ML19257C094

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Forwards IE Info Notice 79-33, Improper Closure of Primary Containment Equipment Access Hatches. No Action or Response Required
ML19257C094
Person / Time
Site: Summer South Carolina Electric & Gas Company icon.png
Issue date: 12/21/1979
From: James O'Reilly
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To: Nichols T
SOUTH CAROLINA ELECTRIC & GAS CO.
References
NUDOCS 8001240131
Download: ML19257C094 (1)


Text

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101 MARIETTA ST N.W.. SUITE 3100 ATLANTA. GEORGIA 30303 In Reply Refer To:

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DEC 211975 South Carolina Electric and Gas Company Attn:

T. C. Nichols, Jr., Vice President Power Production and System Operations Post Office Box 764 Columbia, South Carolina 29218 Gentlemen:

This Information Notice is provided as an early notification of a possibly significant matter.

It is expected that recipients will review the Information for possible applicability to their facilities. No specific action or response is requested at this time.

However, we anticipate that further NRC evaluations will result in issuance of an IE Circular or Bulletin in the near future which will recommend or request specific applicant or licensee actions.

If you have questions regarding the matter, please contact the Director of the appropriate NRC Regional Office.

's Sincerely,

~

James P. O'Reilly Director

Enclosures:

1.

IE Information Notice No. 79-33 2.

List of Recently Issued Information Notices 1804 249 sooledo 13 /

UNITED STATES SSINS No.:

6870 NUCLEAR REGULATORY COMMISSION Accession No.:

OFFICE OF INSPECTION AND ENFORCEMENT 7910250520 WASHINGTON, D.C.

20555 qn December 21, 1979 IE Information Notice No. 79-33 IMPROPER 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 containment 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 I and is reinspecting these hatches on Unit 3.

It is anticipated that further NRC evaluatiori vill result in issuance of an IE Circular or Bulletin in the near future which will recommend or request specific applicant or licensee actions.

This information is provided to inform licensees of a possibly significant matter.

The improper closure of the primary containment access hatches resulted from a lack of procedures for torque values, sequence of torque, and alignment 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 Information Notice is required.

1804 250

IE Information Notice No. 79-33 Enclosure December 21, 1979 RECENTLY ISSUED IE INFORMATION NOTICES Information Subject Date Issued To Notice No.

Issued 79-33 Improper Closure of Primary 12/21/79 All holders of power reactor Containment Equipment Access OLs and cps Hatches 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 power reactor facilities Response Spectra (ARS) holding OLs and cps 79-30 Reporting of Defects and 12/6/79 All power reactor facilities Noncompliances, 10 CFR holding OLs and cps and Part 21 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 1804 251