The cost of a producer in maintaining an approved underground saltwater disposal system for the purposes of this subchapter shall include the following:
(1) An allowance, to be spread equally over each severance tax reporting period, for depreciation of the actual cash investment of the producer in the constructing, equipping, and improving of an approved underground saltwater disposal system, which depreciation period shall not be less than five (5) years nor more than ten (10) years as may be approved by the Secretary of the Department of Finance and Administration;
(2) The actual cash outlay of the producer in purchasing stock in a business or corporation organized exclusively for the purpose of constructing and operating an approved underground saltwater disposal system; and
(3) The actual expenses of the producer in operating and maintaining an approved underground saltwater disposal system.
(4) These expenses shall include the cost of labor, supplies, materials, utilities, and other necessary operating expenses.
(5) For a producer who purchases the services of an approved underground saltwater disposal business or corporation for disposing of salt water produced in the production of oil or natural gas by the producer, the actual cost of the service is deemed to be the cost of the producer within the meaning of this section.