PUC §21687: (a) (1) If an airport, for which payments have been made from the Aeronautics Account, ceases to be open to the general public for more than one year, the public entity to which those payments were ma

(a) (1) If an airport, for which payments have been made from the Aeronautics Account, ceases to be open to the general public for more than one year, the public entity to which those payments were made shall pay to the state funds equal to the amount computed by the department pursuant to paragraph (2), and those funds shall be deposited in the Aeronautics Account. (2) (A) The department shall compute an amount equal to the total of all payments made for the airport from the Aeronautics Account during the preceding 20 years, less 5 percent of the amount of a particular payment multiplied by the number of years since the payment was made, or the unused balance, whichever is greater. (B) The computation described in subparagraph (A) shall not include any payment the department made pursuant to Section 21682, if, upon the request of the public entity that owns and operates the airport, the department determines that the airport is not necessary to the system of public airports in this state. When making this determination, the department shall consider all of the following factors: (i) Whether the airport is approved for night operations. (ii) Whether the airport has an approved instrument approach procedure. (iii) How many aircraft are based at the airport. (iv) Whether the airport is used for airborne fire attacks. (v) Whether the airport is used for emergency medical transportation. (vi) What services the airport provides for the community. (vii) The size of the community that is served by the airport. (viii) Whether any aviation or transportation planning agency has designated the airport as having a significant role. (ix) Whether a suitable, public-use airport is situated within a reasonable distance. (x) Whether closure of the airport will have a negative effect on other airports. (xi) Whether the airport is used for law enforcement purposes. (b) This section does not apply to either of the following: (1) An airport that is replaced by a comparable facility, as determined by the department, within a period of one year. (2) An airport for which the department, on or after January 1, 1981, has suspended the airport permit and for which payments made pursuant to this article are being expended to correct the deficiency or condition that resulted in the suspension of the airport’s permit.