(a) In addition to any other requirements of the Act, these regulations, and the apportionment resolution, a district shall contribute the following funds as soon as they become available to the district toward the cost of the project or, if the project be completed, toward the reduction of any apportionments previously made; the contributions to be proportionate to the District's and State's participation in the project.

1. (1) The net proceeds from the sale, or the fair value as determined by the Director of General Services, whichever is greater, or the net revenue derived from the lease or rental of the following:

   1. (A) Facilities required by the Board to be disposed of.
   2. (B) Improvements, materials, crops and natural resources on a site or sites purchased under an application.
2. (2) Interest earned on any funds available for cost of a project including interest reasonably attributable to such funds where the same are commingled with other funds earning interest.

(b) The Director of General Services shall determine, on behalf of the Board, the amount of funds a district is required to contribute under subsections

1. (1) and (2) above. Such determination shall be binding upon the district; however, after receipt of written notice of such determination, the district may file an appeal with the Board within six months thereafter, in which event the decision of the Board may affirm or modify the determination of the Director of General Services.