(a) Diesel fuel and special motor fuels

(1) Tax on diesel fuel and kerosene in certain cases

(A) In general

There is hereby imposed a tax on any liquid other than gasoline (as defined in section 4083)—

(i) sold by any person to an owner, lessee, or other operator of a diesel-powered highway vehicle or a diesel-powered train for use as a fuel in such vehicle or train, or

(ii) used by any person as a fuel in a diesel-powered highway vehicle or a diesel-powered train unless there was a taxable sale of such fuel under clause (i).

(B) Exemption for previously taxed fuel

No tax shall be imposed by this paragraph on the sale or use of any liquid if tax was imposed on such liquid under section 4081 (other than such tax at the Leaking Underground Storage Tank Trust Fund financing rate) and the tax thereon was not credited or refunded.

(C) Rate of tax

(i) In general

Except as otherwise provided in this subparagraph, the rate of the tax imposed by this paragraph shall be the rate of tax specified in section 4081(a)(2)(A) on diesel fuel which is in effect at the time of such sale or use.

(ii) Rate of tax on trains

In the case of any sale for use, or use, of diesel fuel in a train, the rate of tax imposed by this paragraph shall be—

(I) 3.3 cents per gallon after December 31, 2004, and before July 1, 2005,

(II) 2.3 cents per gallon after June 30, 2005, and before January 1, 2007, and

(III) 0 after December 31, 2006.

(iii) Rate of tax on certain buses

(I) In general

Except as provided in subclause (II), in the case of fuel sold for use or used in a use described in section 6427(b)(1) (after the application of section 6427(b)(3)), the rate of tax imposed by this paragraph shall be 7.3 cents per gallon (4.3 cents per gallon after September 30, 2028).

(II) School bus and intracity transportation

No tax shall be imposed by this paragraph on any sale for use, or use, described in subparagraph (B) or (C) of section 6427(b)(2).

(2) Alternative fuels

(A) In general

There is hereby imposed a tax on any liquid (other than gas oil, fuel oil, or any product taxable under section 4081 (other than such tax at the Leaking Underground Storage Tank Trust Fund financing rate))—

(i) sold by any person to an owner, lessee, or other operator of a motor vehicle or motorboat for use as a fuel in such motor vehicle or motorboat, or

(ii) used by any person as a fuel in a motor vehicle or motorboat unless there was a taxable sale of such liquid under clause (i).

(B) Rate of tax

The rate of the tax imposed by this paragraph shall be—

(i) except as otherwise provided in this subparagraph, the rate of tax specified in section 4081(a)(2)(A)(i) which is in effect at the time of such sale or use,

(ii) in the case of liquefied petroleum gas, 18.3 cents per energy equivalent of a gallon of gasoline,

(iii) in the case of any liquid fuel (other than ethanol and methanol) derived from coal (including peat) and liquid hydrocarbons derived from biomass (as defined in section 45K(c)(3)), 24.3 cents per gallon, and

(iv) in the case of liquefied natural gas, 24.3 cents per energy equivalent of a gallon of diesel.

(C) Energy equivalent of a gallon of gasoline

For purposes of this paragraph, the term “energy equivalent of a gallon of gasoline” means, with respect to a liquefied petroleum gas fuel, the amount of such fuel having a Btu content of 115,400 (lower heating value). For purposes of the preceding sentence, a Btu content of 115,400 (lower heating value) is equal to 5.75 pounds of liquefied petroleum gas.

(D) Energy equivalent of a gallon of diesel

For purposes of this paragraph, the term “energy equivalent of a gallon of diesel” means, with respect to a liquefied natural gas fuel, the amount of such fuel having a Btu content of 128,700 (lower heating value). For purposes of the preceding sentence, a Btu content of 128,700 (lower heating value) is equal to 6.06 pounds of liquefied natural gas.

(3) Compressed natural gas

(A) In general

There is hereby imposed a tax on compressed natural gas—

(i) sold by any person to an owner, lessee, or other operator of a motor vehicle or motorboat for use as a fuel in such motor vehicle or motorboat, or

(ii) used by any person as a fuel in a motor vehicle or motorboat unless there was a taxable sale of such gas under clause (i).

The rate of the tax imposed by this paragraph shall be 18.3 cents per energy equivalent of a gallon of gasoline.

(B) Bus uses

No tax shall be imposed by this paragraph on any sale for use, or use, described in subparagraph (B) or (C) of section 6427(b)(2) (relating to school bus and intracity transportation).

(C) Administrative provisions

For purposes of applying this title with respect to the taxes imposed by this subsection, references to any liquid subject to tax under this subsection shall be treated as including references to compressed natural gas subject to tax under this paragraph, and references to gallons shall be treated as including references to energy equivalent of a gallon of gasoline with respect to such gas.

(D) Energy equivalent of a gallon of gasoline

For purposes of this paragraph, the term “energy equivalent of a gallon of gasoline” means 5.66 pounds of compressed natural gas.

(b) Exemption for off-highway business use; reduction in tax for qualified methanol and ethanol fuel

(1) Exemption for off-highway business use

(A) In general

No tax shall be imposed by subsection (a) on liquids sold for use or used in an off-highway business use.

(B) Tax where other use

If a liquid on which no tax was imposed by reason of subparagraph (A) is used otherwise than in an off-highway business use, a tax shall be imposed by paragraph (1)(B), (2)(B), or (3)(A)(ii) of subsection (a) (whichever is appropriate) and by the corresponding provision of subsection (d)(1) (if any).

(C) Off-highway business use defined

For purposes of this subsection, the term “off-highway business use” has the meaning given to such term by section 6421(e)(2); except that such term shall not, for purposes of subsection (a)(1), include use in a diesel-powered train.

(2) Qualified methanol and ethanol fuel

(A) In general

In the case of any qualified methanol or ethanol fuel—

(i) the rate applicable under subsection (a)(2) shall be the applicable blender rate per gallon less than the otherwise applicable rate (6 cents per gallon in the case of a mixture none of the alcohol in which consists of ethanol), and

(ii) subsection (d)(1) shall be applied by substituting “0.05 cent” for “0.1 cent” with respect to the sales and uses to which clause (i) applies.

(B) Qualified methanol and ethanol fuel produced from coal

The term “qualified methanol or ethanol fuel” means any liquid at least 85 percent of which consists of methanol, ethanol, or other alcohol produced from coal (including peat).

(C) Applicable blender rate

For purposes of subparagraph (A)(i), the applicable blender rate is—

(i) except as provided in clause (ii), 5.4 cents, and

(ii) for sales or uses during calendar years 2001 through 2008, 1/10 of the blender amount applicable under section 40(h)(2) for the calendar year in which the sale or use occurs.

(D) Termination

On and after January 1, 2009, subparagraph (A) shall not apply.

(c) Certain liquids used as a fuel in aviation

(1) In general

There is hereby imposed a tax upon any liquid for use as a fuel other than aviation gasoline—

(A) sold by any person to an owner, lessee, or other operator of an aircraft for use in such aircraft, or

(B) used by any person in an aircraft unless there was a taxable sale of such fuel under subparagraph (A).

(2) Exemption for previously taxed fuel

No tax shall be imposed by this subsection on the sale or use of any liquid for use as a fuel other than aviation gasoline if tax was imposed on such liquid under section 4081 (other than such tax at the Leaking Underground Storage Tank Trust Fund financing rate) and the tax thereon was not credited or refunded.

(3) Rate of tax

The rate of tax imposed by this subsection shall be 21.8 cents per gallon (4.3 cents per gallon with respect to any sale or use for commercial aviation).

(d) Additional taxes to fund Leaking Underground Storage Tank Trust Fund

(1) Tax on sales and uses subject to tax under subsection (a)

In addition to the taxes imposed by subsection (a), there is hereby imposed a tax of 0.1 cent a gallon on the sale or use of any liquid (other than liquefied petroleum gas and other than liquefied natural gas) if tax is imposed by subsection (a)(1) or (2) on such sale or use. No tax shall be imposed under the preceding sentence on the sale or use of any liquid if tax was imposed with respect to such liquid under section 4081 at the Leaking Underground Storage Tank Trust Fund financing rate.

(2) Liquids used in aviation

In addition to the taxes imposed by subsection (c), there is hereby imposed a tax of 0.1 cent a gallon on any liquid (other than gasoline (as defined in section 4083))—

(A) sold by any person to an owner, lessee, or other operator of an aircraft for use as a fuel in such aircraft, or

(B) used by any person as a fuel in an aircraft unless there was a taxable sale of such liquid under subparagraph (A).

No tax shall be imposed by this paragraph on the sale or use of any liquid if there was a taxable sale of such liquid under section 4081.

(3) Diesel fuel used in trains

In the case of any sale for use or use after December 31, 2006, there is hereby imposed a tax of 0.1 cent per gallon on any liquid other than gasoline (as defined in section 4083)—

(A) sold by any person to an owner, lessee, or other operator of a diesel-powered train for use as a fuel in such train, or

(B) used by any person as a fuel in a diesel-powered train unless there was a taxable sale of such fuel under subparagraph (A).

No tax shall be imposed by this paragraph on the sale or use of any liquid if tax was imposed on such liquid under section 4081.

(4) Termination

The taxes imposed by this subsection shall not apply during any period during which the Leaking Underground Storage Tank Trust Fund financing rate under section 4081 does not apply.

(5) Nonapplication of exemptions other than for exports

For purposes of this section, the tax imposed under this subsection shall be determined without regard to subsections (b)(1)(A), (f), (g), (h), and (l). The preceding sentence shall not apply with respect to subsection (g)(3) and so much of subsection (g)(1) as relates to vessels (within the meaning of section 4221(d)(3)) employed in foreign trade or trade between the United States and any of its possessions.

[(e) Repealed. Pub. L. 108-357, title VIII, §853(d)(2)(C), Oct. 22, 2004, 118 Stat. 1613]

(f) Exemption for farm use

(1) Exemption

Under regulations prescribed by the Secretary, no tax shall be imposed under this section on any liquid sold for use or used on a farm for farming purposes.

(2) Use on a farm for farming purposes

For purposes of paragraph (1) of this subsection, use on a farm for farming purposes shall be determined in accordance with paragraphs (1), (2), and (3) of section 6420(c).

(g) Other exemptions

Under regulations prescribed by the Secretary, no tax shall be imposed under this section—

(1) on any liquid sold for use or used as supplies for vessels or aircraft (within the meaning of section 4221(d)(3));

(2) with respect to the sale of any liquid for the exclusive use of any State, any political subdivision of a State, or the District of Columbia, or with respect to the use by any of the foregoing of any liquid as a fuel;

(3) upon the sale of any liquid for export, or for shipment to a possession of the United States, and in due course so exported or shipped;

(4) with respect to the sale of any liquid to a nonprofit educational organization for its exclusive use, or with respect to the use by a nonprofit educational organization of any liquid as a fuel; and

(5) with respect to the sale of any liquid to a qualified blood collector organization (as defined in section 7701(a)(49)) for such organization’s exclusive use in the collection, storage, or transportation of blood.

For purposes of paragraph (4), the term “nonprofit educational organization” means an educational organization described in section 170(b)(1)(A)(ii) which is exempt from income tax under section 501(a). The term also includes a school operated as an activity of an organization described in section 501(c)(3) which is exempt from income tax under section 501(a), if such school normally maintains a regular faculty and curriculum and normally has a regularly enrolled body of pupils or students in attendance at the place where its educational activities are regularly carried on.

(h) Exemption for use by certain aircraft museums

(1) Exemption

Under regulations prescribed by the Secretary, no tax shall be imposed under this section on any liquid sold for use or used by an aircraft museum in an aircraft or vehicle owned by such museum and used exclusively for purposes set forth in paragraph (2)(C).

(2) Definition of aircraft museum

For purposes of this subsection, the term “aircraft museum” means an organization—

(A) described in section 501(c)(3) which is exempt from income tax under section 501(a),

(B) operated as a museum under charter by a State or the District of Columbia, and

(C) operated exclusively for the procurement, care, and exhibition of aircraft of the type used for combat or transport in World War II.

[(i) Repealed. Pub. L. 108-357, title VIII, §853(d)(2)(D), Oct. 22, 2004, 118 Stat. 1613]

(j) Sales by United States, etc.

The taxes imposed by this section shall apply with respect to liquids sold at retail by the United States, or by any agency or instrumentality of the United States, unless sales by such agency or instrumentality are by statute specifically exempted from such taxes.

[(k) Repealed. Pub. L. 108-357, title III, §301(c)(6), Oct. 22, 2004, 118 Stat. 1461]

(l) Exemption for certain uses

No tax shall be imposed under this section on any liquid sold for use in, or used in, a helicopter or a fixed-wing aircraft for purposes of providing transportation with respect to which the requirements of subsection (f) or (g) of section 4261 are met.

(m) Certain alcohol fuels

(1) In general

In the case of the sale or use of any partially exempt methanol or ethanol fuel the rate of the tax imposed by subsection (a)(2) shall be—

(A) after September 30, 1997, and before October 1, 2028—

(i) in the case of fuel none of the alcohol in which consists of ethanol, 9.15 cents per gallon, and

(ii) in any other case, 11.3 cents per gallon, and

(B) after September 30, 2028—

(i) in the case of fuel none of the alcohol in which consists of ethanol, 2.15 cents per gallon, and

(ii) in any other case, 4.3 cents per gallon.

(2) Partially exempt methanol or ethanol fuel

The term “partially exempt methanol or ethanol fuel” means any liquid at least 85 percent of which consists of methanol, ethanol, or other alcohol produced from natural gas.