(2) The total amount to be realized from the sale of Carey Act lands and water rights for private lands shall insure the return to the state of all money expended by it in the reclamation of the lands in the project with interest at five percent from the date of the contract of sale, in addition to any further sums or amounts which are found necessary to be paid on account of the project.

(3) Any person who holds a contract with the Columbia Southern Irrigation Company or its successors in interest, for any tract in the project, may execute a new contract with the state for reclamation, under the provisions of ORS 555.310 to 555.410, of the land described in the original contract with the company, or a new selection, receiving credit thereon for the principal paid to the company under the original contract; or, may surrender the contract and receive, in cash, the full amount of principal paid to the company on the contract; provided, however, that no contract holder shall be entitled to a refund of the money as herein provided unless an assignment of all rights, title and interest in and to the contract and the land described therein was filed with the Desert Land Board on or before July 1, 1917; provided, further, that refunds shall be made to contract holders pro rata as funds may become available from time to time after July 1, 1915. The failure to comply with the above option by any contract holder under the old Columbia Southern Project shall render the contract void and the lands embraced therein shall revert to the state and be subject to reentry.