ML091490363
| ML091490363 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 05/06/2009 |
| From: | Engineering Region 1 Branch 1 |
| To: | |
| References | |
| FOIA/PA-2009-0070 | |
| Download: ML091490363 (2) | |
Text
Exec Summary of Inspection Results
" Observed actions to evaluate primary containment structural integrity
" Observed selected activities described in SER Appendix-A, "Commitments for LR" Because the License has not been renewed 9 Observed activities will be documented (i.e., factual based observations)
- No assessment was made regarding implementation of SER described activities
- e.g., no conclusions whether proposed commitments were implemented 9 No assessment or evaluation of activity effectiveness or adequacy was made 9 No safety assessment of the observed activities described in SER App-A was made
" Reviewed 2 change packages for activities described in SER App-A
" A summary of the change will be documented
- No assessment of administrative controls was made
- No evaluation of technical adequacy was made
- An Unresolved Item (URI) will be opened to evaluate whether existing current licensing basis commitments were not adequately performed, and to assess the safety significance for any related performance deficiency
Inspection Report Outline (1) SER App-A Item 27, ASME Section XI, Subsection IWE, Part (2)
A strippable coating will be applied to the reactor cavity liner to prevent water intrusion into the gap between the drywell shield wall and the drywell shell during periods when the reactor cavity is flooded.
- From Oct 29 to Nov 7, the strippable coating limited leakage into the cavity trough drain at < 1 gpm
- On Nov 7, the observed leakage rate in the cavity trough drain took a step change to 4 to 6 gpm
- Water was subsequently identified in 4 sand bed bays
- AmerGen identified several likely or contributing causes:
- A portable water filtration unit was improperly placed in the reactor cavity, which resulted in flow discharged directly on the strippable coating
" An oil spill into the cavity may have affected the coating integrity
" No post installation inspection of the coating had been performed
- AmerGen stated follow-up UTs will re-evaluate the drywell shell next outage.
(2) SER App-A Item 27, ASME Section XI, Subsection IWE, Part (3)
Sand bed region drains will be monitored daily during refueling outages.
- Sand bed drains were remotely monitored by checking poly bottles, attached via tygon tubing to funnels hanging below the drain lines
- The drain lines were not directly observed
- After the reactor cavity was drained, 2 of 5 tygon tubes were found disconnected, laying on the floor
- Sand Bed Bay 11 drain line poly bottle was empty during each daily check until Nov 15 (cavity was drained on Nov 12), when it was found full (> 4 gallons). Bay 11 was entered, visually inspected, and found dry.
(3) SER App-A Item 27, ASME Section XI, Subsection IWE, Part (3)
Reactor cavity seal leakage trough drains and the drywell sand bed region drains will be monitored for leakage. Periodically.
- Cavity trough drain line was found isolated during a boroscope examination to verify no line blockage
- On Oct 27, the drain line was isolated to install a tygon hose to allow drain flow to be monitored
- On Oct 29, the reactor cavity was filled
- AmerGen monitored the drain line monitored during cavity flood-up, and daily thereafter
- On Oct 31, a boroscope examination identified the drain line isolation valve had been left closed
- When the drain line isolation valve was opened, about 3 gallons of water drained out, then the drain flow subsided to about an 1/8 inch stream (< 1 gpm) e Drain flow remained at < 1 gpm until Nov 7, the strippable coating started to de-laminate