Supervising Scientist Division

Supervising Scientist Annual Report 2003 - 2004: Nabarlek

Supervising Scientist, Darwin, 2004
ISBN 0 642 24391 3
ISSN 0 158-4030

2 - Environmental assessments of uranium mines (continued)

2.4 Nabarlek

2.4.1 Developments

Discussions between Pioneer International Ltd (on behalf of Queensland Mines Pty Ltd) and the Northern Land Council (on behalf of the Traditional Owners) on issues related to the rehabilitation expectations for Nabarlek continued during 2003-04. This includes arrangements to complete site clean-up, particularly the former camp area and laboratories.

During the 2003-04 period, Nabarlek Minesite Technical Committee (MTC) members started the process of developing a final closeout plan for Nabarlek. The September 2003 meeting of the MTC collectively identified the rehabilitation issues that need to be addressed prior to Pioneer being allowed to relinquish its lease on the area. Following this meeting, the oss coordinated production of a status report on Nabarlek rehabilitation issues. This document still remains under discussion with MTC members and is expected to be finalised in the next reporting period. When complete, this document should help MTC members identify and agree on final closeout criteria for the Nabarlek site.

Nabarlek Rehabilitation Bond

During its September 2003 meeting, the Alligator Rivers Region Technical Committee was advised that the rehabilitation bond for Nabarlek had been reduced from $10 000 000 to $400 000. The Supervising Scientist subsequently raised concerns regarding the process for changing the rehabilitation bond.

At the December 2003 meeting of the Nabarlek MTC, DBIRD advised that the bond was revised subsequent to the submission of the last Mine Management Plan (MMP). It was agreed that the bond would be reassessed on the submission of the next MMP with the consultation of the MTC members.

Pioneer submitted a draft MMP for comment in May 2004. Comments on the draft MMP have been provided and the plan is being finalised prior to approval by DBIRD.

Minesite Technical Committee

The Nabarlek Minesite Technical Committee met three times during the year. Table 2.13 provides information on the meeting and the major points of discussion.

Table 2.13: Nabarlek Minesite Technical Committee meetings
Date Significant agenda items
9 September 2003 Mine Management Plan and application for Authorisation, radon and gamma levels, mine rehabilitation, mine closure timetable and future of Nabarlek site and surrounds.
8 December 2003 Radiologically anomalous area, update on rehabilitation and management activities, rehabilitation, status, rehabilitation bond and environmental monitoring.
17 March 2004 Radiologically anomalous area, update on rehabilitation and management activities, rehabilitation status issues and environmental monitoring.
Authorisations and Approvals

Changes to, and approvals under, the Authorisation during 2003-04 are listed in Table 2.14.

Table 2.14: Nabarlek Authorisation changes/approvals
Date Issue
22 September 2003 Variation 0137-01 replacing the schedule with a new Mining Management Act compatible Authorisation.
Incidents

There were no reportable incidents at Nabarlek during the year.

2.4.2 On-site environmental management

Routine monitoring of the site continues to be undertaken by staff of DBIRD. The results published to date indicate that there are no detectable impacts arising from the site in the surface waters and that the ground water impacts remain insignificant. In the former forest irrigation area the ground water quality continues to approach the pre-mining condition. Pioneer's annual report includes photographic records of the site to demonstrate the development of the vegetative cover across the site. eriss staff continue to conduct research programmes at Nabarlek. SSD staff make at least two formal visits to the site during the year.

Radiologically Anomolous Area

The Radiological Anomalous Area (RAA) previously referred to as the 'Badlands' continues to be investigated by members of the MTC and was a standing agenda item for MTC meetings during the year. The RAA is approximately 0.4 ha and is located southwest of the historical pit area. The area has historically shown elevated levels of radioactivity. There is no vegetation, although a few plants are slowly encroaching on the area.

A sequence of aerial photographs presented by eriss at the December 2003 MTC meeting indicated the area covered by the present RAA may have been a site where material from the pit was stockpiled prior to rehabilitation. It is thought that this material was subsequently removed to the pit during rehabilitation and the RAA may be the result of shallow residual contamination due to seepage from the past stockpile.

At the March 2004 MTC meeting, members agreed to a plan of works to delineate and define the presence and extent of contamination. oss, with the aid of DBIRD staff and the cooperation of Pioneer, plans to undertake an auger programme to assess the soil profile of the area. This will be combined with a ground radiation survey of the broader area. These works will probably be undertaken in September or October 2004. It is hoped the resulting information will enable the MTC to provide Pioneer with a remedial solution for the RAA.

2.4.3 Off-site environmental protection

Routine monitoring of the site continues to be undertaken by staff of DBIRD. Results to date indicate no detectable impacts arising from the site in the surface waters and that ground water impacts remain insignificant. In the former forest irrigation area the groundwater quality continues to approach the pre-mining condition.