IR 05000271/1998006

Insp Rept 50-271/98-06 on 980407-0521.Violations Noted.Major Areas Inspected:Aspects of Licensee Engineering & Technical Support Operations Pertaining to Basis for Maint Operations Process

ML20236M235
Person / Time
Site:	Vermont Yankee
Issue date:	07/02/1998
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20236M212	List: IR 05000271/1998006 ML20236M209 ML20236M232
References
50-271-98-06, 50-271-98-6, NUDOCS 9807130358
Download: ML20236M235 (13)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION I

Docket No: 50 271 License No: DPR 28 f

Report No: 60 271/98-06

Licensee: Vermont Yankee Nuclear Power Corporation Facility: Vermont Yankee Nuclear Power Station Location: Vernon, VT; Bolton, MA; and Region I Dates: April 7- May 21,1998 . !

Inspectors: George W. Morris, Senior Reactor Engineer i Larry E. Briggs, Senior Operations Engineer I Gregory V. Cranston, Reactor Engineer Brian T McDermott, Senior Resident inspector Jack Kudrick, Sr. Reactor Systems Engineer, NRR/DSSA/SCSB David Terao, Section Chief, NRR/DE/EMEB Approved by: William H. Ruland, Chief

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Electrical Engineering Branch

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Division of Reactor Safety l

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9007130358 900702 l PDR ADOCK 05000271 l G PDR

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EXECUTIVE SUMMARY Vermont Yankee Nuclear Power Station NRC Inspection Report No. 50 271/98-06 This inspection included aspects of licensee engineering and technical support operations as they pertained to the Basis for Maintaining Operation (BMO) process. The inspectors reviewed a selection of BMOs, some of which were expected to be closed prior to the end

- of the refueling outage and some that were expected to remain open following restart. No concerns were raised with regard to operability determinations, compensatory actions or corrective actions. However, as a result of this inspection, a violation of NRC regulations on deportability was identifie Enaineerina

The inspectors concluded, based on a limited review of the LOCA analysis at the Duke Engineering and Services offices, that the calculation adequately supported the initial torus temperature of 90 F. A more thorough review of the analysis will be performed by NRR in conjunction with the licensee's proposed change number 204 to the Technical Specifications. (Section E1.1)

• The inspectors concluded that the licensee had implemented their operability I assessment program in accordance with their procedures and BMO guideline. The inspectors review of a sample of the BMOs related to the outage work and restart j revealed no problem areas. (Section E2.1)

• The inspectors concluded that the licensee failed to recognize that the failure to notify the NRC when they (VY) identified that the EOPs would not safeguard the integrity of the containment barrier was a violation of the deportability requirements of 10 CFR 50.73. (Section E2.2)

• The inspectors concluded that the licensee had taken prompt and comprehensive corrective action where appropriate or the items were already discussed in other inspection reports. (Section E8.1)

• The inspectors concluded that the licensee's actions to resolve the BMOs identified in the licensee's May 1,1998 letter, as they pertain to restart of the plant, have been appropriate. Adequate controls are in place to ensum the mitigating factors are implemented prior to restart. (Section E8.2)

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TABLE OF CONTENTS PAGE EX EC UTI V E S U M M A RY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii El Conduct of Engine ering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 E LOCA Analysis ......................................... 's E2 Enginet. g Support of Facilities and Equipment ......................2 E2.1 Bases for Maintaining Operation (BMOs) . . . . . . . . . . . . . . . . . . . . . . . . 2 E2.2 Problem identification and Deportability ........................ 4 E8 Miscellaneous Engineering items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 E Previously ldentified Open items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 EB.2 BMOs Anticipated to Be Open at Startup . . . . . . . . . . . . . . . . . . . . . . . 6 V. Management Meetings ................. .. ...................... 7 X1 Exit Meeting Sum m ary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 PARTIAL LIST OF PERSONS CONTACTED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 IN SPECTIO N PilOCEDUR ES USED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 ITEM S O PEN E D, C LO S E D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 LI ST O F A C R O N Y M S U S E D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 iii t

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-) Report Details Backarott The plant was in an outage when this inspection period began and remained in the outage at the exit on May 21,1998. This special inspection was conducted primarily to review the licensee's Basis for Maintaining Operations (BMO) process. This is the licensee's operability determination process and included identification of the deficiencies, compensatory actions and corrective action E1 Conduct of Engineering i

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E LOCA Analysi j

! Insoection Scoot (92903)

The inspectors conducted a review at the Duke Er.gineering and Services (DE&S) i offices in Bolton, MA, to assess the methodology thm was used by DE&S personnel I for the re-analysis of the Large Break Loss of Coolant Accident ( LOCA) and Main ;

Steam Line Break (MSLB) Accident Scenarios for Vermont Yankee, This analysis l was documented in calculation No. VYC-1625, Rev. O, Torus Temperature and Pressure Response to Large Break LOCA and M3LB Accident Scenariu, dated l April 27,199 l

' ' Observations and Findinas Based on the limited review by the inspectors, the calculations appeared to be acceptable and appropriate for determining torus temperature and pressure response to large break LOCA and MSLB accident scenarios. The inspectors found that the sections of calculation No. VYC-1628 that were reviewed were both clear and concise in identifying the method and codes used. The inspectors confirmed that the latest calculation addressed previous problems, identified by the licensee and I the NRC, which were associated with the previous Technical Specification chang Qg.ntclypions r The inspectors concluded, based on the limited review, that the calculation adequately supported the initial torus temperature of 90 F and had no additional current concerns. A detailed review will be performed by NRR in conjunction with the licensee's proposed change number 204 to the Technical Specifications submitted by letter dated May 8,1998.

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E2 Engineering Support of Facilities and Equipment E Bases for Maintaining Operation (BMOs) insoection Scope (92903)

The lit:ensee had identified a significant number of operability questions primarily as a result of their Configuration improvement Program. The inspectors reviewed selected Bases for Maintaining Operation (BMOs) to assess the licensee's evaluation, compensatory actions and corrective actions for those selected BMO The inspectors selected 16 BMOs for review based on a sampling of those BMOs anticipated to be closed prior to startup and those that would probably remain open following startup from the outage. Five of the BMOs selected for review were items the licensee had expected would remain open following the outag The inspectors selected the following BMOs for review:

96-05 Torus Temperature TS 90-17 TIP Purgc Line Isolation 97-01 RBCCW Water Hammer inside the Drywell 97-13,97-16 Cable Separation 97-15 Torus Rupture Disc Design Basis 97-28 HPCI Suction / Appendix J 97-33 4 kV and 480 V Motor Protection 97-36 RHRSW Flow Signal 97-40 Fuse Ratings for DC Appli.:ations 97-50 RG 1.97 Category 1 & 2 Safety Classification l 97-51 DG Day Tank Level Control Valves 97-56 ACS Winter Operation 97-60 DG Cooling Following Manual Load Addition ,

98 01 HPCl/RCIC Water Hammer 98-05 RBCCW HELB Venerability The review included an identification and assessment of the following areas:

• Identification of what were the degraded conditions and an assessment if those conditions result in inoperability of required structures, systems or component * Identification of what were VY's design or !icensing basis for these item * An assessment of the compensatory measures and corrective actions for those BMOs that were closed and ths compensatory measures for those BWlOs that will remain open following restart from the outag i

• An assessment of whether those compensatory measures, especially those that may have required manual actions in lieu of autamatic or passive actions, constituted an unreviewed safety questio * An assessment of whether the controls in place to identify and resolve deficiencies in those BMOs were appropriate und timel ,

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In addition, the inspectors interviewed several licensed personnel to assess their knowledge and awareness of the outstanding BMO Observations and Findinas -

The inspectors did not find any problems with the Vermont Yankee BMO proces The inspectors found that the BMOs clearly identified the degraded or non- -

conforming conditions. The inspectors found that the compensatory actions or the

, corrective actions adequately addressed the conditions to maintain operabilit The inspectors found that the hcensed personnel interviewed were aware of the BMOs and their limited effect on current plant refue' ag operations. They were also

. aware that there would be several BMOs remaining open on restart and a listing of J currently open BM9s was updated daily and provided to the operations staff. The operators noted that operations management philosophy was to incorponte compensatory actions into plant procedures and thus minimize the use of extraneous instructions such as standing orders. This philosophy also served to minimize added burden on the operators. There were only two standing orders concerning BMOs at the time of the inspection, one dealt with the torus level and the other with torus and river temperatur The review of existing BMO 96-05, Torus Temperature Limits, showed conservative administrative limits had been initiated. However, the licensee was in the process of revising their LOCA analysis wlth Duke Engineering and Services (DE&S)

performing the technical analysis. NRR had met with the Vermont Yankee responsible engineers as well as the DE&S engineers on previous occasions at NRC

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Headquarters to discuss the progress of the ongoing DE&S reanalysis. The inspectors continued the inspection at the DE&S offices in Bolton, MA and met -

with the personnel who had perform the revised LOCA analysis (refer to Section E1.1 of this report).

Vermont Yankee plant management acknowledged that, prior to restart, they would f

re-review all the BMOs that would remain open after the outage to confirm the justification for keeping those BMOs open after startup, Conclusions The inspectors concluded that the licensee had implemented their operability assersment program in accordance with their procedures and BMO guideline. The inspectors review of a sample of the BMOs related to the outage work and restart revealed no problem areas. The degraded conditions were clearly identified and the  ;

compensatory and corrective actions were adequat i

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E2.2 Problem Identification and Deportability Insoection Scope (92903)

The inspectors reviewed the problem identification process to assess the extent of ,

management involvement in the screening, deportability assessment and evaluation I of identified concern b. .

Observations and Findinas

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The inspectors noted that concerns are raised at VY through their Event Report (ER)

process. The inspectors attended the morning event screening meeting where the -

ERs generated the previous day cre presented by the responsible department manager to the screening committee. The committee consisted of the department

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managers and was held in the plant managers office.Each ER was discussed, given a priority and assigned a department for evaluation and resolution. The inspectors observed that the threshold for initiating an ER appeared adequate. The committee -

also makes a screening for deportability. The licensee maintains one dedicated individual in.the Technical Support group to make the formal deportability screenings

= in accordance with their procedure AP0010, " Notifications and Reports Due".

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During the inspectors' review of the initiating ERs for the selected BMOs, the inspectors found an example of a failure to issue a Licensee Event. Report (LER). '

BMO 97-15 addrossed the torus rupture disc whose design bas!s was to function as a passive relief device to protect Vermont Yankee's Mark I cm inment. This device was in::talled in response to Generic Letter (GL) 8916, Installation of a Hardened Wetwell Vent," to improve the plant capability to mitigate the consequences of a complete loss of suppression pool cooling. The containment

. functions as one of the barriers for the release of radioactivity to the environmen Ti.e tolerance on the rupture disc burst pressure was 59 i 3 psig. The inspectors found that the licensee's screening for deportability as part of the review of Event Report 97-0273, dated March 20,1997, failed to consider that the response to a design basis accident using the existing emergency operating procedures, would

. lead to containment flood up, thereby pressurizing the containment, opening the 1 rupture disk, leading to possible liquid release through the wetwell ven in accordance with 10 CFR 50.73(a)(2)(C)(v), any condition [ including procedure errors] that alone could have prevented the fulfillment of the safety function of structures or systems that are required to control the release of radioactive material, must be reported through the LER process. This is a repeat violation of 10 CFR 50.73(a)(2), similar to that documented in inspection report 50-271/ 97-10 and the enforcement letter on this subject issued by the NRC on April 14,199 (VIO 50-271/98-06-01) (Note: VY issued LER 98-10 after the end of the inspection.) ~

The inspectors also found that the VY EOPs called for containment floodup in response to a large-break design basis LOCA. This action was found technically acceptable in general by NRC review and approval of the BWR Owner's Group i

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'(BWROG) emergency procedure guidelinas (EPG), revision 4 (see Thadani to Grace letter dated September 12,1988). The Office of Nuclear Reactor Regulation (NRR):

continues to review the latest revision to the BWROG EPG/ Severe Accident Guideline (SAG). As part of that review, NPR asked the BWROG to address the EP/ SAG transition criteria for containment floodup and venting. The inspectors will

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re-examine VY's transition criteria and final resolution of the rupture disk /wstwcll vent issue when NRR has finished their review. (IFl 50-271/98-06-03) .

Conclusions .

The inspectors concluded that the licensee failed to recognize that the failure to

~ notify the NRC when they (VY) identified that the EOPs would not safeguard the

~ integrity of.the containment barrier was a violation of the deportability requirements of 10 CFR 50.7 lE8 Miscellaneous Engineering items E8.1 - Previousiv Identified Open items L Insoection Scope-(92903)

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' Parallel with the _ inspection of the BMOs, the inspectors reviewed VY action on '

open items related to some of the initiating Event Reports (ERs), to determine if VY actions were acceptable, b.- ~ Observations and Findinas (Closed) IFl 97-02-08. Station service water / alternate coolina tower system eauivalencv. The licensee identified that technical specification (TS) 3.5.D.3 ..

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. allowed continued plant operation with both station service water (SW) subsystems inoperable for.up to seven days, provided that the alternate cooling tower subsystem (ACS) was available. The licensee identified that the ACS was not designed to the same standards as the SW system and placed immediate administrative controls limiting plant operation with both SW subsystems inoperable. The licensee initiated a TS change request to revise TS 3.5.D.3

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accordingly. The inspectors found this resolution acceptable and this item was close ' (Clor.ed) IFl 97-04-03. DG ootential common mode failure. The NRC Architect / -

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. Engineer design inspection team identified a common mode vulnerability of the air-U controlled diesel generator cooling watar control valves and documented this same -

concern in inspection report 97-201, unresolved item (URI) 97-201-18. The

resident inspectors confirmed the immediate corrective action by the li

:ensee to L replace the commercial pressure regulators in the air control lines with dedicated L . regulators. The URI was closed in inspection report 97-10 and replaced with -

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L' escalated enforcement item eel 97-10-01f. Following an enforcement conference with the utility conducted on March 2,1998, a notice of violation was issued on

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April 14; 1998. As a result of the related enforce'nent items, the inspectors closed L

this duplicate inspection followup ite l

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LUodated) URI 97-10-14. Delaved access oower supolv, VY had taken credit for the l Vernon tie-line as both the delayed offsite power source and the station blackout j (SBO) alternate ac (AAC) power source. The inspectors verified the addition of a no-load disconnect switch during refueling outage RFO-20. This modification permits using the backfeed through the main transformer as the delayed offsite power supply, allowing the Vernon tie-line to serve only as the SBO AAC sourc The item remains open pending NRC disposition of any possible enforcement actio ' Conclusions The inspectors concluded that the licensee had taken prompt and comprehensive i corrective action where appropriat E8.2 BMOs Anticipated to Be Open at Stortuo i Insoection Scope (92903)

i On May 1,1998, the licenece submitted a letter to the NRC describing the results of an integrated assessment of BMOs which, at that time, were expected to be open at the conclusion of the 1998 refueling outage. The letter also provided a summary of each BMO, the status of corrective actions, and the licensee's schedule to completion the corrective actions. The inspectors performed an in-office review of the May 1,1998, letter to assess potential impacts on the operability of safety-related equipment, the potential burdens assoc lated with compensatory measures, and the licensee's plans tc resolve the issues. In addition, selected mitigating factors were verified through document reviews, interviews with licensee personnel, and field observation Observations and Findinos The licensee's letter identified 10 BMOs that were expected to remain open following the 1998 refueling outage. Four of the BMOs (96-05,97-01,97-50, 97-51) were evaluated during the onsite inspection. The inspectors review did not identify any substantive differences between the issues inspected and the information presented in the BMO lette The inspectors' review of select mitigating factors found that many of the actions were still under development as of May 19,1998. Examples included the matrix of alternate indication for the RG 1.97 issues (BMOs 97-50 and 98-10), revision of the environmental qualification documentation for torus temperature concerns, (BMO 96-05), development d snhanced inspections for EDG weld issues (BMO 97-39),

and a revision of the integrated assessmtat of the BMOs which will be open at restart. No problems were identified with the licensee's plans, and the individual actions required for startup (and long term) have been entered in VY's commitment tracking syste _ _ -___-_-_ ____ _ -______ _ _ _ _ _ _ _ >

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i 1 Conclusions , l A letter from Vermont Yankee to the NRC, dated May 1,1998, was reviewed and found to be consistent with inspection findings for BMOs that will remain open following the spring 1998 refueling outage. With completion and implementation of the mitigating factors described in the letter, the inspectors concluded that the licensee's actions to resolve the 10 BMOs, as they pertain to restart of the plant, have been appropriate. Adequato controls are in place to ensure the mitigating factors are implemented prior to restar ;

V. Manaaement Meetinas ,

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X1 Exit Meating Summary

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A meeting was held on April 24,1998, with Mr Reid, Mr. Maret, and others on the VY staff to discuss the purpose and findings of this inspection. At that time, the inspectors identified and reviewed the violation cited in this repor An exit was held on May 21,1998, with Mr. Leach, Mr. Maret and others on the VY staff to review the results of the inspection, including the violation cited in this

. report, the NRR/ Region i visit to the Duke Engineering and Services Company to discuss the torus temperature issue and its relation to BMO 96-05 and the Region I review of their May 1,1998, BMO integrated assessment.

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PARTIAL LIST OF PERSbNS CONTACTED M. Balduzzi Operations Superintendent

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T. Byrne Licensing Engineer D. Colsyn Technical Support Manager J. DeVincentit Assistant to Engineering Director J. Hoffman DE&S, Manager, Accident Analysis Group R. January Electrical and l&C Design Engineering Manager D. Leach VP, Engineering E. Lindamood Director of Engineering D. McElwee Liaison Engineer G. Maret Plant Manager D. Reid Sr. VP, Operations F. Sabadini DE&S, Quality Assurance G. Sen Licensing Manager W. Sherman State of Vermont, Department of Public Services i

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INSPECTION PROCEDURES USED 92903 Followup - Engineering ITEMS OPENED, CLOSED Opened 50-271/98-06-01 VIO Failure to issue an LER 50-271/98-06-02 IFl EPG/ SAG Transition Criteria for Containment Floodup Closed 50-271/97-02-08 IFl ACS Cooling Tower 50-271/97-04-03 IFl DG Potential Common Mode Failure Uodated 50-271/97-10 14 URI Delayed Access Power Supply i

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l UST OF ACRONYMS USED AEC Atomic Energy Commission ACS Alternate Cooling Source BMO Basis for Maintain Operation CFR Code of Federal Regulations DC Direct Current DE&S Duke Engineering and Services DG Diesel Generator eel Escalated Enforcement item ER Event Report j FSAR Final Safety Analysis Report i GDC General Design Criteria ,

HELB High Energy Line Break l HPCI High Pressure Coolant injection IFl inspector Followup Item  ;

KV kilovolt I LCO Limited Condition for Operation LER Licensee Event Report  !

LOCA Loss of Coolant Accident NCV Non-Cited Violation NRC Nuclear Regulatory Commission NRR Nuclear Reactor Regulation RBCCW Reactor Building Closed Cooling Water RCIC Reactor Core Isolation Cooling RFO Refueling Outage RG Regulatory Guide RHRSW Residual Heat Removal Service Water SW Service Water '

TIP Trans Incore Probe TS Technical Specification URI Unresolved item VIO Violation VY Vermont Yankee L_ __________ ____---_---- _------ .- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -