ML20037B382

From kanterella
Jump to navigation Jump to search
ForwardsBulletin 73-06, Inadvertent Criticality in Bwr. Action Required
ML20037B382
Person / Time
Site: Dresden, Quad Cities  
Issue date: 11/27/1973
From: James Keppler
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To: Brian Lee
COMMONWEALTH EDISON CO.
References
NUDOCS 8009240818
Download: ML20037B382 (1)


Text

-

3,

_~

'. /

ove UNITED STATES y, i ATOMIC ENERGY COMMISSION

.(

e

\\ T DIRECTORATE OF REGULATORY OPERATIONS

  1. rts o' /'

/

REGION lil 4

799 ROOSEVELT ROAD mag GLEN ELLYN ILLINOIS 60127 0 12) 858 2660 November 27, 1973 j

Cosmonwealth Edison Company n.,1 rats No. 50-10 ATTN Mr. Dyron Lee, Jr.

50-237 Vise Freefdent 50-249 F. O. Ben 767 50-254 Chisaan, 7114meis 60690 50-265

)

Gentlemen:

The amalaced Direeterate of Eagalatory Operstians Rg11atin No. 73-6, "Imedvertent Critimality in a Boillag Water Emmeter," is esat to you to provide yes with informaties that uma reported

  • to the AEC by the Vermont Yankee Euclear Power Corperation concerning an inadvertent criticality i

1 i==tJent that was experienced in the Vermont Yankae facility. This I

information any have direct applicability to your facilities. Action i

requested on your part is identified in Section A of the enclosed bulletin.

Very truly yours, 1

James G. Keppler Regional Director emelaeare:

ED 1hullegig Be, 73-6 bec: RO Files DR Central Files l

ER Local POR

  • Lar dtd 11-4-73 to Direstorata of Regulatory Operations, Engica I, King of Prussia, Fa.
  • Lar dtd 11-14-73 to Direeterate of Licensing, USAEC, liashington, D.C.

l f

M 8009240 O f gD g

k gk., Y. N _ d l

on o

)

K...,

November 27, 1973 Directorate of Regulatory Operations Bulletin No. 73-6 INADVERTENT CRITICALITY IN A BOILING WATER REACTOR We recently received an abnormal occurrence report from the Vermont Yankee Nuclear Power Corporation relating to an inadvertent criticality incident that was experienced at their Vermont Yankee facility. A copy I

of this report is being sent to you under separate cover to provide you l

with pertinent details of this event.

4 At the time of the inadvertent criticality incident, the reactor vessel and primary containment heads were removed, the refueling cavity above j

the reactor vessel was flooded, control rod friction tests were in progress, the rod worth minimizer was bypassed, and core verification had been in progress. As a result of the incident, no measurable radioactivity was released, no fuel damage resulted and no personnel exposures were experienced. The incident is currently under review and evaluation by the Regulatory Staff.

Action requested by this bulletin is contained in Section A.

1 A.

Action Requested by Licensees l

In light of this occurrence you are requested to take the following I

actions. Upon completion of these actions you are requested to inform this office in-writing, within 45 days of the date of this letter, of the status of each item identified in each paragraph and subparagraph listed below:

4 1.

Procedural Review j

)

a.

Control Rod Drive Operating and Testing Procedures (1) Conduct a review of your control rod drive operating and testing procedures to determine that approved procedures exist for all operations and tests.

1 i

(2) Verify that appropriate prerequisites are included in the procedures to require testing of associated inter-locking and protection features before control rod i

testing is permitted.

i (3) Assure that prerequisites and detailed instructions are l

provided that demonstrate compliance with technical specification requirements and design bases.

p MI/! 3@s f@

t

3

, b.

Bypass Installation Procedures (Jumoers or Lifting of Leads)

Assure that existing bypass installation procedures have been conservatively reviewed for technical adequacy and for adminis-strative controls.

c.

Radiation Protection Procedures f

Assure that procedures for access control and personnel accountability in areas subject to accidents are current.

d.

Shift Transition Procedure (Turnover)

Assure that complete and detailed procedures are in effect that provide instructions for a proper and conservative turnover of shift responsibilities.

Such procedures must j,

include requirements for ccumunicating the status of all i

safety related equipment and conditions.

i 2.

Management Controls i

Assure that your management contr'ols that are in effect provide for

~

qualified technical and administrative reviews and approvals of temporary circuitry changes and temporary off-normal plant conditions.

This review should assure that the responsibilities and requirements I

associated with the review and approval, installation, verification, removal, and subsequent testing of temporary circuitry changes and i

temporary off-normal plant conditions are clearly delineated in station procedures, are understood by the station staff, and are being properly implemented.

3.

Licensed Operator Performance Assure that management provides the necessary opportunities and time so that operators are adequately trained to carry out their assigned responsibilities.

In particular, confirm that shift crew members are provided special training for safety related activities that are infrequent, complex, or have unusual safety significance.

If you have any questions concerning this request, please contact this office.

Enclosure:

A0 No. 7331 - Ltr dtd 11/14/73 (separate cover) e e.

.