(e) The full and true value of taxable property used or committed by contract or other agreement for pipeline transportation of gas or unrefined oil or in the operation or maintenance of facilities for the pipeline transportation of gas or unrefined oil is:
- (1) on the construction commencement date and until January 1 following the date the pipeline begins to transport gas or unrefined oil, the actual cost incurred or accrued with respect to the property as of the date of assessment;
- (2) determined on each January 1 thereafter with due regard to the economic value of the property based on the estimated life of the proven reserves of gas or unrefined oil then technically, economically, and legally deliverable into the transportation facility; however, if the proven reserves of gas or unrefined oil then technically, economically, and legally deliverable indicate an economic life materially shorter than the estimated physical life of the transportation facility, the full and true value is the actual cost reduced by an annual allowance for depreciation on a straight line basis over an economic life based on the actual elapsed life from the commencement of full operation to the date of assessment plus the estimated remaining life of the proven reserves of gas and unrefined oil then technically, economically, and legally deliverable into the transportation facility as of the date of the assessment;
- (3) on the assessment date next following inability to use or construct all or a substantial part of the facility for a period of 90 or more consecutive days because of natural disaster or legal prohibition, or other events beyond the control of a person having ownership or control of the property, adjusted to take into account any diminution in value.