When the State Highway Commission determines that the topography of the land adjoining the highways will not permit adequate screening of junkyards, or the screening of such junkyards would not be economically feasible, the State Highway Commission shall have the authority to acquire by gift, purchase, exchange, or condemnation such interests in lands as may be necessary to secure the removal or disposal of the junkyards, and to pay just compensation for the costs of relocation, removal or disposal thereof. When the state highway commission determines that it is in the best interest of the state, it may acquire such lands, or interest in lands, outside highway rights-of-way as may be necessary to provide adequate screening of such junkyards.