ML20138Q402

Insp Repts 50-369/85-40 & 50-370/85-41 on 851029-1120. Violation Noted:Surveillance to Verify Operability of Refueling Canal Drains & PORV Block Valves Not Performed within Applicable Surveillance Intervals

ML20138Q402
Person / Time
Site:	Mcguire, McGuire
Issue date:	12/13/1985
From:	Dance H, William Orders, Pierson R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20138Q380	List: ML20138Q378 ML20138Q384 ML20138Q402
References
50-369-85-40, 50-370-85-41, NUDOCS 8512270184
Download: ML20138Q402 (10)

See also: IR 05000369/1985040

Text

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UNITED STATES

ppMilog*o . NUCLEAR REGULATORY COMMISSION

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o REGION 11

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. ,, j 101 MARIETTA STREET.N.W.

3 ATi.ANTA.cEcac A sos 2s

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Report Nos: 50-369/85-40 and 50-370/85-41

Licensee: Duke Power Company

422 South Church Street

Charlotte, NC 28242

Facility Nan; : McGuire Nuclear Station

Docket Nos: 50-369 and 50-370 License Nos: NPF-9 and NPF-17

Inspection at McGuire Nuclear Station near Huntersville, North Carolina.

Inspectors: b A^-- k

W.' Orders,~ Senior Resident Inspector

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Dat6 Sicfned

R. Pi

W W

son, Resident Inspector

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0ath Sigfied

Approved by: b $+ e / /3 f

Hugh C// Dance, Sectibn Chief Dath Si@ned

Division of Reactor Projects

SUMMARY

Inspection on October 29, 1985 through November 20, 1985.

Scope: This routine unannounced inspection involved 200 hours0.00231 days <br />0.0556 hours <br />3.306878e-4 weeks <br />7.61e-5 months <br /> onsite n the

areas of operations, surveillance testing and mainten e ce activities.

Results: Of the areas inspected, one violation was identified in the area of

surveillance testing.

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REPORT DETAILS

1. Persons Contacted

Licensee Employees

• T. McConnell, Plant Manager

• B. Travis, Superintendent of Operations

• D._ Rains, Superintendent of Maintenance

• B. Hamilton, Superintendent of Technical Services

• L.-Weaver, Superintendent of Administration

• M.' Sample, Superintendent of Integrated Scheduling

• E. McCraw, License and Compliance Engineer

D. Mendezoff, License and Compliance Engineer

D. Marquis, Performance Engineer

R. White, IAE Engineer

R. Branch, Site QA Supervisor

Other licensee employees contacted included construction craftsmen,

technicians, operators, mechanics, security force members, and office

personnel.

• Attended exit interview.

2. Exit Interview

The inspection scope and findings were summarized on November 26, 1985, with

those persons indicated in paragraph 1 above. The violation discussed in

paragraph 12 was acknowledged. The licensee did not identify as pro-

prietary any of the materials provided to or reviewed by the inspectors

during this inspection.

3. Licensee Action on Previous Enforcement Matters

No previous enforcement items were closed.

4. Unresolved Items *

Two unresolved items were identified during this report period and are

discussed in paragraphs 11 and 13.

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5. Plant Operations

The inspection staff reviewed plant operations during the report period, to

verify conformance with applicable regulatory requirements. Control

operator logs, shift supervisors logs, shift turnover records and equipment

removal and restoration records were routinely perused. Interviews were

• An Unresolved Item is a matter about which more information is required to

. determine whether it is acceptable or may involve a violation or deviation.

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conducted with plant operations, maintenance, chemistry, health physics, and

performance personnel. Activities within the control room were monitored

during shifts and at shift changes. Actions and/or activities observed were

conducted as prescribed in applicable station administrative directives.

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The complement of licensed personnel on each shift met or exceeded the

minimum required by technical specifications (TS).

Plant tours taken during the reporting period included but were not limited

to the turbine buildings, auxiliary building, Units 1 and 2 electricci

equipment rooms, Units I and 2 cable spreading rooms, and the station yard

zone inside the protected area. During the plant tours, ongoing activities,

housekeeping, security, equipment status and radiation control practices

were observed.

Unit 1 Operations Summary

Unit I began the reporting period in Mode 1 operating at 100% power and

remained at that power level until November 2,1985. At 6:40 a.m. that

morning, with both units operating at 100% power, the flexible discharge

line of Instrument Air Compressor B failed resulting in the loss of

instrument air en both McGuire units. The loss of instrument air resulted

among other things in the pneumatic main feedwater regulator valves

drifting closed on both units, ultimately resulting in reactor trips on both

units due to lo-lo steam generator level. A safety injection occurred on

Unit I but did not occur on Unit 2 as system pressure did not decrease to

the. initiating setpoint.

The safety injection on Unit I required the declaration of an Unusual Event.

The declaration was made at 7:25 a.m., that morning and was terminated at

9:04 a.m. The unit was restarted later that day and remained in Mode 2

pending repair of a severed instrume'nt fitting on the secondary side of the

"A" Steam Generator. Efforts to repair the instrument fitting in Mode 2

were futile. It was decided to place the unit in a status more conducive to

the repair, thus the unit was placed in Mode 3 at 12:55 p.m., on November 3

and was subsequently cooled down to 360 degrees F and 1600 psig.

On Monday, November 4, 1985, the instrument fitting was repaired but a

through wall leak on the "D" Steam Generator feedwater check valve was

detected. The unit was cooled down and placed in Mode 5 at 8:08 a.m., on

November 6,1985, to facilitate the necessary valve repairs. Following the

completion of the repairs, the unit was returned to the grid at 10:34 a.m.,

on November 9. That afternoon power ascention was terminated due to high

containment temperature which resulted when 1 of 3 operable Containment

Cooling units was lost. Power was reduced to 10% to facilitate repairs to

the cooling unit and was subsequently increased to 100%.

.cx unit remained at full power until November 20, when a unit runback

occ;rred due to a main feedwater pump trip. The remaining main feedwater

pump was i nable to maintain the required flow, began to oscillate, and

ultimately : ripped on high discharge pressure. The trip of the remaining

feed pump caused a turbine trip and reactor trip. All systems responded

normally following the trip. The unit completed the reporting period in

preparation for unit startup.

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Unit 2 Operations Summary

Unit 2 began the reporting period in Mode 1 operating at 100*4 power arid

remained at that power level until November 2 when the reactor tripped as

discussed in the Unit 1 Operations section. A unit fast recovery was

initiated with the unit reaching 100% power at 4:05 p.m., on November 3. The

unit remained at 130% power for the duration of the reporting period.

6. Surveillance Testing

-The surveillance tests below were analyzed and/or witnessed by the inspector

to ascertain procedural and performance adequacy and conformance with

-applicable Technical Specifications. The selected tests witnessed were

examined to ascertain that current written approved procedures were

available and in use, that test equipment in use was calf brated, that test

prerequisites were met, system restoration completed and test results were

adequate.

PT/1/A/4204/01A Residual Heat Removal Pump 1A Perforr Ence Test

TT/1/A/9100/102 Service Water Train IA Flowrate Comparision

PT/1/A/4209/03P NV Valve Stroke Timing shutdown

PT/2/A/4600/03E Refueling Canal Drain Operability Checklist

PT/2/A/4252/01 Auxiliary Feedwater Performance Pump Test #2

.PT/2/A/4252/01A

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Motor Driven Auxiliary Ft.eowate! Performance

Test 2A

PT/2/A/4252/01B Motor Driven Auxiliary Feedwater Performance

Test 2B

7. Maintenance Observations

The maintenance activities below were analyzed and/or witnessed by the

- resident inspection staff to ascertain procedural and performance adequacy

and conformance with applicable Technical Specifications. The selected

activities witnessed were examined to ascertain that where applicable,

current written approved procedures were available and in use, that

prerequisites were met, equipment restoration completed and maintenance- -

results were adequate.

042811 PM/PT Channel Source Checks on all EMF's

56944 Boroscope Containment Heat Exchanger Tubes

126002 SSF Diesel

048176 #2 Auxiliary Feedwater Motor Driven Pump

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8. Vital Battery Technical Specification

On October 3, 1985, Operations personnel determined that the method in which

they performed OP/0/A/6350/01A (125 VDC/120 VAC Instrument and Control

Power) did not meet the intent of TS 3.8.3.1 as follows. To remove a

battery from service for the purpose of an equalizing charge, Operations

personnel performed OP/0/A/6350/01A, Enclosure 4.11. The procedure requires

placing the.120 VAC power on regulated power supply, removing the associated

static inverter from service, closing the tie breakers between the DC

distribution centers and then opening the breaker between the battery and

. the DC distribution center. The battery is then logged in the Technical

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Specification Action Item Logbook as a 72-hour action item.

The 120 VAC Vital Instrumentation and Control Power System receives its

_ normal power from separate independent inverters. A regulated power supply

is provided as an alternate non-essential source for one AC vital load for a

maximum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> per TS 3.8.2.1.

Consequently, unless the provisions of Action b. of TS 3.8.2.1 are met, in

that the associated bus is energized with an operable battery bank via an

operable tie breaker within two hours, the TS allow the use of a regulated

. power supply as an alternate non-essential source for only 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> versus

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the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> as implemented by proceaure OP/0/A/6350/01A. Since

OP/0/A/6350/01A allowed up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> without specifying the provisions of

Action b. o f TS 3.8.2.1, this does not meet the intent of TS 3.8.3.1.

Inasmuch as this was licensee identified, was a Severity Level IV, was

. reported and corrected promptly and was not a violation that could reason-

ably be expected to have been prevented by the licensee's corrective action

for a previous violation, a notice of violation will not be issued.

9. Valve Mislabeled -

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On August 12, 1985, it was discovered that valve 2RN-886 was listed as

2RN-866 in' procedure PT/2/A/4200/02A (Monthly Containment Integrity

Verification) and PT/2/A/4200/02C (Containment Integrity verification During

Core Alterations). The error was discovered during a review of

PT/0/B/4700/23 (Semi-Annual Outside of Containment Locked Valve Verifica-

tion). Upon discovery, 2RN-886 was verified to be locked closed as

required. Valve 2RN-886 is located on the Nuclear Service Water (RN)

non-essential header containment penetration (M307). This valve is also

capped when not in use. Although this incident is indicative of an

inadequate procedure, the NRC encou ages licensee self-identification and

correction of problems through systematic reviews such as those conducted to

find this error. Pursuant to the stipulations of 10 CFR Part 2 Appendix C

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Section V.A., a notice of violation for an inadequate procedure will not be

issued.

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10. Lost Work Request

On October 14. 1985, it was determined that the TS required monthly source

check surveillance on all Unit 2 EMF's (Process and Area Radiation

Monitoring Device) performed on May 19, 1985, would have to be classified as

missed surveillance due to the loss of the documentation. The monthly

surveillance performed prior to and after this event showed that the EMFs

met the functional specifications. To prevent this type incident from

re-occurring, the licensee plans to implement a Maintenance Management

Procedure 4.3. (Lost Work Request), to address this issue. In addition,

the planning section will reevaluate the work request routing system,

looking for improvements for control and transfer between groups and will

evaluate the method of keeping work requests and all associated documenta-

tion together. Although the event qualifies as a missed surveillance,

pursuant to the stipulations of 10 CFR 2, Appendix C, Section V. A., a notice

of violation for failure to meet the surveillance interval specified in

TS 4.3.3.8 and 4.3.3.9 will not be issued.

11. Evaluation of Delta T Incident

Background

During the course of Cycle 2, McGuire Unit 2 has experienced a gradual

decrease in the indicated value of the full power Delta T across tne core.

In the latter part of June, approximately six weeks after power escalation

commenced for Cycle 2, station personnel performed a precision heat balance

to verify RCS (Reactor Coolant System) flow. During this six-week time

frame, the indicated Delta T had decreased by approximately 1 degree F. The

precision heat balance indicated an increase in RCS flow from Cycle 1 and a

corresponding decrease in the measured full power Delta T's for the four

loops. Because the Delta T channels for the overtemperature Delta T and

overpower Delts T setpoints were scaled to the full power Delta T's obtained

.during the Cycle 1 precision heat balance, the Delta T channels were

underpredicting core power by as much as 5% RTP (Reactor Thermal Power).

Station personnel contacted the Safety Analysis Unit to determine whether

the allowable values fo, the overtemperature Delta T and overpower Delta T

setpoints had been exceeded. In addition, they requested guidance as to

what corrective actions should be taken related to the apparent non-conser-

vative indication of power in the Delta T channels. It was mutually agreed

upon the+ the Delta T channels should be rescaled to the Delta T values

obtainec from the most recent precision heat balance. On June 27, 1985, -

station personnel rescaled the Delta T channels to the more conservative,

lower values of Delta T obtained from the June precision heat balance.

However, because of some peculiarities related to the drift of the Delta T

channels, it was difficult to determine whether the overtemperature Delta T

and overpower Delta T setpoints had exceeded their allowable values. On

July 2, 1985, a letter was sent to Westinghouse requesting their assessment

of the causes and licensing implications of the drift in the Delta T

channels.

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The results of the Westinghouse evaluation identified two potential causes

for the Delta T decrease; a change in the hot leg temperature streaming

pattern and/or a reduction in thermal power. Based upon an extensive

evaluation of key plant parameters, Westinghouse concluded that the maximum

error due to changes in hot leg temperature steaming pattern is limited to

0.5 degree F. Some secondary plant parameters indicate that up to

0.5 degree F of the Delta T reduction may be due to a decrease in thermal

power,.possibly caused by fouling of the feedwater venturis.

-The Westinghouse evaluation stated that the approximately 1 degree F drift

associated with the Delta T channels is within the uncertainty allowances

assumed in the safety analyses. Therefore, the precision heat balance

performed in June may be considered valid. In addition, since the error

associated with the calculated flow is within the uncertainty allowance

assumed in the safety analyses, there are no flow related technical

specification violations associated with the Delta T drift incident.

However, when ~ the 1 degree F drift is added to the errors associated with

not calibrating the Delta T channels during startup, the total error

associated with the Delta T channels is greater than the uncertainty

allowances assumed in the safety analyses. Prior to the June 21, 1985,

calibration of the Delta T channels, these errors were as follows:

Loop A Lopp B Loog_C Loop D

B0C 1 Delta T 57.4 57.8 59.8 58.1

6/21/85 Delta T 55.97 54.73 56.53 56.12

Error in Degree F 1.43 3.07 3.27 1.98

Error in % full power 2.5 5.3 5.5 3.4

'These Delta T channel errors can potentially impact the FSAR accidents which

take credit for a reactor trip on the overtemperature Delta T or overpower

Delta T trip functions. There is s'ufficient margin included in the over-

temperature Delta T setpoint calculation to account for the Delta T channel

errors. Therefore, the accident analyses which take credit for a reactor

trip en overtemperature Delta T (RCCA Withdrawal at Power, RCCA Misalign-

ment, and Boron Dilution) remain valid. However, for the overpower Delta T

trip function, there is not sufficient margin in the setpoint calculation to

account for the Delta T channel errors.

Several Technical Specification problem areas were encountered, including

unit consistency in the overpower and overtemperature Delta T expressions,

application of maximum setpoint variation from the computed trip setpoint,

and TS implication that rescaling should take place each time a precision

heat balance is performed. In some instances McGuire appeared to be less

conservative than recommended, and in one appeared to be more conservative.

This issue will be maintained as an Unresolved Item (370/85-41-01) pending

qualified evaluation of Westinghouse's analysis and subsequent evaluation of

this incident as it affects McGuire.

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12. Failure to Perform Technical Specification Surveillance

On October 22, 1985, at 1:20 P.M. , Operations personnel discovered that

Enclosure 13.2 (Refueling Canal Drain Operability Checklist) of PT/2/A/

4600/03E (Quarterly Surveillance Items) had not been completed for Unit 2 by

its latest due date of October 18. The refueling canal drains are required

to be operable in Modes 1 through 4. The procedure was subsequently

performed and successfully completed at 1:45 p.m. that afternoon.

During'the licensee investigation of the incident, they discovered that the

Unit 2 PORV (Pressure Operated Relief Valve) block valve operability test

(Enclosure 13.1 of PT/2/A/4600/03E) was performed on October 21, three days

after its latest due date of October 18. The PORV block valves are required

to be operable in Modes 1 through 3.

A review of the incident with respect to the root cause revealed that an

Operations Engineer in charge of scheduling Operations periodic tests

reviewed PT/2/A/4600/03E, which had been completed on June 25. He

-incorrectly assumed that the PT performed on June 25 met the requirements

for the entire quarter (April 21 through July 21), and the next due date

would be October 21, or three months from July 21. The correct due date for

the PT was September 25 or three months from its last completed date of

Jule 25.

On October 21, control room personnel completed Enclosure 13.1 of PT/2/A/

4600/03E (PORV Block Valve Operability Checklist) but did not complete

Enclosure 13.2 (Refueling Canal Drain Operability Checkli st) . On

October 22, Operations shift personnel turned the procedure over to the

Operations PT group, stating that the shift did not have time to perform

the PT. The assistant shift supervisor in charge of the PT group contacted

the Operations Engineer to find out how much grace time there was left on

the surveillance. It was at this point that the Operations Engineer

detected his mistake.

It was not discovered until later, during the investigation on the refueling

canal drains, that the PORV-block valves had been technically inoperable

from' October 18 to October 21 when Enclosure 13.1 of the PT was completed.

The same Operations shift was on duty on October 21 and 22. The shift

supervisor initialed the procedure step verifying Enclosure 13.2 (Refueling

Canal Drain Operability Checklist) was completed and signed the procedure as

being completed on October 22. The shift supervisor also made log entries

-into the shift supervisor's logbook concerning the missed surveillance on

the refueling canal drains but no entry was made concerning the PORV block

valves.

Contrary to TS 3.6.5.8 and 4.4.4.2, the surveillance to verify the

operability of the refueling canal drains and the PORV block valves were not

performed within their applicable surveillance intervals as described above.

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This is a-violation (370/85-41-02).

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13. Containment Pressure Control

A review of Licensee Event _ Report (LER) 369/85-29, has indicated that the

peak containment pressure calculation for FSAR Section 6.2.1 resulted in a

value which may exceed the design internal containment pressure of 15 psig.

This analysis was performed using parameters as described in LER 369/85-29,

-specifically the WCAP-8246-Model computer code. With the procedural change

implemented on November 30, 1984, such that the order in which pump suction

transfer changed (containment spray pumps are swapped last on the 10-10

alarm), the containment spray could have been secured for a short period of

time following ice melt, this could have resulted in containment pressure

reaching 15.8 psig.

Duke has proposed that with a newer computer code, WCAP 10329 and other

considerations, containment pressure would not exceed 15 pounds, even with

the procedural changes implemented in November 1984.

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Emergency Procedures were changed on 10/4/85 to specifically require ND

spray initiation at 3000 seconds versus 3600 seconds. This reduces peak

pressure to within design pressure using the older computer code.

This item will be carried as an Unresolved Iter (369/85-40-01).

14. Inservice Testing Discrepancy

On October 18, 1985,- Quality Assurance (QA) personnel were performing QA

surveillance MC-85-63 on the Pump and Valve Inservice Testing Program

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(IWP/IWV). During the surveillance, it was discovered that valves 1NV-223

and 2NV-223, Centrifugal Charging Pump Suction from Refueling Water Storage

Tank Check Valves had never been partially stroked as required by the

IWP/IWV. These check valves are located between the Refueling Water Storage

Tank and the_ Centrifugal Charging Pu'mp Suction line. A search was conducted

for station procedures which included partially stroking these valves. None

were found. A Nonconforming Item (NCI) Report was subsequently issued by QA

to the Nuclear Production Department.

The _ IWV section of IWP/IWV provides rules and requirements for inservice

testing to verify operational readiness of certain valves. These valves are

required to perform a specific function in shutting down a reactor to cold

shutdown conditions or in mitigating the consequences of an accident.

Article 3522 of IWV states that " check valves shall be exercised to the

position required to fulfill their function unless such operation is not

practical during plant operation. If only limited operation is practical,

during plant operation the check valve shall be part-stroke exercised during

plant operation and full-stroke exercised during cold shutdowns. Valves

that cannot be exercised during plant operation shall be specifically

identified by the owner and shall be full-stroke exercised during cold

shutdowns."

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The IWV test requirement for valves 1NV-223 and 2NV-223 is to verify proper

valve movement of these valves every three months. However, in accordance

with Article 3522, the licensee has taken exception to full-stroke

exercising these valves during plant operation or cold shutdown. Instead,

.these valves were to be partially stroked during cold shutdown and fully

stroked during refueling.

Licensea personnel believe that the same reasoning for not full-stroke

exercising these valves during plant operation or cold shutdown should also

apply to the partial-stroke test. Testing of this valve requires opening

INV-221A or INV-222B, Changing Pump Suction from Refueling Wat,er Storage

Tank and Centrifugal Changing Pump Suction from Refueling Water

respectively. Failure of one of these valves in the open position aligns

the Refueling Water Storage Tank to the suction of the changing pumps with

no means of isolating the flow path. This could result in an increase in

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boron inventory in the reactor coolant system and could result in a plant

shutdown. Full-stroke exercising at cold shutdown could result in a low

temperature overpressurization. It is their intention to revise the IWP/1WV

submittal to require only full-stroke exercising during refueling. The

partial-stroke requirement will be deleted.

_. . A review of past events determined that failure to perform this type of

surveillance was an isolated incident. In addition, this discrepancy was

identified by a licensee conducted QA surveillance. Since this incident

meets the requirements of 10 CFR Part 2 Appendix C Section V.A., a notice of

< violation for failure to perform a required surveillance will not be issued.

-15. Open Items Review

Ti e following item was reviewed in order to determine the adequacy of

coarective actions, the implications as they pertain to safety of

opt rations, the applicable reporting requirements, and licensee review of

the event. Based upon the results of this review, the item is herewith

cloted.

Unit _2 LER 85-22

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