ML20153D305

Insp Rept 50-293/88-23 on 880620-30.No Violations Noted. Major Areas Inspected:Licensee Corrective Actions in Response to NRC Info Notices86-003 & 053 Re Limitorque Valves & Raychem Heat Shrink Tubing,Respectively

ML20153D305
Person / Time
Site:	Pilgrim
Issue date:	08/23/1988
From:	Thomas Koshy NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20153D303	List: ML20153D300 ML20153D305
References
50-293-88-23, IEIN-86-003, IEIN-86-053, IEIN-86-3, IEIN-86-53, NUDOCS 8809020163
Download: ML20153D305 (15)

See also: IR 05000293/1988023

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U.S. NUCLEAR REGULATORY COMMISSION

REGION I

. Report No. 50-293/88-23

Cocket No. 50-293

License No. DPR-35 ,

Licensee: Boston Edison Company

800 Boylston Street

Boston. Massachusetts 02199

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Facility Name: Pilgrim Nuclear Power Station. Unit 1

Inspection At: Braintree and Plymouth. Massachusetts

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Inspection Cunducted: June 20-30, 1988

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Inspectors: b~O'N

T. Koshy, Lead Reactor Engineer date

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fot J. F. Lara~ R ctor Engineer date

Approved by: 9 3 It'

i C. J.VAnderson, Chief, Plant Systems Section date

Inspection Summary: Thir. vas an announced inspection to review the licensee

corrective actions in response to Information Notice 86-03 regarding the

! unqualified internal wiring in Limitorque valves and Informstion Notice

! No. 86-53 which addressed the improper installation of Raychem Heat Shrink

i tubing. This inspection also looked at some electrical open items. ,

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Results: The licensee corrective action to address the qualifications of

i limitorque internal wiring was insufficient in that the inspectors observed

three unidentifiable wires in valves located inside the containment. See

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. Section 4 for details. The licensee developed additional test data for

supporting the qualification of Raychem Heat Shrink Tubing installations.

Section 6 of this report documents the licensee response to previously

identified violations and unresolved items.

! The presence of unidentifiable wires in the environmentally qualified motor

' operated valves indicate a weakness in maintenance and quality control

activities.

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DETAILS

1.0 Persons Contacted

1.1 Boston Edison Company (BECo)

• M. Andrews, Sr. QC Engineer

J. Coughlin, Principal Electrical Engineer

S. Das, Sr. Electrical Engineer

S. Dasgupta, I&C Division Manager

N. Eisenmann, Sp. I&C Engineer

R. Fairbank, Design Section Manager

• F. Famular, QA Manager

D. W. Gerlits, Safety and Systems Analysis Engineer

"R. R. Grammont, Maintenance

• R. E. Grazio, Regulatory Affairs Section Manager

• P. Hamilton, Compliance Division Manager

• K. L. Highfill, Station Director

E. J. Janus, Sr. Electrical Engineer, Nuclear Engineering Department

R. L. Kirven, Electrical Engineering Supervisor, Nuclear

Engineering Department

• F. J. Mogolesko, Environmental Qualification Proj et Manager

• A. V. Mori:1, Acting Planning and Outage Depa:tme t Manager

K. T. O'Donnell, Electrical Maintenance Engineer

J. Pawlak, Principal Electrical Engineer, Nuclear Engineering

Department

L. Perfetti, Electrical Engineer, Nuclear Engineering Department

• J. E. Peters, Electrical Division Manager

B. Rancourt, Sr. I&C Engineer

• J. A. Seery, Technical Section Manager

R. N. Swanson, Nuclear Engineering Manager

T. Tracy, Civil Structure Division Manager

• T. A. Venkataraman, Sr. QA Engineer

• R. Whetsel, Sr. Compliance Engineer

V. Zukauskas, Principal Structural Engineer

1.2 U.S. Nuclear Regulatory Commission (NRC)

T. J. Kim, Resident Inspector

J. J. Lyash, Resident Inspector

C. Warren, Senior Resident Inspector

• Present at the exit meeting on June 30, 1988.

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2.0 Purpose

The purpose of the inspection was to review the following items.

• ihe environmental qualification of internal wiring utilized in the

Limitorque motor operated valves (MOVs) that are required to perform

safety functions in a harsh environment.

• The installation of Raychem heat shrinkable tubing on safety related

cable splices.

• Electrical and Equipment Qualification open items.

3.0 Background

On September 30, 1985 Commonwealth Edison reported to the NRC that it

discovered four Limitorque operators with jumper wires different from

those tested by Limitorque in their environmental qualification program.

Subsequent to this finding, several licensees identified similar problems.

That led to the issuance of Information Notice No. 86-03 which promulgated

the need for establishing the qualification of Limitorque internal wiring.

On May 14, 1986 the licensee for Davis Besse plant reported that termina-

tions and splices using heat shrinkable tubing were not done according to

the manufacturer's instructions in that the installed configuration placed

the plant in an unanalyzed condition. Typical discrepancies included

improper diams'.cr of the tubing and, improper overlap of the heat shrink-

able tubing (HST). Discrepancies of this nature were observed at various

plants. As a result NRC issued Information Notice No. 86-53,

4.0 Limitorque MOV Wiring (TI 2515/75)

The licensee inspected all MOVs covered under the EQ program to determine

if the internal wiring was environmentally qualified. The licensee docu-

ment PDC 84-60 addressed the inspection and upgrade of the MOV wiring.

The inspectors reviewed the checklist and the work instructions contained

in the above docunent. The document identified the acceptable wires and

also several other aspects of limitorque MOVs which are critical for main-

taining the equipment qualification. The team selected the following

seven, from a total of seventy MOVs covered in the environmental qualifi-

cation (EQ) program. The first two MOVs were selected from the valves

inside containment.

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MO-202-5A

MO-202-58

MO-1001-28A

MO-1001-43A

M0-1001-43C

M0-2301-10

MO-2301-33

All but two valves contained identifiable Rockbestos SIS or General Electric

Vulker.e Supreme wires. Valves MO-202-5A and MO-202-5B contained wires

which could not be identified. The inspectors noticed a red jumper wire

on the terminal block inside the Limitorque compartment of M0-202-5A. It

was the only red wire and it did not have any identifiable markings on it.

The licensee presented a QC Verification Checklist dated November 2, 1984.

It refers to the following documents which trace the wire to be Gauge 12

SIS GE Vulkene.

• E-928 Material Receiving Instruction dated June 7, 1934

• 82-027.1 Material Receiving Report for Purchase Order FN-4050Q

dated September 18, 1984

+ General Electric Certificate of Compliance dated February 14, 1985

for Customer Order FN-4050Q

In MOV MO-202-5B the inspectors observed two types of unidentifiable wires

inside the Limitorque compartment. One was a grey wire with a red line

used as a jumper on the terminal block, the other was a white wire con-

nected between the limit switches. The licensee presented the following

document to establish the origin of the wire.

+ 84-060-04-E-002 QC Verification Checklist dated November 2,1984

However, this document traced the wire to be a GE Vulkene Supreme red

wire. The field installation was a grey wire with a red line on it.

This raised some questions regarding the adequacy of QC inspection. The

licensee generated PCAQ NED 88-035 to address this concern. The licensee

believes that the white wires on the limit switches were installed by the

manufacturer, Limitorque. The licensee initiated a 10 CFR Part 21 review

to address the extent of the problem and to evaluate this issue for

reportability to the NRC.

The licensee had replaced several MOV assemblies under PDC 84-16 in the

current plant outage. Only a few of those new assemblies were inspected

for Environmental Qualification requirements, as there were no discrepan-

cies identified in the first batch inspected. In the light of the

concerns identified during this inspection, the licensee committed to

complete the walkdown of all new POVs for any potential EQ concerns,

before restart.

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Subsequent to the inspection, the licensee inspection revealed a few more

instances of unqualified wiring in MOVs. The licensee review concluded

that some of the wires are qua11fiable. The presence of unidentifiable

wiring in the MOVs that are covered under the EQ program is an unresolved

item pending the licensee evaluation of the causes of the discrepancy and

the corrective action. (50-293/88-23-01)

5.0 Raychem Heat Shrinkable Tubing Installation (TI2500/17)

In response to the NRC Information Notice 86-53, Improper Installation of

Heat Shrinkable Tubing, the licensee issued a "Potential Condition Adverse

to Quality Report." This report contained a preliminary evaluation that

recognized some concerns on the subject installations at Pilgrim Station.

PNPS conducted a field inspection of a sample of installations in order

to document the most limiting configurations to be addressed. The sample

size chosen was equal to or greater than that specified in standard,

Sampling Procedures and Tables for Inspection By Attributes MIL-ST0-1050.

The selected samples were inspected to document acceptable configurations

that can be tested to establish qualification. The test samples were then

made with a bend to crease and were subjected to equipment qualification

tests. This test establishes qualification of Raychem splices with h"

real length for Gauge 14 and 16 cable sizes. The other cable sizes were

tested with a one inch seal length.

Based on the licensee's acceptance criteria as supported by the qualifica-

tion data, the NRC inspectors reviewed the following selected installations.

Safety Related Penetration Q106B (approximately 20 power and control

splices)

• MO-202-5A MOV

• MO-1001-63 MOV

• J208 Junction Box

+ J456 Standby Gas treatment splice box

• J177 Standby Gas treatment splice box

+ 10-DPIS-261-12C Pressure Switch for Low Pressure Injection

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2-PS-1001-104A Pressure Switch

• 2-PS-1001-93A Pressure Switch

The NRC inspectors walked down the above installations for the following

attributes.

• Seal length of h inch to 1 inch per the licensee qualification data

• Use of proper size HST

• improper or inadequate shrinking of HST

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Use of HST over unqualified surfaces such as braided jackets

• Appropriate use of shims

Based on the records verified and the samples inspected, no discrepancies

were observed. The licensee has developed Procedure No. 3.M.3-17.1

"Field splice, Repair, and Sealing of Safety Related Cables (1000V and

Under) Raychem WCSF-N Sleeve NPK, NPKV, NMCK, NCBK and NESK kits

Installation". The inspectors reviewed this procedure for the inclusion

of the manufacturer's requirements.

No violations or deviations were identified.

6.0 Status of Previcusly Identified Items

6.1 .(Update) Violation (88-08-01) Failure to Perform Periodic

Calibration / Testing of DC Circuit Breakers: This violation pertains

to the failure of the licensee to perform periodic calibration / testing

of DC circuit breakers as required by PNPS Technical Specification

6.8A. Periodic testing of these Class 1E breakers is specified to

ensure that they will perform their safety function when called upon.

The inspector reviewed BECo Nuclear Engineering Department's (NED)

analysis addressing the untested breakers. The Pilgrim Unit 1 Report

88XE-1ER-Q, "Analysis of 125V and 250V DC System Molded Case Circuit

Breaker Maintenance and Testing" documented the analysis and methodology

used to develop a testing program for a representative sample of all

types of safety-related DC breakers installed at PNPS. Testing

includes breakers of varying ratings and types. A sample of 44 breakers

will be tested. The inspector verified that all types of breakers

were considered for testing and reviewed NED's method of choosing the

sample to be tested.

The inspector reviewed in detail the technical analysis and basis

used to document the breaker testing program. Independent

calculations revealed no discrepancies in the NED acceptance

criteria with respect to the guidelines presented in NEMA Standard

AB 2-1984, "Procedures for Field Inspection and Performance

Verification of Molded Case Circuit Breakers Used in Commercial and

Industrial Applications".

The breaker acceptance criteria was incorporated into PNPS procedure

8.Q.3-4, "125/250 VDC Motor Control Center Testing and Maintenance",

Revision 5. The procedure provides maintenance personnel with

requirem...ts for periodic testing and maintenance of 125/250 VDC

Motor Control Centers.

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Upon conclusion of this inspection period, the licensee had completed

testing 23 of the 44 DC breakers. The remaining breakers not yet

tested are being tracked and scheduled for completion prior to

restart. Upon completion, NED will review the results to evaluate

breaker performance. If all the breakers pass the acceptance

criteria, long-term testing will be scheduled for the entire popula-

tion of Class IE DC; breakers. However, if any type of the breakers

fail the criteria, all breakers of that type in the entire population

will be tested before restart.

Test results and analyses will be provided to the NRC for review

prior to restart. The licensee has committed to develop and

implement a long-term DC breaker surveillance testing program. The

program will include the type and frequency of testing to be performed.

The licensee comnitted to implement this program by October 1,1988.

Pending NRC review of the test results, this issue will remain open.

6.2 (Closed) Violation (88-08-02) Inadequate Battery Maintenance: During

a previous special team inspection of the electrical power systems.

NRC inspectors identified examples of inadequate battery maintenance

and procedures. Examples of corrosion by products were observed on

various battery terminals of the 125 VOC Control and 250 VDC power

batteries. Licensee procedures did not include criteria for removal

of corrosion by products, spacing between battery cells and seismic

support racks, and verifying the torquing of battery connections.

The NRC inspector reviewed the licensee's response to the notice of

violation during this inspection. The review revealed a revision of

the following procedures:

• 8.C.14, "Weekly Pilot Cell, Overall Battery Check and Battery

Charger Test", Revision 23

• 8.C.16, "Quarterly Battery Cell Surveillance", Revision 15

These procedures include battery surveillance criteria and

requirements of PNPS Technical Specification sections 4.9.A.2.a and

4.9.A.2.b. These sections specify the weekly and quarterly battery

surveillance requirements.

Requirements for the inspection of corrosion by products on battery

terminals, battery cells and seismic support racks spacing, and

verification of proper terminal torque values are now incorporated

into a newly issued PNPS Plant Maintenance Procedure 3.M.3-25.1,

"Periodic Battery Inspections", Revision 0.

The inspectors inspected three battery banks for cleanliness and proper

maintenance. Three separate cell terminals exibited varying degrees

cf corrosion on battery "B" (02). Review of the licensee's Maintenance

Request (MR) log book indicated that several MRs were written to

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specifically clean the identified battery cell terminals which showed

sign of corrosion by-products. Inade,uate cleaning and inspection

for the past several years has made all the battery terminals very

susceptive to corrosion. The inspector concluded that the issued MRs

provided only temporary and not long-term solution to the problem of

corrosion by products. This lack of maintenance for all battery

cells could in the long run cause insufficient charging due to poor

terminal contact. The licensee agreed with the inspector that unless

all battery terminals and bolted connections were completely cleaned

and adequately maintained at the same time, corrosion by products

would be a recurring problem. The licensee committed to completely

clean and apply the protective wax on all battery banks prior to

restart.

Based on these actions, this violation is censidered closed.

6.3 (Closed) Unresolved * Item (88-03-05) Low Setpoints of Degraded Grid

Voltage Relays: This item pertains to degraded grid voltage relay

setpoints being set too low to ensure minimum required voltages at

safety-related loads during a degraded grid scenario. On January 30,

1988 the licensee reported to the NRC that the degraded grid voltage

protection system setpoints were set too low. The licensee committed

to complete a detailed review analysis of the Electrical Distribution

System to address low relay setpoints and recommend corrective

action.

BECo's Nuclear Engineering Department (NED) performed the review

analysis of the Electrical Distribution System. NED's Power Systems

Group Study on load flow and voltage conditions of PNPS Auxiliary

Power Distribution System resulted in various modifications within

the electrical systems. The study included new alarm and trip

setpoints for the degraded grid voltage protection system. Based on

these setpoints, the minimum acceptable switchyard voltage had to be

revised. In addition, to reduce voltage drops within the distribu-

tion system under LOCA conditions, certain loads will be shed from

the safety bus. To further assure proper voltage levels at loads,

RHR and CS pump starting logic will be modified to add a time delay

before any automatic start. Additional alarms will also be installed

to provide operators with additional information on the status of

load shed relays. Within the scope of,the study results, specific

non-safety loads will be relocated from safety busses to non-safety

busses. Results of the NED study indicate that these modifications

will provide greater assurance that all safety-related equipment will

have adequate voltage for proper and safe operation during all modes

of operation.

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During this inspection period, the NRC inspectors held various

discussions with NED staff members. An in-depth review of NED's

voltage study was performed. Modifications resulting from the study

are documenied in PDC 88-07. Results of the study, scope of

modifications, and inspector observations are described below.

A. Degraded Grid Protection Setpoints for Alarm and Trip Relays:

PNPS is connected to the New England power grid through a 345

KV ring bus. Rhode Island Eastern Massachusetts Vermont Energy

Control (REMVEC) monitors and assures that PNPS receives

adequtte power to be distributed throughout the station.

REMVEC presently has procedures in place to provide a minimum

of 330 KV at the PNPS switchyard. Results of the group study

on load flow and voltage conditions revealed that the present

330 KV minimum required grid voltage would not ensure adequate

voltage for all safety-related loads under all operating

conditions. Therefore, BECo has requested REMVEC to revise

their operating procedures to provide a minimum of 340 KV to

PNPS. REMVEC will notify PNPS if the new minimum accaa+Qle

voltage cannot be maintained and thus allow PNPS to prepare for

necessary actions.

Based on the new minimum acceptable switchyard voltage,

modifications were made to the degraded voltage alarm and trip

relay setpoints. New relays are being installed to support the

voltage range required by the new setpoints. These new relays,

ITE-27N Undervoltage Relay, have higher accuracy and response

characteristics. Accordingly, trip relays now have a trip

setpoint of 3868V, as opposed to the previous setpoint of

3745V. Alarm relays are now set at 3959V, as opposed to the

previous setpoint 3850V. These setpoints are applicable to

both Class IE 4.1GKV busses A5 and A6.

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The new trip setpoints correspond to an MCC voltage of 437V at

MCC busses B14 or BIS under worst case conditions. This ,

condition results in a margin of 7V above the minimum required

MCC voltage of 430V. However, it should be noted that the

worst case MCC voltage of 437V ocurrs at a switchyard voltage i

of 337KV which is below the minimum acceptable voltage of

340 KV. All other MCCs have a greater voltage margin.

The inspector reviewed BEco calculations PS-67 and PS-68 which

provide the analysis performed to determine the new trip and

alarm setpoints. No deficiencies were identified.

B. Modification of Emergency Diesel Generator Lead Shedding logic:

This modification initiates load shedding under LOCA conditions

coincident with the safety related busses being supplied by the

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Startup Transformer. However, the load shedding logic will be l

initiated only if the 4.16KV bus voltage is at or below the '

alarm relay setpoint of 3959V for a duration greater than the

time delay of 9.2 seconds. Loads to be stripped from the bus

are only those loads which are not required to mitigate the '

consequences of an accident. These load shedding logic changes

ensure that, when in any degraded voltage condition, sufficient

voltage is available to all safety-related loads.

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Other logic modifications include the removal of the Feedwater

Pump auxiliary oil pumps from the load shedding logic. These

pumps will not be stripped from the 4.16KV busses. This will ,

allow the plant operator to restart the pumps if needed.

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C. Modification of RHR and CS Pump Starting Logic: This modifica-  !

tion ensures that, under LOCA conditions, adequate power is i

available for all required equipment and loads during load '

starting transients. Pump starting logic for RHR and CS pumps

will be modified so that for any automatic pump start, time .

delays will be imposed when safety busses are being supplied by l

the startup transformer. The time delay is the same that exists  !

when the emergency diesel generator or the shutdown transformer  ;

are supplying the Class 1E 4.16KV busses. Specifically, CS

pumps will have a 1/3 second delay for any automatic start. RHR

pumps A and B will have a 5 second delay while RHR pumps C and D  :

will have a 10 second delay for any automatic start.

D. Additional load Shedding Alarms: This modification provides i

the operator with additional alarms regarding the status of load [

shedding relays. Once a LOCA signal is received, alarms alert ,

the operator that load shedding has been initiated. Presently,  ;

once the LOCA signal is cleared, these alarms are also cleared.  :

This situation can lead the operator to believe that all load '

shedding relays are reset and thereby loads can be restarted if

needed. However, there are some loads which require manual }

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resetting of their respective load shedding relays. This modi- !

fication provides for the installation of additional alarms to  ;

alert the operator that certain loads are still shed and require [

manual resetting of their respective relays, i

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E. Relocation of non-safety loads from safety-busses: This modift-

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cation, as documented in PDC 88-18, consists of relocating five ,

non-safety loads from safety busses B14 and BIS to non-safety  ;

busses B13 and B19B. The loads include plant heating pumps and [

auxiliary boilers and their associated equipment. Relocating j

these loads reduces power requirements at the safety busses and -

thereby improves voltage during all modes of operation.

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NED analysis to determine relay setpoints was performed with the aid

of a commercial software program called Distribution Analysis for

Power Planning, Evaluations and Reporting (DAPPER). Results of

NED's DAPPER generated calculations were cross-referenced with those

of Stone & Webster's similar main frame program. Numerical

results were found to be essentially identical.

During this inspection, the NRC inspector performed an in-depth

review of various licensee documents pertaining to proposed degraded

grid protection system design changes. These documents were

reviewed independently and later discussed with NED staff members.

Documents reviewed are listed in Attachment 1. New relay voltage

ranges and tolerances were reviewed to verify they supported the

voltage study requirements.

BECo is in the process of submitting proposed Technical Specification

changes to NRR for review and approval. Technical Specification

changes incorporate the design modifications resulting from the load

analysis and voltage study.

Based on the information presented to the NRC inspector, this

unresolved item is considered closed.

6.4 { Closed) Unresolved Item (86-40-01) Raychem Splices on ECCS

Equipment: This item pertains to the motor lead splices performed by

General Electric on 5 Kilovolts (KV) motor. During January 1987 the

motor lead splices for these pumps were removed to facilitate 10 CFR

50 Appendix R, modifications. During this removal, it was discovered

that B and D RHR pump motor splices were improperly installed, some

cable insulation damaged and some strands severed.

The licensee initiated an extensive program to reinspect the SKV

splices. The problem was traced to a certain crew that performed the

splices. The licensee elected to replace the potentially affected

splices with a qualified splice using procedure No. 313 "5KV Cable

Splice Replacement" Revision 2. The unqualified splices remained in

service only for a short duration when the plant was shutdown. The

inspectors reviewed the following documents to verify the adequacy of

the corrective action.

• Root cause and corrective action plan 86-192

• Failure and Malfunction Report 86-435

• Maintenance Request 86-10-53

The damaged cable was evaluated by General Electric Company and the

recommended corrective actions were taken by the licensee. The

licensee has taken measures to increase QC attention on contractor

performed services. This item is closed,

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6.5 (Closed) Unresolved item (50-293/88-08-04) Solid Fuse Links: This

item pertains to the use of solid links instead of fuses in the auto

trip circuit of the 4160 volt breakers and the Emergency diesel

generator field flashing circuits.

The licensee has elected to use solid links in the auto trip circuit

of the 4160 breaker to provide the maximum tripping capability. This

circuit carries the current to operate the trip device only and does

not carry the fault current. The trip signal from the protection

system is generated through remote sensing relays. Moreover, any

potential fault on this circuit will be interrupted by a magnetic

only circuit breaker. The tripping of this breaker can cause power

failure only to one bus that belongs to one train.

The field flashing current is limited to approximately 60% of the no

load generator field current. A 2.5 chm resistor limits this

current to approximately 50 amperes and is immediately removed when

the field is established. Since this circuit is current limiting

and critical for field flashing, the fuse would function to provide

only short circuit protection. For greater reliability in

establishing the field in the exciter, a solid link is used. The

use of a solid link provides an electrically continuous circuit to

function without interruption or failure. Short circuit protection

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for the entire circuit is still provided by the circuit breaker at

the distribution panel. The consequences of tripping this circuit

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breaker, resulting from a short circuit, would be a loss of diesel

generator control power to an already inoperable generator due to a

failed field flashing circuit. Since each diesel generator is

supplied from an electrically and physically independent DC power

supply, the tripping of the field flashing circuit breaker will not

affect the operability of the second diesel generator.

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This item is closed.

6.6 (Closed) Inspector Followup Item (87-53-05 Item #2)

Analog Trip System Fuses: This item deals with the blown fuses in

the analog trip system during the loss of offsite power event on

November 12, 1987.

The licensee investigation discovered that four fuses were blown in

the analog trip system (ATI). The failures were in the power supplies

of the ATI System. The root cause of the problem is attributed to

high inrush current due to repeated energizing and denergizing. The

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inspector reviewed the trip characteristics of the original fuse

FNM KTKR, the fuse supplied by the manufacturer. The licensee

replaced this fuse with an MIN type which is very similar to the

original fuse. Due to the similarity in characteristics the

inspector, agreed with the licensee that the failure could have

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happened even with the use of the original fuse. In order to prevent

similar fuse failures, BECo has installed a new type of fuse, FNM

which provides additional margin to accommodate switching transients.

The licensee review of other instrumentation fuses did not reveal any

new concerns.

This item is closed.

6.7 (Closed) Violation (87-32-0_1) Equipment Qualification Environmentg

P_rofile in Containment: This pertains to the accident environment

profile utilized by the licensee for qualifying safety related equip-

ment located inside the drywell. The qualification requirements for

this equipment is addressed in 10 CFR 50.49. As required by this

regulation, the licensee did not use the most limiting design basis

time dependent temperature profile to qualify the safety related

solenoid valve SV-220-44 and cable splice assemblies Q102A, Q102B,

Q103A and Q1038. The licensee instead, qualified the equipment to a

large break temperature profile which was 30'F lower than the

temperature profile for a small break LOCA.

In response to this violation, the licensee developed a composite

imperature profile for the drywell environment. This information

.as submitted to the NRC for review and is currently being reviewed

'y the office of the Nuclear Reactor Regulation. The profile indicates

s peak temperature of 320'F in the initial part of the accident. The

licensee stated that all of the equipment was qualified based on the

documented test reports which the licensee had in possession before

November 30, 1985.

The inspectors reviewed the qualification basis of terminal blocks

used inside Limitorque compartments. The terminal blocks were

originally qualified as per test report No. B0119 which tested the

terminal blocks for a peak temperature of 311*F. Limitorque test

report B-0027 dated August 31, 1978 provides data on the ambient

temperature of terminal blocks when the actuator is subjected to

high superheat conditions. This test establishes that the internal

component temperature for terminal block does not exceed the saturated

steam temperature for the required operating duration. Based on this

fact, the qualification of the terminal block is established through

test report B0119 for terminal blocks utilized in power and control

applications.

The inspectors also reviewed the licensee records on revising the

qualification data for other drywell instrumentation, cables, penetra-

tion and splices. No discrepancies were identified.

This item is closed.

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14

7.0 Unresolved Items

Unresolved items are matters for which more information is required in

order to ascertain whether they are acceptable, violations, or deviations.

One unresolved item is discussed in Section 4 of this report.

8.0 Exit. Interview

At the conclusion of the inspection on June 30, 1988, the inspectors

met with the licensee representatives denoted in Section 1.0. The

inspectors summarized the scope and findings of the inspection at that

time.

No written material was provided to the licensee by the inspectors.

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ATTACHMENT 1

DOCUMENTS REVIEWE0

1) Licensee Event report 88-003-000, "Low Setpoints of Degraded Grid Voltage

Relays due to Error in Model Used for Analysis," January 30, 1988.

2) Failure and Malfunction Report 88-29, January 30, 1988.

3) Plant Design Change (PDC) 88-10.

4) Scope and Justificaticn Approval 88-10. "Replace Degraded Voltage Relays

and Modify Load Shedding Logic," February 4,1988.

5) Field Revision Notice (FRN) 88-07-01.

6) BEco Calculations:

a) PS-67; Degraded voltage - trip setpoint, June 21, 1988

b) PS-68; Degraded voltage - alarm setpoint, June 21, 1988

7) Safety Evaluations:

a) 2277; Replacement of voltage relays and modification of load

shed logic

b) 2289; Technical Specification changes evaluation

c) 2290; Post FRN 88-07-01 evaluation.