ENS 43903

From kanterella

Jump to navigation Jump to search

v t e ENS Event
21:12 Jan 13, 2008
Title	Failure of Uf6 Release Detection System
Event Description	At 1512 CST, on 01-13-08 the Plant Shift Superintendent (PSS) was notified that the C-333 Unit 6 Cell 7 UF6 Release Detection (PGLD) System failed to function when performing the twice per shift test firing. Test firing of the PGLD detector heads is required per TSR SR 2.4.4.1-1. TSR 2.4.4.1 also requires that at least the minimum number (three) of detector heads in the cell and in each defined section of the cell bypass are operable where UF6 systems are above atmospheric pressure. The C-333 Unit 6 Cell 7 PGLD System contains detectors that covers the cell and Sections 3 and 4 of the cell bypass piping. At the time of this failure some areas of Section 3 of the cell bypass were operating above atmospheric pressure. Since Unit 6 Cell 7 was operating below atmosphere, the cell was not in an applicable TSR mode. However, Section 3 of the cell bypass was above atmosphere and in an applicable TSR mode which required at least three operable PGLD heads. With the Unit 6 Cell 7 PGLD system inoperable only two of the required three heads in Section 3 of the cell bypass were operable. This PGLD System was declared inoperable, and system pressure in the affected operating area was reduced to less than atmospheric pressure within one hour, thus placing the operating system in a non-applicable TSR mode. This event is being reported as a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> event in accordance with 10CFR 76.120(c)(2)(i). This is an event in which equipment is disabled or fails to function as designed when: a.) the equipment is required by a TSR to prevent releases, prevent exposures to radiation and radioactive materials exceeding specified limits, mitigate the consequences of an accident, or restore this facility to a pre-established safe condition after an accident; b.) the equipment is required by a TSR to be available and operable and either should have been operating or should have operated on demand, and c.) no redundant equipment is available and operable to perform the required safety function. The NRC Resident Inspector has been notified of this event. PGDP Assessment and Tracking Report No. ATR-08-0122; PGDP Event Report No. PAD-2008-01; Worksheet No. 43903 Responsible Division: Operations The licensee is investigating the cause of the event, and will make appropriate notifications to the Department of Energy. * * RETRACTION PROVIDED BY TONY HUDSON TO JASON KOZAL AT 1403 ON 1/18/08 * * * On January 13, 2008 the C-333 U/6 C/7 PGLD system failed during testing. This affected all the PGLD heads in the cell area and two of the four heads in section 3 of the cell by-pass. A review of operating pressures in the affected area determined that the cell was operating below atmospheric pressure, but that piping in section 3 of the cell by-pass was operating above atmosphere. Thus, three of four heads in section 3 of the Cell by-pass were required by the TSR to be operable. Given the recent failure in November and indications that the failure modes may be similar, the PSS reported the event to the NRC per 10CFR 76.120(c)(2)(i), In-Service Safety System Failure. Subsequent to the event, the pressures in C-333 U/6 CR, section 3 in the cell by-pass area associated with the event were reviewed. Using Engineering Notice EN-C-821-05-090, Rev, 3, it was determined that section 3 of the cell by-pass was actually not operating above atmosphere and thus, the PGLD system was not required to be operable at the time of the failure. Since the failure only affected detectors in an area operating in a non-TSR mode, the PGLD system is not required to be operable and reporting under 10 CFR 76.120(C)(2) is not required. The licensee notified the NRC Resident Inspector. The licensee made appropriate notifications to the Department of Energy. R2DO (Moorman) and NMSS EO (Kokajko) notified.

ENS 43903 +/- *RETRACTED*
Where
Paducah Gaseous Diffusion Plant Paducah, Kentucky (NRC Region 2)
License number:	GDP-1
Reporting

10 CFR 76.120(c)(2)
Time - Person (Reporting Time:+18.4 h0.767 days <br />0.11 weeks <br />0.0252 months <br />)
Opened:	Tony Hudson 15:36 Jan 14, 2008
NRC Officer:	Joe O'Hara
Last Updated:	Jan 18, 2008
43903 - NRC Website
v • d • e

v t e Emergency Notification System
Paducah Gaseous Diffusion Plant with 10 CFR 76.120(c)(2)
WEEKMONTHYEAR2014-05-08T15:24:00 [Table view]
[ENS list for Paducah Gaseous Diffusion Plant]

Retrieved from "https://kanterella.com/w/index.php?title=ENS_43903&oldid=1184101"

ENS Notification