On Motions for Clarification and/or Stay and on Petitions for Rehearing
ORDER
PER CURIAM.Upon consideration of the motion of petitioners in Appeal No. 74-2123 for stay in the second interim curtailment plan, the responses thereto, said petitioners’ reply, and the answer of petitioner, Southern California Gas Company to the reply, it is
ORDERED, by the Court that the motion for stay is denied for the reasons set forth in the opinion for the court filed this date.
ORDER
Upon consideration of the motion of Intervenor, Salt River Project Agricultural Improvement and Power District for clarification of this court’s opinion, it is
ORDERED, by the Court, that the motion is denied for the reasons set forth in the opinion for the court filed this date.
ORDER
Upon consideration of the petitions for rehearing filed by Petitioners in Appeal No. 74-2123 and by Intervenors, El Paso Natural Gas Co., and Pacific Gas and Electric Co., it is
ORDERED by the Court that the aforesaid petitions are denied.
Opinion for the Court filed by Circuit Judge MacKINNON.
MacKINNON, Circuit Judge:On June 30, 1977, this court decided City of Willcox, et al. v. Federal Power Commission, No. 74-2123 et al. In that case, we reviewed an interim curtailment plan for deliveries of natural gas on the El Paso Natural Gas System. This plan, which was formulated in Federal Power Commission Opinion Nos. 697 and 697A, was found deficient in five respects. We remanded the case to the Commission with instructions to implement our holdings regarding those deficiencies. 185 U.S.App.D.C. at 315, 567 F.2d at 422.
On June 1, 1977, the Commission issued Order Denying Rehearing and Accepting Tariff Sheets, which had the effect of directing the implementation on July 1, 1977 of the interim curtailment plan which was the subject of our June 30, 1977 opinion. On July 14, 1977, the City of Willcox (Will-cox) and Arizona Electric Power Cooperative, Inc. (AEPCO) petitioned this court to stay the FPC’s June 1, 1977 order.
*319On July 12,1977, Salt River Project Agricultural Improvement and Power District (Salt River) presented a motion for clarification of our June 30, 1977 opinion. Several other parties have also each petitioned for rehearing on certain aspects of our opinion.1
We take judicial notice of the FPC’s Order Denying Motion for Stay, Granting Rehearing, Modifying Curtailment Plan, Establishing Further Hearings, Consolidating Hearings, and Requiring Action to Obtain Remand of Record, issued July 29, 1977. The Commission ordered the interim curtailment plan developed in Opinion Nos. 697 and 697A 2 to remain in effect, subject to certain modifications we ordered in City of Willcox. Specifically, the Commission directed that fuel devoted to ignition and flame stabilization remain in Priority 2 status3 (see 185 U.S.App.D.C. at 297-298, 315, at 404-405, 422 of 567 F.2d); that electricity-generating turbine fuel be placed in Priority 3 rather than Priorities 4 and 5 (see 185 U.S.App.D.C. at 298-301, 315, 567 F.2d at 405-08, 422); and that attachments of new residential and commercial users up to December 19, 1974 be included in base period requirements (see 185 U.S.App.D.C. at 301-303, 304, 567 F. 2d at 408-410, 411). The Commission also directed that hearings be held to provide a record for determining (1) whether electricity-generating turbine fuel should be reclassified from Priority 3; (2) whether Arizona Public Service Co. and Tucson Gas and Electric Co. were dilatory in obtaining state permission to reject new customers after December, 1974, and whether an additional base period adjustment should be permitted these customers for attachments occurring between December 19, 1974 and the date of state imposition of a new attachment moratorium (see 185 U.S.App.D.C. at 302, 304, 567 F.2d at 409, 411); (3) how to take into account pre-existing shortages of natural gas in California during the base period when determining California’s volumetric entitlement (see 185 U.S.App.D.C. at 301-305, 315, 567 F.2d at 408-412, 422); and (4) how to allocate storage injection volumes in accordance with the requirements we elucidated in City of Willcox (see 185 U.S. App.D.C. at 305-307, 315, 567 F.2d at 412-414, 422). In short, as a result of the Commission’s July 29, 1977 order, all of the modifications of the interim curtailment plan that we ordered in City of Willcox have either been implemented or will be the subject of hearings to determine how they should be implemented.
We now turn to the various motions and petitions. Salt River, AEPCO, and Willcox, in their motions for clarification and/or stay, urge that electricity-generating turbine fuel be reclassified to Priority 3 from Priorities 4 and 5. Because the Commission has already implemented this reclassification, the motions of these parties for this modification are moot and are therefore denied.
As an independent ground for a stay of the interim curtailment plan, Will-cox and AEPCO assert a great interest in lowering the California users’ storage priority, pending the Commission’s compliance with our mandate to establish a storage priority scheme whereby “the priority accorded to natural gas kept in storage be in proportion to the eventual end uses of that gas . . . .” 185 U.S.App.D.C. at 307, 567 F.2d at 414. The FPC’s July 29, 1977 order directs that hearings be held on *320this specific matter. It has scarcely been two months since our decision in City of Willeox; accordingly, we believe it would be premature to interrupt the Commission’s deliverations at this time. The Commission has recognized that it cannot implement the plan described in Opinion Nos. 697 and 697A on a permanent basis without modification. This is evidenced by the fact that the Commission has altered the plan in certain respects already and is taking steps to gather information with which other modifications can be made. Under the power conferred on the Commission “to prescribe . such orders, rules, and regulations as it may find necessary or appropriate to carry out the provisions” of the act,4 it is open to the Commission to order appropriate interim priorities pending further hearings. The Commission here is dealing with a tariff; in such matters, the statute vests the Commission with the discretion to allow the tariff to become effective immediately or to suspend. The discretion conferred recognizes the acquired knowledge and experience of the agency in matters committed to its regulation and is a sufficient basis for recognizing its authority to prescribe interim priorities during the short period preceding hearings on storage volumes and the other matters awaiting implementation.
It should also be realized that none of the present petitioners alleges that a curtailment of natural gas is currently in effect. Lower priorities which certain users might enjoy until the Commission completes hearings and orders further modification will have no deleterious impact unless curtailment actually occurs.5 Should curtailment occur and El Paso cut off any user entitled by the opinion of this court not to be cut off, that party could either petition the Federal Power Commission to implement our opinion, in keeping with 15 U.S.C. § 717s(a) (1970),6 or following denial of rehearing seek an immediate stay from this court should the Commission not choose to proceed, under 15 U.S.C. § 717r(a) (1970).7 *321In the latter instance, the “order” by which the complainant would be “aggrieved” would be the Commission’s approval of the interim curtailment plan. However, until there is actual curtailment, or at least a more than speculative threat that the Commission will not abide by our opinion in the event of curtailment, no party is presently “aggrieved.”
Granting the motion to lower immediately the California users’ storage priority would constitute precedent for petitioning this court for advisory opinions as to how our decision might apply to various parties. Such decisions are not permitted. No case of immediate harm is presented, and the proper procedure is to afford the Commission the opportunity to implement the decision of this court.
We also take this opportunity to clear up a possible ambiguity, concerning storage gas, that has been pointed out by Pacific Gas & Electric Co., El Paso Natural Gas Co., and Southern California Gas Co. Nothing we have said in our June 30, 1977, opinion should be taken to prevent the Commission, on remand, from finding that storage gas serves high priority uses. The point made in our opinion of June 30, 1977, was simply that, to the extent storage gas is made available to higher priority uses, more non-storage gas will be available to the lower priority uses. We reiterate our holding on storage utilization of natural gas:
In revising its permanent curtailment plan for the El Paso system, the Commission must guarantee: 1) That all use of El Paso-originating natural gas (whether detained in storage for a period of time or not) be recognized in setting the percentage reliance of California customers upon El Paso. 2) That double counting be avoided either by considering the El Paso origin of the natural gas as it is injected into storage, or as it is withdrawn from storage, but not both. 3) That the priority accorded to natural gas kept in storage be in proportion to the eventual end uses of that gas, unless the Commission wishes to support with an evidentiary hearing the importance of storage gas irrespective of the end use to which it is eventually put.
185 U.S.App.D.C. at 307, 567 F.2d at 414. This clarification obviates any need for rehearing.
The motions of Salt River, Willcox, and AEPCO for clarification and/or stay are denied. The motions of Willcox, Pacific Gas & Electric Co., El Paso Natural Gas Co., and Southern California Gas Co. for rehearing are denied.
Order accordingly.
. These parties are Willcox, AEPCO, Pacific Gas and Electric Co., and El Paso Natural Gas Co.
. Opinion Nos. 697 and 697A were clarified in orders issued December 24, 1975, October 15, 1976, and June 1, 1977.
.Fuel devoted to ignition and flame stabilization was placed in Priority 2 status by Order Denying Rehearing, Further Clarifying Opinions, and Requiring Modification of Proposed Tariff Sheets, issued October 15, 1976, Paragraph (E).
. The Commission shall have power to perform any and all acts, and to prescribe, issue, make, amend, and rescind such orders, rules, and regulations as it may find necessary or appropriate to carry out the provisions of this chapter. Among other things, such rules and regulations may define accounting, technical, and trade terms used in this chapter; and may prescribe the form or forms of all statements, declarations, applications, and reports to be filed with the Commission, the information which they shall contain, and the time within which they shall be filed. Unless a different date is specified therein, rules and regulations of the Commission shall be effective thirty days after publication in the manner which the Commission shall prescribe. Orders of the Commission shall be effective on the date and in the manner which the Commission shall prescribe. For the purposes of its rules and regulations, the Commission may classify persons and matters within its jurisdiction and prescribe different requirements for different classes of persons or matters. All rules and regulations of the Commission shall be filed with its secretary and shall be kept open in convenient form for public inspection and examination during reasonable business hours.
15 U.S.C. § 717o (1970).
. Should it be determined by the Commission after hearings that the California users’ storage priority is too high, the Commission can order reallocation in accordance with its new findings.
. (a) Whenever it shall appear to the Commission that any person is engaged or about to engage in any acts or practices which constitute or will constitute a violation of the provisions of this chapter, or of any rule, regulation, or order thereunder, it may in its discretion bring an action in the proper district court of the United States, or the United States courts of any Territory or other place subject to the jurisdiction of the United States, to enjoin such acts or practices and to enforce compliance with this chapter or any rule, regulation, or order thereunder, and upon a proper showing a permanent or temporary injunction or decree or restraining order shall be granted without bond. The Commission may transmit such evidence as may be available concerning such acts or practices or concerning apparent violations of the Federal antitrust laws to the Attorney General, who, in his discretion, may institute the necessary criminal proceedings.
15 U.S.C. § 717s(a) (1970).
. (a) Any person, State, municipality, or State commission aggrieved by an order issued by the Commission in a proceeding under this chapter to which such person, State, munici*321pality, or State commission is a party may apply for a rehearing within thirty days after the issuance of such order. The application for rehearing shall set forth specifically the ground or grounds upon which such application is based. Upon such application the Commission shall have power to grant or deny rehearing or to abrogate or modify its order without further hearing. Unless the Commission acts upon the application for rehearing within thirty days after it is filed, such application may be deemed to have been denied. No proceeding to review any order of the Commission shall be brought by any person unless such person shall have made application to the Commission for a rehearing thereon. Until the record in a proceeding shall have been filed in a court of appeals, as provided in subsection (b) of this section, the Commission may at any time, upon reasonable notice and in such manner as it shall deem proper, modify or set aside, in whole or in part, any finding or order made or issued by it under the provisions of this chapter.
15 U.S.C. § 717r(a) (1970).