70 ILCS 805/6f
A forest preserve district that acquires a parcel of land in excess of 600 acres that includes one or more vacant, subdivided residential outlots on the boundary of the 600 acres, regardless of whether the outlots are contiguous to one another, may sell the outlots when the board of commissioners determines that the sale is advantageous to the district. The board shall approve the sale by an affirmative vote of two-thirds of the members of the board then holding office. A sale may not be approved by the board unless all the parcels involved in the sale have been appraised by an MIA appraiser or a State-certified real estate appraiser within one year before the date the sale is to take effect. Any property sold under this Section must be sold for fair market value. The net proceeds of the sale of any parcel of land under this Section shall be set aside and expended only for capital improvements that are required to make the 600 acres accessible and open to the public or the payment of bond indebtedness associated with the purchase of the 600 acres.
70 ILCS 805/6f