ML082040579

Additional Information for the Long-Term Carborundum Coupon Surveillance Program

ML082040579
Person / Time
Site:	Calvert Cliffs
Issue date:	07/18/2008
From:	Spina J Constellation Energy Group
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML082040579 (5)

Text

James A. Spina Vice President 0

Constellation Energy-Nuclear Generation Group Calvert Cliffs Nuclear Power Plant, Inc.

1650 Calvert Cliffs Parkway Lusby, Maryland 20657 410.495.5200 410.495-3500 Fax July 18, 2008 U. S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION:

SUBJECT:

Document Control Desk Calvert Cliffs Nuclear Power Plant Unit No. 1; Docket No. 50-317 Additional Information for the Long-Term Carborundum Coupon Surveillance Program

REFERENCES:

(a)

Letter from Mr. J. A. Spina (CCNPP) to Document Control Desk (NRC),

dated May 10, 2007, Long-Term Coupon Surveillance Program for the Unit 1 Spent Fuel Pool (b)

Letter from Mr. J. A. Spina (CCNPP) to Document Control Desk (NRC),

dated January 10, 2008, Request for Additional Information re: Long-Term Carborundum Coupon Surveillance Program Calvert Cliffs Nuclear Power Plant, Inc. submitted a request to implement a long-term carborundum coupon surveillance program at Calvert Cliffs Unit 1 (Reference a) and responded to the Nuclear Regulatory Commission staff's questions (Reference b). The Nuclear Regulatory Commission staff has determined that additional information is required to complete their review of the coupon surveillance program. The requested additional information is attached.

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Document Control Desk July 18, 2008 Page 2 Should you have questions regarding this matter, please contact Mr. Jay S. Gaines at (410) 495-5219.

Ve yoZ STATE OF MARYLAND COUNTY OF CALVERT

TO WIT:

I, James A. Spina, being duly sworn, state that I am Vice President - Calvert Cliffs Nuclear Power Plant, Inc. (CCNPP), and that I am duly authorized to execute and file this License Amendment Request on behalf of CCNPP. To the best of my knowledge and belief, the statements contained in this document are true.and correct. To the extent that these statements are not based on my personal knowledge, they are based upon information provided by other CCNPP employees and/or consultants. Such information has been reviewed in accordance with company practice and I believe it to be reliable.

Subscribed and sworn before me a Notary Public in and for the State of Maryland and County of this day of

,2008.

/1

,,,/

WITNESS my Hand and Notarial Seal:

My Commission Expires:

6 4/J* /

Notary Public

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r2 Da t'e 0/

JAS/PSF/bjd

Attachment:

(1)

Additional Information Concerning the Carborundum Coupon Surveillance Program cc:

D. V. Pickett, NRC S. J. Collins, NRC Resident Inspector, NRC S. Gray, DNR

ATTACHMENT (1)

ADDITIONAL INFORMATION CONCERNING THE CARBORUNDUM COUPON SURVEILLANCE PROGRAM Calvert Cliffs Nuclear Power Plant, Inc.

July 18,2008

I ATTACHMENT (1)

ADDITIONAL INFORMATION CONCERNING THE CARBORUNDUM COUPON SURVEILLANCE PROGRAM Request The licensee's current surveillance program includes:

Surveillance every four years: 2009, 2013, 2017, 2021, 2025, 2029, 2033, 2037, 2041, 2045, 2049, and 2053 One coupon extracted from the spent fuel pool each surveillance Inspections performed during each surveillance:

o Visual o

Weight o

Dimensional: Length and Width Based on prior staff approvals of neutron absorption material surveillance programs, the following information should be included and discussed in the 'surveillance program. Examples of prior approvals include: Clinton (ML052930404) and ANO-2 (ML072620412).

Given that areal density measurements should be performed to verify the results of the visual, weight, and dimensional inspections and to -ensure the performance of the carborundum, the staff requests the following schedule for areal density measurements (based on prior staff approvals).

a) 2009, 2017, 2025, 2037 and 2053

Response

Calvert Cliffs agrees to perform areal density measurements on the coupons removed in 2009, 2017, 2025, 2037, and 2053.

Request The acceptance criteria for each inspection should be provided as part of the surveillance program. Based on prior staff approvals for use of neutron absorbtion materials, the staff suggests the following:

a.

Visual: no gross changes or deterioration

b.

Weight: +/- X percent and compared to the baseline

c.

Length and Width: +/- X inches or +/- X percent and compared to the baseline

d.

Areal: > X percent decrease in B-10 and compared to the baseline

Response

The acceptance criteria for the surveillance program will be as follows:

a.

Visual: No gross changes or deterioration

b.

Weight: > +/- 26% compared to baseline

c.

Length and Width: +/- 0.5 inches compared to baseline

d.

Areal: > 0.0 177 g/cm2 Request Corrective actions for each inspection should be provided as part of the surveillance program. Based on prior staff approvals for use of neutron absorbing materials, the staff suggests the following:

a.

If visual, weight, or dimensional acceptance criteria are not met, then perform areal density, regardless if it was scheduled or not.

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ATTACHMENT (1)

ADDITIONAL INFORMATION CONCERNING THE CARBORUNDUM COUPON SURVEILLANCE PROGRAM

b.

If visual, weight, dimensional, or areal density acceptance criteria are not met, then expand the scope of the surveillance to include additional coupons. Expanded inspections should include visual, weight, dimensional, and areal density.

Response

Calvert Cliffs concurs with performing an areal density measurement on a coupon that does not meet visual, weight, or dimensional acceptance criteria. If the areal density measurement meets the acceptance criteria, then expansion of the surveillance program will be determined by evaluations done as part of the corrective action program. If the areal density measurement does not meet the acceptance criteria, then additional coupons will be removed for visual, weight, and dimensional inspections.

Regunest A discussion of the corrective actions that will be taken if acceptance criteria are not met for the expanded inspections should also be included in the surveillance program.

Response

If the acceptance criteria are not met for an expanded inspection we will perform an investigation (including using any areal density measurement taken) evaluating the neutron absorbing capabilities. If the areal density testing reveals degradation, the impact on k~ff would be evaluated. The intent of the evaluation would be to confirm that the value of kef for spent fuel storage in the spent fuel pool remains less than 0.95. After testing, coupons will be returned to the coupon tree, if possible, to support long-term testing.

Reuiuest Please discuss your statement "The objection to performing areal density measurements on withdrawn coupons was that coupons subjected to such measurements would be unavailable for reinsertion."

Response

Areal density testing cannot be performed on site and the coupon must be shipped to an appropriately equipped laboratory. The coupons are very brittle and any handling beyond the minimum necessary to take on-site measurements and weight cause the coupon to abrade and flake. These abrasions and flaking change the surface of the coupon, as well as the dimension and weight, thus making the coupon unsuitable for reinsertion.

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