ML042820564
| ML042820564 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 10/06/2004 |
| From: | NRC/NRR/DLPM |
| To: | |
| SHUKLA G , NRR/DLPM/PD4, 415-8420 | |
| Shared Package | |
| ML042860206 | List: |
| References | |
| TAC MC1647, TAC MC1648 | |
| Download: ML042820564 (1) | |
Text
Programs and Manuals 5.5 5.5 Programs and Manuals 5.5.9 Steam Generator (SG) Tube Surveillance Program (continued)
(iv) Certain intersections as identified in PG&E Letter DCL-03-174, dated December 19, 2003, will be excluded from application of the voltage-based repair criteria as it is determined that these intersections may collapse or deform following a postulated LOCA + SSE event.
(v) If an unscheduled mid-cycle inspection is performed, the following mid-cycle repair limits apply instead of the limits identified in 5.5.9.d.1.j (i), 5.5.9.d.1.j (ii), and 5.5.9.d.lj (iii). The mid-cycle repair limits are determined from the following equations:
VSL VMURL (CVSL (CL-A 1.0 + NDE + Gr CL CL VMLRL = VMURL - (VURL -
VLRL) (C At)
CL where:
VURL
= upper voltage repair limit VLRL
= lower voltage repair limit VMURL = mid-cycle upper voltage repair limit based on time into cycle VMLRL = mid-cycle lower voltage repair limit based on VMURL and time into cycle At
= length of time since last scheduled inspection during which VURL and VLRL were implemented CL
= cycle length (the time between two scheduled steam generator inspections)
VSL
= structural limit voltage Gr
= average growth rate per cycle length NDE
= 95% cumulative probability allowance for nondestructive examination uncertainty (i.e., a value of 20% has been approved by the NRC)
Implementation of these mid-cycle repair limits should follow the same approach as in TS 5.5.9.d.1.j (i), 5.5.9.d.1lj (ii), and 5.5.9.d.1lj (iii).
(continued)
DIABLO CANYON - UNITS 1 & 2 5.0-14 Unit 1 -Amendment No. 435,176 8S9IDQ10.doc-RXX 16 Unit 2 -Amendment No. 435,178