ML113180238

Response to Request for Additional Information Concerning the License, Amendment Request Associated with the Reactivity Anomalies Surveillance

ML113180238
Person / Time
Site:	Limerick
Issue date:	11/10/2011
From:	Jesse M Exelon Generation Co, Exelon Nuclear
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TAC ME6348, TAC ME6349
Download: ML113180238 (7)

Text

10 CFR 50.90 November 10, 2011 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001 Limerick Generating Station, Units 1 and 2 Facility Operating License Nos. NPF-39 and NPF-85 NRC Docket Nos. 50-352 and 50-353

Subject:

Response to Request for Additional Information Concerning the License Amendment Request Associated with the Reactivity Anomalies Surveillance

References:

1) Letter from M. D. Jesse (Exelon Generation Company, LLC) to U.S.

Nuclear Regulatory Commission, "License Amendment Request -

Reactivity Anomalies Surveillance," dated June 2,2011

2) Letter from J. D. Hughey (U.S. Nuclear Regulatory Commission) to M. J.

Pacilio (Exelon Generation Company, LLC), "Limerick Generating Station, Units 1 and 2 - Request for Additional Information Regarding License Amendment Request for Reactivity Anomalies Surveillance Requirement (TAC NOS. ME6348 and ME6349)," dated November 9, 2011 In the Reference 1 letter, Exelon Generation Company, LLC (Exelon) requested a proposed change to modify the Technical Specifications (TSs) concerning a change to the method of calculating core reactivity for the purpose of performing the reactivity anomaly surveillance at Limerick Generating Station, Units 1 and 2.

In the Reference 2 letter, the U.S. Nuclear Regulatory Commission requested additional information. Attached is our response to this request.

u.s. Nuclear Regulatory Commission License Amendment Request Reactivity Anomalies Surveillance November 10, 2011 Page 2 Exelon has reviewed the information supporting a finding of no significant hazards consideration and the environmental consideration provided to the U.S. Nuclear Regulatory Commission in Reference 1. The additional information provided in this submittal does not affect the bases for concluding that the proposed license amendment does not involve a significant hazards consideration. In addition, the additional information provided in this submittal does not affect the bases for concluding that neither an environmental impact statement nor an environmental assessment needs to be prepared in connection with the proposed amendment.

Should you have any questions concerning this letter, please contact Tom Loomis at (610) 765-5510.

th I declare under penalty of perjury that the foregoing is true and correct. Executed on the 10 day of November 2011.

Respectfully, Michael D. Jesse Director, Licensing & egu ory Affairs Exelon Generation Com ny, LLC : Response to Request for Additional Information : Revised Markup of Technical Specifications Pages cc: USNRC Region I, Regional Administrator USNRC Senior Resident Inspector, LGS USNRC Project Manager, LGS R. R. Janati, Commonwealth of Pennsylvania

AlTACHMENT 1 Response to Request for Additional Information

Response to Request for Additional Information License Amendment Request Associated Attachment 1 with the Reactivity Anomalies Surveillance Page 1 of 1 Question:

RAI-01: It is implied (but not directly stated) in the licensee's amendment request that PANAC11 is the 3D core simulator code currently used in determination of the predicted core k-effective value. The k-effective value is used to generate the predicted reactivity anomaly curves. Please confirm that PANAC11 is the 3D core simulator code currently used to perform this calculation.

Response

PANAC11 calculates the core keffective (k eff) value. The k eff value is used to generate the predicted reactivity anomaly curves.

Question:

RAI-02: In Attachment 2, "Markup of Technical Specifications and Bases Pages," of the licensee's amendment request, the suggested change to Surveillance Requirement (SR) 4.1.2 does not retain the 1% delta-k/k comparison criterion that is present in the original version of the SR. Comparison criterion is important in determining whether or not the SR is met. Please explain why the 1% delta-k/k comparison criterion was omitted from the SR markup.

Response

Revised Technical Specification pages 3/4 1-2 for Limerick Generating Station, Units 1 and 2 are attached. These pages have been revised to include the 1% delta-k/k comparison criterion.

ATTACHMENT 2 Revised Markup of Technical Specifications Pages Revised Pages (Units 1 and 2) 3/4 1-2

BfACTIVITY CONTROL SYSTEMS 3/4.1.2 REACTI~lIY__AtlQMALlLS lj..t:1ITINU,~lN[llIlQN FOR OPERAllO..]!.l-. = _

~u_'" =me

~~

between the actudl~

~

The reactivity ~e~u.:",l~~~..._~

DE . d n d the predicted' ~_.......~..:l% 6k/k .

heJ.f-APPlICABILITY: .r-_~

ACTION:

With the

d. Within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> perform an analysis to determine and explain the cause of the reactivity difference; operation may continue if the difference is explained and corrected.

b. Otherwise, be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

SURyEILLANCE REOlJIREMElli 4.1.2 The reactivity : -* . . .JI-o- . . .,.-.~.f2~-tO:-h~

~J!])and the predic~t~e~~~~~Y~s~hall be verified to difference between the a~

be less than or equa 1 to 1% i\.k/k: ~r~

d. Ouri ng the fi rst startup following CORE ALTERATIONS, and

b. At least once per 31 effective full power days during POWER OPERATION.

c. The provisions of Specification 4.0.4 are not applicable.

LIMERICK - UNIT 1 3/4 1-2 Amendment No. 29

REACTIVITY CONTROL SYSTEMS 3/4.1.2 REACTIVITY ANOMALIES APPLICABILITY; ACTION:

With the react; vity &iJ?'! e~ference exceedi ng 1% 6k/k:

a. Within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> perform an analysis to determine and explain the cause of the reactivity difference; operation may continue if the difference is explained and corrected.

b. Otherwise, be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

4.1.2 The reactivity u the ifference between the actua oWQ1iJand the predi c~t..:;J,.ed~~,.;:p~~-=-s~h;;""a11 be veri fi ed to be 1 ess than or equal to 1% 6k/k: ~

a. During the first startup following CORE ALTERATIONS, and

b. At least once per 31 effective full power days during POWER OPERATION.

c. The provisions of Specification 4.0.4 are not applicable.

LIMERICK UNIT 2 3/4 1-2