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| issue date = 09/30/1994 | | issue date = 09/30/1994 | ||
| title = Errata to TER, Evaluation of Util Response to Suppl 1 to NRC Bulletin 90-001,St Lucie 1 & 2, Replacing Every Other Missing Page in Original Rept | | title = Errata to TER, Evaluation of Util Response to Suppl 1 to NRC Bulletin 90-001,St Lucie 1 & 2, Replacing Every Other Missing Page in Original Rept | ||
| author name = | | author name = Udy A | ||
| author affiliation = EG&G IDAHO, INC., IDAHO NATIONAL ENGINEERING & ENVIRONMENTAL LABORATORY | | author affiliation = EG&G IDAHO, INC., IDAHO NATIONAL ENGINEERING & ENVIRONMENTAL LABORATORY | ||
| addressee name = | | addressee name = | ||
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| page count = 21 | | page count = 21 | ||
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=Text= | |||
{{#Wiki_filter:EGG-DNSP-11487 TECHNICAL EVALUATION REPORT Evaluation of Utility Response to Supplement 1 to NRC Bulletin 90-01: St. Lucie-I/-2 Docket Nos. 50-335 and 50-389 Alan C. Udy Published Septemb'er 1994 EGSG Idaho, Inc. | |||
Idaho National Engineering Laboratory Idaho Falls, Idaho 83415 Prepared for the U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Under DOE Contract No. DE-AC07-76ID01570 FIN No. L1695, Task No. 11a TAC Nos. M85446 and M85447 PDR P -,; | |||
e4~0a50149 e40e30 ADOCK 05000335 | |||
.PDR | |||
~i | |||
0 \ ~ | |||
==SUMMARY== | |||
This report documents the EGKG Idaho, Inc., review of the Florida Power and Light Company submittals that respond to Supplement 1 to NRC Bulletin 90-01 for Unit Nos. 1 and 2 of the St. Lucie Plant. This NRC Bulletin provides information regarding the loss of fill-oil in certain pressure and differential pressure transmitters manufactured by Rosemount, Inc. This report finds that the licensee complies to the requested actions and the reporting requirements of the Supplement. | |||
FIN No. L1695, Task No. lla BER No. 320-19-15-05-0 Docket Nos. 50-335 and 50-389 TAC Nos. M85446 and M85447 | |||
e PREFACE 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 EGLG Idaho, Inc., DOE/NRC Support Programs Unit. | |||
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CONTENTS S UMMARY o ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ t ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ tt ~ ~ ~ ~ ~ ~ ~ ~ ~ | |||
P REFACE .............................................................. ill | |||
: 1. INTRODUCTION .. ~...........................................,..... 1 | |||
: 2. NRC SPECIFIED RE(UESTED ACTIONS ................................. 4 | |||
: 3. E VALUATION .....;................................................ 7'. | |||
1 Evaluation of Licensee Response to Reporting Requirements . 7 3.2 Evaluation of Licensee Response to Requested Actions ...... 7 | |||
: 4. CONCLUSIONS .. ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ t ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 12 | |||
: 5. R EFERENCES ...................................................... 13 | |||
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Evaluation of Utilit Res onse to Su lement 1 to NRC Bulletin 90-01: St. Lucie-1 -2 | |||
: 1. INTRODUCTION The NRC issued Bulletin 90-01 on March 9, 1990 (Reference 1). That Bulletin discussed certain, Rosemount pressure and differential pressure transmitter models identified by the manufacturer as prone to fill-oil leakage. The Bulletin requested licensees to identify whether these transmitters were or may later be installed in safety-related systems. | |||
Actions were detailed for licensee implementation for certain identified transmitters installed in a safety-related system.. These same actions apply to those identified transmitters presently held in inventory for later installation in a safety-related system. | |||
With the gradual leakage of fill-oil, the transmitter would not have the long term accuracy, time response, and reliability needed for its intended safety function. Further, this condition could go undetected over a long period. Redundant 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 transient without scram (ATWS) mitigating systems. To achieve high functional reliability, there must be a low probability of component failure while operating, with any failures readily detectable. | |||
Supplement 1 to NRC Bulletin 90-01 (Reference 2) was issued on December 22, 1992. The Supplement informed licensees of NRC staff activities regarding the subject transmitters, and noted continuing reports of transmitter failures. The'RC requested licensee action to resolve the issue. | |||
The Supplement also updated the. information contained in the original bulletin. The licensee was requested to review the information and determine if it was applicable at their facility. Further, the licensee was requested to modify their actions and enhanced surveillance monitoring programs to conform with the direction given. Finally, the licensee was instructed to 1 | |||
respond to the NRC. ,The Re uested Actions in Supplement 1 to NRC Bulletin 90-Ol supersede the original NRC Bulletin 90-01 Re uested Actions. | |||
In responding to Supplement 1 to NRC Bulletin 90-01, the licensee is directed to address three items. | |||
: l. A statement either committing the licensee to take the NRC Bulletin 90-01, Supplement 1, Re uested 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, Re uested Actions not taken, along with an evaluation providing the basis for exemption. | |||
In implementing the replacement'ption of the NRC Re uested 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 Florida Power and Light Company, the licensee for Unit Nos. 1 and 2 of the St. Lucie Plant, responded to Supplement 1 of NRC Bulletin 90-01 with a letter dated Harch 5, 1993 (Reference 3). The licensee provided additional information on March 9, 1994 (Reference 4). The licensee notified the NRC that their transmitter replacements were complete on August 18, 1994 (Reference 5). This technical evaluation report evaluates the completeness o' 2 | |||
those submittals. It also determines whether proposed surveillance methods are adequate to determine fill-oil loss-caused degradation of the transmitter.. | |||
Finally, this report addresses the interval of surveillance proposed by the licensee for 'any transmitters included in the enhanced surveillance monitoring program. | |||
Hany 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 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 module by the "0"-ring. Post-production screening, including pressure testing 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. | |||
: 2. NRC SPECIFIED REQUESTED ACTIONS The NRC staff specified the following Re uested Actions of licensees of operating reactors. | |||
: 1. Review plant records and identify the following Rosemount transmitters (if manufactured before July 11, 1989) that either are used in or may be used in either safety-related or ATWS mitigating systems. | |||
Rosemount Hodel 1153, Series B Rosemount Hodel 1153, Series D Rosemount Hodel 1154 Following identification, the licensee is to establish the following: | |||
'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 manner, or monitor monthly, for the life of the transmitter, using 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 transmitter) established by Rosemount, enhanced surveillance on a refueling (not exceeding 24 months) basis is 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. | |||
: b. For those identified transmitters having a normal operating pressure greater than 1500 psi, and are installed as part of a safety-related system other than reactor protection trip systems, ESF actuation, or ATWS mitigating systems, either replace the transmitter or monitor quarterly, for the life of the transmitter, using 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 transmitter) established by Rosemount, enhanced surveillance on a refueling (not exceeding 24 months) basis is 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. | |||
For boiling water reactors (BWR)-- | |||
For those identified transmitters having a normal operating pressure greater than 500 psi and less than or equal to 1500 psi, and are installed as part of reactor protection trip systems, ESF actuation systems, or ATWS mitigating systems, either replace the transmitter, or monitor monthly with an enhanced surveillance monitoring program, until the transmitter reaches the designated (by Rosemount) psi-month criterion (60,000 psi-month or 130,000 psi-month, depending on the transmitter range code). | |||
For transmitters that provide signals to the RPS or ATWS trips for high pressure or low water level, the enhanced surveillance must be monthly. For other transmitters in this classification, enhanced surveillance on a refueling (not exceeding 24 months) basis is 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. | |||
For pressurized water reactors (PWR)-- | |||
For those identified transmitters having a normal operating pressure greater than 500 psi and less than or equal to 1500 psi, and are installed as. part of reactor protection trip systems, ESF actuation systems, or ATWS mitigating systems, either replace the transmitter, or monitor with an enhanced surveillance monitoring program, until the transmitter reaches the designated (by Rosemount) psi-month criterion (60,000 psi-month or 130,000 psi-month, depending on the transmitter range code) on a refueling (not exceeding 24 months) basis. | |||
For those identified transmitters having a normal operating pressure greater than 500 psi and less than or equal to 1500 psi, and are installed as part of a safety-related system other than reactor protection trip systems, ESF actuation, or ATWS mitigating systems, either replace the transmitter, or monitor with an enhanced surveillance monitoring program, until the transmitter reaches the designated (by Rosemount) psi-month criterion (60,000 psi-month or 130,000 psi-month, depending on the transmitter range code) on a refueling (not exceeding 24 months) basis. | |||
: e. Those transmitters having a normal operating pressure greater than 500 psi and less than or equal to 1500 psi, and have accumulated sufficient psi-month operating history to exceed the criterion established by Rosemount, may be excluded from the enhanced survei.llance monitoring program at the discretion of the licensee. | |||
However, the licensee should retain a high'evel of confidence that a high level of reliability is maintained and that transmitter failure due to loss of fill-oil is detectable. | |||
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, the licensee should retain a high level of confidence that a high level of reliability is maintained and that transmitter failure due to loss of fill'-oil is detectable. | |||
: 2. Evaluate the enhanced surveillance monitoring program. The evaluation 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 threshold for loss of fill-oil failures of the subject transmitters. | |||
The Supplement also states the NRC may conduct audits or inspections in the future to verify compliance with the established requirements. | |||
: 3. EVALUATION The licensee responded to Supplement 1 of NRC Bulletin 90-01 on March 5, 1993. The licensee provided additional information on March 9, 1994. The licensee notified the NRC that their transmitter replacements were complete on August 19, 1994. Those responses were compared to the Bulletin ~Re ortin d d i d ib d b 1 . Th having Rosemount transmitters that are subject to the Re uested Actions of the Supplement. Other Rosemount transmitters are'outside the scope of the Supplement due to replacement or refurbishment. | |||
: 3. 1 Evaluation of Licensee Res onse to Re ortin Re uirements The licensee states, in Reference 3, that they intend to implement the Re uested Actions detailed in Supplement 1 of NRC Bulletin 90-01. Included with that statement is clarification, interpretation, and the limits placed on that commitment. The licensee described the specific actions taken to execute the Re uested Actions. The licensee provided a statement that the ~Re uested Actions are complete on August 18, 1994. | |||
The licensee submitt'als conform to the Re ortin Re uirements of Supplement 1 of NRC,Bulletin 90-01. | |||
3.2 Evaluation of Licensee Res onse to Re uested Actions Supplement 1 of NRC Bulletin 90-01 requested licensee action to resolve the issue of fill-oil leakage in Rosemount transmitters. This Technical Evaluation Report summarizes the Re uested Actions and the associated transmi'tter criteria in Section 2. Rosemount transmitters manufactured after July 11, 1989 are not subject to the Supplement requirements or an enhanced surveillance monitoring program. The licensee'esponse to the Supplement is discussed in the following sections. | |||
3.2. 1 Licensee Res onse to Re uested Action 1.a Unit No. 1 The licensee states there are Rosemount transmitters from this transmitter classification at Unit No. 1 of the St. Lucie Plant. The licensee scheduled the subject transmitters for replacement in the spring of 1993. | |||
However, the licensee commi.tted that if a delay in transmitter installation occurred, the licensee will monitor that transmitter monthly as part of their enhanced surveillance monitoring program. The licensee stated they will not increase the surveillance interval from monthly without providing justification to the NRC. The licensee actions for transmitters in transmitter classification l.a at Unit No. 1 are acceptable. As noted in Reference 5, the licensee actions for this transmitter classification are complete, and the transmitters replaced as scheduled. | |||
Unit No. 2 The licensee states there are Rosemount transmitters from this transmitter classification at Unit No. 2 of the St. Lucie Plant. However, all Unit No. 2 Rosemount transmitters in this transmitter classification were manufactured after July 11, 1989, and are exempt from the Supplement requirements. | |||
3.2.2 Licensee Res onse to Re uested Action 1.b. | |||
Unit No. 1 The licensee states there are Rosemount transmitters from this transmitter classification at Unit No. 1 of the St. Lucie Plant. The licensee scheduled the subject transmitters for replacement in the spring of 1993. | |||
However, the licensee committed, in Reference 3, that if a delay in transmitter installation occurred, the licensee will monitor that transmitter | |||
quarterly as part of their enhanced surveillance monitoring program. The licensee states they will not increase the surveillance interval from quarterly without providing justification to the NRC. The licensee actions for transmitters in transmitter classification 1.b at Unit No. 1 are acceptable. As noted in Reference 5, the licensee actions for this transmitter classification are complete, and the transmitters replaced. as scheduled. | |||
Unit No. 2 The licensee states there are Rosemount transmitters from this transmitter classification at Unit No. 2 of the St. Lucie Plant. The licensee scheduled the subject transmitters for replacement in the fall of 1993. The licensee committed, in Reference 3, to monitor these transmitters quarterly as part of the enhanced surveillance monitoring program until replaced. Some of the Unit No. 2 Rosemount transmitters were manufactured after July ll, 1989, and are exempt from the Supplement requirements. The licensee actions for transmitters in transmitter classification 1.b at Unit No. 2 are acceptable. | |||
As noted in Reference 5, the licensee actions for this transmitter classification are complete, and the transmitters replaced as scheduled. | |||
3.2.3 Licensee Res onse to Re uested Action 1.c The licensee states there are Rosemount transmitters from this transmitter classification at the St. Lucie Plant. The licensee states that these transmitters will participate in an enhanced surveillance monitoring program on a refueling basis. The interval will not exceed 24 months. Either replacement or successfully achieving the psi-month maturity threshold will remove a transmitter from the enhanced surveillance monitoring program. | |||
Replacement with a transmitter manufactured after July 11, 1989, removes the transmitter from the Supplement requirements. Successfully achieving maturity transfers the transmitter to transmitter classification l.e. See Section 3.2.5. | |||
3.2.4 Licensee Res onse to Re uested Action 1.d The licensee states there are Rosemount transmitters from this transmitter classification at the St. Lucie Plant. The licensee states that these transmitters will participate in an enhanced surveillance-monitoring program on a refueling basis. The interval will not exceed 24 months. Either replacement or successfully achieving the psi-month maturity threshold will remove'a transmitter from the enhanced surveillance monitoring program. | |||
Replacement with a transmitter manufactured after July 11, 1989, removes the transmitter from the Supplement requirements. Successfully achieving maturity transfers the transmitter to transmitter classification l.e. See Section 3.2.5. | |||
3.2.5 Licensee Res onse to Re uested Action l.e As transmitters in transmitter classification 1.c and 1.d exceed the psi-month maturity threshold, the licensee will remove those transmitters from the enhanced surveillance monitoring program. The Supplement'ermits this action. | |||
The Supplement requires the licensee to maintain a high degree of confidence that these transmitters remain highly reliable. The licensee states that before removing a transmitter from the enhanced surveillance monitoring program, the transmitter will exhibit no excessive drift or sluggishness. The licensee states that existing maintenance and surveillance programs can detect future failures due to the loss of fill-oil. | |||
3.2.6 Licensee Res onse to Re uested Action 1.f The licensee states there are Rosemount transmitters from this classification at the St. Lucie Plant. At licensee discretion, these transmitters are not part of the enhanced surveillance monitoring program. | |||
The Supplement permits this action. | |||
10 | |||
The Supplement requires the licensee to maintain a high degree of confidence that these transmitters remain highly reliable. The l,icensee states that existing maintenance and surveillance programs can detect future failures due to the loss of fill-oil. | |||
3.2.7 Enhanced Surveillance Nonitorin Pro ram The licensee described the monitoring'intervals for the different transmitter classifications. The licensee, in addressing Re uested Action 2 of the Supplement, states their enhanced surveillance monitoring program uses the guidelines of Rosemount Technical Bulletin No. 4. Following the guidelines of Rosemount Technical Bulletin No. 4 satisfies the requirements of the Supplement and is acceptable. | |||
: 4. CONCLUSIONS Based on our review, we find the licensee has completed the reporting requirements of Supplement 1 of NRC Bulletin 90-01. Further, the licensee conforms to the Re uested Actions of Supplement 1 to NRC Bulletin 90-01. | |||
12 | |||
: 5. REFERENCES NRC Bulletin No. 90-01: "Loss of Fill-oil in Transmitters Manufactured by Rosemount," March 9, 1990, OHB No. 3150-0011. | |||
NRC Bulletin No. 90-01, Supplement 1: "Loss of Fill-oil in Transmitters Manufactured by Rosemount," December 22, 1992, OMB No. 3150-0011. | |||
Letter, Florida. Power and Light Company (D. A. Sager) to NRC, "NRC Bulletin 90-01 Supplement 1 Response," March 5, 1993, L-93-61. | |||
Letter, Florida Power and Light Company (D. A. Sager) to NRC, "NRC Bulletin 90-01 Supplement 1 Additional Information," March 9, 1994, L-94-061. | |||
L'etter, Florida Power and Light Company (D. A. Sager) to NRC, "NRC Bulletin 90-01 Supplement 1 Additional Information," August 18, 1994, L-94-210. | |||
13}} |
Latest revision as of 13:33, 4 February 2020
ML17228A885 | |
Person / Time | |
---|---|
Site: | Saint Lucie ![]() |
Issue date: | 09/30/1994 |
From: | Udy A EG&G IDAHO, INC., IDAHO NATIONAL ENGINEERING & ENVIRONMENTAL LABORATORY |
To: | NRC |
Shared Package | |
ML17228A883 | List: |
References | |
CON-FIN-L-1695 EGG-DNSP-11487, EGG-DNSP-11487-ERR, IEB-90-001, IEB-90-1, TAC-M85446, TAC-M85447, NUDOCS 9410250149 | |
Download: ML17228A885 (21) | |
Text
EGG-DNSP-11487 TECHNICAL EVALUATION REPORT Evaluation of Utility Response to Supplement 1 to NRC Bulletin 90-01: St. Lucie-I/-2 Docket Nos. 50-335 and 50-389 Alan C. Udy Published Septemb'er 1994 EGSG Idaho, Inc.
Idaho National Engineering Laboratory Idaho Falls, Idaho 83415 Prepared for the U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Under DOE Contract No. DE-AC07-76ID01570 FIN No. L1695, Task No. 11a TAC Nos. M85446 and M85447 PDR P -,;
e4~0a50149 e40e30 ADOCK 05000335
.PDR
~i
0 \ ~
SUMMARY
This report documents the EGKG Idaho, Inc., review of the Florida Power and Light Company submittals that respond to Supplement 1 to NRC Bulletin 90-01 for Unit Nos. 1 and 2 of the St. Lucie Plant. This NRC Bulletin provides information regarding the loss of fill-oil in certain pressure and differential pressure transmitters manufactured by Rosemount, Inc. This report finds that the licensee complies to the requested actions and the reporting requirements of the Supplement.
FIN No. L1695, Task No. lla BER No. 320-19-15-05-0 Docket Nos. 50-335 and 50-389 TAC Nos. M85446 and M85447
e PREFACE 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 EGLG Idaho, Inc., DOE/NRC Support Programs Unit.
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CONTENTS S UMMARY o ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ t ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ tt ~ ~ ~ ~ ~ ~ ~ ~ ~
P REFACE .............................................................. ill
- 1. INTRODUCTION .. ~...........................................,..... 1
- 2. NRC SPECIFIED RE(UESTED ACTIONS ................................. 4
- 3. E VALUATION .....;................................................ 7'.
1 Evaluation of Licensee Response to Reporting Requirements . 7 3.2 Evaluation of Licensee Response to Requested Actions ...... 7
- 4. CONCLUSIONS .. ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ t ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 12
- 5. R EFERENCES ...................................................... 13
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Evaluation of Utilit Res onse to Su lement 1 to NRC Bulletin 90-01: St. Lucie-1 -2
- 1. INTRODUCTION The NRC issued Bulletin 90-01 on March 9, 1990 (Reference 1). That Bulletin discussed certain, Rosemount pressure and differential pressure transmitter models identified by the manufacturer as prone to fill-oil leakage. The Bulletin requested licensees to identify whether these transmitters were or may later be installed in safety-related systems.
Actions were detailed for licensee implementation for certain identified transmitters installed in a safety-related system.. These same actions apply to those identified transmitters presently held in inventory for later installation in a safety-related system.
With the gradual leakage of fill-oil, the transmitter would not have the long term accuracy, time response, and reliability needed for its intended safety function. Further, this condition could go undetected over a long period. Redundant 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 transient without scram (ATWS) mitigating systems. To achieve high functional reliability, there must be a low probability of component failure while operating, with any failures readily detectable.
Supplement 1 to NRC Bulletin 90-01 (Reference 2) was issued on December 22, 1992. The Supplement informed licensees of NRC staff activities regarding the subject transmitters, and noted continuing reports of transmitter failures. The'RC requested licensee action to resolve the issue.
The Supplement also updated the. information contained in the original bulletin. The licensee was requested to review the information and determine if it was applicable at their facility. Further, the licensee was requested to modify their actions and enhanced surveillance monitoring programs to conform with the direction given. Finally, the licensee was instructed to 1
respond to the NRC. ,The Re uested Actions in Supplement 1 to NRC Bulletin 90-Ol supersede the original NRC Bulletin 90-01 Re uested Actions.
In responding to Supplement 1 to NRC Bulletin 90-01, the licensee is directed to address three items.
- l. A statement either committing the licensee to take the NRC Bulletin 90-01, Supplement 1, Re uested 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, Re uested Actions not taken, along with an evaluation providing the basis for exemption.
In implementing the replacement'ption of the NRC Re uested 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 Florida Power and Light Company, the licensee for Unit Nos. 1 and 2 of the St. Lucie Plant, responded to Supplement 1 of NRC Bulletin 90-01 with a letter dated Harch 5, 1993 (Reference 3). The licensee provided additional information on March 9, 1994 (Reference 4). The licensee notified the NRC that their transmitter replacements were complete on August 18, 1994 (Reference 5). This technical evaluation report evaluates the completeness o' 2
those submittals. It also determines whether proposed surveillance methods are adequate to determine fill-oil loss-caused degradation of the transmitter..
Finally, this report addresses the interval of surveillance proposed by the licensee for 'any transmitters included in the enhanced surveillance monitoring program.
Hany 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 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 module by the "0"-ring. Post-production screening, including pressure testing 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.
- 2. NRC SPECIFIED REQUESTED ACTIONS The NRC staff specified the following Re uested Actions of licensees of operating reactors.
- 1. Review plant records and identify the following Rosemount transmitters (if manufactured before July 11, 1989) that either are used in or may be used in either safety-related or ATWS mitigating systems.
Rosemount Hodel 1153, Series B Rosemount Hodel 1153, Series D Rosemount Hodel 1154 Following identification, the licensee is to establish the following:
'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 manner, or monitor monthly, for the life of the transmitter, using 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 transmitter) established by Rosemount, enhanced surveillance on a refueling (not exceeding 24 months) basis is 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.
- b. For those identified transmitters having a normal operating pressure greater than 1500 psi, and are installed as part of a safety-related system other than reactor protection trip systems, ESF actuation, or ATWS mitigating systems, either replace the transmitter or monitor quarterly, for the life of the transmitter, using 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 transmitter) established by Rosemount, enhanced surveillance on a refueling (not exceeding 24 months) basis is 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.
For boiling water reactors (BWR)--
For those identified transmitters having a normal operating pressure greater than 500 psi and less than or equal to 1500 psi, and are installed as part of reactor protection trip systems, ESF actuation systems, or ATWS mitigating systems, either replace the transmitter, or monitor monthly with an enhanced surveillance monitoring program, until the transmitter reaches the designated (by Rosemount) psi-month criterion (60,000 psi-month or 130,000 psi-month, depending on the transmitter range code).
For transmitters that provide signals to the RPS or ATWS trips for high pressure or low water level, the enhanced surveillance must be monthly. For other transmitters in this classification, enhanced surveillance on a refueling (not exceeding 24 months) basis is 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.
For pressurized water reactors (PWR)--
For those identified transmitters having a normal operating pressure greater than 500 psi and less than or equal to 1500 psi, and are installed as. part of reactor protection trip systems, ESF actuation systems, or ATWS mitigating systems, either replace the transmitter, or monitor with an enhanced surveillance monitoring program, until the transmitter reaches the designated (by Rosemount) psi-month criterion (60,000 psi-month or 130,000 psi-month, depending on the transmitter range code) on a refueling (not exceeding 24 months) basis.
For those identified transmitters having a normal operating pressure greater than 500 psi and less than or equal to 1500 psi, and are installed as part of a safety-related system other than reactor protection trip systems, ESF actuation, or ATWS mitigating systems, either replace the transmitter, or monitor with an enhanced surveillance monitoring program, until the transmitter reaches the designated (by Rosemount) psi-month criterion (60,000 psi-month or 130,000 psi-month, depending on the transmitter range code) on a refueling (not exceeding 24 months) basis.
- e. Those transmitters having a normal operating pressure greater than 500 psi and less than or equal to 1500 psi, and have accumulated sufficient psi-month operating history to exceed the criterion established by Rosemount, may be excluded from the enhanced survei.llance monitoring program at the discretion of the licensee.
However, the licensee should retain a high'evel of confidence that a high level of reliability is maintained and that transmitter failure due to loss of fill-oil is detectable.
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, the licensee should retain a high level of confidence that a high level of reliability is maintained and that transmitter failure due to loss of fill'-oil is detectable.
- 2. Evaluate the enhanced surveillance monitoring program. The evaluation 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 threshold for loss of fill-oil failures of the subject transmitters.
The Supplement also states the NRC may conduct audits or inspections in the future to verify compliance with the established requirements.
- 3. EVALUATION The licensee responded to Supplement 1 of NRC Bulletin 90-01 on March 5, 1993. The licensee provided additional information on March 9, 1994. The licensee notified the NRC that their transmitter replacements were complete on August 19, 1994. Those responses were compared to the Bulletin ~Re ortin d d i d ib d b 1 . Th having Rosemount transmitters that are subject to the Re uested Actions of the Supplement. Other Rosemount transmitters are'outside the scope of the Supplement due to replacement or refurbishment.
- 3. 1 Evaluation of Licensee Res onse to Re ortin Re uirements The licensee states, in Reference 3, that they intend to implement the Re uested Actions detailed in Supplement 1 of NRC Bulletin 90-01. Included with that statement is clarification, interpretation, and the limits placed on that commitment. The licensee described the specific actions taken to execute the Re uested Actions. The licensee provided a statement that the ~Re uested Actions are complete on August 18, 1994.
The licensee submitt'als conform to the Re ortin Re uirements of Supplement 1 of NRC,Bulletin 90-01.
3.2 Evaluation of Licensee Res onse to Re uested Actions Supplement 1 of NRC Bulletin 90-01 requested licensee action to resolve the issue of fill-oil leakage in Rosemount transmitters. This Technical Evaluation Report summarizes the Re uested Actions and the associated transmi'tter criteria in Section 2. Rosemount transmitters manufactured after July 11, 1989 are not subject to the Supplement requirements or an enhanced surveillance monitoring program. The licensee'esponse to the Supplement is discussed in the following sections.
3.2. 1 Licensee Res onse to Re uested Action 1.a Unit No. 1 The licensee states there are Rosemount transmitters from this transmitter classification at Unit No. 1 of the St. Lucie Plant. The licensee scheduled the subject transmitters for replacement in the spring of 1993.
However, the licensee commi.tted that if a delay in transmitter installation occurred, the licensee will monitor that transmitter monthly as part of their enhanced surveillance monitoring program. The licensee stated they will not increase the surveillance interval from monthly without providing justification to the NRC. The licensee actions for transmitters in transmitter classification l.a at Unit No. 1 are acceptable. As noted in Reference 5, the licensee actions for this transmitter classification are complete, and the transmitters replaced as scheduled.
Unit No. 2 The licensee states there are Rosemount transmitters from this transmitter classification at Unit No. 2 of the St. Lucie Plant. However, all Unit No. 2 Rosemount transmitters in this transmitter classification were manufactured after July 11, 1989, and are exempt from the Supplement requirements.
3.2.2 Licensee Res onse to Re uested Action 1.b.
Unit No. 1 The licensee states there are Rosemount transmitters from this transmitter classification at Unit No. 1 of the St. Lucie Plant. The licensee scheduled the subject transmitters for replacement in the spring of 1993.
However, the licensee committed, in Reference 3, that if a delay in transmitter installation occurred, the licensee will monitor that transmitter
quarterly as part of their enhanced surveillance monitoring program. The licensee states they will not increase the surveillance interval from quarterly without providing justification to the NRC. The licensee actions for transmitters in transmitter classification 1.b at Unit No. 1 are acceptable. As noted in Reference 5, the licensee actions for this transmitter classification are complete, and the transmitters replaced. as scheduled.
Unit No. 2 The licensee states there are Rosemount transmitters from this transmitter classification at Unit No. 2 of the St. Lucie Plant. The licensee scheduled the subject transmitters for replacement in the fall of 1993. The licensee committed, in Reference 3, to monitor these transmitters quarterly as part of the enhanced surveillance monitoring program until replaced. Some of the Unit No. 2 Rosemount transmitters were manufactured after July ll, 1989, and are exempt from the Supplement requirements. The licensee actions for transmitters in transmitter classification 1.b at Unit No. 2 are acceptable.
As noted in Reference 5, the licensee actions for this transmitter classification are complete, and the transmitters replaced as scheduled.
3.2.3 Licensee Res onse to Re uested Action 1.c The licensee states there are Rosemount transmitters from this transmitter classification at the St. Lucie Plant. The licensee states that these transmitters will participate in an enhanced surveillance monitoring program on a refueling basis. The interval will not exceed 24 months. Either replacement or successfully achieving the psi-month maturity threshold will remove a transmitter from the enhanced surveillance monitoring program.
Replacement with a transmitter manufactured after July 11, 1989, removes the transmitter from the Supplement requirements. Successfully achieving maturity transfers the transmitter to transmitter classification l.e. See Section 3.2.5.
3.2.4 Licensee Res onse to Re uested Action 1.d The licensee states there are Rosemount transmitters from this transmitter classification at the St. Lucie Plant. The licensee states that these transmitters will participate in an enhanced surveillance-monitoring program on a refueling basis. The interval will not exceed 24 months. Either replacement or successfully achieving the psi-month maturity threshold will remove'a transmitter from the enhanced surveillance monitoring program.
Replacement with a transmitter manufactured after July 11, 1989, removes the transmitter from the Supplement requirements. Successfully achieving maturity transfers the transmitter to transmitter classification l.e. See Section 3.2.5.
3.2.5 Licensee Res onse to Re uested Action l.e As transmitters in transmitter classification 1.c and 1.d exceed the psi-month maturity threshold, the licensee will remove those transmitters from the enhanced surveillance monitoring program. The Supplement'ermits this action.
The Supplement requires the licensee to maintain a high degree of confidence that these transmitters remain highly reliable. The licensee states that before removing a transmitter from the enhanced surveillance monitoring program, the transmitter will exhibit no excessive drift or sluggishness. The licensee states that existing maintenance and surveillance programs can detect future failures due to the loss of fill-oil.
3.2.6 Licensee Res onse to Re uested Action 1.f The licensee states there are Rosemount transmitters from this classification at the St. Lucie Plant. At licensee discretion, these transmitters are not part of the enhanced surveillance monitoring program.
The Supplement permits this action.
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The Supplement requires the licensee to maintain a high degree of confidence that these transmitters remain highly reliable. The l,icensee states that existing maintenance and surveillance programs can detect future failures due to the loss of fill-oil.
3.2.7 Enhanced Surveillance Nonitorin Pro ram The licensee described the monitoring'intervals for the different transmitter classifications. The licensee, in addressing Re uested Action 2 of the Supplement, states their enhanced surveillance monitoring program uses the guidelines of Rosemount Technical Bulletin No. 4. Following the guidelines of Rosemount Technical Bulletin No. 4 satisfies the requirements of the Supplement and is acceptable.
- 4. CONCLUSIONS Based on our review, we find the licensee has completed the reporting requirements of Supplement 1 of NRC Bulletin 90-01. Further, the licensee conforms to the Re uested Actions of Supplement 1 to NRC Bulletin 90-01.
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- 5. REFERENCES NRC Bulletin No. 90-01: "Loss of Fill-oil in Transmitters Manufactured by Rosemount," March 9, 1990, OHB No. 3150-0011.
NRC Bulletin No. 90-01, Supplement 1: "Loss of Fill-oil in Transmitters Manufactured by Rosemount," December 22, 1992, OMB No. 3150-0011.
Letter, Florida. Power and Light Company (D. A. Sager) to NRC, "NRC Bulletin 90-01 Supplement 1 Response," March 5, 1993, L-93-61.
Letter, Florida Power and Light Company (D. A. Sager) to NRC, "NRC Bulletin 90-01 Supplement 1 Additional Information," March 9, 1994, L-94-061.
L'etter, Florida Power and Light Company (D. A. Sager) to NRC, "NRC Bulletin 90-01 Supplement 1 Additional Information," August 18, 1994, L-94-210.
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