Gunnar

The Gunnar site is located on the shore of Lake Athabasca approximately 25 kilometres south of Uranium City.

During operation, the Gunnar Mine Site consisted of:

The Gunnar Pit is 304 metres long, 244 metres wide and 116 metres deep. It is located very close to the shores of Lake Athabasca. The rim of the pit is separated from Lake Athabasca by a narrow bedrock ridge.

Access to the underground mining was via a shaft sunk 600 metres (1900 feet) deep. The headframe is still largely intact.

While in operation, annual production ranged from 700,000 to 785,000 tonnes between 1958-1963. The highest ore grade was 0.19% U₃O₈ obtained in 1956.

Tailings were deposited in three areas: Gunnar Main, Gunnar Central and Langley Bay. Approximately 4.4 million tonnes of tailings were deposited during operation of the mine/mill. Tailings were first deposited into a depression 500 m north of the mill. This area is called Gunnar Main tailings and is approx 14 m deep. Once that area was full, tailings were directed to small depression called Gunnar Central tailings — to the east of the main site. From there, tailing flowed further downhill into Langley Bay, splitting Langley Bay into what is now known as Langley Bay and Back Bay.

In addition there is an estimated 2.7 million cubic meters of waste rock on the site. It is located in two piles near the flooded pit.

The mine operated for nine years and was officially closed in 1964 with little to no decommissioning. That same year, the pit was filled by blasting a narrow trench in the rock to Lake Athabasca. Water flowed directly from the lake into the open pit eventually flooding the underground workings as well. In 1966, the channel was blocked by filling it with waste rock.

The proposed project involves the: demolition of existing buildings, facilities and structures; appropriate disposal of materials resulting from demolition; installation of an appropriate cover on all or a portion of the exposed mill tailings; rehabilitation of existing waste rock piles; rehabilitation of additional risk(s), as warranted; general site clean-up and re-vegetation, as required; and appropriate monitoring during and after rehabilitation.

Additional information is available for free download as PDF documents below: