(1) The board of directors may require, as a condition to the granting of an annexation petition, that the petitioners shall severally pay to the district such respective sums, as nearly as the same can be estimated, as said petitioners, or their grantors, would have been required to pay such district, had such lands been included in such district at the time it was originally formed, together with a proportionate share of the expenses of the district accrued since formation.
(2)  If the petition of a nonirrigator seeks only to participate in the district’s mitigation plans and other mitigation activities, the board may require a proportionate sum of the mitigation expenses accrued since the district was originally formed to be paid as a condition to the granting of an annexation petition.