ML20236Q883

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Insp Rept 50-271/98-80 on 980518-0605.Violations Noted.Major Areas Inspected:Aspects of Licensee Engineering & Technical Support Operations as They Pertain to C/A Program,Se & Core Engineering Programs & Processes
ML20236Q883
Person / Time
Site: Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date: 07/16/1998
From:
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20236Q872 List:
References
50-271-98-80, NUDOCS 9807210103
Download: ML20236Q883 (34)


See also: IR 05000271/1998080

Text

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U.S. NUCLEAR REGULATORY COMMISSION

REGION I

Docket No:

50-271

License No:

DAR-28

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Report No:

50-271/98-80

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Licensee:

Vermont Yankee Nuclear Power Corporation

Facility:

Vermont Yankee Nuclear Power Station

Location:

Vernon, VT and Region 1

Dates:

May 18 - June 5,1998

Inspectors:

George W. Morris, Senior Reactor Engineer

Brian T. McDermott, Senior Resident inspector

Gregory V. Cranston, Reactor Engineer

Keith A. Young, Reactor Engineer

Approved by:

William H. Ruland, Chief

Electrical Engineering Branch

Division of Reactor Safety

9907210103 990716

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PDR

ADOCK 05000271

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PDR

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EXECUTIVE SUMMARY

Vermont Yankee Nuclear Power Station

NRC Inspection Report No. 50-271/98-80

This combined core engineering inspection included aspects of licensee engineering and

technical support operations as they pertained to the corrective action program, safety

evaluation and core engineering programs and processes. As a result of this inspection,

five violations of NRC regulations were identified.

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Maintenance

The only medium voltage cable preventive maintenance that VY presently performed

was associated with the insulation resistance testing of the connected loads and

was consistent with general industry practice. (Section M2.1)

The licensee's initiative to establish periodic cable testing of the medium voltage

cables from the AUX and SUT transformers would be appropriate in light of two

cable failures in five years. (Section M2.1)

The licensee's informal handling of the cable vendor's failure analysis of the failed

cable from startup transformer T-3-8 to Bus 2 did not properly control the vendor-

supplied service. (Section M2.1)

Enaineerina

The licensee's safety evaluation for the 1974 HPCl/RCIC Vacuum Breaker

Modification (EDCR 73-32) incorrectly stated that the modification did not create an

unreviewed safety question. This old design issue was a violation of 10 CFR 50.59

but was not cited in accordance with Enforcement Policy Vll.B.3. (Section E1.1)

The licensee's safety evaluation for the control room HVAC temporary modification

and procedure change failed to address the impact of required operator actions and

was a violation of 10 CFR 50.59. (Sections E1,1 and E2.4)

Personnel responsible for the commercial grade dedication program were

knowledgeable of the program and appeared to be implementing the program

properly. (Section E1.2)

Modification EDCR 97-414, AOG Modifications, was acceptable with sufficient

documentation and justifications, adequate installation instructions, and adequate

post modification testing to ensure operability. The team also concluded that the

program for designing and installing configuration changes to plant systems was

adequate and the 50.59 program was properly applied in this case. (Section E2.1)

Modification EDCR 98-402, HPCl/RCIC Vacuum Breakers, resolved the technical

issue associated with water hammer problems and installed a design that is

consistent with other utilities and with General Electric recommendations.

(Section E2.1)

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The configuration control documentation for the proposed changes to the FSAR and

DBD associated with the HPCl/RCIC Vacuum Breaker modification EDCR 98-402 did

not describe all key aspects of the design change but would be subject to further

licensee review as part of the change process for those documents and was

acceptable. (Section E2.1)

The Minor Modification procedure was appropriately being used to make minor

design changes. The Equivalency Evaluation procedure provides for a detailed

assessment of alternate replacement items and this process was properly

implemented for the items sampled. (Section E2.2)

The licensee was working off their TM backlog and had a procedure in place to

minimize future TM's. PORC review of the overdue TMs was also evidenced and

the team concluded sufficient managernent attention was being given to TMs.

(Section E2.3)

Corrective actions for the control room i entilation system temporary modification, if

the nonsafety-related instrument air supply was lost, were inadequate in that no

operability determination was performed in accordance with administrative

procedures and the root cause determination failed to identify that the components

were previously overlooked during engineering reviews performed in response to

NRC Generic Letter 88-14, a violation of Appendix B, Criterion XVI. (Section E2.4

and E5.2)

The licensee failed to report the control room HVAC design deficiency as required

by10 CFR 50.73 and a violation was issued. (Sections E2.4 and E5.1)

The DBD program was concentrating on the most risk significant systems artd this

program was an essential part of the transition of design engineering responsibility

to VY. (Section E3.1)

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The licensee's failure to maintain control of the new design basis documents

resulted in a violation against Appendix B, Criterion Ill, Design Control. (Section

E3.1)

The Event Report (ER) process provided sufficient information to support the early

identification of emerging problems to licensee management. ER screening

meetings contributed the perspectives of all departments to ER disposition plans.

(Section E4.1)

Trend report frequency (annual) and corrective action for recurring problems areas

were being evaluated by the licensee as part of AP-OO28 commitments. (Section

E4.1)

The documentation of initial operability determinations was not always consistent

with procedural guidance. (Section E4.1)

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The licensee issued a late LER for the HPCl/RCIC vacuum breaker, a violation of

50 73. This item was similar to the violation recently issued with inspection Report

50 271/97-10. This deportability issue was not cited in accordance with

Enforcement Policy Vll.B.1 (Section E5.1)

The licensee's control of vendor supplied services for the steam relief valve

setpoints was weak. (Section E5.2)

The licensee's conservative approach for containment pressure, using an analysis

from a similar plant with key VY values incorporated, provided reasonable assurance

that the plant could startup and operate safely. An inspector follow up item was

opened pending reviaw by the NRC of the VY specific analysis. (Section E5.2)

The Design Engineering organization and the transfer of design responsibility to the

site continued to be progressing without any observed problems that would affect

plant safety. (Section E6.1)

The VY Systems Engineering organization continued to show progress in

implementing its mission consistent with the industry expectations for system

engineers. The system engineers' notebooks and system health reports reviewed

by the team were consistent with those goals. (Section E6.2)

A change to the Quality Assurance Program that reduced previous commitments

was implemented prior to NRC approval and was a violation of 10 CFR 50.54.

(Section E7.1)

The licensee did not address the potentialimpact on plant equipment and a

continued implementation of the unapproved standard. This indicated a weakness

in implementation of the corrective action process. An unresolved item was opened

pending the completion of the NRC's review of a related licensee submittal.

(Section E7.1)

The QA program instituted at VY to provide oversight of the functional area

assessments was acceptable and use of the self assessment program was effective.

(Section E7.2)

The station service transformer, bus 9 rating and bus 9 feeder breaker overcurrent

relay setting had sufficient margin available to permit the testing of the fire pump

under all operating conditions. (Section E8.1)

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TABLE OF CONTENTS

PAGE

EX EC UTIVE S U M M A RY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

11. M a i nt e n a n c e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

M2

Maintenance Support of Facilities and Equipment ................. 1

M2.1 C a ble Te st Prog ram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

111. E n gi n e ering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

El

Conduct o f Engineering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

' E1.1

Sa f ety Evaluations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

E1.2 Commercial Grade Dedication

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E2

Engineering Support of Facilities and Equipment ..................5

E2.1

M odific atio ns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

E2.2 Minor Modifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

E2.3 Temporary Modifications

.............................8

E2.4 Control Room Ventilation (CRV) Temporary Modification 96-043 .. 9

E3

Engineering Procedures and Documentation . . . . . . . . . . . . . . . . . . . . 12

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E3.1

Configuration Control Program . . . . . . . . . . . . . . . . . . . . . . . . . 12

E4

Engineering Staff Knowledge and Performance . . . . . . . . . . . . . . . . . . 13

E4.1

Corrective Action Program . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

ES

Engineering Staff Training and Performance

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E5.1

R e port a bility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 5

E5.2 Operability Determinations ...........................16

E6

Engineering Organization and Administration . . . . . . . . . . . . . . . . . . . . 18

E6.1

De sign Engineering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

E6.2 Systems Engineering

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E7

Quality Assurance in Engineering Activities . . . . . . . . . . . . . . . . . . . . . 19

E7.1

Quality Assurance Program Change . . . . . . . . . . . . . . . . . . . . . 19

E7.2 Self Assessments

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E8

Miscellaneous Engineering issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

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E8.1

Loading on Safety Bus Number 9 . . . . . . . . . . . . . . . . . . . . . . . 22

E8.2 Licensee Event Reports

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E8.3 Previously Reviewed items . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

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(Closed) VIO 50-271/97-10-07 . . . . . . . . . . . . . . . . . . . . . . . . 24

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(Closed) VIO 9 7 -0 6-0 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 4

(Closed) IFl 50-2 71/9 6-200-01 . . . . . . . . . . . . . . . . . . . . . . . . 24

V. Managem e nt Meeting s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 5

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Exit Meeting Summ ary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 5

PARTIAL LIST OF PERSONS CONTACTED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

INSPECTION PROCEDURES USED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

ITEMS OPENED, CLOSED and DISCUSSED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

LIST OF AC RO NYM S USED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 8

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Report Details

Summary of Plant Status

At the beginning of this inspection, Vermont Yankee (VY) was in the middle of a planned

maintenance and refueling outage,

ll. Maintenance

M2

Maintenance Support of Facilities and Equipment

M 2.1 Cable Test Proaram (92903)

a.

Insoection Scope

The team reviewed Vermont Yankee's cable test program for medium voltage cable

to determine its approach to cable preventive maintenance in light of the recent

intermittent ground on one cable. This included review of event reports (ERs), of

maintenance and surveillance procedures, cable problems, cable test results,

equivalency evaluations and interviews with licensee personnel.

b.

Observations and Findinas

The team reviewed procedure OP 0023, " Installation and Testing of Cable and

Conduit," Revision 8, which provides a generic installation and test procedure for

cable and conduit specified in engineering design change requests (EDCRs), minor

modifications (mms), temporary modifications (TMs), and/or maintenance planning

and control (MPAC) work orders. Through review of the above procedure and

discussions with licensee personnel, the team determined that the only cable

preventive maintenance (with limited exception of some trend data gathered in

1995 following a 1993 cable failure) the licensee had performed was associated

with de insulation testing of the connected loads (OP-5235, AC and DC Motor

Maintenance.) The team found that, with the exception of initial post-installation

high potential tests and troubleshooting, no preventive maintenance (PM) testing of

medium voltage cable was performed while disconnected from the supplied load.

The team also reviewed procedure OP 4142, "Vernon Tie and Delayed Access

Power Source Backfeed Surveillance," Revision 7, and the results of that

surveillance to determine what testing was accomplished for cables at Vermont

Yankee. The surveillance for the Vernon tie testing was accomplished May 25,

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1998, during refueling outage (RFO) 20. The team found that the Vernon tie was

tested by loading it to within the acceptance criteria of 2210 kW to 2762 kW for at

least one hour at nominal operating voltage. The team found that no separate PM

testing of the cable itself was required by this surveillance procedure nor performed

by the licensee.

The team reviewed ER 97-1655 which documented an intermittent ground on the

non-safety related medium voltage cable between the start-up transformer (SUT) T-

3-B and Bus 2. (The medium voltage cables from the SUT and the auxiliary

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. transformer are composed of multiple single phase conductors from the

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transformers, through underground duct banks, to the 4160 Volt Buses 1 and 2.)

The licensee identified and replaced the defective conductor in the affected circuit

and identified and replaced another deteriorated conductor in the redundant

transformer T-3 B circuit as part of its extent-of-condition review. As part of the

long term corrective action associated with this ER, the licensee initiated a

commitment, under the AP 0028 Commitment Tracking process, to establish a

preventive maintenance program for the cables from the auxiliary (AUX) and

startup transformers on a refueling outage basis.

The team was informed by the licensee that it sent a sample of the failed cable,

found in response to ER 97-1655, to the new cable vendor's laboratory for failure

analysis. This failure analysis was not docomented in any formal agreement with

the vendor therefore it was not clear how the results would support the licensee's

corrective action program. The results of the cable failure analyt.:is were not

available from the cable vendor at the conclusion of this inspection.

c.

Conclusions

The team concluded that the only medium voltage cable preventive maintenance

that VY presently performed was associated with the insulation resistance testing

of the connected loads. This was consistent with industry practice, and did not

violate any NRC regulation. The team concluded that the licensee's initiative to

establish periodic cable testing of the medium volvage cables from the AUX and

SUT transformers would be appropiate in light of two cable failures in five years and

was consirtent with NRC's expectations for adequMe corrective action.

While the team concluded that the licensee's informal handling of the cable

vendor's failure analysis of the failed cable from startup transformer T-3-B to Bus 2

would not have satisfied quality assurance program requirements for control the

vendor-supplied service, since the cable involved was not safety-related, no

violation was identified.

Ill. Enaineerina

E1

Conduct of Engineering

E1.1

Safety Evaluations (370011

a.

Scope of Inspection

The team reviewed the licensee's procedural guidance for the safety evaluation

program to assess that program against the latest guidance contained in NRC

Inspection Manual Chapter 9900 and regulatory requirements of 10 CFR 50.59.

The team reviewed selected safety screenings and safety evaluations the licensee

performed for design changes and procedure revisions.

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b.

Observations and Findi al

D

BPCl/RCIC Vacuum Breakers

As noted in Section E2.1 of this report, the team's review of modification EDCR 98-

402, HPCl/RCIC Vacuum Breakers, found that the licensee's safety evaluation

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adequately described that the check valves would be Type C tested in accordance

with the 10CRF 50, Appendix J, localleakage rate testing program.

However, as part of that review, the team also reviewed EDCR 73-32 HPCl/RCIC

Vacuum Breakers, which originally installed the vacuum breakers in the turbine

exhaust lines between the torus and the containment isolation check valves. The

team determined that the licensee's review of modification EDCR 73 32, HPCl/RCIC

Vacuum Breakers, and associated safety evaluation, failed to address all relevant

water hammer issues, in that a new water hammer potential on turbine restart,

resulting from the design change, created a possibility for an accident or

malfunction of a different type than any evaluated previously in the safety analysis

report.

10 CFR 50.59 states a proposed change, test, or experiment shall be deemed to

involve an unroviewed safety question (l) if the probability of occurrence or the

consequences of an accident or malfunction of equipment important to safety

previously evaluated in the safety analysis report may be increased; or (ii) if a

possibility for an accident or malfunction of a different type than any evaluated

previously in the safety analysis report may be created; or (iii) if the margin of

safety as defined in the basis for any technical specification is resced.

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The licensee's failure to address the creation of the second water hammer event in

EDCR 73-32 (creating possibility for an accident or malfunction of a different type

than any evaluated previously in the safety analysis report) resulted in an

incomplete safety evaluation and an unreviewed safety question. This was a

violation of 10CFR 50.59. However, this item was licensee-identified during its

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validation of the HPCl/RCIC design basis document initiative. The immediate and

long-term corrective actions were comprehensive and performed within a reasonable

time frame. (Refer to Section E2.1 of this report.) The issue also was not likely to

be identified by routine licensee activities. Therefore, in accordance with the NRC's

Enforcement Policy Vll.B.3, involving old design issues, this violation was not cited.

(NCV 50 271/98-80-09)

Control Room HVAC

As noted in Section E2.4 of this report, the licensee discovered, in 1996, that the

Control Room HVAC would not function as expected on the loss of nonsafety-

related instrument air. Although a temporary modification (TM 96-043) was

processed and procedures were revised to help mitigate the degraded condition, the

team found that the safety evaluation for the TM failed to address the impact of

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required operator actions.

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c .'

Conclusions

The team concluded that the licensee provided an adequate safety evaluation for

the HPCl/RCIC Vacuum Breaker modification (EDCR 98-402).

The team concluded that the licensee's safety evaluation for the 1974 HPCl/RCIC

Vacuum Breaker Modification (EDCR 73-32) incorrectly stated that the modification

did not create an unreviewed safety question. -This old design issue was a violation

of 10 CFR 50.59 but was not cited in accordance with Enforcement Policy Vll.B.3.

The team concluded that the licensee's safety evaluation for the control room

HVAC temporary modification failed to address the impact of required operator

actions and was a violation of 10 CFR 50.59 as noted in Section E2.4 of this

report.

E1.2 Commercial Grade Dedication (37550)

a.

Inspection Scope (37550)

The team reviewed the engineering involvement in the evaluation of components

used in safety-related systems commercial grade. The team conducted discussions

with Procurement Engineering personnel responsible for commercial grade

dedication (CGD) to assess their knowledge of the program.

In addition, the team reviewed Temporary Modification 94-019 (which installed air

isolation valves on the EDG starting air system) and documentation associated with

a CGD purchase of replacement parts (rupture discs) for the control rod drive

hydraulic control units to assess the licensee's conformance to its program

requirements.

b.

Observations and Findinas

!

The team found that the analyses and reviews for the commercial grade dedication

for the isolation valves and rupture discs were appropriate.

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Conclusions

Personnel responsible for the CGD program were knowledgeable of the program and

appeared to be implementing the program properly.

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E2

Engineering Support of Facilities and Equipment

E2.1

Modifications (37550)

a.

Inspection Scope (37550)

The team reviewed engineering design change requests focusing on the design

change program implementation and the licensee's review of the plant configuration

changes to ensure that the criteria outlined in 10 CFR 50.59 and 10 CFR,

Appendix 8, " Design Control," were met. Specific items reviewed were: related

FSAR sections, safety evaluations, drawing modifications, post-modification

testing, and acceptance criteria,

b.

Observations and Findinas

Advanced Off-Gas (AOG) System

The team reviewed EDCR 97-414, AOG Modifications, approved February 3,1998,

to determine the extent and the adequacy of this modification. This modification

was implemented during RFO 20. The scope of the modification included

reconfiguration of control room panel (CRP) 9-50 to provide separation of the "A",

"B", and common trains' components, replacement of 24 VDC supplies, and several

other component replacements. The team found that the EDCR was of acceptable

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quality with sufficient documentation to permit evaluation of the effect of this

change on the design and licensing basis. The package also included necessary

procedure changes, drawing changes, adequate installation instructions, and

appropriate retest instructions. The team verified the installation and changes made

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during a walk down of CRP 9-50. The team noted that part of this modification

was to ensure that no crossed neutral wires existed in the AOG panel. The team

6etermined that acceptable post modification testing was conducted to ensure no

crossed neutral wires existed and that the installed condition was per the drawings.

Through discussions with licensee personnel, the team determined that the AOG

system was energized as the plant was returned to power operation after RFO 20.

As of the exit date of this inspection, no AOG concerns were identified.

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HPCl/RCIC Vacuum Breakers

The team reviewed EDCR 98-402, HPCl/RCIC Vacuum Breake's, which modified the

existing vacuum breakers on the HPCl and RCIC turbina exhaust lines to take

suction from the torus atmosphere rather than from the reactor building Standby

Gas Treatment System. This review included a walkdown of the new installation

from the suppression pool penetration to the HPCI and RCIC containment isolation

valves. The Safety Evaluation (50.59) for the modification and the proposed

. changes M update the FSAR and the draft Design Basis Documents (DBD) for HPCI

and RCnl aere also reviewed. (Previously there was no discussion of the vacuum

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breakers in the FSAR.) The team reviewed the sizing calculations for the vacuum

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breaker lines for HPCI and RCIC. The team noted that the licensee had prepared a

Basis for Maintaining Operation, BMO 98-01, HPCl/RC!C Water Hammer, which

addressed the team's water hammer concerns.

Additionally, based on a review of the proposed changes to the FSAR and the draft

DBDs, associated with modification EDCR 98-402, the team observed that the

proposed changes to those documents did not adequately describe the design bases

for the HPCI or RCIC vacuum breakers / pressure equalizing lines although the

proposed changes to the FSAR figures for HPCI and RCIC adequately incorporate

the change. Also, the Training Module for that design change did not completely

describe the bases for the change. The licensee indicated the proposed changes to

the FSAR and the DBD would be further reviewed as part of their respective change

processes.

The team's review of FSAR Chapter 14, Accident Analysis, found that it was silent

regarding starting and stopping the turbine, which could result in water hammer.

The team also reviewed EDCR 73-32, HPCl/RCIC Vacuum Breakers, which installed

the vacuum breakers in the turbine exhaust lines between the torus and the

containment isolation check valves. This modification was not described in the

FSAR.

The team determined that the licensee's review of modification EDCR 73-32,

HPCl/RCIC Vacuum Breakers, and associated safety evaluation, failed to address all

relevant water hammer issues, in that the new water hammer potential on turbine

restart, resulting from the design change, created a possibility for an accident or

malfunction of a different type than any evaluated previously in the safety analysis

report. However, the 50.59 safety evaluation failed to conclude that the restart

-water hammer was an unreviewed safety question requiring NRC approval prior to

implementing the design change. This was a violation of 10 CFR 50.59. (Refer to

Section E1.1 of this report.)

The team also reviewed other modifications that may have been done on the

HPCI and RCIC systems that could have been affected by EDCR 73-32 and

the associated lack of description of the vacuum breaker systems in the

FSAR. Also the team walked down the HPCI and RCIC syctems between the

torus and the containment isolation to verify that the configuration including

the new design change (EDCR 98-402) was consistent with the existing

controlled P&lD's and confirmed that the mark-ups reflecting the changes

associated with EDCR 98-402 were correct. No concerns or discrepancies

were found.

c.

Conclusions

The team concluded that modification EDCR 97-414 was acceptable with sufficient

documentation and justifications, adequate installation instructions, and adequate

post modification testing to ensure operability. The team also concluded that the

o

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program for designing and installing configuration changes to plant systerns was

adequate and the 10 CFR 50.59 program was properly applied in this case.

The team concluded that modification EDCR 98-402 resolved the technical issue

associated with water hammer problems and installed a design that was consistent

with other utilities and with General Electric SIL No. 30. The proposed changes for

the FSAR and DBD associated with modification EDCR 98-402 package did not

describe all key aspects of the design change but would be subject to further

licensee review and was acceptable.

The team concluded that the licensee's previous design change, EDCR 73-

32, and the associated safety evaluation, constituted an unreviewed safety

question and was subject to enforcement discretion as an old design issue.

The team concluded that based on a review of previous modifications

associated with the vacuum breaker system for the HPCI and RCIC turbine

exhaast lines by a walkdown of the system that there was reasonable

assurance that there was no other adverse impact to plant safety due to

other modifications or due to lack of a description of the vacuum breaker

system in the FSAR.

E2.2 Minor Modifications (37550)

a.

Inspection Scope (37550)

The team reviewed the Minor Modification Procedure, AP-OO20, Control Of

Temporary and Minor Modifications and Minor Modifications (MM)97-059,97-073

and 98-015, to assess the licensee's categorization of minor mods and the

implementation of its program. Procedure AP-0842, Equivalency Evaluation, and

Equivalency Evaluation Worksheets #.581, #582, and #838, were also reviewed to

assess the licensee's process for verifying alternate replacement items can be

installed without a plant design change.

b.

Observations and Findinas

The team observed that the MM proradure has specific requirements and guidelines

regarding what qualifies as a minor modification (MM). The MM procedure can be

used to efficiently and effectively install minor modifications permanently without

the additional procedural steps required to install an EDCR. The procedure also

includes the method to install temporary modifications (TM), how long a TM should

be in place, and periodic review requirements of existing TMs. As noted below, the

team noted that there are existing TM's in place that could be converted, essentially

as is, into permanent installations using the MM process but are still being carried

as temporary modifications and have been so for well over the recommended time

limit of six months.

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8

The equivalency enluation process provides a means to verify that any physical or

functional differences in the replacement item are better than, or equal to, the

original item. The evaluation procedure addresses critical design characteristics;

interrelated plant components, systems, and structures; plant technical programs;

preventive maintenance; simulator fidelity; operating procedures; and design

calculations and configuration control databases. The inspector noted that in all

cases, other than administrative changes, a 50.59(a)(1) screening evaluation must

be completed in accordance with AP-6002.

The team's review of the selected minor modifications indicated the licensee was

conforming to its guidance procedures. No technical questions were raised by the

team on the minor modifications or equivalency evaluation worksheets reviewed.

c.

Conclusion _

The team concluded that the Minor Modification procedure was appropriately being

used to make minor design changes. The Equivalency Evaluation procedure

provides for a detsited assessment of alternate replacement items and this process

was properly implemented for the items sampled.

E2.3 Temocrary Modifications (37550)

a.

insoection Scope (37550)

The team reviewed Temporary Modification (TM) Procedure, AP-0020, Control Of

Temporary and Minor Modifications, to assess the licensee's control of TM's. Three

TMs were reviewed by the team to assess the licensee's implementation of the

program: TM 92-18, which installed vent valves on Pumps P-49-1 A & 18; TM 94-

019, which installed two manual ball valves on the EDG starting air system; and

TM 96-043, which replaced the actuator for a control room cooling valve and added

restraints for manual operation of control room fan dampers.

I

b.

Observations and Findinas

The Temporary Modification (TM) procedure has specific requirements and

guidelines regarding what qualifies as a TM, how long a TM should be in place, and

periodic review requirements of existing TMs.

TM 92-18, which installed vent valves on Pumps P-49-1 A and 18, had been in

place more than six years and was revised under the current procedure in January

1998. Acccrding to the current procedure TM 92-18 would not qualify as a TM

and should be installed permanently using the Minor Modification (MM) process,

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Additionally, the procedure states that a TM should not be installed for more than 6

months. Therefore, rather than revising the TM, a MM should have been generated.

For this situation, where a procedure change impacts existing TMs, VY has not

provided guidance on how existing TM's should be handled and whether ' grand

fathering' applied when new or revised procedures were issued.

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TM 94-019, which installed two manual ball valves on the EDG starting air system,

had been in place for more than three years. This TM was made permanent during

the recent 1998 refueling outage per EDCR 97-401 which required commercial

grade dedication of the valves. The team found that appropriate analyses and

reviews were completed in conjunction with superseding TM 94-019 with

permanent modification EDCR 97-401.

TM 96-043 modified the control room ventilation system to compensate for two

design deficiencies. Several concerns were identified regarding this issue and they

are discussed in detailin Section E2.4 of this report.

The team observed that those temporary modifications that had been installed more

than six months were walked down by the responsible department and engineering.

The results of the walkdowns were also presented to PORC for its review and

approval of future plans with the TMs. In addition, the licensee was working off the

backlog of overdue TMs.

c.

Conclusion

The team concluded that the licensee was working off its TM backlog and had a

procedure in place to minimize future TM's. PORC review of the overdue TMs was

also evidenced and the team concluded sufficient management attention was being

given to TMs. However, the team concluded that the licensee had missed

opportunities to use the current procedure to remove additional TM's by extending

an existing TM rather then making the modification permtnent using the MM

procedure.

E2.4 Control Room Ventilation (CRV) Temocrary Modification 96-043

a.

Inspection Scope (37550. 37001)

Temporary Modification (TM)96-043 was selected for review to assess the TM

process, its implementation, the quality of supporting engineering evaluations, and

the functionalimpacts of the change. This TM was selected for review based on its

age and its potentialimpact on control room aquipmcat.

b.

Observations and Findinas

The VY FSAR Section 10.12.3.3 describes the main contro1 room ventilating system

which is designed to provide summer air conditioning and winter heating. The

FSAR states, "A remote manual switch located in the main control room permits

closure af the outside air damper, control room kitchen and bathroom exhaust

dampers,' and computer room supply damper, in order to isolate the control room

, during an accident." Operator response to high unexpected or unexplained radiation

levels is directed by off normal procedure ON-3153, Excessive Radiation Levels.

Step 11 of ON-3153, directs operators to place the CRV recirculation mode switch

to the emergency position. This action accomplishes the isolation described by the

FSAR. The CRV system is support equipment necessary to maintain temperatures

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within the requirements for safety-related equipment in the control room and it has

been classified by VY as a safety class three system.

The team observed that the licensee identified on August 19,1996, that control

room chilled water control valve would fait closed on the loss of nonsafety-related

instrument air. The initial ER 96-0550 documentation noted that there was a two

to four hour time delay before significant temperature increases in the control room

would occur. The ER also indicated that an operability determination (i.e., BMO)

was required within 30 days based on the system's safety classification. The team

found that the ER deportability review had indicated that no reports to the NRC were

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required.

The inspectors' review of the TM 96-043 package found that the licensee had

identified a second deficiency associated with the CRV. Dampers associated with

the suction and discharge of the two CRV fans will fail closed on loss of nonsafety-

related instrument air, isolating the air flow to the control room. The temporary

modification included a valve actuator design change, mechanical restraints to

secure the fan dampers open, and procedure changes to implement the manual

actions outside the control room, if necessary. Because the manual actions required

by the operators would expose them to higher radiation levels than if they would

remain in the contro: .u n., Go consequences of an accident may be increased.

10 CFR 50.59, Changes, tests and experiments, specifies that the licensee may

make changes to its facility and procedures as described in the safety analysis

report and conduct tests or experiments not described in the safety analysis report

without prior Commission approval, provided the change does not involve a change

in the technical specifications or an unreviewed safety question (USO); and requires

the licensee to maintain records of changes in the facility, including written safety

evaluations providing the bases for the determination that the change does not

involve an USO.

The inspector found that the safety evaluation, dated October 8,1996, did not

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address the potential consequences of the compensatory operator actions.

Although the system would not operate as described in the FSAR after the TM

installation, the safety evaluation states "This TM brings the control room HVAC

j

system into compliance with its intended function." Therefore there was not a

I

sufficient basis to conclude that the change did not increase the consequences to

the control room operator. The inspector also noted that the safety evaluation

appeared to be a justification for the TM as a change to the original design of the

facility, rather than an evaluation of the temporary modification itself. This concept

is discussed in Section 4.7 of NRC Inspection Manual 9900, Resolution of Degraded

and Nonconforming Conditions.

The guidance states, "If an interim compensatory action is taken to address the

condition and involves a procedure change or temporary modification, a 10 CFR 50.59 review should be conducted and may result in a safety evaluation. The

intent is to determine whether the compensatory action itself (not the degraded

condition) impacts other aspects of the facility described in the SAR."

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Ti.u licensee's f ailure to perform an adequate safety evaluation for the procedure

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changes and temporary modification associated with the control room ventilation

system was a violatic.) of 10 CFR 50.59. (VIO 50-271/98-80-01)

Other aspects of the licensee's corrective action for this Nonconforming condition

were also found to be inadequate. The team found that the licensee had not

performed an operability determination (i.e., a BMO) as was required by the initial

screening of ER 96-0550. Vermont Yankee (VY) administrative procedure AP 0009,

c

Revision 3, Event Report, describes the licensee's process used to assess events

resulting in adverse condition, problems or deficiencies affecting VY to initiate the

{

appropriate level of corrective action. Section C of procedure AP 0009 states,

'

" Operability concerns resulting from non-conforming plant equipment are assessed

using the BMO (Basis for Maintaining Operation) process to determine the impact of

continued operation with potentially degraded equipment."

In addition, the team noted that the licensee's root cause evaluation for ER 96-0550

attributed the problem to inadequate design review. This root cause evaluation did

not recognize that the CRV chilled water valve and dampers were missed in VY's

1989 review of NRC Generic Letter 88-14," Instrument Air Supply Problems

Affecting Safety-Related Equipment." The results of VY's 1989 review were

submitted to the NRC by letter dated February 16,1989. VY failed to identify the

1989 evaluation error and, as a result, no effort was made to evaluate other safety-

related components that may have been missed during the evaluation. Section J of

procedure requires that the ER shall have attached a report listing all root and

contributing causes.

10 CFR 50, Appendix B, Criterion XVI, " Corrective Actions," states that, " measures

shall be established to assure that conditions adverse to quality, such as failures,

malfunctions, deficiencies, deviations, defective material and equipment, and non-

conformances are promptly identified and corrected. In the case of significant

conditions adverse to quality, the measures shall assure that the cause of the

condition is determined and corrective action taken to preclude repetition." VY

failed to promptly correct the CRV deficiencies, in part, by not performing an

operability determination required by the Event Report process. VY failed to

adequately determine the cause of a condition, as evidenced by the failure to

identify and reassess the deficient 1989 engineering review for GL 88-14. The

team concluded that the two to four hour time delay required for the temperatures

in the control room to reach a significant level reduced the safety significance of

this concern and did not render the control room ventilation inoperable. The

licensee's failure to perform an operability determination as required by its

corrective action procedures, and the failure to perform an adequate cause

evaluation, are examples of inadequate corrective action and constitute a violation

of 10 CFR 50 Appendix B, Criterion XVI, Corrective Action.

(VIO 50 271/98-80-02)

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The team found that because the control room ventilation system is a system

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required to mitigate the consequences of an accident and the loss of nonsafety-

related control air would have rendered the system inoperable and this potential

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condition required the initiation of TM 96-043,the licensee should have submitted a

Licensee Event Report (LER) as required by 10 CFR 50.73(a)(2)(v)(D). The

licensee's f ailure to submit the required report was therefore a violation of 10 CFR 50.73. (VIO 50-271/98-80-03)

c.

Conclusions

The team concluded that the corrective actions for the control room temporary

modification were inadequate in that no operability determination was performed in

l

accordance with administrative procedures and the cause determination f ailed to

l

identify that the components were previously overlooked during engineering reviews

in response to NRC Generic Letter 88-14," Instrument Air Supply Problems

Affecting Safety-Related Equipment." The team concluded that the 10 CFR 50.59

safety evaluation supporting the temporary modification and procedure change

failed to address the impact of required operator actions. In addition, the +eam

concluded that the deficiency in the CR HVAC system was reportable under 10 CFR 50.73. Three violations were cited.

E3

Engineering Procedures and Documentation

E3.1

Configuration Con m1Proaram (37550)

a.

Scope of inspection

VY began a Configuration Management improvement Project (CMIP) in early 1997.

Developing design basis documents (DBDs) was one of the major projects

established in that program to retrieve, capture and maintain control of the design

basis. The team reviewed the licensee's design basis document program to assess

the licensee's control of these design documents, its control of DBD open items,

validation and changes to the DBDs.

b.

Observations and Findinas

The team observed that the intended purpose of the VY DBDs, as noted in the

licensee's Configuration Management Improvement Project Plan, dated January 22,

1988, was to be design documents for plant operations, used to respond to plant

events and to form the basis for future modifications. The team observed that

seven DBDs had been issued to date. The remaining 16 DBDs presently scheduled

were expected to be issued by the end of October 1998 in accordance with the

licensee's commitment on the docket. At present, only five of the DBDs had been

validated with the site. The remaining validations were scheduled into 2000, but

the schedule had been prioritized by system according to risk worth.

VY had failed to maintain control of pending changes to the issued DBDs. The

design control procedure AP 6007, Control, Update, and Maintenance of Vermont

Yankee Design Basis Documents, required pending or interim changes to the DBDs

(for unreviewed or unapproved and reviewed and approved changes, respectively)

to be distributed to all controlled copies of the DBDs. The team found that none of

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the controlled copies of the issued DBDs reviewed by the team had either interim or

pending change notices issued against them. The team identified examples of

interim or pending changes that should have been issued against the 4160 V ac and

the emergency diesel generator DBDs to identify the need for changes due to

revisions to the Motor Protection Guidelines, the Breaker Coordination Study, and

the Open items closeout list. The team also identified in inspection Report

50-271/98-09that the Emergency Diesel Generator DBD EDG-1 was issued without

a pending change for steady state frequency limit. 10 CFR 50, Appendix B,

Criterion ill, Design Control, requires the identification and control of design

interfaces, ir.cluding revisions of documents involving design interfaces. Failure to

control changes to the DBDs in accordance with the plant procedures is a violation

of 10 CFR 50, Appendix B, Criterion Ill, Design Control. (VIO 50-271/98-80-04)

c.

Conclusions

The team concluded that the DBD program was concentrating on the most risk

significant systems and this program was an essential part of the transition of

design engineering responsibility to VY. The team found evidence of the licensee's

failure to maintain control of changes to the issued design basis documents which

resulted in a violatior, against design control.

E4

Engineering Staff Knowledge and Performance

E4.1

Corrective Action Proaram (40500)

a.

Scope of Insoection

The licensee's process for identification of degraded or Nonconforming conditions is

described in Vermont Yankee administrative procedure AP 0009, Event Reports.

Selected portions of the Event Report (ER) process were reviewed to assess the

licensee's ability to identify and correct problems. Attributes of the process

reviewed during this inspection included the threshold for identification of problems,

the screening and prioritization of issues, the timeliness of ER evaluations, and the

trending of ER data.

A sample of approximately 35 items in the Event Report (ER) process initiated after

January 1,1998, were reviewed. The sample focused on engineering related

issues and items were selected on the basis of apparent safety / regulatory

significance from a list of approximately fourteen hundred ER descriptions. Several

of the ERs reviewed were initiated prior to January 1998 and the corrective actions

were awaiting implementation.

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b.

Observations and Findinos

The licensee's threshold for initiation of ERs appeared to be appropriate based on

the number of problems reported and the types of issues identified. The ER process

provides sufficient information to support the early identification of emerging

problerns to licensee management.

T# e team attended a sample of the VY's ER screening meetings and observed that

the meetings provide a timely and diversified assessment of new issues. The

screening committee is presented a summary of each new ER by a responsible

department head. This process allows the screening committee to evaluate the

initial response, identify the need for additional reviews, and assign a significance

level to the ER. The team observed that screening committee discussions added

value to the proposed disposition of ERs. Typically, the licensee was observed to

default to a higher significance level and request that the issue be rescreened when

more information was available. The inspectors considered this a conservative

approach.

Previous NRC inspections and SALP assessments identified ER trending as a

weakness and no significant progress has been made in this area. There are no

formal evaluations performed to assess performance trends. However, observations

by the VY staff and management have resulted in approximately 90 trend reports

for 1997. At present, the licensee is still developing the tools necessary to perform

more frequent trend evaluations and the only formal trend assessment is performed

annually. During a review of annual trend reports, the inspector noted that the

trend reports for 1993,1995,1996 and 1997 show the three most prevalent cause

codes are for written procedures, work practice, and design. It does not appear

that VY's effort to address these during past Functional Area Assessments (FAA)

[ department self assessments) have been effective. The inspector noted that as of

February 1998,23% of all ERs written in 1997 were still open and that this was an

improvement over 53% which were open during the 1996 trend report preparation.

The 1998 Trend Report indicates departmental corrective action plans are to be

developed as part of the 1998 FAA, and AP-0028 commitments had been

generated for superintendents and directors to evaluate the recurring problem areas

highlighted by the report.

The team's sample review of ERs found no examples where the operability of plant

equipment was incorrectly evaluated by the licensee. Although several examples,

such as the one discussed in Section E2.4 of this report, indicate the licensee is not

rigorous in documentation of initial operability determinations.

One of the older ERs reviewed was ER 96-0163,concerning a discrepancy between

the VY safety class manual and the approved Yankee Operational Quality Assurance

Program. Several NRC identified weaknesses associated with VY's corrective

actic,n for this ER are discussed in Section E7.1 of this report. Other examples of

the team's concerns of VY's deportability process are discussed in Section E5.1 of

this repert.

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15

c.

Conclusions

The Event Report (ER) process provides sufficient information to support the early

identification of emerging problems to licensee management. ER screening

meetings contribute the perspectives of all departments to ER disposition plans.

Trend report frequency (annual), and corrective action for recurring problems are

being evaluated by the licensee as part of AP-0028 commitments. The

documentation of initial operability determinations was not always consistent with

procedural guidance and was cited as part of a violation in Section E2.4 of this

report.

E5

Engineering Staff Training and Performance

E5.1

Deportability (37550)

a.

Scone of insoection

The team reviewed the licensee's procedural guidance on deportability to assess the

licensee's program compared to regulatory requirements contained in 10 CFR 50.72

and 50.73 and regulatory guidance contained in NUREG 1022, Rev.1, Event

Reporting Guidelines. The team reviewed selected ERs to assess the licensee's

review of problems for deportability determinations.

b.

Observations and Findinas

The team noted that the latest revision to AP 0010, Notifications and Reports Due,

Rev.1, was issued March 31,1998, and added specific reference to NUREG 1022,

Rev.1, Second Draft, but not the issued Rev.1 of NUREG 1022, which was issued

January 1998. The issued procedure contained clear, specific guidance for different

reports required by the regulations. Appendix K to the procedure contained sections

which duplicated or paraphrased the words from the regulations.

As noted in Section E8.2 of this report, prior to this inspection, the licensee had

failed to issue a timely LER for the HPCl/RCIC vacuum breaker, which is a violation

of 10 CFR 50.73. The licensee identified that it had not submitted the LER and

took prompt corrective action. The licensee's failure to meet the required 30 day

period was similar to the violation issued on April 14,1998, with Inspection Report

50-271/97-10. It was not reasonable to expect that this violation could have been

prevented by the licensee's corrective action to the previous violation. In

accordance with the Enforcement Policy Vil.B.1, this violation was not cited. (NCV

50 271/98-80-05)

As noted in Section E2.4 of this report, the team found that the licensee had failed

to evaluate ER 96-0550(on the failure of the control room HVAC on loss of

instrument air) for deportability, which was a violation of 10 CFR 50.73.

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c.

Conclusions

The team concluded the licensee issued a late LER for the HPCl/RCIC vacuum

breaker, a violation of 10 CFR 50.73. This item was similar to the violation issued

on April 14,1998 with inspection Report 50-271/97-10. No violation was issued in

accordance with the NRC's Enforcement Policy Vll.B.1.

The team concluded that the licensee's failure to evaluate the CR HVAC Event

Report for deportability as required by 10 CFR 50.73 and was a violation.

E5.2 Operability Determinations (37550, GL 91-18)

a.

Scope of Inspection

The team reviewed the licensee's guidance for operability determinations, or Basis

for Maintaining Operations (BMO), to assess the licensee's program implementation

as it related to the event reports and modifications reviewed during this inspection.

b.

Observations and Findinas

Steam Relief Valve Setooint

AP-0009, step C.1.a requires that Department Heads review ERs and contact the

appropriate individuals, as needed (e.g., Engineering or Operations's Management),

to address the operability of plant equipment. Initial operability determinations are

to be documented on Part 2.B of form VYAPF 0009.01,if degraded or non-

conforming structures, systems, or components will be considered operable. As

discussed in NRC Inspection Report 50-271/96-200,the licensee had not always

been rigorous about documenting operability determinations and VY was not able to

promptly determine whether operability was affected or even considered. For

example, ER 98-0421 documented that the FSAR described relief valve setpoint

range for the nuclear steam supply system was greater than allowed by Technical

Specifications. The team's review of the vendor's documentation, the licensee's

purchase order and calibration criteria found that the acceptance criteria used by the

vendor to accept the relief valve setpoints were verbally changed by the licensee to

conform to the Technical Specification 2.2 allowed limits without any formal

procurement controls. The ER was assigned a significance level of three, and no

l

assessment was documented as to the operability of the installed relief valves.

'

Based on the team's questions, the licensee was able to provide documentation

showing the relief valve setpoints were set in accordance with the Technical

Specifications. The failure to document the initial operability determination as

required by AP-OOO9 constitutes a violation of minor significance and is not subject

to formal enforcement action. However, this item was another example of weak

licensee control of vendor supplied services.

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Primary Containment Peak Pressure

The team observed that the licensee had identified a potential concern with post-

LOCA primary containment pressure and associsted 10 CFR 50, Appendix J testing

requirements. Two issues had been identified by the licensee or its nuclear steam

system supplier (NSSS), General Electric (GE): (1) based on a review of the analysis

associated with operating the reactor under Extended Load Line Limit Analysis

(ELLLA) it was determined that the primary containment peak pressure would be

increased by 2.6 psig; and, (2) recalculation of the torus free air volume resulted in

an increase of 1 psig to th( primary containment peak pressure.

Regarding item (1), based on GE's review of the analysis associated with operating

the reactor under ELLLA, it determined that the primary containment peak pressure

would be increased by 2.S psig. Also, recalculation of the torus free air volume

resulted in an increase ci 1 psig to the primary containment peak pressure. When

these values are added to the FSAR 14.6.3.3.2 calculated value of 42.2 psig, the

new peak accident pressure becomes 45.8 psig. This exceeds the current leak rate

testing test pressure (Pa = 44 psig) by 1.8 psig and potentially invalidated the

Appendix J leak rate testing results. A higher post accident primary containment

pressure could result in releases of airborne radioactivity outside the design limits.

Regarding item (2), new torus free air volume calculations were recently done by

the licensee and showed that the free air volume was less than that used before

which translates into a higher (by 1 psig) post accident containment pressure.

A Basis for Maintaining Operation (BMO) has been issued to allow the plant to

startup. Per the BMO a conservative reanalysis has been done by General Electric

which provided a new calculated peak accident pressure, including the ELLLA and

reduced torus volume concerns, that is less than the current primary containment

test pressure (Pa) of 44 psig.

This item will remain open pending completion by General Electric of the final

analysis for VY showing that with VY specific data the resulting peak accident

pressure, considering ELLLA and the reduced torus air volume, is less than or equal

to 44 psig. (IFl 60 271/98-80-06)

Control Room HVAC

As noted in Section 2.4 of this report, the team found that the licensee had failed to

perform an opervuii;ty evaluation for ER 96-0550, failure of the CR HVAC on loss of

instrument air, and contributed to the violation of 10 CFR 50, Appendix B, Criterion

XVI, Corrective Action,

c

Conclusions

The team concluded that the licensee's control of vendor supplied services for the

steam relief valve setpoints was weak.

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The team concluded that, even though the analysis had not been finalized

specifically for Vermont Yankee, the licensee's conservative approach, using an

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analysis from a.similar plant with key VY values incorporated, provided reasonable

assurance that the plant could startup and operate safely. An inspector follow-up

item was opened.

The team concluded that the licensee's failure to produce a BMO to support the ER

on the CR HVAC issue was a violation of Criterion XVI, Corrective Action.

E6

Engineering Organization and Administration

E6.1

Desian Enaineerina (37550)

a.

Scope of Insoection

The team interviewed engineering management, design engineering supervision and

design engineers to assess the progress to date of the transition from a Yankee

Atomic Electric Cornpany (YAEC) to a Vermont Yankee (VY) design engineering

staff located at the Vermont site.

b.

Observations and Findinas

The team found that the reorganization of engineering under the VY staff has

resulted in the establishment of the new position of Vice President (VP) of

Engineering and a realignment of the engineering groups directly under the new VP.

Prior to this reorganization, engineering reported to the VP of Operations, through

the plant manager. Retention of the former YAEC engineering personnel that had

been assigned to the VY project remained high. The transition to a site-based

design engineering organization was expected to be completed by the end of 1999.

The Configuration Management improvement Project (CMIP) was being managed

from the former YAEC-now Duke Engineering and Services-offices in Bolton, MA.

This major engineering effort to support the engineering transition to the site was

progressing, but behind the original schedule submitted to the NRC as part of the

industry 50.54(f) request on design information. VY had informed the NRC of the

change to the DBD preparation slippage, but had not formally told the NRC about

the DBD Validation schedule change. The licensee indicated it was reviewing its

manpower loading forecasts before it submitted the revised validation schedule to

the NRC. Six DBDs had been issued by the end of the inspection. Five of those

had been validated. Following the close of the inspection, the team was informed

that this effort would be managed from the VY site and a VY site manager had been

named to lead this effort.

c.

Conclusions -

The team concluded that the design engineering organization and the transfer of

design responsibility to the site continues to be progressing without any observed

problems that would affect plant safety.

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E6.2 Systems Enaineerina (37550)

a.

Scooe of Insoection

The team interviewed engineering management, design engineering supervision and

system engineers to assess the progress in the development of the system

engineering program at Vermont Yankee. The team also reviewed selected systems

engineering

. ;k procedures and work products, such as system notebooks and

system health reports, to assess the sensitivity of the system engineers to potential

system problems.

b.

Observations and Findinas

The team found that the system engineering organization at VY consisted of sixteen

engineers who monitor the status of 81 maintenance rule systems. At present, the

system engineers are not the first level responders to daily problems; that task

falling to the maintenance engineers. The primary task for the VY system engineers

is to step back and take a broad assessment of the system to identify potential

problem components and recommend system improvements. The notebooks and

system health reports reviewed by the team demonstrated good knowledge of the

system and an understanding of system problems. The system engineers training

followed the Institute of Nuclear Power Operations (INPO) guidelines for engineering

support personnel (ESP).

c.

C inclusions

The team concluded that the VY Systems Engineering organization continued to

show progress in implementing its mission consistent with the industry expectations

for system engineers. The team concluded that the system engineers' notebooks

and system health reports reviewed by the team were consistent with those goals.

E7

Quality Assurance in Engineering Activities

E7.1

Quality Assurance Proaram Chanae

a.

jnpoection Scope (40500)

On March 11,1996, Event Report 96-0163 was initiated to document that the

Vermont Yankee Safety Classification Manual (VYSCM) was not in compliance with

the approved Yankee Operational Quality Assurance Program (YOOAP),

Revision 27. The team reviewed the licensee's corrective actions and compliance

with the requirements of 10 CFR 50.54(a) for changes to the approved quality

assurance plan.

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

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_ _ _ _ _ _ _ _ _ - _

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f:

20

b.

Observations and Findinas

..The VY Final Safety Analysis Report (FSAR), Appendix.D, " Quality Assurance

Program During the Operational Phase," references the Quality Assurance Prograrr.

as described in FSAR Section 1.9. Section 1.9 describes the Yankee Operational

Quality Assurance Program (YOQAP) as the means for compliance with 10 CFR 50

Appendix B requirements. Section Vil, of YOQAP, Appendix B, identifies that VY'

has taken exception to Regulatory Guide 1.26, Revision 3, " Quality Group

Classifications and Standards for Water , Steam- and Radioactive-Waste-Containing

Components of Nuclear Power Plants." As an alternative, the exception states that

,

_ VY_ will continue to classify structures, systems, and components (SSC) in

!=

accordance with ANS-22, Draft No. 4, Rev.1, May 1973, " Nuclear Safety Criteria

for the Design of Stationary Boiling Water Reactor Plants." This exception was

accepted by the NRC as far back as 1982 as part of Revision 11 to YOQAP.

The licensee's evaluation of ER 96-0163in 1996 found that classification of SSCs

was being made using ANS-52.1,1983, Nuclear Safety Criteria for the Design of

Stationary Boiling Water Reactors,"instead of the Draft 4 version of ANS-22 that

was approved by exception by the NRC.

As corrective action for the ER, Yankee Atomic Electric Company (YAEC) submitted

Revision 28 of the YOQAP, on behalf of VY, to the NRC for approval on October 1,

1997. This revision identified VY's new alternative to Regulatory Guide 1.26 as a

change to a regulatory commitment (i.e., a reduction in commitment) that needed

NRC approval.

10 CFR 50.54(a) states that " Changes to the quality assurance program description

that do reduce the commitments must be submitted to the NRC and receive NRC

approval prior to implementation..." When Revision 28 of YOQAP was submitted to

the NRC for approval, the licensee had already determined that the change was a

reduction in commitment but allowed its continued implementation under the

existing version of the VYSCM. The failure to receive NRC approval prior to

implementing a change reducing previous quality assurance (QA) program

commitments is a violation of 10 CFR 50.54(a). (VIO 50-271/98-80-07)

The inspector also noted that on February 6,1998, a contractor study performed

for VY clearly identified a discrepancy between the criteria for classification of

Radioactive Waste Processing Systems in ANS 22 and the VYSCM. The

discrepancy concerns the whole body dose limit used to assess system failures.

ANS 22 requires failures which result in a dose of 170 mrem or greater (at the site

boundary) be designated as safety class and the VYSCM specifies a limit of

500 mrom. As a result, systems which should be designated as safety class, under

the YOQAP may be designated as non nuclear safety. The inspector found that the

licensee had not evaluated the impact on plant equipment that could result from this

discrepancy. The licensee's initial review found that the classification of the

refueling equipment was potentially affected by implementation of the less

restrictive standard. The licensee initiated ER 98-1235, on May 21,1998, to

~ investigate, this issue and adequate compensatory measures were established.

I

.

.

21

A letter from VY to the NRC, dated February 25,1998, described the VY licensing

basis, relative to dose criteria for classification of safety class equipment, as

1

500 mrem. Based on the FSAR reference used by VY, this appears to be incorrect

and may have been confused with 10 CFR 20 limits. This issue needs further NRC

review to determine if quality assurance requirements were met since the inspectors

l

did not complete its review of the February 25,1998, submittal. (URI 50-271/98-

,

'

80-08)

c.

Conclusions

l

A change to the Quality Assurance Program that reduced previous commitments

was implemented prior to NRC approval and is cited as a violation of 10 CFR 50.54.

!

'

The licensee did not address the potential impact on plant equipment and continued

implementation of the unapproved standard. This indicated a weakness in

implementation of the corrective action process. An unresolved item was opened

pending completion of NRC's review of a related licensee submittal.

E7.2 Self Assessments

a.

Inspection Scopa (40500)

The team reviewed the effectiveness of the quality assurance organization in

identifying problems in functional areas. This was accomplished by reviewing

audits and assessments. The team selected Functional Area Assessments (FAAs)

from the 1996-1997 for review. These included the following FAAs:

Technical Support, including Audit No. VY 98-17, " Corrective

Action / Operating Experience"

Systems En;;.neering

Mechanical Engineering

Electrical and Controls Maintenance

General Plant Performance

b.

Observations and Findings

The team's review of the FAA program and results of the QA audits found the

assessment program plan was appropriate. The team found that the assessments

were broad in scope and presented substantial findings and observations including

recommendations for those functional areas requiring additional management

attention. The team noted that the findings were clearly stated, directed to the

appropriate personnel, and appropriately entered into the corrective actions

program. The team verified appropriate resolutun of selected findings.

Additionally, the team found that required periodic audits were appropriately

performed by the QA program.

.

.

22

c.

Conclusions

The team concluded that the QA program instituted at VY to provide oversight of

the FAA were acceptable and use of the self assessment program was effective.

E8

Miscellaneous Engineering tssues

E8.1

Loadina on Safety Bus Number 9

a.

Insoection Scope

The team reviewed loading on safety bus number 9 to assess the capability of the

bus to support fire pump testing independent of the connected load. This consisted

of reviewing procedures and calculations to determine what, if any, initial conditions

are required or implemented on 480 Volt bus 9 prior to testing the electric driven

fire pump. The team also reviewed Maintenance Planning and Control (MPAC) data

for bus number 9 equipment and computer records during the last test of the

electric driven fire pump to assess the margin on bus 9.

b.

Observations and Findinas

The team reviewed procedure number OP 4105, " Fire Protection System

Surveillance," Revision 8, to determine if initial conditions should be specified or

precautions stated prior to performing fire pump testing on bus number 9. The

team found that there were no initial conditions or precautions identified nor

required in the procedure for bus loading concerns. In addition, the team confirmed,

from a review of the computer records, that the last test of the 250 hp electric

driven fire pump performed prior to the refueling outage (RFO 20) was performed

with the 250 hp control rod drive pump also being powered from the same bus

without incident.

The team reviewed calculation VYC-1688, Transient Voltage on 480 Volt Power

System, and confirmed that the assumptions used in the analysis were conservative

and the results demonstrated sufficient margin exists to start and accelerate the fire

pump without overloading the station service transformer T-9-1 A or bus 9 or having

a negative effect on the running equipment.

The team also reviewed MPAC data for equipment located on bus number 9 and

found that there had been no equipment trips since June 22,1992. On that date,

the team found that motor generator rotating uninterruptible power supply 1 A

tripped as reported in LER 92-018.

c.

Conclusions

The team concluded that there was sufficient margin available with the station

service transformer, bus 9 rating and bus 9 feeder breaker overcurrent relay setting

to permit the testing of the fire pump under all operating conditions.

l

l

t

.

.

23

E8.2 Licensee Event Reports (92903)

(Ocen) LER 98-005: HPC1/RCIC Exhaust Lines Susceptible to Water Hammer. This

LER, issued on April 9,1998, documented a discrepancy, identified by the licensee

on January 15,1998 as a result of its DBD effort, that the current installation of the

HPCl/RCIC vacuum breakers could result in water hammer in those lines.10 CFR 50.73 requires an LER be submitted to the NRC within 30 days after the discovery

of the event. Deportability was discussed in Section E5.1 of this report.

Modification EDCR 98-402, HPCl/RCIC Vacuum Breakers, moved the location of the

vacuum breakers in the syste;m and provided updates to the FSAR and the Design

Basis Documents (DBD) for HPCI and RCIC to include a description of the installed

vacuum breaker configuration. Previously there was no discussion of the vacuum

breakers in the FSAR. The DBDs are in the initial draft stage.

This issue will close with: (1) the installation of EDCR 98-402, HPCl/RCIC Vacuum

Breakers; (2) issuance of associated documentation updates to maintain

configuration control; and, (3) corrections to the Safety Evaluation associated with

EDCR 98-402.

Regarding item (1), the recently installed design change modified the existing

vacuum breaker arrangement on the HPCI and RCIC turbine exhaust lines to take

suction from the torus atmosphere rather than from the reactor building Standby

Gas Treatment System. The modification resolved the water hammer problems and

installed a design that was consistent with other utilities and with General Electric

service information letter (SIL) No. 30, which addressed this problem in 1973. This

portion of the LER is closed.

Regarding item (2), a review of the proposed changes to the FSAR and the DBDs

indicated that the proposed changes did not adequately describe the design basis

for the HPCI or RCIC vacuum breakers / pressure equalizing lines. Also, the Training

Module for the design change inadequately describes the basis for the change.

This issue will remain open until the configuration control input documentation for

the FSAR and the DBD's have been adequately revised.

Regarding item (3), the Safety Evaluation associated with EDCR 98-402 was

inadequate in that it failed to address the new containment leakage path created

and the associated impact on 10 CFR 100. Also, the safety evaluation did not

adequately address all applicable water hammer scenarios for which the design

I

change was needed to eliminate. This issue, discussed in Section E2.1 of this

report, was cited as a violation of 10 CFR 50.59 and will remain open pending NRC

l

review of the licensee's response to that violation.

l

This LER will remain open pending resolution of items (2) and (3).

l

l

(Open) LER 98-010: Potential challenge to containment systems in the event of a

LOCA. The emergency operating procedures (EOPs) regarding Torus Rupture Disc

Burst Pressure were inadequate in that they did not prevent or caution the operators

about the possibility of prematurely bursting the rupture disc which causes a loss of

L

_ _ - _ _ - _ - _

_ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ - _ _ _ _ _ _

_

.

.

24

l

primary containment integrity. The Licensee failed to issue a timely LER when the

problem was discovered and, consequently, a violation was issued in inspection

report 50-271/98-06.

The licensee has closed a motor operated valve in the hardened vent discharge line

to provide short term corrective action to ensure that primary containment integrity

was maintained during a containment flooding evolution. A Basis for Maintaining

Operations (BMO) had been prepared to support continued operation with the torus

vent system isolation valve closed pending final resolution of this issue. This LER

remains open pending resolution of the issue, closure of the BMO and final review

by the NRC.

E8.3 Previousiv Reviewed items

LQlosed) VIO 50-271/97-10-07: Failure to Perform a Safety Evaluation

The licensee failed to perform a safety evaluation prior to reclassi'ying the safety-

related unit coolers RRU 5 and RRU 6 to nonsafety-related on December 30,1994.

The licensee's March 6,1998, response to the NRC's February 5,1998, notice of

violation identified corrective actions including a safety evaluation for the

reclassification of the coolers, update of design basis documentation and the FSAR,

and programmatic enhancements in the areas of design control and configuration

management. The inspector reviewed the safety evaluation, the pending FSAR

change, and the Configuration Management Improvement Project Plan dated

January 22,1998. No problems were identified with the licensee's safety

evaluation or proposed programmatic improvements. The inspector had no further

questions.

(Closed) VIO 97-06-03: Failure to Take Effective Corrective Action for SBGT

System Potential Over-pressurization

On April 24,1997, the licensee prematurely concluded that inerting and de-inerting

operations with the reactor at power were in accordance with the VY licensing

bases. Subsequent to inerting activities on May 8,1997, with the reactor at

power, the licensee determined that this conclusion was incorrect and that VY had

been operated outside its licensing basis. The inspector verified a sample of the

licensee's commitments in the October 31,1997, response to the violation.

Corrective actions included interim administrative controls and a final resolution

through a TS amendment issued on May 14,1998. Through a review of records,

the inspector found that the licenseo provided training to management and

en0 neering staff on design and licencing basis issues and that the Licensing

i

Department had delineated the roles and expectations for licensing engineers.

1 Closed) IFl 50-271/96-200-01: Event Report Program Weaknesses

The 1996 Corrective Action Program inspection identified weaknesses in the

implementation of the ER program and its procedural guidance. Specifically,

timeliness goak of the ER process were not routinely met and procedural guidance

_ _ _ _ _ _ ___-___ __ __________

_ _ - _ _ _ _

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.

25

was weak regarding the threshold for identification of issues and the process for ER

closure. In response to these issues, the licensee eliminated ER due date extensions

and established corporate timeliness goals to monitor overdue ERs and the backlog

of ER commitments. By the end of 1997, the licensee essentially eliminated its

backlog of approximately 150 overdue ERs. Although the licensee's process allows

extension of commitment due dates, the corporate goal is based on the commitment

age and therefore is independent of the extension process. In 1997 the corporate

performance goal was met. A review of AP 0009, Event Reports, Revision 8, found

,

l

that the licensee had made revisions to clarify expectations for ER initiation

thresholds and the process for ER closure. Based on the number of ERs generated

since this IFl was opened, it was apparent the licensee had lowered the threshold

for initiating ERs. This inspector follow-up item is closed.

E8.4 FSAR Review

A recent discovery of a licensee operating its facility in a manner contrary to the

Updated Final Safety Analysis Report (UFSAR) description highlighted the need for a

special focused review that compares plant practices, procedures and/or parameters

to the FSAR description. While performing the inspections discussed in this report,

the inspectors reviewed the applicable portions of the FSAR that related to the

areas inspected. The following inconsistencies were noted between the wording of

the UFSAR and the plant practices, procedures and/or parameters observed by the

inspectors.

The team reviewed portions of FSAR Chapters 1,6,10,14 and Appendix D during

this inspection. The team noted that the VY quality assurance program was

described in Chapter 1 and Appendix D and referred to the YOOAP. As noted in

Section E7.1 of this report, a violation was issued for failing to obtain NRC approval

prior to making changes to QA commitments. The team noted that the HPCl/RCIC

system operation was described in Chapters 6 and 14 and the control room

ventilation system was described in Chapter 10. As noted in Sections E2.1 and

E2.4 of this report, a violation was issued for incomplete safety evaluations of

changes to these systems.

V. Manaoement Meetinos

X1

Exit Meeting Summary

A exit meeting was held on June 5,1998 with Mr. Leach and others on the VY

staff to discuss the purpose and to review the results of the inspection, including

the violations cited in this report. Mr. Maret attended the meeting by phone. The

meeting was attended by Mr. J. Wiggins, Director, Division of Reactor Safety, for

the NRC in Region 1. The licensee did not question the observations and findings

presented by the team during the meeting. The licensee confirmed that no

. proprietary information was used during this inspection.

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_

.

.

PARTIAL LIST OF PERSONS CONTACTED

Vermont Yankee

M. Balduzzi

Plant Manager, formally Operations Superintendent

R. Barkhurst

President and CEO

K. Bronson

Operations Manager

D. Catsyn

Technical Support Manager

P. Corbett

Project Engineering Manager

J. DeVincentis

Assistant to Director of Engineering

A. Doyle

DBD Program Manager

F. Helin

Operations Superintendent / Technical Services Supt.

R. January

Electrical and l&C Design Engineering Manager

D. Leach

VP, Engineering

D. Legere

Systems Engineering Manager

E. Lindamood

Director of Engineering

D. McElwee

Liaison Engineer

P. McKinney

Lead Systems Engineer - Electrical

G. Maret

Director of Operations, formally Plant Manager

M. Metell

Mechanical Design Engineer

R. Ramsdel

Tech Support Corrective Actions Engineer

M. Watson

Maintenance Superintendent

G. Werzbowski

Lead Systems Engineer - Mechanical

NRC

W. Rutand

Chief, Electrical Engineering Branch, DRS, Region 1

J. Wiggins

Director, Division of Reactor Safety, Region 1

I

1

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.

.

INSPECTION PROCEDURES USED

37001

10 CFR 50.59 Safety Evaluation Program

37550

Engineering

40500

Effectiveness of Licensee Controls in Identifying, Resolving,

and Preventing Problems

92903

Follow-up - Engineering

ITEMS OPENED, CLOSED and DISCUSSED

Qoened

50-271/98-80-01

VIO

Failure to Perform Adequate Safety Evaluation

50-271/98-80-02

VIO

Inadequate implementation of Corrective Action Program

50-271/98-80-03

VIO

Failure to issue Required Reports to NRC

50-271/98-80-04

VIO

Failure to Control Changes to Design Basis Documents

50-271/98 80-06

IFl

Containment Pressure Response

50-271/98-80-07

VIO

Failure to Obtain NRC Approval Prior to Revising QA

Commitments

50-271/98-80-08

URI

Complete Review of February 25,1998 Submittal

Opened / Closed

50-271/98-80-05

NCV Failure to submit a Timely LER

50 271/98-80-09

NCV inadequate Safety Evaluation

Closed

50-271/97-06-03

VIO

Criterion XVI

50-271/97 10-07

VIO

Safety Evaluation

50-271/97-200-01 IFl

Event Report Program Weaknesses

Discussed

50-271/98 276

LER

LER 98-005-00

HPCl/RCIC Exhaust Lines Susceptible to

Water Hammer

50-271/98-306

LER

LER 98-010-00

Challenge Containrnent Systems in Event

of LOCA

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.

LIST OF ACRONYMS USED

AEC

Atomic Energy Commission

ACS

Alternate Cooling Source

ANS

American Nuclear Society

AOG

Advanced Off-Gas System

AUX

Auxiliary Transformer

BMO

Basis for Maintaining Operation

CFR

Code of Federal Regulations

CGD

Commercial Grade Dedication

CMIP

Configuration Management improvement Project

CRP

Control Room Panel

CRV

Control Room Ventilation

DBD

Design Basis Document

DC

Direct Current

DE&S

Duke Engineering and Services

DG

Diesel Generator

EDCR

Engineering / Design Change Request

eel

Escalated Enforcement item

ELLLA

Extended Load Line Limit Analysis

ER

Event Report

FAA

Functional Area Assessment

FSAR

Final Safety Analysis Report

GDC

General Design Criteria

GE

General Electric

HELB

High Energy Line Break

HP

Horsepower

HPCI

High Pressure Coolant injection

HVAC

Heating, Ventilating and Air Conditioning

IFl

Inspector Follow-up Item

INPO

Institute of Nuclear Power Operations

KV

kilovolt

LCO

Limited Condition for Operation

LER

Licensee Event Report

LOCA

Loss of Coolant Accident

MM

Minor Modification

MPAC

Maintenance Planning and Control

NCV

Non-Cited Violation

NRC

Nuclear Regulatory Commission

NRR

Nuclear Reactor Regulation

NSSS

Nuclear Steam Supply System

P&lD -

Piping and Instrument Diagram

PORC

Plant Operations Review Committee

PSIG

Pounds per Square Inch Gauge

!

QA

Quality Assurance

RBCCW

Reactor Building Closed Cooling Water

RCIC

Reactor Core isolation Cooling

i

RFO

Refueling Outage

RG

Regulatory Guide

RHRSW

Residual Heat Removal Service Water

1

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.

.

2

SALP

Systematic Assessment of Licensee Performance

SIL

Service information Letter

SSC

Structures, Systems, and Components

SUT

Startup Transformer

SW

Service Water

TIP

Trans Incore Probe

TM

Temporary Modification

TS

Technical Specification

URI

Unresolved item

USO

Unreviewed Safety Question

VIO

Violation

VY

Vermont Yankee

VYSCM

Vermont Yankee Safety Classification Manual

YAEC

Yankee Atomic Electric Company

YOQAP

Yankee Operational Quality Assurance Program

..

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