ENS 49689
ENS Event | |
|---|---|
20:30 Jan 2, 2014 | |
| Title | Fixed Source Shielding Failure |
| Event Description | This letter is a follow up to our phone conversation dated January 2, 2014, with a contact time of 2041 EST which involved damage to one of our fixed nuclear sources (Model TN5200 s/n B3493). This report is being filed in compliance to 10 CFR 30.50(b)(2)(ii).
On January 2, 2014, on or about 1535 pm CST it was noted that the shell of our #2 cupola had overheated during startup of the equipment. Previously at 1130 CST, the shell temperature was noted at 145 degrees F. At the time of the event, the shell temperature was noted at 990 degrees F. The person taking the temperatures was using a hand held laser temperature device and took the temperature remote to the shell. The person taking the temperatures immediately contacted a Radiation Safety Officer (RSO). The RSO then conducted a visual inspection of the gauge and noted a puddle in front of the gauge. All personnel were evacuated from the vicinity of the cupola shell. An additional RSO was contacted at 1602 CST via phone. He then proceeded to conduct an evaluation of the area at approximately 1630 CST. The nuclear source noted above is used to measure scrap metal level in the cupola and is located directly against the cupola shell, down in an enclosed moat. This in turn resulted in the high ambient temperatures causing the lead shielding of the nuclear source to melt out the front of the gauge. The amount of lead melted out is estimated to be the equivalent of shot glass. The manufacturer of the gauge was contacted at 1732 CST and informed of the event. The RSO will contact the manufacturer again tomorrow during normal business hours to arrange for the removal and replacement of the gauge. The gauge is a Thermal Fisher Model TN5200, serial number B3493 containing Cs-137 with an activity of 100 mCi. The evaluation of the gauge was compared to survey readings previously taken on September 14, 2013 by the RSO in conjunction with the required six month inventory requirements. Survey readings conducted this evening were done using a Ludlum Model 3 calibrated on December 20, 2013. There were no over exposures during this event due to the remote reading of the temperature and the quick evacuation of the area. Follow up surveys did note an area by the receiver of the damaged gauge (approximately 21 feet away) to be 0.4 mR which is higher than the previous reading in September of 0.1 mR. Crews were instructed to not enter the moat nor attempt to repair the receiver due to the inability to lock out the shutter at this time. All other areas noted in the vicinity of the gauge as well as above and below the gauge were the same as or below the September readings. The cause of the event as to the shell overheating will be further investigated tomorrow, January 3, 2014. The results of the investigation will be included in a letter within 30 days to [U.S.NRC] Region Ill. |
| Where | |
|---|---|
| Waupaca Foundry Tell City, Indiana (NRC Region 3) | |
| License number: | 48-15031-01 |
| Organization: | Waupaca Foundry |
| Reporting | |
| 10 CFR 30.50(b)(2), Licensed Material Protection Equipment Failure | |
| Time - Person (Reporting Time:+0.18 h0.0075 days <br />0.00107 weeks <br />2.46564e-4 months <br />) | |
| Opened: | Gary Greubel 20:41 Jan 2, 2014 |
| NRC Officer: | Mark Abramovitz |
| Last Updated: | Jan 2, 2014 |
| 49689 - NRC Website | |
Waupaca Foundry with 10 CFR 30.50(b)(2) | |
WEEKMONTHYEARENS 496892014-01-02T20:30:0002 January 2014 20:30:00
[Table view]10 CFR 30.50(b)(2) Fixed Source Shielding Failure 2014-01-02T20:30:00 | |