Nabarlek ML

Introduction

Uranium Equities Limited (“UEQ”) purchased 100% of the issued capital in Queensland Mines Pty Ltd, the registered owner of Mineral Lease MLN 962 in the Alligator Rivers Uranium Province, Northern Territory in March 2008. 

 

Mineral Lease MLN 962 contains the historic Nabarlek Uranium Mine, covers an area of 12.79 km2 and was initially granted on the 23 March 1979.

 

The Nabarlek Mine, Australia’s highest grade uranium mine, operated between 1979-1988 and produced a total of 24.4 million pounds of U3O8 at an average grade of 1.84% U3O8 (40.5 lb/tonne U3O8). It lies within the Alligator Rivers Uranium Province.

 

 

The Nabarlek uranium deposit was a structurally controlled ore body hosted by sheared and altered basement metamorphic rocks, lying in the Nabarlek Shear Zone and within a northwest trending structural corridor. This corridor extends across MLN 962 and into the surrounding West Arnhem Joint Venture exploration tenements which are held by Cameco Australia Pty Ltd (60%) and Uranium Equities Limited (40%).

 

 

Queensland Mines Limited discovered surficial uranium mineralisation in the Nabarlek region in June 1970 from the follow-up of an intense airborne radiometric anomaly. 

 

Initial exploration work included trenching, mapping, scintillometer surveys and sampling. Drilling commenced from July-November 1970, then again from April 1971 to December 1971. The initial drilling concentrated on delineating the Nabarlek orebody with minimal exploration work conducted on the area surrounding the orebody within MLN 962.

 

The Nabarlek mine was operated by Queensland Mines Limited from 1978 until 1988; mining was conducted in one campaign of 143 days duration in the dry season and the ore was stockpiled on a custom built impermeable pad. The mill was built through the following wet season and milling commenced in 1980. A total of 606,700t of ore was milled to produce 11,084 t of U3O8 product. During this process 2.3Mt of waste rock material was temporarily stockpiled and 595,900t of tailings material was deposited in the mined out pit.

 

No exploration activities occurred within the mine lease during the period of 1973 to 1981. Exploration work resumed in 1981, with geochemical soil and track etch radon surveys conducted over parts of the ML until 1982. Drilling was initiated from 1983 to 1984 to target 8 anomalous zone identified from the surveys.

Further exploration work resumed in 1994, when percussion with diamond tail drilling was conducted southeast and northwest of the mine. Several water pollution control observation bores were emplaced around the mine and stockpile area for the closure and rehabilitation stage of the mine in 1984.

No further drilling or geological sampling has been carried out on MLN962 since 1994. A number of airborne surveys have been conducted over the ML which have been part of wider regional exploration surveys including radiometrics, magnetics, hyperspectral and electromagnetic (GEOTEM/TEMPEST) surveys.

 

Rehabilitation

Rehabilitation commenced in part in 1988 with the clean up of the mill. In 1992 the pond surfaces were scraped and all residues returned to the pit and the tailings were prepared for consolidation with the insertion of de-watering wicks and the placement of a dry surface cover, geotextile and waste rock. This was left for 6 years to ensure full subsidence. Final dismantling of infrastructure and transport off site occurred in 1994/95 and final revegetation seeding was completed in December 1995. Miscellaneous infrastructure was left for use by the Traditional Owners.

 

The site has not yet achieved regulatory release. Recent issues affecting the rehabilitation success were the devastation caused in 2005 by Cyclone Monica and the recent fire bombing of the site destroying fire intolerant species. 

 

 

Under the Northern Territory Mine Management Act the company has received approval of a revised Mine Management Plan and an authorisation to enable exploration and initial rehabilitation work. A total bank guarantee of $1.8m has been established to cover the legacy rehabilitation obligations. This amount is within UEQ expectations.

 

A special meeting of Traditional Owners on 19th August 2008 approved the proposed exploration work program and gave authorisation to establish a field camp, to commence exploration and to later negotiate an amended exploration agreement.

 

 

The Nabarlek deposit was a small, very high-grade orebody 200m long, 15m thick and 70m deep. The mineralisation is steeply dipping and contained within the Nabarlek Shear Zone.

A review of existing exploration data has identified over 3km of largely untested strike of the Nabarlek Shear Zone within the mine lease.

Areas of exploration potential are shown in Figure 2.

 

 

A priority area (termed the “Pond Prospect”) which extends along the shear north-west of the pit to the lease boundary has had limited exploration drilling. Initial exploration will involve shallow aircore geochemical drilling. Anomalous areas will be targeted with reverse circulation drilling.

The Banksman Prospect, 200m east of the pit, within a sub-parallel structure, has returned 22m @ 675ppm U3O8 from 21m in one hole. The anomaly is open to the north. Reverse circulation drilling is planned to test for extensions of this mineralisation.

Drilling is planned beneath the open pit to test for potential extensions to and repetitions of the Nabarlek ore body both down dip and down plunge.

Exploration is planned to commence in September 2008 with up to two drilling rigs following the establishment of the field camp.