ML20137D075
| ML20137D075 | |
| Person / Time | |
|---|---|
| Site: | Fort Calhoun  |
| Issue date: | 07/17/1985 |
| From: | Andrews R OMAHA PUBLIC POWER DISTRICT |
| To: | Jay Collins NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| IEB-84-02, IEB-84-2, LIC-84-225, NUDOCS 8508220388 | |
| Download: ML20137D075 (7) | |
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Omaha PutWic Power District 1623 Hamey Omaha, Nebraska 68102 402/536 4000 July 17, 1984 L IC-84-225 g@M a
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Mr. J. T. Collins, Administrator U.S. Nuclear Regulatory Commission j
Region IV 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76011
Reference:
Docket No. 50-285
Dear Mr. Collins:
IE Bulletin 84-02: Failures of General Electric Type HFA Relays in Use in Class 1E Safety Systems The Omaha Public Power District received IE Bulletin 84-02 dated March 19, 1984. This bulletin served to inform licensees of recent HFA relay failures.
Additionally, the bulletin asked licensees to inform the NRC of plans, in-cluding schedules, for implementation of General Electric's (GE) recommenda-tions that are discussed in several GE Service Advice Letters (SAL) and Ser-vice Information Letters (SILs) issued in 1980 and 1982. This bulletin also requested licensees to submit information concerning plans to upgrade sur-veillance and to justify continued operation until the above GE recommenda-tions are implemented.
Accordingly, please find attached the District's response to IE Bulletin 84-02 including plans and schedules of the bulletin, the schedule for imple-mention, additional information concerning an upgrade of surveillance and justification for the continued safe operation of Fort Calhoun Station until completion of the required actions.
IE Bulletin 84-02 also stated that it would be helpful to the NRC in evalu-ating the cost of this bulletin to provide the time the District spent to perform the requested review and prepare requested documentation. The Dis-8509220380 050717 PDR ADOCK 05000285 G
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4ssu4 Emploumentgngua opportunity
Mr. J. T. Collins July 17,1984 p
trict utilized approximately 360 manhours in review for and preparation of -
this response.
Sip drely, d
&!h R. L. Andrews Division Manager RLA/DJM/rh-A Attachment cc:
U.S. NRC Document Control Desk l
LeBoeuf, Lamb, Leiby & MacRae I
1333 New Hamshire Avenue, N.W.
Washington D.C.
20036 i
Mr. E. G. Tourigny, NRC Project Manager Mr. L. A. Yandell, Senior Resident Inspector f
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y-UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION In the Matter of
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Omaha Public Power District
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Docket No. 50-285 (Fort Calhoun Station,
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Unit No.1)
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...... being duly sworn, hereby deposes and says that he is Division Man-ager - Nuclear Production Division of Omaha Public Power District; that he is duly authorized to sign and file with the Nuclear Regulatory Commission the attached response to IE Bulletin 84-02; that he is familiar with the content thereof; and that the matters set forth therein are true and correct to the best of his knowledge, infomation and belief.
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R. L. Andrews Division Manager Nuclear Production STATE OF NEBRASKA)) ss COUNTY OF DOUGLAS)
Subscribed and sworn to before me, a Notary Public in and for the State of Nebraska on this 17th day of July,1984.
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r Attachment Response to IE Bulletin 84-02 Request 1.
Plants in Operation a.
Develop plans and schedules for replacing (1) nylon or Lexan coil spool-type HFA relays used in normally energized safety-related*
applications and (2) nylon coil spool-type HFA relays used in normally de-energized safety-related applications. The replace-ment program for energized and de-energized relays should be per-formed on a "best efforts" basis during plant outages of suffi-cient duration. The entire replacement program should be com-pleted within two years from the date of this bulletin..
The replacement schedule should consider the followins, recommend-ed priority:
Nylon or Lexan nonnally energized in the reactor trip system Nylon or Lexan normally energized in other safety-related appli-cations Nylon normally de-energized in the reactor trip system Nylon normally de-energized in other safety-related applications District Response The District will replace all safety-related HFA relays described in la above prior to March 1986.
The replacement. schedule will generally follow the above recommended priority list.
Request b.
During the period before relay replacement, develop and implement surveillance plans that include:
(1)
Monthly functional tests of all reactor trip system norm-ally energized relays that verify relay contacts change state when the relay coil is de-energized; (2)
Visual inspections of all safety-related normally energized relays as soon as practical upon receipt of this bulletin.
Thereafter, similar inspections should be accomplished in conjunction with the monthly functional test. These visual inspections should verify that relay coils are not deterior-ating (e.g., inspect coil bobbins for visible cracks or melting), and should confirm cleanliness of the relay pole pieces.
- For the purpose of the. applicable actions of this bulletin, " safety-related" constitutes those systems covered by the definition given in 10 CFR Part 100, Appendix A Sections III.(c)(1), III.(c)(2), and III.(c)(3).
In assessing the impact of Lexan/Kylon coil spool-type HFA relay in other. systems at their facilities, licensees should consider the provisions of GDC 1 to 10 CFR Part 50, Appendix A.
r District R?sponse The District-does not_ presently use HFA relays on the reactor trip system. Therefore, no additional monthly functional tests are required. For the balance of the Fort Calhoun Station, HFA relays in other systems are tested on a monthly basis in cases a
where design basis is such that montnly tests are practical. An example of such tests are the Ventilation Isolation Relays. The visual inspection, referenced above, is believed to be adequate for those relays not tested monthly (for example, the containment isolation relays). The District has conducted a visual inspec-tion as requested by the Bulletin.
The results of this visual i
inspection indicate that the HFA relys do not appear to be de-teriorating. Visual inspections will be conducted on a monthly basis.beginning in July and continuing until the relay replace-ment can be completed to reconfirm the results of the initial visual inspection.
Request c.
Provide a basis for continuing operation for the period of time until the normally energized relays are replaced. This basis should include a discussion on those measures addressed in Items la and Ib and any other preventive and/or corrective measures taken or planned.
District Resporse OPPD's operating experience with HFA relays has been very good.
A review of approximately 200 electrical equipment related maintenance orders to determine those concerning HFA relays has been conducted. The results of those maintenance orders reviewed indicated that, of approximately 260 HFA relays in use at Fort Calhoun Station, one relay had a singe crack in the spool piece and was subsequently repaired. This rel Ay was found during a November 1981 inspection.
It.should be noted that the relay was totally operational.
l OPPD's experience with HFA relays in similar applications in fos-sil units and substations has also been very good. HFA relays in these applications have.been in use for periods of time that ex-ceed that of Fort Calhoun Statio'n operation.
Based on discus-sions held with fossil plant and substation personnel, failures of HFA relays have not significantly increased with age for fos-sil units and substation applications. Failures of HFA relays l
beyond random failure (accounted for in redundant design) are not expected before the replacement is completed.
Also, HFA relays'are not utilized in the Reactor Trip System at Fort Calhoun Station.
i Operating experience and reliability, coupled with redundancy and monthly visual inspections until replacement, combine to provide reasonable assurance that continued operations of the l
Fort Calhoun Station will not impact the health and safety of l
the public and is, therefore, justified.
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4tequest 4.
If your plant uses or plans to continue to use the nylon or Lexan-type HFA relay in systems other than those safety-related applica-tions defined in this bulletin, then the appropriate administra-tive controls dealing with maintenance, storage, and handling of spare parts at your facility must be revised.to ensure that the older and problematic HFA relay coils are not inadvertently used 1
as a replacement part in safety-related applications in future maintenance efforts at your facility.
District Response OPPD will implement a progran by August 15, 1984, whereby only qualified HFA relay parts will be stocked in the Fort Calhoun Sta-tion storeroom. As these qualified replacement parts will fit both types of HFA relays, (the safety-related and qualified re-lays, and the non-safety-related unqualified relays), this will preclude the possibility of mishandling the older unqualified relay parts.
Additionally, the bulletin contains a request for rel Ay infonna-tion of a generic nature. Specifically:
"Although the specific details involving the iden-tified relay failures described above may not directly apply to your facility (fes), you are asked to review the general concerns expressed in the bulletin for applicability at your facil-ity(ies). For example, if a different type of relay is used for the same safety functions des-cribed in this bulletin, or relays with similar materials are used for other safety-related functions, past operating history and the man-ufacturer's recommendations should be reviewed to determine if additional action is appropriate.
Your response should describe the results of the review, and, if the general concerns apply, you j
should describe the short-tenn and long-tenn cor-rective actions to be taken and the schedules thereof".
The District has conducted a preliminary review of the operating history of other relays in use at the Fort Calhoun Station. The review included a review of the LER's submitted from 1976 to l
1983.
l As a result of this preliminary review, the District is planning to conduct an additional investigation of the "86 lockout" re-1 ays. The District plans to conduct this additional investiga-l tion during the upcoming months.
The District will evaluate the I
results of the above mentioned investigation and take the neces-sary action.
Also, the District has contacted the vendors of relays in use at Fort Calhoun Station to detennine if any aging i
or lifetime data exists. The District believes that participa-tion in such programs as NPRDS and vendor interface will lead to early identification and resolution of equipment problems.
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The District also believes that equipment installed at the Fort Calhoun Station is reliable, and suitable for its intended ser-vice. The USAR and related documents provide for this adequacy.
In addition, the District believes that this has been substan-tiated by an excellent operating history. Programs such as 1
surveillance testing, preventive maintenance, equipment history, NPRDS, etc., will ensure safe operation.
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