PNO-IV-99-045, on 991020,employee of Morrison-Knudsen Notified NRC Region IV Ofc of Incident Involving Destruction of Troxler Portable Moisture Density Gauge 4300 Series.Gauge Was Owned & Operated by MSE-HKM,Inc,subcontractor
| ML20217J619 | |
| Person / Time | |
|---|---|
| Site: | 03012845 |
| Issue date: | 10/21/1999 |
| From: | Cruz J, Linda Howell NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| References | |
| PNO-IV-99-045, NUDOCS 9910250121 | |
| Download: ML20217J619 (1) | |
October 21,1999
. PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE PNO-IV-99-045 This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. The information is as initially j receiyed without verification or evaluation, and is basically all that is '
known by Region IV staff in Arlington, Texas on this date.
Facility - Licensee Emeroency Classification Mse-Hkm, Inc. Notification of Unusual Event Mse-Hkm,' inc. Alert P.O. Box 31318 Site Area Emergency Billings, Montana 59107 _
General Emergency Dockets: 03012845 License No: 25-17492-01 X Not Applicable l
Subject:
DAMAGE TO A PORTABLE MOISTURE DENSITY GAUGE, CODY, WY On October 20,1999, an employee of Morrison-Knudsen (the primary contractor for a l highway construction project near Ccdy, WY) notified the NRC Region IV office of an incident involving the destruction of a Troxler portable moisture density gauge (3400 Series). The gauge was owned an operated by MSE-HKM, Inc. (licensee), a subcontractor to Morrison-Knudson on this construction project.
The licensee's representative reported that after completing measurements on fresh asphalt paving, a truck carrying a load of aggregate inadvertently drove onto the new pavement, in the west bound lane of US 14/16 (State Highway 20), and ran over the moisture density gauge. The gauge contains cesium-137 and americium-241 sources (each source has an activity in the millicurie range). The gauge sustained substantial damage with debris scattered c"ar several hundred feet. Additionally, the source rod containing the cesium-137 source had
< .sen broken into three pieces. The truck continued on for approximately 8 miles west, retumed to the incident site, drove approximately 3 miles east and was subsequently stopped.
The area of interest had been cordoned off and the state of Wyoming halted traffic in both directions until a survey of the area was complete.
Personnel from the Wyoming Radiation Control Program and the Wyoming Highway Patrol I were dispatched to the site to conduct a survey of the area to locate the sources. The licensee's radiation safety officer (RSO) was also onsite at the time of the incident. The americium-241 source was found to be intact in the gauge base plate and the cesium-137 source was found detached from the source rod, but intact, approximately 200 feet from the incident site. Initial dose rate measurements for the gauge base plate were as expected, and area surveys of the location where the cesium-137 source was located indicate no contamination on the paving. The licensee's RSO was operating the gauge at the time of the incident, and he reported that he was the only individual in the area at the time the incident occurred. Access to the area was quickly restricted, and no member of the public is expected
-to have received exposure to radiation as a result of the incident. The sources have been
' secured in a shielded container and arrangements are being made to ship the sources back l to the manufacturer for disposal. l Region IV has coordinated with the state of Wyoming and the licensee, and the licensee plans j to submit a written report of the incident. l
)
NMSS and the regional EDO coordinator have been notified. This information has been discussed with the Wyoming Radiation Control and the licensee and is current as of 10:00 a.m. (CDT), October 21,1999. , L-
Contact:
Linda Howell Jeffrey Cruz Ib
'a17\aan no1' t
g' l (817)860-8164 9910250121 991021 PDR IEE PNO-IV-99-045 PDR