South Alligator Valley abandoned uranium mines - hazard reduction program: Triennial radiation survey - October 2002

2003

Internal Report 408
Waggitt P
Supervising Scientist Division
Department of the Environment, Water, Heritage and the Arts

About the report

As part of the ongoing program of monitoring of previous hazard reduction works and rehabilitation for the abandoned uranium mines in the South Alligator Valley a radiation survey was conducted by Peter Waggitt (oss) with the assistance of Lassmyn Shiosaki from the SSD Jabiru Field Station. The triennial survey was carried out from 28 to 30 October 2002 and adopted the methodology used previously. The previous survey was completed in August 1999.

All containment sites were found to be performing satisfactorily from an erosion aspect. Although some of the individual radiation readings were higher than background, the limited occupancy of the sites meant that no site was deemed to be giving rise to a dose in excess of 1mSv per year. This resulted in the decision that no further intervention was required at this time. Revegetation at the sites was variable but generally satisfactory.

In the course of the survey the opportunity was taken to inspect the state of the remedial works at the Gunlom Road tailings site and the waste storage facility. All was found to be satisfactory. The annual inspection regime will resume, as usual, in the dry season and a full radiation survey will be undertaken in 2005. However, a further check survey will be made at the bund and weighbridge sites in 2003 as a check on the results of the present survey and to establish that there has been no deterioration of the sites.