605 ILCS 5/9-115
It is unlawful for any person to excavate or remove or cause the excavation or removal of the lateral support within a distance of 10 feet plus one and one-half times the depth of any excavation adjacent to the established right-of-way of any public highway located outside the corporate limits of any municipality, except that if any of the excavated materials be of solid rock, the depth of such solid rock shall not be considered in computing the limit of excavation from such right-of-way line of such public highway.
It is unlawful for any person to deposit spoil or cause the spoil from any excavation to be deposited in such a manner that the toe of such spoil will be nearer than 20 feet to any established right-of-way of any public highway located outside the corporate limits of any municipality.
Whenever any person violates or causes the foregoing provisions of this Section to be violated, he shall be guilty of a petty offense for each day such violation occurs and until such unlawful excavation is backfilled or unlawful spoil banks are removed, either by the offenders or by the public authorities as provided hereinafter in this Section.
Where any such violation occurs along any public highway the proper highway authority having jurisdiction of that particular highway is authorized to take the necessary steps as required by law to enter upon the property where such violation occurs and backfill or cause to be backfilled the unlawful excavation or remove or cause to be removed the unlawful spoil banks, whichever case it may be, or both, in such a manner as will conform with the foregoing provisions of this Section, and the costs of such work, together with court costs, may be recovered from such violators in the circuit court in the county where such violation occurred.
Nothing in this Section shall prohibit the construction and maintenance of grade separation crossings of any public utility, private corporation or individuals, or in any way conflict with any other laws governing such grade separations; nor shall the provisions of this Section in any way apply to pipe line construction or maintenance where such work is done to the satisfaction of the highway authorities having jurisdiction over such public highway; nor to the excavation of earth necessary for the construction of foundations or basement walls.
605 ILCS 5/9-115