ML062630071
| ML062630071 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 09/19/2006 |
| From: | Harden P Nuclear Management Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML062630071 (3) | |
Text
N Palisades Nuclear Plant Committed to Nuclear ExceNenc Operated by Nuclear Management Company, LLC September 19,2006 10 CFR 50, Appendix H U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Palisades Nuclear Power Plant Docket 50-255 License No. DPR-20 Revision to Reactor Vessel Surveillance Coupon Removal Schedule Pursuant to 10 CFR 50, Appendix H, lll.C.3, Nuclear Management Company, LLC (NMC) is requesting Nuclear Regulatory Commission (NRC) review and approval of the enclosed revision to the surveillance capsule removal schedule for the Palisades Nuclear Plant. The reactor vessel surveillance capsule removal schedule presently includes removal of surveillance capsule W-280, during the 1 gth refueling outage, W-260 during the 26" refueling outage, and W-80 during the 2gth refueling outage.
NMC is requesting to defer removal of W-280 and W-260 until a more significant level of fluence has accumulated. In addition, NMC is requesting to revise the withdrawal schedule for W-80, as described in Enclosure 1.
Approval of this proposed change is requested no later than September 1, 2007.
Summary of Commitments This letter contains no new commitments and no revisions to existing commitments.
Site Vice President, Palisades Nuclear Plant Nuclear Management Company, LLC Enclosures (1 )
CC Administrator, Region Ill, USNRC Project Manager, Palisades, USNRC Resident Inspector, Palisades, USNRC 27780 Blue Star Memorial Highway Covert, Michigan 49043-9530 Telephone: 269.764.2000
ENCLOSURE 1 REVISION TO REACTOR VESSEL SURVEILLANCE PROGRAM PALISADES NUCLEAR PLANT The Palisades Nuclear Plant (PNP) reactor vessel surveillance capsule removal schedule presently includes removal of surveillance capsule W-280, during the 1 gth refueling outage, W-260 during the 26th refueling outage, and W-80 during the 2gth refueling outage. NMC is requesting to defer removal of W-280 and W-260 until a more significant level of fluence has accumulated. In addition, NMC is requesting to revise the withdrawal schedule for W-80. Surveillance capsule W-100 was recently removed at a fluence of 2.1 0 x 1 ~'~n/cm*.
The incremental effect of neutron fluence on material properties become less significant as fluence accumulates. It is considered prudent to defer removal of W-280 and W-260 until a more significant level of fluence has accumulated.
The currently approved reactor vessel surveillance capsule removal schedule follows:
Approved Surveillance Capsule Withdrawal Schedule The PNP reactor vessel surveillance program is designed to comply with the requirements of ASTM E 185-66. ASTM E 185-66 recommends 3 or more surveillance capsules, one of which corresponds to end of life. 10 CFR 50 Appendix H requires that capsules be tested, to the extent practicable, to the requirements of ASTM E 185-82.
ASTM E 185-82 Table 1 recommends, for a minimum surveillance program, that capsules be withdrawn when capsule neutron fluence is equivalent to end of life neutron fluence at the reactor vessel %T location (First), end of life neutron fluence at the reactor vessel inner wall location (Second), and at a neutron fluence level between end of life neutron fluence and twice end of life neutron fluence (Third). The surveillance capsules should be removed at the following neutron fluence levels.
ASTM E 185 Preferred Neutron Fluence x 10 (n/cm2) for Capsule Withdrawal The surveillance capsules removed to date demonstrate that the surveillance program meets the minimum requirements.
Page 1 of 2 Circumferential Weld, Base Metal 1.238 2.061 2.061 < f < 4.122 Capsule First Second Third Axial Welds 0.896 1.492 1.492 < f < 2.984
Withdrawn Capsules (and Fluence) That Meet the Intent of ASTM E 185 Assuming the operating license is renewed, the surveillance capsule withdrawal scheduled should be revised to remove the capsules at the following neutron fluence levels.
Capsule First Second Third ASTM E 185 Preferred Neutron Fluence x 10" (n/cm2) for Capsule Withdrawal for License Renewal Axial Welds W-290 (0.926)
W-110 (1.66)
W-100 (2.1 0)
The following surveillance capsules best meet the intent of ASTM E 185-66 and E 185-82 for the license renewal period.
Circumferential Weld, Base Metal W-1 1 0 (1.66)
W-100 (2.1 0)
A-240 (4.01)
Capsule First Second Third Capsules (and Fluence) That Meet the Intent of ASTM E 185 for License Renewal Axial Welds 1.251 2.084 2.084 c f c 4.168 Removing surveillance capsule W-80, as scheduled, supports the minimum requirements for the surveillance program for the license renewal period. It is recommended the surveillance program be revised to hold the remaining untested surveillance capsules in reserve to meet future needs. The PNP reactor vessel surveillance capsule removal schedule should be revised as follows:
Circumferential Weld, Base Metal 1.800 2.998 2.998 < f c 5.996 Capsule First Second Third Proposed Surveillance Capsule Withdrawal Schedule 1 "NMC Response to NRC Requests for Additional Information Dated November 30, 2005 Relating to License Renewal for the Palisades Nuclear Plant," January 13, 2006 (RAI B2.1.16-2)
Axial Welds W-110 (1.66)
W-100 (2.1 0)
W-80 (3.06)
Page 2 of 2 Circumferential Weld, Base Metal W-I00 (2.1 0)
W-80 (3.06)
A-240 (4.01)