ML19211C181
| ML19211C181 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 12/26/1979 |
| From: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | Arenal A SOUTHERN CALIFORNIA EDISON CO. |
| References | |
| NUDOCS 8001110033 | |
| Download: ML19211C181 (1) | |
Text
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o, UNITED STATES
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NUCLEAR REGULATORY COMMISSION s
REGION V o
1990 N. CALIFORNI A BOULEVARD
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SUITE 202, WALNUT CREE K PLAZA
+.,,a WALNUT CR EE K, CALIFORNI A 94596 December 26, 1979 Occket flos. 50-206, 50-361, 50-362 Southern California Edison Company
- p. O. Box 800 2244 Walnut Grove Avenue Rosemead, California 91770 Attention: Mr. A. Arenal, Vice president Advanced Engineering Gentlemen:
This Information flotice is provided as an early notification of a possibly significant matter.
It is expected that recipients will review the Information flotice for possible applicability to their facilities.
fio specific action or response is requested at this time.
However, we anticipate that further flRC evaluations will result in issuance of an IE Circular or Bulletin in the near future which will recommend or request specific applicant or licensee actior.s.
If you have questions regarding the matter, please contact the Director of the appropriate f1RC Regional Office.
Sincerely, m 66 h a
R. H. Engelken Direc tor -
Enclosures:
1.
IE Information flotice flo. 79-33 2.
List of Recently Issued Information Notices cc w/ enclosures:
J. M. Curran, SCE J. T. Head, SCE J. H. Drake, SCE 1737 341 s o ou 2, 933
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.g oeJ 2.d UNITED STATES SSIflS fl0.:
6870 NUCLEAR REGULATORY COMMISS10ft Accession flo.:
OFFICE OF INSPECTION AND ENFORCEf1ENT 6%
WASHINGTON, D.C.
20555
,"10250 December 21, 1979 IE Information ?!otice No. 79-33 IftPROPER CLOSURE OF PRIMARY CONTAINMENT EQUIPMENT ACCESS HATCHES Description of Circumstances:
On December 8,1979 difficulty was experienced in establishing the required nitrogen pressure in primary containnent during power range startup testing of the Browns Ferry Nuclear Plant, Unit 3, following a refueling outage. On December 9,1979, the licensee found three loose bolts on an equipment hatch to be the cause of leakage from the primary containment. The leakage was calculated to have been ten times the allowable containment leakage rate. This hatch had previously passed a local leak rate test (LLRT) and an integrated leak rate test of the containment in November 1979. The reactor had returned to operation on December 6,1979 from the refueling outage and had operated at power levels less than 25 percent since December 6,1979.
A subsequent inspection by the licensee of both primary containment equipment access hatches for Unit 2 was performed. TVA reported on December 20, 1979, to the NRC that they had found six of twelve closing dogs on one hatch improperly aligned and one closing bolt not torqued. A LLRT, performed with the hatch in this condition, showed a leakage rate higher than normal but within Technical Specification limits. The second hatch on this unit was found to have eight of twelve closing dogs improperly aligned.
The licensee is in the process of inspecting the closure of both primary contain-ment equipment access hatches on Unit 1 and is reinspectina these hatches on Unit 3.
It is anticipated that further NRC evaluation will result in issuance of an IE Circular or Bulletin in the near future which will recomend or request specific applicant or licensee actions.
This information is provided to inform licensees of a possibly significant matter.
The imoroper closure of the primary containment access hatches resulted from a lack of procedures for torque values, sequence of torque, and alignnent of the closing dogs. We expect that recipients will review the adequacy of their pro-cedures for access hatch installation at all facilities.
If installation pro-cedures do not exist or are inadequate, inspection and local leak rate testing can be used to confirm containment penetration integrity.
If you have any questions regarding this matter, please contact the Director of the appropriate NRC Regional Office.
No written response to this Infomation Notice is required.
1737 342
,IE Information Notice No. 79-33 Enclosure December 21, 1979 4
RECENTLY ISSUED IE INFORMATION NOTICES Information Subject Date Issued To Notice No.
Issued 79-32 Separation of Electrical 12/21/79 All power reactor facilities Cables for HPCI and ADS holding OLs and cps 79-31 Use of Incorrect Amplified 12/13/79 All holders of power reactor Response Spectra (ARS)
OLs and cps 79-30 Reporting of Defects and 12/6/79 All power reactor facilities Noncompliance,10 CFR Part 21.
holding OLs and cps and vendors inspected by LCVIP 79-29 Loss of NonSafety-Related 11/16/79 All power reactor facilities Reactor Coolant System holding OLs or cps Instrumentation During Operation 79-28 Overloading of Structural 11/16/79 All power reactor facilities Elements Due to Pipe Support with an OL or CP Loads 79-27 Steam Generator Tube 11/16/79 All power reactor facilities Ruptures At Two PWR holding OLs and cps Facilities79-12A Attempted Damage To New 11/9/79 All Fuel Facilities, Fuel Assemblies research reactors, and power reactors with an OL or CP 79-26 Breach of Containment 11/5/79 All power reactor facilities Integrity holding Ols and cps 79-25 Reactor Trips At Turkey 10/1/79 All power facilities with Point Units 3 And 4 an OL or a CP 79-24 Overpressurization Of 10/1/79 All power reactor facilities Containment Of A PWR Plant with a CP After A Main Steam Line Break 1737 543