CANBY, Circuit Judge:
The ultimate issue in this case is whether the Hawaii Public Utilities Commission (PUC) violated an order of the Federal Communications Commission mandating use of a particular set of “separations” procedures for allocating the respective costs and investments between interstate and intrastate telephone operations. A threshold question is whether the district court had jurisdiction under § 401(b) of the Communications Act to enforce the FCC order. In essence, the district court’s permanent injunction required the PUC to obey the FCC order by raising Hawaiian Telephone Company’s (HawTel’s) intrastate rates by $10,507,000 annually.
Hawaii’s PUC and Consumer Advocate, as intervenor, appealed. We deferred submission to await the Supreme Court’s recent decision in Louisiana Public Service Commission v. FCC, 476 U.S. 355, 106 S.Ct. 1890, 90 L.Ed.2d 369 (1986), and to permit the parties to comment upon it. We now affirm the district court’s injunction.
BACKGROUND
HawTel provides interstate, intrastate, and overseas telephone service for residents of Hawaii. The FCC sets HawTel’s long-distance rates, and the PUC sets intrastate rates. Because the same physical plant is used for both interstate and intrastate services, some system for apportioning costs and investments is necessary to set fair rates for the respective services. See generally MCI Telecommunications Corp. v. FCC, 750 F.2d 135 (D.C.Cir.1984); McKenna, Preemption Under the Communications Act, 31 Fed.Comm.L.J. 1 (1985). This system of apportionment is referred to as “separations procedures.”
Until recently, interstate rates for telecommunications to and from Hawaii were considerably higher than interstate rates in the 48 contiguous states. In 1972, the FCC determined that Hawaii’s rates should be integrated into the Mainland domestic rate pattern. Interstate rates in Hawaii accordingly were to be adjusted so that they would be roughly comparable to rates in other parts of the United States. In re Establishment of Domestic Communications-Satellite Facilities by Non-Governmental Entities, Second Report & Order (Docket No. 16495), 35 F.C.C.2d 844, 856-57, aff'd on reconsideration, 38 F.C.C.2d 665 (1972), aff'd sub nom. Network Project v. FCC, 511 F.2d 786 (D.C.Cir.1975). The FCC later decided that integration would be accomplished in part by establishing new procedures for interstate and intrastate cost apportionment. The FCC, exercising its authority under 47 U.S.C. § 410, established a special Federal-State Joint Board, to advise it on fair separations procedures for Hawaii. The FCC had not previously prescribed any separations procedures for Hawaii, and the PUC had apportioned costs according to its own “Hawaiian Plan II.”
In 1981, the Joint Board recommended use of the so-called “Ozark Plan,” see 47 C.F.R. §§ 67.1-67.701, for separations. In [1267]*1267re Integration of Rates & Services for the Provision of Communications by Authorized Common Carriers between the United States Mainland & Hawaii & Alaska, Memorandum Opinion & Order (Docket 21263), 87 F.C.C.2d 20, 24 (1981). The Ozark Plan, which was developed through cooperative efforts of the FCC and utility regulators nationwide, had been used in the 48 states for some time. The Joint Board suggested extending the Plan for use in Hawaii without modification. Id. The FCC ordered application of the Ozark separations procedures to Hawaii. Integration of Rates & Services for the Provision of Communications by Authorized Common Carriers between the United States Mainland & Hawaii & Alaska, Report & Order 81-312 (Docket 21263), 87 F.C.C.2d 18 (1981) [hereafter Order 81-312].1
The new procedures were expected to yield significantly lower interstate phone rates, but only at the price of upward pressure on intrastate rates. To avoid a dramatic impact on local rates, the FCC, AT & T, and HawTel agreed to phase in the new procedures over four years, with full implementation by January 1, 1985. During the transition period, AT & T was to make certain payments or “transitional supplements” to HawTel, thereby reducing the need for immediate intrastate rate relief.
In August 1981, shortly after the integration plan was adopted in FCC Order 81-312, HawTel filed for a local rate increase of $47.6 million. PUC Docket 4306. This proceeding was a predecessor to the one that is the subject of this appeal. The PUC granted only $27.1 million of the requested increase, in part due to a downward 1.1 percent rate-of-return adjustment proposed by the PUC itself. The “Separation Adjustment” represented the difference between intrastate rates resulting from jurisdictional separations calculated under the Ozark Plan and those calculated under Hawaiian Plan II. In re Application of Hawaiian Telephone Company, PUC Decision & Order No. 7412, Docket No. 4306 (Jan.1983); see In re Application of Hawaiian Telephone Company, 67 Haw. 370, 689 P.2d 741, 751-52 (1984). The PUC agreed that the Ozark Plan should be used to establish the rate base, and that an 11.46 percent rate of return was appropriate. It also conceded that the transitional payments from AT & T must be treated as interstate revenues. It considered the special downward adjustment proper, however, in light of the State’s previous support for the transitional rate-integration agreement between AT & T, HawTel, and the FCC. At HawTel’s request, the State had lobbied the FCC for approval of the transition agreement, at least in part because of HawTel’s representations that it would need local rate relief of $30-35 million per year if the agreement were not adopted.2
HawTel appealed the PUC’s decision in Docket 4306 to the Hawaii Supreme Court, arguing that the order in fact nullified the FCC’s 1981 mandate to employ the Ozark Plan. On September 27, 1984, the court upheld the PUC, finding that the PUC had employed appropriate procedures and that it merely had determined the appropriate rate of return on intrastate business, which was within its authority, Application of Hawaiian Telephone Company, 67 Haw. at 385, 689 P.2d at 751. HawTel declined to seek United States Supreme Court review.
While HawTel’s state-court appeal was pending, it filed for another rate increase, with which this appeal is directly concerned. PUC Docket 4588. In Docket 4588, after determining that HawTel would be entitled under the Ozark Plan to some $30 million in new revenues, at a reasonable 11.25 percent rate of return, the PUC made an identical 1.1 percent rate-of-retum [1268]*1268adjustment. In re Application of Hawaiian Telephone Company. Decision & Order No. 8042, Docket No. 4588 (Aug. 1984). It granted HawTel about $20 million in rate relief, $10,507,000 less than its calculations indicated HawTel otherwise should receive. This time, however, the PUC did not expressly compare rates under the Ozark Plan to rates under Hawaiian Plan II, the way that it did to arrive at the 1.1 percent figure in 1981.
HawTel filed suit in federal district court under 47 U.S.C. § 401(b),3 challenging the PUC’s second rate decision in Docket 4588. The downward rate adjustment, HawTel argued, constituted a failure of the PUC to obey FCC Order 81-312. Appellants PUC and Consumer Advocate argued that the district court lacked jurisdiction under § 401(b) and that the PUC’s intrastate rate decision was consistent with FCC Order 81-312. Further, appellants contended that HawTel’s action was barred by the Johnson Act, 28 U.S.C. § 1342,4 and by the doctrine of res judicata. The district court rejected these contentions. Finding that the second 1.1 percent adjustment had the effect of applying Hawaiian Plan II as the basis for separations, the court issued preliminary and permanent injunctions. Hawaiian Telephone Company v. Public Utilities Commission, Civ. No. 84-1306, slip op. (D.Haw. Mar. 13, 1985). Both the PUC and the Consumer Advocate appeal.5
DISCUSSION
I. JURISDICTION UNDER 47 U.S.C. § 401(b)
Questions of subject matter jurisdiction and statutory interpretation are reviewed in this court de novo. Carpenters Southem California Admin. Corp. v. Majestic Housing, 743 F.2d 1341, 1343 (9th Cir.1984); Southeast Alaska Conservation Council, Inc. v. Watson, 697 F.2d 1305, 1309 (9th Cir.1983).
47 U.S.C. § 401(b) states:
If any person fails or neglects to obey any order of the [FCC] other than for the payment of money, while the same is in effect, the [FCC] or any party injured thereby ... may apply to the appropriate district court of the United States for the enforcement of such order. If, after hearing, that court determines that the order was regularly made and duly served, and that the person is in disobedience of the same, the court shall enforce obedience to such order by a writ of injunction or other proper process, mandatory or otherwise, to restrain such person or the officers, agents, or representatives of such person, from further disobedience of such order, or to enjoin upon it or them obedience to the same.
The threshold questions in this case are whether a state utility regulatory body is a “person” and whether, as a rulemaking or nonadjudicatory order, FCC Order 81-312 is an “order” “regularly made” within the meaning of Section 401(b).
A. Whether the PUC is a Person Within the Meaning of the Statute
The definitional section of the Communications Act, 47 U.S.C. § 153, provides that: “[U]nless the context otherwise requires ____ ‘Person’ includes an individual, partnership, association, joint-stock company, trust, or corporation.” Id. § 153(i). The Act defines “state commission” as “the commission, board, or official (by whatever [1269]*1269name designated) which under the laws of any State has regulatory jurisdiction with respect to intrastate operations of carriers.” Id. § 153(t).
In support of their contention that the district court lacked subject matter jurisdiction to grant injunctive relief because the PUC is not a “person” for purposes of § 401(b), appellants principally rely on the Vermont district court’s decision in New England Telephone & Telegraph Company v. Public Service Board of Vermont, 576 F.Supp. 490 (D.Vt.1983), vacated as moot, 794 F.2d 677 (2d Cir.1984).6 In that case, the district court held that because the definition of “person” in § 153(i) includes a series of specific categories that do not encompass state utility commissions, the term “person” should not be interpreted to include such commissions. New England Tel. & Tel., 576 F.Supp. at 493-95.
We disagree with appellants’ argument and the district court’s analysis in New England Tel. & Tel. The design of the statute leads us to conclude that the PUC itself is a person for purposes of § 401(b)7. Section 153(i) does not specify the meaning of “person” in the Communications Act, but instead lists several categories of entities that the term “includes.”8 Thus, the definition of “person” is open-ended and not restricted to the examples enumerated in the statute.9 Furthermore, § 153 expressly gives courts leeway to interpret terms in the Act “[as] the context ... requires.” 47 U.S.C. § 153.
The purposes of § 401(b) and the structure of the Act strongly suggest that the PUC can be enjoined under § 401(b).10 Section 401(b) is the sole mechanism Congress provided for the FCC, the federal government, or private parties to obtain enforcement of FCC orders against noncarriers.11 Under appellants’ interpretation, state regulatory commissions would be exempt from this statutory scheme. Bather than being [1270]*1270required to challenge FCC orders under § 402,12 state commissions would be free to violate FCC orders with impunity. They would be equally immune to private enforcement actions and to enforcement actions brought by the FCC and the federal government.
State commissions have the same opportunity as others to seek review of FCC orders under § 402. See, e.g., State Corporation Commission v. FCC, 787 F.2d 1421 (10th Cir.1986); New York State Commission on Cable TV v. FCC, 669 F.2d 58, 62 n. 8 (2d Cir.1982); North Carolina Utilities Commission v. FCC, 552 F.2d 1036 (4th Cir.), cert. denied, 434 U.S. 874, 98 S.Ct. 222, 54 L.Ed.2d 154 (1977). No logical ground supports excluding state commissions from the group of persons against whom enforcement of orders may be sought. New England Telephone & Telegraph Company v. Public Utilities Commission, 570 F.Supp. 1558, 1569 (D.Me.1983), rev’d on other grounds, 742 F.2d 1 (1st Cir.1984), cert. denied, — U.S. -, 106 S.Ct. 2902, 90 L.Ed.2d 988 (1986). Moreover, since § 401(a), which authorizes district courts to enjoin violations of the Act itself, also contains the term “person,” state commissions would be immune from enforcement of the Act in general.13 It is unlikely that Congress could have intended this result.
We hold that the PUC is a person for purposes of § 401(b).14 We also note that, even if the PUC does not itself constitute a person subject to a § 401(b) enforcement action, the individual Commissioners clearly are “individuals” under § 153(i).15 Because the Commissioners qualify as persons for purposes of § 401(b) injunctions, the district court would not lack subject matter jurisdiction even if the PUC were not a person.
B. Whether FCC Order 81-312 is an “Order” for Purposes of § 401(b)
The next question is whether FCC Order 81-312 constitutes an “order of the Commission” within the meaning of § 401(b).16 Appellants maintain that it does not because the Order resulted from a rulemaking as opposed to an adjudicatory proceeding. The gist of appellants’ argument has been accepted by the First Circuit. New England Telephone & Telegraph Co. v. Public Utilities Commission of Maine, 742 F.2d 1 (1st Cir.1984), cert. denied, — U.S.-, 106 S.Ct. 2902, 90 L.Ed.2d 988 (1986) [hereafter New England Telephone v. Maine ]. In contrast, the Seventh Circuit has affirmed the grant of an injunction under § 401(b) to enforce a nonadjudicatory order. Illinois Bell Telephone Company v. Illinois Commerce Commission, 740 F.2d 566, 571 (7th Cir. 1984).
In New England Telephone v. Maine, the First Circuit based its decision primarily on two grounds. First, the court adopted the distinction between “rules” and “orders” that appears in the Administrative Procedure Act17. Second, it con-[1271]*1271eluded that the central role of the FCC in enforcing the Communications Act, and its sole power to seek injunctions under § 401(a), suggested that the scope for private enforcement under § 401(b) should be narrow.18 The court therefore concluded that an FCC directive that it considered to be the product of a rulemaking proceeding, and that was not specifically directed at the parties against whom enforcement was sought, was not enforceable under § 401(b).
Like several other circuit courts,19 we disagree with the First Circuit’s reasoning. So did the FCC. See New England Telephone v. Maine, 142 F.2d at 10-11.
To begin with, we find no authority supporting the proposition that the APA’s rule-order distinction should be imported into the Communications Act. See 5 U.S.C. § 551 (use of APA’s definitions is mandatory only when APA itself is applicable). In fact, the Communications Act’s legislative history indicates that § 401(b) was modeled in part after § 16(12) of the Interstate Commerce Act, 49 U.S.C. § 16(12) (repealed). The wording of the two provisions is virtually identical, see S.Rep. No. 781, 73d Cong., 2d Sess. 9 (1934). In Pacific Fruit Express Company v. Akron, Canton & Youngstown Railroad, 524 F.2d 1025, 1028-31 (9th Cir.1975), cert. denied, 424 U.S. 911, 96 S.Ct. 1107, 47 L.Ed.2d 315 (1976), we held that § 16(12) authorizes private in junctive actions to enforce ICC rules. The same result would seem to follow for FCC rules under § 401(b).
Second, the language of other sections of the Communications Act shows that Congress did not intend to limit § 401(b) exclusively to adjudicatory orders as the APA defines them. When Congress intended the APA’s definition of a given term to be incorporated into the Communications Act, it said so. E.g., 41 U.S.C. §§ 409(a)-(c) (incorporating APA’s definition of “adjudication”). Congress never provided that the APA’s definition of “order” should extend to § 401(b).20
[1272]*1272We do not believe that our interpretation of § 401(b) displaces the FCC from its central role in the enforcement of the Act. The FCC has broad discretion to act through either case-by-case adjudication or the rulemaking process. See United States v. Southwestern Cable Company, 392 U.S. 157, 180-81, 88 S.Ct. 1994, 2006-07, 20 L.Ed.2d 1001 (1968); see also SEC v. Chenery Corporation, 332 U.S. 194, 202-03, 67 S.Ct. 1575, 1580-81, 91 L.Ed. 1995 (1947) (citing CBS, Inc. v. United States, 316 U.S. 407, 421, 62 S.Ct. 1194, 1202, 86 L.Ed. 1563 (1942)). Thus, the FCC can tailor directives to the needs of particular circumstances. Moreover, the FCC can intervene or file amicus briefs in § 401(b) actions or even invoke the doctrine of primary jurisdiction. See, e.g., United States v. Yellow Freight System, Inc., 762 F.2d 737, 739 (9th Cir.1985) (primary jurisdiction doctrine authorizes suspension of district court proceedings to allow agency to express views on pending issues within agency’s special competence); but see New England Telephone v. Maine, 742 F.2d at 11 (noting that primary jurisdiction doctrine lacks needed clarity and efficiency). These mechanisms help to prevent substantially inconsistent application of FCC rules and serious judicial encroachment on FCC responsibilities.
We need not decide today whether every rule, order, or regulation promulgated by the FCC is an enforceable order under § 401(b), however. The language of the particular order in question, and the proceedings leading up to it, demonstrate that the FCC intended Order 81-312 to require particular actions be taken by the PUC and private carriers providing service to Hawaii.21 Appellant PUC conceded that it must abide by those FCG-mandated separations procedures. Under the circumstances, we conclude that FCC Order 81-312 was appropriately interpreted as an "order” for enforcement by injunction in the district court.
C. Whether FCC Order 81-312 was “Regularly Made”
Appellants’ final challenge to jurisdiction under § 401(b) seizes upon that section’s requirement that an order be “regularly made” by the FCC. They contend that a substantive determination must be made that the FCC had authority to make Order 81-312. Appellants argue that the Commission was without authority to mandate a specific separations method for intrastate ratemaking.
We think that “regularly made” in § 401(b) simply refers to procedural regularity. The substantive validity of FCC orders can be challenged only through actions under § 402(a). ITT World Communications, Inc., 466 U.S. at 468 & n. 5, 104 S.Ct. at 1939 & n. 5 (also noting in dicta that challenges to validity of past agency conduct should be brought through actions for FCC declaratory rulings under doctrine of primary jurisdiction, not in district courts). It would defeat the purpose of § 402(a) to interpret § 401(b) to require a threshold finding of the FCC’s authority to make particular rules. Appellants identify, and we have found, no procedural problems with the promulgation of Order 81-312. Consequently, the district court had subject matter jurisdiction under § 401(b) to issue the injunction.
[1273]*1273II. THE JOHNSON ACT
As their final jurisdictional challenge, appellants argue that the Johnson Act, 28 U.S.C. § 1342, bars HawTel’s action. The four conditions in the Johnson Act are conjunctive; therefore, all four conditions must be present to deprive the district court of jurisdiction.22 DeKalb County v. Southern Bell Telephone & Telegraph Company, 358 F.Supp. 498, 504 (N.D.Ga.1972), aff'd, 478 F.2d 700 (5th Cir.1973); United States v. Public Utilities Commission, 141 F.Supp. 168, 188 (N.D.Cal.1956), aff'd, 355 U.S. 534, 78 S.Ct. 446, 2 L.Ed.2d 470 (1958).
HawTel does not dispute that the final three conditions are met.23 Instead, Haw-Tel argues, and the district court found, that the Johnson Act is inapplicable because HawTel’s action is not based “solely” on a claim of “repugnance of the order to the Federal Constitution.” See 28 U.S.C. § 1342(1). Although appellee’s action is based expressly on 47 U.S.C. § 401(b) and FCC Order 81-312, appellants contend that it is in essence a preemption claim under the Supremacy Clause.
We have construed the term “solely” in § 1342(1) narrowly. The Johnson Act applies “only when [a challenge to a rate order] rests exclusively on ‘repugnance of the order to the Federal Constitution.’ ” International Brotherhood of Electrical Workers v. Public Service Commission, 614 F.2d 206, 210-11 (9th Cir.1980) (quoting 28 U.S.C. § 1342(1)) (emphasis supplied) (upholding federal jurisdiction because the union’s action depended in part on an interpretation of National Labor Relations Act). A claim of preemption does not meet this test. Id. at 211. The district court was correct in holding that the Johnson Act did not bar appellee’s action.
III. RES JUDICATA
The district court also rejected appellants’ contention that HawTel’s claim is barred by res judicata. Appellants assert that HawTel argued that the PUC had misapplied FCC Order 81-312 when it appealed the PUC’s 1981 rate order to the Hawaii Supreme Court.24 Appellants contend that this issue is now foreclosed. Whether res judicata or collateral estoppel bars claims is a mixed question of law and fact subject to de novo review. A & A Concrete, Inc. v. White Mountain Apache Tribe, 781 F.2d 1411, 1414 (9th Cir.), cert. denied, — U.S. -, 106 S.Ct. 2008, 90 L.Ed.2d 659 (1986).
HawTel offers several responses. First, HawTel contends that the Hawaii Supreme Court never squarely addressed its federal claim,25 at least in part because the court exercises only limited review of rate cases. See In re Application of Hawaii Electric Light Company, 60 Haw. 625, 628-29, 594 P.2d 612, 617 (1979). Thus, without citing the case, HawTel appears to invoke the principle of Robinson v. Ariyoshi, 753 F.2d 1468, 1472 (9th Cir. 1985), vacated and remanded on other grounds, — U.S.-, 106 S.Ct. 3269, 91 L.Ed.2d 560 (1986), that collateral estoppel or res judicata effect will not be given to a state court decision when the complaining party did not have a “full and fair opportunity to litigate a claim in state court or where the state court demonstrated inability or unwillingness to protect federal rights.” Id. There is some support in the record for HawTel’s characterization of the [1274]*1274Hawaii Supreme Court's decision, but we need not rule upon this contention because we find Hawtel’s second argument dispositive.
HawTel’s second point is that there is such a disparity between the contexts of the PUC decisions in Dockets 4306 and 4588 that neither res judicata nor collateral estoppel can apply. We agree. The two dockets involve different rate periods, with different rate bases. The causes of action are clearly not the same, and res judicata cannot apply. See Commissioner v. Sunnen, 333 U.S. 591, 597-98, 68 S.Ct. 715, 719-20, 92 L.Ed. 898 (1948) (income tax claims for successive tax years not same cause of action for res judicata purposes). It is true that collateral estoppel may apply and foreclose the litigation of issues that were actually litigated and decided in a previous action, even though the causes of action differ. Id. at 598-99, 68 S.Ct. at 719-20. But in successive rate proceedings, as in successive tax cases, there are strong policy reasons for denying the application of collateral estoppel when variations in either facts or law occur. An issue once decided may create inequities in the continuing administration of the law if applied by estoppel to later years. Id. at 599-600, 68 A.Ct. at 720-21.
Here we conclude that there were sufficient differences between the PUC actions in Dockets 4306 and 4588 to militate against the application of collateral estoppel to the 1.1 percent rate downward rate adjustment. Although essentially the same adjustment was applied, it was applied to different rate periods, with different revenues, different expenses, and different investments. See Papago Tribal Utility Authority v. FERC, 776 F.2d 828, 833 n. 5 (9th Cir.1985), cert. denied, — U.S.-, 106 S.Ct. 1515, 89 L.Ed.2d 913 (1986). When Docket 4306 was decided, HawTel was operating under its transition agreement with AT & T. Among other things, that agreement provided for payments to HawTel to soften the impact on its overall revenues of the mandated shift to the Ozark Plan. In contrast, Docket 4588 involved rates effective January 1, 1985, after the transition agreement had expired.26 If, in this new setting, the 1.1 percent adjustment did violate the FCC separations rule, HawTel should be free to raise the issue, rather than to suffer a continuing violation of a policy set by the FCC. HawTel is not collaterally “appealing” the Hawaii Supreme Court’s decision, but is challenging the lawfulness of the PUC’s action in Docket 4588. PUC Docket 4588 has not been ruled upon by the Hawaii court, or any other court. We conclude that the district court properly rejected the application of res judicata and collateral estoppel.27 .
IV. PREEMPTION OF THE SEPARATIONS FIELD
Reaching the merits, appellant Consumer Advocate contends that FCC Order 81-312 did not preempt state regulation of separations procedures and that the PUC’s use of state-developed procedures was perfectly proper for intrastate ratemaking. This argument raises a question of law reviewed here de novo. United States v. McConney, 728 F.2d 1195, 1201 (9th Cir.) (en banc), [1275]*1275cert. denied, 469 U.S. 824, 105 S.Ct. 101, 83 L.Ed.2d 46 (1984).
Appellants concede the FCC’s plenary authority over separations procedures, but argue in their Joint Brief that the FCC has not exercised this power. They point to the absence of an express statement of intention to preempt the field of separations for intrastate ratemaking purposes in FCC Order 81-312.28 They argue that the applicable test for preemption is whether both the state and federal regulations “can be enforced without impairing the federal superintendence of the field.” Florida Lime & Avocado Growers, Inc. v. Paul, 373 U.S. 132, 142, 83 S.Ct. 1210, 1217, 10 L.Ed.2d 248 (1963).
Appellants’ argument overlooks the extent to which separations for interstate ratemaking and separations for intrastate ratemaking are two sides of the same coin.29 When the same plant and equipment is used to provide both interstate and intrastate services and different authorities set rates for these respective services, cost and investment must be apportioned uniformly in order to establish fair rates. See The Minnesota Rate Cases, 230 U.S. 352, 435, 33 S.Ct. 729, 755, 57 L.Ed. 1511 (1913); Washington Utilities & Transportation Commission v. FCC, 513 F.2d 1142, 1146 (9th Cir.), cert. denied, 423 U.S. 836, 96 S.Ct. 62, 46 L.Ed.2d 54 (1975). If the sum of the intrastate and interstate portions for rate-base allocation purposes were not 100 percent,
some costs of plant and expenses would not be included in the rate computations of either [the PUC or the FCC]. In [that] situation ..., the “carrier may be deprived of a fair rate of return when interstate and intrastate jurisdictions are both taken into account.”
Application of Hawaiian Tel. Co., 67 Haw. at 385-88, 689 P.2d at 751-52 (quoting New England Tel. & Tel. Co. v. Public Utilities Comm’n, 448 A.2d 272, 298 (Me. 1982)). See also Illinois Bell, 740 F.2d at 567; Washington Utilities & Transportation Commission, 513 F.2d at 1146-47 (recognizing complementary nature of the separations process).
The Communications Act empowers the FCC to prescribe uniform separations procedures. Illinois Bell, 740 F.2d at 567; see 47 U.S.C. § 221(c) (granting FCC authority to classify property for interstate or foreign telephone toll service); id. § 410(c) (requiring use of Federal-State Joint Board for separations rulemaking). These statutes evince a congressional intent that FCC separations orders control the state regulatory bodies, because a nationwide telecommunications system with dual intrastate and interstate rates can operate effectively only if one set of separations procedures is employed. E.g., State Corporation Commission v. FCC, 787 F.2d 1421, 1426-27 (10th Cir.1986) (citing cases); see Louisiana Public Service, 106 S.Ct. at 1902 (citing Smith v. Illinois Bell Telephone Co., 282 U.S. 133, 51 S.Ct. 65, 75 L.Ed. 255 (1930)); S.Rep. No. 92-362, 92d Cong., 1st Sess., reprinted in 1971 U.S. Code Cong. & Admin.News 1511, 1513, 1515 (noting need to preserve federal superintendence in the separations field, citing Smith v. Illinois Bell, supra); see also NARUC v. FCC, 746 F.2d 1492, 1499-1501 (D.C.Cir.1984); In re Establishment of Interstate Toll Settlements & Jurisdictional Separations Requiring the Use of Seven Calendar Day Studies by the Florida Pub. Serv. Comm’n, Memorandum Opinion & Order on Reconsideration (Docket No. 84-268), 98 F.C.C.2d 777-84 (1984); In re AT & T & the Associated Bell System Companies Charges for Interstate & Foreign Communication Service, Interim Decision & Order (Docket Nos. 16258 & 15011), 9 F.C.C.2d 30, 90-91 (1967).
[1276]*1276The FCC’s statements during the lengthy Ozark Plan proceedings indicate a desire to adopt a separations scheme agreeable to as many states as possible because that scheme will apply to the entire nation. E.g., Prescription of Procedures for Separating and Allocating Plant Investment, Operating Expenses, Taxes and Reserves Between the Intrastate and Interstate Operations of Telephone Companies, Report & Order 70-1151 (Docket 18866), 26 F.C. C.2d 247, 257 (1970). In 1972, the FCC began efforts to integrate Hawaii “into the established rate scheme for communications services applicable to the Mainland.” Docket No. 16495, 35 F.C.C.2d at 856-57. The FCC extended Ozark to Hawaii as a central part of that rate scheme in Order 81-312, expressly citing its separations authority under § 221(c) and following the procedure set forth by § 410(c).
This history, the statutory framework underlying it, and the need for consistent apportionment between interstate and intrastate operations, are sufficient to convince us that FCC Order 81-312 necessarily preempted any independent separations procedures of the Hawaii PUC.
V. LOUISIANA PUBLIC SERVICE AND § 152(b)
In its recent decision in Louisiana Public Service, the Supreme Court held that § 152(b) of the Act bars “federal preemption of state regulation over depreciation of dual jurisdiction property for intrastate ratemaking purposes.” 106 S.Ct. at 1904. Section 152(b) provides:
[Njothing in this chapter shall be construed to apply or to give the [FCC] jurisdiction with respect to (1) charges, classifications, practices, services, facilities, or regulations for or in connection with intrastate communication service by wire or radio of any carrier____
47 U.S.C. § 152(b). Appellants argue that this provision, and the Louisiana Public Service decision, support their view that the FCC cannot dictate separations practices to the states for use in their intrastate ratemaking. We disagree.
The Supreme Court made it quite clear in Louisiana Public Service that federal separations procedures were an essential prerequisite to the creation of independent spheres of federal and state power over communications:
The Communications Act not only establishes dual state and federal regulation of telephone service; it also recognizes that jurisdictional tensions may arise as a result of the fact that interstate and intrastate service are provided by a single integrated system. Thus, the Act itself establishes a process designed to resolve what is [sic] known as “jurisdictional separations” matters, by which process it may be determined what portion of an asset is employed to produce or deliver interstate as opposed to intrastate service. 47 U.S.C. § 410(c). Because the separations process literally separates costs such as taxes and operating expenses between interstate and intrastate service, it facilitates the creation or recognition of distinct spheres of regulation.
Louisiana Public Service, 106 S.Ct. at 1902. See also id. at 1899 (“the jurisdictional limitations placed on the FCC by § 152(b), coupled with the fact that the Act provides for a ‘separations’ proceeding to determine the portions of a single asset that are used for interstate and intrastate service, 47 U.S.C. § 410(c), answer” arguments for preemption of depreciation).
Thus, it is only after a uniform separations formula has been applied that a state’s independent depreciation rule for intrastate ratemaking can be protected from federal preemption. See Smith v. Illinois Bell, 282 U.S. at 148, 51 S.Ct. at 68. The Supreme Court’s decision in Louisiana Public Service accordingly supports our conclusion that the FCC separations procedures authorized by § 410(c) of the Act bind the states, and that § 152(b) does not stand in the way.30
[1277]*1277VI. PUC DISOBEDIENCE OF THE FCC ORDER
Finally, appellants contend that the PUC did not disobey the FCC order. The district court found that it did. We review factual findings for clear error. E.g., United States v. McConney, 728 F.2d at 1201.
We have already determined that the FCC properly preempted the separations field, employing the authority granted by the Communications Act. No one disputes the authority of a state PUC to establish a reasonable rate of return for utilities within its jurisdiction. But, as the district court found, the “appropriate adjustment” here was a fairly transparent and improper attempt to circumvent the FCC mandate. Cf. Aloha Airlines, Inc. v. Director of Taxation, 464 U.S. 7, 12-13, 104 S.Ct. 291, 294-95, 78 L.Ed.2d 10 (1983) (state could not circumvent preemptive federal Act prohibiting gross receipts tax on airlines by calling its tax a “property tax measured by gross receipts”). The Supremacy Clause does not countenance state policies — in this case, a state ratemaking ruling — that may produce results inconsistent with the objective of a federal statute. E.g., Maryland v. Louisiana, 451 U.S. 725, 747, 101 S.Ct. 2114, 2129, 68 L.Ed.2d 576 (1981).
The undisputed evidence is that, while the PUC initially used the Ozark Plan to calculate rates, it then adjusted rates downward by 1.1 percent. The PUC arrived at its 1.1 percent “Adjustment for Change in Separation Plan” by comparing 1981 rates under the Ozark Plan and under Hawaiian Plan II. It also took into account the transitional payments from AT & T even though it acknowledged that these had to be considered as interstate revenues. The district court did not clearly err in finding that this adjustment was an attempt to nullify the FCC’s Ozark separations plan. Although no new comparison was performed in 1984 in Docket 4588, the PUC expressly carried over the 1.1 percent adjustment even after it found that 11.25 percent was a reasonable rate of return and that a rate increase of $30 million was necessary to achieve the 11.25 percent return.31 Appellants offered only the explanation that the 1.1 percent adjustment resulted from the PUC’s determination, within its proper authority, that the adjustment was “necessary, fair and reasonable.” PUC Decision & Order No. 8042, Docket No. 4588 at 15 (noting that adjustment would be treated as an adjustment to expenses). No support for such a finding appears in the PUC order or in evidence, however.
Rather than simply accept the PUC’s statements that it was applying the Ozark Plan, the district court properly considered the effect of the PUC’s ruling to determine whether it conflicted with federal law. See Perez v. Campbell, 402 U.S. 637, 652, 91 S.Ct. 1704, 1712, 29 L.Ed.2d 233 (1971); New York State Commission on Cable TV v. FCC, 669 F.2d 58, 62 (2d Cir.1982). Reviewing the record, we conclude that the district court committed no clear error in finding that “[t]he so-called ‘appropriate adjustment’ ... in Docket No. 4588 was calculated solely and precisely on the difference between the Hawaiian Plan II and Ozark Separations formulas.” Judgment for Permanent Injunction II13. That finding supports a conclusion that PUC violated the FCC-imposed Ozark Plan.
CONCLUSION
The district court’s injunction is authorized under § 401(b) and its decision to accord preemptive weight to FCC Order 81-312 does not violate the dual regulatory system prescribed under the Communications Act. The court did not clearly err in finding that the PUC’s rate-of-retum ad[1278]*1278justment was in effect a thinly veiled attempt to depart from the required separation of plant and expenses between interstate and intrastate use. The PUC clearly has supreme authority with regard to intrastate ratemaking; but the PUC is not entitled to define boundaries of its intrastate sphere that are different from those established by the valid FCC order. Nor can the PUC accomplish by subterfuge what it could not, by its own admission, do directly.
The order of the district court enjoining the PUC and its Commissioners is therefore AFFIRMED.