ML12200A209
| ML12200A209 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 11/17/2011 |
| From: | Hernandez P Plant Licensing Branch III |
| To: | Sanchez-Santiago E NRC/RGN-III |
| References | |
| FOIA/PA-2012-0121 | |
| Download: ML12200A209 (1) | |
Text
He!bandgz, Pete UNITED STATES 0-
"NUCLEAR REGULATORY COMMISSION
- o0 \\,Hernandez, Pete \\ WASHINGTON, D.C. 20555-0001
\\
Thursday, November 17, 2011 7:58 AM
- Sanchez Santiago, Elba S-Ad'je.
SrF Davis Besse Operability question Good afternoon Michele, I understand that the question of Operability vs design basis was posed~and that if ti& issue VQ.Ain operations space, are qualitative evaluations the extent of review required by the licensee?
To answer that, the distinction between Operability and Functionality needs to be understood. The most clear way I've had it explained is that the determination of Operability is tied to the Tech Specs for the specific plant.
If the Tech Specs are met, then it is operable. (An operability determination is usually prompted by degraded conditions, nonconforming conditions or the discovery of an unanalyzed condition.) Functionality is tied to the design bases documented in the FSAR and thereby tied to the Current Licensing Basis.
From IMC9900 "If an SSC described in TSs is determined to be operable even though a degraded or nonconforming condition is present, the SSC is considered "operable but degraded or nonconforming." An SSC that is determined to be operable but degraded or nonconforming is considered to be in compliance with its TS LCO, and the operability determination is the basis for continued operation. The basis for continued operation should be frequently and regularly reviewed until corrective actions are successfully completed."
The licensee decided to not enter into an Operable but Degraded or Nonconforming determination and that the cracking issue is a design basis question hence functionality.
Speculating: The cracks in the building qualify as an unanalyzed condition so for the licensee to Operate with a degraded or nonconforming condition, they would have to develop a plan to fix the issue through their CA process. However, the licensee has stated that the SB is Operable as is, so there is nothing to fix. This still leaves the issue of the cracks unresolved so they are trying to prove that the cracks do not affect the functionality of the building. This led them to the design basis evaluations.