ENS 40079
ENS Event | |
|---|---|
16:45 Jun 30, 2003 | |
| Title | Troxler Moisture Density Gauge Run Over |
| Event Description | Licensee: WA State Dept. of Transportation (WA DOT), South Central Region
City and state: Yakima, Washington License number: WN-L065-1 Type of license: Portable Gauge Date of event: 30 June 2003 Location of Event: near Walla Walla, Washington ABSTRACT: (where, when, how, why; cause, contributing factors, corrective actions, consequences, DOH on-site investigation; media attention) On 30 June 2003, at about 9:45 AM, an errant motorist entered a coned-off lane and ran over a Troxler, Model 3430, moisture/density gauge, Serial Number 24671. The gauge contained two sealed sources, one of about 8 millicuries of Cesium 137 and the second of about 40 millicuries of Americium 241/Beryllium. The accident happened just north of Myra Road on State Route 125 near Walla Walla, Washington. An errant motorist drove past a WA DOT road flagger holding a stop sign. The motorist entered a lane that had been coned-off. The motorist proceeded to drive down the restricted lane and ran over the gauge while it was being used to test for compaction. The gauge operator saw the approaching vehicle and attempted to stop it by waving his hands and yelling as the vehicle approached. The motorist, a senior, was apparently oblivious to the lane restriction. After the gauge was hit, it wedged under the vehicle and was dragged for approximately 90 feet down the road until the motorist finally became aware of the problem and stopped. The cause was inattention or inability to understand that the road conditions had changed. It appears that age of the driver contributed to the cause of the event. The need to make any corrective action was deemed to be unnecessary. The gauge operator was operating per procedure and was only feet away from the gauge as it performed the test. The lane was restricted from travel by flagger and cone. The incident destroyed the gauge. Impact with the vehicle caused the Cesium 137 source to be drawn back into its shielded position. Although pieces of the gauge housing, electronics and mechanisms were scattered along the 90-foot section of road that the vehicle traveled after impact the gauge, the sources were still attached to their respective parts of the gauge. Subsequent leak tests were negative. DOH was not able to do an on site investigation due to the excessive distance to the event site and excessive time it would have taken to get staff to the site and clear the incident. The licensed RSO, a person trained to respond to events of this nature and having experience with similar events, went to the scene to give direction. The RSO performed surveys and an evaluation that allowed trained WA DOT personnel to release the area. The gauge parts were placed into the Troxler transportation box, a gravel/dirt mix was used to lower dose-rate readings to below a usual reading for an intact gauge, and the box was transported by trained WA DOT personnel to the WA DOT Headquarters facility for further evaluation, leak testing and disposition. WA DOH personnel performed an investigation of events and the gauge at WA DOT Headquarters after the gauge arrived. WA DOH staff inspected the gauge parts including the sources, evaluated the circumstances of the event, reviewed the report information, and consulted with WA DOT staff regarding procedure, equipment and their plan to return the gauge to Troxler. Once WA DOH staff determined that sources were not leaking and the material was safe to be returned to Troxler, it was sent to Troxler via normal method. There was no media attention. What is the notification or reporting criteria involved? 10 CFR 30.50(B)(2) and 20.2201 - After reviewing the incident file and the Handbook on Nuclear Material Event Reporting in the Agreement States , we determined that a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> notification should have been sent to NRC. This did not occur; consequently we are now submitting this completed report, although late. Activity and Isotope(s) involved: 8 millicuries of Cesium 137 and 40 millicuries of Americium 241/Beryllium Overexposures? (number of workers/members of the public; dose estimate; body part receiving dose; consequence) No members of the public received exposure in any amount. Calculation, survey readings and previous experience with similar gauge events indicate that WA DOT radiation worker staff only received exposure that is associated with usual gauge operations. Dosimetry reports will be evaluated upon receipt from the dosimetry processor. Lost, Stolen or Damaged? (mfg., model, serial number) Troxler, Model 3430, Serial Number 24671 was destroyed (damaged). Disposition/recovery: The gauge was returned to Troxler for disposal. Leak test? A leak test was performed on each source. They were found to be negative. Vehicle: (description; placards; Shipper; package type; Pkg. ID number) The gauge transportation vehicle was not involved in the event. Release of activity? There was no release of activity. Activity and pharmaceutical compound intended: N/A Misadministered activity and/or compound received: N/A Device (HDR, etc.) Mfg., Model; computer program: N/A Exposure (intended/actual); consequences: N/A Was patient or responsible relative notified? N/A Was written report provided? The licensee provided a written report, dated 7 July 2003. Was referring physician notified? N/A Consultant used? No |
| Where | |
|---|---|
| Wa Dot Yakima, Washington (NRC Region 4) | |
| License number: | WN-L065-1 |
| Organization: | Wa Division Of Radiation Protection |
| Reporting | |
| Agreement State | |
| Time - Person (Reporting Time:+1110.4 h46.267 days <br />6.61 weeks <br />1.521 months <br />) | |
| Opened: | Scroggs 23:09 Aug 15, 2003 |
| NRC Officer: | John Mackinnon |
| Last Updated: | Aug 15, 2003 |
| 40079 - NRC Website | |
Wa Dot with Agreement State | |
WEEKMONTHYEARENS 400792003-06-30T16:45:00030 June 2003 16:45:00
[Table view]Agreement State Troxler Moisture Density Gauge Run Over 2003-06-30T16:45:00 | |