ML20134H236
| ML20134H236 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 08/07/1985 |
| From: | Opeka J, Sears C NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES |
| To: | Murley T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| (SD-67), F0766A, F766A, NUDOCS 8508280329 | |
| Download: ML20134H236 (2) | |
Text
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NORTDMAST UTILITIES o.n.,.i Ome... seio n si,..i. e.,iin. conn.cticui l
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P.O. BOX 270 HARTFORD. CONNECTICUT 06141-0270 k
k J C,)$$[E.2,~cd (203) 665-5000 August 7,1985 Docket No. 50-423 F0766A Dr. Thomas E. Murley Regional Administrator U. S. Nuclear Regulatory Commission Region 1 631 Park Avenue King of Prussia, PA 19406
References:
(1)
W.
G. Counsil letter to T. E. Murley, F0658A, dated January 11,1985.
(2)
W.
G. Counsil letter to T. E. Murley, F0713A, dated March 14,1985.
(3) 3.
F.
Opeka letter to T.
E.
Murley, F0720A, dated May 2,1985.
Dear Dr. Murley:
Millstone Nuclear Power Station, Unit No. 3 Reporting of Potential Significant Deficiencies in Accordance with 10CFR50.55(e):
Improper installation of Conduit Seal for Rosemount Pressure Transmitters (SD-67)
In a December 14, 1984 telephone conversation between your Mr. T..Rebelowski and our Mr. R. E. Lefebvre, Northeast Nuclear Energy Company (NNECO) reported a potential significant deficiency (PSD) in the construction of Millstone Unit No. 3 in accordance with 10C FR 50.55(e).
The potential significant deficiency involved Rosemount differential pressure transmitters with improper conduit installations as described in Reference (1).
Reference (2) reported that NNECO had determined that all Rosemount transmitters utilizing Litton Yeam connectors were installed without a conduit thread scalant (grafoil tape) which is necessary to prevent moisture from accumulating in the terminal side of the transmitter housing during accident conditions.
Additionally, an investigation by our architect-engineer, Stone & Webster Engiacering Corporation, (SWEC) revealed that this can be attributed to the long time duration between the installation of the Rosemount transmitters and the procurement of the Litton Yeam connectors.
8508280329 850007 PDR ADOCK 05000423' t j PDR S
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As stated in Reference (3), NNECO has determined the improper installation of the conduit seals on the Rosemount transmitters to be a significant deficiency in the construction of Millstone Unit No. 3.
All Rosemount transmitters utilizing a Litton Yeam Connector will be reworked by NNECO and Grafoil Tape will be applied as a thread sealant. In addition, an evaluation performed to determine whether or not a thread sealant is required on other instrument installations has revealed no further problems to date. Since the results of this evaluation have no affect on this deficiency, the above information should be sufficient to allow SD-67 to be closed.
If NNECO identifies a potential problem with any of the remaining instrument installations, a new PSD will be evaluated.
As such, we consider this to be our final report for SD-67. We trust that the above information satisfactorily responds to your concerns.
Very truly yours, NORTHEAST NUCLEAR ENERGY COMPANY b.b. D WL
- 3. F. Opeka ~
Senior Vice President By: C. F. Sears Vice President cc:
Division of Inspection and Enforcement U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Mr. 3. M. Taylor, Director
.