ML16340A790
| ML16340A790 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 02/06/1980 |
| From: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | Crane P PACIFIC GAS & ELECTRIC CO. |
| References | |
| NUDOCS 8002210299 | |
| Download: ML16340A790 (8) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION REGION V 1990 N. CALIFORNIABOULEVARD SUITE 202, WALNUTCREEK PLAZA WALNUTCREEK, CALIFORNIA94596 February 6,
1980 Docket Hos.
50-275, 50-323 Pacific Gas and Electric Company 77 Beale Street San Francisco, California 94106 Attention:
Hr. Philip A. Crane, Jr.
Assistant General Counsel Gentlemen:
Enclosed is IE Bulletin No. 80-03, which requires action by you with regard to your reactor facility with an operating license or a construction permit.
Should you have questions regarding this Bulletin or the actions required of you, please contact this office.
Sincerely, R.
H. Engelken Director
Enclosures:
1.
IE Bulletin Ho. 80-03 2.
List of Recently Issued IE Bulletins cc w/enclosures:
E.
B. Langley, Jr.,
PGIl.E M. Raymond, PGPE R.
- Ramsay, PGSE, Diablo Canyon
SSIHS No.:
6820 UNITED STATES Accessions Ho.:
NUCLEAP, REGULATORY COlBISSION 7912190669 OFFICE OF INSPECTION AHD ENFORCE!1ENT WASHIHGTO"I, D.C.
20555 February 6, 1980 IE Bulletin No. 80-03 LOSS OF CHARCOAL FRO~i STANDARD TYPE II, 2 INCH, TRAY ADSORBE~
CELLS Description of Circumstances:
During preliminary leak tests of charcoal adsorber cells in certain ventilation svstems at Sequoyah Nuclear Plant, it was determined that on certain adsorber cells the spacing between rivets securing the perforated screen to the casing v!as too great to ensure adequate contact between the casing and the screen, thus allowing charcoal to escape.
The problem was discovered when a visual inspection detected loose charcoal on the floor of the filter housings and on the outs'ide horizontal su~faces of the adsorber cells.
Loss of charcoal was also indicated by observation of liqht penetrating through the cells.
Additional inspection revealed that the rivets securing the oerforated screens to the cell casing were anproximately six inches apart and the screen appeared to be sagging away from the casing between rivets.
The particular adsorber cells being tested at Sequoyah Nuclear Plant were Flanders Type II pre-1974 fabrication.
There is a possibility that design of adsorber cells with wide spacing between screen, rivets may pass initial freon leak tests but degrade significantly during operation thus reducing the margin of safety during postulated accidents.
The responses from this Bulletin will be used by the NRC to evaluate need for more requent insoection/testing.
For all power reactor facilities with an Operating License:
1.
Determine if charcoal adsorber cells in use, or nronosed for use, have the potential for a loss of charcoal incidental to handlinq, storaqe or use (as aopropriate).
Particular attention should be directed to examina-tion of a) rivet spacing resulting in separation of screen and'ell housing and b) adsorber cell or filter housing deformation causino loss of charcoal and/or channelinq.
Either of these items could result in a deqraded filtration system incapable of performing its intended function.
The preferred method of this determination is a visual inspection of the filter housing and adsorber cells as described in Section 5 of AViSI H510-1975.
If this method is not feasible, state in the report required by Paragraph 4 how the determination was made.
2.
For ESF filtration systems, any identified defective cells shall be replaced and the operability of the system (after cell replacement)
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IE Bulletin No. 80-03 February 6, 1980 Page 2 of 2 demonstrated by leak testing within 7 days.
Preferred method of leak testing is as described in Reaulatory Guide 1.52 and Section 12 of ANSI N510-1975.
3.
For normal ventilation exhaust filtration sjstems which employ charcoal adsorber cells and for which radioactive removal efficiency has been assumed in-determining compliance with the "as low as reasonably achievable" design criteria of 1'3 CFR 50, Aooendix I, any identified defective cells shall be replaced as soon as oossible but at least within 30 days.
After replacement, the system should be demonstrated operable by leak testing within an additional 30 days.
Preferred method of testina is as described in Regulatory Guide 1.140 and Section 12 of ANSI N510-1975.
4.
Report in Iriting within 45 days of the date of this Bulletin the results of the determination required by Paragraph 1.
The report shall include the tyoe of cells employed (manufacturer and cell desian),
system containing the cells, observed cell condition (degradation/saggina) and a discussion of visual inspection procedure and results.
For all Power Reactor Facilities with a Construction Permit:
1.
Yisual inspection shall be conducted only if the charcoal adsorber cells have been purchased and shipment received.
A representative number (approximately
- 5) of each tvoe of cell desian/manufacturer shall be visually inspected for such deficiencies as rivet spacing and screen/casing separation which could lead to loss of charcoal incidental-to handling,
- storage, or use.
2.
Report in writing within 45 days of the date of this Bulletin the results of the inspection required by Paragraoh 1.
The report shall include the type of cells (manufacturer and cell design),
observed cell condition (degradation/sagging) and a discussion of the inspection procedure and results.
Reports shall be sent to-the Director of the approoriate HRC Regional Office listed in Appendix 0 of 10 CFR 20 with a cooy of the Director, Division of Fuel Facility and Materials Safety Inspection, Office of Inspection and Fnforcement, USNRC, Mashington, D.C.
20555.
Approved by GAO, B180225(R0072);
clearance
- expires, 7/31/80.
Aporoval was given under a blanket clearance specifically for Mentified aeneric problems.
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IE Bulletin No. 80-03 February 6, 1980 PECEHTLY ISSUED IE BULLETIHS Encl osure Bul le tin Ilo.
Subject Date Issued Issued To 80-02 80-01 Inadequate Auality Assurance for Huclear Operability of ADS Valve Pneuvztic Supply 1/21/80 1/11/80 All BlIR licenses with a
CP or OL All BlfR Dower reactor facilities with and OL 79-01B Environmental Oualification 1/14/80 of Class IE Equipment All oower reactor facilities with an OL 79-28 79-27 79-26 Possible l1al function of Namco tlodel EA 180 Limit Switches at Elevated Temperatures Loss Of Hon-Class-1-E Instrumentation and Control Power System Bus During Operation Boron Loss From Bl<R Control Blades 12/7/79 11/30/79 11/20/79 All power reactor facilities with an OL or a CP All oower reactor facilities holding OLs and to those nearing licensing All BHR power reactor facilities with an OL 79-25 Fail ures of Mestinghouse 11/2/79 BFD Relays In Safety-Related Systems All power reactor facilities with an OL or CP 79-17 (Rev.
1) 79-24 79-23 Pipe Cracks In Stagnant Borated Mater System At P!IR Plants Frozen Lines Pntential Failure of Emergency Diesel Generator Field Exciter Transformer 10/29/79 9/27/79 9/12/79 All PMR's with an OL and for information to other power reactors All nower reactor facilities which have either OLs or Cps and are in the late stage of construction All Power Reactor Facilities with an Operatinq License or a construction permit
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