then, upon giving notice by mail to the owners if known, or if not known, by posting notice upon the property and advertising once in a newspaper of general circulation in the county in which the property lies, the state shall have the right to enter upon the property adversely affected by past coal mining practices, and any other property which is necessary for access to such property, to do all things necessary or expedient to restore, reclaim, abate, control, or prevent the adverse effects. Such entry shall be construed as an exercise of the police power for the protection of public health, safety, and general welfare and shall not be construed as an act of condemnation of property nor of trespass thereon. The moneys expended for such work and the benefits accruing to any such property so entered upon shall be chargeable against such property, and shall mitigate or offset any claim or action brought by any owner of any interest in such property for any alleged damages by virtue of such entry; provided, however, that this provision is not intended to create new rights of action or eliminate existing immunities.