ML20117H671
| ML20117H671 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 08/23/1996 |
| From: | Hunger G PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20117H673 | List: |
| References | |
| NUDOCS 9609090367 | |
| Download: ML20117H671 (5) | |
Text
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Station Support Department
=525=-
' PECO NUCLEAR nw %< ~v Nuclear Group Headquarters l
A UNtr or PECO ENf#cy 965 Chesterbrook Boukvard I
Wayne, PA 190875691 j
l August 23, 1996 Docket Nos. 50-277 50-278 License Nos. DPR-44 DPR-56 5
U.S. Nuclear Regulatory Commission i
Attn: Document Control Desk Washington, DC 20555 j
Subject:
Peach Bottom Atomic Power Station, Unit 2 Revision to License Change Request No. 96-01 l
Reference:
Letter from G. A. Hunger, Jr. (PECO Energy) to U.
S.
Nuclear Regulatory Commission, dated i
March 25, 1996 j
Dear Sir:
In the above Referenced letter, PECO Energy Company (PECO Energy) submitted, in accordance with 10 CFR 50.90, License Change Request (LCR) No. 96-01 which requested a change to the Peach Bottom Atomic Power Station (PBAPS), Unit
- 2. Facility Operating License.
This proposed change was to revise TS Section 2.0,
" Safety Limits" to incorporate new Safety Limit Minimum Critical Power Ratios (SLMCPRs) due to the use of the GE13 fuel product line.
PECO Energy hereby requests that our referenced submittal be revised such that: 1) the submitted PBAPS, Unit 2 Technical Specifications (TS) page 2.0-1 be deleted and replaced with the Attachment 1 TS page 2.0-1 for PBAPS, Unit 2,
- 2) the letter contained in the original submittal be replaced with the enclosed Attachment 2 letter from R.
M.
Butrovich (GENE) to H. J. Diamond (PECO Energy), " Peach Bottom Unit 2 Cycle 12 Safety Limit MCPR," dated August 8, 1996, and
- 3) the No Significant Hazards Consideration be revised as discussed below.
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August 23, 1996 Paga 2 l
j As discussed in the enclosed Attachment 2 letter, PECO Energy was advised by General Electric Nuclear Energy (GENE) that the methodology used by GENE to calculate the generic SMCPR may not always yield the most conservative result.and that GENE has performed a plant unique evaluation for PBAPS, Unit 2, Cycle 12.
As a result of this plant unique evaluation, the SMCPR for PBAPS, Unit 2,
Cycle 12, is 1.11 (Generic GE13 l
SLMCPR is 1.09). The single loop operation SLMCPR is 1.13 and is determined on a generic approach.
A 0.02 penalty for single loop operation is applied to the cycle-specific SIMCPR value of 1.11.
The 0.02 penalty has been _ confirmed to be conservative based on a plant specific analysis by GENE as documented in GENE's Design Record File.
The calculation of the cycle-specific SLMCPR value for PBAPS, Unit 2, Cycle 12, is based upon USNRC-approved methods
(" General Electric Standard Application for Reactor Fue.1," NEDE-24011-P-A-11, and U.S. Supplement, NEDE-24011-P-A-11-US, November 17, 1995) and interim (reconfirmation) implementing procedures. Revision 11 of the aforementioned document, "GESTAR II", requires that the SIMCPR be reconfirmed each cycle.
This reconfirmation was performed using the interin (reconfirmation) implementing procedures which the USNRC staff discussed with GENE during their meetings on April 17, 1996 and May 6, 1996 through May 10, 1996.
These reconfirmation procedures utilize cycle-specific parameters which include: 1) the actual core loading,
- 2). conservative variations of projected control blade
- patterns, 3) the actual bundle parameters (e.g.,
local peaking), and 4) the full cycle exposure range. Specifically, the implementing procedures involve reconfirmation of the applicability of the generic SIMCPR to PBAPS, Unit 2, Cycle 12.
This reconfirmation was performed by incorporating cycle-specific parameters into the analysis described in Section 1.1.5 of GESTAR II, Revision 11, and indicates that the
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generic SIMCPR will not bound PBAPS, Unit 2,
Cycle 12)
I therefore, the resulting cycle-specific SLMCPR will be applied to PBAPS, Unit 2, Cycle 12.
Instead of using a typical, large, high-power-density plant and bounding equilibrium core, the actual projected PBAPS, Unit 2, Cycle 12 core loading was i
used and the analysis was performed at the maximum licensed thermal power for PBAPS, Unit 2.
Multiple exposure points in the projected Cycle 12 were checked to obtain the limiting case.
The core radial power distribution was manipulated _by adjusting control rods to maximize the number of bundles near thermal limits using only symmetric control rod patterns. The dependency of the local power distributions on specific bundle design characteristics is explicitly addressed by using actual bundle and pin-by-pin R-factors.
The number of rods anticipated to be susceptible to boiling transition is uniquely defined by the core loading and local power distributions and from those_ used in previous. generic analyses.
The SLMCPR is selected such that 99.9% of the rods in the core are expected to avoid boiling transition.
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August 23, 1996 Pago 3 In our review of the discussion contained in the Information Supporting a Finding of No Significant Hazards Consideration contained in the Referenced letter, we have determined that the references to the GENE. analyses have been updated as
(
provided below. However, we have concluded that this revision l
to LCR No. 96-01 for PBAPS, Unit 2 TS still does not involve l
a Significant Hazards Consideration.
Additionally, we have determined that this revision does not alter our evaluation of any of the 10 CFR 50.59 standards, and, therefore, does not i
affect our conclusion that LCR No. 96-01 does not constitute an unreviewed safety question.
We have also concluded that the proposed revision does not affect the Information j
Supporting an Environmental Impact Assessment.
1.
The Dronosed TS chanaes do not involve a sianificant increase in the erobability or consecuences of an accident oreviousiv evaluated.
I The derivation of the cycle-specific SINCPRs for incorporation into the TS, and its use to determine cycle-specific thermal limits, have been performed using USNRC-approved methods as discussed in " General Electric Standard Application for Reactor Fuel," NEDE-24011-P-A-11, and U.S. Supplement, NEDE-24011-P-A-11-US, November 17, 1995 and interin (reconfirmation) implementing procedures.
This change in SIMCPRs cannot increase the probability or severity of an accident.
The basis of the SINCPR calculation is to ensure that greater than 99.9% of all fuel rods in the core avoid boiling transition if the limit is not violated. The new SINCPRs preserve the existing margin to transition boiling and fuel damage in the event of a postulated accident. The fuel licensing acceptance criteria for the SLMCPR calculation apply to PBAPS, Unit 2, Cycle 12 in the same manner as they have applied previously.
The probability of fuel damage is not increased.
Therefore, the proposed TS changes do not involve an increase in the probability or consequences of an accident previously evaluated.
2.
The Dronosed TS chances do not create the nossibility of a new or different kind of accident from any accident j
oraviously evaluated.
j The SINCPR is a TS numerical value, designed to ensure i
that transition boiling does not occur in 99.9% of all fuel rods in the core during the limiting postulated i
accident.
It cannot create the possibility of any new type of accident.
The new SIMCPRs are calculated using USNRC-approved methods
(" General Electric Standard Application for Reactor Fuel," NEDE-24011-P-A-11, and U.S. Supplement, NEDE-24 011-P-A-11-US, November 17, 1995) and interin (reconfirmation) implementing procedures.
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i Auguut 23, 1996 Pnga 4 Therefore, the proposed TS changes do not create the possibility of a new or different kind of accident, from any accident previously evaluated.
3.
The Droposed TS chances do not involve a sianificant reduction in a marain of safety.
The margin of safety as defined in the TS Bases will remain the same.
The new SLMCPRs are calculated using USNRC-approved methods
(" General Electric Standard Application for Reactor Fuel," NEDE-24011-P-A-11, and U.S. Supplement, NEDE-24011-P-A-11-US, November 17, 1995) and interim (reconfirmation) implementing procedures which are in accordance with the current fuel licensing criteria.
The SLMCPRs remain sufficient to ensure that greater than 99.9% of all fuel rods in the core will avoid boiling transition if the limit is not violated, thereby preserving the fuel cladding integrity.
Therefore, the proposed TS changes do not involve a j
reduction in a margin of safety.
If you have any questions, please do not hesitate to contact us.
Very truly yours, I
G. A. Hunge, Jr.,
Director - Licensing
Enclosures:
Affidavit, Attachment 1, Attachment 2 cc:
H. J. Martin, Administrator, Region I, USNRC W. L. Schmidt, USNRC Senior Resident Inspector, PBAPS R. R. Janati, Commonwealth of Pennsylvania 1
MMONWEALTH OF PENNSYLVANIA C
f ss.
COUNTY OF CHESTER D. B.
Fetters, being first duly sworn, deposes and says:
That he is Vice President of PECO Energy Company; the Applicant herein; that he has read the attached revision to License Change Request No.
96-01, for Peach Bottom Facility Operating License DPR-44, and knows the contents thereof; and that the statements and matters set forth therein are true and correct to the best of his knowledge, information and belief.
h_U Vice President Subscribed and sworn to before me this 2 day of 1996.
Alb Nota Public Notarial Seal Mary Lou Skrocki. Notary Public Tredyffnn Twp. Chester County My Commission Expires May 17,1999 i.6.23, Punnsp anc udaion m I.~ ~
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