EnviroCopper can earn up to 75% of the rights over metals produced by in-situ recovery at Kapunda.
Thor holds a 25% interest in EnviroCopper an option to increase its stake to 30%.
The testwork program is funded by a government grant of A$2.85mln.
A series of holes will test the hydraulic properties of the host rock, including flow rates, effective porosity & permeability, hydraulic connectivity, and also the storage coefficient;
The drill samples will be assayed for copper, gold along with other elements with the mineralised samples also to be used for further column leach test work.
Mick Billing, executive chairman, said: "This program is a key milestone in further demonstrating the technical viability of the Insitu Recovery (ISR) process at Kapunda.
"The Thor investment in EnviroCopper Limited is becoming one of increasing importance as the resource base at both Kapunda and Moonta grows, technical hurdles are addressed, and prospects for commercial viability continue to develop."
In early morning trading, shares in Thor Mining were 4.2% higher at 0.25p.
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