ML20137H351

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Forwards IE Circular 76-03, Radiation Exposures in Reactor Cavities. Prompt Reply Requested.Original Submittal Forwarded on 760913 Not Received as Noted on 761214
ML20137H351
Person / Time
Site: Dow Chemical Company, 05000000
Issue date: 12/17/1976
From: James Keppler
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To: Langner R
DOW CHEMICAL CO.
Shared Package
ML20136D183 List: ... further results
References
FOIA-85-256, FOIA-85-258, FOIA-85-259, FOIA-85-261 IEC-76-03, IEC-76-3, NUDOCS 8508290019
Download: ML20137H351 (1)
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DEC 171976 The Dow Chemical Company Docket No. 50-264 ATTN: Dr. R. R. Langner

, Chaireen Radiation e

Safety Cossaittee 1803 Building Midlande Miehisen 4R640 Centlemen:

On September 13, 1976, we mailed to you a copy of Circular No.76-03e which required a reply within airty days. On December 14, 1976, we learned that the aircular.had never been reesived. N refora we are enclosing a copy of the e

cireulare to which we woeld appreciate a prompt reply.

Sincerely yours, James C. reppler Regional Director Taelosure:

IK Circular No. 76-03 as w/enel:

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OFFICE OF 11:SI'ECT10 A!;U 1::1 FORCE!!EIIT WASill!E10ii D. C. 20555 In Circular 1:o. 76 - 03 DATE: September 13, 1976-RADIATIO'1 EXPOSURES IN REACTOR CAVITIES DESCRIPTION OF CIRCUMSTANCES:

On !! arch 18, 1976, an employee at the Zion station received a "whole body" radiation dose of 8 rems or more upon entering the cavity bcncath the reactor vessel during a refueling out-age. On April 5, 1976, a sfullar reactor cavity entry at Indian' Point resulted in a 10-rem uhole body dose to a licen-sec employec. A similar entry on October 5, 1972 cauced a 5-rem dose to a Polnt Beach cr.pJoyce.

Thece three overexposurcs appear to have been caused by failure to appropriately control entry into high radiation arecs, failure to conduct cdequate surveys and inilure to compensate for expo-sure rate variations that can occur in various arcas in pouer reactors, e.g., the cavity bcncath the reactor veccel. With the incore thinblec and detectors inserted into the core, radiation Icvels in the cavity appear to be low. With the thimbics or detectors uithdraur into the cavity, however, exposure rates of hundreds or=possibly thousands of roentgens per hour con exist.

Overexposurcs can occur in seconds.

All three overexposure events involved entry into potentially high radiation areas without surveys and/or special controls over equipment which could cause trancients in the exposure rato.

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IE Ciren]ar ro. 76 - 03 Date: September 13, 1976 ACTIO!! TO 1;E TAKlai llY LICEllSF.ES:

While the three exposures above occurred at pressurized water reactors, similar nituations could develop at other types of reactorn, e.g., pneumatic irradiation equipuent arean (research reactorc) and traveling incore probe equipt.:ent areas (boiling water reactors). According]y, holders of power, tect and research reactor operating licenses are to complete the followin;p

1. Perform a thorough review of plant areas and operations to identify high radiation areas, both continuous and transient, as defined in 10 CFR 20.202(b).
2. Verify that entryuays into high radiation areas are con-spicuously posted and locked or otheruise controlled in such a manner as to explicitly identify the nature of the hasard, appropriately control entry, and require adequate pre-entry surveys, ,
3. Ensure that radiation protection procedures and radiation protection training and retraining programs specifically addresa the matter of control of and access to cich areas and initiate cppropriate retraining of all plant personnel,
4. Ensure that the procedures governing personnci entry into all actual or potential high radiation areas pcrnit such entry only after appropriate management review and approval so that conditions within the area arc kno en and not subject to change while the area is occupied,
5. Periodically audit whatever controls result from iten 1-4, above, to ensure their continued effectiveness, and

! 6. Confirm by written reply within 60 days that the actions for items 1-4 above, have been or are being taken. A record, detailing findings, actions tahen, and actions to be taken, nhould be retajaed for revicu by NRC during the l

next radiological safety inspectfun.

Thin request for infornation was approved by CAO under a blanhet l cicarance number 15-180225 (R0072); this clearance expires July 31, 1977.

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