ML20039C402

Proposes Modified DOE Funded Fuel Surveillance Program Workscope for FY82,per 790124 Commitment.Decision Requested by 810301.WA Graul Encl

ML20039C402
Person / Time
Site:	Fort Saint Vrain
Issue date:	12/11/1981
From:	Lee O PUBLIC SERVICE CO. OF COLORADO
To:	Novak T Office of Nuclear Reactor Regulation
References
FSV-78A, P-81322, TAC-57625, NUDOCS 8112290315
Download: ML20039C402 (5)

Text

_,

e' e

PUBLIC SERVICE COMPANY OF COLORADO P.

O. BOX 84O DENVER.

COLORADO 8020e December 11, 1981 Fort St. Vrain i

4 vic e.. es e e,"

Unit No.1 P-81322

}

7 g

FS V- )%

9 RECENED

. 9I DEC2 81981> 11 Mr. Thomas M. flovak C

pm' Assistant Director for Operating Reactors uneas suam m 9

8 Division of Licensing i

U. S. fluclear Regulatory Commission g

Washington, DC 20555 to Docket No. 50-267

Subject:

FSV Segment 2 Fuel Surveillance

Reference:

PSC letter from Mr. 0.R. Lee to Mr. T.M. Novak, P-81254, dtd flovember 16, 1981 l

Dear Mr. flovak:

In our letters of June 20, 1978 and June 23, 1978 ;P-78103 and P-78103A respectively) the DOE funded Fort St. Vrain Fuel Surveillance Program was described. The program scope includes nondestructive examination at the reactor site of five pre-characterized fuel elements from each of the initial core Segments 1-6 and a destructive post irradiation examination (PIE) in San Diego of one fuel element from Segments 1, 2, 4, and 6.

In our letter of January 24, 1979 (P-79017) PSC stated that in the event DOE funding were to be withdrawn or substantially reduced, PSC would submit a modified program workscope to NRC for approval.

Overall HTGR technology funding by DOE has been substantially reduced since 1979.

Allowing for inflation, the effective reduction in funding since 1979 has been nearly 40%.

Accordingly, funding for the FSV Fuel Surveillance Program has been reduced for FY-82, and a modification of the program is necessary.

l t0(

0 8112290315 911211

(

PDR ADOCK 03000267 P

PDR

P-81322 Page 2 December 11, 1981 1

The purpose of this letter is to present to NRC a proposed modification to the fuel surveillance workscope.

PSC requests NRC approval to eliminate the destructive PIE of the Segment 2 surveillance element.

Nondestructive examination of five Segment 2 fuel elements at the site will be carried out as originally planned.

Based upon the following infomation, PSC believes that this request is reasonable and does not compromise the intent of the FSV Fuel Surveillance Program.

1.

The results of the destructive examination of the surveillance element from initial core Segment 1 indicated that no inservice coated fuel particle failure occurred during Cycle 1 operation. This observation is consistent with the very low level of circulating activity observed in the primary circuit during Cycle 1.

Circulating activities during Cycle 2 remained equal to or less than Cycle 1 levels i

and were virtually constant throughout the cycle, indicating that no inservice failure would be observed in a PIE of Qe Segment 2 fuel.

2.

The Segment 1 surveillance element received 174 equivalent full power days (EFPD) exposure (about 10% of full design exposure).

The Segment 2 surveillance element has received only an additional 189 EFPD exposure.

Further PIE infonation at such low exposures is not expected to make a significant additional contribution to our understanding of coated fuel particle performance under normal operating conditions.

3.

Fuel Test Elements FTE-2, 4 and 6 each contain 88 FSV reference fuel rods. These test elements are currently scheduled for destructive PIE under DOE funding for the large HTGR program. The table below shows the estimated exposure (EFPD) that will be accumulated by the surveillance elements and these three FTE's.

Element Removed Estimated i

After Cycle Element EFPD Exposure I

1 SURV-1 174 3

FTE-2 489 4

SURV-4 963 5

FTE-4 1089 I

6 SURV-6 1563 7

FTE-6 1609

}

L P-81322 Page 3 December 11, 1931 f

Accordingly, destructive PIs results for FSV fuel will still be available over a wtde range of exposures if destructive PIE of the Segment 2 surveillance element is deleted.

4.

The nondestructive examination of the Segment 2 fuel elements at the site will still be performed with the remaining FY-82 DOE funding.

These examinations will provide information on graphite behavior w'ich cannot be n

obtained by monitoring plant operation in the same manner that information on fuel particle failure is obtained by monitoring circulating activity.

At PSC's request, General Atomic Company (GAC) reviewed this

^

si tuation. The results of their review and recommendations are summarized in the attached GAC letter, Please note that their recommendations support PSC's position on this matter.

l If you have any questions regarding this request, please do not hesitate to contact us.

PSC requests that your decision be provided i

by March 1, 1981 so that appropriate Segment 2 spent fuel shipping arrangements can be made.

Very truly yours,

[k,/)M C. R. Lee, Vice President Electric Production ORL/JCS:pa Attachment S

i l

t l

i --

p_81322 Attachment r

f I

GENERA. ATOtsC COGARANY p O. Box 81000 SAN DIE 30, CAUFOANA 92138 (714) 455 3000 October 9, 1981 GP-1175 Mr. 'd. L. Brey, Manager Nuclear Engineering Division Public Service Cocpany of Colorado 12013 Eas: 46th Avenue, suite 440 Denver, CO 80239 Subje ::

Segment 2 Fuel Surve'llance

Dear Mr. Erey:

As has been discussed in recent telephone conversations a=ong Mike Hol=es, Jack Levin, Don Kcwal, Dave Alberstein, and others, DOE funding allocations for the Fort St. Vrain Fuel Surveillance Progra: have been reduced for FY-82, and a =odification of the progra: is necessary. The staff of the GAC Core Materials Eranch has reviewed the progra: and has recoc= ended that, given current budge ' 4 ' ations, the destructive post-irradiation examination

(?!E) of the Seg=en: 2 surveillance element be deleted fro the progra=.

Non-des:ructive examinatien of precharacterized Segmen: 2 fuel ele =ents at th1 site should be carried out as originally planned.

The reco==endation to delete the Seg=en: 2 destructive PIE is based upon the following considerations:

1.

The results of the destructive FIE of the Segment 1 surveillance ele =en: indicated : hat no coated fuel particle failure occurred during Cycle 1 operation.

Since circulating activity levels during Cycle 2 have been equal to c: less than those during Cycle 1 and have been essentially constant throughou: the cycle, 1: is expec:ed that no in-service failure would be observed in a ?!? of the Seg=en: 2 fuel.

2.

The Seg=en: 2 surveillance ele =ent has received a relatively s=all incre= ental exposure over the Seg-

=ent I surveillance ele =ent.

Additional PIE infor-I

...,c,+,...

-.._y

,__~,..r-,ex,,,,,,._,,r_~m,__,.....,__,w,,,.__.

._,_,.,,e..w.

m

. _,,~_, _

m-,..-.,

e l

l i

=ation at low exposures is not expected to take a j

significant additional contribution to our under-standing of coated fuel particle performance under norual operating conditions.

3.

Fuel Test Ele =ents FTE-2, 4, and 6 each contain 88 FSV reference fuel rods. These test elements are scheduled for destructive PIE under DOE funding for the large RTGR program.

Accordingly, destructive PIE results for FSV fuel will still be available over a wide range of exposures if destructive PIE of the Segment 2 surveillance ele =ent is deleted.

GAC requests that PSC ask NRC for approval to eliminate the destructive PIE of the Segment 2 surveillance element.

If GAC can be of any assist-ance to PSC in this endeavor, please feel free to contact me.

Verv truly yours, O

~

'Jilliam A. Graul, Manager Fort St. Vrain Project

(

)