ML17355A187

Removal of the Limerick Generating Station, Unit 2, Reactor Vessel Surveillance Specimen Holder and Capsules at 120-Degree Azimuth

ML17355A187
Person / Time
Site:	Limerick
Issue date:	12/21/2017
From:	Libra R Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
BWRVIP-135, LG-17-172
Download: ML17355A187 (2)

Text

Exelon Generation ~

BWRVIP-135 LG-17-172 December 21, 2017 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

Subject:

Removal of the Limerick Generating Station, Unit 2, Reactor Vessel Surveillance Specimen Holder and Capsules At 120-Degree Azimuth The purpose of this letter is to provide the Nuclear Regulatory Commission (NRC) formal notification that the Limerick Generating Station, Unit 2, reactor vessel surveillance specimen holder and capsules at the 120-degree azimuth location were removed from the reactor during a maintenance outage in October 2017 and will not be re-installed.

During Limerick Generating Station's (LGS) Maintenance Outage (2M54} in October 2017, the reactor vessel surveillance specimen holder located at the 120-degree azimuth was found broken at the specimen rod to basket interface. The specimen basket was found on the reactor pressure vessel (RPV) shroud support plate and the specimen rod remained hanging from the RPV wall. The specimen capsules themselves remained in the basket and intact. The remaining two specimen holders, located at 30-degree and 300-degree azimuths, were examined and showed no signs of wear, degradation or movement. The 30-degree and 300-degree surveillance specimen holders and capsules remain installed in the LGS Unit 2 reactor vessel.

The LGS Reactor Vessel Surveillance program is part of the Boiling Water Reactor Vessel and Internals Project (BWRVIP) Integrated Surveillance Program (ISP) described in BWRVIP-86, Rev. 1-A, and approved by the NRC staff. The schedule for removing surveillance capsules is in accordance the timetable specified in BWRVIP-86, Rev. 1-A for the current license term and for the period of extended operation.

The 120-degree holder is identified in the LGS Updated Final Safety Analysis Report (UFSAR) as Capsule No. 2 and was one of three reactor vessel surveillance specimen holders in the reactor vessel. All three LGS Unit 2 capsules are not identified as ISP test capsules and are defined as "deferred" in the BWRVIP-86, Rev. 1-A, Table 4-8, ISP Test Matrix Results. The ISP intention is that plants leave the capsules defined as "deferred" in the reactor design locations such that they continue to receive exposure to preserve ISP contingency planning.

LGS has consulted with the Electric Power Research Institute (EPRI) BWRVIP ISP program manager, and they concur that reinstallation of the LGS Unit 2 Capsule No. 2 at 120-degree azimuth is not required to support the ISP in either the initial 40-year term or in the ISP 60-year license renewal term.

There are no regulatory commitments contained in this letter.

If there are any questions or if additional information is needed, please contact Ted Ryan at 610-718-3530 Respectfully, Richard W. Libra Vice President - Limerick Generating Station Exelon Generation Co. LLC cc: D. Dorman, Regional Administrator Region I S. Rutenkroger, USNRC Senior Resident Inspector V. Sreenivas, Project Manager