ML040840483

Amended Information Regarding Radiological Consequences for MOX Fuel Lead Assemblies

ML040840483
Person / Time
Site:	Mcguire, Catawba, McGuire
Issue date:	03/16/2004
From:	Mccollum W Duke Energy Corp
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TAC MB7863, TAC MB7864, TAC MB7865, TAC MB7866
Download: ML040840483 (9)

Text

Duke

• Power.

A Duhr Enrgy Company Duke Power Energy Center PO. Box 1006 Charlotte, NC 28201-1006 March 16,2003 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555-0001

Subject:

Duke Energy Corporation Catawba Nuclear Station Units 1 and 2, Docket Nos. 50-413, 50-414 Amended Information Regarding Radiological Consequences for MOX Fuel Lead Assemblies

References:

1. M. S. Tuckman letter dated February 27, 2003 to U. S. Nuclear Regulatory Commission (NRC), Catawba Nuclear Station Units 1 & 2, Docket Nos. 50-413, 50-414, McGuire Nuclear Station Units 1 & 2, Docket Nos. 50-369, 50-370, Proposed Amendments to the Facility Operating License and Technical Specifications to Allow Insertion of Mixed Oxide (MOX) Fuel Lead Assemblies and Request for Exemption from Certain Regulations in 10 CFR Part 50

2. NRC Letter dated July 25, 2003 to M. S. Tuckman, Request for Additional Information Re: Mixed Oxide Lead Fuel Assemblies (TAC Nos. MB7863, 7864, 7865, 7866)

3. M. S. Tuckman Letter dated November 3, 2003 to the NRC, MOX Fuel Lead Assembly License Amendment Request

4. NRC Letter dated February 4, 2004 to H. B. Barron, Request for Additional Information Re: Mixed Oxide Lead Fuel Assemblies (TAC Nos. MB7863 and MB77864)

5. H. B. Barron Letter dated March 1, 2004 to the NRC, MOX Fuel Lead Assembly License Amendment Request In Reference 1 Duke Energy submitted an application to amend the operating licenses of McGuire and Catawba to allow the use of four MOX fuel lead assemblies. The application was subsequently amended to apply to Catawba only.

In Reference 2 the NRC staff transmitted a Request for Additional Information (RAI) related to the Reference 1 license amendment request. Duke responded to questions related to radiological assessments in Reference 3. In the Reference 3 Response to Question 3b, Duke evaluated the

--DC)

U. S. Nuclear Regulatory Commission March 16,2004 Page 2 bounding impact of four MOX fuel lead assemblies on doses by adjusting dose results based on relative releases of 1-131. The adjustment was incorrectly applied. Attachment I to this letter provides a correction to the Response to Question 3b as contained in Reference 3.

In Reference 4 the NRC staff transmitted another RAI related to the radiological consequences of using four MOX fuel lead assemblies. Duke responded to that RAI in Reference 5. As was the case in Reference 3, the adjustment to the dose results was incorrectly applied in the Response to Question 1. Attachment 2 to this letter provides a correction to the Response to Question 1 as contained in Reference 5.

The corrections provided herein have no significant impact on the conclusions in the submittals.

This statement applies both to Reference 2 and Reference 4. Inquiries on this matter should be directed to Michael T. Cash at (704) 382-5826.

W.R. Mc Collum Senior Vice President Nuclear Generation Duke Energy Corporation Attachments

U. S. Nuclear Regulatory Commission March 16, 2004 Page 3 Oath and Affirmation W.R. Mc Collum affirms that he is the person who subscribed his name to the foregoing statement, and that all the matters and facts set forth herein are true and correct to the best of his knowledge.

W.R.

Collur Subscribed and sworn to before me on this 16 alp day of A

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@°[

Notary lic MICHAEL T. CASH My Commission expires:

Notary Public My Cmmisionexpies:Lincoln County, North Carolina Commission Expires January 22, 2008 Jmnavi 2-Z 1 2ot Date Seal

U. S. Nuclear Regulatory Commission March 16,2004 Page 4 cc: with attachment L. A. Reyes U. S. Nuclear Regulatory Commission Regional Administrator, Region II Atlanta Federal Center 61 Forsyth St., SW, Suite 23T85 Atlanta, GA 30303 R. E. Martin (addressee only)

NRC Project Manager U. S. Nuclear Regulatory Commission Mail Stop 0-8G9 Washington, DC 20555-0001 E. F. Guthrie Senior Resident Inspector U. S. Nuclear Regulatory Commission Catawba Nuclear Station J. B. Brady Senior Resident Inspector U. S. Nuclear Regulatory Commission McGuire Nuclear Station Diane Curran Harmon, Curran, Spielberg & Eisenberg, LLP 1726 M Street, N.W.

Suite 600 Washington, DC 20036 Mary Olson Director, Southeast Office Nuclear Information and Resource Service P.O. Box 7586 Asheville, NC 28802 H. J. Porter, Director Division of Radioactive Waste Management Bureau of Land and Waste Management

U. S. Nuclear Regulatory Commission March 16,2004 Page 5 Department of Health and Environmental Control Columbia, SC 29201

U. S. Nuclear Regulatory Commission March 16,2004 Page 6 bcc: attachment Richard Clark-DCS Patrick Rhoads-DOE David Alberstein-DOE Don Spellman-ORNL NCMPA-1 NCEMC PMPA SRE bcc: wlattachment (via email)

S. P. Nesbit M. T. Cash F. J. Verbos J. L. Eller S. P. Schultz L. F Vaughn M. W. Scott L. J. Rudy J. Hoerner - Framatome ANP G. A. Meyer - Framatome ANP bcc: w/attachments (paper copy)

NRIA File/ELL - ECO50 MOX File 1607.2304 Catawba Document Control File 801.01-CN04DM Catawba RGC Date File (J. M. Ferguson - CNOlSA)

ATTACHMENT 1 Corrections to November 3, 2003 Submittal Response to RADIOLOGICAL CONSEQUENCES Question 3b, beginning on p. 93 Note: Numerical values with changes from previously reported values are enclosed in brackets []

The fourth paragraph in "Evaluations" (i.e., the paragraph beginning "The LOCA evaluation..."

plus the bulleted list) should read:

The LOCA evaluation is illustrated as follows:

• The number of MOX fuel lead assemblies assumed to be failed (4) is multiplied by the increase in I-131 inventory in MOX relative to LEU (1.09) and a factor to account for the increase in the release fraction being assumed for I-131 for MOX (1.5) to give 6.54. This value represents the equivalent number of LEU assemblies that correspond to 4 MOX assemblies. Note: the increase in 1-131 release fraction is per the response to Radiological Consequences Question 3(g).

• The 6.54 value is added to the number of LEU assemblies assumed to be failed (193

- 4 = 189) to give 195.54.

• The 195.54 sum is divided by the total number of failed assemblies (193) to give 1.0132, the dose multiplier for a LOCA with four MOX fuel lead assemblies.

• Subtracting one from the dose multiplier gives 0.0132 or [1.32%], the fractional or percentage increase in dose due to four MOX fuel lead assemblies.

• The existing dose results are multiplied by the dose multiplier of 1.0132 to calculate the projected thyroid dose with four MOX fuel lead assemblies. For the EAB thyroid dose for the TB) LOCA scenario, the current dose is 89 Rem. Multiplied by 1.0132, this gives a total projected thyroid dose of [90.171 Rem with four MOX fuel lead assemblies.

The last paragraph in "Evaluations" should read:

The same calculational process yields an increase in the locked rotor thyroid dose of

[11.96%] and the rod ejection thyroid dose of [2.63%]. The respective total projected exclusion (EAB) thyroid doses are [4.14] Rem and [1.03] Rem. All of these increases are very small. These results are summarized in Table Q3(b)-2. The results do not remove an appreciable amount of margin.

In addition the following should be considered when reading the "Evaluations" section following the above paragraph:

It should be noted that this methodology provides a conservatively high estimation of the dose impact of using MOX fuel. For the locked rotor and rod ejection accidents that involve less than 100% fuel failure, the methodology assumes that all of the MOX fuel rods fail 1

while only some of the LEU fuel rods fail, thereby magnifying the relative impact of MOX fuel. As shown in Tables Q3(b)-1 and Q3(b)-2, the absolute impact on dose is still small.

Modify Tables Q3(b)-1 and Q3(b)-2 to read as follows.

Table Q3(b)-1 Offsite and Control Room Doses with LEU Cores and Projected Doses with MOX Lead Assembly Cores for LOCAs with TID and AST Releases MOX Lead All LEU MOX Lead TID Dose LmIt All LEU Core &

Assemblies &

TEDE Dose Core & AST Assemblies &

Receptor (Rem Thyroid)

TID Releases

' Increased TID Umit Releases 2 Increased (Rem Thyroid)

Releases (Rem TEDE)

Re TEDEs AST Releases (Rem Thyroid)

(em

)

(Rem TEDE)

EAB 300 89

[90.2]

25 7.2

[7.29]

LPZ 300 25 125.3]

25 4.0

[4.05]

Control 30 5.3

[5.37]

5 2.7

[2.74]

R o o m_

1 Catawba UFSAR 2 Reference 03(b)-3 Table Q3(b)-2 Offsite Thyroid Doses with Full LEU Cores and Projected Thyroid Doses with MOX Lead Assemblies for Locked Rotor and Rod Ejection Accidents 1 Standard TID releases.

2 Increased TID releases.

3 Note that for those accidents where there are multiple applicable cases (such as for concurrent and pre-exiting spiking), the result of the case with the highest dose is shown.

2

ATrACHMENT 2 Correction to the March 1, 2004 Submittal Responses to Radiological Question 1, p. S Note: Numerical values with changes from previously reported values are bracketed [ ]

Under "Response Conclusion," the last sentence should read as follows:

Examining up to a 23% increase in I-131 activity due to MOX as suggested in the question would increase the calculated final dose results by at most [OA] Rem from those reported in Reference Q1-2.