Part A - Prohibitions

42 USC 8341 - Existing electric powerplants

(a) Certification by powerplants of coal capability 
At any time, the owner or operator of an existing electric powerplant may certify to the Secretary, for purposes of subsection (b) of this section
(1) whether or not such powerplant has or previously had the technical capability to use coal or another alternate fuel as a primary energy source;
(2) whether or not such powerplant could have the technical capability to use coal or another alternate fuel as a primary energy source without having
(A) substantial physical modification of the powerplant, or
(B) substantial reduction in the rated capacity of the powerplant; and
(3) whether or not it is financially feasible to use coal or another alternate fuel as a primary energy source in such a powerplant.
(b) Authority of Secretary to prohibit where coal or alternate fuel capability exists 
The Secretary may prohibit, in accordance with section 8343 (a) or (b) of this title, the use of petroleum or natural gas, or both, as a primary energy source in any existing electric powerplant, if an affirmative certification under subsection (a)(1), (2), and (3) of this section is in effect with respect to such powerplant and if, after examining the basis for the certification, the Secretary concurs with the certification.
(c) Authority of Secretary to prohibit excessive use in mixtures 
At any time, the owner or operator of an existing electric powerplant may certify to the Secretary for purposes of this subsection whether or not it is technically and financially feasible to use a mixture of petroleum or natural gas and coal or another alternate fuel as a primary energy source in that powerplant. If an affirmative certification under this subsection is in effect with respect to such powerplant and if, after examining the basis for the certification, the Secretary concurs with the certification, the Secretary may prohibit, in accordance with section 8343 (a) of this title, the use of petroleum or natural gas, or both, in such powerplant in amounts in excess of the minimum amount necessary to maintain reliability of operation of the unit consistent with maintaining reasonable fuel efficiency of such mixture.
(d) Amendment of subsection (a) and (c) certifications 
The owner or operator of any such powerplant may at any time amend any certification under subsection (a) or (c) of this section in order to take into account changes in relevant facts and circumstances; except that no such amendment to such a certification may be made after the date of any final prohibition under subsection (b) or (c) of this section based on that certification.

42 USC 8342 - Repealed. Pub. L. 10042, 1(a)(2), May 21, 1987, 101 Stat. 310

Section, Pub. L. 95–620, title III, § 302, Nov. 9, 1978, 92 Stat. 3306, authorized Secretary to prohibit use of petroleum or natural gas as primary energy source in existing major fuel-burning installations having coal or alternate fuel capability and, in installations in which mixtures of petroleum or natural gas and coal or other alternate fuels are found feasible, to prohibit excessive use of petroleum or natural gas in such mixtures.

42 USC 8343 - Rules relating to case-by-case and category prohibitions

(a) Case-by-case prohibitions 

(1) Except to the extent authorized by subsection (b) of this section, the Secretary shall prohibit any powerplant from using natural gas or petroleum under the authority granted him under section 8341 (b) or (c) of this title only by means of a final order issued by him which shall be limited to the particular powerplant involved.
(2) The Secretary may issue such a final order only with respect to a powerplant which is not, at the time the proposed order is issued, covered by a final rule issued under subsection (b) of this section.
(b) Prohibitions applicable to categories of facilities 

(1) The Secretary may prohibit, by rule, the use of natural gas or petroleum under section 8341 (b) of this title in existing electric powerplants.
(2) Each powerplant to be covered by any final rule issued under this subsection shall be specifically identified in the proposed rule published under section 8411 (b) of this title.
(3) In prescribing any final rule under this subsection, the Secretary shall take into account any special circumstances or characteristics of each category of powerplants (such as the intermittent use, size, age, or geographic location of such powerplants). Any such rules shall not apply in the case of any existing electric powerplant with respect to which a comparable prohibition was issued by order.