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CAA Section 112(d)-Emission Standards
Section 112(d) states that the EPA must promulgate regulations establishing emission standards (NESHAP) for each category or subcategory of major sources and area sources of HAPs [listed pursuant to Section 112(c)]. The standards must require the maximum degree of emission reduction that the EPA determines to be achievable by each particular source category. Different criteria for maximum achievable control technology (MACT) apply for new and existing sources. Less stringent standards, known as generally available control technology (GACT) standards, are allowed at the Administrator's discretion for area sources. The OAQPS contact for 112(d) is Yvonne W. Johnson (johnson.yvonnew@epa.gov).
See the Tables of final, proposed and upcoming regulations for current progress.
The full text of Section 112(d) is presented below:
(d) Emission standards.-
(1) In general.- The Administrator shall promulgate regulations
establishing emission standards for each category or subcategory
of major sources and area sources of hazardous air pollutants
listed for regulation pursuant to subsection (c) in accordance
with the schedules provided in subsections (c) and (e). The
Administrator may distinguish among classes, types, and sizes of
sources within a category or subcategory in establishing such
standards except that, there shall be no delay in the compliance
date for any standard applicable to any source under subsection
(i) as the result of the authority provided by this sentence.
(2) Standards and methods.- Emissions standards promulgated
under this subsection and applicable to new or existing sources
of hazardous air pollutants shall require the maximum degree of
reduction in emissions of the hazardous air pollutants subject to
this section (including a prohibition on such emissions, where
achievable) that the Administrator, taking into consideration the
cost of achieving such emission reduction, and any non-air
quality health and environmental impacts and energy requirements,
determines is achievable for new or existing sources in the
category or subcategory to which such emission standard applies,
through application of measures, processes, methods, systems or
techniques including, but not limited to, measures which -
(A) reduce the volume of, or eliminate emissions of, such
pollutants through process changes, substitution of materials
or other modifications,
(B) enclose systems or processes to eliminate emissions,
(C) collect, capture or treat such pollutants when released
from a process, stack, storage or fugitive emissions point,
(D) are design, equipment, work practice, or operational
standards (including requirements for operator training or
certification) as provided in subsection (h), or
(E) are a combination of the above.
None of the measures described in subparagraphs (A) through (D)
shall, consistent with the provisions of section 114(c), in any
way compromise any United States patent or United States
trademark right, or any confidential business information, or any
trade secret or any other intellectual property right.
(3) New and existing sources.- The maximum degree of reduction
in emissions that is deemed achievable for new sources in a
category or subcategory shall not be less stringent than the
emission control that is achieved in practice by the best
controlled similar source, as determined by the Administrator.
Emission standards promulgated under this subsection for existing
sources in a category or subcategory may be less stringent than
standards for new sources in the same category or subcategory but
shall not be less stringent, and may be more stringent than -
(A) the average emission limitation achieved by the best
performing 12 percent of the existing sources (for which the
Administrator has emissions information), excluding those
sources that have, within 18 months before the emission
standard is proposed or within 30 months before such standard
is promulgated, whichever is later, first achieved a level of
emission rate or emission reduction which complies, or would
comply if the source is not subject to such standard, with the
lowest achievable emission rate (as defined by section 171)
applicable to the source category and prevailing at the time,
in the category or subcategory for categories and subcategories
with 30 or more sources, or
(B) the average emission limitation achieved by the best
performing 5 sources (for which the Administrator has or could
reasonably obtain emissions information) in the category or
subcategory for categories or subcategories with fewer than 30
sources.
(4) Health threshold.- With respect to pollutants for which a
health threshold has been established, the Administrator may
consider such threshold level, with an ample margin of safety,
when establishing emission standards under this subsection.
(5) Alternative standard for area sources.- With respect only
to categories and subcategories of area sources listed pursuant
to subsection (c), the Administrator may, in lieu of the
authorities provided in paragraph (2) and subsection (f), elect
to promulgate standards or requirements applicable to sources in
such categories or subcategories which provide for the use of
generally available control technologies or management practices
by such sources to reduce emissions of hazardous air pollutants.
(6) Review and revision.- The Administrator shall review, and
revise as necessary (taking into account developments in practic-
es, processes, and control technologies), emission standards
promulgated under this section no less often than every 8 years.
(7) Other requirements preserved.- No emission standard or
other requirement promulgated under this section shall be
interpreted, construed or applied to diminish or replace the
requirements of a more stringent emission limitation or other
applicable requirement established pursuant to section 111, part
C or D, or other authority of this Act or a standard issued under
State authority.
(8) Coke Ovens.-
(A) Not later than December 31, 1992, the Administrator
shall promulgate regulations establishing emission standards
under paragraphs (2) and (3) of this subsection for coke
oven batteries. In establishing such standards, the
Administrator shall evaluate -
(i) the use of sodium silicate (or equivalent) luting
compounds to prevent door leaks, and other operating
practices and technologies for their effectiveness in
reducing coke oven emissions, and their suitability for
use on new and existing coke oven batteries, taking into
account costs and reasonable commercial door warranties;
and
(ii) as a basis for emission standards under this
subsection for new coke oven batteries that begin
construction after the date of proposal of such standards,
the Jewell design Thompson non-recovery coke oven
batteries and other non-recovery coke oven technologies,
and other appropriate emission control and coke production
technologies, as to their effectiveness in reducing coke
oven emissions and their capability for production of
steel quality coke.
Such regulations shall require at a minimum that coke oven
batteries will not exceed 8 per centum leaking doors, 1 per
centum leaking lids, 5 per centum leaking offtakes, and 16
seconds visible emissions per charge, with no exclusion for
emissions during the period after the closing of self-sealing
oven doors. Notwithstanding subsection (i), the compliance date
for such emission standards for existing coke oven batteries
shall be December 31, 1995.
(B) The Administrator shall promulgate work practice
regulations under this subsection for coke oven batteries
requiring, as appropriate -
(i) the use of sodium silicate (or equivalent) luting
compounds, if the Administrator determines that use of
sodium silicate is an effective means of emissions control
and is achievable, taking into account costs and
reasonable commercial warranties for doors and related
equipment; and
(ii) door and jam cleaning practices.
Notwithstanding subsection (i), the compliance date for
such work practice regulations for coke oven batteries
shall be not later than the date 3 years after the date of
enactment of the Clean Air Act Amendments of 1990.
(C) For coke oven batteries electing to qualify for an
extension of the compliance date for standards promulgated
under subsection (f) in accordance with subsection (i)(8),
the emission standards under this subsection for coke oven
batteries shall require that coke oven batteries not
exceed 8 per centum leaking doors, 1 per centum leaking
lids, 5 per centum leaking offtakes, and 16 seconds
visible emissions per charge, with no exclusion for
emissions during the period after the closing of
self-sealing doors. Notwithstanding subsection (i), the
compliance date for such emission standards for existing
coke oven batteries seeking an extension shall be not
later than the date 3 years after the date of enactment of
the Clean Air Act Amendments of 1990.
(9) Sources licensed by the nuclear regulatory commission.-
No standard for radionuclide emissions from any category or
subcategory of facilities licensed by the Nuclear Regulatory
Commission (or an Agreement State) is required to be
promulgated under this section if the Administrator determines,
by rule, and after consultation with the Nuclear Regulatory
Commission, that the regulatory program established by the
Nuclear Regulatory Commission pursuant to the Atomic Energy Act
for such category
or subcategory provides an ample margin of safety to protect
the public health. Nothing in this subsection shall preclude or
deny the right of any State or political subdivision thereof to
adopt or enforce any standard or limitation respecting
emissions of radionuclides which is more stringent than the
standard or limitation in effect under section 111 or this
section.
(10) Effective date.- Emission standards or other
regulations promulgated under this subsection shall be
effective upon promulgation.