ENS 48015
ENS Event | |
|---|---|
04:00 Jun 5, 2012 | |
| Title | Previously Stolen Source Holder Located in a Scrap Yard |
| Event Description | The following information was received by facsimile:
On June 5, 2012, US NRC Region I communicated with [Caribbean Marine Contractors, Corp] to notify that Ronan Measurement RLL-1 SN #206762A registered on behalf of Caribbean Marine Contractors had been found in a scrap yard in Taiwan. Immediately, we started doing our investigations to verify whether the RLL-1 found in Taiwan was ours. We proceeded to look in our storage container for the RLL-1. Noticing the absence of RLL-1, we talked to company personnel who regularly entered the storage container and everyone questioned arrived at this conclusion. Approximately two years ago, Caribbean Marine was doing work of dredging in the town of Guayama, PR. We stopped the work of dredging and we were doing preventive maintenance to the marine equipment (washing with fresh water, removing rust, paint, etc.). [A manager] who at that time was in charge of the project gave the order to take the RLL-1 that was not working out of the dredge and store it in the storage container of the project. Weeks later, thieves broke in the container and stole the metals that were inside. Usually metals lead them to recycling centers and sold by weight. These recycling centers in turn sold the material to Taiwan or India. That [is the] way we understand that you found the RLL-1 #206762A in Taiwan. The Ronan ultra-low level series of source holders (RLL) use very small quantities of radioactive materials. The RLL-1 is permitted to contain to a maximum of 900 microCuries of cesium-137 or 200 microCuries cobalt-60. The radioactive material is completely encapsulated in a stainless steel capsule, which is then heli-arc or laser welded closed. Due to high structural integrity, these source capsules qualify as special material form; virtually eliminating the possibility of the spread of radioactive contaminant. The sealed capsules are loaded into the RLL-1 device. This is a stainless steel tube that is welded shut at both ends and installed inside a shielded, steel housing. The general licensee is not permitted to repair, modify, or otherwise tamper with the device or its shielding. The combination of high structural integrity and low source quantity permits the general licensee to install and commission the device without special training or certification. The general licensee is required to install and operate the gage in accordance with the instructions provided by Ronan Engineering. The RLL-1 device is not required to be wipe tested and there is no shutter or moving parts that have to be periodically inspected or maintained. Important Exception The RLL-1 device is required to be tested every three years if it contains a single wipe capsule in excess of 100 microCuries. If a leak test is required, to stainless steel tag will be permanently affixed to the device stating. 'Leak Test Required'. Iso distance curves are provided in this manual for various applications as specified in the table below: Application Drawing Number Weight Gages C-16307-K and C-16310-K Continuous Level Gages B-16306-K and C-16309-K Density / Point Level Gages B-16305-K and B-16308-K These curves indicate that the maximum dose rate, at one foot, from any device is less than 0.5 mR/h. Most of these devices require (as a conservative estimate) less than 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> of handling to install. Based upon these low dose rates and the short period of time required for handling/installation it is unlikely that any personnel would receive a significant exposure. In fact, it can be safely assumed that working personnel will receive considerably less than 10 percent (10%) of the dose limits specified in column IV of 10 CFR 32.24, for the appropriate organs, and less than ten percent of the dose limits specified in 10 CFR 20.1201(a). THIS MATERIAL EVENT CONTAINS A "LESS THAN CAT 3" LEVEL OF RADIOACTIVE MATERIAL Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf This source is not amongst those sources or devices identified by the IAEA Code of Conduct for the Safety & Security of Radioactive Sources to be of concern from a radiological standpoint. Therefore is it being categorized as a less than Category 3 source THIS MATERIAL EVENT CONTAINS A "NOT RECORDED" LEVEL OF RADIOACTIVE MATERIAL |
| Where | |
|---|---|
| Caribbean Marine Contractors, Corp Trujillo Alto, Puerto Rico (NRC Region 1) | |
| Organization: | Caribbean Marine Contractors, Corp |
| Reporting | |
| 10 CFR 20.2201(a)(1)(ii) | |
| Time - Person (Reporting Time:+172.55 h7.19 days <br />1.027 weeks <br />0.236 months <br />) | |
| Opened: | Alfonso Diaz 08:33 Jun 12, 2012 |
| NRC Officer: | Dong Park |
| Last Updated: | Jun 12, 2012 |
| 48015 - NRC Website | |
Caribbean Marine Contractors, Corp with 10 CFR 20.2201(a)(1)(ii) | |
WEEKMONTHYEARENS 480152012-06-05T04:00:0005 June 2012 04:00:00
[Table view]10 CFR 20.2201(a)(1)(ii) Previously Stolen Source Holder Located in a Scrap Yard 2012-06-05T04:00:00 | |