This interlocutory appeal requires us to determine whether the United States has waived its sovereign immunity for actions for civil damages under the Resource Conservation and Recovery Act, 42 U.S.C. § 6901 et seq., and the Clean Water Act, 33 U.S.C. § 1251 et seq. We affirm the district court’s decision that sovereign immunity was waived under both statutes.
The United States Department of Energy owns a 1,050 acre uranium processing plant in Fernald, Ohio that is operated under a management contract by private contractors. The Fernald facility processes uranium for the production of nuclear weapons. The Fernald facility does not have a nuclear reactor, but processes performed there generate both radioactive and non-radioactive hazardous wastes.
In March 1986, the State of Ohio filed this action against the Department of Energy, the Secretary of the Department of Energy, and its private contractors, seeking civil penalties and other relief. The State of Ohio alleges that the defendants improperly disposed of hazardous wastes, released radioactive materials into the environment, and polluted surface and ground water. The State of Ohio grounds its claims primarily in the Comprehensive Environmental Response, Compensation and Liability Act of 1980, 42 U.S.C. § 9601 et seq., the Resource Conservation and Recovery Act, 42 U.S.C. § 6901 et seq., the Clean Water Act, 33 U.S.C. § 1251 et seq., the Ohio Solid & Hazardous Waste Control Act, Ohio Rev.Code § 3734, and the Ohio Water Pollution Control Act, Ohio Rev. Code § 6111.
The Department of Energy moved to dismiss the claims for civil penalties as barred by sovereign immunity. The district court denied this motion, holding that sovereign immunity was waived under the Resource Conservation and Recovery Act and the Clean Water Act. The district court certified its decision for immediate appeal because the decision involves a controlling question of law and immediate appeal may advance the ultimate resolution of the litigation. 28 U.S.C. § 1292(b). We exercised our discretion to hear this interlocutory appeal on whether sovereign immunity was waived. Id.
A waiver of sovereign immunity must be clear, express, and unambiguous; it cannot be implied from vague language. Block v. North Dakota, 461 U.S. 273, 280, 103 S.Ct. 1811, 1816, 75 L.Ed.2d 840 (1983); Hancock v. Train, 426 U.S. 167, 187, 96 S.Ct. 2006, 2016, 48 L.Ed.2d 555 (1976) (applied to environmental law). In determining whether a waiver is clear, the controlling factor is the “underlying congressional policy.” Franchise Tax Bd. v. U.S. Postal *1060Service, 467 U.S. 512, 521, 104 S.Ct. 2549, 2554, 81 L.Ed.2d 446 (1984). We must avoid the temptation to seek any hint of ambiguity that can be used to twist the statute into denying sovereign immunity. See id. When Congress enacts a clear waiver, that waiver should not be “thwarted by an unduly restrictive interpretation” in the courts. Canadian Aviator v. United States, 324 U.S. 215, 65 S.Ct. 639, 89 L.Ed. 901 (1945).
I. The Clean Water Act
We first address whether Congress waived sovereign immunity in the Clean Water Act, 33 U.S.C. § 1323, for claims brought by the State of Ohio under the Clean Water Act and Ohio Water Pollution law. Section 1323 states:
(a) Each department, agency, or instrumentality of the executive, legislative, and judicial branches of the Federal Government (1) having jurisdiction over any property or facility, or (2) engaged in any activity resulting, or which may result, in the discharge or runoff of pollutants and each officer, agent, or employee thereof in the performance of his official duties, shall be subject to, and comply with, all Federal, State, interstate, and local requirements, administrative authority, and process and sanctions respecting the control and abatement of water pollution in the same manner, and to the same extent as any nongovernmental entity including the payment of reasonable service charges. The preceding sentence shall apply (A) to any requirement whether substantive or procedural (including any recordkeeping permits and any other requirement, whatsoever), (B) to the exercise of any Federal, State, or local administrative authority, and (C) to any process and sanction, whether enforced in Federal, State, or local courts or in any other manner. This subsection shall apply notwithstanding any immunity of such agencies, officers, agents, or employees under any law or rule of law....
No officer, agent, or employee of the United States shall be personally liable for any civil penalty arising from the performance of his official duties, for which he is not otherwise liable, and the United States shall be liable only for those civil penalties arising under Federal law or imposed by a State or local court to enforce an order or the process of such court....
33 U.S.C. § 1323 (emphasis added). This statutory language should be interpreted according to its ordinary usage. See Ernst & Ernst v. Hochfelder, 425 U.S. 185, 199 n. 20, 96 S.Ct. 1375, 1384 n. 20, 47 L.Ed.2d 668 (1976). The first sentence of section 1323 subjects the Department of Energy to “any requirement,” including “sanctions,” to the same extent as a private entity under the Act. Subsection C specifically states that sovereign immunity is waived for any sanction. Any reader would interpret this statement to subject the Department of Energy to civil penalties. In addition, the Oxford English Dictionary defines “sanction” as “[t]he specific penalty enacted in order to enforce obedience to the law.” The Compact Edition of the Oxford English Dictionary 2633 (1971) (emphasis added). See Hochfelder, 425 U.S., at 199 n. 20, 96 S.Ct. at 1384 n. 20 (a dictionary may show ordinary usage). According to its ordinary usage, the language of the waiver of sovereign immunity in section 1323 clearly includes civil penalties.
Congress’s 1977 amendment to the Clean Water Act further evidences its intent to waive federal sovereign immunity to civil penalties. Section 1323 was amended in the aftermath of EPA v. Cal. ex rel. State Water Resources Control Bd., 426 U.S. 200, 96 S.Ct. 2022, 48 L.Ed.2d 578 (1976), in which the Court interpreted an earlier version of section 1323. That earlier version of section 1323 subjected federal agencies to “Federal, State, interstate, and local requirements ... to the same extent as any person is subject to such requirements.” 33 U.S.C. § 1323 (1970). The Court distinguished between substantive and procedural requirements and held that Congress had not waived sovereign immunity for procedural requirements, including all en-*1061foreement mechanisms.1 The Court held that section 1323 merely subjected federal facilities to the substantive pollution limits in state laws. Following that decision, Congress amended the Clean Water Act, stating that federal facilities were subject to “all” requirements, including “process and sanctions.” The amendment clearly subjects federal agencies to civil penalties. The fact that the amendment was provoked by a Supreme Court decision protecting sovereign immunity underscores Congress’s determination to waive sovereign immunity for civil penalties.
If Congress’s amendment of the Clean Water Act did not waive sovereign immunity for civil penalties, it would be impossible to give meaning to each part of section 1323. The Supreme Court has stated, “It is axiomatic that all parts of an Act ‘if at all possible, are to be given effect.’ ” F.A.A. Administrator v. Robertson, 422 U.S. 255, 261, 95 S.Ct. 2140, 2145, 45 L.Ed.2d 164 (1975), quoting Weinberger v. Hynson, Wescott & Dunning, 412 U.S. 609, 633, 93 S.Ct. 2469, 2485, 37 L.Ed.2d 207 (1973) (citations omitted). Section 1323 explicitly limits its waiver of sovereign immunity for civil penalties to those “arising under federal law.” This limit would become superfluous if section 1323 were interpreted as not waiving sovereign immunity for civil penalties at all.
In order for the claims brought by the State of Ohio to fall within the waiver of sovereign immunity, those claims must arise under federal law. See 33 U.S.C. § 1323. Claims brought under the Clean Water Act itself, such as the claims under 33 U.S.C. § 1365, clearly arise under federal law.
The claims brought under the Ohio water pollution laws also arise under federal law because of the legislative scheme of the Clean Water Act. See Ohio Rev.Code § 6111.09. The Clean Water Act mandates that the states may create their own water pollution laws, which may qualify to replace the requirements of the Clean Water Act. 33 U.S.C. § 1342(b). Upon implementing a state permit program “in accordance with” 33 U.S.C. § 1342, the state assumes responsibility for pollution permits on behalf of and instead of the Environmental Protection Agency. 33 U.S.C. § 1342(c). The Environmental Protection Agency is charged with promulgating the standards that state programs must meet to obtain approval. 33 U.S.C. § 1342; see 40 C.F.R. § 123 (regulations setting forth the requirements for state programs to be approved). In order to be approved, a state law must provide for civil penalties. 33 U.S.C. § 1342(b)(7); 40 C.F.R. § 123.27(a)(3). Once a state water pollution law is approved, compliance with the state law is compliance with the Clean Water Act. 33 U.S.C. § 1342(k). Thus, under the terms of the Clean Water Act, a qualifying state water pollution law, including its civil penalties, arises under federal law.
Other sections of the Clean Water Act emphasize Congress’s intent that claims under state pollution laws may arise under federal law. The introductory section of the Clean Water Act states, “It is the policy of Congress that the States ... implement the policy programs under sections 402 and 404 of this Act.” 33 U.S.C. § 1251(b) (emphasis added). Congress continually uses language such as “permit issued under Section 402 of this Act ... by a State.” 33 U.S.C. § 1319(a) (emphasis added); see 33 U.S.C. §§ 1319(c), 1319(d), 1311(i). Further, the Clean Water Act empowers the Environmental Protection Agency to enforce state permits as federal requirements. 33 U.S.C. § 1319(a). Thus, practically speaking, actions under a qualifying state water pollution law arise under federal law.
The Ohio water pollution law, codified at Ohio Rev.Code § 6111, arises under federal law because it is an approved state water pollution law. It is uncontroverted that the *1062Ohio Water Pollution Act meets the requirements of the Clean Water Act. Indeed, as authorized by Congress, the Environmental Protection Agency has suspended its issuance of permits in Ohio in favor of the state’s issuance of permits under the Ohio Water Pollution Act pursuant to 33 U.S.C. § 1342(c)(1). The Ohio Act specifically requires the Director of the Ohio Environmental Protection Agency to manage the Ohio pollution permit program in compliance with the Clean Water Act. The Ohio Act also bars the Director from issuing a permit to which the federal Environmental Protection Agency objects. Ohio Rev.Code § 6111.03(J)(3). The limitation of the waiver of sovereign immunity to civil penalties arising under federal law is aimed at state water pollution laws that fail to meet approval under the Clean Water Act; it is not aimed at approved laws such as Ohio Rev. Code § 6111.
Congress clearly has waived sovereign immunity for civil penalties of federal agencies that violate the Clean Water Act and the Ohio Water Pollution Act. Thus, we need not consider the State of Ohio’s alternative argument that the citizen suit provision of the Clean Water Act, 33 U.S.C. § 1365, authorizes civil penalties against federal facilities.
II. The Resource Conservation and Recovery Act
The Department of Energy also appeals the district court’s determination that the general waiver provision of the Resource Conservation and Recovery Act, 42 U.S.C. § 6961, waives sovereign immunity in regard to civil penalties. The State of Ohio responds that the district court correctly decided this question and, in the alternative, contends that sovereign immunity has been waived under the citizen suit provision of the Resource Conservation and Recovery Act, 42 U.S.C. § 6972. We hold that Congress did not waive sovereign immunity for civil penalties under the general waiver, but that Congress did waive sovereign immunity for civil penalties under the citizen suit provision.
A. General Waiver
Congress has at least waived the immunity of the United States in 42 U.S.C. § 6961, which states:
Each department, agency, and instrumentality of the executive, legislative, and judicial branches of the Federal Government (1) having jurisdiction over any solid waste management facility or disposal site, or (2) engaged in any activity resulting, or which may result, in the disposal or management of solid waste or hazardous waste shall be subject to, and comply with, all Federal, State, interstate, and local requirements, both substantive and procedural (including any requirement for permits or reporting or any provisions for injunctive relief and such sanctions as may be imposed by a court to enforce such relief), respecting control and abatement of solid waste or hazardous waste disposal in the same manner, and to the same extent, as any person is subject to such requirements, including the payment of reasonable service charges. Neither the United States, nor any agent, employee, or officer thereof, shall be immune or exempt from any process or sanction of any State or Federal Court, with respect to the enforcement of any such injunctive relief
42 U.S.C. § 6961 (emphasis added). This section renders the federal government subject to the “requirements” of federal, state and local laws. The issue is whether “requirements” includes civil penalties in an action brought by a state. Despite indications that Congress intended to waive sovereign immunity for civil penalties here, we find that any such waiver is not stated clearly enough to be recognized. See Block v. North Dakota, 461 U.S. 273, 280, 103 S.Ct. 1811, 1816, 75 L.Ed.2d 840 (1983).
An ordinary reading of the phrase, “all ... requirements,” indicates that a civil penalty is a “requirement” because a party violating the statute will be required to pay the penalty. Circumstances surrounding the passage of the Resource Conservation and Recovery Act also support a finding that “requirements” include civil penalties. *1063Congress enacted the Resource Conservation and Recovery Act a few months after the Supreme Court decisions in Hancock v. Train, 426 U.S. 167, 96 S.Ct. 2006, 48 L.Ed.2d 555 (1976), and EPA v. Cal. ex rel. State Water Resources Control Bd., 426 U.S. 200, 96 S.Ct. 2022, 48 L.Ed.2d 578 (1976). These decisions held that Congress did not waive sovereign immunity for procedural requirements, including enforcement mechanisms, in its previously enacted environmental statutes. The Court explicitly based its holding on the fact that the statutory waivers said “requirements” rather than “all requirements.” Hancock, 426 U.S. at 182, 96 S.Ct. at 2014; State Water Resources Control Bd., 426 U.S. at 214, 96 S.Ct. at 2029 (stating that its reasoning in Hancock controls sovereign immunity questions arising under the Clean Water Act as well). In the Resource Conservation and Recovery Act, Congress used the specific language, “all requirements,” that the Court reasoned to be adequate to subject the federal government to enforcement mechanisms of state statutes. Thus, Congress may have intended to waive sovereign immunity for civil penalties.
Despite these considerations, we decline to find a waiver of immunity for civil penalties under section 6961 because of two complications. The first complication is the difference between the language in section 6961 and the waiver provision in the Clean Water Act, 33 U.S.C. § 1323. The Clean Water Act provides that federal facilities are subject to both “all requirements” and “sanctions” of federal and state law. 33 U.S.C. § 1321. If “all requirements” includes sanctions, then the discussion of sanctions would be superfluous. In addition, the waiver provision in the Clean Water Act expressly limits the waiver of sovereign immunity to “those civil penalties arising under Federal law.” Id. As we have already noted, this limit protects the United States from civil penalties under the state water pollution laws that do not have federal approval. Like the Clean Water Act, the Resource Conservation and Recovery Act is an umbrella act for state pollution laws, but, unlike the Clean Water Act, it lacks language to protect the United States from suits under unapproved state laws. Although Congress may have intended to waive sovereign immunity in the Resource Conservation Act, the differences between the Resource Conservation Act and the Clean Water Act make any waiver less than clear.
Second, section 6961 explicitly discusses injunctive relief twice, but never mentions monetary relief or civil penalties. The last statement of section 6961 specifically waives sovereign immunity for injunctive relief and sanctions to enforce injunctive relief. Also, the parenthetical in section 6961, which lists requirements to which the United States may be subjected, specifically discusses injunctive relief, but it does not mention monetary relief. The list in this parenthetical begins with “including” and we interpret it to be a suggestive rather than exhaustive list. See P.C. Pfeiffer Co. v. Ford, 444 U.S. 69, 77 n. 7, 100 S.Ct. 328, 334 n. 7, 62 L.Ed.2d 225 (1979). Yet the specific mention of injunctive sanctions appears to omit civil penalties too neatly to be an accident. It may be that monetary relief and civil penalties are included in “requirements,” as suggested above, but such an interpretation would rest on ambiguous evidence.
In order for us to recognize a Congressional waiver of sovereign immunity, the waiver must be clear-cut. Block v. North Dakota, 461 U.S. 273, 280, 103 S.Ct. 1811, 1816, 75 L.Ed.2d 840 (1983); Hancock v. Train, 426 U.S. 167, 187, 96 S.Ct. 2006, 2016, 48 L.Ed.2d 555 (1976). We find no such clear waiver here. The Ninth Circuit has found a different plausible reading of section 6961 by distinguishing between requirements and enforcement mechanisms. People v. Walters, 751 F.2d 977, 978 (9th Cir.1984) (per curiam) (holding that sovereign immunity was not waived to allow state criminal sanctions because such sanctions are enforcement devices). In United States v. State of Washington, 872 F.2d 874 (9th Cir.1989), the Ninth Circuit held that the Resource Conservation and Recovery Act did not waive sovereign immunity for civil penalties because such penalties were enforcement mechanisms. Like the *1064Ninth Circuit, we fail to find a clear waiver of sovereign immunity for civil penalties in section 6961.
B. Citizen Suit Provision
Congress clearly waived sovereign immunity for civil penalties in the citizen suit provision of the Resource Conservation and Recovery Act, 42 U.S.C. § 6972.2 Section 6972 states in relevant part:
(a) Except as provided in subsection (b) or (c) of this section, any person may commence a civil action on his own behalf—
(1)(A) against any person (including (a) the United States, and (b) any other governmental instrumentality or agency, to the extent permitted by the eleventh amendment to the Constitution) who is alleged to be in violation of any permit, standard, regulation, condition, requirement, prohibition, or order which has become effective pursuant to this chapter; or
(B) against any person, including the United States and any other governmental instrumentality or agency, to the extent permitted by the eleventh amendment to the Constitution, and including any past or present generator, past or present transporter, or past or present owner or operator of a treatment, storage, or disposal facility, who has contributed or who is contributing to the past or present handling, storage, treatment, transportation, or disposal of any solid or hazardous waste which may present an imminent and substantial endangerment to health or the environment; or
(2) against the Administrator where there is alleged a failure of the Administrator to perform any act or duty under this chapter which is not discretionary with the Administrator.
... The district court shall have jurisdiction, without regard to the amount in controversy or the citizenship of the parties, to enforce the permit, standard, regulation, condition, requirement, prohibition, or order, referred to in paragraph (l)(a), to restrain any person who has contributed or who is contributing to the past or present handling, storage, treatment, transportation, or disposal of any solid or hazardous waste referred to in paragraph (l)(b), to order such person to take such other action as may be necessary, or both, or to order the Administrator to perform the act or duty referred to in paragraph (2), as the case may be, and to apply any appropriate civil penalties under section 6928(a) and (g) of this title.
Id. (emphasis added). The State of Ohio may bring its action under the citizen’s suit provision because the definition of “person” includes states under the Resource Conservation and Recovery Act. 42 U.S.C. § 6903(15). The citizen’s suit provision explicitly allows the action to be brought against the United States or a federal instrumentality, agency, or administrator. In bringing the action, the State of Ohio may seek civil penalties under 42 U.S.C. §§ 6928(a), 6928(g).
The Department of Energy argues that the United States is not included in the scope of the civil penalties allowed under the citizen’s suit provision. Civil penalties are included in section 6972 by reference to another section of the Resource Conservation and Recovery Act, 42 U.S.C. § 6928, but the United States is included in the definition of a “person” only under section 6972. Compare 42 U.S.C. § 6972(a)(1) (specifically including the United States as a “person”) with 42 U.S.C. § 6903(15) (United States not included in general definition of “person”). In order to find that Congress clearly waived sovereign immunity for civil penalties, we must find that Congress clearly intended that its specific inclusion of the United States for citizen suits would extend to the application of civil penalties.
The fairest reading of section 6972 includes the United States in the application *1065of civil penalties. Section 6972 incorporates the civil penalty sections, not vice versa. Thus, the definition of "person” within section 6972 applies, not the general definition in 42 U.S.C. § 6903(15). This definition of “person” within section 6972 includes the United States. In addition, the legislative history demonstrates that Congress intended to subject the United States to civil penalties in citizen suits. The Senate Committee stated:
Either a noncomplying agency [or] the Administrator, if he fails to act, are subject to the citizen suit and penalty provisions of section 7002. To assure that there is no confusion as to this, the amendments to section 7002 continue to use the current statutory language to specifically authorize a suit against “any person, including the United States.... ”
S.Rep. No. 284, 98th Cong., 1st Sess. 44 (1983). Although this discussion concerns the requirements for federal facilities to submit an inventory of hazardous waste sites to the Environmental Protection Agency, this statement shows the Senate’s intent that civil penalties would be available in a citizen’s suit against the United States.
Congress’s waiver of sovereign immunity for civil penalties accords with the underlying congressional policy of the Resource Conservation and Recovery Act to eliminate the unsafe disposal of hazardous wastes. H.R.Rep. No. 1491, 94th Cong., 2d Sess. 3 (1976), reprinted in 1976 U.S.Code Cong. & Admin.News 6238, 6241; see Franchise Tax Bd. of Cal. v. U.S. Postal Service, 467 U.S. 512, 521, 104 S.Ct. 2549, 2554, 81 L.Ed.2d 446 (1984). Congress expressed great concern for hazardous waste disposal at federal facilities because the federal government owned over 20,000 such facilities. H.R.Rep. No. 1491 at 46, reprinted in 1976 U.S.Code Cong. & Admin.News at 6284. Far from protecting federal facilities from failure to comply with hazardous waste pollution laws, Congress demanded that federal facilities “provide national leadership in dealing with solid waste and hazardous waste disposal systems.” S.Rep. No. 988, 94th Cong., 2d Sess., 24 (1976). In light of these broad goals, the clear interpretation of Congress’s later addition of civil penalties is that Congress intended to apply those penalties to federal facilities as well as private entities, consistent with the other aspects of the citizen suit provision.
We find that Congress has waived sovereign immunity for civil penalties under both the Clean Water Act and the Resource Conservation and Recovery Act. Therefore, the judgment of the district court is affirmed.
. Although State Water Resources Control Bd. and its companion case, Hancock v. Train, 426 U.S. 167, 96 S.Ct. 2006, 48 L.Ed.2d 555 (1976), concerned injunctive relief, the Court discussed the issues in terms of enforcement mechanisms. The Court did not distinguish between injunc-tive relief and civil penalties or damages because it viewed both as procedural requirements, not covered by its interpretation of the pollution acts.
. The Ninth Circuit did not address this issue in either Walters, 751 F.2d 977, or Washington, 872 F.2d 874.