Current through Register Vol. 50, No. 9, September 20, 2024
This regulation applies to all stacks in existence and all
dispersion techniques implemented since December 31, 1970.
A. Definitions. For the purpose of this
Section, the terms below will have the meaning herein given.
Dispersion Technique- any technique which
attempts to affect the concentration of a pollutant in the ambient air
by:
1. using that portion of a stack
which exceeds good engineering practice stack height;
2. varying the rate of emission of a
pollutant according to atmospheric conditions or ambient concentrations of that
pollutant; or
3. increasing final
exhaust gas plume rise by manipulating source process parameters, exhaust gas
parameters, stack parameters or combining exhaust gases from several existing
stacks into one stack; or other selective handling of exhaust gas streams so as
to increase the exhaust gas plume rise. LAC 33:III.921.A.
Dispersion
Technique.3 does not include:
a. the
reheating of a gas stream, following use of a pollution control system, for the
purpose of returning the gas to the temperature at which it was originally
discharged from the facility generating the gas stream;
b. the merging of exhaust gas streams where:
i. the source owner or operator demonstrates
that the facility was originally designed and constructed with such merged gas
streams;
ii. after July 8, 1985,
such merging is part of a change in operation at the facility that includes the
installation of pollution controls and is accompanied by a net reduction in the
allowable emissions of a pollutant. This exclusion from the definition of
dispersion techniques shall apply only to the emission
limitation for the pollutant affected by such change in operation; or
iii. before July 8, 1985, such merging was
part of a change in operation at the facility that included the installation of
emissions control equipment or was carried out for sound economic or
engineering reasons. Where there was an increase in the emission limitation or,
in the event that no emission limitation was in existence prior to the merging,
an increase in the quantity of pollutants actually emitted prior to the
merging, the administrative authority shall presume that merging was
significantly motivated by an intent to gain emissions credit for greater
dispersion. Absent a demonstration by the source owner or operator that merging
was not significantly motivated by such intent, the administrative authority
shall deny credit for the effects of such merging in calculating the allowable
emissions for the source;
c. smoke management in agricultural or
silvicultural prescribed burning programs;
d. episodic restrictions on residential
woodburning and open burning; or
e.
techniques under LAC 33:III.921.A.Dispersion Technique.3,
which increase final exhaust gas plume rise where the resulting allowable
emissions of sulfur dioxide from the facility do not exceed 5,000 tons per
year.
Emission Limitation and Emission Standard-
a requirement established by the administrative authority or administrator
which limits the quantity, rate, or concentration of emissions of air
pollutants on a continuous basis, including any requirements which limit the
level of opacity, prescribe equipment, set fuel specifications, prescribe
operation or maintenance procedures for a source to assure continuous emission
reduction.
Excessive Concentrations- is defined for
the purpose of determining good engineering practice stack height under LAC
33:III.921.A.Good Engineering Practice (GEP) Stack Height.3
and means:
1. for sources seeking
credit for stack height exceeding that established under LAC
33:III.921.A.Good Engineering Practice (GEP) Stack Height.2, a
maximum ground-level concentration due to emissions from a stack due in whole
or part to downwash, wakes, and eddy effects produced by nearby structures or
nearby terrain features which individually is at least 40 percent in excess of
the maximum concentration experienced in the absence of such downwash, wakes,
or eddy effects and which contributes to a total concentration due to emissions
from all sources that is greater than an ambient air quality standard. For
sources subject to the prevention of significant deterioration program (PSD),
an excessive concentration alternatively means a maximum ground-level
concentration due to emissions from a stack due in whole or part to downwash,
wakes, or eddy effects produced by nearby structures or nearby terrain features
which individually is at least 40 percent in excess of the maximum
concentration experienced in the absence of such downwash, wakes, or eddy
effects and a greater than a prevention of significant deterioration increment.
The allowable emission rate to be used in making demonstrations under this
Section shall be prescribed by the new source performance standard that is
applicable to the source category unless the owner or operator demonstrates
that this emission rate is infeasible. Where such demonstrations are approved
by the administrative authority, an alternative emission rate shall be
established in consultation with the source owner or operator.
2. for sources seeking credit after October
11, 1983, for increases in existing stack heights up to the heights established
under LAC 33:III.921.A.
Good Engineering Practice (GEP) Stack
Height.2, either:
a. a maximum
ground-level concentration due in whole or part to downwash, wakes, or eddy
effects as provided in Paragraph 1 above, except that the emission rate
specified by these regulations (or in the absence of such a limit, the actual
emission rate) shall be used; or
b.
the actual presence of a local nuisance caused by the existing stack, as
determined by the administrative authority;
3. for sources seeking credit after January
12, 1979 for a stack height determined under LAC 33:III.921.A.
Good
Engineering Practice (GEP) Stack Height.2 where the administrative
authority requires the use of a field study or fluid model to verify GEP stack
height, for sources seeking stack height credit after November 9, 1984 based on
the aerodynamic influence of cooling towers, and for sources seeking stack
height credit after December 31, 1970 based on the aerodynamic influence of
structures not adequately represented by the equations in LAC
33:III.921.A.
Good Engineering Practice (GEP) Stack Height.2, a
maximum ground-level concentration due in whole or part to downwash, wakes, or
eddy effects that is at least 40 percent in excess of the maximum concentration
experienced in the absence of such downwash, wakes, or eddy effects.
Good Engineering Practice (GEP) Stack
Height- the greater of:
1. 65 meters, measured from the ground-level
elevation at the base of the stack;
2.
a.
i. for stacks in existence on January 12,
1979, and for which the owner or operator had obtained all applicable permits
or approvals required under state or federal regulations:
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ii. provided
the owner or operator produces evidence that this equation was actually relied
on in establishing an emission limitation;
b.
i. for
all other stacks:
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where:
Hg = good engineering practice stack height, measured from
the ground-level elevation of the base of the stack;
H = height of nearby structure(s) measured from the
ground-level elevation at the base of the stack;
L = lesser dimension, height or projected width, of nearby
structure(s);
ii. provided
that EPA or the administrative authority may require the use of a field study
or fluid model to verify GEP stack height for the source;
or
3. the
height demonstrated by a fluid model or a field study approved by EPA or the
administrative authority, which ensures that the emissions from a stack do not
result in excessive concentrations of any air pollutant as a result of
atmospheric downwash, wakes, or eddy effects created by the source itself,
nearby structures, or nearby terrain features.
Nearby- as used in LAC
33:III.921.A.Good Engineering Practice (GEP) Stack Height of
this Section is defined for a specific structure or terrain feature
and:
1. for purposes of
applying the formulae provided in LAC 33:III.921.A.Good Engineering
Practice (GEP) Stack Height.2 means that distance up to five times the
lesser of the height or the width dimension of a structure, but not greater
than 0.8 km (1/2 mile); and
2. for
conducting the demonstrations under LAC 33:III.921.A.Good Engineering
Practice (GEP) Stack Height.3 means not greater than 0.8 km (1/2
mile), except that the portion of a terrain feature may be considered to be
nearby which falls within a distance of up to 10 times the maximum height
(Ht) of the feature, not to exceed 2 miles if such
feature achieves a height (Ht) 0.8 km from the stack
that is at least 40 percent of the GEP stack height determined by the formulae
provided in LAC 33:III.921.A.Good Engineering Practice (GEP) Stack
Height.2.b or 26 meters, whichever is greater, as measured from the
ground-level elevation at the base of the stack. The height of the structure or
terrain feature is measured from the ground-level elevation at the base of the
stack.
Stack- any point in a source designed to
emit solids, liquids, or gases into the air, including a pipe or duct but not
including flares.
Stack in Existence- the owner or operator
had:
1. begun, or caused to begin, a
continuous program of physical on-site construction of the stack; or
2. entered into binding agreements or
contractual obligations, which could not be cancelled or modified without
substantial loss to the owner or operator, to undertake a program of
construction of the stack to be completed in a reasonable time.
B. Degree of Emission
Limitation
1. The degree of emission
limitation required of any source for control of any air pollutant must not be
affected by so much of any source's stack height that exceeds good engineering
practice (GEP) or by any other dispersion technique, except as provided herein.
The administrative authority will notify the public of the availability of any
stack height demonstration study and will provide opportunity for public
hearing on it. This Section does not restrict, in any manner, the actual stack
height of any source.
2. The
provisions of LAC 33:III.921.B shall not apply to:
a. stack heights in existence, or dispersion
techniques implemented prior to December 31, 1970, except where pollutants are
being emitted from such stacks or using such dispersion techniques by sources,
as defined in
Section
111(a)(3) of
the Clean Air Act, which were constructed or reconstructed, or for which major
modifications, as defined in LAC 33:III.509.B.Major
Modification, were carried out after December 31, 1970; or
b. coal-fired steam electric generating
units, subject to the provisions of Section 118 of the Clean Air Act, which
commenced operation before July 1, 1957, and whose stacks were constructed
under a construction contract awarded before February 8, 1974.
C. Review of New Sources
and Modifications. The degree of emission limitation required of any source for
control of any air pollutant must not be affected so much by any source's stack
height that exceeds good engineering practice or by any other dispersion
technique, except as provided in LAC 33:III.921.B. When the administrative
authority proposes to issue a permit to a source based on a good engineering
practice stack height that exceeds the height allowed by LAC
33:III.921.A.Good Engineering Practice (GEP) Stack Height.1 or
2, the administrative authority will notify the public of the availability of
the demonstration study and will provide opportunity for public hearing on it.
This Section does not restrict, in any manner, the actual stack height of any
source.
AUTHORITY NOTE:
Promulgated in accordance with
R.S.
30:2054.
