Section 20.03.05.031 - SIZE AND COMPOSITION OF LEASABLE TRACT01.One Mile Limitation. A riverbed lease may not exceed one (1) contiguous river mile in length or all the riverbed within one (1) section should all the available state lands within the section exceed one (1) river mile. (3-18-22)02.Construction Materials. Leases for construction materials may be limited to a smaller size tract at the Board's discretion. (3-18-22)Idaho Admin. Code r. 20.03.05.031