The Tupa occurrence is located northeast of Surprise Lake about 42 kilometres northeast of the community of Atlin.

The area is underlain by alaskite of the Late Cretaceous Surprise Lake batholith (Surprise Lake Plutonic Suite) which is overlain by Recent till and glacial debris. A north-south lineament contains strongly radioactive soils. Soil samples assayed up to 0.15 per cent uranium (Assessment Report 6908). This area likely represents the downhill dispersion of uranium in soil.

In 1976, the Tupa claim was staked to cover dry radioactive swamps containing significant contents of uranium. In 1978, Union Oil Company of Canada Ltd. conducted a field program comprising detailed geochemistry and radiometrics over the area of the radioactive swamp in search of polymetallic veins, and reconnaissance geochemistry, radiometrics and geology along the contact of the batholith.