ML20137V762
| ML20137V762 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 02/12/1986 |
| From: | NRC |
| To: | |
| Shared Package | |
| ML20137V753 | List: |
| References | |
| GL-84-11, NUDOCS 8602190714 | |
| Download: ML20137V762 (1) | |
Text
UNITED STATES o,
NUCLEAR REGULATORY COMMISSION
[
j W ASHINGTON, D. C. 20555 5
p
\\...../
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGU SUPPORTING PARTIAL RELIEF FROM PERFORMING VISUAL EXAMIN OF REACTOR COOLANT PIPING PILGRIM NUCLEAR POWER STATION DOCKET NO. 50-293
1.0 INTRODUCTION
25, 1985, The licensee (Boston Edison Company) in its submittal dated November requested relief from the visual examination requirements in Generic Letter Item E in Attachment I to GL 84-11 requires the licensee to (GL) 84-11.
enter the containment and perform a visual examination for leakage of the reactor coolant piping whenever the containment is de-inerted.
2.0 EVALUATION The requirement that visual inspection for leakage be performed between scheduled outages was imposed to augment the installed leakage detection It reflects staff concerns regarding the sensitivity of leak systems.
detection systems based primarily on sump level monitoring.
Most of the piping at Pilgrim Station has been replaced with type 316NG Although not all which is expected to be more resistant to IGSCC.
susceptible piping was repisced, the licensee did inspect essentially all remaining old welds, so the probability of developing leaks or significant cracks has been significantly reduced.
a
3.0 CONCLUSION
We conclude that visual inspection of the Pilgrim Station piping should not be required at intervals of less than 3 months (92 days) of operation, for the following reasons:
Most of the piping has been replaced with resistant material.
1.
The remaining IGSCC susceptible piping welds have been essentially 2.
100% inspected and no significant cracking was found.
~ The additional personnel exposure associated with multiple exam-inations at a frequency less than 3 months is not justified.
3.
Prinicipa} Reviewer:
W. Koo.
Dated: February 12, 1986.
I i
B602190714 860212 PDR ADOCK 05000293 P
- .