ML20148H850

Insp Repts 50-010/97-06,50-237/97-06 & 50-249/97-06 on 970308-0418.Violations Noted.Major Areas Inspected: Operations,Maint,Engineering & Plant Support

ML20148H850
Person / Time
Site:	Dresden
Issue date:	06/01/1997
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20148H837	List: ML20148H833 ML20148H839 ML20148H850
References
50-010-97-06, 50-10-97-6, 50-237-97-06, 50-237-97-6, 50-249-97-06, 50-249-97-6, NUDOCS 9706110308
Download: ML20148H850 (22)

See also: IR 05000010/1997006

Text

m _ _ . . . _ _ - _ . _ . _ _ _ _ _ . _ ._. _ .. ._

j. - -

, t

..

l

l

,

,

.

i

i

U.S. NUCLEAR REGULATORY COMMISSION

j

l REGION lil ,

!I

,

t

. Docket Nos

50-10; 50-237; 50-249 l

f

!

License Nos: DPR-2; DPR-19; DPR 25 ,

l

l

Report No: 50-010/97006; 50-237/97006; 50-249/97006

4

I

1

Licensee: Commonwealth Edison Company 1

Facility: Dresden Nuclear Station Units 1,2' and 3

l Location: Dresden Nuclear Power Station

Commonwealth Edison Company

6500 North Dresden Road

Morris, IL 60450

!

I- Dates: March 8 through April 18,1997

Inspectors: D. Roth, Resident inspector

C. Brown, Resident inspector, Big Rock Point  !

J. Hansen, Resident inspector, LaSalle -

C. Settles, inspector, Illinois Department of Nuclear Safety

L

Approved By: W. L. Kropp, Chief

Reactor Projects Branch 1

!' l

l

.

I

i

,

)

9706110308 970601

- PDR ADOCK 05000010 ,f  ;

G _ .PDR L,.

,

'

__ _ , .._

_ _ __ , _ _ - ~--

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

I ,

. . j

.

EXECUTIVE SUMMARY

Dresden Nuclear Staton Units 1,2 and 3

NRC Inspection Report 50-10/970')6; 50-237/97006; 50-249/97006

i

l This inspection included aspects of licensee operations, maintenance, engineering, and

l

plant support. The report covers a 6-week inspection period.

!

Operations

For those activities observed, the inspectors concluded that the operating crews performed

major evolutions, such as the two unit shutdowns, in a controlled manner. The crews

l were observed to anticipate the plant responses to various evolutions and tests.

The operating crews on shift for two shutdowns were not aware of an issue pertaining to

the method of inerting and de-inerting the containment that was identified at another

licensee's facility (LaSaile). . During each shutdown, the inspectors identified to the

! operators the potential to bypass the suppression pool during an accident.

Maintenance

!

! Cont ol room operators were not aware of work started on the high pressure coolant

injection (HPCI) pump turbine lagging and scaffolding while the HPCI pump was in the

standby mode.

,

With the exception of the problems noted with jobs discussed in the report, the

. maintenance work observed by inspectors was performed correctly. No instances of .  ;

,

incorrect work were seen. The workers had the necessary procedures and 'were following 1

them. No inadequacies were noted in the procedures.

l  !

! Although the troubleshooting of the high/ low voltage condition on the 24/48 Vdc battery j

!. charger was good, the placement of a voltmeter across the battery to monitor voltage was  !

i

not treated as a temporary system alteration or authorized by an approved process. This l

l

was a violation. Also, the control room operators were unaware of the installation of the  ;

voltmeter.

Engineering

The inspectors concluded that the licensee did not take timely action to address an issue

,

identified at the LaSalle station. A method in use to de-inert the containment bypassed

the torus safety function. During two shutdowns, the inspectors had to inform the

l

7

operating crews that the issue was a concern at Dresden. This resulted in the operating

'

crew changing the de-inerting during the shutdown after being informed by the inspectors.

i

The licensee did not communicate the de-inerting issue well between the various

l departments. Although regulatory assurance and engineering were aware, these

departments did not keep the operating crews informed. Additionally, representatives of

l-

,

I.

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

_ _ _ _ . _ _ _ _ _ _ _ . _ _ _ _ _ . _

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

,

.

, . .

!

i

j

-

1

i

l operations were aware of the issue from the corporate call, but did not assure resolution of

l the concern.

l

j'

The inspectors identified weak performance by the system engineer in directing the

performance of the engineering surveillance to set the governor compensation on the

Unit 3 emergency diesel generator. The inspectors also noted that the procedure that was

. being used was inadequate. However, the nonlicensed operator who was operating the

j EDG demonstrated excellent attention-to-detail and a questioning attitude and prevented a

i trip of the EDG.

Plant Suocort

i

! The inspectors noted that the radiation protection " greeter" program continues to be used

j to enforce plant rules and appears to be effective. Station security personnel assigned to

monitor the auxiliary electric equipment room fire and security doors and to act as fire

j watches were knowledgeable of their duties.

3

i

. .

-l

9

l

REPORT DETAILS j

l

Summary of Plant Status

Unit 2 entered the period at full power. Full power was maintained, except for brief load

decreases for surveillance tests and maintenance inspections, until April.10. On April 10,

a ahutdown was begun in response to inoperable electrical breakers. The breakers

provided power to the containment cooling service water (CCSW) system and were the

normal supplies to the emergency buses. The forced outage (D2F27) continued through

the end of the inspection period.

Unit 3 entered the period at full coastdown power. The licensee started shutting down on

March 28 and manually inserted all control rods at 2:29 a.m., March 29th, starting the

- 14th Unit 3 refueling outage (D3R14). The outage was scheduled to last about 69 days.

1. Operations

01 Conduct of Operations

01.1 General Comments (71707)

I

The inspectors conducted frequent reviews of ongoing plant operations. Overall,

the conduct of operations was safe and in accordance with procedures.

During the inspection period, several events occurred, some that required prompt . i

notification of the NRC per 10 CFR 50.72 or Licensee Event Reports (LERs) per l

10 CFR 50.73. Some of the events are listed below- 1

i

March 2 Technical specification (TS) verifications required while Unit 3

emergency diesel generator (EDG) was inoperable were not

performed. l

March 29 Unit 3 unexpected Group V isolation while removing isolation

condenser system from service.

April 11 Unit 2 containment cooling service water (CCSW) and bus-tie to the

EDG-supplied bus considered inoperable due to Merlin-Gerin 4kV-

breakers being declared inoperable (open/close limit switch assembly

susceptible to cracking). Unit 2 shut down due to TS requirements.

April 16 Unit 2 welds on containment penetration supporting "B" low pressure

coolant injection (LPCI) found outside of Updated Final Safety

Analysis Report (UFSAR) allowable stress limits resulting in LPCI

system inoperability.

4

._ . . _

_ _ . _ . _ . _ _ _ . _ . . . . _ . _ _ . _ . _ . _ _ . . _ _ _ . _ _ . . _ . _ _ _ . . _ _ . _ _

,

, . .

!

-

.

5- Preliminary assessment of the licensee's responses to these events determined the

'

responses to be adequate. Final review of some of these events was documented

t in this report. Final review of others will be done after receipt of the associated

"

LERs.

l

l: 03 Operations Procedures and Documentation

O3.1 Onerations Procedure Review (71707)

'-

~ The inspectors reviewed select procedures and compared them to the requirements

'

in the UFSAR. Dresden Safe Shutdown Procedure (DSSP) 0100-CR Rev.10, " Hot

i Shutdown Procedure - Control Room Evacuation" was reviewed and compared to

!. UFSAR Section 7.4, " Safe Shutdown." No discrepancies were identified.

,

) 04 Operator Knowledge and Performance

1

j 04.1 Operator Performance

i

a. ~ Insoection Scone (71707)

The inspectors assessed routine control room operations by performing sustained

control room observations, monitoring shift turnover, review of logs, and

i discussions with the operations staff. The inspectors also observed the Unit 3

i reactor shutdown for refueling, and the Unit 2 forced shutdown for issues related

l . to 4-kV breakers.

Procedures and diagrams reviewed included: Print M-356, Diagram of Pressure

i Suppression Piping, Revision BE; DGP 2-1, Reactor Shutdown, Revision 38; Unit 3

Shutdown Plan (D3R14 March 1997), Revision 0; and the Dresden Emergency

l Operating Procedures (DEOPs).

s

! b. Observations and Findinos

i

Routine Operations

i

The inspectors observed that the operators were attentive to the panels,

knowledgeable of the reasons for lit annunciators, and aware of activities in the

plant. The inspectors observed that the control room demeanor was maintained

e professionally. For example, the operators were observed to verify that each

j person had legitimate business near the panels if the control room appeared to be )

.

crowded.

. Radwaste Control Room Operations

i

. The inspectors determined that the radwaste control room operator was

i knowledgeable. The' operator knew the reasons for each alarming condition and

was aware of plant conditions that impacted radwaste.

!

I

i 5

4

b

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

. .

Unit 3 Refueling Shutdown

The inspectors observed the Unit 3 shutdown for the refueling outage including the

heightened level of attention (HLA) briefing and operator actions both inside and

outside the control room. The inspectors noted excellent three-way

communications and operator self-checking throughout this shutdown. Reactor

engineering was in close attendance in the control room to assist the o,3erators in

maintainiag close control of reactor core parameters. The unit supervisor was in

control of the evolution and was in frequent commurication with the shift manager.

The operators completed the shutdown in a controlled sequence until the reactor

was manually tripped at 2:29 a.m., March 29th, starting D3R14.

Unit 2 Forced Shutdown

The inspectors monitored the forced shutdown of Unit 2 caused by the declaration

of all 4-kV Merlin-Gerin breakers being inoperable on April 10 (See Section E2.1).

The inspectors observed that the licensee removed all operator distractions during

the shutdown and restricted control room access. Senior management and site

quality verification (SOV) personnel were present in the control room during the

shutdown. For those activities observed, the inspectors noted good communication

between the unit supervisor (US) and the nuclear station operators (NSOs) in that

each step was discussed and thoroughly understood before the step was executed.

Excellent three-way communication was used for all commands and answers, both

within the control room and between the control room and operators external to the

control room. The operators maintained an even rate of power decrease and

followed the shutdown procedure.

The licensee continued a controlled shutdown to a low power level, including

placing the plant in a stable condition for shift turnover at 6 a.m., and then

manually tripped the reactor. Before tripping the reactor, the crew reviewed the

expected responses and actions. The crew also staged the Dresden Emergency

Operating Procedure (DEOP) in anticipation of entry on reactor vessel (RPV) level

due to level perturbations caused by a reactor trip. The crew performed correctly,

and followed the DEOP while restoring level to a normal band.

Subsequently, the operations managers reviewed the shutdown and concluded that

starting at a lower reactor vessel level would improve level control following a trip

from a low reactor power.

Containment inerting and Venting

On lt'. arch 29, during the Unit 3 refueling shutdown, at 4:06 p.m., the licensee

com nenced de-inerting drywell and torus with the plant still producing 381

megawatts electric (MWe) power. This evolution involved equalizing the pressure

between the torus and drywell and then ventilating the drywell and torus (to

remove the nitrogen atmosphere and replace it with normal oxygen content air). At

6

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

..  !

..

!

'

!

i

about 10:00 p.m., an inspector noted that the licensee was simultaneously l

ventilating the drywell and the torus through the 18-inch main valves, not through )

the 2-inch bypass valves. The inspectors informed the shift manager that a similar I

operation at the LaSalle Nuclear Power Plant had been the subject of an immediate l

notification to the NRC on February 20,1997, because it potentially caused the i

plant to be outside of its design bases. The shift manager agreed to look into the  !

question and to assess the applicability to Dresden operations. l

l

! On April 11, during the Unit 2 forced shutdown, the operators started to de-inert  !

l the drywell and torus (ventilate to remove the nitrogen atmosphere). The

! inspectors immediately asked if the US was aware of the questions about de .

inerting at power (that the NRC had informed the operators about during the Unit 3

shutdown on March 28), and that the procedurally controlled configuration for de-

inerting bypassed the function of the suppression pool. Neither the US nor the shift

manager was knowledgeable of the issue. After discussing the issue and reviewing

l

the shutdown procedure, the shift manager and the Unit 2 US decided to shutdown

l and cooldown before ventilating the drywell and torus. The shutdown procedure -

l did not specifically address venting the torus and drywell simultaneo ., De-

inerting the drywell and torus are discussed further in Section E1.1 o' the report.

! t

l c. Conclusions

For those activities observed, the inspectors concluded that the operating crews

,

. performed major evolutions, such as the two unit shutdowns, in a controlled

l manner. The crews were observed to anticipate the plant responses to various

L evolutions and tests.

The inspectors were concerned that the operating crew on shift for two shutdowns

were not aware of issue pertaining to the method of inerting and deinerting the

containment that was identified at another licensee's facility (LaSalle). During each 4

l

l shutdown, the inspectors identified to the operators the potential to bypass the

suppression pool during an accident. See Section E1.1'of this report.

l

-08- Miscellaneous Operations issues (92700)

. 08.1. (Closed) LER 50-237/97-004: Channel Checks for ATWS Level and Pressure

instruments Performed at incorrect Frequency due to Personnel Error During the

Procedure Review Cycle. The LER documented the discovery by the licensee that

!- - channel checks required every shift by TS Table 4.2.B-1, "ECCS Actuation .

Instrumentation Surveillance Requirements," and 4.2.C-1, "ATWS-RPT

Instrumentation Surveillance Requirements," were being performed daily instead of ,

shiftly. This condition existed from January 13,1997, when upgraded Technical 'l

.

Specifications (TSUP) were implemented, until February 8,1997, when it was l

l discovered by the licensee during routine review. The daily checks did not identify.  !

I any problems; therefore, the licensee concluded that the safety impact of this event l

l was minimal. The licensee identified poor procedure review during the change to I

= TSUP as the cause of the event. The licensee reviewed all operator rounds

procedures and found no other errors. Previous reviews of procedures changed for

. .

! 7

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

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

4

. .

.

TSUP by the NRC (inspection reports 50-10:237:249/96009 Section 03.3) have

not identified any omissions. The inspectors assessed the corrective actions and i

l concluded they were sufficient to correct the operator rounds. i

Failure to assure that the rounds procedures required the necessary TS checks was

l considered a violation of 10 CFR 50, Appendix B, Criterion V, " Instruction,

'

Procedures, and Drawings." However, the inspectors leviewed the corrective

actions and viewed this as a Non-Cited Violation, consistent with Section Vll.B.1 of

the NRC Enforcement Policy (NCV 50-237:249/97006-01(DRP)).

08.2 (Closed) LER 50-237/97-006 SRO Absent from the Main Control Room due to Loss

of Focus on Interim Duties. The LER documented the discovery by the licensee that

the Unit 3 Unit Supervisor left the control room for about 6 minutes and thereby

caused non-compliance with TS 6.2.B. This issue was previously discussed in

inspection report 50-237:249/97004 Section 01.3, wherein it stated that final

review would be done upon receipt of the LER. Review of the LER revealed no new

' issues.

Failure to maintain adequate control room staffing was a violation of TS 6.2.B..

This licensee-identified and corrected violation was being treated as a Non-Cited

Violation, consistent with Section Vll.B.1 of the NRC Enforcement Policy.

(NCV 50-237/97006-02(DRP)) l

II. Maintenance

M2 Maintenance Material Condition of Facility and Equipment

M2.1 U3 Hioh Pressure Coolant Iniection Turbine (HPCI)1

Durin0 a plant tour on March 24, the inspectors found that staging had commenced

on the U3 HPCI turbine in preparation for D3R14. The outage was scheduled to

commence on March 29th. Most of the removable lagg'ng pads had been removed

and stacked near the walls in the U3 HPCI room. Addit onally, scaffolding had been

erected around the turbine and numerous hand tools were scattered on the turbine

and associatad piping. The inspectors followed up with the US and the system )

engineer and determined that the work performed did not render the U3 HPCI j

inoperable; however, degrading the condition of the HPCI unit before the start of l

the outage, and doing it without the unit operator's cognizance, was considered a

poor practice.

M3 Maintenance Procedures and Documentation

M3.1 Procedure Adecuacy (61726, 62707)  !

!

l-

i

l

The inspectors performed a review of DlS 1200-02, " Unit 2 Isolation Condenser

l Steam / Condensate Line High Flow Calibration," Rev.18, and compared it with

i 8

. .~. .- ..- -. - . -. - - - - - _ _ . - _ -.- .-.-. . . . . .

.

. . . .

L. .

,

i ..

UFSAR Sections 5.4.6, 7.3.2, 7.3.4, and reviewed DIS 0250-01, " Main Steam Line

High Flow isolation Switch Calibration," Rev.14, and compared it with UFSAR

Sections 6.2.4,7.3.2, and 7.3.1. The procedures were also reviewed against the

TS and the prints. No problems were identified.

( .M4 Maintenance Staff Knowledge and Performance

a. insoection Scone (61726,62707)

The inspectors observed various maintenance activities and assessed the workers'

,

performance and compliance with plant requirements and management

! expectations. The inspectors observed all or portions of the following work

activities and work requests (WR):

l

WR 960111265-01 repair PS-3-4741-29A

l WR 910056406-01 repair 2C condensate - condensate booster pump

WR 970034196-01 3A instrument air compressor, troubleshoot

l

WR 950064442-10 U3 feed regulating valve modifications

WR 950060451-01. repack 3B motor generator set couplings

WR 970035394-01 U2 CRD "A" flow control valve

WR 970002200-01 U3 quarterly TS station battery surveillance

WR 970029446-01 U3 24/48 Vdc battery charger float voltage problems

WR 970039778-01 inspection of Merlin-Gerin breakers in bus 24

WR 970039779-01 inspection of Merlin-Gerin breakers in bus 23

'

WR 970042480-01 install modification on U2 Merlin-Gerin bkrs.

WR 970028352 EPA 2AB-1 and AB 1&2 found tripped

I

WR 940097681 A SBGT Tm Fan 2/3 A suct AO viv

WR 960044107 D318M TS LPCI Dish Header Flow (min flow bypass) )

!

The inspectors observed all or portions of the following surveillance activities and

assessed the workers' performance and compliance with plant requirements and

management expectations.  !

l

DES 8300-17 U2(3) quarterly station battery inspection  :

DES-6601-01 Diesel Generator Governor Oil Change and Compensation  !

Adjustment,

DIS-0500-07 turbine first stage pressure 45 percent scram bypass ,

DIS-1200-02 U2 isolation condenser steam / condensate line high flow '

calibration

DIS-0250-01 main steam line high flow isolation switch cal

,

DOS-0400-02 rod worth monitor operability l

'

DOS-1400-05 2B core spray full flow test  !

DOS-6600-01 - Diesel Generator Surveillance Test (Unit 2)

!

, l

l

l 9

l l

_ , , _.  ;

.

. .

.

b. Observations and Findinos

With the exception of coordination issues, maintenance activities were thorough

and satisfactorily performed. All observed work was performed with the work -

.

s

package present and in active use. . Supervisors and system engineers monitored

job progress and appropriate radiation control measures were in place. When

questions arose or problems were encountered, the workers stopped the activity

and discussed the problems with management who then devised action plans to

resolve them.

The inspectors observed that maintenance activities that took place or impacted the

control room were done so as to minimize the impact on operations. The

maintenance staff were observed to be very quiet and non-intrusive in their I

approach to operations. This assisted in reducing distractions to the operators.

The workers were observed to verify their electrical OOS isolations and to follow

their procedures. Discussions with the workers showed familiarity with

management expectations. The inspectors noted that nianagement was present or

checked on the progress of the work.

Some work coordination problems were observed on the standby gas treatment

(SGBT) system work (WR 940097681) that resulted in additional TS LCO time.

While observing work on the SBGT system, the inspector noted that work on a

support was coincident with work on a controller, and the workers physically were

in each others way. Discussions with licensee management present at the job

revealed that when a similar modification was done on the other train of SBGT, a

lesson learned was that some of the support work could be done prior to entering a

TS LCO for inoperable standby gas treatment, but that this lesson learned was not

incorporated into the current work. More coordination problems were noted by the

inspector during review of control room logs. The logs noted that a planned run for

valve profiling was canceled when it was determined that maintenance staff was

still working on the new controller. The logs indicated that the tracking of the work

was hampered because the work did not require an out of-service (OOS). The

inspector concluded that for the work on the SBGT system, the licensee had not

incorporated lessons learned, but was actively attempting to track problems for

potential improvements.

The inspectors also noted 2 instances of workers standing on piping while erecting

scaffolding. This resulted in denting of the insulation for the piping. This issue was -l

discussed with licensee management, who indicated that standing on piping did not l

meet management expectations, j

l

The operators were observed to plan ahead for expected alarms. For example, the

NSOs reviewed the Dresden annunciator response procedures (DANs) prior to

execution of surveillance tests that were expected to cause the alarms.

Performance of DOS O202-02 R.17 Daily (shif tly) core flow / jet pump surveillance

was assessed and found to be correct. Additionally, the operator was

knowledgeable of changes to the procedure that resulted from the core flow

10

!

!

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

l

i j

.

calibration problems. See Section E8.1. The inspectors observed partial

performance of U3 Quarterly LPCl/CCSW runs and determined them to be in

accordance with procedure.

4

c. Conclusions

The work observed was performed correctly. No instances of incorrect work were

noted by the inspectors. The workers observed had the necessary procedures and

were following them. No inadequacies were noted in the procedures.

M4.5 Unauthorized Temoorarv Alteration to Unit 3 24/48 Vdc Batterv

,

a. Insoection Scone

During a plant tour on March 24, the inspectors discovered an unattended digital

voltmeter installed across the output terminals of the U3 24/48 Vdc battery. As a l

result of a fluctuating high voltage on the 24/48 Vdc Battery Charger, the licensee

installed the voltmeter to monitor the charger output voltage. The inspectors  ;

reviewed the following documents to determine if the voltmeter was authorized to l

be installed and left unattended: i

e WR 970029446-01, "24/48 Vdc Battery Charger, Voltage High and

Fluctuating"

• Engineering Assessment (EA) 0005369049, "3A 24/48 VDC Voltage

Fluctuations"

e 10 CFR 50.59 safety evaluation No. ' 997-01-065

• 'WR 970002200-01, "D3 QTR Tech Spec Station Battery Surv"

i b. Observations and Findinas

On March 14, the 3A 24/48 Vdc battery charger output had drifted up to 30 Vdc

(the acceptable high float voltage was 27.0 Vdc). The inspectors assessed the

troubleshooting plan and proposed course-of-action and concluded that it was

, logical and thorough. The operators had maintenance adjust the battery charger

output voltage down as far as it would go,27.6 Vdc. This voltage was analyzed

by engineering and found to be acceptable until the planned shuidown for the

refueling outage starting on March 29th. After finding a digital voltmeter installed

across the battery on March 24, the inspectors interviewed a U3 unit supervisor

,

(US) about the voltmeter's purpose. The US was unaware that the voltmeter was

installed. In response to the inspectors query, the operators checked the temporary

alteration records and did not find any authorization for the voltmeter installation.

On March 25, the charger voltage suddenly went low and operatiuns declared the

float charger inoperable, even though the voltage was adjusted back into the normal

range using the installed potentiometer -- the same potentiometer that had

11

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

.

. .

t

t .

i l

previously been used to bring the voltage down. The licensee entered a TS LCO

'-

and was preparing to shut the unit down until safety evaluation 1997-01-065 was

completed and the 24/48 Vdc battery charger was shifted to the equalize charge

'

mode and the equalize voltage output reduced to the float voltage. The inspector

[ . was informed that the digital voltmeter was removed as part of the work to adjust ,

the equalize charge voltage output. l

1 .

l

!: The inspectors review of procedures and work requests determined that the  !

'

voltmeter was not authorized to be installed across the output terminals of the U3  ;

24/48 Vdc battery. Technical specification (TS) 6.8.A required, in part; the 1

implementation of procedures meeting the recommendations in Appendix A,  !

j. Regulatory Guide 1.33, Revision 2. Procedure DAP 05-08, Rev. 07, Control.of l

Temporary System Alterations, Section 3.b(1) allowed installing test equipment in

accordance with an approved procedure or Engineering approved work package,

l provided the troubleshooting or test was performed within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and test j

! equipment was attended (except short duration for break time or job turn-over i

l. time). Installing a digital voltmeter across the 3A 24/48 Vdc battery without

{ authorization (procedure or work request) and leaving Iristalled test gear unattended

.wes a violation of TS 6.8.A (50-249/97006-03(DRP)).

c. Conclusions

i The troubleshooting of the high/ low voltage condition on the 24/48 Vdc battery  :

I charger was good. However, the placement of a voltmeter across the battery to l

2 monitor voltage was not handled as a temporary system alteration or authorized by l

-

an approved process, and leaving the voltmeter unattended did not meet procedural l

requirements. l

lit. Enaineerina

l

E1 Conduct of Engineering

i

E1.1 Containment Ventilation issues

a. Insoection Scone

During the March 28th Unit 3 refueling shutdown, the inspectors discussed  !

'

concerns about torus and drywell de-inerting and ventilating with shift

management. These issues had been reported by the LaSalle Nuclear Generating  ;

'

Station in a prompt report on February 20,1997, and had been discussed at a

morning management meeting at the Dresden station on February 21,1997.

1

After observing the shutdown for the refueling outage, the inspectors reviewed the

technical specifications and the UFSAR for applicability to the licensee's practices

for de-inerting and ventilating the torus and drywell including: (1) TS 3.7.K.3,

" Suppression Chamber;" (2) UFSAR Section 6.2, " Containment Systems;" (3)

LaSalle Station LER (50-373/97005-00), " Potential Loss of Both Trains of SGTS

12 i

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

._________._v _ _ _ _ _ _ . _ -

e .

j . . i

i  !

i

'

'

,[ stand-by gas treatment system] and Containment Pressure Suppression During the

First 10 Seconds of a LOCA [ loss-of-coolant accident] Due to Deficiencies in 1

l Original Design Analysis and Procedures;" and Dresden Operating Procedure (DOP) ' [

1600-07, " Primary Containment De-inerting."

l

4

-

b. Observations and Findinos

. .

.

The LaSalle Station staff had identified that venting the torus (or suppression pool l

i: for_ the LaSalle design) and drywell simultaneously through the main ventilation >

,

valves while the reactor is not in cold shutdown raised three concerns regarding a

postulated loss of coolant accident (LOCA): ,

s

.

-

1) a release to the atmosphere during a LOCA as pressure peaks in about  !

d

2 seconds; the UFSAR stated that the isolation valves take 10 seconds to }

c close, l

?

,

-

2) the pressure peak in the drywell and torus would be higher due to the high

energy steam pressurizing the torus instead of being condensed in the water i

, in the torus, and

t

l 3) the SBGT supply valve from the combined ventilation piping could be

'

damaged by the pressure pulse from a LOCA and become inoperable,

. preventing SBGT from being used to mitigate the effects of a LOCA.

During the Unit 3 refueling shutdown, the inspectors questioned the operating crew i

j about the status of the venting concern. The operators were unaware of the

, concerns until questioned by the inspectors on March 28th. See Section 04.1 of

this report.

!

} During a meeting with station management on March 31, the inspectors were .

, informed that these concerns had been addressed for Dresden in a 1982 NRC

- Safety Evaluation Report (SER). The inspectors requested additional discussions on

the specific content of the SER. On April 4th, the inspectors determined that the

o concerns had not been answered by the SER and informed the licensee. Between

the 4th and the 10th of April, engineering made no notification to the operations

J

- department that there was still an open issue with the current de-inerting practices

"

. at Dresden.-

i

'

While shutting down Unit 2 on April 11, the operators started to de-inert at power  ;

again until the inspectors informed the unit supervisor and the shift manager that i

}

the concerns about the de-inerting procers (using the 18-inch valves between the

drywell and torus simultaneously) had r.ot been answered by engineering. After

some discussion among themselves, Me US and SM decided to return the drywell  ;

,  : and torus to the normal at-power corfiguration and to postpone de-inerting until i

~

after the plant was cooled down.~ Tho shutdown procedure did not require that the

containment be de-inerted at power.

I'

13

_ _ _

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

-

1

. .

!

l

'

l

Operations should have known that the question was not resolved. Regulatory

assurance knew on April 4 that a 1982 SER had not resolved the questions about

,

having the drywell and torus open to the atmosphere at the same time. This issue

! of using the 18-inch valves between the drywell and torus simultaneously at power

is an unresolved issue pending inspector review of the impact this had on plant

design requirements (URI 50-237:249/97006-04(DRP)).

c. Conclusions

The inspectors concluded that the licensee did not take proactive action to address

a concern identified at the LaSalle station. During two shutdowns, the inspectors

had to inforin the operating crews that the issue was a concern at Dresden. This

resulted in the operating crew changing the de-inerting during the shutdown after

l being informed by the inspectors.

l

The licensee did not communicate the issue well between the various departments.

'

Although regulatory assurance and engineering were aware, the departments did

~

not keep the operating crews informed. Additionally, representatives of operations

were aware of the issue from the corporate call, but did not assure its resolution.

E2. Engineering Support of Facilities and Equipment

E2.1 4-kV Breakers (71707)

a. Insoection Scooe

On April 4,1997, the plant staff received notification from the licensee's -

Quad Cities Nuclear Power Plant that defects had been discovered in the mounting

of an auxiliary switchpack on Merlin-Gerin (MG) 4 kV breakers that were being

prepared for installation. Engineering determined that no defects had been noted

l previously in the MG breakers at Dresden.

b. , observations and findinas

inspections of spare breakers at Quad Cities revealed some flaws and cracks in the i

contact assemblies. . in response, Dresden personnel performed similar inspections. l

The licensee first inspected breakers that were open. Cracks were found on seven

- out of ten open breakers on Buses 23 and 24. The licensee sent spare breakers to

be analyzed and assessed to determine what affect the cracks had. Preliminary

analysis showed that the cracks did not propagate under service. l

.

Next, the licensee inspected breakers that were closed. This included the feed  !

breaker from bus 23 to bus 23-1 and found a broken auxiliary contact switch l

assembly. Additionally, the breaker had a hanging action request to repair a local  !

,

indication flag that turned out to be a symptom of the cracking. The inspectors ,

'

l followed up on an action request (AR 960069413) that had been written in

October 1996 on the flag indicating improperly. The AR had been canceled in

- January 1997 with a statement that the " breaker indication was verified as being

14

u

!

. . - - - . _

- .

. . - _ .- - . _ -

.. . _ _ _._ _ _ _ _ _ . _ _ _ _ _ . _ _ __ _ _ _ _ _ _ ._

. _

'

"

correct. Def tag was removed." This was incorrect; the indication was skewed

and the tag was still present. A search of AR records, both active and canceled,

did not reveal any other ARs on safety related breakers.

,

'

The Unit Supervisor logs recorded that at 7:38 p.m. on April 10, upon receipt of

information that the breaker inspection revealed a failed auxiliary switch on the feed

breaker, the Shift Manager ordered a shutdown. At 9:12 p.m., the Shift Manager

met with engineering personnel and determined that all the Merlin-Gerin breakers

were suspect, and subsequently declared inoperable,

i .

..

l On April 11, the licensee tripped the reactor and entered Hot Shutdown at

8

57 a.m., and Cold Shutdown at 6:20 p.m. These times were within those j

-

allowed by the TS action statements. After the plant was shutdown, the licensee i

'

tested the bus.23 to bus 23-1 feeder breaker. Except for the local mechanical

l position-indicating flag, the breaker operated as expected, including remote

L indicating lights.

On April 14,1997, inspectors from NRC Headquarters (NRR) met with the

licensee's staff at the System Materials Analysis Department (SMAD) facility and

reviewed the actions taken by the licensee to determine the root cause of the

cracking of auxiliary switches installed in 4.16 kV, M-G circuit breakers at Dresden

and Quad Cities. The inspectors observed some of the breaker testing. The

inspectors also examined some of the faistd breakers from Quad Cities and

reviewed the licensee's proposed interim corrective action and development of

permanent corrective action in consultation with the breaker supplier and the

! manufacturer. The results of this inspection are documented in Quad Cities

Inspection .'.. sport 50-254:265/97006(DRP). Corrective actions for the breakers

were being developed at the close of this inspection.

c. Conclusions

!- The potential failures of the contacts in the Merlin-Gerin breakers caused the

licensee to declare the containment cooling service water system, offsite power,

and other equipment inoperable. The licensee approach to determining the extent

and effects of breaker problems was thorough and technically sound. The decision

to shut down was based on discovery of deficiencies on a TS-related closed

breaker.

E4 Engineering Staff Knowledge and Performance

.

E4.1 Enaineerina Surveillance Procedure Performance

a. Insoection Scooe

The inspectors reviewed the licensee's performance of Dresden Engineering

Surveillance (DES) 6600-01, " Diesel Generator Governor Oil Change and

o Compensation Adjustment," Revision 10, after an attempt to adjust the emergency

l diesel generator (EDG) compensation using the previous revision had resulted in the

- ,

!- 15  !

o  ;

i

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

. _ _ _ _ - - . - - _ - _ . _ . _ . . _ _ _ _ . _ . _ - _ . .- - . _ _ _ . _ _ . - - _ ~ _ _

.

. .

-

,

EDG tripping on low water-pump pressure. The inspectors attended the pre-job

briefing and observed the licensee staff adjust the governor compensation on

March 26th.

!

l,

b. Observations and Findinas

! ' During surveillance test DES 6600-01 on the previous day, the EDG had started

! " hunting" (engine speed surging up and down) after the governor set had been

4

adjusted to yield a 60 hertz (HZ) generator frequency on starting versus the j

l previous setting of 61 HZ. This change was necessary due to implementing the I

upgraded TS. The EDG tripped on low water-pump discharge pressure when the

EDG speed was lowered from the control room in preparation for adjusting the

[

' compensation.

,

i Procedure DES 6600-01, Revision 10, had been implemented to switch two

l procedural steps and to shift the control to " LOCAL" before lowering the engine

l speed in preparation for setting the compensation. Tt.e automatic engine trip on

! low water-pump pressure was bypassed by placing the LOCAL - REMOTE switch to

LOCAL. The equipment attendant and the mechanics set the compensation'without

incident at low speed.

4 The procedure then directed the non-licensed operator (NLO) to return the LOCAL -

j REMOTE switch to REMOTE to return engine speed control to the control-room

j operators. The NLO thought about the action and correctly pointed out to the

j system engineer that the EDG would trip if the switch was moved to REMOTE

4

before the EDG speed was raised above the point where the low water-pump ,

'

pressure trip occurs (about 800 RPM). The system engineer censulted with the US,

'

then told the NLO to raise the EDG speed to 900 RPM. The NLO correctly

1

consulted with the US via radio before raising the EDG speed.

i

j The step to raise the EDG speed before shifting back to REMOTE was not included

j in Revision 10 to DES 6600-01. The inspectors verified that DES 6600-01,

l Revision 10, Step G.8 allowed the governor vendor representative, with the

concurrence of the system engineer, to give verbal changes to the procedure. l

E Subsequent discussions with senior licensee management revealed that verbally

.. adding the step to raise the engine speed to 900 rpm did not meet management's

expectations. Instead, the managero expected that a pen-and-ink change would be  ;

'

made and concurrence documented, before the action was taken. Follow-up  !

inspection revealed that the next procedure revision, issued April 19, included the

l' written change.10 CFR Appendix B, Criterion V. Instructions, Procedures, and

Drawings required that activities affecting quality be accomplished in accordance j

with instructions. ~ This issue is an unresolved item pending inspector review of '

administrative requirements for procedure revisions (URI 50-237:249/97006--

05(DRP)).-

l

i

16 l

l

_ _- _ _ _ ._

.

- . . - - - - . - - . - . - . - . - . - . ~

F. .-

.

! c. Cnog).usions

4

The inspectors identified weak performance by the system engineer in directing the

performance of the engineering surveillance to set the governor compensation on j

the Unit 3 EDG. The inspectors also noted that the procedure that was being j

executed was inadequate. However, the NLO who was operatir.g the EDG j

L -

demonstrated excellent attention-to-detail and a questioning attitude and prevented l

L a trip of the EDG.

_

!

,

!

E8 Miscellaneous Engineering issues (92902) 1

.

- E8.1 (Closed) Unresolved item 50-249/97004-02

Core flow mismatch during startup of I

i Unit 3 revealed that engineering had used the wrong data for the cold calibration of )

] core flow. This item was open pending review and assessment of the final root l

cause. The licensee completed the root cause report (249-200-97-00200), and the i

I

inspector reviewed'and discussed it with knowledgeable personnel. The inspectors i

also verified that operators were aware of the issue and, of the corrective actions, l

'

and verified that procedures were ade'q uately changed. The licensee's root cause l

1 investigation appeared thorough, and the corrective actions taken by the licensee l

, _ appropriate. The primary root cause was inaccurate translation of design data into

l procedures.

The failure to translate the plant design into appropriate procedures was considered

i a violation of 10 CFR Part 50, Appendix B, Criterion lil, " Design Control." ,

i However, the inspectors reviewed the corrective actions and viewed this as a Non-  !

1 Cited Violation, consistent with Section Vil.B.1 of the Enforcement Policy (NCV 50-  !

! 249/97006-06(DRP)). 1

i i

!

4

IV. Plant Suonort ,

1

5

)

j R4 . Staff Knowledge and Performance in RP&C

'

.

i]

R4.1 Radiation Worker Performance (71750) i

The inspectors noted that the " greeter" program continues to be used to enforce

_

l plant rules. The greeters were used to quiz most workers before they were allowed

i .into the radiologically controlled area. Personnel who are not adequately prepared I

i~ _ to enter are retrained, and the subject of a problem identification form (PlF).

_ During routine tours, the inspectors did not identify any workers using unsafe

radiological practices. The inspectors did discover evidence of one inadequate exit

of the radiological area. Specifically, a digital personal radiation monitor was still

logged in, but was on the storage rack. The licensee dealt with the issue

5. appropriately.

p

i

!

17 I

i

I

.

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

, . l

1

.

R8 MisceBaneous RP&C lasues

R8.1 (Closed) LER 50-010/97-001: Loss of the Main Chimney Alternate lodine and

Particulate Sampling System due to a breaker trip caused by an apparent

msgpment deficiency. The LER documented the discovery by the licensee that

tht AMt 1 main chimney was unmonitored for radioactive releases due to a breaker -

t6ip., On February 10, the main chimney monitor system was removed from service

l,

'

for calibration and the alternate iodine and particulate sampling system was placed

in service as required by Unit 1 TS 4.8.E.1.b. The 120 volt breaker that fed power

to the alternate system was found tripped, but was successfully reset during the

system startup. No investigation into the cause of the trip was done at this time,

l- and no action request was written. The technician observed the system running for

about 10 minutes.

The next day, a chemistry technician discovered the breaker had tripped, contacted

the operating shift, and commenced restoration. _ The system was potentially

inoperable and not in compliance with TS 4.8.E.1.b. for about 21 hours2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br />. During

that time, other systems that monitor Unit 1 indicated no releases.

The licensee determined that area lighting plugged into wall-outlets on the same

[ circuit as the sampling system caused an over current that tripped the breaker. As l

!-

corrective action, the other loads were removed and the circuit dedicated to -

l powering the Alternate lodine and Particulate Sampling System.

l The LER stated that the system had apparently been powered from the non-safety-

l related circuit since 1959. At the close of this inspection period, the licensee was

l analyzing what requirements the system needs for a permanent change. The

l licensee also committed to review power supplies to safety-related and TS-required  :

equipment for similar deficiencies. Additionally, the technician who reset the l

l tripped breaker without an investigation was disciplined.

!

The inspectors reviewed the immediate and long-term corrective actions in the LER

and determined them to be adequate.

'This licensee-identified and corrected violation was being treated as a Non-Cited I

Violation, consistent with Section Vil.B.1 of the NRC Enforcement Policy.

(NCV 50-237:249/97006-07(DRP)) .

!

S4 Security and Safeguards Staff Knowledge and Performance

l

S4.1 Fire Watch Performance (71750).

Due to a temporary alteration to provide cooling to the auxiliary electric equipment

l room (AEER), the fire doors and security doors to the AEER and adjoining areas

! were blocked open. Station security personnel were assigned to monitor these

j doors and to act as fire watches. The inspectors monitored the performance and

'

quizzed the personnel about what to do in the event of a fire. The security

' personnel were found to be knowledgeable of their duties.

( 18

l

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

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

l .

. .

'

I

VI. Management Meetings l

X1. Exit Meeting Summary

,

'

The inspectors presented the inspection results to members of licensee

,

management at the conclusion of the inspection on April 18,1997. The licensee

l acknowledged the findings presented.

!

The inspectors asked the licensee whether any materials examined during the

i inspection should be considered proprietary. No proprietary information was

identified.

!

l

l

i-

.

!

!

!

l

!-

!-

l

l

r

3

19

L

l

_

.

. .

!

.

PARTIAL LIST OF PERSONS CONTACTED

l

Licensee

S. Perry, Vice President, BWR Operations

C. Howland, Radiation Protection Manager

E. Connell, Design Engineering Superintendent

T. Foster, Work Control and Outage Manager ,

J. Williams, Acting Plant Engineering Superintendent l

J. Heffley, Units 2 and 3 Station Manager

T. Nauman, Unit 1 Station Manager

S. Barrett, Operations Manager

P. Swafford, Unit 2/3 Maintenance Superintendent

P. Tzomes, Support Services Director

R. Freeman, Site Engineering Manager

l

F. Spangenburg, Regulatory Assurance Manager  !

D. Winchester, Safety Quality Verification Director l

l

lNSPECTION PROCEDURES USED '

IP 37551: Onsite Engineering

IP 40500: Effectiveness of Licensee Controls in Identifying, Resolving, and Preventing

Problems

IP 62707: Maintenance Observations

IP 61726: Surveillance Observations

IP 71707: Plant Operations

IP 71750: Plant Support Activities

ITEMS OPENED, CLOSED, AND DISCUSSED

Ooened

50-237:249/97006-01 NCV Channel Checks for ATWS Level and Pressure

Instruments Performed at incorrect Frequency due to

Personnel Error During the Procedure Review Cycle.

50-237/97006-02 NCV SRO Absent from the Main Control Room due to Loss l

of Focus on Interim Duties.

50-249/97006-03 VIO digital voltmeter across the 3A 24/48 Vdc battery  ;

without authorization and/or leaving installed test gear {

unattended was a violation of TS 6.8.A. '

50-237:249/97006-04 URI deinerting drywel! and torus

50-237:249/97006-05 URI changes to a surveillance procedure 1

50-249/97006-06 NCV Core Flow Mismatch.

50-237:249/97006-07 NCV Loss of the Main Chimney Alternate lodine and

Particulate Sampling System due to a breaker trip

caused by an apparent management deficiency

20

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

l

'

.

l

l

l

4

. ,

l

Closed

50-010/97-001 LER Loss of the Main Chimney Altemate lodine and

Particulate Sampling System due to a breaker trip

caused by an apparent management deficiency. i

50 237/97-004

'

LER Channel Checks for ATWS Level and Pressure

instruments Performed at incorrect Frequency.due to  !

Personnel Error During the Procedure Review Cycle.

50-237/97006 ]

LER SRO Absent from the Main Control Room due to Loss

of Focus on Interim Duties.

50-237:249/97006-01 NCV Channel Checks for ATWS Level and Pressure

Instruments Performed at incorrect Frequency due to

Personnel Error During the Procedure Review Cycle.

50-237/97006-02- NCV SRO Absent from the Main Control Room due to Loss

of Focus on Interim Duties.

50-249/97004-02 URI Core Flow Mismatch.-

-50-249/97006-06 NCV Core Flow Mismatch.

l 50-237:249/97006-07 NCV Loss of the Main Chimney Alternate lodine and

! Particulate Sampling System due to a breaker trip

caused by an apparent management deficiency.

Discussed

None

-1

LIST OF ACRONYMS USED l

!'

ACAD Atmospheric Containment Atmosphere Dilution

BRC Business Review Committee  !

CCST Contaminated Condensate Storage Tank  ;

CCSW Containment Cooling Service Water i

CFR Code of Federal Regulations

CR Control Room  ;

DAP Dresden Administrative Procedure

DATR Dresden Administrative Technical Requirements -

DES Dresden Engineering Surveillance

DGP Dresden General Procedure i

DlS Dresden Instrument Surveillance

DOA Dresden Operating Abnormal

DOE Department of Energy

DOP Dresden Operations Procedure

DOS Dresden Operations Surveillance q

DTS Dresden Technical Surveillance l

ECCS Emergency Core Cooling System

,

EDG Emergency Diesel Generator  !

! EMD Electrical Maintenance Department

l

EOF Emergency Operations Facility

i

21

i

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

_ . . _ . . . _ _ _ . _ ~ . _ . _ _ _ . . _ . _ _ _ _ . _ _ _ _ . . _ - _ _ _ _ _ _ . _ . . _

i

'

l - *

t ,

!

l

. ,

EP Emergency Preparedness l

l ERO Emergency Response Organization

'

FHA Fire Hazard Analysis

FME Foreign Material Exclusion i

gpm Gallons Per Minute

GSEP Generating Station Emergency Plan s

l MPCI High Pressure Coolant injection  :

HVAC Heating, Ventilation, and Air Conditioning (

IFl Inspector Followup ltem  !

IMD instrument Maintenance Department l

1RB lssues Review Board i

kW Kilowatt

kV Kilavoit *

l

LER Licensee Event Report l

LOCA Loss Of Coolant Accident 1

MG Merlin-Gerin i

MMD Mechanical Maintenance Department '

MW Megawatt  !

NCAD Nitrogen Containment Atmosphere Dilution l

NSO Nuclear Station Operator

NTS Nuclear Tracking System

l

1

OSC Operational Support Center I

OE Operability Evaluations

PlF Problem Identification Form

psig Pounds Square Inch Gage 1

PVC Poly-Vinyl Chloride

RPT Radiation Protection Technician

SOV Site Quality Verification

TSC Technical Support Center

UFSAR Updated Final Safety Analysis Report

URI Unresolved item

l

l

l

l

l

l

4

l

i

< l

l 22