(a) As used in this Code section, the term:

(1) "Adjustment factor" means a factor used pursuant to a purchased gas adjustment rate to recover purchased gas costs.

(2) "Commission" means the Georgia Public Service Commission.

(3) "Firm customer" means a customer who purchases gas from a gas utility on a firm basis which ordinarily is not subject to interruption or curtailment.

(4) "Gas supply plan" means the particular array of available gas supply, storage, and transportation options selected by a gas utility to supply the requirements of its firm customers.

(5) "Gas utility" means a gas utility subject to the jurisdiction of the commission.

(6) "Purchased gas adjustment rate" means a purchased gas adjustment rider or similar rate, provision, or clause in the tariff of a gas utility pursuant to which purchased gas costs are billed to the firm customers of the gas utility.

(7) "Purchased gas costs" means all costs incurred by a gas utility for the purpose of acquiring gas delivered to its system in order to supply its firm customers, including without limitation the costs incurred in purchasing gas from sellers; the costs incurred in transactions involving rights to buy and sell gas; the costs incurred in gathering gas for transportation to the gas utility; the costs incurred in transporting gas to the facilities of the gas utility; the costs incurred in acquiring and using gas storage service from others, including the costs of injecting and withdrawing gas from storage; and all charges, fees, and rates incurred in connection with such purchases, rights, gathering, storage, and transportation.

(8) "Recovery year" means the 12 calendar months commencing October 1, 1994, and ending September 30, 1995, and each succeeding 12 calendar month period thereafter.

(b) Commencing October 1, 1994, the requirements of this Code section shall apply to any purchased gas adjustment rate. The requirements of Code Section 46-2-25 shall not apply to filings made or proceedings conducted pursuant to this Code section.

(c) On or before August 1 of each year, each gas utility shall file with the commission its gas supply plan for the following recovery year. The gas utility shall include with such filing the adjustment factors it proposes for recovering its purchased gas costs during such following recovery year, together with the calculations that produced such factors.

(d) Not less than ten days after any such filing by a gas utility, the commission shall conduct a public hearing on such filing. The gas utility's testimony shall be under oath and shall, with any corrections thereto, constitute the gas utility's affirmative case. At any hearing conducted pursuant to this Code section, the burden of proof to show that the proposed gas supply plan and adjustment factors are appropriate shall be upon the gas utility.

(e) Following such a hearing, the commission shall issue an order approving the gas supply plan filed by the gas utility or adopting a gas supply plan for the gas utility that the commission deems appropriate. In addition, the commission in its order shall approve the adjustment factors proposed by the gas utility or adopt adjustment factors that the commission deems appropriate. The adjustment factors approved or adopted by the commission, or otherwise made effective under this Code section, shall be applied uniformly to all firm customers upon the effective date of such factors. The adjustment factors to be effective during the recovery year commencing October 1, 1994, shall be set at levels appropriate to account for underrecoveries or overrecoveries, if any, under the purchased gas adjustment rate of the gas utility in effect prior to October 1, 1994. The adjustment factors to be applicable during each recovery year commencing October 1, 1995, and thereafter, shall be set at levels appropriate to account for underrecoveries or overrecoveries during the preceding recovery year. Should the commission fail or refuse to issue an order by the forty-fifth day after the gas utility's filing which either approves the gas supply plan filed by the gas utility or adopts a different gas supply plan for the gas utility, the gas supply plan proposed by the gas utility shall thereupon be deemed approved by operation of law. Similarly, should the commission fail or refuse to issue an order by such date which either approves the adjustment factors proposed by the gas utility or adopts different adjustment factors for the gas utility, the adjustment factors proposed by the gas utility shall thereupon be deemed approved by operation of law.

(f) The provisions of law relating to parties, intervention, and discovery in proceedings before the commission shall apply with respect to proceedings under this Code section.

(g) Each gas utility shall file with the commission monthly its actual monthly purchased gas costs and accumulated purchased gas costs during the recovery year. The gas utility shall include in such filing information which demonstrates whether such purchased gas costs were incurred in accordance with a gas supply plan which had become effective in accordance with the provisions of this Code section.

(h) Each gas utility shall also file with the commission monthly the most current data available showing the monthly and accumulated overrecoveries or underrecoveries of actual purchased gas costs resulting from application of its purchased gas adjustment rate.

(i) At least every three calendar months, the gas utility shall file proposed revisions to the adjustment factors based on actual unrecovered purchased gas costs in order that the revenues to be recovered pursuant to such rate during the remainder of the current recovery year shall equal, as nearly as possible, the gas utility's unrecovered purchased gas costs through the end of such recovery year. The revisions to the adjustment factors, if any, shall be made to the nearest 0.01¢ per therm. Unless the commission directs otherwise, such revised adjustment factors shall become effective on the first day of the first calendar month that begins at least 15 days after the date of such filing.

(j) All commission orders issued pursuant to this Code section shall contain the commission's findings of fact and conclusions of law upon which the commission's action is based. Any such order shall be deemed a final order subject to judicial review under Chapter 13 of Title 50, the "Georgia Administrative Procedure Act."

(k) The commission shall not prohibit or limit the operation of a purchased gas adjustment rate of a gas utility to the extent that the adjustment permits increases or decreases to adjust for increased or decreased purchased gas costs when such increased or decreased purchased gas costs shall have become effective under the procedures of a federal regulatory agency or under a contract approved by a federal regulatory agency. Any subsequent refunds received by a gas utility with respect to any such increased purchased gas costs which become effective under procedures of a federal regulatory agency, or otherwise, shall be treated by the gas utility in such manner as the commission may direct.

(l) Any purchased gas costs which are incurred by a gas utility in accordance with a gas supply plan which was in effect pursuant to the provisions of this Code section at the time such costs were incurred may be recovered by the gas utility under its purchased gas adjustment rate and shall not be disallowed retroactively by the commission nor by any court which reviews the action of the commission in the absence of fraud or willful misconduct on the part of the gas utility; provided, however, that the commission may disallow and make appropriate adjustments for any purchased gas costs that were not incurred in accordance with such a gas supply plan if the same resulted in higher purchased gas costs and were the result of clearly imprudent conduct on the part of the gas utility. The provisions of this Code section shall not prohibit the commission from authorizing a gas utility to recover under a purchased gas adjustment rate costs or amounts in addition to purchased gas costs, nor shall the provisions of this Code section prohibit the commission from removing from purchased gas costs those costs incurred by a gas utility for the purpose of acquiring gas to supply customers who are not firm customers.

(m) After a gas supply plan has become effective under the provisions of this Code section as a result of a proceeding before the commission, the commission shall retain jurisdiction of the proceeding for the balance of the recovery year for the purposes set forth in this subsection. Upon the application of the affected gas utility or upon its own initiative, the commission may, after affording due notice and opportunity for hearing to the affected gas utility and the intervenors in the proceeding, amend the gas supply plan of the affected gas utility for the remainder of the recovery year. The amended gas supply plan shall become effective upon the date of the commission's order and shall not have retroactive effect.