Current through Register Vol. 47, No. 17, September 10, 2024
(a)
General. The owner or
operator must comply with the metals standards provided by paragraphs (b), (c),
(d), (e), or (f) of this section for each metal listed in paragraph (b) of this
section that is present in the hazardous waste at detectable levels by using
appropriate analytical procedures.
(b)
Tier I feed rate screening
limits.
Feed rate screening limits for metals are specified in
Appendix I of this Subpart, as a function of terrain-adjusted effective stack
height and terrain and land use in the vicinity of the facility. Criteria for
facilities that are not eligible to comply with the screening limits are
provided in paragraph (b)(7) of this section.
(1)
Noncarcinogenic metals. The
feed rates of antimony, barium, lead, mercury, thallium, silver, nickel and
selenium in all feed streams, including hazardous waste and fuels, shall not
exceed the screening limits specified in Appendix I of this Subpart.
(i) The feed rate screening limits for
antimony, barium, mercury, thallium, silver, nickel and selenium are based on
either:
(A) An hourly rolling average as
defined in § 264.346(c)(6)(i)(b); or
(B) An instantaneous limit not to be exceeded
at any time.
(ii) The
feed rate screening limit for lead is based on one of the following:
(A) An hourly rolling average as defined in
§ 264.346(c)(6)(i)(b);
(B) An
averaging period of 2 to 24 hours as defined in § 264.346(c)(6)(ii) with
an instantaneous feed rate limit not to exceed 10 times the feed rate that
would be allowed on an hourly rolling average basis; or
(C) An instantaneous limit not to be exceeded
at any time.
(2)
Carcinogenic metals.
(i) The feed rates of arsenic, cadmium,
beryllium, and chromium in all feed streams, including hazardous waste, fuels,
and industrial furnace feedstocks shall not exceed values derived from the
screening limits specified in Appendix I of this Subpart. The feed rate of each
of these metals is limited to a level such that the sum of the ratios of the
actual feed rate to the feed rate screening limit, specified in Appendix I,
divided by ten to achieve a 1 E-6 ALCR level, shall not exceed 1.0, as provided
by the following equation:
Click to
view image
where:
n = number of carcinogenic metals
AFR = actual feed rate to the device for metal
"i"
FRSL = feed rate screening limit
provided by Appendix I of this Subpart for metal "i", divided
by 10 to achieve a 1 E-6 risk level for carcinogenic compounds.
(ii) The feed rate screening
limits for the carcinogenic metals are based on either:
(A) An hourly rolling average; or
(B) An averaging period of 2 to 24 hours as
defined in § 264.346(c)(6)(ii) with an instantaneous feed rate limit not
to exceed 10 times the feed rate that would be allowed on an hourly rolling
average basis.
(3) TESH.
(i) The terrain-adjusted effective stack
height is determined according to the following equation:
TESH = Ha + H1-Tr (9)
where:
Ha = Actual physical stack height
H1 = Plume rise as determined from
Appendix VI of this Subpart as a function of stack flow rate and stack gas
exhaust temperature.
Tr = Terrain rise within five kilometers
of the stack.
(ii) The stack
height (Ha) may not exceed good engineering practice (GEP) as specified in
40 CFR
51.100(ii).
(iii) If the TESH for a particular facility
is not listed in the table in the appendices, the nearest lower TESH listed in
the table shall be used. If the TESH is four meters or less, a value of four
meters shall be used.
(4)
Terrain type. The screening limits are a function of whether the
facility is located in noncomplex or complex terrain. A device located where
any part of the surrounding terrain within 5 kilometers of the stack equals or
exceeds the elevation of the physical stack height (Ha) is considered to be in
complex terrain and the screening limits for complex terrain apply. Terrain
measurements are to be made from U.S. Geological Survey 7.5-minute topographic
maps of the area surrounding the facility.
(5)
Land use. The screening
limits are a function of whether the facility is located in an area where the
land use is urban or rural. To determine whether land use in the vicinity of
the facility is urban or rural, procedures provided in Appendices IX or X to
§ 264.348 of these regulations shall be used.
(6)
Multiple stacks. Owners and
operators of facilities with more than one on-site stack from an incinerator,
boiler, industrial furnace, or other thermal treatment unit subject to controls
of metals emissions under a Federal or State RCRA operating permit or interim
status controls must comply with the screening limits for all such units
assuming all hazardous waste is fed into the device with the worst-case stack
based on dispersion characteristics. The worst-case stack is determined from
the following equation as applied to each stack:
K = HVT (10)
Where:
K = a parameter accounting for relative
influence of stack height and plume rise;
H = physical stack height
(meters);
V = stack gas flow rate
(m3 /second); and
T = exhaust temperature (
°K).
The stack with the lowest value of K is
the worst-case stack.
(7)
Criteria for facilities not eligible for screening limits. If any
criteria below are met, the Tier I (and Tier II) screening limits do not apply.
Owners and operators of such facilities must comply with either the Tier III
standards provided by paragraph (d) of this section or with the adjusted Tier I
feed rate screening limits provided by paragraph (e) of this section.
(i) The device is located in a narrow valley
less than one kilometer wide;
(ii)
The device has a stack taller than 20 meters and is located such that the
terrain rises to the physical height within one kilometer of the
facility;
(iii) The device has a
stack taller than 20 meters and is located within five kilometers of a
shoreline of a large body of water such as an ocean or large lake;
(iv) The physical stack height of any stack
is less than 2.5 times the height of any building within five building heights
or five projected building widths of the stack and the distance from the stack
to the closest boundary is within five building heights or five projected
building widths of the associated building; or
(v) The Director determines that standards
based on site-specific dispersion modeling are necessary to evaluate protection
of human health and the environment.
(8)
Implementation. The feed
rate of metals in each feedstream must be monitored to ensure that the feed
rate screening limits are not exceeded.
(c)
Tier II emission rate screening
limits.
Emission rate screening limits are specified in Appendix
I as a function of terrain-adjusted effective stack height and terrain and land
use in the vicinity of the facility. Criteria for facilities that are not
eligible to comply with the screening limits are provided in paragraph (b)(7)
of this section.
(1)
Noncarcinogenic metals. The emission rates of antimony, barium,
lead, mercury, thallium, and silver shall not exceed the screening limits
specified in Appendix I of this Subpart.
(2)
Carcinogenic metals. The
emission rates of arsenic, cadmium, beryllium, nickel and chromium shall not
exceed values derived from the screening limits specified in Appendix I of this
Subpart divided by ten to achieve a 1 E-6 ALCR level. The emission rate of each
of these metals is limited to a level such that the sum of the ratios of the
actual emission rate to the emission rate screening limit specified in Appendix
I shall not exceed 1.0, as provided by the following equation:
Click to
view image
where:
n = number of carcinogenic metals
AER = actual emission rate for metal "
i"
ERSL = emission rate screening limit
provided by Appendix I of this Subpart for metal" i" ,divided
by 10 to achieve a 1 E-6 risk level for carcinogenic compounds.
(3)
Implementation.
The emission rate limits must be implemented by limiting feed rates of the
individual metals to levels during the trial burn (for new facilities or an
interim status facility applying for a permit) or the periodic compliance test.
The feed rate averaging periods are the same as provided by paragraphs
(b)(1)(i) and (ii) and (b)(2)(ii) of this section. The feed rate of metals in
each feedstream must be monitored to ensure that the feed rate limits for the
feedstreams specified under § 264.346 or § 265.140 are not
exceeded.
(4)
Definitions and
limitations. The definitions and limitations provided by paragraph (b)
of this section for the following terms also apply to the Tier II emission rate
screening limits provided by paragraph (c) of this section: terrain-adjusted
effective stack height, good engineering practice stack height, terrain type,
land use, and criteria for facilities not eligible to use the screening
limits.
(5)
Multiple
stacks.
(i) Owners and operators of
facilities with more than one onsite stack from an incinerator, boiler,
industrial furnace, or other thermal treatment unit subject to controls on
metals emissions under a State RCRA operating permit or interim status controls
must comply with the emissions screening limits for any such stacks assuming
all hazardous waste is fed into the device with the worst-case stack based on
dispersion characteristics.
(ii)
The worst-case stack is determined by procedures provided in paragraph (b)(6)
of this section.
(iii) For each
metal, the total emissions of the metal from those stacks shall not exceed the
screening limit for the worst-case stack.
(d)
Tier III and Adjusted Tier I
site-specific risk assessments. The requirements of this paragraph apply
to facilities complying with either the Tier III or Adjusted Tier I controls,
except where specified otherwise.
(1)
General. Conformance with the Tier III metals controls must be
demonstrated by emissions testing to determine the emission rate for each
metal. In addition, conformance with either the Tier III or Adjusted Tier I
metals controls must be demonstrated by air dispersion modeling to predict the
maximum annual average off-site ground level concentration for each metal, and
a demonstration that acceptable ambient levels are not exceeded.
(2)
Acceptable ambient levels.
Appendices IV and V of this Subpart list the acceptable ambient levels for
purposes of this section. Reference air concentrations (RACs) are listed for
the noncarcinogenic metals and 10
-5 risk-specific doses (RSDs) are
listed for the carcinogenic metals. The RSD for a metal, divided by ten to
achieve a 1 E-6 ALCR level, is the acceptable ambient level for that metal
provided that only one of the four carcinogenic metals is emitted. If more than
one carcinogenic metal is emitted, the acceptable ambient level for the
carcinogenic metals is a fraction of the RSD as described in paragraph (d)(3)
of this section.
(3)
Carcinogenic metals.
(i) For the
carcinogenic metals, arsenic, cadmium, beryllium, nickel and chromium, the sum
of the ratios of the predicted maximum annual average off-site ground level
concentrations (except that on-site concentrations must be considered if a
person resides on site) to the risk-specific dose (RSD) divided by ten to
achieve a 1 E-6 ALCR level, for all carcinogenic metals emitted shall not
exceed 1.0 as determined by the following equation:
Click to
view image
n = number of carcinogenic compounds being evaluated in
the risk assessment;
j = type of carcinogenic compounds (i.e., metals, PCDD/F,
and organic PICs);
Predicted (or measured) Ambient Concentration of compound
"i" at the MEI using dispersion modeling;
Risk-Specific Dose (RSD) of compound "i" from Table V,
(or Agency-accepted health based standard)
(ii) Results of predicted maximum annual
average off-site ground level concentrations for carcinogenic metals shall be
summed with results for other carcinogenic compounds calculated in §
264.342 to produce an estimate of the overall increased lifetime cancer risk to
the hypothetical MEI.
(4)
Noncarcinogenic metals. For the noncarcinogenic metals, the
predicted maximum annual average off-site ground level concentration for each
metal shall not exceed the performance standards of this Subpart.
(5)
Multiple stacks. Owners and
operators of facilities with more than one on-site stack from a boiler,
industrial furnace, incinerator, or other thermal treatment unit subject to
controls on metals emissions under a RCRA operating permit or interim status
controls must conduct emissions testing (except that facilities complying with
Adjusted Tier I controls need not conduct emissions testing) and dispersion
modeling to demonstrate that the aggregate emissions from all such on-site
stacks do not result in an exceedance of the acceptable ambient
levels.
(6)
Implementation. Under Tier III, the metals controls must be
implemented by limiting feed rates of the individual metals to levels during
the trial burn (for new facilities or an interim status facility applying for a
permit) or the periodic compliance test. The feed rate averaging periods are
the same as provided by paragraphs (b)(1)(i) and (ii) and (b)(2)(ii) of this
section. The feed rate of metals in each feedstream must be monitored to ensure
that the feed rate limits for the feedstreams specified under § 264.346 or
§ 265.140 are not exceeded.
(e)
Adjusted Tier I feed rate screening
limits.
The owner or operator may adjust the feed rate screening
limits provided by Appendix I of this Subpart to account for site-specific
dispersion modeling. Under this approach, the adjusted feed rate screening
limit for a metal is determined by back-calculating from the acceptable ambient
levels provided by Appendices IV and V of this Subpart using dispersion
modeling to determine the maximum allowable emission rate. This emission rate
becomes the adjusted Tier I feed rate screening limit The feed rate screening
limits for carcinogenic metals are implemented as prescribed in paragraph
(b)(2) of this section.
(f)
Alternative implementation approaches.
(1) The Director may approve on a
case-by-case basis approaches to implement the Tier II or Tier III metals
emission limits provided by paragraphs (c) or (d) of this section alternative
to monitoring the feed rate of metals in each feedstream.
(2) The emission limits provided by paragraph
(d) of this section must be determined as follows:
(i) For each noncarcinogenic metal, by
back-calculating from the RAC provided in
Appendix IV of this Subpart to determine the allowable
emission rate for each metal using the dilution factor for the maximum annual
average ground level concentration predicted by dispersion modeling in
conformance with paragraph (h) of this section; and
(ii) For each carcinogenic metal by:
(A) Back-calculating from the RSD (divided by
ten to achieve a 1 E-6 ALCR level) provided in Appendix V of this Subpart to
determine the allowable emission rate for each metal if that metal were the
only carcinogenic metal emitted using the dilution factor for the maximum
annual average ground level concentration predicted by dispersion modeling in
conformance with paragraph (h) of this section; and
(B) If more than one carcinogenic metal is
emitted, selecting an emission limit for each carcinogenic metal not to exceed
the emission rate determined by paragraph (f)(2)(ii)(A) of this section such
that the sum for all carcinogenic compounds metals of the ratios of the
selected emission limit to the emission rate determined by that paragraph does
not exceed 1.0, using Equation 1 of this section.
(g)
Emission
testing.
(1)
General.
Emission testing for metals shall be conducted using the Multiple Metals Train
as described in Method 0060, Determinations of Metals in Stack Emissions, EPA
Publication SW-846, as incorporated by reference in § 260.11 of these
regulations.
(2)
Hexavalent
chromium. Emissions of chromium are assumed to be hexavalent chromium
unless the owner or operator conducts emissions testing to determine hexavalent
chromium emissions using procedures prescribed in Method 0061, Determination of
Hexavalent Chromium Emissions from Stationary Sources, EPA Publication SW-846,
as incorporated by reference in § 260.11 of these regulations.
(h)
Dispersion
modeling.
Dispersion modeling required under this section shall be
conducted according to methods recommended in appendix W of 40 CFR Part 51
("Guideline on Air Quality Models (Revised)" (1986) and its supplements), the
"Hazardous Waste Combustion Air Quality Screening Procedure" provided in
Appendix IX to § 264.348 of these regulations, or in "Screening Procedures
for Estimating Air Quality Impact of Stationary Sources, Revised" (incorporated
by reference in § 260.11) to predict the maximum annual average off-site
ground level concentration. However, on-site concentrations must be considered
when a person resides on-site.
(i)
Enforcement. For the
purposes of permit enforcement, compliance with the metals emission standards
and operating requirements specified in the facility's operating permit (under
§ 264.346) will be regarded as compliance with this section. However,
evidence that compliance with those permit conditions is insufficient to ensure
compliance with the requirements of this section may be "information"
justifying modification or revocation and re-issuance of a permit under §
100.61 of these regulations.
