L-15-192, Supplemental Information for the Review of the License Renewal Application (TAC No. ME4640) and License Renewal Application Amendment No. 58

Supplemental Information for the Review of the License Renewal Application (TAC No. ME4640) and License Renewal Application Amendment No. 58

ML15163A195
Person / Time
Site:	Davis Besse
Issue date:	06/12/2015
From:	Lieb R FirstEnergy Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
L-15-192, TAC ME4640
Download: ML15163A195 (10)

Text

FENOC' 5501 North State Route 2 Oak Harbor, Ohio 43449 FirstEnergy Nuclear Operating Company Raymond A Lieb 419-321-7676 Vice President, Nuclear Fax: 419-321-7582 June 12, 2015 L-15-192 10 CFR 54 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

SUBJECT:

Davis-Besse Nuclear Power Station, Unit No. 1 Docket No. 50-346, License Number NPF-3 Supplemental Information for the Review of the Davis-Besse Nuclear Power Station, Unit No. 1, License Renewal Application (TAC No. ME4640) and License Renewal Application Amendment No. 58 By letter dated August 27, 2010 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML102450565), FirstEnergy Nuclear Operating Company (FENOC) submitted an application pursuant to Title 10 of the Code of Federal Regulations, Part 54 for renewal of Operating License NPF-3 for the Davis-Besse Nuclear Power Station, Unit No. 1 (Davis-Besse). Based on a recent plant event, FENOC is providing supplemental operating experience information to support the completion of the Nuclear Regulatory Commission (NRC) review of the License Renewal Application (LRA).

The Attachment provides the supplemental operating experience information for the LRA. The Enclosure provides Amendment No. 58 to the Davis-Besse LRA.

There are no regulatory commitments contained in this letter. If there are any questions or if additional information is required, please contact Mr. Clifford I. Custer, Fleet License Renewal Project Manager, at 724-682-7139.

I declare under penalty of perjury that the foregoing is true and correct. Executed on June 1ztlt, 2015.

sz*ncerly, "'

~tl<vttt#/

- J I l

Raymond A. Lieb

Davis-Besse Nuclear Power Station, Unit No. 1 L-15-192 Page 2

Attachment:

Supplemental Operating Experience Information for the Review of the Davis-Besse Nuclear Power Station, Unit No. 1 (Davis-Besse), License Renewal Application (LRA), Section B.2.19

Enclosure:

Amendment No. 58 to the Davis-Besse License Renewal Application cc: NRC DLR Project Manager NRC Region Ill Administrator cc: w/o Attachment or Enclosure NRC DLR Director NRR DORL Project Manager NRC Resident Inspector Utility Radiological Safety Board

Attachment L-15-192 Supplemental Operating Experience Information for the Review of the Davis-Besse Nuclear Power Station, Unit No. 1 (Davis-Besse),

License Renewal Application (LRA),

Section B.2.19 Page 1 of 2 On May 9, 2015, a Moisture Separator Reheater Drains System steam line failure occurred (ICES Report 316616) at an elbow, immediately downstream of a restricting orifice, on a 4-inch line in the Davis-Besse Turbine Building. The piping that failed is downstream from the Train 1 moisture separator reheater and second stage reheat drain tank, and is not within the scope of license renewal.

An extent-of-condition review and ultrasonic testing of the comparable elbow in the opposite train (Train 2) identified that the piping was below the piping standard minimum (87.5 percent nominal) wall thickness. The failed elbow and the degraded elbow were subsequently replaced. A review of the Flow-Accelerated Corrosion (FAC) Program modeling software, CHECWORKS SFA, identified that the reheat vent piping model contained incorrect orifice size data for both lines, which resulted in predicting a less-aggressive wear rate for the two elbows.

Further investigation was performed to determine if other incorrect information regarding restricting orifices (which includes flow elements) was contained in the CHECWORKS SFA database. This review identified other data entry errors. Of the 68 other orifices in the database:

• 27 orifices had dimensions in the database that required correction; o Correction of the dimensions for 6 of the 27 orifices resulted in changes in predicted wear rates that required additional investigation;

• Existing ultrasonic testing data was available for the piping downstream of four of the six orifices that confirmed fitness for service

• Ultrasonic testing was required prior to plant startup for the piping downstream of two of the six orifices, which confirmed fitness for service The modeled piping near orifices in the scope of the Flow-Accelerated Corrosion Program are not an operational or safety concern based on the extent-of-condition review and the testing performed.

It has been identified that incorrect input parameter data for the orifices had been entered into an earlier version of the FAC software in the 1987 to 1989 time frame and was carried forward to later versions. It has been further identified that corrective actions associated with the 2006 Train 1 moisture separator reheater first stage reheat

Attachment L-15-192 Page 2of2 drain line steam leak event did not include input parameter verification of restricting orifice data. Corrective actions are being taken to address both concerns.

Based on the steam line failure event and the issues identified during the investigation, LRA Table A-1, "Davis-Besse License Renewal Commitments," and Section B.2.19, "Flow-Accelerated Corrosion Program," Element 10, "Operating Experience," are revised to address the new operating experience described above.

See the Enclosure to this letter for the revision to the Davis-Besse LRA.

Enclosure Davis-Besse Nuclear Power Station, Unit No. 1 (Davis-Besse)

Letter L-15-192 Amendment No. 58 to the Davis-Besse License Renewal Application Page 1 of 6 License Renewal Application Sections Affected Table A-1 8.2.19 The Enclosure identifies the change to the License Renewal Application (LRA) by Affected LRA Section, LRA Page No., and Affected Paragraph and Sentence. The count for the affected paragraph, sentence, bullet, etc. starts at the beginning of the affected Section or at the top of the affected page, as appropriate. Below each section the reason for the change is identified, and the sentence affected is printed in italics with deleted text Jlned out and added text underlined.

Enclosure L-15-192 Page 2of6 Affected LRA Section LRA Page No. Affected Paragraph and Sentence Table A-1 A-69 New Commitment No. 55 In response to the steam line failure event of May 9, 2015, and the resulting Root Cause Evaluation Corrective Actions affecting the Flow-Accelerated Corrosion Program, LRA Table A-1, "Davis-Besse License Renewal Commitments," is revised to include new license renewal future Commitment 55, as follows:

Table A-1 Davis-Besse License Renewal Commitments Related LRA Item Implementation Commitment Source Section No./

Number Schedule Comments 55 Perform the following_ actions to imQ.rove and maintain the fidelit'i. of October 221 2016 FENOC A.1.19 the data in the Flow-Accelerated Corrosion Prog_ram: Letter B.2.19 L-15-192

• Perform a review of the CHECWORKS SFA model to determine which inQ.uts are critical to the determination of fitness for service and which inQ.uts are non-critical. This action will document the listing_ of all inQ.ut fields within the software 1 and whether their accurac'i_ affects the outQ.ut of the model.

• Perform a validation of the data inQ.uts into CHECWORKS SFA.

This task will include the validation of an'i. inQ.ut which would have conseg_uence 1 as used b'i. the CHECWORKS SFA software in the determination of fitness for service of Q.iping_ and comQ.onents for the Flow Accelerated Corrosion (FA Cl 12.rog_ram.

Data contained within the CHECWORKS SFA model that does not imQ.act fitness for service will be annotated during_ this validation as being_

Enclosure L-15-192 Page 3of6 Table A-1 Davis-Besse License Renewal Commitments Related LRA Item Implementation Commitment Source Section No./

Number Schedule Comments non-critical to the function of the software 1 while still atteme_ting to validate it.

• Document the results of the validation of the CHECWORKS SFA database. This action will create a document (Reference Materia/1 Program Manua/1 etc. l that will serve as a listing of ine.uts into the CHECWORKS SFA database and be maintained as a qualit'i_ record.

• Revise the CHECWORKS SFA model to correct the restriction orifices' size/dimension for the orifice and flow elements identified in the Steam Line Failure Root Cause Evaluation.

• Establish a list of come.onents for the site that meet the bulleted items within Section 4.4.4 of NSAC-202L 1 Revision 4.

Come.ile the inse.ection histort. of the relevant come.onents.

Perform an evaluation for an'{_ come.onents without inspection data 1 and add come.onents requiring inse.ection to 19RFO scoe.e. These locations are to se.ecificall'f. include:

0 Locations downstream of orifices1 flow elements 1 venturis 1 thermowells 1 angle valves 1 flow control valves or level control valves.

0 Locations or lines known to contain backing rings or counterbore.

0 Field-fabricated tees and laterals.

Enclosure L-15-192 Page 4 of 6 Table A-1 Davis-Besse License Renewal Commitments Related LRA Item Implementation Commitment Source Section No./

Number Schedule Comments 0 Nozzles.

0 ComQ/ex g_eometric locations such as components located within two diameters of each other (e.g_.z an elbow welded to a tee).

0 ComQonents downstream of reQlaced components (uQstream if exQanderlz and comQonents that have been reQlaced in the Qast if not UQg_raded to resistant material.

0 ComQonents (including_ straig_ht Qi£2.el immediatel'f.

downstream of FAG-resistant comQonents (e.g_. 1 containing_ chromium g_reater than 0. 10%1.

0 Locations immediatel'f. downstream of turning_ vanes.

0 ExQansion joints.

• Revise the Flow-Accelerated Corrosion Prog_ram £2.roCE~dure as follows:

0 Add requirements to the Qrocedure that would involve review and selection of examination scoQe based on recommendations from NSAC-202L 1 Rev 4 1 Section 4.4.4. This action requires documentation of the basis for selection or exclusion of the scoQe for the g_iven outag_e. Documentation would be in the

Enclosure L-15-192 Page 5 of 6 Table A-1 Davis-Besse License Renewal Commitments Related LRA Item Implementation Commitment Source Section No./

Number Schedule Comments form of discussion in the Outage Technical Re12.ort

(/2re-outag_el and Outage Summarv Re12.ort (post-outag_el.

0 Add a ste12. that would reg_uire review1 a12.12.roval1 and documentation of u12.dates to the CHECWORKS SFA database. The sco12.e of these changes would exclude data collected and evaluated during_

outag_es1 but would be inclusive of all others (such as 12.lant u12.rates 1 12.lant modifications1 engineering_

change 12.ackag_es1 etc.l. Documentation for this ste12.

would be through an Engineering_ Evaluation Reg_uest.

Enclosure L-15-192 Page 6 of 6 Affected LRA Section LRA Page No. Affected Paragraph and Sentence B.2.19 Page B-86 Operating Experience, 2nd Paragraph In response to the steam line failure event of May 9, 2015, LRA Section B.2.19, "Flow-Accelerated Corrosion Program," program element "Operating Experience",

2nd paragraph on LRA page B-86, is revised to read as follows:

In 2006, a steam leak was discovered on the moisture separator reheater 1 first stage reheat drain line that should have been detected by the Flow-Accelerated Corrosion (FAC) Program but resulted in a power reduction to facilitate repairs. Corrective actions associated with this event focused on separating modeled lines into single-phase and two-phase flow subsections.

but did not include input parameter verification of restricting orifices. The program was enhanced at that time to improve the documentation on quality of the software model and to include a second level of verification for entering data into CHECWORKS. Additionallv. a moisture separator reheater 1 second stage reheat vent line failed in May of 2015. resulting in a plant trip and forced outage. The failed elbow was confirmed by destructive examination to be a result of FAG. and the failure was attributed to a data entrv error discovered in the CHECWORKS SFA model. A restricting orifice immediately upstream of the failed elbow had its dimension incorrectly input into the original FAG computer model in the 1987 to 1989 time frame. Due to the error in the restricting orifice size. the model had predicted a less-aggressive wear rate from the inception of the FAG program. Corrective actions from this recent event include verification of all critical design inputs to the current CHECWORKS SFA model. enhancing the documentation requirements and approval process for changes to the CHECWORKS SFA model. and procedure updates for evaluating configurations known to accelerate wear in FAG-susceptible piping.