[Certification of amounts to be assessed.]

On or before September 1st of each year the board of directors of any such district shall certify to the board of county commissioners of the county in which the office of such district is located, the aggregate amount of money required for the purposes aforesaid; the amount required for the payment of interest upon bonds which may be issued for deposit with the United States and to meet payments required to be made under any contract with the United States, and the amount required for all other purposes under this act [73-8-1 to 73-8-60 NMSA 1978], shall be separately set forth; and the aforesaid certificate shall specify the assessments which are to become due for such purposes upon each tract of land within the district subject thereto. Provided, such lands as during any given year, shall not be subject to charges under the contract with the United States, shall not be assessed during any such year for the purposes of repayment to the United States under any such contract. And provided further, district lands shall be exempted from taxation, for the purposes of repayment to the United States, in any year when, and to the extent that, on account of seepage or other conditions, the district shall be exempted from repayment to the United States for such lands under any such contract as aforesaid.