IR 05000271/1989021
| ML19354D881 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 01/08/1990 |
| From: | Blough A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML19354D880 | List: |
| References | |
| 50-271-89-21, NUDOCS 9001230116 | |
| Download: ML19354D881 (13) | |
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U.S. NUCLEAR REGULATORY COMMISSION
REGION I
Report No.
50-271/89-21 Docket No.
50-271 License No. OPR-28 Licensee:
Vermont Yankee Nuclear Power Corporation RD 5 Box 169 Brattleboro, Vermont 05301 Facility:
Vermont Yankee Nuclear Power Station Inspection At: Vernon, Vermont Inspection Conducted: October 17 - December 11, 1989 Inspectors:
Geoffrey E. Grant, Senior Resident Inspector John B. Macd nald Resident Inspector Approved by:
s, A. Randy Bloug% Chief, Reactor Projects Section 3A Date Inspection Summary:
Inspection on October 17 - December 11. 1989 (Report No.
Areas Inspected:
Routine inspection on daytime and backshifts by two resident inspectors of: actions on previous inspection findings; operational safety; security; plant operations; maintenance and surveillance; engineering support; radiological controls; licensee event reports; licensee response to NRC initi-atives; and, periodic reports.
Results:
1.
General Conclusions on Adequacy. Strengths or Weakness in Licensee Programs The licensee emergency technical specification (TS) change request regard-ing the uninterruptible power supply system (UPS) was well planned and comprehensively documented.
The submittal contained sufficient technical bases to support NRR issuance of a temporary waiver of compliance pending review of a permanent TS amendment (Section 6.1).
The repetitive periods of unavailability experienced by the UPS-1A unit during this inspection period were typical of difficulties the UPS units have presented the licensee in the recent past.
The maintenance depart-ment continued to address each failure in a controlled and technical man-The licensee decision to replace the UPS units as well as continuing ner.
corporate and plant management oversight of the UPS system performance are indicative of a conservative philosophy toward the availability and reli-ability of safety related equipment (Section 7.1),
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TABLE OF CONTENTS PAGE 1.
Persons Contacted....................................................
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Summary of Facility Activities.................................-..~....
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Status of Previous Inspection Findings (IP 92700, 92702, 93702*),....
1-3.1 (Closed) Unresolved Item 89-01-03: Demonstrate PORC Fulfillment
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of Technical Speci fication Requirements.......... w............
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3.2 (Closed) Unresolved Item 88-08-06:1 Actions to Prevent / Mitigate Activity Release Via the Radwaste Cask Room...................
2-3.3 (Closed) Violation 88-14-04: Failure of Obtain TS-Required Grab Samples When Service Water Radiation Monitor was Inoperable...
3.4 (Closed) Unresolved Item 88-08-05: Im Methodology........................ prove Event Noti fication 3
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3.5 (Closed) Unresolved Item 85-22-02: Establish Program for Vendor
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Information Update............................................
3.6 (Closed) Unresolved Item 86-22-05: Complete Changes to Technical (
Speci fications for Various NUREG 0737 Items...................
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3.6.1 (0 pen) Unresolved Item-89-21-01: Continuing NRR:NRC l
Review of the Licensee Overtime Procedures..........
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3.7 (0 pen) Violation 89-04-01: Inadequate Verification of F
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S u p p re s s i o n.......................................... i re
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Operational Safety (IP 71707).........................................
i 4.1 Plant Operations Review.......................................
4.2 Safety System Review...........................................
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4.3 Inoperable Equipment............................................
j 4.4 Review of Temporary Modifications................................
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4.5 Review of Switching and Tagging Operations.....................
4.6 Operati onal. Sa f ety Fi ndi ng s......................................
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Security (IP 71707)...................................................-
5.1 Observations of Physical Security...............................
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Plant Operations (IP 71707,93702)................-...................
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i 6.1-Temporary Waiver of Compliance..................................
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Table of Contents PAGE 7.
Maintenance / Surveillance (IP 71710,61726,62703)....................
8-7.1 UPS-1A Inoperability............................................
7.2 RHR Service Water (RHRSW) Valve Inoperabi11ty...................
7.3 Emergency Diesel Generator (EDG) Maintenance....................
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Review of Periodic and Special Reports (IP 71707)....................
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Ma na geme n t Me eti ng s ( IP 30703 )........................................
- The NRC Inspection Manual inspection procedure (IP) that was used as inspec-tion guidance is listed for each applicable report section, v.
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DETAILS 1.
Persons Contacted Interviews and discussions were conducted with members of the licensee staff and management during the report period to obtain information per-
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tinent to the areas inspected.
Inspection findings-were discussed peri-
odically with the management and supervisory personnel listed below.
Mr. P. Donnelly, Maintenance Superintendent Mr. R. Grippardi, Quality Assurance Supervisor Mr. S. Jef ferson, Assistant to Plant Manager Mr. J. Herron, Operations Supervisor Mr. R. Lopriore, Maintenance Supervisor-Mr. R. Pagodin, Technical Servicer Superintendent Mr. J. Pelletier, Plant Manager Mr. D. Porter, Shift Supervisor Mr. R. Wanczyk, Operations Superintendent i
Mr. T. Watson, I&C Supervisor 2.
Summary of Facility Activities
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i Vermont Yankee Nuclear Power Station (VYNPS or-the plant) continued full power operations during this -eport period. Throughout the-period. short
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term scheduled power reductions to 80-95% of full power were conducted weekly to perform routine.surveillances of control rod drives, main tur-bine and by pass valves. 'On November 18, power was reduced to 40%-to i
accomplish a rod pattern exchange and replace recirculation pump motor
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generator brushes.
Return to full power was achieved on November 23.
On November 7, the licensee informed the NRC Operations Center via the l
Emergency Notification System (ENS) when the Ames Hill communication transmitter was removed from service to implement equipment upgrades.
This notification was made in accordance with-10 CFR 50.72 criteria.
Notifications were also made on November 29 when a spurious radiation monitor spike resulted in a Group III primary containment. isolation system isolation, on December 2 when several civil defense sirens were declared.
inoperable, and on December 3 when the ENS phones were temporarily out of service.
Security notifications were made on December 9 when the licensee determined a security system capability had temporarily degraded and on
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December 10 (as an informational call) when an individual-arrested at the Maine and Canadian boarder made a vague threat regarding_ potential ter.-
rorist activity at nuclear facilities. :The threat was later recanted by the individual.
3.
Status of Previous Inspection Findings
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3.1 (Closed) Unresolved Item 89-01-03: Demonstrate PORC Fulfillment-of
Technical Specification Requirements. This. issue addressed a lack of
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plant operations review committee (PORC) review of an unanalyzed
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plant condition and subsequent justification for continued' operations (JCO).
The licensee revised AP 0030, "The Plant Operations Review
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Committee," in September 1989.
The revision both expanded and clari-
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fied PORC responsibilities to ensure fulfillment of TS 6.2.A.6 re-quirements. The inspector also noted that PORC review of temporary
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modifications requiring safety analyses (a previously identified de-ficiency) was also addressed in the revised AP 0030.
The inspector attended PORC meetings, observed PORC-related activities and-reviewed
PORC meeting minutes to ascertain performance in this area.
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stantial improvement in this area was noted. The licensee has demon-
strated a continuing ability to fulfill PORC-related TS requirements.
This item is closed.
3.2 (Closed) Unresolved Item 88-08-06: Actions to Prevent / Mitigate Activity Release Via the Radwaste Cask Room.
This item addressed licensee-
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identification of evidence of radioactivity leakage from the radwaste building resin cask room.
A special survey. detected activity in the
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asphalt under the cask trolley tracks.
Further licensee investiga-
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tion found evidence of trace-fixed activity in and under the asphalt.
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The licensee implemented a number of operational and programmatic.
improvements to control the situation including: extensive procedure revision, improved cask decantamination techniques,~ building hardware-improvements, increased radiological monitoring frequency and cap-ability, and imp' roved survey techniques.
Inspectors have: observed cask operations and found the~ improvements to be effective in miti-gating further release. This item is closed.
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3.3 { Closed) Violation 88-14-04: Failure to Obtain TS-Required Grab Samples When Service Water Radiation Monitor Was Inoperable.
This violation
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t addressed a repeat licensee failure to implement TS 3.9.A.1 grab
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l samples requirements when the service Water (SW) radiation monitor was effectively inoperable during other than open cycle operations.
The licensee promptly corrected this condition by requiring daily SW
grab samples regardless of plant operating conditions.
This interim
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measure remained in effect until a technical evaluation of the SW
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radiation monitor could be completed.
The licensee conducted exten-l sive evaluations af.the monitor effectiveness, modified appropriate.
l procedures, improved administrative controls, _ and completed applic-l able training.
Extensive research by the. Yankee Nuclear: Services l
Division formed the basis for a new methodology of ensuring monitor
operability.
The new program involves twice weekly analyses of.reac-I tor coolant to determine the compositt maximum permissible concentra--
L tion (CMPC) and calculation of an equivalent SW radiation monitor count rate. 'If the equivalent count rate is less than the monitor
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alarm setpoint, daily grab samples will be obtained.
This condition would only be expected to occur as a result of a significant change in reactor coolant radionuclide concentrations and proportions. The
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i inspectors reviewed the new program and supporting procedures and
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found no deficiencies.
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The licensee response to this violation was extensive ard well-executed. However, the permanent corrective actions took a year to formulate and implement. Although interim measures were effective in i
ensuring TS requirements were met, a one year delay from the viola-
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tion (eighteen months from problem identification) appears to be
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somewhat excessive. However, other aspects of the licensee correc-tive action process for this issue were good.
This item is closed.
3.4- (Closed) Unresolved Item 88-08-05: Improve Event Notification Methodology.
This item addressed a licensee difficulty with con-.
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sistently and correctly applying the requirements of 10 CFR 50.72 to event notification.
Initial licensee-actions to correct deficiencies-
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in this area were ineffective.
During'the 1989 refueling outage,
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following additional instances of misapplied notification. criteria,
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the licensee substantially clarified internal guidance covering 10 CFR 50.72. This clarifiestion was subsequently incorporated into AP 0156, " Notification of Significant Events." Inspector review of this area shows improved notification performance, and heightened operator and management awareness of notification requirements.
This item is
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closed.
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3.5 (Closed) Unresolved Item 85-22-02: Establish Program for Vendor Information Update.
This item addressed lack of a continuing. program to ensure updated vendor information for safety-related components is identified and incorporated into maintenance and surveillance pro-grams. The item was initially identified during an inspection to review and assess the licensee response to Generic-Letter (GL).83-28, i
" Generic Implications of Salem ATWAS Events." At'.the time of the
inspection the licensee relieo on a variety of internal land external programs, including the Vendor Equipment Technical?Information Pro-
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gram (VETIP), to fulfill vendor interface requirements.
Lack of-licensee improvements to this program was subsequently the subject of NRC performance assessments. The ii:ensee has presently formulated a
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process for vendor manual updates and: improvements.- Inspector review-of the process has determined that it addresses' safety-related equip-i ment manuals and results in a quality product.
Formal NRC:NRR. review -
and acceptance of the licensee response to GL 83-28 has not been com-pleted. However, an NRC:NRR industry-wide review of the. vendor in--
formation aspects of GL 83-28 has been performed and further generic-l guidance relating-to this issue is expected.
Based'upon licensee actions to date and the probable forthcoming generic guidance, this item is currently considered closed.
3.6 (Closed) Unresolved Item 86-22-02: Complete Changes to Technical Specifications for Various NUREG 0737 Items.
This item addressed the need for licensee action to address technical specification?(TS)
- changes related to various NUREG 0737 items and requested-by:GL 83-02. Guidance was provided in GL 83-02 for TS changes for thirteen NUREG'0737 requirements. -The licensee responded by letter to NRC:NRR.
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dated November 3,1987 that nine of the thirteen-items were satis-factorily completed and the remaining four (I. A.1.3, II.K.3.3, II.K.3.13, and II.K.3.22) did not require TS changes.
In November 1988 the licensee requested changes to the TS that covered two (II.K.3.13 and II.K.3.22) of the remaining four items. However, the licensee continued to maintain that NUREG 0737 items I.A.I.3-(staff overtime limits) and II.K.3.3 (safety and relief valve challenges /
failures) did not require change / addition to the TS. _The specific requirements for limiting staff overtime were described in item I.A.1.3 and GL 82-12, and were imposed on the licensee by confirma-
. tory order dated March 14, 1983.
The licensee responded to this issue by incorporating overtime limits into AP 0036 " Shift Staffing."
However, inspector review of AP 0036 determined that during certain scenarios the licensee limits on overtime were less restrictive'than those contained in GL 82-12. Although licensee procedural limits on overtime do not conform to GL 82-12, overuse of overtime has_ typic-ally not been observed as a problem.
In the safety evaluation for Amendment III to the facility license (which closed out items II.K 3.13 and II.K.13.22) NRC:NRR indicated that the licensee.e-sponses of record addressing items I.A.I.3 and II.K.3.3 appeared _to-be acceptable and considered the issue of GL 83-02 to be closed.'
Based on this determination, this unresolved item is closed.
3.6.1 (0 pen)' Unresolved Item 89-21-01: Continuing NRR:NRC Review of the Licensee Overtime Procedures.
As a result of dis-crepancies-identified above between the worker overtime controls established in GL 82-12 and the licensee overtime control procedure, NRR:NRC is readdressing this issue, Final resolution 'of appropriate overtime controls is iden-tified as an unresolved item.
i 3.7 (0 pen) Violation 89-04-01: Inadequate Verification of Fire Suppression.
-I System Operability.
This violation was issued following an NRC de-termination that the licensee had not-performed' adequate-post-installation testing of the CO2 fire suppression. systems in the cable
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vault and diesel fire pump fuel oil tank room-to demonstrate system operability. The' licensee performed' post-installation puff tests of-the systems.
However, the NRC staff concluded the applicable National-Fire Protection Association (NFPA)' Standard required that a full discharge post-installation test be performed. -By letter dated i
August 21, 1989 the NRC indicated'the staff would review an alternate
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to the established full discharge test if a conclusive method can be designed. On October 31, the licensee conducted an alternate cable vault room enclosure integrity test. The test was concluded on j
November 3.
The test addressed the ability of the cable vault and
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its associated CO2 suppression system to withstand the-pressure gene-
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rated during C02 discharge; distribute CO2 uniformly throughout the-enclosure; and, maintain a minimum 50% CO2 concentration for at least ten minutes following initiation.
Prior to initiating the test the
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licensee conducted a 10 CFR 50.59 and PORC quorum review of the pro-cedure and determined the test did not present an unreviewed safety issue.
Based on the results of the test the licensee declared the cable vault CO2 suppression system was operable on November 16.
The compensatory continuous firewatch was discontinued and was replaced by a once per two hour roving fire watch.
It is the intention of the licensee to submit a comprehensive report of the test methodology to the NRC by January 15, 1990.
This issue will remain open pending final staff review of the licensee submittal.
This item is open.
4.
Operational Safety 4.1 Plant Operations Review The inspector observed plant operations during regular and backshift tours of the following areas:
Control Room Cable Vault Reactor Building Fence Line (Protected Area)
Diesel Generator Rooms Intake Structure Vital Switchgear Room Turbine Building Control room instruments were observed for correlation between
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channels, proper functioning, and conformance with technical speci-fications.
Alarm conditions in effect and alarms received in the control room were reviewed and discussed with the operators. Opera-tor awareness and response to these conditions were reviewed.
Opera-tors were found cognizant of board and plant conditions.
Control room and shift manning were compared with technical specification requirements.
Posting and control of radiation, contaminated and high radiation areas were inspected.
Use of and compliance with radiation work permits and use of required personnel monitoring de-vices were checked.
Plant housekeeping controls were observed in-cluding control of flammable and other hazardous materials.
During plant tours, logs and records were reviewed to ensure compliance with station procedures, to determine if entries were correctly made, and to verify correct communication of equipment status.
These records included various operating logs, turnover sheets, tagout and jumper logs, and potential reportable occurrence reports.
Inspections of the control room were performed on backshifts including October 24 and 31, November 22 and 29, and December 11, 1989.
Operators and shift supervisors were alert, attentive and responded appropriately to annunciators and plant conditions.
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4.2 Safety System Review Portions of the emergency diesel generators, reactor core isolation
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cooling, core spray, residual heat removal, standby gas. treatment,
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l residual' heat removal service water,-safety related electrical, and high pressure coolant injection systems were reviewed to verify pro-per alignment and operational status.in the standby mode..The' review included verification that (1) accessible major flow path valves were
correctly positioned: (ii) power supplies were energized, (iii) lubri-cation and component cooling was proper, and (iv) components were
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operable based on a visual inspection of equipment for _ leakage and-general conditions. No violations or safety concerns were identi-fied.
4.3 Inoperable Equipment Actions taken by plant personnel during periods when equipment was-inoperable were reviewed to verify:
technical specification: limits-were met; alternate surveillance testing was completed satisfactor-e ily; and, equipment return to service upon completion of repairs was
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Date Out Date In System t
10/19 10/23 UPS-1A-
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10/25 10/30
"B" RHRSW System 11/01 11/03-
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11/05 11/10 UPS-1A
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11/15 11/18-UPS-1A 11/23 11/25 UPS-1A
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4,4 Review of Temporary Modifications Temporary modifications were reviewed to-verify that controls estab-
lished by AP 0020 were met, no conflict with technical specifications were created, safety evaluations were prepared in accordance with 10
CFR 50.59 if required, and requests were reviewed and approved prior l
to installation.
Implementation of the requests was< reviewed on a-
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sampling basis.
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89-53 -- Implemented on November 1 to modify the logic circuitry. of-the cable vault fire protection system. panel.
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troduces a four minute time delay for the isolation of the cable vault exhaust fan and damper following a CO2 suppression system-in-itiation.
The time delay allows for increased overpressure protec-tion, as well as, improved CO2 distribution.
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i 89-54 -- Implemented on November 1 to install an atomizing air throttle valve on the house heating boiler air intake systems. This modification provides greater ability to regulate and maintain pres-sures at desired valves.
Additionally, several temporary modifications were closed out during--
the' report period. These were reviewed for completeness-and adequacy of system restoration.
4.5 Review of Switching & Tagging Operations The switching and tagging log was reviewed and tagging activities were inspected to verify plant equipment was controlled in accordance with the requirements of AP 0140, Vermont Local Control Switching Rules.
4.6 Operational Safety Findings
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I Licensee administrative control of off-normal system configurations by the use of temporary modifications and switching and tagging pro-cedures, as reviewed in Sections 4.5 and 4.6, was in compliance with.
procedural instructions and was consistent with plant safety..Back-shift inspections have consistently found operators to be. alert and
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attentive.
Ope' rations are routinely conducted in-a professional'
l manner in an atmosphere of quiet control'and-competence. With the.
i exception of isolated instances, overall' plant cleanliness.and mate-
rial condition continue to be. good.
No defici_encies were. identified'
in licensee operations associated with the reviews covered in-Section-l 4.
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Security l
5.1 Observations of Physical Security i
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Selected aspects of plant physical security were reviewed during-i
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regular and backshif t hours to verify that controls were in accord-s ance with the security plan and approved procedures,.This ~ review -
included the following security. measures: guard staffing; vital =and
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protected area barrier integrity; maintenance of isolation zones;'-
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.and, implementation of access controls, includingzauthorization,.
j badging, escorting, and searches.
No inadequac.ies were identified.
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6, Plant Operations l
6.1 Temporary Waiver of Compliance
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On November 5, uninterruptible -power supply (UPS)-1A was declared j
inoperable following the reception of a UPS-1A-unit trip concurrent
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with several failure alarms.
The UPS units, UPS-1A and UPS-1B, nor-
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L mally supply power to the low pressure coolant injection system
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(LPCI)~ injection valves, RHR 25A(B) and 27A(B), respectively.
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fore, the UPS units are considered subsystems of the LPCI system.
Technical Specification 3.5.A.4. permits continued reactor operation for seven days with a subsystem of one LPCI train inoperable, pro-vided the remaining LPCI train-and containment cooling subsystem,' the core spray subsystems and the emergency diesel generators are oper-able. On November 9, following extensive unsuccessful maintenance efforts to restore the UPS-1A to service, the licensee initiated an emergency TS change request to extend the current seven day limiting condition for operation-(LCO) with a single UPS unit inoperable.
Later on November 9, following complete staff. review, NRR issued a-temporary waiver of compliance (TWC) from the requirements _of TS 3.5.A.4.
The waiver, which expired on December-11,1989, extended UPS LCO period from seven days to thirty days. The TWC required; that'the UPS alternate power supply (a parallel Class IE maintenance tie) be aligned to power the affected LPCI injection valves; that'the off-site power source from the Vernon Hydro Dam be available.to be-aligned to the affected emergency bus _(Bus 3 or 4) in the event of'aL loss of offsite power and diesel generator failure; and that appro-priate operator training be conducted..The UPS-1A unit was:subse '
quently returned to service on-November 10, five days after being
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declared inoperable.
The licensee eme'rgency technical-specification change. request was comprehensive and well documented. Appropriate compensatory measures were proposed to support NRR issuance of a TWC.
Inspector review of training records as well as discussions with licensed operators indi-
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cate immediate training of the TWC requirements was effective.
Fur-ther, the licensee reiterated the commitment to replace the current:
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t UPS units with more reliable systems' prior;to' restart from the next'
refueling outage scheduled to begin.in September 1990. The inspec-tors had no further questions.
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Maintenance / Surveillance-7.1 UPS-1A Inoperability l
The UPS-1A power supply experienced extended' periods of unavailabil-ity during this report period on October 19-23, November 5-10, 15-18 -
and 23-25.
Failure analysis of these. events. exemplified the diverse maintenance challenges the UPS units have presented. The failures
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have been attributed to multiple random component fai. lures which are
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largely unpredictable and to spurious unit trips. '/.dditionally, system design dictates that troubleshooting and diagnostic testing be l
performed essentially in a series path such that individual component
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failures can mask or exasperate multiple component failures.
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Maintenance personnel continued to address each UPS failure in a con-trolled and technical manner.
Troubleshooting was performed in accordance with approved procedures ~and vendor manuals. All opera-tional and maintenance evaluations relating to the recovery of UPS-1A were accurately and thoroughly documented in the associated mainten-ance requests.
Plant and corporate management have closely monitored historical UPS system performance.
In December 1988, a feasibility study was initi-ated to examine potential alternatives to the existing units.
In June 1989, the licensee concluded that the UPS units should be re-placed by a system with a more reliable design.
Further, as docu-mented in the temporary waiver of compliance issued by NRR on Novem-i ber 9, 1989 (see section 6.1 for more detail), the licensee committed
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to replace the existing UPS units prior to restart from the_next re-fueling outage.
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7.2 RHR Service Water (RHRSW) Valve Inoperability On October 24, during monthly surveillance stroke testing, RHRSW in-let valve, RHRSW-89B, indicated mid-stroke (dual livht) position fol-lowing a closure signal. Maintenance troubleshooting revealed that i
the valve seat had oecome free of the valve body and settled at an i
angle which prevented full valve stem travel and valve closure. -
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~ l seat was normally tack welded in place, however the welds had eroded and corroded to failure.
The valve seat had been in place since 1978. The licensee corrective actions included a-45 degree fillet seal weld.of the complete circumference of the upper and lower valve body to seat contact interfaces with appropriate pre-and post weld heat treatments. Additionally. the licensee has included visual. in--
I spection of the welds in the outage valve inspection program. The
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valve repairs and post-maintenance testing were completed on October 30.
I Licensee response to the RHRSW-898 failure was noteworthy. The root
cause determination was deliberate and technically sound. : Weld in-
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duced stresses were minimized by the application of weld heat treat-ment techniques. Appropriate quality controls were. evident. The a
inspectors had no further questions.
7.3 Emergency Diesel Generator (EDG) Maintenance The "B" EDG was removed from service from November 1-3, to perform a mid-cycle inspection and evaluation program established to-provide
technical justification to support a one-time extension of. the major
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overhaul periodicity from 12-18 months to 22-24 months.
The scope of
the inspection program was developed in conjunction with the EDG ven--
i dor (Colt Industries-Fairbanks Morse) and included various supplemen-
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tal visual inspections, clearance tolerance checks, vibration moni-
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i toring, and chemical analysis of engine fluids. All parameters in-spected were found to be satisfactory with exception of excessive
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l clearance tolerances in the upper vertical drive assembly.- The ob-served tolerances were indicative of potential bearing wear or spacer wear between the thrust and roller bearing.
The vertical drive assembly is not routinely inspected therefore the licensee' lacked data necessary to determine the cause or rate of degradation, or if the observed clearances had existed since-assembly installation.
Following consultation with the vendor, the licensee restored all vertical drive assembly components to' design. tolerances and estab-lished an accelerated vertical drive assembly inspection frequency, The assembly was inspected after approximately eight operational hours and all component tolerances remained constant at design values. The next inspection is planned after an additional sixteen hours of operation have been accumulated.
The inspections will con-tinue until the periodic overhaul of the "B" EDG is performed. The'
overhaul is currently planned for_ April 1990.
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The licensee demonstrated a sound analytical approach toward the de-velopment of a technical evaluation-to support an extension of_the-EDG overhaul periodicity. Appropriate critical parameters were iden-tified and vendor concurrence of the inspection program was_obtained.
The licensee and the vendor continue to evaluate:the potential causes for the observed vertical drive assembly clearances.
In:the interim
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the licensee has established a conservative visual inspection sched-
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ule for the assembly.
The inspectors will review the results of:
these inspections and have no further questions at this time.
8.
Review of periodic and Special Reports Upon receipt, the inspector reviewed periodic and special reports sub '
d mitted pursuant to Technical Specifications.
This review verified,.as-l 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 specification; Land.-.
.i (3) that planned corrective actions were adequate for_ resolution of the
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problem. The inspector also ascertained whether any. reported information should be classified as an abnormal occurrence. The following reports-jl were reviewed:
Monthly Statistical Report'for plant operations for the months of>
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October and November 1989.
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Feedwater leakage detection system monthly performance summary for
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i months of October and November 1989.
9.
Management Meetings
i At periodic intervals during this inspection, meetings 'were held with
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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 iden-i
,
tified as being included in the report.
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