ML20147A965

Insp Repts 50-454/96-09 & 50-455/96-09 on 960927-1217. Violations Noted.Major Areas Inspected:Operations,Maint, Engineering & Plant Support

ML20147A965
Person / Time
Site:	Byron
Issue date:	01/10/1997
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20147A958	List: ML20147A953 ML20147A959 ML20147A965
References
50-454-96-09, 50-454-96-9, 50-455-96-09, 50-455-96-9, NUDOCS 9701280378
Download: ML20147A965 (23)

See also: IR 05000454/1996009

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U. S. !10 CLEAR REGULATORY COMMISSION

REGI0t1 III

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Docket Nos: 50-454, 50-455

License Nos: 14PF-37, NPF-66

Report flo: 50-454/96009, 50-455/96009

Licensee: Commonwealth Edison Company

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Facility: Byron Generating Station, Units 1 & 2

Location: 4450 N. German Church Road

Byron, IL 61010

Dates: September 27 - December 17, 1996 i

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Inspectors: S. D. Burgess Senior Resident Inspector

N. D. Hilton, Resident Inspector

M. J. Farber. Regional Inspector, DRS

T. M. Tongue, Project Engineer, DRP

C. K. Thompson, Illinois Department of Nuclear Safety  !

Approved by: R. D. Lanksbury Chief,

Reactor Projects. Branch 3 i

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9701280378 970110

PDR ADOCK 05000454

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EXECUTIVE SUMMARY

Byron Generating Station. Units 1 & 2

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NRC Inspection Report 50-454/96009. 50-455/96009

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-This inspection included aspects of lite..see operations, engineering.

maintenance, and plant support. The report covers a resident inspection  ;

conducted from September 27 through December 17. 1996.

Operations

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The station auxiliary transformer (SAT) switching and restoration

operations were carefully planned and professionally executed. -

(Section 01.3) .

Maintenance

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Maintenance and surveillance activities were completed thoroughly and

professionally. (Section M1.1)

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Surveillance test OBVS SX-5 contained inadequate acceptance criteria to

determine SX system operability. (Section M1.2)

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System engineering failed to appreciate or understand the importance of the

surveillance test with respect to SX system operability. Previous

surveillances documented silt accumulation outside the acceptance criteria

and degraded trash racks since 1993 with no operability assessments

performed. (Section M1.3)

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Heat exchanger inspections and cleaning found minimal silt. (Section M1.6)

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Comprehensive maintenance activities significantly improved the weather

protection of the Unit 2 SAT. (Section M1.7)

Engineerinq

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Based on excessive silt found in the essential service water (SX) cooling

towers on October 15, 1996, engineering determined that the SX system was

inoperable when the plant relied on the deep well pumps for makeup

capability. (Section El.1)

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The design input used in calculating the ultimate heat sink cooling tower

basin makeup did not reflect the SX system design features since initial

plant operation. The 1991-1992 design-basis reconstitution failed to

identify this error. (Section E1.2)

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Engineering did not ap] ear to be knowledgeable of the SX system design as

it was documr ed in tle UFSAR. (Section E1.3)

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The license submittal regarding spent fuel pool (SFP) Boraflex degradation

and the decision to checkerboard the SFP was not pursued in a timely manner

until after discussions with the NRC. (Section E2.1)

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Engineering aggressively pursued the motor control center spacer issue with

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Westinghouse. The operability assessment and corrective actions to install

the spacers was timely and thorough. (Section E2.2)

Plant Sunnort -

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The inspectors identified a worker lying in the Unit 1 positive

displacement charging pump room. During an approximate 25-minute stay. the

individual received undetectable radiation exposure. (Section R1.1)

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The inspectors identified a containment 9 ray fire door blocked open

without a fire barrier impairment pert: A violation was issued.

(Section F1.1)

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REPORT DETAILS

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Summary of Plant Status

Unit 1 operated at power levels up to 97 percent during this inspection

period.

Unit 2 was in a refueling outage (B2R06) until October 4.1996, when the unit

went critical and was placed on the grid October 5. 1996. Subsequently, the

unit operated at power levels up to 100 percent. i

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I. Doerations

01 Conduct of Operations

01.1 General Comments (71707).

- Using Inspection Procedure 71707, the inspectors conducted frequent

reviews of ongoing plant operations. In general, the conduct of

operations was professional and safety-conscious. Specific events and

noteworthy observations are detailed in the sections below.

01.2 Unit 2 Startuo (71707)

The licensee shutdown Unit 2 on August 8. 1996, due to a 120 gallons per

day steam generator tube leak. After approximately 1 week, the licensee

transitioned to the refueling outage, originally scheduled to start

September 7. 1996. During the outage, the licensee completed steam

generator inspections and repairs and a reactor coolant system

resistance temperature detector (RTD) bypass loop elimination

modification. On October 4,1996, at approximately 12:30 a.m. (CDT).

Unit 2 criticality was achieved by diluting the reactor coolant system

baron concentration. Following the performance of low power physics

testing, the unit was placed on the grid on October 5,1996, at

1:56 p.m. (CDT).

01.3 Station Auxiliary Transformer Outage Operations

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a. Inspection Scone

The licensee performed a Unit 2 Station Auxiliary Transformer (SAT) bus

duct inspection as part of the corrective actions from the Unit 1 loss

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of offsite power on May 23, 1996. The inspectors observed portions of

the electrical operations required to restore SAT 242-1 and place SAT

242-2 out of service and to restore Unit 2 to a normal off-site power

electrical lineup after inspection completion. The inspectors also

observed portions of the maintenance inspections performed on the bus

ducts (see Section M1.7).

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b. Observations and findings

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On October 26 and November 2. 1996, the inspectors. observed the SAT

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pre-job briefings. Both briefings were attended by all operators

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involved in the SAT outege and -the planned evolutions were discussed in

L detail. Contingency plans were discussed with dedicated operators

L assigned to complete any.. required actions. Extra operators and shift

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management were available to support the evolutions. . Communications

were clear and concise with questions and answers. The significance of

the evolution and management expectations were discussed.

The inspector also observed emergency diesel generator runs, electrical

bus switching evolutions, breaker manipulations, and out of. service -

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activities. The inspector observed consistent application of three-way

l communications, procedure use and place keeping, and peer checking.

c. Conclusions

The inspector concluded that the SAT switching and r'estoration

operations were carefully planned and professionally exec.uted. l

08 Miscellaneous Operations Issues (92901) ~

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08.1 (Closed) Violation 50/454-94022-02: Station procedure BAP 300-1.  !

" Conduct of Operations " and BAP 330-1. " Station Equipment '

Out-Of-Service Procedure." did not properly verify that the C steam '

generator (SG) was ready for service prior to refilling it. When the

licensee placed the C SG into wet layup after contractor maintenance,

approximately 3600 gallons of secondary side water drained onto the

containment floor. The inspectors reviewed the licensee's corrective  ;

actions that consisted of creating a SG secondary side close-out '

checklist in procedures BMP 3300-14. " Steam Generator Primary Manway

Closure Removal and Installation." Revision 14. and BMP 3300-18. " Steam

7 Generator Secondary Manway/Shell Opening Closure Removal and .

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Installation." Revision 12. The inspectors concluded that the checklist

contained appropriate activities that were required to be performed ,

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prior to returning the SG secondary side to the operations department

for normal system fill or testing following maintenance. The checklist

also established better control of contractor activities. During the

recent Unit 2 outage (B2R06), the checklist was included in the SG work

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request packages with no concerns noted. This item is closed.

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II. Maintenance

M1 Conduct of Maintenance

M1.1 Maintenance Observations (62703)

The inspectors observed all or portions of the following work

activities:

. WR 960094288 Troubleshoot oscillations from 2AF005A.

. WR 960002499 Replacement of RWST access cover gaskets

. WR-960002500 Replacement of RWST access cover gaskets

^ . WR 960101104 Silt removal in SX cooling tower basins A and B

. WR 960108241 Inspect / Clean Unit 1 SI lube oil cooler

The inspectors found that the maintenance activities were conducted in

accordance with approved procedures and were in conformance with

technical specifications. The inspectors observed maintenance

supervisors and system engineers monitoring job progress. Quality

control personnel were also present. When a]plicable, appropriate

radiation control measures were in place. T1e inspectors identified no

concerns as a result of these maintenance observations.

M1.2 Inadeouate Surveillance Test Acceptance Criteria and Test Control

a. Inspection Scope

On October 1.5. 1996, during the performance of surveillance OBVS SX-5.

" Inspection of River Screen House (RSH) and Essential Service Water

Cooling Tower." the licensee identified that silt levels in the

essential service water (SX) cooling tower basins were greater than the

acceptance criteria. The inspectors reviewed surveillance procedure

OPVS SX-5 for technical adequacy and also discussed the results of the

diver's inspection on October 15. 1996. with licensee personnel.

Additional observations and issues related to the silt problem are

discussed in other sections of this report under II. Maintenance and

III. Engineering.

b. Observation and Findings

Inadeouate Acceptance Criteria

The inspectors questioned the validity of the SX cooling tower basin

acceptance criteria listed in surveillance OBVS SX-5. The acceptance

criteria stated that the silt buildup in the SX cooling tower basins ,

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shall not exceed 12 inches at two or more points shown on OBVS SX-5.

Attachment E. Attachment E. which was an illegible diagram of the SX

basins. showed 30 sample locations. The inspectors questioned the

operability of the SX system if all 30 silt sample points were measured

within the acceptance criteria at 11 inches. The licensee agreed that

the procedure was inadequate and could not provide justification for the

surveillance acceptance criteria. The inspectors determined that the

procedure failed to have sufficient quantitative acceptance criteria to

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determine SX system operability based on silt levels in the SX cooling

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tower basins. This is an apparent violation of 10 CFR Part 50, '

Alpendix B, Criterion V. " Instructions. Procedures, and Drawings," ,

-(EEI 454/455/96009-01(DRP)).

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Inadeauate Test Control .

The inspectors were told that the October 15, 1996, silt measurements in

the SX cooling tower basins were taken with reference to the diver's

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boot and arm. The inspectors questioned the appropriateness of this  !

practice since surveillance procedure OBVS SX-5 referenced test

equipment such as underwater cameras and depth gages that may be used -

during test performance. Since the silt measurements wete-used to

determine SX system operability, the inspectors considered the iiver's

boot and arm to be inappropriate measuring devices for measuring the

silt height in the SX cooling tower basins. Failure to use adequate

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test instrumentation to measure the amount of silt in the SX cooling i

' tower basins is an apparent violation of 10 CFR Part 50 Appendix B, i

Criterion XI, " Test Control." (EEI 454/455/96009-02(DRP)). ,

c. Conclusions -

Inadequate acceptance criteria in surveillance OBVS SX-5 could have

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resulted in meeting the stated acceptance criteria for silt levels in

the SX cooling tower basins even though the SX system would not have

been able to meet its design function.

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M1.3 Inadeouate Evaluation and Corrective Action of Past Surveillances

a. Insoection Stone

The inspectors reviewed past OBVS SX-5 surveillance test results for

1993 through 1995 to detennine previous SX basin silting conditions.

b. Observations and Findinas

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Excessive Silt Accumulation

The acceptance criteria for the amount of silt allowed in surveillance

OBVS SX-5 was as follows:

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l * The RSH intake and forebay shall not exceed 9 inches at two points

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along the width of the intake channel.

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. The RSH SX pump sumps shall not exceed 6 inches sediment accumulation

in sumps.

. The SX cooling tower basin shall not exceed 12 inches at two or more

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points.

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The inspectors reviewed the 1993 tL mugh 1996 completed OBVS SX-5

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surveillance tests and identified the following issues:

. On July 26. 1993, the diver recorded 14 areas where silt levels were

12 inches to 24 inches in the SX basin. silt accumulations in one of

the sumps was 10 inches, and RSH intake and forebay silt

accumulations were 24 to 36 inches. Corrective actions consisted of

the diver " distributing" the silt to levels that met the surveillance

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acceptance criteria. No operability assessment for the SX system was  !

performed on the as found silt condition.

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The silt buildup in the SX cooling tower basin changed the volume of

water as analyzed in the UFSAR and therefore could change the

consequences of the design-basis accident bounded in the UFSAR.

Failure to take a)propriate corrective action to the silt 1

accumulation in t1e SX cooling tower basins is an apparent violation

of 10 CFR Part 50. Appendix B. Criterion XVI. " Corrective Action."

(EEI 454/455/96009-03A(DRP)).

. On July 26,199S. the diver recorded silt accumulations of 30 inches

to 4 feet in the RSH intake and forebay area. Silt accumulation in

the SX makeup pump sump measured 12 to 18 inches. The silt was

removed via a vacuum pump. Engineering evaluated the test results on

June 17, 1996. No operability assessment for the SX system was

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performed on the as found silt condition.

Based on previous surveillance results, the inspectors questioned SX

system operability since 1993. The licensee initiated a root cause

investigation into the SX silting issue and planned to address past SX

system operability.

Degraded Trash Rack Gratina

The inspectors also identified that the completed surveillance tests for

1.993, 1994, and 1995 documented that several portions of the trash rack

grating had fallen away from up)er lateral supports or were lying in the

bottom of the SX cooling tower Jasins or leaning against the basin

support columns. The trash rack grating was attached to the anti-vortex

drainage duct located at each end of basin A and B. The trash racks

provided a 4 inch by 1-3/16 inch screen for large debris before entering

the drainage duct and eventually the SX pump suction. The ins)ectors

also noted that UFSAR Section 3.8.4.1.6. Figure 3.8-66, descri)ed the

trash rack grating.

System engineering concluded after each surveillance test that the trash

rack grating was not part of the test acceptance criteria and that a

work request had been previously written in 1993 to restore the grating

in basin A and in 1994 for the same repairs in basin B. No safety

evaluation or screening for potential unreviewed safety questions had

been performed on this change to the SX system. Since the SX cooling

tower basins are classified Seismic Category I, the inspectors also

questioned the effects the degraded grating potentially had on the UHS

seismic qualifications. The failure to take prompt corrective action to

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repair the trash racks is an apparent violation of 10 CFR Part 50.

Appendix B. Criterion XVI. " Corrective Action." (EEI -

454/455/96009-03B(DRP)).

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In November 1996 the licensee replaced the grating and repaired or- '

replaced the necessary support brackets that were also degraded. During

review of the seismic analysis for the SX cooling tower structure the ,

licensee identified an error in the methodology used to determine

seismic response and member stresses in calculations No. 4.2.3 BY and '

3.4.1 BY. The errors were not significant and the licensee planned to

regenerate the calculations.

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c. Conclusions ,

System . engineering failed to appreciate or understand the importance of

the surveillance test with respect to SX system operability. Previous

surveillances that documented silt accumulations outside the acceptance

criteria brings into question the SX system operability since 1993.

Inadequate corrective action to repair the trash racks since 1993 '

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demonstrated a lack of knowledge of SX system design by the licensee and '

a willingness to operate with a-degraded safety system.

M1.4 River Screen House Insoections

a. Insoection Stone

On December 4,1996, the licensee performed an inspection of the RSH. *

The inspectors discussed the diver's inspecticn with licensee personnel,

b. Observations and Findings

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On December 4.1996, with the use of divers the licensee inspected the

RSH for silt accumulation and found silt levels that exceeded OBVS SX-5 i

surveillance acce)tance criteria at several locations. Through

interviews with t1e diver and licensee Jersonnel the inspectors found

the most significant accumulation was t1e 0A SX makeup pump sump which  !

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contained 36 inches of silt where the acceptance criteria was 6 inches. '

The licensee's operability assessment determined that presence of the

silt accumulation did not impede the operability of the pumps to deliver

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the required flow rate. This assessment was based on inservice test t

data (taken every 92 days) that indicated that the pumps were delivering

expected flow rates without exceeding differential pressure

requirements. The data also indicated no signs of pump cavitation. The

l inspectors reviewed the data and agreed with the assessment.

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As discussed in Section M1.3. surveillance OBVS SX-5. performed on

July 26, 1995. documented silt levels of 12 to 18 inches. The silt was

removed via a vacuum pump.

c. Conclusions

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Based on review of the SX makeup pump inservice testing data, the

j inspectors confirmed the licensee assessment that the presence of silt '

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in the sump did not impede the pumps from delivering the required flow

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rate and showed no signs of pump degradation. The excessive silt

accumulation appeared to have taken place over the past 17 months.

M1.5 SX Basin and River Screen House Silt Removal

a. Inspection Scope l

The inspectors observed portions of the silt removal from the SX cooling

tower basins and the RSH. The inspectors discussed the procedure and j

process with licensee personnel and the divers.

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b. Observations and Findings

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To control the cleaning activities in the SX cooling tower basins, the i

licensee wrote procedure SPP 96-067, " Support for Cleaning. Inspection. '

and Repair Activities in the Essential Service Water Cooling Tower

(SXCT) Basins." Revision 0. This special test detailed the system

line-ups needed to support the basin cleaning and also monitored SX

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system parameters before and after the cleaning to detect any effects '

the cleaning might have on the SX system. The silt remov'ed from the ,

towers and the RSH was pumped to tanker trucks, which transported the l

silt to a large earthen basin located just northwest of the plant, j

within the owner controlled area.

c. Conclusions

The inspectors monitored the activities and had no concerns with the

silt removal process. The silt removal activities continued after this

inspection period.

M1.6 Various Heat Exchanger Inspections for Silt

a. Insoection Scone

The inspectors observed portions of small heat exchanger inspections for

silt and discussed the findings with licensee engineering.

b. Observations and Findinas

To ensure that the de-silting activities at the SX cooling tower basins

and the river screen house (RSH) was not adversely affecting plant

equipment, the licensee performed inspections and cleaning of various

heat exchangers cooled by SX water. The inspectors observed minimal

silt in the heat exchangers and agreed with the licensee that heat

exchanger performance was not impaired. The licensee planned to

continue with the inspections on an increased frequency, until the

de-silting was completed and an enhanced inspection schedule was

developed.

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c. Conclusions

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The inspectors found that the inspection activities were conducted in

accordance with approved procedures and were in conformance with

technical specifications. The inspectors observed maintenance

supervisors and system engineers monitoring job progress. Quality

control personnel were also'3 resent. The inspectors identified no 1

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concerns as a result of the leat exchanger inspections since minimal

silt was found in SX heat exchangers inspected.

M1.7- Station Auxiliary Transformer Outaae Maintenance

, a. Insoection Scone

The inspectors observed )ortions of.the maintenance inspections

performed on the Unit 2 aus ducts and discussed the overall maintenance

activities with the SAT outage project manager. These activities were

also reviewed against the Updated Final Safety Analysis Report (UF_SAR)

descriptions.

.b. Observations and Findings

The licensee removed the lower covers for the SAT bus ducts to inspect

for water intrusion. The licensee did not identify any significant

degradation of bus duct insulators. The bus duct caulk was also

inspected and found satisfactory; however, the licensee did add caulk in

several areas to provide additional protection. Additional measures

taken to improve the weather protection included supporting rubber seals

on the transformers to enhance water run off and the addition of a

waterproof tape at exterior junctions of the bus duct.

c. Conclusions

The inspector concluded that the licensee significantly improved the

weather protection of the Unit 2 SAT by the comprehensive nature of the

inspection and enhancements.

ML8 Surveillance Observations

a. Insoection Scone (61726)

The inspectors observed all or parts of the following surveillance and

special test procedures. The inspectors also reviewed plant equipment

and surveillance activities against the UFSAR descriptions.

. OBOS 7.5.e.1-1 Essential Service Water Makeup Pump OA Monthly

Operability Surveillance

1BOS 3.1.1-21 Train B Solid State Protection System (SSPS)

Bi-Monthly Surveillance

180S 3.2.1-941 ESFAS Instrumentation Slave Relay Surveillance

1BOS 7.1.2.1.b-1 1A Auxiliary Feedwater Pump Monthly Surveillance

180S 7.1.2.1.b-2 Unit 1 Diesel Driven Auxiliary Feedwater Pump

Monthly Test

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1BOS 8.1.1.2.a-1 Unit 1 1A Diesel Generator Operability Monthly

Surveillance

1BVS 5.2.f.3-2 ASME Surveillance Requirements for Residual Heat

Removal Pump 1RH01PB

-. 2BVS AF-1 Unit 2 2B Diesel Auxiliary Feed Pump Battery

Bank A Capacity Test

2BVS AF-3 Unit 2 Simultaneous Start of Both AF Pumps With

Flow to the Steam Generators

. SPP 96-067 Support for Cleaning, Inspection, and Repair

Activities in the Essential Service Water

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Cooling Tower (SXCT) Basins

b. Observations and. Findings .

During the 1B SSPS surveillance, the licensee failed to complete the

testing within the technical specification (TS) allowed time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.

Testing was delayed when an operator failed to latch a relay during the

test. The operator pushed the relay button in far enough to actuate the

relay, but did not latch the relay. Issue resolution delayed the

testing. The inspectors noted that the licensee completed the testing,

but appropriately entered the limiting condition for operation action

requirement. TS 3.3.1 action statement 12.b., for an inoperable reactor

trip breaker. TS 3.3.1 action 12.b required the reactor trip breaker to

be restored in 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. the licensee completed the testing in 45 minutes

and exited the action requirement. The inspectors also noted that the

licensee appropriately entered the failure to latch the relay into the

operator workaround program for formal resolution.

c. Conclusions

Observed surveillance activities were completed thoroughly with system

engineers monitoring activities. Difficulties in completing the 1B SSPS

surveillance were appropriately handled with the entry into the TS

action statement.

H8 Miscellaneous Maintenance Issues (92902)

M8.1 (Closed) Inspection Followuo item 50/454-95003-03: Diesel generator

hairline cracks on air intake manifolds were identified during a monthly

surveillance. The licensee's material failure analysis concluded that

the manifolds were overstressed during installation resulting in

material cracks / defects that propagated during engine operation due to

vibration. The licensee installed new intake manifolds on the Unit 1

diesel generator during B1R07. The new manifolds were manufactured to

more stringent fabrication and welding criteria. The manifolds from

i Unit 1 were refurbished by the vendor to the new standards and installed

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on the Unit 2 diesel generators during B2R06. The inspectors noted no

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reoccurrence of the hairline cracks since installation of the

new/ refurbished intake manifolds. This item is closed.

M8.2 (Closed) Insoection Followuo Item 50/454-96003-03: Potential effect of

boric acid corrosion on the carbon steel filtered vent (VF) system due {

to a blocked safety injection (SI) pump drain line. In response to this '

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Concern, system engineering determined that the boric acid corrosion

would be limited to-less than 0.002 inches per year based on boron >

concentrations of 2500 ppm. The VF system is not safety-related and no

operability concerns were noted. The licensee repaired the blocked SI

drain lines This item is closed. ~ '

M8.3 (Closed) Insnection Followun Item 50/454-96007-02: Containment spray

(CS) pump room 1A contaminated due to floor drain plugging. The

inspectors questioned the operability of the safety-related equipment in

the CS and residual heat removal (RHR) rooms with an ' inoperable floor

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drain system, since the UFSAR took credit for the floor drain system to

mitigate the consequences of a flood. In response, the licensee found

only one of two floor drains in the CS and RHR pump rooms plugged.

Based on this configuration, the licensee estimated that during a

design-basis flooding accident, the flood level would be about 5 inches

below the CS and RHR pumps and would be considered operable. The

analysis assumed the flood duration of 30 minutes in accordance with the

UFSAR. Corrective actions included hydrolyzing the floor drains at 4

year intervals and inspect, clean, and test the sump alarms at 5 year

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intervals. This item is closed.

111. Engineerina "

El Conduct of Engineering

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El.1 Excessive' Silting in the Essential Service Water Coolina Towers (37551)

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a. Insoection Scoce

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! The inspectors reviewed the action taken by engineering to determine the

consequences of the silting on the operability of the SX system.

b. Observations and Findings

The licensee identified that silt levels in the SX cooling tower basins

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were greater than the acceptance criteria stated in surveillance OBVS

l SX-5. The acceptance criteria stateu that silt levels were not to

i exceed 12 inches at two or more points. Silt levels at 28 points were

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found to be at 12 to 36 iaches. '

The inspectors review of the licensee's operability assessment found

that the presence of silt in the basin displaced an equivalent volume of

water in the basin. Based on silt measurements taken from both basins,

it was estimated that approximately 48,000 gallons of water were

displaced by the silt. This volume corresponded to a level change of

approximately 15 3ercent on the basin level indicators. The SX cooling

tower serves as tle ultimate heat sink (UHS) for both units and consists

' of two interconnected basins A and B. The water volume in the basin is

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critical as thermal performance of the UHS relies on a specified water

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volume to absorb heat energy from safety-related components cooled by

the SX system. Both thermal and volumetric considerations (which

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include makeup capability) are impacted by the presence of excessive

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silt.

The licensee's o)erability assessment of the thermal performance of the

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UHS determined tlat an adequate volume of water exii.ed in the SX t

cooling tower basin to maintain the SX design temperature below 100 F

for design-basis accident conditions at the TS minimum basin level of

50 percent. <

For makeup capability to the basin, the licensee evaluated the

higher-capacity SX makeup pumps, which corresponded to a TS minimum

water level of 50 percent, and the lower-capacity-deep well pumps, which {

required a TS minimum basin level Qf 82 percent. The makeup capability I

must be sufficient to offset the evaporation rate of the water in the '

cooling tower basin. The analysis concluded that the 15 percent silt

level in the basin had no significant impact on the ability to makeup

the basin with the SX makeup pumps. However, the corresponding

evaluation for the deep well pumps determined that the makeup capability

was inadequate and one basin would run out of water and be incapable of

providing water to the SX system. Therefore, the continued operability

of the UHS and the SX system, when relying on the deep well pumps for 1

makeup capability, would only be assured if SX basin level was

maintained at or above 97 percent to account for the 15 percent silt

accumulation.

1

As compensatory measures the licensee administratively raised the SX

basin levels from 50 percent to 60 percent during normal operations when

both SX makeup pumps were available. The water level limit was raised

from greater than or equal to 82 percent to 97 percent when relying on

the deep well pumps for makeup capability. This reliance occurred when

TS 3.7.5 action statement c, e, f, g, or h were entered. This included

situations when: (1) one or more SX makeup Jumps were inoperable; (2)

when one UHS cooling tower basin level switc1 was inoperable: (3) when

the Rock River water level was forecasted to exceed 702.0 feet: (4) when i

the Rock River water level fell below 664.7 feet or flow was less than  !

700 cfm: .and (5) when a tornado watch was issued for the Byron site. I

The inspectors reviewed maintenance records and operator logs and

determined that the plant relied on the deep well pumps for makeup

capability on July 7 - 12, 1996, during SX makeup Jump, OSX02PB,

maintenance and July 23, 1996, when a tornado watc1 was issued for the

Byron area. Based on the licensee *s analysis, the UHS and the SX system

was considered inoperable at these times.

l

c. Conclusions '

The licensee's operability assessment concluded that the SX system was

inoperable, when relying on the deep well pumps for makeup capability, i

since the basin water volume corresponding to an indicated water level

of 82 percent, reduced by 15 percent due to the presence of silt, was an

inadequate volume of water to support SX operation.

14

.

.

\

l

El.2 Inadequate SX Makeun Calculation  !

.

a. Inspection Scnne

During subsequent evaluations, the licensee identified errors in the UHS 1

cooling tower basin makeup calculation. The inspectors discussed the i

,

error with the licensee to determine the error consequences on SX system  !

operability. '

b. Observations and Findings

!

The inspectors reviewed the licensee's determination that the VHS

cooling tower basin makeup calculation. NED-M-MSD-14. Re. vision 0 3

'

(performed in February 1992) and Revision 1 (performed in August 1992).  !

was based on a usable basin water volume calct 'ated from the bottom of I

the basin. The inspectors found that the actual usable volume for water

1

was limited by the anti-vortex drainage duct that enclosed the SX pump  !

suction pipe. The anti-vortex drainage duct openings were 8 inches

above the basin slab and the makeup calculation did not account for this

8 inches of unusable water volume. The calculation also did not account I

for any silt accumulation. These calculations were performed during the ' '

SX/ UHS design-basis reconstitution effort in 1991 and 1992.

l

With the usable volume reduced 8 inches by the anti-vortex drainage

duct, the licensee determined that the deep well makeup pump would not

have adequate makeup capability when the VHS basin water level was at

82 percent per TS 3.7.5 action statements c. e. f, g. or h.

,

The TS l

water level of 82 percent was an inadequate water volume to ensure UHS i

and SX system operability. The licensee stated that the calculational '

error had existed since initial plant operation. Failure to have

adequate design control measures in place to ensure that the

design-basis of the SX system was correctly translated into

specifications is an apparent violation of 10 CFR Part 50. Appendix B.

Criterion III (EEI 454/455/96009-04(DRP)). ,

I

c. Conclusions

The inspectors concluded that the licensee's design input used in

calculating the UHS cooling tower basin makeup did not reflect the SX

system design features since initial plant operation. The design-basis

reconstitution performed in 1991 and 1992 failed to identify this error. l

E1.3 UFSAR Discrepancies on SX Coolina Tower Desian Features

a. Inspection Scone

The inspectors reviewed applicable sections of the UFSAR to determine if

the SX system was accurately reflected.

b. Observations and Findings

The inspectors identified discrepancies between UFSAR Figure 3.8-66 and

UFSAR Figures 9.2-25, 9.2-26. and 9.2-27. Figure 3.8-66 showed a small

15

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

.

box-shaped screen (trash rack) over the SX pump suction in the cooling

.

tower basin and the other figures showed a large anti-vortex drainage

duct. The licensee investigated the discrepancy and determined that the

box-shaped trash rack was part of the initial SX cooling tower basin

design. The box-shaped trash rack was designed to both prevent trash

from entering the SX pump suction piping and to eliminate vortex  ;

formation at the suction piping. Testing, performed at the University l

of Iowa in 1980, demonstrated that the box-shaped trash rack neither

effectively prevented vortex formation nor provided adequate capacity as

a trash rack. As a result, prior to receiving an operating license, a

design change installed an anti-vortex drainage duct with an attached

trash rack that ran the width of each basin and enclosed the SX pump

suction. The UFSAR drawings had never been updated to show the current '

dssign. Failure to update the UFSAR to assure that the information

1

included in the UFSAR contains the latest material developed is an.

apparent violation of 10 CFR 50.71, " Maintenance of records, making of

reports," (EEI 454/455/96009-050RP)).

c. Conclusions

,

Licensee personnel did not appear to be knowledgeable that a portion of

the as-built SX system design deviated from design as it was documented

in the UFSAR.

E1.4 Additional SX Basin inspections

7

a. Insnection Stone

On November 5 and 6,1996, the inspectors monitored the licensee's

performance of additional SX basin inspections to facilitate the trash

rack grating replacement and repairs.

b. Observations and Findinas

A diver entered SX basin B to better inspect and identify the necessary

l repairs to the trash rack. During the inspection, the diver identified

and removed a 4 foot by 20 foot piece of plastic and tw hard hats.

Based on interviews of the divers the inspectors dete" mined that the

plastic was found crumpled against the anti-vortex drainage duct and the

i

l l

hard hats were found on the basin floor. Because of the uncertainty of i

I

similar material being in the A basin, the licensee declared the SX '

pumps in A train on both units inoperable until an ins)ection could be

performed. On November 6,1996, the diver inspected t1e A basin and

i

found a 4 foot by 20 foot piece of plastic and one hard hat. Based on

the observed condition of the materials found in both basins, the

'

inspectors concluded that the items had been in the basin for quite some

time however, the ins 9ectors noted that the SX cooling tower basin

inspections performed in 1993, 1994, 1995, and on October 15. 1996, did

not identify these items.

i

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16

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

..

i

c. Conclusions

.

.

Based on the additional inspections, the licensee concluded that both SX

cooling tower basins were free from large foreign material that could

potentially block the SX pump suction. The inspectors concluded that

the age of the foreign material found in the basins called into question

the thoroughness of the previous inspections.

E2 Engineering Support of Facilities and Equipment

E2.1 Soent Fuel Pool Boraflex Dearadation

.

a. Insoection Scone ,

,

Boraflex degradation was first discussed in inspection re) ort 95-09

after the licensee identified elevated silica levels in t1e spent fuel

pool (SFP). Blackness testing, to verify the presence of a neutron

absorber, was performed during June 1996. The licensee received the

test results on September 3. 1996. The in.cpector reviewed the blackness

test results, the licensee's LER, the licensee's response to NRC Generic

Letter 96-04 "Boraflex Degradation on Spent Fuel Pool Racks." and the

licensee's license amendment submittal.

b. Observations and Findings

t

During 1995, the licensee identified elevated levels of silica in the

SFP which was an indicator of Boraflex degradation. Boraflex was

constructed of an organic polymer with a silica filler and neutron

i

absorbing boron carbide interspersed within the silica filler. Boraflex

degradation consisted of cracks and gaps forming in the Boraflex panels

with the Boraflex eventually becoming susceptible to dissolution in the

SFP water. The licensee took interim actions to limit the rate of

degradation, including not reducing silica levels in the SFP. The

i

licensee also established an administrative limit of greater than 1000

l parts per million (ppm) soluble boron in the SFP. The licensee

calculated the 1000 p)m boron would be adequate to maintain k,r, less

than 0.95 if all of t1e Boraflex was removed.

Blackness testing performed on approximately 300 storage cells during l

' June 1996, indicated three panels where Boraflex gaps exceeded 4 inches.

The design criticality analysis assumed any Boraflex gaps to be less

than 4 inches. TS 5.6.1.1 required the SFP racks to maintain k

! than or equal to 0.95 when flooded with unborated water. With he trrgaps,

less

the calculation that demonstrated TS compliance was invalid and the

licensee declared the SFP racks inoperable.

The licensee reviewed the acti;ns taken during the fall of 1995 when the

degradation was identified and determined the actions to be adequate

interim measures. The licensee originally planned to submit a TS

i amendment in early 1997 requesting approval to include soluble boron in

!

the criticality analysis. However, after discussions with the NRC, the

.

4 licensee accelerated the amendment submittal and submitted a license

amendment on November 12. 1996.

1

17

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_ . . _

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

!

.

.

l'

i

in addition to the amendment sabmittal, the licensee planned to arrange

'

the fuel in a checkerboard pattern in the SFP to ensure the SFP remained

subcritical with no Boraflex or soluble boron. Checkerboarding placed

fuel in the SFP such that either one or two cells out of every four

.

4

'

would be empty. A criticality analysis indicated that some - '

checkerboarding was required to demonstrate k,,,

would be less than 1.0

a with no Boraflex and flooded with unborated water.

'

- LER 96-014-00. " Failure to Comply with Design Basis Due to Degradation

.

of.Boraflex in Spent Fuel Racks." was reviewed by the inspector. With

j .

the addition of the accelerated license amendment submittal and the

1

planned checkerboarding, the inspector considered the LER appropriate.

i

The inspector verified the soluble boron limit was administratively

!

controlled and that the licensee had not been removing silica from the

SFP. The inspectors will continue to follow this issue through the

j licensee's LER supplement.

3

j c. Conclusions

A

j~

The inspector concluded that the licensee monitored the Boraflex

degradation and planned to submit a license amendment. However, the

license submittal was not being pursued in a timely manner until after

!

discussions with the NRC. Also, the decision to checkerboard the SFP

! was not made until after NRC discussions and a criticality analysis

indicated that the checkerboard must be performed to ensure the SFP

,

remained subcritical with unborated water.

'

j E2.2 Missina Scacers in Motor Control Center

i

i a. Insoection Scone

i

During refueling outage B2R06, the licensee noted that spacers were

removed from some Westinghouse motor control center (MCC) breaker

! buckets. The MCC spacers were. located between the bucket and the MCC

j

frame. The inspectors reviewed the licensee's corrective actions on the

,

1ssue.

1 b. Observations and Findings

4

i

Byron engineering contacted Westinghouse and were first told that the

j

spacers were shipping spacers and were not needed and that missing

spacers would pose no concern. Engineering continued to pursue the

t

issue with Westinghouse, who later determined that the spacers were

! installed in the original MCC seismic qualification testing.

The licensee 3erformed an interim o)erability assessment and determined

that the MCC Juckets were operable )ased on com)arisons of seismic

! testing performed at levels four times higher tlan Byron plant seismic

'

requirements. The inspectors reviewed and agreed with the assessment.

The licensee installed the spacers in the MCCs.

4

f

g 18

l

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

- _ . - . . --

..

c. Conclusions

Engineering aggressively pursued the MCC spacer issue with Westinghouse.

The operability assessment and corrective actions to install the spacers

was timely and thorough.

IV. Plant Sucoort

j R1 Radiological Protection and Chemistry Controls

.

R1.1 ALARA Concern .

a. Insoection Stone

During a routine tour of the auxiliary building, the inspectors

identified a worker lying in the Unit 1 positive displacement (PD)

charging pump (CV) room. The inspectors reviewed the licensee's

corrective actions and initial investigation results.

l b. Observations and Findings

On November 27, 1996, the inspectors identified a contracted engineer

l lying on the floor in the Unit 1 PD CV pump room. The dose rate where

the individual was lying was less than 1 mR/ hour. The worker was not

wearing a hard hat or safety glasses and had his feet propped up on the

pump skid piping. The inspector questioned the individual and was told

that he was a contracted engineer assigned instrument air system

walkdowns. In response to the inspectors ALARA concerns, the licensee

determined that the individual was in the auxiliary building for

a3 proximately 25 minutes and received no detectable radiation exposure.

T1e individual was relieved of his duties at the site.

c. Conclusions

The inspectors noted prompt management attention to this issue.

F1 Control of Fire Protection Activities

,

F1.1 Containment Sorav Pumo Room Fire Door Blocked Open (71750)

a. Insoection Scope

During a routine tour of the auxiliary building, the inspectors

identified a fire door between the Unit 2 CS pump rooms blocked open.

,

l

The inspectors reviewed the licensee's immediate corrective actions and

l initial investigation results.

b. Findinos and Observations

On October 7,1996, the inspectors identified that fire door D-846.

located between the 2A and 2B CS pump rooms, was impaired without a Fire

19  !

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l

l

l

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

(

- .

Barrier Impairment Permit (FBIP) on the door. Cables used to remotely

.

<

.. monitor RHR pump oil levels impaired the door. The inspectors notified

the operations department and the door was closed.

)

In response to the inspectors concern, the licensee determined that the i

door had a FBIP when the cables were installed: however, the FBIP was

issued for door repair due to an unrelated door hardware problem. The  !

1

l

mechanics installing the cables did not add the cables to the existing i

FBIP After the door was repaired, the FBIP was removed. At the end of

the inspection period, the licensee was deteruining the chronology of

events after the original FBIP was removed.

Byron Administrative Procedure (BAP) 1100-3, " Fire Protection Systems,

Fire Rated Assemblies, Ventila'lon Seals, and Flood Se'al Impairments "

Revision 10, stated, in part, tilat a FBIP was required for all fire

protection equipment, fire detection instrumentation, fire rate

i

assemblies, fire rated assemblies sealing devices, ventilation seals,

and flood seals which were impaired. Contrary to these requirements,

fire door D-846 was impaired without a FBIP initiated. The inspectors

considered this failure to follow procedures a violation of TS 6.8.1,

" Procedures and Programs" (50-455/96009-06(DRP)). -

l

'

4

c. Conclusions \

The inspectors concluded the blocked open CS fire door without a FBIP

indicated a need for additional improvement in procedure adherence when

)

impairing fire protection equipment. '

i

V. Manaaement Meetinas

X1 Exit Meeting Summary

l The inspectors presented the inspection results to members of licensee

management on November 14, 1996, and at the conclusion of the inspection on

December 17, 1996.

5

a

1 The inspectors asked the licensee whether any materials examined during the

inspection should be considered proprietary. No proprietary information

.

was identified.

l

,!

.

e

' 20

4

______ _ __ __ _ _ _

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

!

.

PARTIAL LIST OF PERSONS CONTACTED

, licensee

K. Kofron, Station Manager

D. Wozniak, Site Engineering Manager

T. Gierich, Operations Manager

P. Johnson, Technical Service Superintendent

E. Campbell, Maintenance Superintendent

M. Snow Work Control Superintendent

D. Brindle, Regulatory Assurance Supervisor

K. Passmore, Station Support & Engineering Supervisor

J. Feimster Site Engineering Mechanical Lead

M. Robinson, System Engineer

P. Donavin, Site Engineering Mod Design Supervisor

T. Schuster, Site Quality Verification Director

R. Colglazier, NRC Coordinator ,

'

B. Gossman, Chemistry Supervisor

S. Gackstetter, Thermal Group Leader

W. Walter. 0]erations Engineer Unit 0

R. Wegner, S1ift Operations Supervisor

W. Kouba, Long Range Work Control Superintendent

i

INSPECTION PROCEDURES USED

IP 37551: Onsite Engineering

IP 61726: e

Surveillance Observations l

IP 62703: Maintenance Observations '

IP 71707: Plant Operations

IP 71750: Plant Support Activities

IP 92901: Followup - Plant Operations

IP 92902: Followup - Maintenance

21

j

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J

.

ITEMS OPENED. CLOSED, Af40 DISCUSSED

~

Opened

i

EE: 454/455/96009-01 V10 Failure to have sufficient quantitative

acceptance criteria in procedure OBVS SX-5.

eel 454/455/96009-02 V10 Failure to use adequate test instrumentation to  ;

measure the amount of silt in the SX cooling {

tower basins. '

EEI 454/455/96009-03A VIO Failure to take appropriate corrective action

for previous silt accumulation in the SX cool,ing I

tower basins. ,

EEI 454/455/96009-03B VIO Failure to take prompt corrective action to

repair degraded SX cooling tewer basin trash

racks.

EEI 454/455/96009-04 VIO Failure to have adequate design control measures

in place to ensure that the design-basis of the

SX system was correctly translated into

specifications.

eel 454/455/96009-05 VIO Failure to update the UFSAR.

50-454/455/96009-06 VID Failure to follow procedure BAP 1100-3 regarding

fire door impairment.

Closed

50-454/94022-02 VIO Inadequate procedures

50-454/95003-03 IFI Diesel generator hairline cracks on air l

intake manifolds were identified during a

monthly surveillance.

50-454/96003-03 IFI Potential effects of boric acid corrosion on

the carbon steel filtered vent system.

50-454/96007-02 IFI CS pump room 1A contaminated due to floor

drain plugging.

22

.,

LIST OF ACRONYMS USED

.

ALARA As Low As Reasonably Achievable

ASME American Society of Mechanical Engineers

BAP Byron Administrative Procedure .

BOS Byron Operating Procedure

BVS Byron Surveillance Procedure

CS Containment Spray

FBIP Fire Barrier Impairment Permit

MCC Motor Control Center

mR millirem

_ 00S Out of Service

RH Residual Heat Removal System

RSH River Screen House

SAT Station Auxiliary Transformer

SFP Spent Fuel Pool

SG Steam Generator

SI Safety Injection

SSPS Solid State Protection System

SX Essential Service Water

SXCT Essential Service Water Cooling Tower

TS Technical Specification

UFSAR Updated Final Safety Analysis Report

UHS Ultimate Heat Sink

VF Filtered Vent System

23