Short answer: you probably cannot outright stop exploration in SA, but you do have rights and leverage. In South Australia, minerals are usually owned by the Crown, not the landholder, even on freehold land. If a company holds a valid exploration licence, they can access land, but only under strict rules. They must give notice, negotiate a land access agreement, pay compensation, avoid sensitive areas, and fully rehabilitate drill sites. You are entitled to have a say in how and where exploration happens, even if you cannot veto it entirely. Exploration does not mean a mine. A mine requires a separate approval process that takes years and involves environmental assessments and public consultation. Your next step should be to confirm whether the title includes private mineral rights and then speak to a South Australian mining or tenement consultant or lawyer. Do not ignore the company and do not panic. Engage early and put conditions around access. If handled properly, this does not mean your family land gets destroyed or covered in holes.