ML12108A062

NRR E-mail Capture - Quad Cities Unit 2 Relief Request I4R-19 - Followup Question to Response to RAI Question 8

ML12108A062
Person / Time
Site:	Quad Cities
Issue date:	04/13/2012
From:	Joel Wiebe Division of Operating Reactor Licensing
To:	Gullott D, Bauer J, Mathews M Exelon Generation Co
References
RS-12-069
Download: ML12108A062 (2)

Text

NRR-PMDAPEm Resource From: Wiebe, Joel Sent: Friday, April 13, 2012 2:09 PM To: 'David Gullott'; 'Joseph Bauer'; 'Mitchel Mathews'

Subject:

Quad Cities Unit 2 Relief Request I4R Followup Question to Response to RAI Question 8

REQUEST FOR ADDITION INFORMATION RELATED TO CORROSION EVALUATION OF THE QUAD CITIES UNIT 2 N-11B REACTOR VESSEL NOZZLE MODIFICATION, ATTACHMENT 2 TO LETTER RS 069 With respect to general and galvanic corrosion of low-alloy steel, the licensee corrosion evaluation, provided as Attachment 2 to Letter RS-12-069 dated April 12, 2012, references NECD-21120, Monticello Feedwater Nozzle Cladding Crack Repair Report, as the basis for low general corrosion rates and the absence of galvanic corrosion. The licensees corrosion evaluation references D.C. Vreeland, et. Al., Corrosion of Carbon and Low-Alloy Steels in Out-of-Pile Boiling Water Reactor Environment, Corrosion, Vol. 17, No. 6, 1961, as the basis for minimal crevice corrosion of low alloy steel in a boiling water reactor (BWR) operating environment.

Requested Information To ensure these two references provide bounding corrosion rates for Quad Cities, Unit 2, compare the chemistry of the steam or water to which the low-alloy steel in the repaired N-11B nozzle will be exposed (in the gap between the nozzle remnant and new nozzle) to the chemistry used in the tests described in the two references discussed above. The specific parameters to be addressed should include the concentration of dissolved oxygen and impurities such as chloride and sulfate, conductivity, hydrogen, electrochemical corrosion potential (ECP), and any other parameters that may affect corrosion rates. Values of the parameters for Quad Cities may be typical or average values or maximum values. If the steam/water environment tests documented in the references do not envelop or bound the actual conditions to which the low-alloy steel in Nozzle N-11B will be exposed, provide a justification for the use of these reference to support the prediction of minimal corrosion for the exposed low-alloy steel, or provide additional references.

1

Hearing Identifier: NRR_PMDA Email Number: 336 Mail Envelope Properties (F371D08C516DE74F81193E6D891DC4AF8E60AC2090)

Subject:

Quad Cities Unit 2 Relief Request I4R Followup Question to Response to RAI Question 8 Sent Date: 4/13/2012 2:08:34 PM Received Date: 4/13/2012 2:08:00 PM From: Wiebe, Joel Created By: Joel.Wiebe@nrc.gov Recipients:

"'David Gullott'" <David.Gullott@ExelonCorp.com>

Tracking Status: None

"'Joseph Bauer'" <Joseph.Bauer@exeloncorp.com>

Tracking Status: None

"'Mitchel Mathews'" <Mitchel.Mathews@exeloncorp.com>

Tracking Status: None Post Office: HQCLSTR02.nrc.gov Files Size Date & Time MESSAGE 1922 4/13/2012 2:08:00 PM Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received: