ML20153D812
| ML20153D812 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 02/13/1986 |
| From: | Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | Harold Denton, Rubenstein L Office of Nuclear Reactor Regulation |
| References | |
| 86-042, 86-42, NUDOCS 8602240258 | |
| Download: ML20153D812 (2) | |
Text
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6 VINGINIA ELECTRIC AND Powsu COMI%NY Ricnxoxn,VINGINIA 202G1 W.L.StawamT l
32"j'o'['",3,,,
February 13, 1986 Mr. Harold R. Denton,l.irector Serial No.86-042 Office of Nuclear Reactor Regulatio".
N0/DAS/aca Attn: Mr. Lester S. Rubenstein, Director Docket Nos. 50-338 PWR Project Directorate #2 50-339 Division of PWR Licensing-A License Nos. NPF-4 U.S. Nuclear Regulatory Commission FPF-7 Washington, D.C. 20555.
Gentlemen:
VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS NO. 1 AND 2 REACTOR COOLANT SYSTEM THERMAL SLEEVES AND CONTROL ROD OPERABILITY TESTING Virginia Electric and Power Company letter, Serial No. 460, dated August 4, 1982, for North Anna Unit No. 2, committed to a program of increased surveillance to address the potential concerns of loose parts in the reactor coolant system as a result of degraded thermal sleeves. One of the commitments was to perform, on a weekly basis, control rod exercises to verify the free movement of the control rod assemblies.
This commitment was also made for North Anna Unit No.1, in our letter, Serial No.
574, of October 12, 1982, and was subsequently affirmed in an NRC Safety Evaluation (SE), dated Januery 11, 1983, that detailed our proposed corrective actions and justification for continued operatien.
The commitment is in excess of the related technical specification requirement which calls for surveillance testing every 31 days.
The Westinghouse Safety Evaluat.on attached to our August 4, 1982 and October 12, -1982 correspondence evaluated the effect of loose thermal sleeves on reactor internals. In that analysis, Westinghouse stated, "In the unlikely event that a foreign object would become lodged in the upper package during operation and cause a drivelino to become inoperable, the existing FSAR analyses assumption of one stuck control rod asse. ably would not be exceeded." The commitment for increased frequency testing of control rod assemblies was provided in the augmented surveillance program as additional operational assurance that the then observed thermal sleeve cracking would not affect continued safe operation in the immediate future. To date there have been no indications that a continuing problem exists with thermal sleeves. The remaining thermal sleeves in the Unit 1 and 2 reactor coolant system were inspected by radiographic inspection techniquet during the last refueling cutages and the espection results did not indicate any significant flaws in the thermal si. eve tack welds or rissing thermal sleeves.
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'b vano:xtA Ex.actate Ann Powan ComeAxy to Mr. Ilarold R. Denton We believe that the ' increased frequency testing of movable control rod assemblies is no longer necessary and only increases the risk of undesirable transients (such as turbine runback). It is our intention to revert to a test frequency of at least once every 31 days per Technical Specification 3/4.1.3 as of April 1, 1986. If you have any questions regarding our deletion of this additional testing commitment, please do not hesitate to contact us.
Very truly yours,
)
w L
W. L. St'ewart ec:
Dr. J. Nelson Grace Regional Administrator NRC Region II Mr. M. W. Branch h1C Resident Inspector North Anna Power Station Mr. Leon B. Engle NRC Nor.d 8vna Project Manager 4
PWR Pr.) ject Directorate #2 Div2tien of PWR Licensing-A i
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