20 ILCS 1920/2.05

(a) The Department or such agency or department of State government as the Department may designate pursuant to subsection (d) of Section 3.05 shall have the right to enter upon any property for the purpose of conducting studies or exploratory work to determine the existence of adverse effects of past coal mining practices and to determine the feasibility of restoration, reclamation, abatement, control, or prevention of such adverse effects. (b) Entry under this Section shall be construed as an exercise of the police power for the protection of public health and safety and shall not be construed as an Act of condemnation of property nor trespass thereon.