Upon recognition that an NRV had closed, the shift supervisor immediately l
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L directed the operators to manually scram the reactor in accordance L
with OP-3204, " Inadvertent Closure of a Non-Return Valve "
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reactor was - quickly stabilized in Mode 3.
All plant equipment per-
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The No. 2 EDG. automatically. started when the main generator was secured and power to bus No. I was lost. Bus No.
i 1 was. subsequently cross-tied to bus No. 3 and the No. 2 EDG was
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secured.
The response of the operators to this transient was noteworthy..The closing NRV was quickly identified, the reactor was promptly manually scrammed and the NRV was re-opened before the affected No. I steam-line safety relief valve actuated.
The inspectors had no further questions with regard to operator actions'during this event.
6.2 R_eactor Restart Following Manual Scram The post-trip report was reviewed by the Plant Operations Review Committee (PORC) on April 6.
Concurrence to restart was provided when nuclear instrumentation channels No. 2 'and No. 3 were returned to service, At 7:34 a.m. on April 7, the reactor was made critical-and entered Mode 2 (startup). The generator was phased to the grid (entered Mode 1) at 12:22 p.m. the same day. The plant achieved 100%
of rated power operation at 6:00 a.m. on April 9.
Inspector review of. the startup indicated some questionable condi-tions existed regarding the critical approach and the ' associated estimated critical position (ECP). determination.
Specifically, reactor criticality was achieved at a significantly lower control rod bank position than the calculated ECP.
The operations shift super-visor (SS) and shift technical ' advisor (STA) reviewed the ECP calcu-lation relative to the critical approach 1/M plot data. The licensee did not identify an ECP anomaly, but decided to proceed with the critical approach based on 1/M plot data and on the assumption that the error was due to xenon burnup. Subsequent review by the reactor engineering staff determined that an ECP calculational error had been made. The revised calculation was in close agreement with the crit-ical approach 1/M plot.
The inspector expressed concern that the decision to continue rod withdrawal was made when the observed point of criticality was below the calculated minimum control rod position reactivity toleronce and
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that the cause of the discrepancy was erroneously assumed.
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tional inspector concerns include the adequacy of ECP review, control room protocol, and the timeliness of input data (such as Baron con-centration) for the reactivity calculations.
Cognizant personnel indicated that an excessive number of personnel were in the control room during the startup evolution.
The licensee acknowledged the inspector concerns and is evaluating the reso1Ltion of the weaknesses
observed during startup.
This item is unresolved (50-29/89-02-01).
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r ' e-6.3 Engineered Safety Feature, System Walkdown
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The inspectors performed a comprehensive walkdown of all acchssibla portions of the high and low safety pressure injection systestsw The inspectors observed excellent equipment material condition 'ahd4trea cleanliness.
Proper system alignment and. component' labeling were verified.
Power supply and breaker alignment was verified. Hangers and supports were properly made up and aligned. Instrumentation cal-ibration data were up to date and indicated proper calibration periodicities.
Drawings and procedures were verified to accurately reflect as-built conditions.
The inspectors noted a lack of consis-tent control of pipe ' caps and plugs on test connections and vent paths.. Generally, caps and plugs were found to be present when not identified on drawings or procedures.
This observation did not impact system operability or containment penetration boundary integ-rity and was brought to the attention of the licensee for resolution.
The inspectors had no further questions.
7.
Maintenance / Surveillance 7.1 Personnel Error During NRV hrveillance Testing On April 6, during functional testing of the NRV control system logic, an I&C technician failed to perform a restorative procedural step which resulted in the inadvertent ' closure of the No. 1'NRV.
Upon receipt of the NRV closure, the control -room operators manually scrammed the reactor in accordance with plant procedures (see Section 6.1 for more detail).
Procedure OP-4661, " Functional Test of. - the Non-Return Valve Automatic Control System," Revision 7, steps 2.a-2.h require the NRV control switches to be placed from the normal "AUT0" position to the test "0 PEN" position and direct the I&C technician to input various test signals which simulate NRV trip and trouble signals and verify logic system operability. The actions of step 2.1 clear NRV trip signals -and de-energize the Train A reactor trip auxiliary relay, K53A, prior to the performance of step 2.k which returns the NRV control switch to the "AUT0" position.
While per-forming this portion of the procedure for
.e No.1 NPN Train A logic the technician failed to perform step 2.1.
When the No. 1 NRV con-trol switch, CS-1A,
,,as returned to the "AUT0" position, the K53A relay, which remained energized, caused the No. 1 NRV to close.
Fol-lowing receipt of steam generator low level alarms, the technician recognized the error and informed the control room operators that the No. 1 NRV had been inadvertently closed. The reactor was promptly manually scrammed and the NRV was reopened.
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This event-appears 'to have' been an isolated -instance of individual
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inattentiveness to procedural adherence and not indicative of.declin-ing performance in the surveillance test program.
However, the inspectors will continue to review this' event and subsequent licensee corrective actions to preclude recurrence.
The failure tot follow approved plant procedures is identified as an unresolved item pending completion of the above review (50-29/89-02-02).
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7.2 Source Range Nuclear Instrumentation Inoperability-On March 16, during nuclear instrumentation (NI) channel functional testing, the channel 2 source range NI.provided erratic indication and was declared inoperable. The TS allow indefinite continued power operation with an inoperable source range channel. However, prior to reactor restart following the April 6 reactor scram, the channel was required to be operable.
Troubleshooting and corrective maintenance was pe'rformed by I&C and was documented in MR 89-0741.. The instru-ment drawer was removed ~ and the selector switch was dissembled and cleaned with alcohol and freon and reassembled.
The log micro-ammeter drawer was reinstalled and was allowed to warm to normal temperature. The channel was functionally tested satisfactorily and -
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returned to service later on April 6.
The inspectors had no further questions regarding this activity.
7.3 Intermediate Range Nuclear Instrumentation Inoperability The channel 3 intermediate range NI was also declared inoperable on March 16 following unsatisfactory response during functicnal testing.
The TS allow indefinite continued power operation with or,e intermedi-ate range NI inoperable and all power range instrumentation operable.
. llowever, prior to restart following the April 6 reactor scram this channel was required to be operable.
Troubleshooting revealed a faulted micro-ammeter drawer, which was subsequently. replaced as documented in MR 89-744.
Following a temperature soak, the channel was functionally tested satisfactorily and returned to service on April 7.
The inspectors had no further questions regarding this activity.
The licensee expeditiously completed the NI corrective maintenance minimizing the impact on unit availability.
This effort was the result ' of proper maintenance preplanning and coordination with the operations department. No inadequacies were identified.
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-7.4 Movable Incore Detector System Inoperability
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During performance of OP-7105, " Normal Operation of the Flux Rapping System," Revision.12, on March 13-20, 1989, the licensee experienced difficulty in completing the ir. core flux run. Specifically,. detector and flowpath operability problems occurred.
Both the
"A" and
"B" detectors experienced flowpt.th restriction in rath C4. Detector "B" became stuck in flowpath G3 for approximately 2.5 days.
It was manually freed and moved to the upper core region' to decay.
It was subsequently moved to storage for future inspection. :Incore flow-paths C4 and G3 were declared inoperable and the incore flux run was completed with the replaced
"A" detector.
The licensee plans to evaluate the flowpath restrictions and detector sticking during the next refueling outage.
Additional licensee corrective action. may include increased use of fixed incore detectors.
The licensee demonstrated sound technical judgment in resolving immediate operability and surveillance needs.
Power distribution surveillance requirements were satisfied with the successful comple-
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tion of the incore flux run.
The TS requirements for minimum flow-path operability were maintained.
No compromise of' reactor coolant system integrity occurred. A conservative attitude was demonstrated.
in performing corrective maintenance and radiological safety as described in Section 8.2 of this report.
8.
Radiological Controls 8.1 Observation of Radiological Protection and Controls Radiological controls were reviewed on - a routine basis relative to industry radiological standards, administrative and radiological con-trol procedures, and regulatory requirements.
Selected work evolu-tions were observed to determine the adequacy of program implementa-tion commensurate with the radiological hazards and importance to safety.
Independent surveys were performed by the inspector to verify the adequacy of radiological controls and instructions to
workers.
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8.2 Support of Incore Movable Detector System Maintenance Inspector review of radiological controls for maintenance on the movable incore detector system indicated good performance.
The licensee was effective in analyzing the radiological hazards and I
implementing controls to maintain exposures as IN as reasonably achievable.
Specifically, the "B" movable incore detector had become stuck in the active region of the core for approximately 2.5 days.
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The licensee calculated dose rate, if withdrawn without decay, was 1333 Rem / hour at eighteen inches from the fission detector.
Effec-i tive planning and implementation enabled the licensee to manually 1;
free the detector, provide decay in the upper head region, and even-l tually store the detector in the appropriate shielding container.
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The licensee plans to replace the detector after sufficient. decay
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time has elapsed.
The licensee continues to demonstrate. sod per-l formance for evolutions where significant potential for high person-nel exposure exists.
For this evolution, the highest individual exposure was 15 mrem and the collective exposure.was 50 mrem.
Inspector review noted that radiation work permits (RWPs) and radio-
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logical surveys provide adequate worker guidance. Most RWPs were for general plant activities.
Radiological posting and labeling were consistent with administrative and regulatory requirements.
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9.
Licensee Event Reporting (LER)
9.1 Report Review Criteria The inspector reviewed the below listed licensee event report (LER)
to determine that with respect to the general aspects of the event:
(1) the report was submitted in a timely manner; (2) description of the event was accurate; (3) root cause analysis was performed; (4) safety implications were considered; and (5) corrective actions i
implemented or planned were sufficient to preclude recurrence of a similar event.
9,2 LER 88-15 - Low Pressure Safety Injection Pump Discharge Pressure Exceeds Technical Specifications The LER 88-15, " Low Pressure Safety Injection Pump Discharge Pressure Exceeds Technical Specifications" describes the performance of sur-veillance procedure OP-4209, " Operability Test of the Emergency Diesel Generators" where an inadequate procedure review resulted in the omission of guidance necessary to perform the surveillance within Technical Specification limits.
Specifically, prerequisite instruc-tion to disconnect electrical power from CS-MOV-532 low pressure safety injection (LPSI)
recirculation isolation valve was not included in the revision being used.
The licensee adequately addressed technical deficiencies.
No safety limits were exceeded.
Procedure OP-4209 was thoroughly reviewed and revised.
Long term corrective actions included a review by senior management to improve the quality of procedure revision.
The LER fulfilled the above criteria and no reporting deficiencies were identified.
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10s, Review of Licensee Response to NRC Initiatives 10.'1 Bypass of Non-Essential Diesel Generator Trips (TP 87-07)
TI 87-07, " Bypass of Non-essential Diesel Generator Trips," addresses a potentially generic issue wherein emergency diesel generator (EDG)'
non-essential protective trips are not bypassed under loss of offsite power (LOOP) or loss'of coolant accident (LOCA) scenarios.
The inspector reviewed the Yankee Nuclear Power Station (YNPS)' Final.
Safety Analysis Report, training department system descriptions, and applicable electrical drawings to determine z the number and type of-trips ~ associated with the EDG's, and to identify any circumstances during which. non-essential trips might defeat EDG' safety functions.
At YNPS, the EDG protective trip functions are all considered essen-
.tial and are not bypassed under loss of coolant accident or loss of.
power scenarios.
Therefore, the concern identified by TI 87-07 is not. applicable to-this facility.
The inspector had no further questions.
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10.2 NRC Information Notice 89-33: Potential Failure of Westinghouse Steam Generator Tube Mechanical Plugs-This NRC notice describes a. February 1989 event in which North Anna Unit 1 experienced a steam generator tube rupture. Post event inves-tigation determined a failed hot leg mechanical tube plug had been propelled by primary system pressure the length of the affected tube until it impacted and punctured the outer curvature of the tube.
Preliminarily, Westinghouse indicated the failure mechanism was intergranular carbide precipitation induced cracking, possibly due to a low annealing temperature during milling. Westinghouse has initi-ally identified plugs from two specific heat lot numbers as being most susceptible to this pbnomenon. The tube plugs in place at YNPS are not from the effected heat lots. Because of the dimension of the YNPS steam generator tubes, the plugs must be special ordered manu-factured. Based on available information the licensee has concluded that immediate action is not required in response to this event. The licensee will continue to assess new information as it becomes avail-able. The inspectors had no further questions at this time.
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11. ' Review of Periodic and Special Reports i
Upon receipt, the inspector reviewed periodic and special reports submit-ted to the NRC pursuant to Technical Specifications.
This review verif-ied, as applicable:
(1) that the reported information was valid and included the NRC-required data; (2) that test results and supporting information were consistent with design predictions and performance spec-ifications; and (3) that planned corrective actions were adequate for i
resolution of the problem.
The inspector also ascertained whether any reported information should be classified as an abnormal occurrence.
The-following reports were reviewed:
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Monthly Statistical Report for plant operations for the months of February and March 1989, 12. Management Meetings At periodic intervals during this inspection, meetings were held with senior plant management to discuss the findings. A summary of findings for the report period was also discussed at the conclusion of the inspec-tion and prior to report issuance. No proprietary information was identi-fied as being included in the report.
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