ML20212K936
| ML20212K936 | |
| Person / Time | |
|---|---|
| Site: | Maine Yankee |
| Issue date: | 01/21/1987 |
| From: | Whittier G Maine Yankee |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| GDW-87-17, MN-87-11, NUDOCS 8701290242 | |
| Download: ML20212K936 (3) | |
Text
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MAIRE HARHEE ATOMIOPOWER00MPARUe
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(207) 623-3521 e
January 21, 1987 MN-87-11 GDH-87-17 United States Nuclear Regulatory Commission Attention: Document Control Desk Hashington, D. C.
20555 Reference (a)
License No. DPR-36 (Docket No. 50-309)
(b) MYAPCo. Letter to USNRC dated January 12, 1987 (MN-87-04)
Proposed Change 128 - Cycle 10 Technical Specifications
Subject:
Proposed Change No.128 - No Significant Hazards Consideration Gentlemen:
Enclosed is a revised no significant hazards consideration for the proposed Maine Yankee Cycle 10 Technical Specifications, Reference (b).
Please replace Attachment A of Reference (b) with the enclosed pages.
Very truly yours, HAINE YANKEE ATOMIC POWER COMPANY
}W
. D. Whittier, Manager Nuclear Engineering and Licensing GDH/hbg Enclosure cc: Mr. Ashok C. Thadani Mr. Richard H. Vollmer Mr. Pat Sears Mr. Cornelius F. Holden
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.n MAINE YANKEE ATOMIC POWER COMPANY ATTACHMENT A PROPOSED CHANGE 128 REV. 1 (MN-87-04) l Descrintion'of Pronosed Chance The proposed changes provided in Attachment C would modify the Technical Specifications to reflect the operating limits for the Cycle 10 reload core.
Sionificant Hazards Evaluation
.The proposed changes to the Technical Specifications for the Cycle 10 operation of the Maine Yankee plant have been evaluated against the standards of 10 CFR 50.92 and have been determined to not involve a significant hazards consideration.
These proposed changes do not:
1.
Involve a significant increase in the probability or consequence of an accident previously evaluated.
The Cycle 10 refueling will involve the discharge of 73 fuel assemblies and insertion of 72 new assemblies and one previously irradiated assembly. The new fuel assemblies are fabricated by Combustion Engineering and are not significantly different from those previously used at Maine Yankee.
In previous reload cores at Maine Yankee and other facilities, the NRC has found the fuel design to be acceptable. The Control Element Assembly (CEA) pattern for Cycle 10 is identical to that_used in Cycle 9.
Also, the thermal, thermal-hydraulic, and physics characteristics for Cycle 10 are not significantly different from those of Cycle 9.
These changes are described in detail in Attachment D.
Therefore, these proposed changes which support the operation of Maine Yankee for Cycle 10 do not increase the probability of an accident previously evaluated.
The Cycle 10 design has been evaluated to demonstrate the acceptability of events previously evaluated in the Maine Yankee Final Safety Analysis Report (FSAR). The acceptance criteria ~for the evaluation are identical to those which were employed for Cycle 9.
Furthermore, the analytical methods used to demonstrate conformance of the Cycle 10 design are identical to those used in Cycle 9 except for the removal of the flux augmentation factor. The removal of the flux augmentation factor was proposed in Reference (c) and approved by the NRC in Reference (d).
Section 5 of the analysis in Attachment D summarizes the effects of Cycle 10 operation on the consequence of accidents previously -
evaluated in the Maine Yankee FSAR.
For these transients where the parameters for Cycle 10 are not bounded by previous safety analyses, a new or revised analysis was performed. They are:
1)
Boron Dilution 2)
CEA Ejection 3)
CEA Mithdrawal 4)
CEA Drop 5)
Loss of Load
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MAINE YANKEE ATOMIC POWER COMPANY
, Other transients that required a partial reanalysis or review included:
1)
Seized RCP Rotor 2)
Excess Load 3)
Loss of Feedwater 4)
Loss of Coolant Flow 5)
Steam Line Rupture 6)
Steam Generator Tube Rupture In each case the reanalysis demonstrated that the applicable acceptance criteria for the accident or transient continue to be met, (see Table 5.3 of Attachment D).
For the remaining transients, the parameters were bounded by previous safety analyses and therefore are not adversely affected by the reload.
Additional information regarding the effect of the proposed Technical Specification changes is found in Section 5 of the Cycle 10 CPAR (Attachment D).
In summary, our evaluation of accidents previously analyzed in the FSAR has demonstrated that all applicable acceptance criteria continue to be met.
Therefore, the proposed Technical Specification changes for Cycle 10 operation do not significantly increase the consequences of an accident previously evaluated.
2.
Create the possibility of a new or different kind of accident from any previously evaluated.
As indicated in Item 1 above and the Cycle 10 CPAR, the reload core for Cycle 10 operation is similar in fuel design, CEA placement, and thermal, thermal-hydraulic, and physics characteristics to that of Cycle 9.
He have concluded that Cycle 10 does not create the possibility of a new or different kind of accident from any previously evaluated.
3.
Involve a significant reduction in a margin of safety.
As indicated in Item 1 above, and the Cycle 10 CPAR, the design of Cycle 10 is similar to Cycle 9.
The methods used to analyze Cycle 10 are the same as were used for Cycle 9 or they have been previously approved by the NRC staff. Additionally, the acceptance criteria for Cycle 10 are the same as Cycle 9.
He have demonstrated that these acceptance criteria continue to be met. He have therefore concluded that Cycle 10 operation does not involve any reduction in a margin of safety.
Maine Yankee has concluded that the proposed changes to Technical Specifications do not involve a significant hazards consideration as defined by 10 CFR 50.92.
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