**TI 2515/171, APPENDIX C**

**B.5.b SIGNIFICANCE DETERMINATION PROCESS**

I OBJECTIVE

The objective of this SDP is to accommodate all potential greater than
minor B.5.b inspection findings identified during the implementation of
Temporary Instruction (TI) 2515/171 - VERIFICATION OF SITE SPECIFIC
IMPLEMENTATION OF B.5.B PHASE 2 & 3 MITIGATING STRATEGIES. The TI's
objective is to verify and confirm licensee's implementation of B.5.b
mitigating strategies required by license conditions issued to existing
commercial nuclear power reactors in July - August 2007. The strategies
for each licensee were reviewed by the staff who issued a safety
evaluation report (SER) to document the commitments to implement these
strategies. The site specific responses delineating each licensee's
commitment and the SERs are listed in Exhibit 1 of the TI.

II ENTRY CONDITIONS

Each issue entering the SDP process must first be screened to determine
its documentation threshold (i.e. if more than minor in significance)
using Inspection Manual Chapter (IMC) 0612, Appendix B, "Initial
Screening." Issues screened as minor are not subjected to further SDP
screening**.**

III DEFINITIONS

B.5.b event -- a beyond design basis loss of a large area of a reactor
plant due to fires or explosions initiated by a terrorist threat as
stated in Attachment 2 to order EA-02-026.

Unrecoverable -- an unavailable mitigating strategy is unrecoverable if
licensee actions could neither reasonably correct nor compensate for the
conditions creating the unavailability in time during a B.5.b event for
the mitigating strategy to achieve its objective. The time limit is the
time allowed by NEI 06-12 for establishment of the strategy where
applicable, or a reasonable time.

Unavailability -- a mitigating strategy is unavailable if its hardware
or components are not functional and ready for intended use, or
personnel training and procedures are inadequate, as described in the
licensee submittal and SER supporting the B.5.b license condition.

Refer to the definitions listed in TI-2515/171 Appendix A -- General
Guidance and Definitions

IV GUIDANCE

Record the performance deficiency and factually describe known
observations associated with the deficiency in Table 1 - SDP Screening
Worksheet for TI-2515/171. Evaluation of the listed attributes may be
informative in determining the significance of the finding. Consider
only attributes which relate directly to the significance of the finding
and document the basis for the consideration. If Table 1 is used to
document a performance deficiency and the factual description of the
condition, the table will be properly labeled as Official Use Only --
Security Related Information.

  -------------------------- --------------------------------------------
  **TABLE 1 -- SDP Screening 
  Worksheet for              
  TI-2515/171**              

  **Inspection Report \#**   

  **Performance Deficiency** 
  (concise statement clearly 
  stating the deficient      
  licensee performance)      

  **Factual Description of   
  Condition** (facts about   
  the condition that         
  resulted from the          
  performance deficiency     
  without hypothetical       
  failures included)         

  **Systems/Trains Degraded  
  by Condition or            
  Programmatic Weakness**    
  (list the Hardware,        
  Procedures or Training)    

  **Extent of Condition**    
  (describe what other       
  strategies are directly    
  affected by the            
  deficiency)                

  **Exposure Time** (Period  
  of time the performance    
  deficiency existed; and if 
  opportunity to identify    
  the finding during such    
  period was missed          
  (operating experience,     
  licensee=s programs such   
  as surveillance testing)   

  **Recovery** (The          
  likelihood that the        
  licensee=s recovery        
  actions would successfully 
  mitigate the performance   
  deficiency)                
  -------------------------- --------------------------------------------

The examples provided for each level of significance in Table 2 serve as
guidance in determining the appropriate characterization for findings;
however, they are neither exhaustive nor controlling. The
characterization of each finding is dependent on the circumstances of
the issue defined in Table 1. In addition, these examples do not create
new requirements. Each is intended to illustrate the significance that
the NRC places on a particular type of finding. Each potential finding
must be considered on its own merits to ensure that its significance is
characterized at the level best suited to the circumstances using
qualitative engineering judgment and regulatory oversight experience in
each case. This is necessary because the examples provided are
intentionally limited to deter a mechanistic approach or unreasoned
conclusion. With this in mind, the entire spectrum of characterizations
should be considered with the particular finding placed in context in
consideration of its particular circumstances. The appropriate
cornerstone for a finding will be determined using table 2 of IMC
0609.04.

+--------+-------------------------------------------------------------+
| *      |                                                             |
| *TABLE |                                                             |
| 2 --   |                                                             |
| Signif |                                                             |
| icance |                                                             |
| Charac |                                                             |
| teriza |                                                             |
| tion** |                                                             |
+--------+-------------------------------------------------------------+
| **G    | Unrecoverable unavailability of any individual mitigating   |
| REEN** | strategy.                                                   |
+--------+-------------------------------------------------------------+
| **W    | 1\. Unrecoverable unavailability of multiple mitigating     |
| HITE** | strategies such that SFP cooling, injection to RPV, or      |
|        | injection to SGs cannot occur, or                           |
|        |                                                             |
|        | 2\. Unrecoverable unavailability of on-site, self powered,  |
|        | portable pumping capability, or                             |
|        |                                                             |
|        | 3\. Substantial inability to perform Command and Control    |
|        | Enhancements.                                               |
+--------+-------------------------------------------------------------+
|        | Examples:                                                   |
|        |                                                             |
|        | \- Unrecoverable unavailability of injection to the reactor |
|        | vessel or steam generators (concurrent unavailability of    |
|        | low pressure pumping/depressurization strategies and        |
|        | unavailability of manual operation of RCIC/Isolation        |
|        | Condenser or turbine (or diesel) driven AFW)                |
|        |                                                             |
|        | \- Unrecoverable unavailability of SFP internal strategy,   |
|        | SFP external fill strategy, AND SFP external spray strategy |
|        |                                                             |
|        | \- Substantial inability to perform Command and Control     |
|        | Enhancements                                                |
+--------+-------------------------------------------------------------+
| **YE   | A failure to substantially establish mitigating strategies  |
| LLOW** | in one or more of the following overall mitigating          |
|        | strategies areas:                                           |
+--------+-------------------------------------------------------------+
|        | \- Fire fighting response strategies                        |
|        |                                                             |
|        | \- Operations to mitigate reactor core fuel damage          |
|        | including command and control and actions to minimize       |
|        | release                                                     |
|        |                                                             |
|        | \- Operations to mitigate Spent Fuel Pool fuel damage       |
|        | including command and control and actions to minimize       |
|        | release                                                     |
+--------+-------------------------------------------------------------+
| *      | In an actual B.5.b event, a substantial failure of          |
| *RED** | mitigating strategies to function as intended (i.e. achieve |
|        | the strategies' objectives) in one or more of the following |
|        | overall mitigating strategies areas:                        |
+--------+-------------------------------------------------------------+
|        | \- Fire fighting response strategies                        |
|        |                                                             |
|        | \- Operations to mitigate reactor core fuel damage          |
|        | including command and control and actions to minimize       |
|        | release                                                     |
|        |                                                             |
|        | \- Operations to mitigate Spent Fuel Pool fuel damage       |
|        | including command and control and actions to minimize       |
|        | release                                                     |
+--------+-------------------------------------------------------------+

ATTACHMENT 1

Revision History For TI 2515/171, Appendix C

B5b Significance Determination Process

+--------+--------+--------------------+-----+----------+-------------+
| Comm   | Issue  | Description of     | Tr  | Training | Comment     |
| itment | Date   | Change             | ain | Co       | Resolution  |
| Tr     |        |                    | ing | mpletion | Accession   |
| acking |        |                    | Nee | Date     | Number      |
| Number |        |                    | ded |          |             |
+--------+--------+--------------------+-----+----------+-------------+
| N/A    | 05     | Revision history   | N/A | N/A      | ML081200042 |
|        | /16/08 | reviewed for the   |     |          |             |
|        |        | last four years -  |     |          |             |
|        | CN     | no generic         |     |          |             |
|        | 08-015 | requirements       |     |          |             |
|        |        | incorporated       |     |          |             |
|        |        | during this        |     |          |             |
|        |        | period.            |     |          |             |
+--------+--------+--------------------+-----+----------+-------------+
|        |        |                    |     |          |             |
+--------+--------+--------------------+-----+----------+-------------+