Petitioner Secretary of the Interior granted oil and gas leases to petitioner oil companies in the Norton Sound (Lease Sale 57) and Navarin Basin (Lease Sale 83) areas of the Bering Sea under the Outer Continental Shelf Lands Act (OCSLA), 67 Stat. 462, as amended, 43 U.S.C. § 1331 et seq. (1982 ed. and Supp. III). The Court of Appeals for the Ninth Circuit directed the entry of a preliminary injunction against all activity in connection with the leases because it concluded that it was likely that the Secretary had failed to comply with § 810 of the Alaska National Interest Lands Conservation Act (ANILCA), 94 Stat. 2371, 16 U.S.C. § 3120, prior to issuing the leases. We granted certiorari, 476 U.S. 1157, 106 S.Ct. 2274, 90 L.Ed.2d 717, and we now reverse.1

* When the Secretary of the Interior proposed Outer Continental Shelf (OCS) Lease Sale 57, the Alaska Native villages of Gambell and Stebbins sought to enjoin him from proceeding with the sale, claiming that it would adversely affect their aboriginal rights to hunt and fish on the OCS and that the Secretary had failed to comply with ANILCA § 810(a), 16 U.S.C. § 3120(a), which provides protection for natural resources used for subsistence in Alaska.2 The District Court denied their motion for a preliminary injunction and thereafter granted summary judgment in favor of the Secretary and oil company intervenors, holding that the villagers had no aboriginal rights on the OCS and that ANILCA did not apply to the OCS.3

The Court of Appeals for the Ninth Circuit affirmed the District Court's ruling on aboriginal rights, although on different grounds, and reversed the ruling on the scope of ANILCA § 810. People of Gambell v. Clark, 746 F.2d 572 (1984) (Gambell I ). With respect to the claim of aboriginal rights, the court assumed without deciding that the villagers once had aboriginal rights to hunt and fish in the Norton Sound,4 but concluded that these rights had been extinguished by § 4(b) of the Alaska Native Claims Settlement Act (ANCSA), 85 Stat. 690, 43 U.S.C. § 1603(b). That section provides:

"All aboriginal titles, if any, and claims of aboriginal title in Alaska based on use and occupancy, including submerged land underneath all water areas, both inland and offshore, and including any aboriginal hunting or fishing rights that may exist, are hereby extinguished." (Emphasis added.)

The Court of Appeals construed the phrase "in Alaska" to mean "the geographic region, including the contiguous continental shelf and the waters above it, and not merely the area within the strict legal boundaries of the State of Alaska." 746 F.2d, at 575. Finding the phrase ambiguous, the court examined the legislative history and concluded that Congress wrote the extinguishment provision broadly "to accomplish a complete and final settlement of aboriginal claims and avoid further litigation of such claims." Ibid. The court then concluded that ANILCA § 810 had the same geographical scope as ANCSA § 4(b):

"[The villages] make a compelling argument that the provisions of Title VIII of [ANILCA] protecting subsistence uses were intended to have the same territorial scope as provisions of the earlier Claims Settlement Act extinguishing Native hunting and fishing rights. The two statutory provisions are clearly related. When Congress adopted the Claims Settlement Act it was aware that extinguishing Native rights might threaten subsistence hunting and fishing by Alaska Natives. . . . It is a reasonable assumption that Congress intended the preference and procedural protections for subsistence uses mandated by Title VIII of [ANILCA] to be co-extensive with the extinguishment of aboriginal rights that made those measures necessary." 746 F.2d, at 579-580.

The court found support for this view in ANILCA's legislative history. But, according to the Court of Appeals, "[t]he most compelling reason for resolving the ambiguous language of Title VIII in favor of coverage of outer continental shelf lands and waters is that Title VIII was adopted to benefit the Natives." Id., at 581. The court acknowledged the familiar rule of statutory construction that doubtful expressions must be resolved in favor of Indians. See Alaska Pacific Fisheries v. United States, 248 U.S. 78, 89, 39 S.Ct. 40, 41-42, 63 L.Ed. 138 (1918). It then remanded to the District Court the questions whether the Secretary had substantially complied with ANILCA § 810 in the course of complying with other environmental statutes,5 and if not, whether the leases should be voided.

In compliance with the Court of Appeals' decision, the Secretary prepared a postsale evaluation of possible impacts on subsistence uses from Lease Sale 57.6 The Secretary found that the execution of the leases, which permitted lessees to conduct only limited preliminary activities on the OCS, had not and would not significantly restrict subsistence uses. He further found that the exploration stage activities, including seismic activities and exploratory drilling, that had occurred in Norton Sound had not significantly restricted subsistence uses and were not likely to do so in the future. Finally, he found that, if development and production activities were ever conducted, which was not likely, they might, in the event of a major oilspill, significantly restrict subsistence uses for limited periods in limited areas.7

In April 1985, the villages sought a preliminary injunction in the District Court against exploratory activities in Norton Sound. At the same time, the village of Gambell, joined by Nunam Kitlutsisti, an organization of Yukon Delta Natives, filed a complaint seeking to void Lease Sale 83 and to enjoin imminent exploratory drilling in the Navarin Basin. The District Court consolidated the motions for preliminary injunctions and denied them. It found that respondents had established a strong likelihood of success on the merits. Although the Secretary, in the EIS's for the Five Year Leasing Plan and for the Norton Sound and Navarin Basin Lease Sales, had evaluated in some detail the effect of OCS oil and gas development on subsistence resources and had considered alternatives which would reduce or eliminate the impact on these resources, the Secretary failed to comply with ANILCA because "he did not have the policy precepts of ANILCA in mind at the time of evaluation." App. to Pet. for Cert. in No. 85-1239, pp. 57a-58a. And with respect to the postsale evaluation for Lease Sale 57, the District Court concluded that because development and production activities, if they ever occurred, could significantly restrict subsistence uses in certain areas, the Secretary was required to conduct the hearing and make the findings required by §§ 810(a)(1)-(3) prior to conducting the lease sale. Nevertheless, the court concluded that injunctive relief was not appropriate based on the following findings:

"(1) That delay in the exploration of the OCS may cause irreparable harm to this nation's quest for new oil resources and energy independence. Expedited exploration as a policy is stated in OCSLA. See 43 U.S.C. § 1332(3);

"(2) That exploration will not significantly restrict subsistence resources; and

"(3) That the Secretary continues to possess power to control and shape the off-shore leasing process. Therefore, if the ANILCA subsistence studies require alteration of the leasing conditions or configuration the Secretary will be able to remedy any harm caused by the violation." Id., at 62a-63a.

Accordingly, applying the traditional test for a preliminary injunction, the court concluded that the balance of irreparable harm did not favor the movants; in addition, the public interest favored continued oil exploration and such exploration in this case would not cause the type of harm that ANILCA was designed to prevent.

Respondents appealed from the District Court's denial of a preliminary injunction. The Ninth Circuit reversed. People of Gambell v. Hodel, 774 F.2d 1414 (1985) (Gambell II ). The court, agreeing that the villages had established a strong likelihood of success on the merits, concluded that the District Court had not properly balanced irreparable harm and had not properly evaluated the public interest. Relying on its earlier decision in Save Our Ecosystems v. Clark, 747 F.2d 1240, 1250 (1984), the court stated: " 'Irreparable damage is presumed when an agency fails to evaluate thoroughly the environmental impact of a proposed action.' " 774 F.2d, at 1423. It ruled that "injunctive relief is the appropriate remedy for a violation of an environmental statute absent rare or unusual circumstances." Ibid. "Unusual circumstances" are those in which an injunction would interfere with a long-term contractual relationship, Forelaws on Board v. Johnson, 743 F.2d 677 (CA9 1984), or would result in irreparable harm to the environment, American Motorcyclist Assn. v. Watt, 714 F.2d 962, 966 (CA9 1983). 774 F.2d, at 1423-1425. The court found no such circumstances in the instant case. The Ninth Circuit also concluded that the policy declared in OCSLA to expedite exploration of the OCS had been superseded by ANILCA's policy to preserve the subsistence culture of Alaska Natives. Finally, the court rejected arguments that it was improper to apply Gambell I retroactively to Lease Sale 83.

Petitioners assert that the Ninth Circuit erred in directing the grant of a preliminary injunction. We addressed a similar contention in Weinberger v. Romero-Barcelo, 456 U.S. 305, 102 S.Ct. 1798, 72 L.Ed.2d 91 (1982). The District Court in that case found that the Navy had violated the Federal Water Pollution Control Act (FWPCA), 33 U.S.C. § 1251 et seq. (1982 ed. and Supp. III), by discharging ordnance into the sea without a permit. 456 U.S., at 307-308, 102 S.Ct., at 1800-1801. The court ordered the Navy to apply for a permit but refused to enjoin weapons-training operations during the application process because the Navy's "technical violations" were not causing any "appreciable harm" to the quality of the water and an injunction would cause grievous harm to the Navy's military preparedness and therefore to the Nation. Id., at 309-310, 102 S.Ct., at 1801-1802. The First Circuit reversed and directed the District Court to enjoin all Navy activities until it obtained a permit, concluding that the traditional equitable balancing of competing interests was inappropriate where there was an absolute statutory duty to obtain a permit. Id., at 310-311, 102 S.Ct., at 1802-1803. We reversed, acknowledging at the outset the fundamental principle that an injunction is an equitable remedy that does not issue as of course. Id., at 311, 102 S.Ct., at 1802. We reviewed the well-established principles governing the award of equitable relief in federal courts. Id., at 311-313, 102 S.Ct., at 1802-1804. In brief, the bases for injunctive relief are irreparable injury and inadequacy of legal remedies. In each case, a court must balance the competing claims of injury and must consider the effect on each party of the granting or withholding of the requested relief. Although particular regard should be given to the public interest, "[t]he grant of jurisdiction to ensure compliance with a statute hardly suggests an absolute duty to do so under any and all circumstances, and a federal judge sitting as chancellor is not mechanically obligated to grant an injunction for every violation of law." Id., at 313, 102 S.Ct., at 1803. Finally, we stated:

"Of course, Congress may intervene and guide or control the exercise of the courts' discretion, but we do not lightly assume that Congress has intended to depart from established principles. . . . 'Unless a statute in so many words, or by a necessary and inescapable inference, restricts the court's jurisdiction in equity, the full scope of that jurisdiction is to be recognized and applied.' " Ibid. (quoting Porter v. Warner Holding Co., 328 U.S. 395, 398, 66 S.Ct. 1086, 1089, 90 L.Ed. 1332 (1946)).

Applying these principles, we concluded that the purpose of the FWPCA—to restore and maintain the integrity of the Nation's waters—would not be undermined by allowing the statutory violation to continue during the permit application process because the ordnance was not polluting the water. 456 U.S., at 314-315, 102 S.Ct., at 1804-1805. The First Circuit had erroneously focused on the integrity of the permit process rather than on the integrity of the Nation's water. Moreover, the permit process was not completely circumvented since the District Court ordered the Navy to apply for a permit. An injunction against all discharges was not the only means of ensuring compliance with the Act8 and we found nothing in the Act's language and structure or legislative history which suggested that Congress intended to deny courts their traditional equitable discretion.9

We see nothing which distinguishes Romero-Barcelo from the instant case. The purpose of ANILCA § 810 is to protect Alaskan subsistence resources from unnecessary destruction. Section 810 does not prohibit all federal land use actions which would adversely affect subsistence resources but sets forth a procedure through which such effects must be considered and provides that actions which would significantly restrict subsistence uses can only be undertaken if they are necessary and if the adverse effects are minimized. There is no clear indication in § 810 that Congress intended to deny federal district courts their traditional equitable discretion in enforcing the provision, nor are we compelled to infer such a limitation. Like the First Circuit in Romero-Barcelo, the Ninth Circuit erroneously focused on the statutory procedure rather than on the underlying substantive policy the process was designed to effect—preservation of subsistence resources. The District Court's refusal to issue a preliminary injunction against all exploration activities did not undermine this policy. The District Court, after reviewing the EIS's for the Secretary's Five Year Leasing Plan and for Lease Sales 57 and 83, as well as the § 810 study prepared after Gambell I, expressly found that exploration activities would not significantly restrict subsistence uses.10 The Court of Appeals did not conclude that this factual finding was clearly erroneous. The District Court also found that "the Secretary continues to possess power to control and shape the off-shore leasing process," App. to Pet. for Cert. in No. 85-1239, p. 63a, referring to the four distinct stages under OCSLA, particularly the requirement for secretarial approval of a development and production plan, 43 U.S.C. § 1351. See n. 6, supra. The Court of Appeals did not dispute that the Secretary could meaningfully comply with ANILCA § 810 in conjunction with his review of production and development plans. Instead, the court stated that "[i]rreparable damage is presumed when an agency fails to evaluate thoroughly the environmental impact of a proposed action." 774 F.2d, at 1423 (emphasis added). This presumption is contrary to traditional equitable principles and has no basis in ANILCA. Moreover, the environment can be fully protected without this presumption. Environmental injury, by its nature, can seldom be adequately remedied by money damages and is often permanent or at least of long duration, i.e., irreparable. If such injury is sufficiently likely, therefore, the balance of harms will usually favor the issuance of an injunction to protect the environment. Here, however, injury to subsistence resources from exploration was not at all probable. And on the other side of the balance of harms was the fact that the oil company petitioners had committed approximately $70 million to exploration to be conducted during the summer of 1985 which they would have lost without chance of recovery had exploration been enjoined. Id., at 1430.

We acknowledged in Romero-Barcelo the important role of the "public interest" in the exercise of equitable discretion. The District Court concluded that the public interest in this case favored continued oil exploration, given OCSLA's stated policy11 and the fact that "such exploration will not cause the type of harm, a restriction in subsistence uses or resources, that ANILCA was designed to prevent." App. to Pet. for Cert. in No. 85-1239, p. 63a. The Court of Appeals concluded, however, that the public interest favored injunctive relief because the interests served by federal environmental statutes, such as ANILCA, supersede all other interests that might be at stake. We do not read ANILCA to have repealed OCSLA. Congress clearly did not state in ANILCA that subsistence uses are always more important than development of energy resources, or other uses of federal lands; rather, it expressly declared that preservation of subsistence resources is a public interest and established a framework for reconciliation, where possible, of competing public interests.12

Accordingly, the Ninth Circuit erred in directing the issuance of a preliminary injunction.

Petitioners also contend that the Court of Appeals erred in holding that ANILCA § 810 applies to the OCS. We agree. By its plain language, that provision imposes obligations on federal agencies with respect to decisions affecting use of federal lands within the boundaries of the State of Alaska. Section 810 applies to "public lands." Section 102 of ANILCA, 16 U.S.C. § 3102, defines "public lands," and included terms, for purposes of the Act13 as follows:

"(1) The term 'land' means lands, waters, and interests therein.

"(2) The term 'Federal land' means lands the title to which is in the United States after December 2, 1980.

"(3) The term 'public lands' means land situated in Alaska which, after December 2, 1980, are Federal lands, except [land selected by the State of Alaska or granted to the State under the Alaska Statehood Act, 72 Stat. 339, or any other provision of federal law, land selected by a Native Corporation under ANCSA, and lands referred to in ANCSA § 19(b), 43 U.S.C. § 1618(b) ]." (Emphasis added.)

The phrase "in Alaska" has a precise geographic/political meaning. The boundaries of the State of Alaska can be delineated with exactitude. The State of Alaska was "admitted into the Union on an equal footing with the other States," and its boundaries were defined as "all the territory, together with the territorial waters appurtenant thereto, now included in the Territory of Alaska." Alaska Statehood Act (Statehood Act) §§ 1, 2, 72 Stat. 339. The Submerged Lands Act of 1953, 67 Stat. 29, as amended, 43 U.S.C. § 1301 et seq. (1982 ed. and Supp. III), was made applicable to the State. Statehood Act § 6(m), 72 Stat. 343. Under § 4 of the Submerged Lands Act, 43 U.S.C. § 1312, the seaward boundary of a coastal State extends to a line three miles from its coastline. At that line, the OCS commences. OCSLA § 2(a), 43 U.S.C. § 1331(a). By definition, the OCS is not situated in the State of Alaska. Nevertheless, the Ninth Circuit concluded that "in Alaska" should be construed in a general, "nontechnical" sense to mean the geographic region of Alaska, including the Outer Continental Shelf.14 746 F.2d, at 579. We reject the notion that Congress was merely waving its hand in the general direction of northwest North America when it defined the scope of ANILCA as "Federal lands" "situated in Alaska." Although language seldom attains the precision of a mathematical symbol, where an expression is capable of precise definition, we will give effect to that meaning absent strong evidence that Congress actually intended another meaning. "[D]eference to the supremacy of the Legislature, as well as recognition that Congressmen typically vote on the language of a bill, generally requires us to assume that 'the legislative purpose is expressed by the ordinary meaning of the words used.' " United States v. Locke, 471 U.S. 84, 95, 105 S.Ct. 1785, 1793, 85 L.Ed.2d 64 (1985) (quoting Richards v. United States, 369 U.S. 1, 9, 82 S.Ct. 585, 590, 7 L.Ed.2d 492 (1962)). This is not that "exceptional case" where acceptance of the plain meaning of a word would "thwart the obvious purpose of the statute." Griffin v. Oceanic Contractors, Inc., 458 U.S. 564, 571, 102 S.Ct. 3245, 3250, 73 L.Ed.2d 973 (1982) (internal quotations omitted).15

Nothing in the language or structure of ANILCA compels the conclusion that "in Alaska" means something other than "in the State of Alaska." The subsistence-protection provisions of the statute must be viewed in the context of the Act as a whole.16 ANILCA's primary purpose was to complete the allocation of federal lands in the State of Alaska,17 a process begun with the Statehood Act in 1958 and continued in 1971 in ANCSA.18 To this end, it provided for additions to the National Park System, National Wildlife Refuge System, National Forest System, National Wild and Scenic Rivers System, and National Wilderness Preservation System, and also provided for the establishment of a National Conservation Area and National Recreation Area, within the State of Alaska. Titles II-VII, 94 Stat. 2377-2422. The Act also provided means to facilitate and expedite the conveyance of federal lands within the State to the State of Alaska under the Statehood Act and to Alaska Natives under ANCSA. Titles IX and XIV, 94 Stat. 2430-2448, 2491-2549. The remaining federal lands within the State were left available for resource development and disposition under the public land laws. The other provisions of ANILCA have no express applicability to the OCS and need not be extended beyond the State of Alaska in order to effectuate their apparent purposes.19 It is difficult to believe that Congress intended the subsistence protection provisions of Title VIII, alone among all the provisions in the Act, to apply to the OCS. It is particularly implausible because the same definition of "public lands" which defines the scope of Title VIII applies as well to the rest of the statute (with the exceptions noted at n. 13, supra ).

There is a lone reference to the OCS in the statute, in § 1001(a), 16 U.S.C. § 3141(a), and it is for the purpose of ensuring that the provision does not apply to the OCS.20 Section 1001 provides for a study of oil and gas resources, wilderness characteristics, and wildlife resources of the "North Slope":

"(a) The Secretary shall initiate and carry out a study of all Federal lands (other than submerged lands on the Outer Continental Shelf) in Alaska north of 68 degrees north latitude and east of the western boundary of the National Petroleum Reserve—Alaska, other than lands included in the National Petroleum Reserve—Alaska and in conservation system units established by this Act."

The Secretary suggests that Congress included the parenthetical excluding the OCS out of an abundance of caution because "North Slope" is defined in a related statute—the Alaska Natural Gas Transportation Act of 1976, 15 U.S.C. § 719 et seq. (1982 ed. and Supp. III)—to include the OCS. See 15 U.S.C. § 719b. Whatever the reason for caution, it is apparent from ANILCA § 1008(a), 16 U.S.C. § 3148(a), that Congress did not intend "Federal lands in Alaska" to include the OCS despite the parenthetical in § 1001(a). Section 1008(a) requires the Secretary to "establish, pursuant to the Mineral [Lands] Leasing Act of 1920, as amended [30 U.S.C. § 181 et seq. (1982 ed. and Supp. III) ], an oil and gas leasing program on the Federal lands of Alaska not subject to the study required by section 1001 of this Act, other than lands included in the National Petroleum Reserve—Alaska." (Emphasis added.) Congress clearly did not intend this program to extend to the OCS; OCSLA, rather than the Mineral Lands Leasing Act, governs mineral leasing on the OCS. See 43 U.S.C. § 1333(a)(1).

Title VIII itself suggests that it does not apply to the OCS. Section 810 places the duty to perform a subsistence evaluation on "the head of the Federal agency having primary jurisdiction over such lands." Unlike onshore lands, no federal agency has "primary jurisdiction" over the OCS; agency jurisdiction turns on the particular activity at issue. See G. Coggins & C. Wilkinson, Federal Public Land and Resources Law 434 (1981).

The similarity between the language of ANILCA and its predecessor statutes, the Statehood Act and ANCSA, also refutes the contention that Congress intended "Alaska" to include the OCS. In the Statehood Act, Congress provided that the State of Alaska could select over 100 million acres from the vacant and unreserved "public lands of the United States in Alaska" within 25 years of its admission. Statehood Act § 6(b), 72 Stat. 340. Similarly, in ANCSA, Congress allowed Native Alaskans to select approximately 40 million acres of "Federal lands and interests therein located in Alaska," with the exception of federal installations and land selections of the State of Alaska under the Statehood Act. 43 U.S.C. §§ 1602(e), 1610(a), 1611. We agree with the Secretary that "[i]t is inconceivable that Congress intended to allow either the State of Alaska or Native Alaskans to select portions of the OCS—'a vital national resource reserve held by the [government] for the public' (43 U.S.C. 1332(3))." Brief for Petitioners in No. 85-1406, p. 33. Clearly, the purpose of these provisions was to apportion the land within the boundaries of the State of Alaska. The nearly identical language in ANILCA strongly suggests a similar scope for that statute.

When statutory language is plain, and nothing in the Act's structure or relationship to other statutes calls into question this plain meaning, that is ordinarily "the end of the matter." Chevron U.S.A. Inc. v. Natural Resources Defense Council, Inc., 467 U.S. 837, 842, 104 S.Ct. 2778, 2781, 81 L.Ed.2d 694 (1984). "Going behind the plain language of a statute in search of a possibly contrary congressional intent is a step to be taken cautiously even under the best of circumstances." United States v. Locke, 471 U.S., at 95-96, 105 S.Ct., at 1793 (internal quotations omitted). ANILCA's legislative history does not evidence a congressional intent contrary to our reading of the statutory language. Significantly, the legislative history nowhere expressly indicates that the subsistence provisions apply to the OCS. The Ninth Circuit relied on a number of remarks made during the floor debates which were not specifically addressed to the scope of ANILCA in general or the subsistence provisions in particular. 746 F.2d, at 579. The central issue of the floor debates was the appropriate balance between exploitation of natural resources, particularly energy resources, and dedication of land to conservation units. A number of Congressmen addressed the amount of oil expected to be recovered from the OCS offshore of Alaska in the context of this balancing and, in doing so, referred to "Alaska" in a manner which included the OCS. Representative Udall, Chairman of the House Committee on Interior and Insular Affairs, and floor manager of the bill, for example, sought to assure Members that the bill he favored did not inordinately restrict energy development:

"The experts tell us that most of the oil and gas is not going to be from onshore. . . . Offshore in Alaska there are 203 million acres of sedimentary basin. Let me tell the Members how much of that is put out of production by this bill so that they cannot get it. The answer is zero. Every single acre of offshore oil sedimentary basin potential in Alaska is going to be open for oil drilling and prospecting. The State owns some of it beneath the high water mark, and the Federal Government owns the rest.

"Under other legislation those submerged lands are open, are going to be explored and developed, and that should be 203 million acres." 125 Cong. Rec. 9900 (1979) (emphasis added); see also id., at 11128.

This casual use of the phrase "in Alaska" in a floor debate does not carry the same weight that it does in the definitional section of the statute.21 Spoken language is ordinarily less precise than written language; Representative Udall could easily have intended to say "offshore of Alaska." Indeed, the obvious thrust of his statement was that ANILCA does not apply to the OCS; rather, OCSLA governs offshore oil development. Numerous statements by other legislators reveal a common understanding consistent with the plain meaning of the statutory language—that ANILCA simply "has nothing to do with the Outer Continental Shelf," id., at 11170 (remarks of Rep. Emery).22

Finally, we reject the Ninth Circuit's reliance on the familiar rule of statutory construction that doubtful expressions must be resolved in favor of Indians. 746 F.2d, at 581. There is no ambiguity here which requires interpretation. "The canon of construction regarding the resolution of ambiguities . . . does not permit reliance on ambiguities that do not exist; nor does it permit disregard of the clearly expressed intent of Congress." South Carolina v. Catawba Indian Tribe, 476 U.S. 498, 506, 106 S.Ct. 2039, 2044, 90 L.Ed.2d 490 (1986).

The judgment of the Ninth Circuit with respect to the entry of a preliminary injunction and the applicability of ANILCA § 810 to the OCS is reversed. We do not decide here the scope of ANCSA § 4(b). Respondents' cross-petition on this issue, No. 85-1608, is granted, the Court of Appeals' judgment that § 4(b) extinguished aboriginal rights on the OCS is vacated, and this question is remanded to the Court of Appeals for decision in light of this opinion.

It is so ordered.

Justice STEVENS, with whom Justice SCALIA joins, concurring in part and concurring in the judgment.

Given the Court's holding that § 810 of the Alaska National Interest Lands Conservation Act (ANILCA), 94 Stat. 2371, 16 U.S.C. § 3120, does not apply to the Outer Continental Shelf, it is unnecessary to decide whether the Court of Appeals applied the proper standard in determining the availability of injunctive relief.* Accordingly, I join only Parts I and III of the Court's opinion.