ML20137M965

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Insp Repts 50-327/85-46 & 50-328/85-46 on 851209-13. Violations Noted:Failure to Establish & Maintain Adequate Surveillance & Sys Operating Instructions & Conduct Adequate Plant Operations Review Committee Reviews
ML20137M965
Person / Time
Site: Sequoyah  Tennessee Valley Authority icon.png
Issue date: 01/22/1986
From: Bearden W, Ignatonis A, Jenison K, Shymlock M, James Smith, Tgnatonis A
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20137M932 List:
References
50-327-85-46, 50-328-85-46, NUDOCS 8601290111
Download: ML20137M965 (24)


See also: IR 05000327/1985046

Text

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UNITED STATES

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NUCLEAR REGULATORY COf,IMISSION

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REGION 11

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101 MARIETTA STREET.N.W.

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ATLANTA, GEORGI A 30323

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Report Nos.:

50-327/85-46 and 50-328/85-46

Licensee: Tennessee Valley Authority

6N38 A Lookout Place

1101 Market Street

Chattanooga, TN 37402-2801

Docket Nos.: 50-327 and 50-328

License Nos.:

DPR-77 and DPR-79

Facility Name:

Sequoyah Units 1 and 2

Inspection Conducted: December 9, through December 13, 1985

Inspectors:

(I b. ,}lnn,Gh+th

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A. J. IgnatJnis', Gnypection Team Leader

Date Signed

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pK.M.JeniYon,SenthResidentInspector

Date Sfgned

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da1/n

g W. C. Beardert, Resi~deht Inspectnr

Date Signed

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th a/r4

J. D. Smith,(Inspect}bn Specialist, 0IE

Date Signed

EPb&YrDt/td

^20-66

M. B. Shymlock / Senior Resident Inspector

Date Signed

Approved by:D . Weise, Section Chief

Date Signed

Division of Reactor Projects

SUMMARY

Scope:

This special, announced inspection involved 210 inspector-hours onsite in

the areas of 50.54(f) letter followup and operational readiness verification

including, NRC Bulletins and Notices, Corporate and Sequoyah Nuclear Plant

Commitment Tracking Systems, Operating Experience Review, Reactor Trip Reduction

Program, Modifications, Surveillance Instruction review, and licensee's evalua-

tion of the Davis-Besse Event described in NUREG-1154

Results:

In the areas inspected, three violations with multiple examples were

identified:

1.

Failure to establish and maintain adequate surveillance and system operating

instructions (paragraphs 6.a. and 6.b.).

0601290111 060122

PDR

ADOCK 05000327

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2.

Failure to feplement procedures (paragraph 6.a).

3.

Failure to conduct adequate PORC reviews (paragraphs 10.a. and 10.b.).

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REPORT DETAILS

1.

Licensee Employees Contacted

    • H. L. Abercrombie, Site Director
  • P. R. Wallace, Plant Manager
  • L. M. Nobles, Operations and Engineering Superintendent
  • B. M. Patterson, Maintenance Superintendent
  • J. M. Anthony, Operations Group Supervisor
  • L. C. Bush, Operations Group Assistant Supervisor
  • R. W. Olson, Modifications Branch Manager
  • M. R. Sedlacik, Electrical Section Manager, Modifications Branch
  • L. D. Alexander, Mechanical Section Supervisor
  • M. A. Skarzinski, Electrical Maintenance Supervisor
  • H. D. Elkins, Instrument Maintenance Group Manager

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G. B. Tiner, Instrument Maintenance Engineer

  • M. R. Harding, Engineering Group Manager

D. C. Craven, Quality Assurance Superviser

  • G. B. Kirk, Compliance Supervisor
  • R. C. Birchell, Compliance Engineer
  • R. W. Fortenberry, Engineering Section Supervisor
  • R. M. Mooney, Systems Engineering Supervisor
  • R. J. Griffin, NSRS Site Representative
  • J. A. Dunlap, DPS0 Supervisor
  • C. R. Brimer, Site Services Manager
  • W. S. Wilburn, Technical Services Supervisor
  • J. H. Sullivan, Regulatory Engineering Supervisor
  • D. L. Cowart, Quality Surveillance Supervisor
  • C

E. Bosley, Quality Assurance Auditor

  • J. L. Hamilton, Quality Engineering / Quality Control Supervisor
  • T. E. Burdette, Quality Assurance
  • R. W. Moore, Quality Assurance Manager
  • C. E. Chmielewski, Nuclear Engineer
  • C. L. Wilson, Nuclear Engineer

Other licensee employees contacted included technicians, operators, shift

engineers, security force members, engineers and maintenance personnel.

NRC Resident Inspector

    • S. P. Weise
  • L. J. Watson
  • Attended exit interview December 13, 1985
    • Attended exit interview telecon January 14, 1986

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2.

Exit Interview

The inspection scope and findings were summarized with the Plant Manager and

members of his staff on December 13, 1985.

After Regional management

review, a telephone exit interview was conducted on January 14, 1986, to

further present the inspection findings.

Three violations with examples

described in paragraphs 6.a. ,

6.b.,

10.a. and 10.b. were discussed in

detail.

Four unresolved items were identified during this inspection and

are discussed in paragraphs 6.a

8, and 10.c.*.

The licensee acknowledged

the inspection findings.

Information on reactor protection setpoint

methodology was identified as proprietary, but is not incorporated in this

report.

During the reporting period, frequent discussions were held with

the Site Director, Plant Manager and his assistants concerning inspection

findings. At no time during the inspection was written material provided to

the licensee by the inspector.

3.

Licensee Action on Previous Inspection Findings (92702)

(Closed) Unresolved Item 327, 328/85-43-01, Failure to Update Procedure

S0I 30.6, Auxiliary Building Gas Treatment System (ABGTS).

Inspector review

of SOI 30.6 and ABGTS walkdown identified a discrepancy in the amperage

rating of fuses specified in 501 30.6 versus the ones installed in the local

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control panel for the ABGTS humidity control heaters.

The inspector

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reviewed ABGTS modification made in 1984 and upgraded this Unresolved Item

to a violation. Details are provided in paragraph 6.b.

4.

Licensee Commitment Tracking System

The licensee's commitment tracking system was reviewed to determine its

viability, extent and implementation.

The following documents were

reviewed:

a.

TVA's Nuclear Performance Plan submittal dated November 1,

1985,

containing Volume 1, the Corporate Plan and Volume 2, the Sequoyah

Plan.

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b.

TVA memorandum L44 850919 805, Policy Regarding Control Over Making

Commitments To The Nuclear Regulatory Commission, Tracking Commitments

Through Implementation, and Maintaining Commitments Throughout Plant

Life - H. G. Parris, September 26, 1985.

c.

TVA memorandum L44 850927 801, Policy Regarding Control Over Making

Commitments To The Nuclear Regulatory Commission, Tracking Commitments

Through Implementation, and Maintaining Commitments Throughout Plant

Life - W. T. Cottle, October 2, 1985.

  • Unresolved items are matters about which more information is required to

determine whether they are acceptable or may involve violations or deviations.

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Volume 1, Section 3.2 of the Corporate Nuclear Performance Plan (NPP) states

that Sequoyah Nuclear Plant (SQN) is working on full implementation of the

corporate policy for maintaining all NRC commitments on the Corporate

Commitment Tracking System (CCTS).

Full implementation of the CCTS at SQN,

was to be completed by Dctember 31, 1985.

The corporate Nuclear Licensing

Staff (NLS) was assigned the responsibility of making initial entries into

the CCTS and ensuring that they have appropriate management review and

approval.

TVA memorandum L44 850927 801 provides program guidance for implementing the

corporate policy on commitment tracking.

Included in this letter is the

purpose of the CCTS and delineation of the TVA nuclear facility and Cor-

porate Nuclear Licensing Branch responsibilities.

The purpose of the CCTS

is to ensure that commitments to NRC are evaluated, approved, documented,

tracked, implemented, and maintained to ensure regulatory compliance.

The

SQN staff responsibilities are as follows:

a.

Make and/or modify commitments to NRC relating to SQN.

b.

Evaluate proposed commitments to ensure that they are necessary,

accurately defined, achievable, and sufficient to satisfy regulatory

requirements.

c.

Track, implement, and maintain continued compliance of NRC commitments.

d.

Maintain appropriate coordination of commitment actions with other TVA

organizations.

Although the CCTS was not fuTly implemented, the inspectors reviewed the

current SQN tracking system and compared it to the available CCTS.

Site

input to the formative stages of CCTS appeared minimal.

The SQN staff

appeared to have had little participation in the formative process. The SQN

staff was maintaining a separate computerized tracking system (Commitment

Action Tracking System - CATS) which they planned to use to support the

CCTS. The inspectors found that the format of the CCTS is incompatible with

CATS and that the information presented in CCTS is not detailed enough to

identify multiple facets within the same commitment.

The tracking identi-

fication numbers of the two systems used different numbering schemes to

itemize commitments.

Further, the inspectors found a lack of program

coordination between the corporate Nuclear Licensing Staff and the SQN

staff.

For example, SQN did not use the prescribed format for data entry

into the CCTS.

Instead, the locally generated CATS form was used. The SQN

use of the CCTS appeared to be in the input mode only.

The inspector discussed the above concerns with the SQN Site Director. The

SQN Site Director acknowledged that the SQN staff does not use the pres-

cribed format input for CCTS and that there is format incompatibility

between CATS and CCTS.

The Site Director indicated that the CCTS Corporate

policy would be properly implemented at SQN by December 31, 1985.

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As reviewed, neither the CCTS or the CATS addresses written commitments that

are completed based on exit interview information and prior to the issuance

of an NRC violation response. This means a record of the commitment and its

completion is not preserved.

If a commitment required future repetitive

actions (i.e., training, operator experience review, Health Physics audits,

etc.), these future actions would not appear in either system because the

item would be closed when the commitment was met initially.

The definition of commitment per TVA memorandum L44 850927 801, is a written

and docketed statement of TVA actions taken or to be taken by some future

date.

By this definition, written TVA commitments can encompass a variety

of subject items which should include FSAR commitments, written licensee

commitments on which SER assumptions were based, responses to deviations,

and written commitments made in response to NRC/TVA meetings and NRC

letters.

Hence, according to the commitment definition, the scope of the

commitments can be very broad.

To address the potential of missed commit-

ments at SQN the licensee comitted in SQN NPP, volume 2, to review past

NRC commitments back to January 1,1981, in the areas of past violation

responses

IE Bulletin responses, licensee event reports, and NUREG-0737

items. TVA will review the above items prior to unit startup.

The SQN staff was developing an implementing policy Standard Practice

(SQA-135) to support the CCTS.

This procedure was in the review process at

the time of this inspection.

The NRC will review this implementing policy

and verify implementation of CCTS per SQA-135 after the program is imple-

mented.

The licensee also had not established a system for independent

verification of commitment completion at the time of the inspection.

This

is an Inspector Followup Item (327,328/85-46-01).

5.

IE Bulletin No. 85-02, Undervoltage Trip Attachments on Westinghouse DB-50

Type Reactor Trip Breakers

The inspectors reviewed the IE Bulletin and the licensee's response letter

dated December 3,1985.

The licensee committed in their response to IEB 85-02 to install the automatic shunt trip modification on the reactor trip

breakers prior to the restart of each respective unit. The inspectors also

verified that the Main Feedwater System Isolation Valve, Feedwater Regula-

tion Valve, and Feedwater Regulation Bypass Valve electrical configuration

were as described in IEB 85-02 (reference: drawing 47W611-3-2).

In conjunction with the bulletin review, the failure of the undervoltage

output circuit boards in the Westinghouse designed Solid State Protection

System (SSPS), which was addressed in IE Information Notice 85-18 was also

reviewed. The following procedures were reviewed:

IMI 99 - SSPS, Reactor Protection System

TI 52, Special Instruction for Removing the SSPS from Service and

Returning it to Service.

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IMI 99 FT 18, Reactor Protection System Functional Test

SI-227, Response Time Testing Reactor Protection System Trip Function

SI-227.1, Post-Maintenance Response Time Test of Reactor Trip Breakers

RTA and RTB

Surveillance Instruction (SI) 227.1 requires that, after performance

of

maintenance on the reactor trip breaker or when the technician has reason

to believe that damage has been done to the protection circuit, Instrument

Maintenance Instruction (IMI) 99 FT 18 be performed.

SI 227.1 does not

require that this functional test be performed following trouble shooting in

the Solid State Protection System circuits. However, per the requirements

of IMI 99-SSPS, a functional test of the SSPS is performed after each

entry into the system controlled by a maintenance request.

The inspector

determined that adequate procedural controls existed for verifying oper-

ability of the reactor trip circuitry.

6.

Surveillance Instruction (SI) Verification

The inspectors reviewed the following sis which implement Technical Specifi-

cation surveillance requirements:

Surveillance Instruction

Title

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Shift Log

SI-2

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SI-3

Daily, Weekly, and Monthly Logs

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SI-6.1

Containment Building Ventilation Isolation

(100 Hr/7 Day)

SI-9

Actuation of Automatic Valves Via SI Signal

for Nontestable Boric Acid and ECCS Flow

Path Valves

SI-12

ECCS Valve Alignment Verification

SI-40

Centrifugal Charging Pump

SI-128

ECCS Residual Heat Removal Pumps

SI-129

ECCS Safety Injection Pump Operability

SI-137.02

Reactor Coolant System - Unidentified

Leakage Measurement

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SI-143

Control Building Emergency Air Cleanup

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System Filter Train Test Requirements

SI-144.1

Control Room Emergency Ventilation Automatic

Actuation

SI-166.10

Accumulator / Injection Primary and Secondary

Check Valve Integrity

SI-166.18

RHR Return Valve Leak Rate Test

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SI-168

Calibration of Control Room Air Intake

Chlorine Detection System

SI-240

Functional Test of Control Room Air Intake

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Chlorine Detection System

SI-256

Periodic Calibration Overcurrent Relays

and Distance Relays on 6.9KV Reactor

Coolant Pumps on 6.9KV Unit Boards

.SI-257

Periodic Functional of RCP Overcurrent

Devices (Refueling Cycle)

SI-258

Inspection of Molded Case and Lower Voltage

Circuit Breakers

SI-266

60 Month Circuit Breaker Inspection

SI-270

Inspection of Molded Case and Lower Voltage

Circuit Breaker Backup Fuses

SI-413

Hydrogen and Oxygen Level for Gas Decay

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Tank

Additionally, the inspectors reviewed the following calibration and

operating procedures:

Il11-92-PRM-CAL

Nuclear Instrumentation Channel Calibration

S01 30.1

Control Building and Control Room Heating,

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Air Conditioning, and Ventilation System

S0I 30.6

Auxiliary Building Gas Treatment System

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As a result of this review, concerns were noted in the following areas:

a.

SI-256, Periodic Calibration of Overcurrent Relay and Distance Relays

on 6.9 kv Unit Boards

TS 3/4.8.3 for operability and surveillance of Electrical Equipment

Protection Devices and Containment Penetration Conductor Overcurrent

Protection Devices was reviewed to determine specific testing require-

ments. Major differences were identified by the inspectors between the

TS requirements for Unit 1 and Unit 2 testing of the primary and

secondary protection devices of TS Table 3.8-1:

(1) For the Unit I reactor coolant pump penetration backup overcurrent

protective devices, the licensee sets the

trip setpoints at

20,000 amps instead of the 2,000 amps specified in TS Table 3.8-1.

Per discussion with the licensee, the backup device trip setpoint

values in the Unit 1 TS were identified to be incorrect, based on

the ncrmal current load through the breaker.

The backup circuit

breaker is the normal feeder breaker for the 6.9 kv unit board.

(2) The Unit 1 and Unit 2 primary device trip setpoint values are

inconsistent.

In the Unit 2 TS, only the instantaneous trip

feature (plunger) of the primary conductor overcurrent protective

device is specified for testing.

The Unit 1 TS requires testing

of only the delayed primary protective device feature (rotating

disc). The inspector determined that the licensee tests both trip

features of the primary protective devices on each unit.

The

location for the Unit 2 reactor coolant pump number 4 primary

and backup devices stated in the TS is PNL-9 on the 6.9-KV

Auxiliary Power Board 2D. The devices are actually located in PNL-7

of that board.

(3) The response time values in TS Table 3.8-1 for the primary

protective devices should have units of minutes instead of

seconds.

(4) These TS errors have existed since initial licensing of both

units.

The licensee submitted TS change request number 62 on

November 7,1984, which proposed deleting TS Table 3.8-1, but did

not address the above errors.

This proposed TS change request is

under NRC review.

The correction of TS Table 3.8-1 is required

prior to unit startup and is identified as an Inspector Followup

Item (327, 328/85-46-02).

Duc to inadequate and incorrect requirements identified in the current

TS Table 3.8-1 described above, the inspectors were unable to determine

if the intent of the TS and plant design were fully met by use of

procedure SI-256. Additionally, the licensee failed to seek correction

of TS Table 3.8-1 :for an inordinate amount of time.

These issues

constitute an Unresolved Item (327, 328/85-46-03) pending further

review of the licensee's testing methodology.

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SI-256 is performed to accomplish the surveillance requirement of TS 4.8.3.1.a.1(a).

The most current completed SI data package for SI-256

(dated October 1,1985) was reviewed by the inspector.

Item (2) in

Section I of the Acceptance Criteria of SI-256 required that the

primary overcurrent relays pickup and critical time are to be within a

tolerance of 5 percent of the trip setpoint values.

However, TS for

Unit 2 primary devices on the reactor coolant pump (RCP) containment

penetrations require a tolerance of 2 percent.

Item (2) also required

that the relay targets operate properly between 1.0 amp and 2.0 amp

with DC voltage applied.

However, the vendor instruction manual for

the General Electric type IAC66K relay indicated proper operation to be

between 0.1 amp and 2.0 amp.

Item (3) in Section I of the Acceptance

Criteria required that the distance relay, impedance circle show the

angle of maximum torque to be close to 75 degrees (phase angle). The

correct angle of maximum torque was actually verified at 105 degrees,

which is the proper value.

These invalid criteria constitute a

violation for failure to adequately establish a surveillance procedure

(327, 328/85-46-04).

As part of the corrective action, the licensee

should determine if this resulted in TS setpoint violations.

Further

examples of inadequate procedures are described elsewhere in this

report.

During the review of the completed Routine Relay Test Record sheets,

the inspector identified that recorded target settings documented

target operation at 0.2 amp.

Item (2) of the acceptance criteria was

signed off and verified by a second person that the 1.0 amp to 2.0 amp

requirement was satisfied, despite the 0.2 amp recorded value.

The

inspector could not ascertain the reason for this discrepancy.

The

inspector also found that the completed SI package had been reviewed

by both the section supervisor and quality assurance (QA).

These

verifications / reviews of the completed SI package and signoffs did not

identify that the acceptance criteria was not satisfied and did not

identify the procedural discrepancies.

This constitutes a violation

for failure to adequately implement the signoff and review provisions

of procedure SI-256 (327, 328/85-46-05). Additionally, several Routine

Relay Test Record sheets in the completed SI-256 data package had

numerous uncontrolled changes made to the Setting Record column

Instrument Setting parameter units.

This was due to the Test Record

sheet being a generic data sheet for all relays.

These procedure

changes were not controlled per AI-4 Plant Instructions - Document

Control for control of procedure changes.

Failure to implement pro-

cedure change requirements of AI-4 is a further example of violation

327, 328/85-46-05.

The licensee should address corrective actions to

ensure that employees understand the need to follow procedures or

properly correct them when technical errors exist.

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b.

System Operating Instruction (S0I) 30.6 for the Auxiliary Building Gas

Treatment (ABGT) system was compared to the as-built configuration of

the plant through inspector walkdown.

The inspection was performed as

a followup to a previous inspection of the ABGT system reported in

Inspection Report 327, 328/85-43.

The inspectors noted that S0I 30.6

specified fuses of a different amperage rating than those that were

actually installed.

This was identified as an Unresolved Item 327,

328/85-43-01 pending review of pertinent system modifications.

In

1984, the licensee approved and implemented Engineering Change Notice

(ECN) L 6278 which modified the ABGTS circuitry for humidity control.

The inspector reviewed S0I 30.6 for compatibility with these ABGTS

modifications.

The procedure was found to be deficient in the

following areas:

(1) The procedure listed vent boards 2B1-B and 2Al-1 as having three

FRS 45 ampere fuses. Fifty ampere fuses were actually installed.

The installed fuses were verified by the inspector to be the

required fuses, based on modifications performed under Engineering

Change Notice (ECN) L 6278 and Work Plan 11326.

(2) The procedure listed vent boards 2B1-B and 2Al-1 as having three

KTN 2 ampere fuses. One ampere fuses were actually installed. The

installed fuses were verified by the inspector to be the required

fuses, based on ECN L6278 and Work Plan 11326.

(3) The procedure prescribed the position of a current block switch

which had been removed from the circuit by ECN L6278 and Work Plan

11326.

Based on these deficiencies, failure to maintain system operating

procedures affected by plant modifications is a further example of

violation 327, 328/85-46-04.

c.

The inspectors selected the same sis at Sequoyah that were found

deficient at the Watts Bar facility during SI review inspections. The

inspection findings at Watts Bar are presented in NRC Inspection

Reports 50-390/84-73, 50-390/85-21, 50-390/85-32, and 50-390/85-51.

The inspectors reviewed seven sis to determine if the deficiencies

identified at Watts Bar existed at Sequoyah.

The sis reviewed were:

SI-3, SI-9, SI-12, SI-40, SI-128, SI-129, and 51-144.1.

Based on the

review of these sis, the inspector determined that the Watts Bar SI

deficiencies were either corrected or did not exist at Sequoyah, with

the exception of SI-12 and SI-144.1.

SI-12 provides instructions for Emergency Core Cooling Systems valve

alignment verification per the surveillance requirements of TS 4.5.2.

This SI did not specify verification of valve position for the two

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automatic flow path valves, LCV-62-132 and LCV-62-133, located at the

outlet of the volume control tank.

The inspector discussed this item

with the licensee and determined that the subject valves are verified

for position by SI-3 during the check of system boration paths.

Furthermore, these valves close upon an ECCS actuation signal.

The

inspector had no further questions.

SI-144.1 controls testing of the Control Room Emergency Ventilation

(CREV) Automatic Actuation feature.

The test objective for this SI is

to verify that on a safety injection signal (SIS), the control room

ventilation system automatically divert air inlet flow through the HEPA

filters and a charcoal absorber bank.51-144.2 requires the same type

of verification by a radiation detector test.

These surveillance

tests must be performed at least once per 18 months as required by

TS 4.7.7.e.2.

Per FSAR Section 9.4, control room isolation occurs

automatically upon actuation of SIS, indication of high radiation, and

either high temperature, chlorine, or smoke concentrations in the

outside air supply to the control building.

Upon actuation, the

control room emergency air cleanup fans will operate in a recirculation

mode through the HEPA filters and charcoal absorbers.

The inspector

found no TS requirement to test the CREV automatic actuation on signals

other than SIS and high radiation.

SI-168, Calibration of Control Room

Air Intake Chlorine Detection System and SI-240, Functional Test of

Control Room Air Intake Chlorine Detection System, do not appear to

test the control room isolation feature on high chlorine. As a result,

all the features that are designed to initiate control room isolation

do not appear to be tested.

Further inspection to ascertain if these

features are tested by the licensee is an Inspector Followup Item (327,

328/85-46-06).

The inspectors also reviewed IMI-92-PRM-CAL, Nuclear Instrumentation

Channel Calibration, and verified that the procedure calls for

independent verification during removal and replacement of instrument

power fuses.

7.

NUREG 1154 (Davis-Besse Event Review)

In response to the NRC findings of the June 9, 1985, Davis-Besse event the

licensee assigned a task team to evaluate the NRC Generic Letter 85-13,

which transmitted NUREG-1154, and an INP0 report entitled "The Operational

Performance of Auxiliary Feedwater (AFW) Systems in U.S. PWRs 1980-1984".

The inspectors reviewed TVA's evaluation of the two documents for the

Sequoyah Nuclear Plant.

TVA's evaluation addressed the significance of the

Davis-Besse loss of main and auxiliary feedwater event with respect to

Sequoyah.

The INP0 report was utilized by TVA to review the Sequoyah AFW

system for problems that have been experienced by other utilities.

The

following nine major topics were evaluated from the Davis-Besse Event:

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a.

Interaction of Plant Security Features and Operator Actions

The inspectors determined that the interaction of plant security

features and operator action problems which occurred at Davis-Besse

would not have occurred at Sequoyah.

At Davis-Besse, the equipment

operators were dispatched to manually open valves and operate the

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turbine-driven AFW pumps in which they had to cope with chained and

padlocked accesses to the pump rooms as well as padlocked manual

handwheels on valves.

For manual control at Sequoyah, the operators

only have to deal with normal card reader doors.

Guards are available

in the vicinity with keys to open doors in the event of failure of the

card readers.

None of Sequoyah's AFW valves or other components are

located in locked high radiation areas, so accesses to the AFW valves

are not required to be locked,

b.

Availability of Shift Technical Advisors (STA)

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An inspector toured the control room for the purpose of observing the

designated work area and availability of the Shift Technical Advisor

(STA).

The Sequoyah STAS have a desk and file space in the main

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control room (MCR), and are generally confined to this area.

The STA

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may leave the MCR to perform his duties provided he can return within

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ten minutes.

The inspector determined that these conditions would

assure that the STA would be available for utilization during an

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operational event such as the Davis-Besse event.

c.

Reliability of the AFW Containment Isolation Valves and Other Safety

Related Valves

Unlike Davis-Besse, Sequoyah's AFW System does not have any motor-

operated (M0) containment isolation valves.

Sequoyah has experienced

reliability problems with other M0V's in the AFW system and failure of

the main FW isolation valves have occurred due to improper limit switch

settings.

The licensee is implementing increased MOV maintenance, and

the Motor-operated Valve and Test System (M0 VATS) is being used.

The inspector observed an operator training session conducted locally

at the Unit 1 Turbine Driven Auxiliary Feedwater Pump.

The licensee

instructor adequately covered:

problems experienced by operators

during the Davis-Besse event, resetting and local operation of the

Turbine Trip and Throttle Valve (TTV), and local operation of the AFW

Steam Generator Level Control Valves. The inspector found that a

laminated sign had been installed near the TTV with a drawing of

the TTV and instructions for local resetting of the TTV following a

mechanical overspeed trip. Discussions held with management indicate

,

that all operators will receive training of a similar nature prior to

startup of either unit.

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The inspector examined the operator requalification training records

and noted that the program contains a requirement for annual simulator

training on a complete loss of feedwater event (normal and emergency).

The records were adequate to demonstrate that the training is being

performed.

d.

Reliability of AFW Pumps

The reliability of AFW pump turbines is not as critical at Sequoyah

as Davis-Besse because of two 100 percent capacity motor-driven AFW

pumps. The AFW reliability is being further improved by the licensee's

implementation of enhancements in response to an INP0 finding.

e.

Reliability of Power Operated Relief Valves (PORV)

Sequoyah surveillance programs provide some assurance of operational

readiness of the Power Operated Relief Valves (PORV).

However, it does

not provide reliability data for repeated openings and closings under

actual slow conditions, when failures have been known to occur.

The

licensee does not support the NUREG-1154 suggested automatic block

valve closure as a potential remedy for PORV failures.

The use of

Automatic block valve closure for isolation of PORV could result in the

use of the code safeties as a pressure relief path. The code safeties,

which have a history of failure to reset could then be subject to the

same multiple openings as the PORV and cannot be isolated,

f.

Adequacy of control room instrumentation

The inspector reviewed control room instrumentation including the

location of the acoustical monitoring instrumentation for detection of

PORV operation / failure.

The acoustical monitoring instrumentation for

both units is located in the common area of the control room, approxi-

mately equal distance from the Unit 1 and Unit 2 controls.

This location will be evaluated by the licensee during the NUREG-0700

control room design review.

The controls, display and location of the

remainder of the control room instrumentation appeared to be accept-

able.

g.

Adequacy of plant procedures

This item was not assessed during this inspection.

h.

Adequacy of safety system testing

The adequacy of safety system testing was assessed from the AFW system

post modification standpoint discussed paragraphs 8.e. and 8.i. of this

report.

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13

1.

Acceptability of current safety assessment methods

This item was addressed in paragraph 7.c. above regarding operator

training on a complete loss of feedwater event and resetting of the

Turbine Trip and Throttle Valve.

Based on the above reviews, the team concluded that licensee actions in

response to Generic Letter 85-13, combined with their AFW Reliability

Improvement Program, exceeded regulatory requirements.

8.

Design Changes and Modifications

Selected design changes were reviewed to ensure that the submitted and

implemented changes were in accordance with 10 CFR 50.59 requirements and

that licensee technical reviews were adequate. The inspectors verified that

design changes were reviewed and app (roved in accordance with Technical

Specifications and Quality Assurance QA) controls, that post modification

tests were performed when necessary, that adequate licensee record and

review functions were performed, that operating and surveillance procedure

revisions were made and approved in accordance with Technical Specifica-

tions, that operator training programs were revised, that cperator training

occurred prior to system startup for significant design changes to safety

related systens, that as-built drawings were changed to reflect the modifi-

cations, and that the required 10 CFR 50.59 annual report to the NRC

included those modifications audited.

Administrative Instruction, AI-19 (Part IV), Plant Modifications After

Licensing, describes the method for implementing all facility modifications.

Per AI-19 requirements, the Work Plan (WP) package includes such items as

the affected engineering drawings, Field Change Request Engineering Change

Notice (ECN) or Design Change Request (DCR) that authorizes the modifica-

tion, applicable Modification and Addition Instructions (M&Als), appropriate

work permits (e.g., breeching of fire barriers, concrete chipping), material

traceability forms, and post maintenance testing results. The selected Work

Plan packages were reviewed for compliance with the requirements of AI-19

by the inspectors.

The modification packages reviewed were applicable to

changes made in the instrumentation system, reactor coolant system, emer-

gency core cooling system, containment system, and the auxiliary feedwater

system.

The selection of these modification packages was based on a review

of the licensee's annual 10 CFR 50.59 report submittal for 1984, dated

March 15, 1985.

This submittal included a summary of all facility changes

which the inspectors used to select modification packages for review.

In

addition, the inspectors reviewed modification packages that were completed

in 1985.

The following ECNs, DCRs, and Design Modification Work Plan (WP) packages

were reviewed:

a.

ECN L 5600, which included WPs 9598, 9519, and 9518, modified the

activating system for automatic switchover of Residual Heat Removal

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system suction from the Refueling Water Storage Tank to the containment

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sump to improve reliability.

b.

ECN L 6055, which included WP 10766 was established to install cold

over pressure protection (COP) circuitry in the Solid State Protection

System racks.

c.

ECN L 5093, which included WPs 9980, 11378, and 9969 was established to

install drain and block valves for containment isolation valve penetra-

tions to allow local leak rate testing with air.

No post modification

testing was required for this modification. Many of these valves have

exhibited leakage which has affected local leakrate testing results.

d.

ECN L 2780, which included WP 9516, was established to install reactor

shield building penetration sleeves to support Post Accident Sampling

System installation.

e.

ECN L 5342, Post Modification Test (PMT) 53, was conducted on Unit 1 to

test the Auxiliary Feedwater (AFW) System Cavitating Venturis installed

urder WP 10920.

PMT 53 was performed to verify that the venturis would

prevent pump runout, that the piping vibration levels were acceptable,

and that the AFW Pump would deliver 440 gpm at 400 psia S/G pressure

through the AFW bypass level control valve without motor overload.

Test Instruction Deficiency Report DN-2 for Unit 1 was written because

the piping vibration data did not meet the vibration acceptance

criteria of SQN-DC-V-13.13.

The deficiency was dispositioned by

preloading piping hanger 1AFDH-345.

The preload of the hanger reduced

the vibrations to acceptable levels.

For Unit 2, test deficiency DN-3 identified that vibration exceeded the

acceptance criteria in the Y-axis where displacement was 250 mils zero

to peak versus acceptable displacement of 219 mils.

This deficiency

was noted at full flow conditions and less than 100 psig in the steam

generator.

For corrective action the disposition stated that pump

operation above 440 gpm should be limited to reduce the detrimental

effects of downstream vibration to prevent hanger and instrument line

damage.

The adequacy of the design is questionable since the purpose

of the venturi is to protect the AFW pump from runout damage up to a

,

maximum of 650 gpm flow, and the Technical Specification bases require

the pump to provide no less than 440 gpm.

At the time of inspection

insufficient data was obtained to show at what flowrate vibration

levels were acceptable.

This is identified as an Unresolved Item (327,

328/85-46-07) pending further information from the licensee,

f.

ECN L6285, which included WP 11360, was established to replace the

motor operator of component cooling water system isolation valve

2-FCF-70-87 with an environmentally qualified actuator per NUREG-0588.

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g.

ECN L5883, which included WP 11005, was established to replace and

relocate flow and pressure switches at penetration room cooler fans in

order to meet NUREG-0588 requirements.

h.

DCR 775, which included WP 10183, was utilized to replace existing

Solid State Protection System block handswitches (HS-63-135A,135B,

136A, and 136B).

i.

ECN L 5490, which included WP 9360, was utilized to relocate the Unit 2

Terry Turbine control panel due to temperature effects on the panel.

This package control form did not contain signatures to document

completion of drawing revisions, or a signature for review for

Technical Specification impact by an SR0. The package appeared to be a

reconstruction of a lost original work package.

.

Minor discrepancies were identified during the review of Work Plans

described in paragraphs 8.a. , 8.c. , 8.d. and 8.f. of above. These discrep-

ancies included such items as an incomplete nameplate data form, failure to

include material traceability information, lack of signatures, and unavail-

able engineering justification for such items as severing of reinforcing

bars when making a penetration through a shield wall or using TVA standard

hanger configuration for modification requiring installation of additional

valves.

The inspectors noted that the licensee was cognizant of similar

deficiencies prior to this inspection and had made revisions to the

controlling plant modification procedure AI-19 (Part IV).

For example,

"

AI-19 (Part IV), Revision 11 dated August 22, 1985, added instructions

to document material purchased (i.e. material traceability), added the

requirement for the Shift Engineer to make a configuration log entry when

equipment is removed from service due to a modification, and included a

checklist to ensure that the package is complete.

AI-19 (Part IV),

Revision 12, provided, in part, a requirement to verify that all affected

instructions have been revised. Most of the discrepancies identified by the

inspectors were in Work Plan packages completed prior to the implementation

of AI-19 (Part IV), Revisions 11 and 12.

Therefore, the inspectors have

concluded that the licensee has taken positive steps in improving admini-

strative control of modification packages.

The inspectors also reviewed the licensee's program for temporary modifica-

,

tions, lifted leads, and jumpers.

The following deficiencies were

'

identified:

a.

Approximately 200 temporary alterations are currently active for

'

Sequoyah Units 1 and 2.

This number appears to strain the administra-

tive control system effectiveness.

Step 3.1 of AI-9 requires that

where practical, plant management shall initiate a design change

,

request (DCR) or field change request (FCR) in accordance with AI-19 to

eliminate the need for temporary alterations.

Although a management

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action tracking system requires routine review for the purpose of

determining justification for continued need, many temporary altera-

.

tions over three years old are still in place.

Discussions held with

licensee employees indicated that the licensee has committed as the

result of an INP0 audit to clear all temporary alterations made prior

to January 1,1984, before startup following completion of Unit 1

cycle 4.

This is identified as an Inspector Followup Item (327,

328/85-46-08).

b.

No adequate system appears to exist to ensure that post modification

testing is accomplished during restoration of temporary modifications

that do not result in permanent modifications. This has been corrected

for recent temporary alterations, but not addressed for older altera-

tions.

Revision 19 of AI-9 requires that retesting requirements be

identified on the Temporary Alteration Control Form, but the inspector

was unable to determine if long term temporary modifications are covered

by this requirement.

This is identified as an Unresolved Item (327,

328/85-46-09) pending further review of the licensee's program.

9.

Operating Experience Review

The inspectors review of the Nuclear Operations Experience Feedback Program

consisted of a review of Standard Practice SQA-26 and training documents,

and discussions with licensee personnel.

Additionally, Watts Bar Nuclear

Plant's Standard Practice WB6.3.13, Nuclear Operations Experience Review

procedure, was used for comparison.

The inspectors found that some duplication existed in the routing of lessons

learned materials to different sections.

The inspectors reviewed the

modifications performed during Units 1 and 2, cycle 2 refueling outages.

Selected modifications which affected plant operation from the control room

were traced through the training process to ensure that the operations staff

was trained prior to plant startup.

For the cases reviewed, appropriate

training was provided prior to plant startup.

Implementation of the

operating experience feedback program was considered above average by the

team.

10. Westinghouse Setpoint Methodology Verification

The Westinghouse Setpoint Methodology (WSM) for the Sequoyah Nuclear Plant

(SQN) established the appropriate margin between the actual Technical

Specification setpoints used for reactor protection system instrumentation

and the setpoints required to meet the Technical Specification safety

limits.

The margin is calculated by conservatively estimating the errors

.

associated with the reactor protection system instrumentation and actuation

'

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of the protection equipment.

One of the sources of error evaluated was the

!

accuracy of the Measuring and Test Equipment (M&TE) used to calibrate the

reactor protection system instrumentation.

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On April 15-19, 1985, an NRC inspection at Watts Bar Nuclear Plant (WBN)

identified that certain inconsistencies existed between the calibration

accuracy of the M&TE used to calibrate Solid State Protection System (SSPS)

equipment and the accuracy of the M&TE assumed in the WSM. These inconsis-

tencies were such that the safety margins for at least two parameters

!

at Watts Bar (WBN), including containment pressure, were in doubt.

The

licensee's review of this discrepancy identified that Sequoyah Nuclear Plant

was potentially affected.

Information on the inconsistencies between the

4

WSM and the calibration M&TE used at WBN was provided to the SQN staff at a

meeting with SQN, WBN, and Westinghouse on May 7, 1985.

a.

Accuracy of Measuring and Test Equipment (M&TE)

.

The incorporation of the WSM into the calibration procedures for the

SQN Solid State Protection System (SSPS) was evaluated.

The WSM

'

assumed that the M&TE had an accuracy of ten times that of the equip-

ment being calibrated.

The WSM referenced a Scientific Apparatus

Manufacturers Association (SAMA) document entitled " Process Measurement

and Control Terminology", which described the required M&TE accuracy.

The incorporation of this M&TE accuracy standard allowed the enginee-

ring calculation of inputed error to the sensor calibration accuracy to

be estimated by Westinghouse.

(The actual values of the different

i

error categories and the error categories are themselves proprietary

data and will not be discussed in this report.)

Setpoints based on the WSM were incorporated into the SQN surveillance

and calibration programs.

Several pieces of M&TE used at SQN do

not achieve the ten to one accuracy requirement assumed in the WSM.

Examples of this equipment include instruments used to provide current

inputs such as the Fluke 8600, Keithly 197 and 175, and instruments

used to provide pneumatic inputs such as the Heise 711B and Ashcroft

Digigage.

These pieces of M&TE are used at SQN to calibrate and

functionally test the SSPS instrumentation.

Technical Specifications (TS) require that written procedures shall be

established, implemented, and maintained covering TS surveillance and

2

test activities or safety related equipment.

Instrument Maintenance

Instruction IMI-99, Reactor Protection System, was established to

implement these requirements for the calibration and functional testing

of the Solid State Protection System. TS 6.5.1.6 states that the Plant

Operations Review Committee (PORC) shall be responsible for the review

of all TS required procedures and changes thereto.

'

The calibration procedures of IMI-99 were inadequately established

since they did not reflect the assumptions of the methodology study

and did not justify the technical adequacy of the deviation from the

methodology. This is a further example of violation 327, 328/85-46-04.

Other calibration and functional testing procedcres in addition to

IMI-99 may be affected by the failure to incorporate this requirement.

The licensee has committed to identify and correct these procedures.

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b.

Calibration of Containment Pressure Transmitters

The SQN containment pressure transmitters (Barton 764) were previously

removed from Watts Bar Nuclear Plant (WNP) and sent to SQN for replace-

ment of two non-environmentally qualified Foxboro transmitters.

The

Barton transmitters were installed under Work Plan 11554, which was

approved by PORC on March 30, 1985, and completed on April 3,1985.

After the May 7,1985 licensee methodology meeting, a contract with

Westinghouse was established for Watts Bar to determine the effect of

the incorporation of the actual M&TE accuracy on the calibration of

reactor protection system instrumentation to meet the WBN safety limit

margins.

Preliminary calculations, received by WBN and SQN about

July 3,

1985, indicated that the containment pressure instrument

calibration would result in values that were outside both the Technical

Specification setpoint and the Technical Specification safety limits

when the reduced accuracy of the M&TE was included.

Informal calculations were performed by the SQN compliance staff about

July 8, 1985, which incorporated actual observed values for other

parameters, including setpoint drift, rather than the conservative

values assumed in the WSM. These calculations demonstrated that, based

on the actual historical error values for certain parameters at SQN,

including the M&TE, the setpoint was within the safety limit.

Based on this calculation, the licensee concluded that there was no

engineering concern; however, the licensee failed to recognize and

promptly evaluate the potential failure to meet the Technical Specifi-

cation limits based on the potential error of reactor protection

instrumentation as determined by the design basis document,

i.e., the

WSM.

In addition, the calculations made were informal and reviewed and

formally approved by only one level of plant management.

During this

informal review, the licensee also determined that the original WSM for

SQN had a negative safety margin for containment pressure. This is an

inspector followup item (327, 328/85-46-11).

Technical Specifications require that the Plant Operations Review

Committee (PORC) to review unit operations to detect potential nuclear

safety hazards and to investigate all violations of the Technical

Specifications.

A formal PORC review was not performed after addi-

tional information was received by the licensee, including PORC

members, about July 3,1985, which indicated that the calibration of

the Barton containment transmitters could be outside the technical

specification safety limits.

The licensee continued to operate both

units at full power until late August 1985 without formally reviewing

this potential nuclear safety hazard.

The safety significance of the

overall setpoint methodology issue also was not formally reviewed and

resolved by PORC.

Failure to conduct required PORC reviews constitutes

a violation (327, 328/85-46-10).

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c.

Licensee Actions to Evaluate M&TE Accuracy

SQN established a contract with Westinghouse in September 1985 to

determine if safety limits were exceeded based on the actual accuracy

1

of M&TE used at SQN.

The licensee expects to have preliminary results

j

for the following three areas in January 1986:

Nuclear Instrumentation System RCS Delta Temperature and Average

Temperature M&TE accuracy ratios

Transmitter and rack M&TE accuracy ratios

Containment Pressure Transmitters accuracy ratios

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Until the results of this evaluation are available, adequacy of the

current reactor protection as-left setpoints is an Unresolved Item

(327,328/85-46-12).

In summary, throughout this methodology issue, the inspection found that SQN

!

management failed to take positive actions to establish that safety limit

'

margins and setpoints met license requirements despite the known Watts Bar

deficiencies.

11.

Reactor Trip Reduction Program

4 .

The inspector reviewed Sequoyah's Reactor Trip Reduction Program.

The

licensee's program consisted of an evaluation of the areas identified in

.

INP0's " Scram Reduction Practices", INP0 85-011. This evaluation was issued

j

in a November 21, 1985 report on scram reduction practices at Sequoyah. The

report addressed in detail each of the INP0 items and identified which were

being implemented and which were standard practice.

!

The licensee identified 27 trips which have occurred since January 1, 1984

!

on Sequoyah Units 1 and 2 in a transmittal letter stating their actions to

meet 10 CFR 50.54(f) commitments. The 27 trips were placed in one following

four categories.

!

Equipment Malfunctions or Failures

13 trips

i

Manual Feedwater Control of Steam Generator (S/G)

8 trips

!.

Personnel Error

5 trips

,

Inexperience with Auto-Bypass Controller

1 trip

i.

for S/G Feedwater Bypass Regulating Valve

!

The root causes of the 13 trips were identified and long term corrective

actions taken consisting of preventative maintenance, design reviews and

posting of warning signs to prevent reoccurrence for five trips.

No long

term corrective action was felt appropriate for the remaining eight trips.

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The licensee preventative maintenance program consisted of:

Critical plant equipment which can cause scrams is inspected and tested

during each refueling outage.

Vendor simulators are used for testing systems.

Preventative maintenance on important equipment is minimized while

plant is operating.

I&C technicians verify that control systems are functioning properly by

stroking components through their full range.

Major equipment performance is monitored so anticipatory corrective

action can be taken prior to a scram.

I

A design change to install automatic control of feedwater bypass regulating

valves was installed to reduce the trips which occurred from manual control.

Additional feedwater system modifications were made as a result of the

Davis-Besse event which will improve the AFW system reliability.

The licensee is implementing additional training to reduce personal errors.

I&C technicians receive a half day of systems training per week as part

of the continuing training programs.

Simulator training is provided for I&C technicians, engineers, and

certain maintenance personnel based on availability of simulator.

Newly hired technicians must complete a certification program that

includes procedures, policies, system training and practical factors.

Certification must be completed satisfactorily prior to performing

unassisted testing.

On-the-job training is conducted by a foreman as part of the training -

i

qualification process.

Vendor training programs are used for critical plant equipment (e.g.,

EAC, governors, motor operated valves).

Operations personnel receive training on plant modifications prior to

placing new equipment in service.

,

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Trainees, including available auxiliary operators, observe and in some

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cases, receive hands-on experience during the plant evolutions, such as

start-up, synchronization and shutdown in the control room.

Operations personnel are given addition in-depth training on balance of

plant equipment.

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Emphasis is placed on promoting operators up through the ranks from

entry-level positions.

The licensee has also implemented the following practices to reduce plant

trips.

A system engineer is assigned for each plant system.

His responsi-

bilities include the following:

reviewing and trending surveillance test results

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recommending preventative maintenance

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coordinating all design changes

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writing procedures and design changes

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reviewing all maintenance on the system, conducting

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post-maintenance testing and assisting in troubleshooting

The Shift Technical Advisors perform a comprehensive post-trip review

to determine the root cause and the correction of the cause for each

scram.

The Shift Supervisor and Shift Engineer perform a joint review after a

scram and an unusual occurrence report is prepared.

A committee of

operations, maintenance, engineering is convened to investigate the

event.

The group reviews data and interviews personnel to determine

the causes of all failures or unusual occurrences for the implementa-

tion of corrective actions.

Plant startup does not commence until all reviews are complete.

The

superintendent or Assistant Superintendent must give the approval to

restart the plant.

A historical data base is maintained to allow analysis and trending by

scram cause codes.

,

The licensee is a member of the Westinghouse Owners Group which has a

'

program for investigating each scram.

Since the majority of scrams are caused by problems in the Balance-

!

of-Plant (B0P) systems, a licensee procedure requires that the same

case is exercised in surveillance, maintenance, operation and

engineering of B0P systems as is in the NSSS systems.

The licensae has implemented numerous other procedure changes,

personnel training and equipment modifications not addressed in this

report.

The licensee was also pursuing improved reliability and trip reductions by

other programs, such as the task force identified AFW system action items

discussed in the Davis-Besse section of this report.

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The actions being taken by the licensee indicated an adequate effort to meet

the 10 CFR 50.54(f) commitments made in their letter dated November 1,1985,

and to improve plant reliability through trip reduction.

The inspector verified licensee implementation of steps taken to reduce the

number of reactor trips on a sampling basis and held discussions with the

training department and operations personnel on this subject matter.

The

inspector concluded that the licensee has taken positive steps to improve

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plant reliability.

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