ML20084N669

Ro:On 751008,portable Fuel Loading Chamber Containing 2 G SNM Declared Lost.Caused by Lack of Proper Storage.Rev of Nuclear Procedures Will Be Initiated

ML20084N669
Person / Time
Site:	Dresden
Issue date:	10/17/1975
From:	Stephenson B COMMONWEALTH EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
699-75, NUDOCS 8306080418
Download: ML20084N669 (3)

Text

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- Chicago Illinois 60690 50 249

'BBS LTR #699-75 Dresden Nuclear Power Station R. R 61 Morris, Illinois. 60450 October 17, 1975

/o Mr. James G. Keppler, Regional Director [;

Directorate of Regulatory Operation-Region III (./

, U. S. Nuclear Regulatory Cor:nission, , fy 799 Roosevelt Road Glen Ellyn, Illinois 60137

SUBJECT:

REPORT OF LOSS OF SPECIAL NUCLEAR IMTERIAL IN ACCORDU!CE WITE 10CFR 70.52

References:

1) Title 10 of Code of Federal Regulations part 70 section 70 52 (a)

2) Notification of Region III of U. S. Nuclear Regulatory Comission Oral: Vr. P. Johnson, 1100 hours0.0127 days <br />0.306 hours <br />0.00182 weeks <br />4.1855e-4 months <br /> on October 8, 1975 Report Date: October 17, 1975 Occurrence Date: October 8, 1975 Facility: Dresden Nuclear Power Station, Morris, Illinois IDENTIFICATION OF OCCURRECE On October 8,1975, a portable Fuel Loading Chamber (FLC) containing two grams of Special Nuclear Material (Sh"4) was declared lost. W.e SNM was 93 355 enriched uranium - 235 CONDITIONS PRIOR TO CCCURRE!CE Unit-3 was operating at a power level of 770 MWe following the unit's third partial refueling outage.

DESCRIPTION OF OCCURREJCE On April 18, 1975, five FI4's were sent from Quad Cities Nuclear Fower Station to Dresden. The FIf's were packaged in the following manner:

Three clean FLC's were loaded into one 55-gallon drum; two contaminated FLC's were loaded in a second 55-callon drum. Two FLC's in each drum were sent with 8306080418 751017

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. U V associated cables attached to then. The fifth FIE (a clean spare) was put into a plastic bag, wrapped in rags, and placed in the bottom of the drun containing the other two clean' FIC's. Both drums were bolted closed.

The FLC's were received at Dresden on April 18, 1975 On April 19 the two drums Were transferred to the refueling floor of the reactor building and stored on top of the Unit 2/3 new fuel vault until April 27, 1975 On April 27, two instrument mechanics (IM's) opened the drums containing the FIC's and inspected the dru=s' contents. The IM's noted the presence of the four FIC's with cables and the fifth FIE wrapped in rags before leaving the area.

On April 28, three IM's were sent to inspect the FID's prior to installation in the reactor. The IM's unloaded the four FIE's with cables attached but did not look for a fifth FIE. After the four FIE's had been removed, the two 55-gallon

, drums were stored on the south wall of th,e Unit-3 refueling floor, between the reactor head storage area and the Unit-3 fuel pool.

From April 27 to August 6,1975, major activities on the refueling floor included out-of-core sipping, feedwater sparger replacement, and local power range monitor replacement.

On August 6,1975, as preparations for fuel reloading of Unit-3 were being made, the spare FIE was noted to be missing by the fuel handling foreacn. The nuclear materials custodian and assistant superintendent were notified, and a search was made of the reactor building, with negative results. Further searching was postponed until after completion of the Unit-3 fuel loading since fuel handlers were conducting the search.

Extensive searches of the Unit 2/3 reactor building were conducted from August 26 to September 1, again without success. The refueling of Unit-1 in addition to fuel handler personnel radiation exposure problems necessitated delays in the searching schedule. During these delays, drum movements out of the reactor building were restricted.

On October 7 and 8 a complete and thorough search was made of the ' reactor building, again with negative results. On Cetober 8 at 1000 hours0.0116 days <br />0.278 hours <br />0.00165 weeks <br />3.805e-4 months <br />, the missing FIL was declared lost. Notifications of the loss, i*ncluding an oral report to NRC Region III Inspector P. Johnson who was on-site, were made immediately. -

DESIGNATION OF APPARET CAUSE OF OCCURRENCE The primary cause of the occurrence was the lack of proper storage for the FIE's.

Although there is a special storage area set aside for nuclear fuel, special storage is not provided for components which contain small but reportable amounts of uranium. A lack of administrative controls for the packaging, movement, and storage of FID's was a contributing cause of this occurrence. Commonwealth Edison Nuclear Procedures do not address the problem of handling small, reportable amounts of Special Nuclear Materials.

ANALYSTS OF OCCURRENCE During the period from April 27 to August 6, the only operation involving the use of a cut:stantial number of 55-gallon drums was the feedwater sparger replacement job. The dru.'is were used'for the disposal.of' dry active. waste (DAW) resulting from

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, the job, and for stor:gn of contaminated toolo. Drums containing DAW were sent to the Un.t 2/3 radwaste barreling area and were eventually transported to Sheffield, Illinois for burial. Drums used for tool storage were thoroughly inspected without success; however, one of the two FIL shipnent drums was discovered during this inspection.

Therefore, it is cons'idered highly probable that either the missing FIf is buried with waste at Sheffield, or it is still on-site at some unknown location. In either case, the consequences to the safety of plant personnel or the public are minimal. This conclusion is based on the following considerations:

a) the amount of uranium involved was small (2 grams); b) the uranium had not

- been irradiated and consequently had minimal activity (less than one millicurie and a dose rate of less than O.T milli-Rem / hour at contact); and c) the uranium was in a solid form, encapsulated in an air-tight container.

Finally, the possibility and significance of illegal diversion of nuclear material in the FI4 was exardned and ruled out for these reasons: 1. The amount of uranium was small, and the material was in a form which would not concern public safety as a result of illegal diversion (the uranium is coated on a capsuie which is then sealed within another capsule) 2. Only a very few management personnel of known reliability were aware that these instruments contained SGI 3 The security of Dresden station is adequate to ensure that the FIf could not easily be taken off-site in an'; form'other than radwaste 4 During the entire investigation of this occurrence, there was no hint of any conscious diversion of the FIf.

CORRECTIVE ACTICN Corrective actions to prevent a similar occurrence are listed below:

1. In the future, Dresde'n will ship FLC's only if they are properly packaged, including foam rubber for protection from jolts to the container.

2. The FIf's will be stored in the . Unit-1 fuel vault upon receipt, unless dose rates are unacceptably high; in that case, FLC's will be stored in a fuel pcol.

3 Movement of FIf's on-site will be accomplished under the same types of admin-istrative controls that govern movement of fuel assemblics.

4 FIL inventories will be made on a monthly basis.

5 A revision to CF':o nuclear proceda es will be initiated; the revision will deal with components containing small but reportable amounts of SNM.

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