ML12244A029
| ML12244A029 | |
| Person / Time | |
|---|---|
| Site: | Braidwood, Cook, Comanche Peak  |
| Issue date: | 09/11/2012 |
| From: | Eric Benner NRC/NMSS/SFST/LID/RIOB |
| To: | Leblang S Entergy Services |
| Benner J | |
| References | |
| Download: ML12244A029 (2) | |
Text
September 11, 2012 Ms. Suzanne Leblang, Chair Holtec Users Group Entergy Services Inc.
1340 Echelon Parkway, M-ECH-36 Jackson, MS 39211
SUBJECT:
DRAIN AND VENT PORT CAP ISSUES
Dear Ms. Leblang:
Recently, the U.S. Nuclear Regulatory Commission (NRC) inspection staff has become aware of several issues with drain and vent port caps used on Holtec spent fuel storage systems which have impacted dry cask storage loading activities. At Comanche Peak, a stuck drain port cap prevented the licensee from completing the helium backfill of the canister. The stuck drain port cap was successfully removed, but in the process the threads on the drain line were damaged, requiring them to be reconditioned. Additionally at Braidwood, a leaking gasket/o-ring on the vent port cap required the licensee to remove the cap and clean the threads before continuing.
Most recently at DC Cook, the licensee experienced one stuck drain port cap and a second with increased resistance. The NRC is also aware that Holtec has issued several communications to users of its systems regarding issues with these drain and vent port caps.
While each issue mentioned above was able to be resolved and dry cask loading activities continued, we believe the repetitive nature of the issues represents a potential trend that warrants increased attention. Could you please provide what actions the Holtec Users Group1 and licensees have, or are planning, to take in response to these recent issues? Such information will assist us in determining whether any generic NRC action is warranted and will allow us to better focus future inspection and licensing activities.
Sincerely,
/RA/
Eric J. Benner, Chief Rules, Inspections & Operations Branch Office of Nuclear Material Safety and Safeguards cc: Stefan Anton, Holtec 1 The Holtec Users Group consists of member utilities who have a contract with Holtec International for spent fuel storage cask systems.
Ms. Suzanne Leblang, Chair Holtec Users Group Entergy Services Inc.
1340 Echelon Parkway, M-ECH-36 Jackson, MS 39211
SUBJECT:
DRAIN AND VENT PORT CAP ISSUES
Dear Ms. Leblang:
Recently, the U.S. Nuclear Regulatory Commission (NRC) inspection staff has become aware of several issues with drain and vent port caps used on Holtec spent fuel storage systems which have impacted dry cask storage loading activities. At Comanche Peak, a stuck drain port cap prevented the licensee from completing the helium backfill of the canister. The stuck drain port cap was successfully removed, but in the process the threads on the drain line were damaged, requiring them to be reconditioned. Additionally at Braidwood, a leaking gasket/o-ring on the vent port cap required the licensee to remove the cap and clean the threads before continuing.
Most recently at DC Cook, the licensee experienced one stuck drain port cap and a second with increased resistance. The NRC is also aware that Holtec has issued several communications to users of its systems regarding issues with these drain and vent port caps.
While each issue mentioned above was able to be resolved and dry cask loading activities continued, we believe the repetitive nature of the issues represents a potential trend that warrants increased attention. Could you please provide what actions the Holtec Users Group2 and licensees have, or are planning, to take in response to these recent issues? Such information will assist us in determining whether any generic NRC action is warranted and will allow us to better focus future inspection and licensing activities.
Sincerely,
/RA/
Eric J. Benner, Chief Rules, Inspections & Operations Branch Office of Nuclear Material Safety and Safeguards cc: Stefan Anton, Holtec 1 The Holtec Users Group consists of member utilities who have a contract with Holtec International for spent fuel storage cask systems.
Distribution: J. Goshen M. Waters D. Weaver M. Lombard E. Benner ADAMS P8 Accession No.: ML12244A029 OFC SFST SFST NAME WWheatley EBenner DATE Via e-mail 9/10/12 9/11/12