ML20198S189

From kanterella
Jump to navigation Jump to search
Insp Repts 50-445/97-20 & 50-446/97-20 on 971012-1122. Violations Noted.Major Areas Inspected:Operations, Maintenance,Engineering & Plant Support
ML20198S189
Person / Time
Site: Comanche Peak  Luminant icon.png
Issue date: 01/16/1998
From:
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:
Shared Package
ML20198S175 List:
References
50-445-97-20, 50-446-97-20, NUDOCS 9801260102
Download: ML20198S189 (20)


See also: IR 05000445/1997020

Text

, ..

r, -

EtiGLOSURE 12 '

'

U.S. NUCLEAR REGULATORY COMMISSION -

REGION IV

Docket Nos.: 60-445

50-446

License Nos.: NPF-87

NPF 89

Report No.: 50-445/97-20

50-446/97-20

Licensee: TU Electrin

- Facility
Comanche Peak Steam Electric Station, Units 1 and 2

Location: FM-56

Glen R6se, Texas-

Dates: October 12 through November 22,1997

, inspectoes: Harry A. Freeman,- Acting Senior Resident inspector

Rebecca L Nease, Resident inspector

.

Approved By: Joseph I. Tapia, Chief Branch A

Division of Reactor Projects

Attachment: Supplemental Information

.

9901260102 980116

. PDR ADOCK 05000445

9 PM _

h

. ._

__ -.

- . . - , - - . - . . . - . - _ . - - _ .- - - -.- . - . ._

~

!

>

s

,

~

EXECUTIVE SUMMnRY

-7

I Comanche Peak Steam Electric Station, Units 1 and 2

- NRC Inspection Report 50-445/97-20; 50 446/97-20

-

,

Qgrations .

'

.. Operations personnel response to the Units 1 and 2 trips was prompt, appropriate, and

characterized by excellent three-way communications and good command and control . ,

L (Sections 01.2 and 01.3).

  • Inadequate procedural guidance, complicated by a senior reactor operator's incorrect .

understanding of the system's operation, led to an inadvertent actuation of the low-;

temperature overpressure protection system during the Unit 2 cooldown.- This was a

violation of 10 CFR Part 50, Appendix B, Criterion V (Section 04.1).

- .. Woak procedural guidance, poor communications, and a lack of understanding of the

, operation of the personnel airlock doors resulted in a violation of Technical

,

Specifications related to ensuring containment integrity during core alterations -

(Section 04.2).

Operators performed core alterations prior to establishing direct communications with

'

.

- the control room when they installed lighting inside the core. This resulted in a noncited

'

.

violation of Technical Specifications (Section 04.3);

"

Maintenance

. Observed surveillances were well controlled and professional with, thorough prejob

,

briefings and excellent communications (Section M1.1).

. Poor control of work activities in the switchyard and personnel error resulted in an

automatic trip of the Unit 1 reactor from 100 percent power (Section M1.2).

. The licensee's retrieval of a damaged fuel assembly was performed in a deliberate and

l- 4 professional manner with a thorough prejob briefing. Good radiological; foreign

<

. material, and personnel safety practices were observed (Section M1.4).

__

.<- The licensee failed to repair all the structural gaps in the Unit 2 emergency core cooling

sumps that had been identified in 1994. This was a v:olation of 10 CFR Part 50,

Appendix _ B, Criterion XVI (Section M1.3). ,

"

  • . A noncited violation was identified when maintenance workers modified bushings in as --

many as 79 valve actuators without review and documentation as required by -

procedure (Section M8.1).

,

_

. - , ' --

-

~

_.. _ _

g

g

_

d

A.- e-... ,s-, .%., - - . _ , c ,,y- .v..- - - ,- .,-m- +ry . r+- +e.- .- --

e

. - . . ,. - . . -- -. -. - . .._. - - . . . . . .-

.. .

!

.; , -

.

a

-2-'-

'

,

~

t

Engineering j

..  ; The inspectors found that the licensee's evaluation of an issue concoming control room;

. pressurization surveillance testing was weak in that it failed to encompass all potential

-vulnerabilities (Section E1.1).

_

[ 1. - . Engineering provided good support to the operation of the facility by providing thorough -- -

and conservative evaluations. This support was sometimes provided after the .

- maintenance actions had already been taken (Section E2.3).

i

Plant Support

'

-*- A noncited violation of Technical Specifications was identified when a radiation  ;

protection technician failed to maintain constant physical control of a radiation area key

_ (Section R4.1).-

o

,

4

1

9

.-

t

c

_.

___

.

r

w

e -

M

ta

,l= 9 , w w-., aw a-,, um..va0 .m ,e w y n +

. . . -. -. . -

4

.

RenotLDetails

Summary of Plant Status

Unit.1

Unit 1 began the inspection period at 100 percent power, On October 27, the unit tripped due

to a generator output breaker fault which occurred during relay testing.

Unit 1 resumed power operations and, or. October 30, the unit reached full power and

remained at 100 percent power through the end of the report period.

Unit 2

- Unit 2 began the inspection period at 100 percent power. On October 24, during a downpower

in preparation for a refueling outage, the reactor was manually tripped from approximately

'10 percent power when a control rod malfunction esulted in four dropped control rods.

' The licensee commenced the third Unit 2 refueling outage on October 25. During plant

cooldown, the low-temperature overpressure protection system was inadvertently actuated.

- Unit 2 ended the inspection period in Mode 6 with the core being reloaded.

,

l. Operations

01 Conduct of Operations

01.1 General

The conduct of operations observed was characterized by good command, control, and

communications. Licensed operator responses to both the Units 1 and 2 trips were

professional and well controlled. Reduced inventory control and midloop operations

were good. However, several incidents occurred involving errors by experienced

personnel.

01.2 Unit 1 Reactor Trio

a. Insoection Scope (93702)

'At 10:44 a.m. on October 27, Unit 1 experienced an automatic trip from 100 percent

power.due to a loss of load and turbine trip. All safety systems functioned as designed.

Inspectors reported to the control room and observed the response to the event,

including operator monitoring of annunciators, supervisory control, and posttrip actions.

Operators exhibited good response to the event as exemplified by manually starting

auxiliary feedwater in anticipation of an automatic initiation. ' Following the trip, Source

Range N-31 energized as expected, but immediately failed downscale. This was the -

only material condition problem expenenced as a result of the trip.

.

.-y

1

l

-2-

b. Observations and Findinos

Operator response to the rtvent was pro 71pt and appropriate, operators used clear  !

three-way communications, and the unit supervisor and shift manager demonstrated

good command and controlin directing the event response. Tha material condition of  ;

the plant was very good and only min:,r problems were experienced as a result of the  ;

trip.

01.3 Unit 2 Downoower and Reactor.Irlp

a. Scooe (71707. 93702)

On October 24 and 25, the inspectors observed control room op+rators ramp down

reactor power n preparation for a unit shutdown for Pefueling Outage 2RFO3 using the

following procedures:

IPO-003B, " Power Operations," Revision 4

IPO-0048, " Plant Shutdown from Minimum Load to Hot Standby," Revision 2

b. Observations and Findinos

During the downpower, with Unit 2 at 56 percent power, a rod control urgent failure

alarm occurred at approximately 11:40 p.m on October 25. The licensee immediately

began troubleshooting. At approximately 12:30 a.m., the licensee resumed ramping

down power by borating while troubleshooting en the rod centrol system continued. At

4:04 a.m., with the unit at approximately 10 percent power, three control rods dropped

approximately 20 steps and another dropped to the bottom, Operaus immediately

tripped the reactor and entered the emergency operating procedures. All equipment

operated as expected and there were no emergency safety features actuations.

The downpower was well controlled and performed in accordance with procedures.

The operators used excellent three-way communications throughout the routine

downpower. Operations personnel responded to the rod drop in a deliberate manner

without hesitation. The unit supervisor demonstrated excellent command and control,

calling out the steps in the emergency operating procedure clearly and metMJically.

The operators responded well.

04 Operator Knowledge and Performance

04.1 Low-Temoerature Overoressure Protection Actuation

a. Inseection Scoce (71707)

On October 25, the licensee inadvertently actuated the low-temperature overpressure

protection system during the Unit 2 cooldown. Both pressurizer power-operated relief

valves actuated. After verifying that the pressure was below the actuation setpoint,

.

.

-3-

operators closed the block valves to secure the depressurization. The inspector

reviewed the operating procedures, the alarm response procedures, and the technical

data manual procedure used during plant cooldown.

b. Observations and Findinos

The low temperature overpressure protection system is an automatic system that

protects the reactor vessel and pip'ng systems against pressure transients during low

temperature operation. The system continuously monitors reactor coolant temperature

and pressure. System temperature is converted into an allowable pressure and then

compared to the actual reactor coolant svstem (RCS) pressure. If oressure

approaches the Clowable pressure, a antrol board annunciator will sound. If pressure

exceeds allowable pressure, another control board annunciator w;;l sound and one or

both pressurizer power-operated relief valves will open if the RCS temperature is

s350*F.

Plant cooldown was conducted in accordance with Integrated Plant Operating

Procedure IPO-005B, " Plant Cooldown from Hot Standby to Cold Shutdown," Revision

2. The inspector noted that, in several locations throughout the procedure, a statement

cautioned that RCS pressure and temperature shoulci be maintained within the limits of

Ehnical Data Manual TDM-3018, *RCS Temperature & Pressure Limits," Revision 5.

TDM-301B contained a graph showing the pressurizer power-operated relief valve Ic'n-

temperature overpressure protection setpoints. Neither the TDM nor the integrated

plant operating procedure referenced that the system armed when reactor coolant

temperature was s350'F.

During the cooldown, operators slowed the pressure reduction to maintain pressure

between 850 and 900 psig while the safety injection accumulators were being isolated

but did not slow the rate of cooldown. The procedure required that the accumulators be

isolated prior to reducing pressure below 800 psig. During this time, operators received

Alarm 2 ALB-6D,"AT LO TEMP PORV 455A APPROACHING LMT PRESS." This

annunciator alarms when pressure is within 20 psig below the reference pressure.

Operators referenced the alarm response procedure which required that they refer to

TDM 301B in order to determine the RCS pressure and temperature limits. The

procedure did not requiro that pressure be immediately reduced to clear the r' arm.

Accumulator isolation was completed and operators recommenced the prestre

reduction. At approximately 350*F, the low-temperature overpressure protection

system actuated with pressure at approximately 735 psig. The power-operated relief

valves were shut when pressure dropped below the setpoint. Following the actuation,

the operators stated that they believed that the system armed at 320*F.

10 CFR Part 50, Appendix B, Criterion V, " Instructions, Procedures, and Drawings,"

requires, in part that activities affecting quality shall be prescribed by instructions of a type

appropriate to the circumstances. ' Contrary to this requirement, Procedure IPO-005B,

Revision 2, was not appropriate to the circumstances in that the procedure did not require

that pressure be maintained below the RCS pressure and temperature limits as specified

.

.

-4-

in TDM 301B and, ar a consequence, both power-operated relief valves opened when

pressure was allowed to remain above the limit (50-446/9720-01).

In Special Report 2-SR-97-001 to the NRC Region IV Regional Administrator (licensee

letter TXX 97250, dated November 24), the liansee committed to the following:

(a) assess if the misconception of the arming temperature is a general knowledge

deficiency and conduct appropriate training if deemed necessary, (b) revise Alarm

Procedures ALM-0064A and -B to include the arming setpoint, and (c) revise Integrated

Pirnt Operating Procedures IPO-005A and -B to add appropriate provisions ;o establish

temperature and pressure cor.ditions during cooldown which will not unnecessarily

challenge low ternperature overpressure protection system actuation.

c. Conclust203

Inadequate guidance in both the integrated plant operating procedure and in the alarm

response procedure contributed to an inadvertent actuation of the low-temperature

overpressure protection system. Additionally, incorrect knowledge of system operation

by a senior reactor operator contributed to the event.

04.2 Confiauration Control of Containmem Inteority Durina Core Alteratiomi

a. Scoco W707)

In following the licensee's investigation and corrective actions conceming recent

challenges to maintaining containment integrity during core alteration, the inspectors

reviewed the following licensee documents:

Operations Notification and Evaluation Form 971384

Operutions Notification and Evaluation Form 97-1397

Plant incident Report 97-1378

Procedure SOP-9078, " Containment Personnel Airlocks," Revision 3

Procedure OPT-4088, " Refueling Containment integrity Verification,"

Revision 2.

b. Findinas and Conclusions

Loss of Containment intearity; On November 10, the licensee was performing core

alterations with both PAL doors open and de-energized. Technical Specification 3.9.4

requires, in part, that during core alterations, at least one of the two PAL doors be

capable of being closed and that each penetration providing direct access from the

containment atmosphere to the outside atmosphere shall be closed. A plant equipment

operator responsible for ensuring closure of the PAL noted that several hoses

associated with the PAL hydraulic system were disconnected to support maintenance

activities. The equipment operator questiened if this configuration would affect his

ability to close the inner door. At the tir.ie, the licensee was relying on the capability to

- _. .

.

5

i

raanually close the inner PAL door for meeting Technical Specification 3.9.4.

Operations immediately suspended fuel movement.

The PAL system engineer determined that the inner door could not be considered

r operable because its pressure equalizing valve, considered part of the PAL door, was

open. The open equalizing valve provided a direct containment atmosphere to outside

atmosphere pathway that would not ham isolated when the inner door was manually

closed. A miscommunication between oporations personnel and the system engineer

resulted in the outer door being declared operable and core alterations were resumed.

Upon r: loser inspection, the system engineer found that the pressure equalizing valve

for the outer door was also partially open, rendering the outer door inoperable. Again,

fuel movement was suspended. Operators re energized the outer door and closed its

associated pressure equalizing valve, ensured that the outer door was capable of being

closed, and then resumed core alterations. Coaducting core alterations with the PAL

doors being incqpable of being closed is a violat,on of Technical Specification 3.9.4 (50-

446/9720-02).

Procedures OPT-408B, ' Refueling Containmont Integrity Verification,' and SOP 9078,

' Containment Personnel Airtocks," were weak in that they did not provide clear

instructions concerning manual operation of the PAL doors and associated pressure

equalizing .vm The licensee revised both procedures to provide precautions and

instruction cr operating the PAL doors manually to establish containment integrity, in

addition, several other a teknssses were ;dentified. The plant equipment operator

responsible for PAL door closure was not aware that the PAL doors were de energized

and would have to be clased manua"y. The licensee determined that few operators

fully understood the operational status of the airlock and pressure equalizing valves

when the PAL doors were required to be manually operated. Core alterations were

resumed prior to verification of the operability of the outer door due to a

miscommunication between operations and the system engineer.

NeaLMtst On November 11, with core alterations in progress, the nuclear steam supply

system work wintaow manager recognized a potential containment integrity breach when he

discovered that the hand hole covers in SG 2 04 had been removed. Another concurrently

scheduled work activity, to remove and replace a feedwater instrument isolation valve,

would have completed an open pathway through the hand holes, Steam Generator 2 04,

and the feedwater instrument isolation line to the outside atmosphere. Upon discovery, the

licensee immediately suspended core off load and initiated an investigation which verified

that the valve had been welded in placa prior to the time when tb i hand hole covers had

been removed during core alterations. Technical Specification 3.9.4 had not been violated.

The inspectrls reviewed this near miss and found that, during the outage, the licensee

relied on sequencing work to ensure containment integrity during core alterations.

Specifically, when work on containment penetrations inside containment had been

completed. fuse penetrations were closed, and work packages were issued to allow

work on reratrations outside containment. Eddy current work in Steam Generator 2-04

had been cornpleted and the steam generator hand hole covers were ins'alled.

._ - = . - _- - _ _ - ___ __- - _

.

6-

However, since the work package was not closed and the clearance was still in effect, a

technician removed the hand hole covers for some followup eddy current investigation.

Operations personnel did not authorize the hand hole cover removal and were unaware  !

that the containment boundary had been opened. During this time frame, the work

order for removing and replacing the feedwater instrument isolation valve had been i

authorized. Had both jobs been conducted at the same time, an air to-air breach of  !

containment would have occurred during core alterations and would have been a I

violation of Technical Specification 3.9.4. The inspectors concluded that controls for

maintaining containment integrity were weak and, in this case, would not have

prevented a breach in containment integrity during core alterations.

The licensee implemented the following intermediate corrective actions to prevent

recurrence during fuel reload: (1) no work was permitted on containmeat boundary

equipment during core alterations and all open work order packages wee retrieved;

(2) the NSSS work window manager was assigned the primary responsibility for

containment integnty; and (3) workers were not permitted to sign back on a clearance

until the work order had been re reviewed by operations.

c. CQDclusions

The inspectors concluded that the licensee's controls for ensuring containment integrity

during core alterations were weak. Weak procedures for operating the PAL doors

resulted in the failure to meet the Technical Specification requirement of being capable

of closing the PAL door during core alterations. Contributing factors to this included

poor communications and operator knowledge deficiencies. Finally, relying on the

sequencing of work activities in the outage schedule would not have prevented work

activities from occurring concurrently and could have resulted in a breach of

containment integnty during core alterations.

O4.3 Core Alterations Without Communications

a. lDipection Scopp (71707)

On November 8, the licensee inserted on underwater light into the reactor vessel in

preparation for fuel off-load prior to establishing direct communications between the

control room and the refueling station. The inspector reviewed the cause of the event

and the licensee's immediate and planned corrective actions.

b. Obietyations and Findin95

Technical Specifications define core alterations as the movement or manipulation of

any component within the reactor pressure vessel with the vessel head removed and

fuelin the vessel. Technical Specification 3.9.5 requires that direct communications be

maintained boNveen the control room and personnel at the refueling station during core

alterations. Contrary to these requirements, the licensee placed an underwater light

- _

-- _. ._ _ . .- . _ _ - - _ - - - - . -_ _ - _ . - _ _ _ . _ -

.

'

,

-

7

,

ir. side the reactor ve:,sel prior to establishing direct communications between the i

control room and the refueling station.

After the light had been placed into the vessel, the fuel handling supervisor was alerted

to the fact that this constituted a core alteration. The fuel handling supervisor halted

,

further fuel handling activities. As part of their corrective actions, the licensee issued a

lessons learned report on the event, established signs on the refueling bridge to remind

personnel of what constrtuted a core alteration, and conducted refresher training to all

' fuel handling supervisors and contractor personnelinvolved with the refueling. The

licensee issued a ONE form which will be dispositioned as a plant incident report.

Placing an underwater light into the reactor vessel above the fuel had negligible effect on

core reactivity, in the improved standard h chnical Specifications, not yet approved for

the licensee, cote alter: tion has been redefined to be the inovement of any fuel, sources,

or reactivity control components within the reactor vessel with the vessel , sad removed

and fuelin the vessel. The inspector concluded that the event had little actual significance

and that the licensee's corrective actions were apprepriate. This nonrepetitive,

licensee identified, and corrected violation is being treated as a noncited violation,

consistent with Ssction Vll.B.1 of the NRC Enforcement Policy (50-446/9720-03),

c. Conclusions

A noncited violation of Technical Specifications was identified related to performing

core alterations prior to establishing direct communications with the control rocM when

operators installed lighting inside the core.

08 Miscellaneous Operations issues (92901)

08.1 (Closed) Violation 50 445f4461/9706-01: f ailure to establish procedures to ensure

that alllicensed operators that have their licenses conditioned to wear corrective

lensos for the eye, always have available appropriate lenses qualified for a self-

contained breathing apparatus, in the enclosed Notice to NRC Inspection Report 50

445(446)!97-06, the NRC concluded that the information regarding the reason for the

violation and the corrective actions taken and planned were already adequately

addressed on the docket and that a response was not necessary unless the licensee

concluded that the descriptions or corrective actions did not accurately reflect their

position. The licensee did not respond and this item is closed.

- , . - . -- - . . - - .

- -- - - - ,

-

F

.

8-

lL Maintenance

M1 Conduct of Maintsnance

M1.1 General Comments

in general, maintenance and surveillance activities were characterized by

knowledgeable individuals and professional performance. Although the planning and

preparation prior to the start of the Unit 2 outage was thorough, numerous problems

occurred during the outage. This included damaged equipment, work stoppages, and

personnelinjury Several of these issues involved mistakes by experienced personnel.

a. Inanection Scone (61728. 82707)

The inspectors observed all or portions of the following work activities:

Turbine-driven Auxiliary Feedwater Pump design modifications

Diesel Generator 2-01 maintenance

OPT 214A, * Diesel Generator Operability Test,' Revision 10

OPT-467A, "Trair, A Safeguards Slave Relay K609 Actuation Test," Revision 3

b. Observations and Findinas

The inspectors found the work performed under the above activities to be well

controlled and professional. Prework briefings were timely and thorough. Excellent

three-way communications were observed throughout the performance of the work.

Individual work groups reviewed the work steps and discussed the potential

,

consequences and appropriate responses. Operators performing the work read the

'

steps aloud before performing them.

- M1.2 Unit 1 Reactor Trio Review

a. Scope

in followup to the October 27 reactor trip, the inspectors reviewed the licensee's

immediate and interim actions for controlling work activities in the switchyard. - The

inspectors also reviewed the Interface Responsibilities Memorandum, dated July 2,

1997, which described the licensee's process for controlling work in the switchyard.

b. Observations and Findinas

On October U, Unit i experienced an automatic trip from 100 percent power due to a

loss of load and turbine trip (Section 01.2) Unit 2 was in a refueling outage, and the

Unit 1 generator was supplying the grid through fireaker 8010 to the west bus of the

345kV switchyard; The east bus of the 345kV sv'itchyard was isolated to support

lightning protection modifications. At the time of the trip, Glen Rose Transmission

r =

' " J.,5., -

_ _ - - _ . - - . . . - _ _ .

.

.

.c.

protection and control technicians were testing Breaker 8000 on the east bus of the

345kV switchyard. Glen Rose Transmission is a separate division within the TU

Electric Company. In preparation for testing, technicians had closed Breaker 8h 0 and

opened the two air switches on either side. When Breaker 8000 received the test trip

signal to open, an unexpected pole disagreement delayed the opening enough to allow

the protecjve lockout function timer to start and time out. This resulted in a protective

lockout relay actuation which opened Breaker 8010, causing a loss of load and

subsequent Unit 1 turbine and reactor trips. All work in the switchyard was immediately

- suspended and was permitted to resume only after licensee management was fully

briefed on the scope and potentialimpact. The licensee determined that the cause of

the trip was failure of Glen Rose Transmission technicians to defeat the protective

lockout feature on Breaker 8000.

.The inspectors reviewed the licensee's process for controlling work in the switchyard

and found it to be a nbiguous and lacking formality. The Interface Responsibilities

Memorandum, dated July 2,1997, provided little guidance concerning review, approval,

or coordination of switchyard work. The interface agreement did not require switchyard

work to be reviewed by Comanche Peak personnel. Switchyard work was controlled

through the work control scheduling process. Typically, only work thought to have a

potential for impacting plant operation was shown on the schedule and not all

cwitchyard work was scheduled.

The licensee's investigation revealed several weaknesses associated with control of

work in the switchyard. Since few Glen Rose Transmission technicians had site

access, the technicians actually performing the work were not necessarily those that

attended the prejob briefing. Contrary to the Interface Responsibilities Memorandum, a

single point of contact between Operations and Glen Rose Transmission had not been

designated. Switchyard breaker testing was performed without procedures, relying on

skill of the craft and electrical diagrams. Only that work which was scheduled received

Comanche Peak review for impact to the plant. The testing of Breaker 8000 was not

scheduled and as a result did not receive Comanche Peak review for impact to the

plant.

The licensee has established a task team to develop long term corrective actions. In

the interim, all switchyard work is described on a written plan, reviewed by Comanche

Peak management, and briefed by Glen Rose Transmission technicians.

c. Conclusions

The inspectors concluded that the trip was caused by personnel error because Glen

Rose Transmission protection and control technicians did not fully understand or review

the impact that the breaker testing on the east bus could have on the west bus. In

addition, the licensee lacked a formal process for effectively controlling activities in the

switchyard.

. ., . _. ._ -- -

__.

.

10-

W 3 fppQpQu f Corrective Actions on Containment Sumps

section Scooe (62707. 92902)

On November 8, the licensee identified 16 gaps in the emergency core cooling system l

,

structural support members that were larger than the fine mesh openings. Following

completion of the repairs to the Unit 2 sumps, the inspectors visually confirmed that the

gaps identified by engineering had been repaired. The inspectors reviewed t%e work

orders originally used to repair the gaps in 1994.

b. Observations and Findinas

in 1994. Violation 50-445(446)/9423-03 was issued which stated that the licensee's

design control measures did not adequately verify that the Units 1 and 2 containment

sump trash racks met design requirements. Structural gaps in each of the emergency

core cooling system containment sumps were larger than the fine mesh openings and

did not meet design basis requirements. The licensee repaired the Unit 2 gaps under

Work Orders 194 078046-00 and 194 078047-00. On November 8,1997, the

licensee identified nine gaps in the Train A sump and seven gaps in the Train B sump

which did not meet the design basis requirements. The gaps were approximately

0.625 inches long and the two widest were between 0.250 inches and 0.375 inches

wide. Of these 16 gaps,8 had been previously identified in 1994, but had not been  ;

!

adequately corrected. When the sump gao issue was originally identified in 1994, the

licensee contracted with Westinghouse to perform an engineering evaluation to  :

consider what affect the ingestion of debris into the containment sumps could have on

containment spray and emergency core cooling. That evaluation concluded that the

gaps did not affect the operability of these safety systems. The inspector verified that .

'

the recently identified gaps were bounded by the 1994 evaluation and that the

operability of the systems was again not affected.

The inspector reviewed the work orders used in 1994 to repair the Unit 2 sump

structures. Neither work order specified the locations of the gaps to be repaired.

Instead, the work orders directed the work group to use stainless steel plates to cover

openings and reduce the gaps to no more than 0.115 inches. The work orders required

that a quality control inspector inspect the structure for holes or gaps, which exceeded

the criteria specified in the design change. The design change directed that any hole or

gap with a side dimension or diameter greater than 0.115 inches that would allow

debris to flow into the sump be repaired. The quality control inspecticas had been

documented as being satisfactory.

FSAR Section 6.2.2.2.7 stated that the fine screen had a 0.115 inch opening to ensure

that the spray nozzle orifices and grid assemblies in the reactor core do not clog and

that trash racks and screens are provided to preclude clogging of the recirculation lines

and any of the system's components. The section stated that the design of the

containment spray recirculation sumps satisfied the requirements of NRC Regulatory

Guide 1.82, " Sumps for Emergency Core Cooling and Containment Spray Systems,"

. l

4

11-

I

dated June 1974. Regulatory Guide 1.82 states that the size of the openings in the

fine screen should be based on the minimum restrictions found in systems served by l

'

the sump.

The original ONE form which documented the deficiencies in 1994 did not specify the j

locations of gaps but instead stated that there were approximately 48 gans in the Unit 2  !

sumps. The ONE form wording was not clear as to whether there were 48 gaps in l

each sump or 48 gaps total. Weld data record sheets in the work orders indicated that

71 repairs were made in the Train A sump and that 81 repairs were made in the Train B

sump.

10 CFR Part 50, Appendix B, Criterion XVI, ' Corrective Actions,' requires, in part, that

conditions adverse to quality and nonconformances be promptly identified and

corrected. Contrary to this requirement,16 gaps greater than the maximum allowable

gap were not promptly identified and corrected. On November 8,1997, eight previously

identified and eight addit!onal structural gaps, that exceeded the Final Safety Analysis

Report description of 0.115 inches, were identified in the Unit 2 emergency core cooling

sumps. This is a violation (50-446/9720-04).

c. Conclusions

The licensee fJiled to promptly identify and correct the gaps in the Unit 2 emergency

core cooling system containment sumps. The original work orders were poorly written

because they did not specify the locations of the gaps to be repaired but instead relied

on the work groups to locate and repair the gaps. Several gaps which did not meet the

design basis requirements had been identified in 1994.

M1.4 New Fuel Assembiv Damage

a. lnspection SconeJ62707. 93702)

The inspector responded to the site in response to a fuel handling event in order to

verify that the fuel assembly was in a safe condition and did not represent a potential

radiological hazard to stored spent fuel. The inspector reviewed the cause of the

damage, the licensee's actions to secure the damaged assembly, and the actions

taken to prevent future damage.

b. QbicIyations and Findin95

While lowering a new fuel assembly into the high density storage racks in Spent Fuel

Pool X-02 in high speed, the fuel handler observed a sudden decrease in load cell

reading concurrent with unexpected movement of the long handled tool attached to the

assembly. The operator immediately raised the assembly. The operator and fuel

handling senior reactor operator observed that the assembly appeared to be damaged.

All fuel movement was secured while the licensee conducted an investigation. The

. _ _ , - . . _. -_ __ _ _ . . _ . - --

.

I

-

12

licensee suspended placing any more assemblies into the high-density fuel racks until

procedural, personnel, and/or equipment weaknesses could be resolved.

Ths inspector verified that the damaged fuel assembly did not represent a hazard to

any spent fuel assembly. The inspector noted that the licensee had stationed a

refueling senior reactor operator in the spent fuel pool area to monitor any potential

changes to the assembly since it was being held by the long-handled tool and to

prevent any unauthorized individual from approaching the refueling bridge. Because

the fuel assembly was being held by only 4 of the 25 guide tubes, the licensee secured

the assembly to the hoist by using two loops of aircraft cable slung around the lower

nozzle. The licensee believed that any lateral movement through the pool could

damage the remaining guide tubes, so a temporery design change was implemented to

allow the use of the cable prior to removing the assembly from the pool.

The fuel assembly was damaged when an edge of the lower nozzle contacted the edge

of the fuel rack during lowering. As the weight of the assembly shifted from the long-

handled tool to the fuel rack, the fuel assembly began to lean. A postevent review by

the fuel vendor concluded that a 3 degree lean angle could damage the fuel assembly.

The vendor also stated that moving the fuel would not be advisable unless seven or

eight of the guide tubes remained intact.

The fuel handler was required by procedure to lower the fuel assembly into the high

density racks in slow speed until 10 inches had been inserted into the rack. The

assembly could then be lowered in high speed. The fuel handler had one hand on the

pendent controlling the hoist and the other hand on the long-handled tool to help guide

the assembly into the rack. The handler was required to monitor a load celllocated on

the hoist, guide the assembly into the rack, observe when 10 inches had been inserted,

and then shift to fast speed in a smooth motion. Although the fuel handler was a

contractor that had a significant amount of experience in fuel movement, he failed to

correctly perform this evolution because he did not wait until the assembly was inserted

at least 10 inches into the rack before lowering it in high speed.

The licensee's prejob briefing for the retrieval of the damaged fuel assembly was

thorough and appropriately focused on personnel, radiological, and equipment safety.

Self checking and verification techniques were stressed. Access to the refueling area

was tightly controlled to avoid confusion. Throughout the evolution, the licensee

demonstrated proper radiological safety and foreign material exclusion practices. The

inspectors concluded that all aspects of this difficult evolution were well controlled and

perforrned in a deliberate and professional manner.

c. Conclusions

The inspector concluded that the damaged fuel assembly was damaged due to

operator error. The inspector concluded that the damaged fuel assembly was carefully

controlled and moved and that the licensee's plans to suspend further use of the high-

density fuel racks until the issue could be resolved was appropriate.

4

i

1

,

13-

l

M8 Miscellaneous Maintenance issues (92902)

M8.1 (Closed) Unresolved item 50-445(446)/9717-03: modifications made to Fisher-Type

667 air-operated valve actuator bushings without the required review. As previously

desenbed in NRC Inspection Report 50-445(446)/9717, this unresolved item was

opened for the inspectors to: (1) evaluate the extent and impact of modifications to the

actuator bushings, (2) determine if the appropriate postmaintenance tests were

performed on the affected steam generator atmospheric relief valves (ARVs), (3) verify

that the licensee corrected the Master Equipment List, and (4) evaluate any generic

aspects of the issue.

The licensee completed its investigation and did not identify any additional

modifications to actuator bushings, bringing the maximum number of unreviewed

modifications to 70, most of which were not safety related. The licensee concluded that

the modifications were acceptable because the small holes drilled in the actuator

bushings did not affect their functionalintegrity. The inspectors agreed with this

evaluation. The licensee also determined that the steam generator ARVs had been

postmaintenance tested after the elastomers were replaced. The inspectors reviewed

the Master Equipment List entries for the ARVs and found that they had been

corrected. After conducting interviews with maintenance personnel and management

and after reviewing the licensee's investigation report, the inspectors did not identify

any generic concem related to the issue.

Technical Specification 6.8.1 requires, in part, that the licensee establish, implement,

and maintain procedures covering the activities referenced in Appendix A of Regulatory

Guide 1.33, Revision 2, February 1978. Appendix A, Secticn 9, requires procedures for

performing maintenance. Licensee Procedure STA 206, " Review of Vendor

Documents and Vendor Technical Manuals," Revision 19, stated that vendor

documents or correspondence that will be used for design, testing, or other input for

CPSES activities shall receive review and approval on a vendor document review

traveler or be incorporated into an applicable vendor technical manual prior to final

acceptance and approval of the activity, inspectors concluded that the licensee

violated Technical Specification 6.8.1 in that maintenance personnel failed to follow

procedure when they modified as many as 79 Fisher-Type 667 valve actuator bushings

(some of which were associated with safety related valves) without proper

documentation or review. This nonrepetitive, licensee-identified, and corrected

violation is being treated as a noncited violation consistent with Section Vil.B.1 of the

NRC Enforcement Policy (50-445(446)/9720-05).

_ _ _ _ _ _ _ _

.

.

14

I

Ill. Engineerlag

E1 Conduct of Engineering

E1.1 Control Room Pressurization Unit Surveillance Plant incident Evaluation l

a. Insoection Scooe (37551)

The inspector reviewed Plant incident Evaluation 97 934 which addressed control room

pressurization unit surveillance test acceptance criteria inconsistencies. The evaluation

was initiated following questions raised by the inspector as documented in NRC

Inspection Reports 50-445(446)/9717 and 50-445(446)/9718. The inspector reviewed

the evaluation to assess the thoroughness and quality of the self assessment.

b. Observations and Findincs

The inspector found that the evaluation did not include any type of formal charter

documenting the purpose or scope of the evaluation. Consequently, the inspector was

unable to assess whether the evaluation fully met the licensee's expectation that all of

the issues that should have been addressed be resolved. Nevertheless, the evaluation

thoroughly reviewed the issue of leaving the as-left values of pressurization flow above

the design basis value.

The inspector reviewed the data provided in the evaluation and noted that there

appeared to be a correlation between the measured flow rates and the dates that the

test was performed. Tests conducted during the surnmer months were generally

measured at higher flow than tests conducted during the winter. Additionally, the l

inspector noted that the licensee was committed to ANSI /ASME N510-1980, " Testing of

Nuclear Air Cleaning Systems," which stated that the number of readings taken to

determine flow through the duct should not be less than 16, The inspector noted that

the procedure only required 12 readings. The licensee issued another ONE form to

address both the adequacy of the evaluation and why only 12 readings were required.

c. ConclusioD1

The inspector concluded that, while the evaluation was conducted by qualified

personnel who thoroughly reviewed the specific issue of exceeding the design basis, it

did not encompass all potential weaknesses in testing the pressurization units. The

licensee initiated additional ONE forms to address the additional questions raised by

- the inspector.

. .- - .__ - .

.

?

15-

E2 Engineering Support of Facilities and Equipment

.

E2.1 Qual Train comoonent Coolina Water System Outmoe

a. Insoection Scoon (37551) ,

,

The inspector reviewed 10 CFR 50.59 Evaluation SE 97-81 which concerned a dual

train component cooling water system outage cjuring the Unit 2 refueling outage

following the reactor core offload.

3

b. Obsgyations and Findinas

Prior to the Unit 2 refueling outage, the inspector questioned the nuclear steam supply

system work window manager regarding the safety evaluation prepared for conducting a

dual train outage. The work window manager was not aware of any evaluation. Within the

next few days, the licensee informed the inspector that D. C. Cook had made a 10 CFR

50.72(b) notification for being outside design basis for conducting a dual train component

cooling water system outage. The licensee informed the inspector that they had pulled

their planned dual train outage out of the schedule until they had a chance to complete

their safety evaluation. ,

The inspector reviewed the licensee's safety evaluation. The licensee concluded that

the planned dual train component cooling water system outage with the reactor core

fully offloaded did not represent an unreviewed safety question. The inspector found

that the licensee's evaluation was thorough and technically correct.

c

E8 Miscellaneous Engineering issues (92902)

EB1 (Closed) Insoection Followuo item 50-445(446)/9718-02: seismic qualification of

integrated leak rate test rig. This item was left open to review the licensee's evaluation

of the connection. In ONE Form 97-1103, the licensee concluded that, during a design

basis earthquake, the rig could potentially have an undesirable interaction with one

source range nuclear instrument cable. Although the licensee concluded that a

i

damaged source range nuclear instrument cable would not have prevented the safe

shutdown of the reactor, the licensee determined that the connection should be

.

modified to assure conservatism for future operations. The inspector concluded that

the licensee's evaluation was thorough and that the proposed modification was

conservative.

l_V. Plant Sunnort -

R1 Radiological Protection and Chemistry Controls

The inspectors observed good radiological practices being implemented by all plant

personnel. Workers were familiar with their radiological work permit requirements. On

>

,_

.. _ . _ _

.

.

16

one occasion, the inspectors observed a crane operator swinging potentially

contaminated reactor vessel studs outside of the controlled area boundary to avoid

hazards to personnel inside the area. After the inspector pointed out that the studs

had to be surveyed p*. t to passing outside of the boundary, the crane operator

ensured that the studs remained inside the boundary during the movement.

R4 Staff Knowledge and Performance

R4.1 Locked Hiah Radiation Area Key Control

a. laspection Scooe (71750)

On November 8, the licensee discovered that positive control of a locked high radiation

area key had not been maintained. After contacting the individual who signed for the

key, the licensee located the key in a bag at the steam generator platform. The

inspector reviewed the circumstances and corrective actions surrounding the control of

the locked high radiation area key.

b. QbigIYatipas and Findinas

Technical Specification 6.12.2, *High Radiation Area," requires, in part, that areas

accessible to individuals with radiation levels greater than 1000 mrem /h at 30 cm shall

be provided with locked doors to prevent unauthorized entry and that the keys shall be

maintained under the administrative control of the shift manager on duty and/or

radiation protection supervision.

Radiation Protection Instruction RPI 110, * Radiation Protection Shift Activities,'

Revision 6, provided administrative instructions on the control of keys to locked high

radiation areas. Section 6.5.1.4 required that radiation area keys only be issued to the

security shift lieutenar't, the shift manager, or a radiation protection quahfied individual.

Section 6.5.1.3 required that the individual, to whom the key is issued, maintain

constant physical possession of the key.

Contrary to the requirements of RPI 110, a radiation protection technician to whom the

key was issued failed to maintain constant physical possession of the key when the key

was given to a contractor to unlock a cover on a steam generator manway. When the

oncoming crew conducted a key inventory, they discovered that the key was missing.

When contacted, the technician to whom the key was issued informed the lead

technician that he had directed that the key be left in a bag on the steam generator

platform, where it was subsequently found.

The inspector found that the area where the key was located was controlled by

radiation protection and that the key was not used by an indnndual to gain unauthorized

access to a locked high-radiation area. As a corrective measure, the radiation

protection manager reiterated the requirements of the procedure and his expectations

- __ _

.

.

17

that the procedures be followed. Training was conducted with all radiation protection -

personnel.

c. Conclusl0D1

Failure of the radiation protection technician to maintain constant physical control of the

radiation area key was a violation of Technical Specification 6.12.2. This nonrepetitive,

licensee-identified, and corrected violation is being treated as a noncited violation

consistent with Section Vll.B.1 of the NRC Enforcement Policy (50 445(446)/9720-M).

81- Co :due* of Security and Safeguards Activities

Throughout the inspection period, the inspectors observed alert security officers

appropriately manning their assigned posts. On one moming, the inspectors noted that

fog had significantly reduced visibility. The inspectors verified that security had

appropriately responded as required by the security plan.

V. Management Meetinas

X1 Exit Meeting Summary

The inspectors presented the results of the inspection to members of licensee manaqement at

the conclusion of the inspection on November 25. The licensee stated that they had not yet

completed their investigation into the emergency core cooling system sump gap issue. The

inspectors asked the licensee whether any materials examined during the inspection should be

considered proprietary No proprietary information was identified.

..

-.. -- . .. . - . . - . -. ..

.

!

  • ;

ATTACHMENT  ;

SUPPLEMENTAL INFORMATION ,

PARTIAL LIST OF PER?.ONS CONTACTED

l

Licensee

M. R. Blevins, Plant Manager

J. R. Curtis, Radiation Protection Manager

D. L. Davis, Nuclear Overview Manager .

J. J. Kelley, Vice President, Nuclear Engineering and Support

M. L. Lucas, Maintenance Manager .

D. R. Moore, Operations Manager

C. L. Terry, Group Vice President, Nuclear Production

.

INSPECTION PROCEDURES USED

37551 Onsite Engineering

61726 Surveillance Observations

'

62707 Maintenance Observations t

71707 Plant Operations

71750 Plant Support Activities

92901 Followup' Plant Operations

92902 Followup Maintenance

92903 Followup Engineering

93702 Prompt Onsite Response To Events At Operating Power Reactors

P

ITEMS OPENED AND CLOSED

Opened

50-446/9720-01 VIO Inadequate procedure resulted in both power-operated

relief valves opening who pressure was allowed to

remain above the low-temrature overpressure

protection system limit- Mtion 04.1).

50-446/9720 02 VIO Conducting core alterations with the personnel airlock

doors incapable of being closed (Section 04.2).

.. - . . . .. . . . . . . - .

_ - _ . _ _ _ _ _ _ _ __ . _ _ _ _ . _ _._ __._ .

,

'

.

2

50-446/9720-03 NCV Failure to establish communications prior to placing an

underwater light in the reactor vessel (Section 04.3).

50-446/9720-04 VIO Failure to promptly identify and correct

16 nonconformances in the ECCS sumps including eight

previously identified structural gaps (Section M1.3).

50-445(446)/9720-05 NCV Failure to follow procedure when mod,fying Fisher Type

667 valve actuator bushings without proper

documentation or review (Section M8.1).

50-446/9720-06 NCV Failure of the radiation protection technician to maintain

constant physical control of the radiation area key was a

violation (Section R4.1).

Closed

-50-446/9720-03 NCV Failure to establish communications prior to placing an

underwater light in the reactor vessel (Section 04.3).

50-445(446)/9720-05 NCV Failure to follow procedure when modifying Fisher Type

667 valve actuator bushings withost proper

' documentation or review (Section M8.1).

50-446/9720-06 NCV Failure of the radiation protection technician to maintain

constant physical control of the radiation area key was a

violation (Section R4.1).

50 445(446)/9706 01 VIO Failure to establish procedures to ensure that alllicensed

operators that have their licenses conditioned to wear

corrective lenses for the eye, always have available

appropriate lenses qualified for a self-contained breathing

apparatus (Section 08.1).

50-445(446)/9717 03 URI Review scope of accumulator bushing modification and

generic aspects of maintenance modifications

(Section M8.1).

c

'

,

50-445(446)/9718-02 IFl Review of seismic qualification of integrated leak rate test

rig (Section E2.1).

-