IR 05000338/1979015
| ML19242A080 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 05/10/1979 |
| From: | Cantrell F, Kidd M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML19242A070 | List: |
| References | |
| 50-338-79-15, 50-339-79-21, NUDOCS 7907310203 | |
| Download: ML19242A080 (14) | |
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UNITED ST ATES 88Goq NUCLEAR RECULATORY COMYlSSION
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g.. w.. f Report Nos. 50-338/79-15 and 50-339/79-21 Lit.ensee: Virginia Electric and Power Cocpany P. O. Box 26666 Riclu::ond, Vir ginia 23261 Facility Name: North Anna Units I and 2 Docket Nos. 50-338 and 50-339 License Nos. NPF-4 and CPPR-78 Inspection at Ncrth Anna Site near Mineral, Virginia
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M.~S. Kidd
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Date Signed Inspector:
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e d, Date' Signed
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Approved by:F.S.Cantrell,Actiny4ectionChief,ROSSEranch SUMMARY Inspection on March 3-30, 1979.
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Areas Inspected Unit 1 Areas Inspected the resident inspector involved twelve canhours This routine inspection b, onsite of previously identJied enforcerent matters, previously identified open items, plant tours, and licensee events.
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Unit 1 Findings No apparent items of noncocpliance or deviations were identified.
Unit 2 Areas Inspected This routine inspection by the resident inspector involved forty canhoarsf onsite of previously identifiecf open itees, previously identified itees oreports pe I
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rioncompliance, preoperational test witnessing, plant tours,regarding readiness
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for C)h 50.55(e) and/or 10 CFR 21, and plant status initial fuel loading.
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~2-S u1=a ry Unit 2 Findings Of the six areas inspected, no apparent items of noncompliance or deviations One apparent deviation was identified in one were identified in five areas.
area (f ailure to approve procedures to post changes to controlled drawings by the date corsitted to - paragraph 3).
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DET/ILS 1.
Persons Contacted Licensee Employees
- W. R. Cartwright, Station Manager N. B. Dillon, Superintendent of Construction Testing
- J. D. Kellams, Superintendent of Station Operations
- D.m. McLain, Engineering Supervisor J. V. Ogren, Administrative Supervisor P. G. Perry, Resident Engineer P. A. Slatter, Resident QC Engineer - Construction
- E. R. Smith, Superintendent of Technical Services Other licensee employees contacted included two test engineers and four office personnel.
Other Organizations R. J. Daly, Lead Advisory Engineer, Stone and Webster Engineering Corp. (S&W)
W. L. Lehrbeck, Assistant Lead Advisory Engineer (S&W)
J. B. Howard, Senior FQC Inspector (S&W)
T. C. Mitchell, Senior Construction Engineer (S&W)
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- Attended one or more exit interviews.
2.
Exit Int e rview inspection scope and findings were summariz d on March 9, 23 and 1 above. The devia-The for those persons indicated in Paragrapi 30, 1979 discussed in paragraph 3 was acknowledged by station canagement tion on March 23, 1979.
Licensee Action on Previous Inspection Findings 3.
Lack of Adequate Maintenance (338/78-37-03):
(Closed) Infraction Corrective and preventive ceasures specified Controlling Procedures.
of Janua ry 4, 1979 sere verified to be in the licensee's response referenced maintenance operating procedures, NDP 90.5 complete.
The and 90.6, were revised January 31, 1979. This item is closed.
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Failure of Docnnent Control Progra=
.h (0 pen) Infraction (339/78-32-01):
response to this item, dated
to Update Dra ings.
The licensee's
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January 4, 1979, stated that procedure revision to assure posting of
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1979. The changes to drawings vould.be accocplished by February 1, i
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referenced, administrative procedure 43.41 was not actually procedure 1979 Another procedure required to fully approved until March 5, corrective and preventive sneasures had not been approv ieplement the conclusion of the inspection period. This item appears to be a deviation against the con =iteent given in the January 4,1979 letter (339/79-21-07).
4.
Unresolved Itecs Unresolved items were not identified during this inspection.
Follovup on Previously Identified Items Missing Shear Pins in Auxiliary Feedwater Purp Turbine Base Plate a.
'(339/78-10-05)
The final report per 10 CFR 50.55(e) on this problem was sub=itted August 18, 1978 (Serial humber 350).
Following testing of the driven purp during hot f unctional testing, shear pins turbineinstalled pec Engineering and Design Coordination Reports Review cf were (E&DCR) PS-355-1, PS-355F-2, PS-355G-2 and PS-355-J-2.
the completed E&DCR's and observation of the pump turbine on March 19, 1979, confirmed installation of the shear pins as recoccrended by the vendor. This item is closed.
Broken Service Water Guy Wires (338/78-30-04 and 339/78-24-01)
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for Unit I and
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reported as a licensee' event report This event, under 10 CFR 21 and 10 CFR 50.55(e) for Unit 2, was last discussed 50-338/78-30 and 50-339/78-28, Details I, in IE Report Numbers DurinE the current inspection, cocpleted E&DCR.'s paragraph 7.c.
and design change packages (Unit 1) were reviewed to verify cables. E&DCR's percanent replacement of all spray riser supportreviewed inc for Unit I and P-2t27 through P-2407C for Unit 2.
Also, design change packages 75-76 and FC-78-36 vere reviewed relative to Review of these documents revealed that all support Unit 1. for spray risers on the Units 1 and 2 spray headers had cables been replaced, thus these items are closed.
Service Water Spray Pond Ef ficiencv/Sp_ ray _ Flows and Pressure (33b/76-30-02and339/76-01-05)
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Discrepancies
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As noted in IE Report 50-339/78-01, Detsils I, paragraph 6.e.,
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the therral ef ficiency of the r. rvice water spray pond was ques-
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j tiened in a licensee report per 10 CFR 21 and 10 Cth 50.55(c) on
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Deceeber 28, 1977 (serial number 610).
In addition, a Unit I
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licensee event report (t.ER) 77-05, was submit ted on the sa:ne
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subject per Unit 1 Technical Specifications (open item 339/78-01-05).
Subsequently, letter number 237, dated May 5, 1978, was submitted to Nuclear Reactor Regulation (NRR) to describe the the ncal test (previously planned) to be conducted on the perforcance The testing program was further described in letters re s e rvoir.
A final repcrt on the 237A, 237B, and 237C of various dates.
results of this testing was forwarded to NRR via letter 237D on March 8, 1979, which traascitted the licensee's const1tants report entitled " Service Water Reservoir and Spray Sysica Perfor-mance Testing and Evaluation." In that NRR has price responsibility for review of those test results, licensee personnel vere inforced that IE had no further questions at that time on ef ficiency of the reservoir.
Letter 237D also discussed other problems associated with the projected increased service water tecperatures under accident conditions due to the reservoir being less ef ficient that originally involved service sater cooling of the charging believed.
One pump coolers, which had previously been reported per 10 CFR 50.55(e) and 10 CFR 21 wherein it was believed that the coolers and associated piping had not been cleaned adequately (open items 339/79-12-01).
This latest finding regarding 338/19-09-05 and inability to maintain proper temperatures on the pucp coolers due to increased service water temperatures obviated the needs for cleaning of the piping and coolers, in that the piping is to be increased in size.
The letter states that \\IPC0 intends to complete this modification prior to Unit 2 full load.
Items 338/79-0S-05 and 339/79-12-01 remain open.
A new problem discussed in letter 237D involved potential overloading of the control room air conditioning chillers for service water limit of 110 F. Modifications temperatures in excess of the new are to be made to these chillers to assure they will not overload prior to Unit 2 fuel load (open items 33S/79-15-01 and 339/79-21-01).
Also discussed in letter 237D is the reanalysis /revork of service water and compoaent cooling water piping and pipe supports due to This had been the increased service water tecperature limits.
previous discussed as open item 339/7S-36-01 for Unit 2 and cust Unit I had been previously be resolved prior to Unit 2 fuel loading.
33S/79-15-02 is analyzed for temperatures up to 95 F. Open ite:
identified to follow the reanalysis for Unit 1.
In eakin2 preparations. for conduct of the therril efficiency test, licensee personnel become aware that too tany spray nozzles
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had been installed on three of the 2 via letter number This error was reported per 50.55(e) for Unit 396 on June 13, 1978 and per Unit I as LER 78-49 (33S/78-30-02
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and 339/78-01-05). As discussed in IE Report 50-33E/78-30 and 50-339/78-26, Details I, paragraph 7.a., the appropriate number of nozzles had been plugged to assure that des.gn flows and
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pressure drops at the nozzles were achievable. It was anticipated that the thereal ef ficiency test data would dezonstrate the flows and pressure drops, but it did not.
On March 30, 1979, VEPC0 submitted letter 396A which iticluded a plot of data gathered during testing which confirced that design flows and pressure drops of 53 gp and 7 psi had been obtained.
Open items 338/78-30-02 and 339/78-01-05 are closed.
Lach_of_In_dep)endence Control Room Air Conditioning Systems d.
(339/79-12-02 This Unit 2 problem was reported to NEC per 10 CFR 50.55(e) and 10 CFR 21 via letter 037 dated January 18, 1979. Air Handling Units 2-HV-AC-06 and 2-HV-AC-09, which were powered fro: the "2J" Etergency Bus had their piping connected so as to normally receive chilled water from chiller 2-HV-E-04A, which was powered from the
"2H" emergency bus. Air handling units 2-EV-AC-07 and 2-EV-AC-08 which were powered f rom the "2H" ecergency bus had their piping connected so as to receive chilled water from chiller 2-EV-E-04B,
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which was powered from the "2J" emergency bus. Thus a failure of either emergency power source would disable both of the redundant and ecergency switchgear roo= sir subsystems for control room
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conditioning.
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The solution to this problem, given by EADCR P-2536-2, was to interchange the supply and return chilled water lines for the air handling units such that the norcally aligned chiller would be
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powered frc: the same emergency bus as the air handling units being supplied.
The cocpleted E&DCR and a cirked-up as built print (FB-26H) were used in observing the above changes on March 26, 1979. The inspector had no questions on the piping changes cade.
As shown on station drawings 11715-TB-40C and FB-26H, any of the three Unit chillers can be aligned to service any or all of the four Unit 2 air handling units.
Valve lineups to assure that chillers and air handling units used together are fed f rom a coccon pcser supply must be specified by the operating procedure for the system. As of March 29, 1979, operating personnel were
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awaiting revised prints in order to revise the operating procedure.
This procedure will be reviewed following revision, thus item 339/79-12-02 remains open.
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6.
Preorerational Test Vitnessing Unit 2 Portions of the following tests were witnessed during the inspection period. During these tests, the following were observed for conformance to station adcinistrative and VLI'CO's Nuclear Power Station Quality Assurance canual procedures:
Latest revisions of test procedures available and in use.
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prerequisites and initial plant /systec conditions niet on a Test
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sacpling basis.
Special test equipment required were calibrated and in service.
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Tests perforced per approved p-ocedure or procedure changed per
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NPSQAM.
Significant events, unusual con.itions and test discrepancies
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were documented.
Crew actions appeared to be coordinated.
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Procedure reviews and approvals were in conformance with 'he
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NPSQAM.
ed to be the latest revisions.
Drawings in use were '
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Quality control engineers were present to witness all or portions
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of each tes', utilizing approved checklists.
Specific tests vitnessed were as follows:
2-PO-36.3, Safety Injection Evstem Functional Test Pu p Perforrance a.
36.3, Saf ety injection System Functional Test Purp Pe rf orcance Verification that Testing per section 4.4 of this procedure, which verifies the charging purps (high head safety injection) can take suction from the discharge of the low head safety injection pu ps (LHSI)
was observed on N rch 5, 1979. The atteept to demonstrate flow from 2-SI-P-1A to 2-Cll-P-1A vas unsuccessful due to an icproperly a later aligned valve. The test was successfully completed at date.
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In preparation for witnessing the test, it was noted that only
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Following discussions on
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this, the tent engineer prepared a change to the precedure per the NPSQAM in order to test the second purp.
L, ults of this later date as part of the test procedure vill be reviewed at a
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Observations of another IE inspector routine inspection program.
who witnessed the test are documented in IE Report Nu ber 339/79-15.
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2-PO-66, DC Power System Test test of station battery 2-II was conducted A repeat dischargesection 4.4 of this procedure. The original March 7, 1979 per was satisf act ory, but was repeated af ter replacecent of two test cells. The test method, including test equipment bookups were observed, along with periodic observations of battery voltage and The actual time to discharge the battery discharge load snperage.
to 105VDC was longer than the minicum specified by the vendors, thus there were oc questions on the results of this portion of the test.
2-PO-70, Erargency Diesel Load Test During Sicultaneous Safety c.
Injection and Loss of Normal Emergency Power This test is designed to demonstrate road shedding of ecergency buses during an emergency start of the diesel generators, demon-strate f requency and voltage recovery from loading of equip =ent verify proper sequencing of the buses in sequence, back onto loads, and verify that bus loads do not exceed capacity. Prepara-tions for and testing of diesel generator 2H per sections 4.1 and
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4.2 of PO-70 were observed by this inspector and another IE inspector (Report 50-339/79-18) on March 15 and 16,1979. Overall equipment performance appeared satisfactory with one possible f requency control on the diesel generator appeared exceptiou; Results were to be reviewed by licensee personael to erratic de t e rci ne acceptability.
The results will be reviewed by IE as part of toe routine inspection program.
7.
Plant Tourc Tours of selected plant areas were cenducted on March 7,13,15, and 21, 1979 with emphasis on Unit 2.
During the tours, the following iters, as available, were observed:
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Hot Work Adequacy of fire prevention /pratection ceasures used.
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Fire Equipment Operability and evidene,- of pe: iodic inspection of fire suppression i
{*,g equipment.
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Housekeeping Minical accumulations of debris and maintenance of required cleanliness levels in systems under or following testing.
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Equipment Preservation
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Maintenance of special preservative measures for installed equipment as applicable.
{ceponent Tagging e.
Icplementation and observance of equipcent tagging for safety or equipment protection.
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Instrumentation Adequate protection for installed instrumentation.
Communication g.
Ef f'ctiveness of public addrecs system in all areas toured.
E uipernt Controls h.
Ef fectiveness of jurisdictional controls in precluding unauthorized work on systees turned over for initip1 operations or preoperational testing.
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Foreign Material Exclusion Maintenance of controls to assure systees which have been cleaned and flushed are not re-opened to admit foreign caterial.
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Security leplementation of security provisions for both Units.
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Portions of testing conducted per 2-PO-36.3, 2-p0-66, and 2-PO-70 are discussed in paragraph 6 of these were observed. Findings Detiils.
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obsc cved, ne items of noncocpliance or deviations Within the areas
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were noted.
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Unit 2 Status - Readiness for Fuel Loading 8.
The licen ee's official estimate of Unit 2 readiness for initial full
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loading r<tains April 30, 1979 As of March 29, 1979, 50 of a total Of those, about 18 of 93 preoperatio:.al tests had been cornleted. review process an were in the
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Several other tests were in progress at the conclusion of the inspection The following list represents known activities retaining to period.
be ccepleted on problems to be resolved prior to IE:II making a finding that Unit 2 would be ready for an operating license.
General Items a.
evaluation of test of preoperational testing, Co=pletion (1)
results, and resolution of sigrificant test deficiencies.
Coeplete developcent and approval of startup test procedures (2)
and operational procedures recorcended by Regulatory Guide 1.33.
(3)
Irplementation of the security program for Unit 2.
b.
Enforcement Items Infraction - Contrary to Criterion VI of Appendix B to 10 (1)
CFR 50, the document control prograe does not assure updating of drawings held by operations and test personnel (76-32-01).
Deviation - Frilure to implecent corrective ceasures on item (2)
(1) above by the date coreitted to in the response to the Notice of Violation (79-21-07).
I Unresolved Itec c.
I structures is hampered by lack of baseline Surv-illance lac-
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or continuous o.
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Outstanding Itecs (1) Resolution of low tegger readings on recirculation spray
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pump motors (77-35-05).
of modifications to the outside recirculation Corpletion (2)
spray system to preclude FPSH problems (76-05-04).
Installation of reactor vessel shieliing to prever.t excessive
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ra distion levels in contair. ment (78-12-02).
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Seismic analysis not performed after modification to insula-(4)
tion on reactor vessel lower head (78-24-02).
(5) Bending stresses on embed:ent plates for upper steam generator support plates not checked for snubber tension loading (79-24-05).
Verify adequacy of service water and component cooling water (6)
supports to resist thermal loadings over service water pipe temperature range (78-36-01).
outside end of spare contain=ent (7) Installation of caps on piping penetrations (78-36-02).
Resolution of break in fiberglass service water spray pond (8)
piping (78-36-05).
to charging pump coolers and (9) Cocple ion of modificationsremoval capability of service water piping to ensure heat system (79-12-01).
(10) Verification of environmental qualification of Class I electrical equipment (IEB 79-01/78-28-01).
used in reactor (11) Dete rmine if atypical weld material was vessel seam welds (IEB 7 8-12, 12A, 12B).
to assure electrical (12) Revision of operating procedures (s)
independence between redundant subsystems for control room air conditioning (79-12-02).
Replacement of recirculation spray purp motor which had a (13)
defective bearing housing (79-12-03).
s Resolution of lack of seismic supports and missile protection (14)
exhausts and sufflers for the emergency diesel generator (79-12-04).
the of potential for hydraulic transients on Resolution (15)
recirculation spray heat exchangers (79-12-04).
Deconstration of operability of AC and DC solencid valves (16)
VEPCO letter nu bers 114, which cay have parts missing.
dated February 23,,1979 identified a potential defect deficiency per 10 Cin 21 and 10 CFR !3.55(e) involving solenoid valves.
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Certain of the solenoids were found to have rissir.g parts, Investigation of the problem
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such as coil. retainer clips.
has begun and all solenoids will be verified operable prior to Unit 2 fuel loading (239/79-21-02),
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Resolution of problem areas associated with the operational (17)
50-339/79-11.
quality assurance program defined in IE Report (18) Cocpletion of modifications to the control room air condition-ing chiller units to preclude overloading under certain to increased service water tecperature (item
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339/79-21-01; see paragraph 5.c of these Details).
VEPCO reported per 10 CFR 50.55(e) and 10 21, 1979, (19) On March certain Velan check valves used in Unit 2 had CFR 21 that be:n supplied with incorrect weights listed on their drawings.
A s.;tten report per 10 CFR 21 was submitted March 26, 1979 (number 189). The true weightr, approxicately double that cust be used in reanalyzing piping and given on drawings tupports affected. Reanalysis and any resultant rework is to he complet ! prior to fuel load (329/79-21-03).
1979, VEPC0 reported per. CFR 21 and 10 CFR Da March 21, (20)
50.55(e) that certain air operated valve limit switch actuating a ms were subject to bending due to forces ieposed on them Letter number 190 was subtitted by heavy duty limit switches.
Affected valves will be per 10 CFR 21 March 26, 1979.
re. corked to assure proper long term operation prior to fuel
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load (339/79-21-04).
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(21) On March 21, 1979, the inspector was advised by station that during cleaning of the reactor coolant management
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piping, cracks bad been discovered in the flow-straightening device (flow splitter) in the suction line for Unit 2 reactors coolant pump (RCP) "C".
This defect was reported to IE:II 22, 1979, and <
per 10 CFR 50.55(e) and 10 CFR 21 on March 27,1979 (Serial No written report was submitted March Metallurgical and chemical analyses were in progress at the cocpletion of the inspection period.
As of March 30, no evidence of what caused the cracks had been conclusive Visual and liquid penetrant inspections of the discovered.
for loops "A" and "B" revealed no cracks in flow splitters use ultrasonics had proved inconclusive them.
Attemps to 30, 1979, but station personnel expressed hope through March this might be a usef ul method of exacining the splitters that in Unit 1.
Detereination of cause, along with repair or other resolution must be accocplished prior to fuel load t
(339/79-21-05).
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VEPCO reported per 10 CFR 50.55(e) that a
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(22) On March 29, 1979, Klockner-Moelles motor cont rol center starter for Unit 2 valve MOV-RS-201B had failed due to shorting between phases.
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Two similar failures had also been reported per 50.55(e) in 1977 (See letter 163 dated June 14, 1977). Eesolution of this matter cust be resolved prior to fuel loading (339/79-21-06).
9.
Unit 1 Events /Proble Areas inspection period, the following Unit 1 events and Unit 2 During the problems which could ef fect Unit I were reported:
Overwei2 t Check Valves _
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On March 20, 1979, licensee management inforced the inspector certain check valves used in safety injection (SI) systets that had been supplied by k'estinghouse with incorrect weights on their This constituted drawings (235 pounds versus actual of 450 pounds).
Reanalysis a prompt LER (79-35) per Unit 1 Technical Specifications.
of piping stresses revealed one six inch low head S1 line wherein calculated stresses exceeded code allowable licits, but the calculations did not exceed material strength based on certifications During discussions on this problem, IE and of those materials.
- iRR concurred with the VEPCO position that modifications would be made to the support (s) for this line during an outage planned for April 12,1979, but before April 16, 1979. This vill be reinspected and is identified as open item 338/79-15-03).
b.
AC/DC Solenoid Valves
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As discussed in paragraph 8.d.(16) of these Details, e potential problem with AC and DC solenoid operated valves was identified on Unit 2 via a verbal report on February 20, 1979. The problem involved a rework of these solenoids to replace their coils with ones with a higher temperature rating. During the rework effort
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on Unit 2, certain parts, such as retainer clips had been left out during reassembly, resulting in possible failure to operate.
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Unit I solenoids had apparently been replaced earlier with more thus station manage =ent was quality control coverage, in Unit 1.
At the complete confident that a similar problem did not exist conclusion of the inspection period, a listing of Unit i valves possibly af fected was being generated and plans being forculated This will be reinspected and is identified for inspection of them.
as open item 338/79-15-04.
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Valve Limit Switch Arms c.
As noted in paragraph 8.d.(20) of these Details, VEPC0 reported
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\\3 per 10 CFR 21 and 10 CFB 50.55(e) for Unit 2 that certain air operated valve limit switch actuating arms were subjected to
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bending due to forces ieposed on thee by heavy duty limit switches.
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-12-Unit 1 employs identical limit switches, but station management felt this was not reportable under Unit 1 Technical Specifications a review had. concluded no adverse action would result in that even if the actuating a rms were bent. This will be reviewed further and is designated as open itec 338/79-15-05
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Cracks in Reactor Coolant Pump Flow Straightener d.
As discussed in paragraph 8.d.(21) of these Details, two cracks were discoverd in the flow splitter in Unit 2 RCP "C" suction the line on March 21, 1979.
Investigations were in progress at conclusion of the inspection period to determine cause(s) of the cracks and determine vnether inspections of the Unit I splitters would be made, and if so, how.
Inspection of this matter is continuing and is identified as open item 338/79-15-06.
Nonconservatism in Analysis for Dropped Control Rod e.
On March 29, 1979, station management reported that a potential nonconservatism had been discovered by Westingbouse in its analysis of the single dropped rod event. This pro:pt LER (79-41) involves potential power overshoot and resultant departure from nucleate boiling (DNB) ratios lower than previously believed for a case where a control red adjacent to the power range nuclear instrument
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used for rod control drops into the core, resulting in the rod control systec pulling other rods out to cocpensate for power decrease.
This problem does not effect plants, which use an auctioneered (high) power range signal for rod control.
No im=ediate concerns is evident for Unit 1 in that control bank "D" is operated out or nearly out of the case, which cinicizes power This problem wi?1 be inspected further and is designated overshoot.
open item 338/79-15-07.
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