1. Thеre was in the record considerable evidence introduced in an effort to show that the use of natural gas
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as a chemical used, in the manufacture of fertilizer and other products serving the food industry was in its own way as important to the health of consumers generally аs its use in the conventional line of supplying heating and energy requirements. There was also considerable evidence indicating that while the rates at issue here would in the first instance apply only to CNC and Nipro, there were other industrial consumers extant and still others on thе horizon who might be eligible for whatever rate schedule was set, and that such rate schedule should therefore be so tailored as to be available to others in substantially the same category. This, however, still pinpoints the rates at issue narrowly within only a part of onе of the nine categories to which the rates are applied. As is pointed out in
Ga. Power Co. v. Ga. Public Serv. Comm.,
2. There was filed with the Public Service Commission’s order in this case and forwarded with the record to the superior court the affidavit of James Crudup, director of utilities engineering of the commission, and three exhibits attached thereto, representing the current rate schedules N-9 (industrial interruptible service) and N-15 (preferred interruptible service) (being two other categories of the nine referred to above) and certain arithmetical calculations designed to show the effect in dollars of proposed rate adjustments, all for the year 1976, showing revenues of CNC and Nipro as of the test year (Docket 2943-U), of the last docketed general rate proceeding. These latter included CNC and Nipro rates effective October 18, 1974, and September 30, 1977, *372 respectively (matters necessarily known to the appellant and to these two corporations) plus the statement of new requirements agreed upon between the parties, plus the multiрlication of the number of therms of supplemental supplies by the price per therm. This, by the process of addition of new and supplemental requirements at the stated therm price, yielded the total new revenue in dollars. No new facts were thereby added to thе record.
Code § 3A-114 (a) (8) (G) of the Administrative Procedure Act provides that in all contested cases the record shall include all staff memoranda or data submitted to the hearing officer or members of the agency in connection with their consideration of the case. Code § 3A-116 (d) provides: "Official notice may be taken of judicially recognizable facts. In addition, official notice may be taken of technical or scientific facts within the agency’s specialized knowledge. Parties shall be notified either before or during the hеaring, by reference in preliminary reports or otherwise, of the material noticed, including any staff memoranda or data, and they shall be afforded an opportunity to contest the material so noticed. The agency’s experience, technical cоmpetence, and specialized knowledge may be utilized in the evaluation of the evidence.”
It is strongly urged that failure to introduce this staff memorandum in evidence or to give notice to the public utility and an opportunity to be heard on its contents is in defiance of these requirements of the Act and constitutes reversible error. We agree with the appellant that it would be in all cases advisable to give notice of any staff memoranda which are intended to be sent up with the record in the case. We do not agree that fаilure to do so in this case will necessitate a reversal. The N-9 and N-15 schedules were schedules under which Atlanta Gas Light operated and with which it was necessarily as familiar as with any other part of the rate proceedings. The arithmetical balance sheet was no more than a reduction to figures of formulae gone into in detail during the hearings. The appellant does not contend that there are any errors of fact contained therein, or any factual material unknown to it, but does contend that it could have introduced оther evidence by cross examination and *373 rebuttal had it known of these memoranda in time. In view of the thrust of the arguments of Atlanta Gas Light for a higher rate, we find nothing in its position which could reasonably be said to have been omitted by reason of not having seen this particular stаff memorandum at an earlier time. The memorandum itself is in broad overview a calculation to be used, following known facts, in arriving at a particular arithmetic conclusion.
The construction of statutory language resembling Code § 3A-116 (d) has been considered by other states аnd failure to adhere strictly to its demands has been held not to raise a conclusive presumption of harmful error. Referring to the use of official notice by the Interstate Commerce Commission, it was held in United States v. Pierce Auto Freight Lines,
3. It is further contended that the rate order is arbitrary, capricious, confiscatory, built on a concept foreign to the accepted theory of ratemaking, and totally without supporting evidence. We are aware of, and respect the principals enunсiated in, the many cases cited
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by the appellant to the effect that this court must closely scrutinize the evidence "for without an appropriate understanding of the case the court cannot properly perform its appellate function,” rather thаn hiding behind an "any evidence” decision. Ethyl Corp. v. E. P. A., 541 F2d 1, 36 (DC Cir. 1976). Nevertheless, where there is competent expert testimony on both sides relating to highly technical results of future actions, appellate courts can and should respect the expertise of the tribunal involved, the burdеn remaining upon the losing party to demonstrate harmful error. We have held that in determining the rate of the exti;a requirements of the consumers involved here it was proper to use the figures, so far as applicable, applied overall as established in the last general rate case. So applied, .evidence which supports a decision that the result reached is fair and reasonable, that is, that it bears its proportionate part of the cost of the service plus an amount sufficient to reasonably compensate its investors and maintain its credit, is in accord with substantive due process, but this rule means that "the total revenue requirement of a regulated utility is the sum total of its proper operating expenses, depreciation expense, taxes, and a reasonablе return on the net valuation of its property,” but does not require that each individual rate must be fixed by a recomputation from month to month or from day to day of the entire structure as a ratio of which the individual rates are fixed. Cf.
Ga. Power Co. v. Ga. Public Serv. Comm.,
Ratemaking generally is a legislаtive function which the legislature has delegated to the Public Service Commission.
Sou. Bell Tel. & Tel. Co. v. Ga. Public Serv. Comm.,
Judgment of the Superior Court of Fulton County affirming the order of the Georgia Public Service Commission is affirmed.