ML20080J184

Evaluation of Utility Response to Suppl 1 to NRC Bulletin 90-01:South Texas-1/2

ML20080J184
Person / Time
Site:	South Texas
Issue date:	02/28/1995
From:	Udy A External (Affiliation Not Assigned), IDAHO NATIONAL ENGINEERING & ENVIRONMENTAL LABORATORY
To:	NRC
Shared Package
ML20080J186	List: ML20080J184
References
CON-FIN-L-1695 IEB-90-001, IEB-90-1, INEL-95-0082, INEL-95-82, TAC-M85444, TAC-M85445, NUDOCS 9502270152
Download: ML20080J184 (19)

Text

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INEL-95/OO82 i

February 1995 1

Idaho \

National l Engineering Evaluation of Utility Response to j

'"##'"##'Y Supplement 1 to NRC Bulletin 90-01:

South Texas-1/-2 j

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1 Alan C. Udy ,

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' TECHNICAL EVALUATION REPORT- t k ,, i G

, . . - Evaluation of Utility Response to Supplement,1 to. .;

g NRC Bulletin 90-01:: South Texas-1/-2  !

' Docket Nos. 50-498.and~50-499-q 1;

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Alan C. Udy 4 i

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National Nuclear Operations Analysis Department 2  !

Lockheed Idaho Technologies Company: .

Idaho National Engineering Laboratory

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Prepared for the:

U.S. Nuclear Regulatory Commission

. - 1 Washington, D.C. 20555' "and for the U.S. Department of Energy.

Under DDE-Idaho Operations Office  !

Contract DE-AC07-941D13223 FIN No. Ll695, Task No. Ila ,

TAC Nos. M85444 and M85445 i

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p This report. documents the Lockheed Idaho Technologies Company review of -1 the South Texas Project, Unit Nos.' I and 2,.submittals that respond to  :;

Supplement I to NRC Bulletin 90-01. This NRC-Bulletin provides information' 5 regarding the loss of_ fill-oil _ in.certain pressure and differential pressure.

- transmitters manufactured.by Rosemount, Inc. This report identifies areas of  :

non-conformance to the requested actions and the reporting requirements. ,

Exceptions to the requested actions and the reporting requirements are-  !

evaluated.

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FIN No. L1695, Task No. 11a ;l B&R No. 320-19-15-05-0 l Docket Nos. 50-498 and 50-499 l TAC Nos. M85444 and M85445 l i

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i PREFACE.

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This report is ' supplied-'as part of the " Technical Assistance in' Support.-

.of the Instrumentation and Controls Systems Branch."-.It'is being conducted

.for the U.S. Nuclear Regulatory Commission, Office of Nuclear Reactor .

Regulation, Division of: Reactor Controls and Human Factors,. by Lockheed Idaho Technologies Company, National Nuclear Operations ~ Analysis Department. ,.

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1 CONTENTS. i r

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SUMMARY

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i PREFACE ................................................................. iii

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1. INTRODUCTION ...................................................... I

2. NRC SPECIFIED REQUESTED ACTIONS ................................... <4 -

3. EVALUATION ........................................................ 7 3.1 . Evaluation of Licensee Response to Reporting Requirements ... 7 3.2 Evaluation of Licensee Response to Requested Actions ........ 7

4. CONCLUSIONS ....................................................... 13

5. REFERENCES'........................................................ 14 r

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Evaluation of Utility Resnonse to Sunnlement-1 to s

• 3_; _ NRC Bulletin 90-01r South Texas-1/-2 '

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'1. INTRODUCTION-

-The'NRC: issued Bulletin 90-01'on March 9, 1990 (

Reference:

1). Th'at' M . Bulletin discussed certain Rosemount pressure and' differential pressure ~. j 4

transmitter models' identified by the manufacturer as. prone to fill-oil -

1 4 , . leakage. The bulletin rq uested licensees to identify.whether these.

N .; transmitters were or may later be installed in safety-related systems.  ;

- T  : Actions were ' detailed for' licensee implementation for identified transmitters -

y presently installed in a' safety-related system. These same actions; apply'to' -

j identified transmitters presently held in inventory for later installation in.

, .a safety-related system.-  ;

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.i With the gradual leakage of fill-oil, the transmitter would not have the l long term accuracy, time response, and reliability needed for its intended; {

safety function. Further, this condition could go undetected over a long.  ;

. period. Re'dundant instrument channels are subject to the same-degradation: '

mechanism. This increases the potential for a common mode failure. - Thus,  ;

- this potential failure mechanism raised concern for the reliability of reactor-protection systems (RPS),' engineered safety features (ESF) actuation systems, ,

.and anticipated transie'nt without scram (ATWS) mitigating systems. 'To achievei l high functional reliability, there must be a low probability.of component ,

failure while operating, with any failures readily detectable.- l t

Supplement I to NRC Bu11etin'90-01 (Reference 2) was issued on December 22, 1992. The Supplement informed licensees of NRC staff activities i regarding the subject transmitters, and noted continuing reports of transmitter failures. . The NRC requested licensee. action to resolve the issue.  ;)

LThe Supplement also updated the information contained in the original l

bulletin. The licentee was requested to review the information'and determine H if it was applicable at their facility. Further, the itcensee was requested' h

to modify their actions and enhanced surveillance monitoring programs to -l conform with the direction given. Finally, the licensee was instructed to r

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I respond to the NRC. The Requested Actions in Supplement I to NRC_ Bulletin 90-

- Ol' supersede the original NRC Bulletin 90-01 Requested Actions.

In responding to Supplement I to NRC Bulletin 90-01, the licensee is  ;

directed to address three items.

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1. A. statement either committing the licensee to take:the NRC Bulletin 90-01, Supplement 1, Requested Actions-or taking ,

exception to those actions.

2. Addressing the actions committed to in-the above statement, provide:

a. a list of the specific actions, including any justifications, to be taken to complete the commitment,  ;

b. a schedule for completion, and

c. after completion, a statement confirming the actions committed to are complete.

3. A statement identifying the NRC Bulletin 90-01, Supplement 1, Requested Actions not taken, along with an evaluation providing the basis for exemption.

In implementing the replacement option of the NRC Requested Actions, ,

plant shutdown exclusively for replacing the transmitters is not required.

This allowance infers that replacements can be scheduled. With replacement in a timely manner, enhanced surveillance monitoring for interim operation is not required.  ;

The Houston Lighting and Power Company, the licensee for the South Texas Project, Unit Nos. I and 2, responded to Supplement 1 of NRC Bulletin 90-01'  ;

with a letter dated March 4,1993 (Reference 3). The licensee provideo l additional information and clarification in letters dated September 29, 1993 (Reference 4), and January 31, 1995 (Reference 5). This technical evaluation 1 report evaluates the completeness of those submittals. It also determines l

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whether proposed surveillance methods are adequate to determine fill-oil loss-caused degradation of the transmitter. Finally, this report addresses the l interval. of' surveillance proposed by' the licensee for any transmitters -  !

included in the enhanced. surveillance monitoring program.

.Many.Rosemount transmitter failures have been attributed to the use of  !

stainless- steel "0"-rings between the sensing module and the process flanges.  !

Rosemount improved'the manufacturing process for transmitters ~ manufactured l after July'll, 1989. Those improvements included a limit of the torque applied to the flange bolts. .This limits the stress' caused in the' sensing l module by the "0"-ring. Post-production screening, including pressure testing i of the sensing module for this potential latent defect,.was also implemented  ;

at that time. Therefore, as described in Supplement 1 of NRC Bulletin 90-01, '

those Rosemount transmitters manufactured after July 11, 1989, are not subject  ;

to this review. i i

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2. .NRC~SPECIFIED REQUESTED ACTIONS t

w The NRC stafff spectfied. the following' Requested Actions of licensees.ofl operating reactors. ]  !

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Review plant records.and identify the following Rosemount transmitters j

'(if manufactured before July 11,1989).thateitherareused.inormaybei l used in.either safety-related or ATWS mitigating systems.

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• - Rosemount Model 1153, Series B 9 Rosemount Model Il53, Series D 1

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Rosemount Model 1154

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Ft,llowing identification, the licensee is to establish the following: 1 a.

For those -identified transmitters having a normal. operating

' pressure greater than 1500 psi, and are installed as part of. .;

reactor protection trip systems,'ESF actuation systems,'or ATWS:

mitigating systems, either replace the transmitter in' an expedited:

1 manner, or monitor monthly, for the' life of. the transmitter, using  ;

o an enhanced surveillance program.

If the identified transmitter exceeds the 60,000 psi-month.or the  !

130,000 psi-month criterion (depending on the range code of the j transmitter) established by Rosemount,- enhanced surveillance on a-i refueling (not exceeding 24 months) basisiis acceptable. ;Under this option, justification ^must be-based on the service record and the specific safety . function of the ' transmitter. .That . '

justification can be based!on high-functional reliability provided by redundancy or diversity. 1 i

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For those identified transmitters having a normal. operating-pressure greater than 1500 psi, and are installed as part of'a i safety-related system other than reactor protection trip systems, i ESF actuationior ATWS mitigating systems, either replace the  ;

transmitter or monitor quarterly; for. the life of the transmitter, 9 1

using an enhanced surveillance program.-

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'If the identified transmitter exceeds the 60,000 psi-month or the. '

130,000 psi-month criterion (depending on the range code'of the 1 transmitter) established by Rosemount, enhanced surveillance on a i

refueling (not exceeding 24 months) basis is acceptable. Under this option, justification must be based on the' service record and  !

1 the specific safety function of the transmitter. That i 1

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justification can be' based on high: functional reliability provided: l by redundancy orLdiversity..

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c.. For: boiling 7 water; reactors-(BWR)-- , -1

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- For those identified _ transmitters having.a normal' operating j

g'  ;; _ pressure greater than.500 psi _ and less ~ than or' equal to 1

.1500 psi, and'are installed as:part'of reactor protectionL '

j trip systems,,ESF actuation systems'.or ATWS mitigating

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with'an' enhanced surveillance monitoring program .until.the' ,

transmitter reaches the designated (by Rosemount)l psi-month '

criterion!(60,000 psi-monthor 130,000 psi-month,* depending-on'the transmitter range code)'.

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1 For transmitters.that-provide signals to the RPS or"ATWS l

, __ trips for.high pressure or low water level, the' enhanced 1

im surveillance must be monthly. For:other transmitters;in J L this classification, enhanced surveillance on a. refueling 1

(not exceeding.24 months). basis is acceptable.' . Under this j option, justification must be based nn the service. record. 1 and.the specific safety function of_ the transmitter.1 'That. '

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, -justification can be based on high functional; reliability _. .

~ provided by redundancy or diversity- -

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For pressurized water reactors (PWR)-- 1 i

For those identified transmitters having a normal operating j pressure greater than 500 psi and less _ than or equal'to. j 1500 psi, and are. installed as:part of-reactor protection 1 trip' systems, ESF. actuation systems,-or'ATWS~ mitigating j systems, either replace the transmitter, or monitor with anc  !

. enhanced surveillance monitoring. program, until the .

J transmitter reaches.the designated (by Rosemount) psi-month _ l criterion (60,000 psi-month-or 130,000 psi-month,cdepending ,

on the' transmitter range' code) on a refueling'-(not exceeding' 24 months) basis.

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d. . For those identified transmitters having a normal operating-  ;

pressure greater than 500 psi and less than or. equal to- 1500 psi, j and are installed as part of a safety-related system other than^

^ q reacter protection trip systems, ESF actuation, or ATWS mitigating 1 systems, either replace the transmitter orfmonitor with an '

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, enhanced surveillance monitoring. program,_ until the transmitter i!

reachesthedesignated(byRosemount) psi-monthcriterion--(60,000- 1 psi-month or 130,000 psi-month,. depending on the transmitter range j code) ion a refueling (not exceeding 24 months). basis.

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th'R e.- Those: transmitters having a' normal: operating pressure greater than'

i 500 psi and..less than or equal to 1500 psi, and have accumulated i

sufficient psi-month operating history to exceed the criterion" established by Rosemount,:may be excluded fromLthe enhanced -

surveillance monitoring program at the discretion of the licensee. "

However, the licensee should retain a high level of confidence i

- that.a high level of reliability is-maintained and that . r -

transmitter failure due to-loss of fill-oil is detectable.T f.

Those' transmitters having a normal operating pressure less than or.

equal to 500 psi may be excluded from the enhanced surveillance-monitoring program'at the discretion of the licensee. However,' ._. o'

'. the' licensee -should retain:a high level of confidence. that' a high: '

level of reliability is maintained and that transmitter failure a

.due to loss'of fill-oil is detectable. ,

7 Evaluate the enhanced . surveillance monitoring. program. The: evaluation  !

2. i is to ensure the measurement data has an accuracy commensurate with_the._

accuracy needed to compare the data to the manufacturers drift. data criteria.. It is this comparison that determines the degradation j

. threshold for loss of fill-oil failures of the subject transmitters; }

'i The Supplement also' states the NRC may conduct audits or inspections in) f' the future to verify compliance with-the established' requirements.

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~3'. EVALUATION  ;

The licensee provided a' response to Supplement 1:of. NRC Bulletin 90-01" '!

.' on March 4, 1993.)-The licensee: submitted' additional inforuation and 1

clarifying statements on September 29, 1993, and January 31, 1995. The.  !

licensee reports, in Reference 3, having'112 Rosemount transmitters, 56 in i each unit, subject to the Requested Actions of the Supplement. This amount differs as-the licensee replaces. or- refurbishes transmitters. The_ licensee' ll

t states they_ comply with the _ requirements of the Supplement. The response was compared to the Bulletin Reporting Requirements and Requested Actions as. I described below. i j .

3.1 Evaluation of Licensee Response to Reportino Reauirements The licensee states they comply with the Requested Actions detailed in -

Supplement 1 of NRC Bulletin 90-01. The Supplement has. specific Reporting- d Requirements. The licensee submittals address these Reporting Requirements.

As described.in Section 3.3.8, the Reference 4 submittal describes the - .

enhanced surveillance monitoring program. The submittal describes specific actions taken in the enhanced surveillance monitoring program. The licensee: j listed specific actions, _ including any justifications,'taken to comply with the Requested Actions of the Supplement. As the-licensee commitments do not- 1 include modificai; ions or transmitter replacements, there is no schedule for .

completion. However, the licensee will remove a transmitter from the enhanced q

surveillance monitoring program if replaced or refurbished later. The licensee identifies Requested Actions not taken, and provides an evaluation  !

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describing the basis for that exemption.

3.2- Evaluation of Licensee Resoonse to Reauested Actions Supplement 1 of NRC Bulletin 90-01 requested licensee action to resolve ]

the issue of fill-oil leakage in Rosemount transmitters. In this Technical Evaluation Report, the Requested Actions and associated transmitter' criteria 7

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i are summarized in Section 2. The licensee identified a total of.56 transmitters that are in the scope of this review at each South Texas unit when making their initial response in March 1993. The licensee has no ,

Rosemount model 1154 transmitters in the scope of this review. The licensee response is discussed in the following sections.

-3.2.1 Licensee Response to Reauested Action 1.a.

-The licensee states there are no Rosemount transmitters from this t transmitter classification at' the South Texas Project.

3.2.2 Licensee Response to Reauested Action 1.b.

The licensee states there are two Rosemount transmitters from this transmitter classification at the South Texas Project. These two transmitters have exceeded the 60,000 psi-month maturity criterion established by Rosemount and endorsed by the NRC. These two transmitters will remain installed with surveillance testing every 18 months. This calibration data is trended.

Supplement I to NRC Bulletin 90-01 specifically requires the licensee to justify the interval of the enhanced surveillance monitoring program for mature transmitters in this transmitter classification if the interval is less -

frequent than quarterly.

The licensee states that each of these Rosemount transmitters monitors  ;

the reactor coolant system (RCS) pressure, one at each unit. Each unit has ,

two additional RCS pressure transmitters, not manufactured by Rosemount. -

Thus, the non-Rosemount transmitters are not susceptible to the same failure  !

mechanism. The Qualified Display Processing System (QDPS) continually compares the signal from each of these three transmitters (per unit) to the- ,

average value of the three signals. The QDPS flags an outlying indication for the control room operators. Based on the transmitter diversity, redundancy, i and continual monitoring by the QDPS, and that these Rosemount transmitters ,

have exceeded their 60,000 psi-month maturity criterion, we find the refueling i 8 -

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1 outage intervalifor the enhanced surveillance of these transmitters i

acceptable..

, 1 The licens'ee states that.when enough. data is accumulated to show these.

O- transmitters have no. symptoms of loss of' fill-oil, they wil1: discontinue

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3  : trending.of the calibration drift data. The Supplement makes no allowance for- >

P ending the' active' monitoring of the condition of Rosemount transmitters thati

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operate'above 1500Tpsi. However, as long as the QDPS actively monitors the

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output:of these' transmitters in' comparison to the average value _of the three' redundant transmitters, discontinuing the trending of' calibration' drift data is acceptable. - Likewise, with transmitter replacement, excluding the -

L, replacement transmitter from the enhanced surveillance monitoring program is, acceptable.

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~ 3.2.3 Licensee Resoonse to Reouested Action-1.c.

.The licensee states there are eight Rosemount' transmitters-from this.

F- transmitter classification at the South Texas Pro. ject. These transmitters have not' exceeded the 130,000 psi-month criterion established by'Rosemount and endorsed by the NRC. The licensee. committed to perform preventive maintenance I on these transmitters with.a'26-week interval'between maintenance periods.

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The preventive, maintenance includes calibration. TheLlicensee states th'ey will trend calibration data, enhancing the preventive maintenance- program. .j This satisfies the requirements of the Supplement and is acceptable.-

.1 Reference 4 indicates that -the' licensee'. replaced four (4) transmitters from this transmitter classification at Unit 2 with new transmitters, or.

!' transmitters refurbished with new components, manufactured after July 11, 1989. Thus, this classification is no longer applicable at Unit 2.

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.'3.2.4 Licensee Response to Reauested Action 1.d.

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_ The licensee statesithere.are 18'Rosemount transmitters from this transmitter classification 'at. the South Texas' Project. Fourteen of these. i transmi,tters have exceeded the 60,000 psi-month' criterion' established by~- '!

Rosemount and endorsed by the NRC. ~These transmitters have surveillance.

performed every.18. months coinciding with the refueling cycle. The licensee- .li states they will trend the calibration data'for these transmitters. This .

satisfies the requirementsf of the Supplement and is acceptable. All .

transmitters in this classification will continue'.in the enhanced surveillance  ;

monitoring program until all transmitters have exceeded the 60,000 psi-month:  !!

maturity threshold. Trending of! calibration data will continue for these e transmitters until transmitter replacement or until. the poter,tial- for i degracation of these transmitters caused.by the loss of fill-oil has been. ,

disprov?d (by all transmitters in this classification successfully; reaching  !

their maturity threshold). ,

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3.2.5 Licensee Response to Reauested Action 1.e. .

The licensee states they will exclude Rosemount transmitters in transmitter classification 1.d from the enhanced surveillance monitoring j programthat,asagroup,exceedthepsi-month lthresholdandthe: transmitter. '!

demonstrates that' loss of fill-oil.is not evident. The Supplement permits: i this' action. However, the Supplement requires the licensee to retain a high- j degree of confidence that these transmitters in this classification remain  !

highly reliable. The licensee-states that they perform preventive maintenance j and surveillance monitoring every 18 months. The licensee further states they 'l will continue trending the calibration data for transmitters in this l transmitter classification. This commitment for trending is-acceptable in j providing the necessary confidence in these Rotemount transmitters.

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3.2.6 Licensee Response to Reou!sted Action 1.f. l The licensee states there are'84 Rosemount transmitters from this transmitter classification at the South Texas Project. Six.of these have Technical Specification requirements. Because of this,'these six' transmitters have their calibration data trended every refueling outage. .Thus, the ,

licensee actions for these six transmitters is acceptable.

The licensee does not include the other 78 transmitters from'this transmitter classification in an enhanced surveillance monitoring program.

The Supplement permits this' action. However, the Supplement requires the licensee to retain a high degree of confidence that these transmitters remain.  !

- highly reliable..  !

These transmitters participate in the South Texas Project's Preventive- ,

Maintenance. Program. The licensee bases this program for routine maintenance and calibration on the recommendations of the Rosemount Installation and -

Maintenance Manual. Systems Engineering reviews any out-of-tolerance ,

calibration data. This review determines.the need.for retesting, data trending, or transmitter replacement, based on functional requirements. The  !

licensee states the surveillance monitoring program can detect the loss of.

fill-oil in Rosemnunt transmitters. Based on the licensee discussion of the surveillance monitoring program, we find the licensee response for this transmitter classification acceptable.

1 3.2.7 Soare Transmitters The' licensee states, in Reference 3, that the Restristed Component List ,

will control the use of Rosemount transmitters.in replacement transmitter. j safety-related applications. The licensee states that spare Rosemount transmitters will either participate in the calibration trending program or j used in non safety-related applications. With a transmitter on the Restricted .!

Component List, an evaluation before component use assures use of the j transmitter in an acceptable application.

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k 3.2.8- Enhanced Surveillance Monitorina Proaram ,

The licensee bases their. enhanced surveillance monitoring program on the rctommendations of Rosemount Technical Bulletin No. 4. The licensee maintains a computer database that includes the transmitter'model number,-serial number, when initially pressurized, time at pressure, and confirmation against the suspect list of transmitter serial numbers (provided by Rosemount). The licensee trends the calibration data, adding it to their database when obtained from preventive maintenance surveillance. The licensee states-the ,

surveillance program is adequate to detect degradation-caused by loss of fill-oil. The licensee trends the calibration data (accumulative zero and span drift) and compares the accumulated drift to the drift limits set in Rosemount .

Technical Bulletin No. 4. The licensee states that if the trended data shows ,

the possibility of degradation due to the loss of fill-oil, they send the data to Rosemount for confirmation that the transmitter needs replacement.

The licensee states the enhanced surveillance monitoring program will continue until all included transmitters are either replaced or the maturity threshold is exceeded for all transmitters in transmitter classifications 1.c i and 1.d, with no evidence of degradation caused by the loss of fill-cil.

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CONCLUSIONS Based on our review, we find that the licensee has completed the .I reporting requirements of Supplement 1 of NRC Bulletin 90-01. Further, the- l licensee either conforms to or has adequate. justification for deviating from the requested actions of Supplement I to NRC Bulletin 90-01.

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5. REFERENCES ,

11.- NRC Bulletin No. 90-01: " Loss of Fill-oil in Transmitters Manufactured 1 by Rosemount," March 9, 1990, 0MB No. 3150-0011.  !

2. NRC Bulletin No. 90-01, Supplement 1:' " Loss of Fill-oil in Transmitters  !

Manufactured by Rosemount," December 22, 1992, OMB No. 3159-0011. i

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3. Letter, Houston Lighting and Power. Company (S. L. Rosen) to NRC, '

" Response to NRC Bulletin No. 90-01, ' Loss of F111-011 in Transmitters Manufactured by Rosemount'," March 4, 1993, ST-HL-AE-4346, File No.: 3 G03.03.

4. Letter, Houston Lighting and Power Company (T. H. Cloninger) to NRC, .

" Supplemental Response to NRC Bulletin No. 90-01, ' Loss of F111-011 in Transmitters Manufactured by Rosemount'," September 29, 1993, ,

ST-HL-AE-4559, File No.: G03.03. *

5. Letter, Houston Lighting and Power Company (T. H. Clo..'ager) to NRC,

" Additional Information in Response to NRC Bulletin No. ,2-01, ' Loss of Fill-011 in Transmitters Manufactured by Rosemount'," January-31,1995, ,

ST-HL-AE-4957, File No.: G03.03. l t

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