[Federal Register Volume 59, Number 110 (Thursday, June 9, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-13667]
[[Page Unknown]]
[Federal Register: June 9, 1994]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 63
[AD-FRL-4892-6]
RIN 2060-AE04
National Emission Standards for Hazardous Air Pollutants (NESHAP)
(Secondary Lead Smelters)
AGENCY: Environmental Protection Agency (EPA).
ACTION: Notice of proposed rule; notice of public hearing.
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SUMMARY: This action proposes standards that would limit emissions of
hazardous air pollutants (HAP's) from new and existing secondary lead
smelters. The proposed standards partially implement section 112(d) of
the Clean Air Act (the Act) as amended in November 1990, which requires
the Administrator to regulate categories of major and area sources of
HAP's listed in section 112(b) of the Act. The intent of the standards
is to reduce HAP emissions from secondary lead smelters to the maximum
degree achievable through the application of maximum achievable control
technology (MACT). The EPA is also proposing to add secondary lead
smelters that are area sources to the list of source categories that
will be subject to MACT standards.
DATES: Comments. Comments must be received on or before August 8, 1994.
Public Hearing. If a request to speak at a public hearing is
received, the hearing will be held on July 11, 1994, beginning at 10
a.m. Requests to speak at a public hearing must be received by the EPA
by June 30, 1994.
ADDRESSES: Comments. Comments should be submitted (in duplicate, if
possible) to: Air and Radiation Docket and Information Center (6102),
Attention Docket No. A-92-43, U.S. Environmental Protection Agency, 401
M Street, SW., Washington, DC 20460. The Agency requests that a
separate copy also be sent to the contact person listed below.
Public Hearing. If a public hearing is requested, it will be held
at the EPA Office of Administration auditorium in Research Triangle
Park, North Carolina. Persons interested in attending the hearing or
wishing to present oral testimony should contact Mary Hinson,
Industrial Studies Branch (MD-13), U.S. Environmental Protection
Agency, Research Triangle Park, North Carolina 27711, telephone number
(919) 541-5601.
Background Information Document. The Background Information
Document (BID) for the proposed standard may be obtained from the
docket or from the US EPA Library (MD-35), Research Triangle Park,
North Carolina 27711, telephone number (919) 541-2777. Please refer to
``Secondary Lead Smelting--Background Information Document for Proposed
Emissions Standards,'' EPA No. EPA-450/R-94-024.
Docket. Docket No. A-92-43 contains supporting information used in
developing the proposed standards. The docket is located at the U.S.
Environmental Protection Agency, 401 M Street, SW., Washington, DC
20460 in room M-1500, Waterside Mall (ground floor), and may be
inspected from 8:30 a.m. to 12 p.m. and 1 to 3 p.m., Monday through
Friday. The proposed regulatory text and other materials related to
this rule making are available for review in the docket or copies may
be mailed on request from the Air Docket by calling (202) 260-7548. A
reasonable fee may be charged for copying docket materials.
FOR FURTHER INFORMATION CONTACT: For information concerning the
proposed standards and technical aspects of secondary lead smelting
emissions and control, contact Mr. George Streit at (919) 541-2364,
Industrial Studies Branch, Emission Standards Division (MD-13), U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina
27711. For information concerning the area source listing of secondary
lead smelters, contact Ms. Dianne Byrne at (919) 541-5342, Pollutant
Assessment Branch, Emission Standards Division (MD-13) at the above
address.
SUPPLEMENTARY INFORMATION: The regulatory text of the proposed rule is
not included in this Federal Register notice, but is available in
Docket No. A-92-43 or by request from the Air Docket (see ADDRESSES).
If necessary, a limited number of copies is available from the EPA
contact persons designated earlier in this notice. This Notice with the
proposed regulatory language is also available on the Technology
Transfer Network (TTN), one of EPA's electronic bulletin boards. TTN
provides information and technology exchange in various areas of air
pollution control. The service is free, except for the cost of a phone
call. Dial (919) 541-5742 for up to a 14,400 bps modem. If more
information on TTN is needed, call the HELP line at (919) 541-5384.
The information presented in this preamble is organized as follows:
I. Initial List of Categories of Major and Area Sources
II. Background
A. Regulatory History
B. Description of Source Category
C. Emissions and Factors Affecting Emissions
D. Adverse Health Effects Finding for Area Sources
III. NESHAP Decision Process
A. Source of Authority for NESHAP Development
B. Criteria for Development of NESHAP
C. Determining the MACT Floor
IV. Summary of the Proposed Standards
A. Sources to be Regulated
B. Proposed Emission Limits for Process Sources
C. Proposed Standards for Process Fugitive Sources
D. Proposed Standards for Fugitive Dust Sources
E. Compliance Dates
F. Compliance Test Methods
G. Enhanced Monitoring Requirements
H. Notification Requirements
I. Recordkeeping and Reporting Requirements
V. Summary of Environmental, Energy, and Economic Impacts
A. Facilities Affected by This NESHAP
B. Air Quality Impacts
C. Water Quality Impacts
D. Solid Waste Impacts
E. Energy Impacts
F. Cost Impacts
G. Economic Impacts
VI. Rationale for Selecting the Proposed Standards
A. Selection of Pollutants and Source Category
B. Selection of Affected Sources
C. Selection of Basis and Level for the Proposed Standards for
New and Existing Sources
D. Selection of the Format for the Proposed Standards for New
and Existing Sources
E. Selection of Emission Limits and Equipment and Work Practice
Standards
F. Reconstruction Considerations
G. Selection of Compliance Dates
H. Selection of Emission Test Methods and Schedule
I. Selection of Proposed Enhanced Monitoring Requirements
J. Selection of Notification Requirements
K. Selection of Recordkeeping and Reporting Requirements
L. Operating Permit Program
M. Whether to Also Regulate Air Emissions Under RCRA
N. Solicitation of Comments
VII. Administrative Requirements
A. Public Hearing
B. Docket
C. Executive Order 12866
D. Paperwork Reduction Act
E. Regulatory Flexibility Act
F. Pollution Prevention Considerations
G. Miscellaneous
VIII. Statutory Authority
I. Initial List of Categories of Major and Area Sources
Section 112 of the Act requires that the EPA promulgate regulations
requiring the control of HAP emissions from major and area sources. The
control of HAP's is achieved through promulgation of emission standards
under sections 112(d) and (f) and work practice standards under section
112(h) for categories of sources that emit HAP's.
An initial list of categories of major and area sources of HAP's
selected for regulation in accordance with section 112(c) of the Act
was published in the Federal Register on July 16, 1992 (57 FR 31576).
Secondary lead smelters is one of the 174 categories of sources listed.
The category consists of smelters that recycle lead-bearing scrap
materials, primarily lead-acid batteries, into lead metal. The listing
was based on the Administrator's determination that secondary lead
smelters may reasonably be anticipated to emit several of the 189
listed HAP's in quantities sufficient to designate them as major
sources. Information subsequently collected by the EPA as part of this
rulemaking confirms that two-thirds of operating secondary lead
smelters have the potential to emit greater than 9.1 megagrams per year
(Mg/yr) [10 tons per year (tpy)] of a single HAP or greater than 22.7
Mg/yr (25 tpy) of a combination of HAP's and, therefore, are major
sources.
Section 112(c)(3) directs the Administrator to list each category
of area sources that the Administrator finds presents a threat of
adverse effects to human health or the environment warranting
regulation. The EPA performed an assessment of the remaining one-third
of the secondary lead smelters not qualifying as major sources to
determine whether the listing of these area sources for regulation
under section 112(c)(3) was justified. Based on a detailed assessment
of emissions, population exposure, and known and suspected health
effects, the Administrator proposes finding that the threat of adverse
effects to human health from area sources in the secondary lead smelter
category is sufficient to support regulation. Smelters designated as
area sources would, under the proposed regulation, be subject to the
same standards as smelters qualifying as major sources. The rationale
for this area source listing is presented in more detail in section
II.D of this preamble.
The secondary lead smelters category was originally in the group of
categories for which final regulations are scheduled for promulgation
by November 15, 1994. Final regulations are now scheduled for
promulgation by May 31, 1995 (58 FR 63952-63953) in accordance with a
consent decree entered in Sierra Club v. Browner, Case Number 93-0124
(and related cases) (D.D.C. 1993).
II. Background
A. Regulatory History
The EPA promulgated new source performance standards (NSPS) for
secondary lead smelters on March 8, 1974 (40 CFR part 60, subpart L).
The NSPS limit emissions of particulate matter (PM) from blast and
reverberatory furnaces (including rotary furnaces) to a concentration
of 50 milligrams per dry standard cubic meter (mg/dscm) [0.022 grains
per dry standard cubic foot (gr/dscf)] and emissions from refining
kettles (pot furnaces) to 10 percent opacity. Secondary lead smelters
are also subject to state regulations enacted to prevent violations of
the National Ambient Air Quality Standards (NAAQS) for lead. In
addition, about one-half of smelters are subject to permit conditions
developed under the Prevention of Significant Deterioration provisions
of the Act.
Secondary lead smelters must also obtain hazardous waste storage
permits pursuant to the Resource Conservation and Recovery Act (RCRA)
to store spent lead-acid batteries before smelting them (40 CFR
266.80(b)). Air emissions from smelting activities, however, are not
presently regulated under the hazardous waste rules (40 CFR
266.100(c)).
On July 16, 1992, the EPA published an initial list of categories
of major and area sources selected for regulation in accordance with
section 112(c) of the Act (57 FR 31476). Secondary lead smelters were
among the listed categories. On December 3, 1993, the EPA published a
schedule for the promulgation of standards for the sources selected for
regulation under section 112(c). According to this schedule,
regulations for secondary lead smelters must be promulgated no later
than May 31, 1995 (58 FR 63941). Today, the EPA is issuing a notice of
proposed rulemaking for secondary lead smelters and is soliciting
comments on the proposed rule.
Air emissions from secondary lead smelters may also potentially be
subject to regulation under the rules implementing RCRA. This is
because the principal feed material to these devices, scrap lead-acid
batteries, is a spent material being reclaimed, and hence is defined as
a solid and (by virtue of the lead content) hazardous waste (40 CFR
261.2 (a)(2)(i), (c)(3), and Ilco v. EPA, 996 F. 2d 1126 (11th Cir.
1993)). In 1991, the EPA decided to defer RCRA standards for the air
emissions from these devices, in large part because the forthcoming
Clean Air Act MACT standards might make further RCRA controls
unnecessary (56 FR 7142 (Feb. 21, 1991)) (40 CFR 266.100(c)). In
proposing this rule, EPA believes that this rule also satisfies the
goals and objectives of RCRA so that any further RCRA regulation of air
emissions would be unnecessary. The EPA is specifically soliciting
comments on this decision.
B. Description of Source Category
Secondary lead smelters are recycling facilities that use blast,
rotary, reverberatory, and/or electric furnaces to recover lead metal
from lead-bearing scrap materials, primarily lead-acid batteries. The
secondary lead smelters source category does not include remelters and
refiners or primary lead smelters.
There are 23 secondary lead smelters in the United States, although
only 16 of them were operating as of December 1993. Smelters often
close temporarily when the price of lead is low. A current trend in the
industry is toward fewer but larger smelters, although overall industry
capacity has been relatively constant.
Lead-acid batteries represent about 90 percent of the lead-bearing
raw materials at a typical secondary lead smelter. The majority of
these batteries are automotive-type batteries and the remainder are
industrial and uninterruptible power supply batteries. The other 10
percent of lead-bearing materials are battery plant scrap, defective
batteries, drosses from refining operations, and other scrap such as
lead pipes and roof flashing.
About 98 percent of all lead-acid batteries are recycled at
secondary lead smelters. The remaining 2 percent are either stored
indefinitely in residential basements and garages, disposed of as
municipal solid waste, or dumped illegally. Secondary lead smelters,
however, represent the only acceptable disposal option for used
batteries, and these smelters also recover or treat the plastic case
material and sulfuric acid from automotive-type batteries.
The secondary lead smelting process consists of: (1) Breaking lead-
acid batteries and separating the lead-bearing materials from the other
materials, including the plastic case material and acid electrolyte,
(2) melting lead metal and reducing lead compounds to lead metal in the
smelting furnace, and (3) refining and alloying the lead to customer
specifications.
Battery breaking is accomplished using hammermills to crush whole
batteries. Saws are used at some blast furnace smelters to cut open
batteries so that the lead grids from inside the battery can be removed
intact as whole units. The empty cases are then sent to a hammermill
for crushing. Following battery breaking, a sink/float separator is
used to separate the lead-bearing materials from the polypropylene
plastic from the battery cases, which is sold for recycling.
The lead-bearing components are then sent directly to a materials
storage and handling area or are chemically treated to remove the
sulfur in the lead paste attached to the battery grids. The
desulfurization step is performed to reduce sulfur emissions from the
smelting furnace and to improve furnace efficiency.
Lead-bearing materials are typically stored in bins or enclosures
before being charged to the smelting furnaces. If the storage area is
not totally enclosed, the storage piles and the roadways between them
are usually kept wet to prevent the formation of dust that may cause
fugitive emissions. Materials are handled within the smelter by front-
end loaders, enclosed screw conveyors, and belt- or pan-type conveyors.
Broken battery components are charged to the smelting furnaces
along with lead-bearing slag, dross, flue dust recycled from the air
pollution control devices, fluxing agents (including iron, silica sand,
and limestone or soda ash), and coke. Fluxing agents are added to blast
and rotary furnaces to promote the conversion of lead compounds to lead
metal. Coke is added to blast furnaces as a fuel and to rotary and
reverberatory furnaces as a fluxing agent. A dryer may be used prior to
charging a reverberatory furnace to remove moisture from the charge
materials. A dryer is typically a large, rotating chamber heated to
about 200 deg.C (400 deg.F) by a gas-fired burner. The exhaust from
the dryer is drawn directly into the reverberatory furnace.
Smelting is performed in reverberatory, blast, rotary, or electric
smelting furnaces. Reverberatory and blast furnaces are the most common
types of smelting furnaces. Reverberatory furnaces are always operated
in conjunction with a blast furnace or an electric furnace. Blast and
rotary furnaces may be operated independently of other furnace types.
All smelting furnaces operate at a temperature of about 980 to 1,200
deg.C (1,800 to 2,200 deg.F).
Blast furnaces are vertical shaft furnaces that use coke as a fuel
source. The combustion zone of the furnace is at the bottom of the
vertical shaft, where combustion air is injected through tuyeres. The
combustion gases then pass through a thick column of charge material
before being vented to a control device. Exhaust temperatures are
relatively cool, typically about 420 to 480 deg.C (800 to 900 deg.F).
Rotary furnaces consist of a rotating, refractory-lined cylinder
and are fired in the same way as reverberatory furnaces. Unlike other
smelting furnaces, which are operated on a continuous basis, rotary
furnaces are operated on a batch cycle consisting of charging,
smelting, and tapping of lead and slag.
Blast and rotary furnaces produce hard and semi-soft lead,
respectively, by adding soda ash (Na2CO3) or limestone
(CaCO3) to the charge materials as fluxing agents. These fluxing
agents promote the reaction of lead sulfate (PbSO4) and carbon
(from coke) to reduce the PbSO4 to elemental lead. The fluxing
agents, however, also promote the reduction of oxides of alloying
metals to their elemental forms. These metals are tapped from the
furnace with the lead in the form of a hard or semi-soft lead alloy.
Reverberatory furnaces are rectangular, refractory-lined furnaces
that use natural gas- or propane-fired jets to heat the walls and roof
of the furnace and the charge materials. Reverberatory furnaces are
used to produce soft (nearly pure) or semi-soft lead by reducing lead
compounds to metallic form, but at the same time oxidizing the alloying
elements so that they are removed in the slag. Therefore, soda ash and
limestone fluxing agents are added to reverberatory furnaces in much
smaller quantities than to blast or rotary furnaces.
Reverberatory furnace slag has a much higher lead content than
blast or rotary furnace slag because of the lower reducing conditions
of the furnace. This slag must be processed in a blast or electric
furnace to recover the remaining lead fraction. For this reason,
reverberatory furnaces are always operated in conjunction with a blast
or electric furnace.
There is only one electric furnace in use in the U. S. secondary
lead industry. It is collocated with a reverberatory furnace at one of
three smelters owned by the same company. The electric furnace is only
used to process reverberatory furnace slag from the furnace with which
it is collocated and slag shipped in from the company's other two
smelters. The charge materials in the furnace are heated by passing an
electric current through them. The electric furnace produces a hard
lead similar to that from a blast furnace.
Blast, rotary, and electric furnaces produce a final slag that
cannot be recycled and that must be disposed of as a solid waste. This
slag, however, may qualify as a hazardous waste and must be disposed of
in an approved landfill.
The lead tapped from smelting furnaces is refined and alloyed in
open-top refining kettles that are heated from underneath by a gas-
fired burner. Impurities are removed from the molten lead as drosses
that float on the surface of the lead. Drosses often have a high lead
content and are therefore recycled to the smelting furnace. After
refining, lead is pumped from the refining kettle into a machine for
casting into ingots. These ingots are stored at the smelter before
being shipped to a customer or transferred to a collocated battery
manufacturing facility.
Flue dust collected from baghouses at secondary lead smelters is
recycled to the smelting furnaces for recovery of the lead content. At
smelters that operate blast furnaces, an agglomerating furnace is used
to heat and melt the flue dust so that it can be cast into molds before
being recycled to the furnace. This is done to facilitate handling of
the dust and to prevent the dust from clogging the blast furnace charge
column.
C. Emissions and Factors Affecting Emissions
Hazardous air pollutants are emitted from secondary lead smelters
as: (1) Process emissions contained in the primary exhaust of smelting
furnaces, (2) process fugitive emissions associated with charging and
tapping of smelting furnaces and lead refining kettles, and (3)
fugitive dust emissions from wind or mechanically induced entrainment
of dust from stockpiles and plant yards and roadways.
1. Process Emissions
Smelting furnaces are sources of all three classes of HAP's: metal,
organic, and acid gas [chlorine (Cl2) and hydrochloric acid
(Hcl)]. The mix and relative quantities of potential emissions are
highly dependent on furnace type and use. Metal HAP emissions from
process sources are produced through the volatilization of the metals
contained in the feed materials by the elevated smelting temperatures
or by the entrainment of metal-containing PM in the furnace exhaust.
All smelting furnace types emit substantial quantities of metal
compounds, ranging from 40 to 100 Mg/yr (uncontrolled). About 70
percent of metal HAP emissions are lead compounds, with lesser amounts
of antimony, arsenic, and other metal compounds. Controlled emissions,
however, are typically less than 1 Mg/yr.
Organic HAP emissions from smelting furnaces result from incomplete
combustion of organic-containing materials (coke, plastic separators,
and hard rubber battery case material) in the furnace charge, as well
as coke and other fuels used for combustion. The emissions potential
for organic HAP's is highly variable. Blast furnaces typically emit
larger amounts of organic HAP's than other furnace types. A typical
uncontrolled blast furnace can emit over 100 Mg/yr of a mixture of
about 30 organic HAP's. The most predominant HAP's are benzene, carbon
disulfide, 1-3-butadiene, methyl chloride, and styrene. Also found in
blast furnace emissions are trace amounts of dioxins/furans. Emissions
of 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), which is a HAP,
are about 0.07 grams per year from a typical blast furnace. Emissions
of total dioxins/furans, expressed as 2,3,7,8-TCDD toxic equivalents
are about 0.3 grams per year.
Reverberatory and rotary furnaces have comparatively low organic
HAP emissions. Uncontrolled emissions from a typical furnace are less
than 4 Mg/yr of a mixture of about 25 or 30 organic HAP's. The most
predominant are benzene, 1-3-butadiene, formaldehyde, and styrene.
Reverberatory and rotary furnaces are operated at much higher flue gas
temperatures [about 980 to 1,200 deg.C (1,800 to 2,200 deg.F)] and
turbulence and achieve more complete combustion than blast furnaces. As
a result, reverberatory and rotary furnaces tend to have much lower
organic HAP emissions. Emissions of dioxins/furans from these furnaces
are near or below detection limits.
The one electric furnace now in operation processes only slag
(which contains little, if any, organic material) and uses no coke or
other fossil fuel. Therefore, organic HAP emissions are presumed to be
very low. This presumption is confirmed by CO emissions of only 1.1
kilograms per hour (kg/hr) [2.5 pounds per hour (lb/hr)] and a CO
concentration of 26 parts per million by volume (ppmv), according to
the results of a test conducted by the smelter operator (Docket A-92-
43, Item No. II-B-8).
For reverberatory/blast furnace configurations, a substantially
lower level of organic HAP emissions is possible than for blast
furnaces alone. Commingling (blending) the blast furnace exhaust
(temperature about 500 deg.C) and the much hotter reverberatory
furnace exhaust (about 1,000 deg.C) contributes significantly to the
destruction of the organic HAP compounds in the blast furnace exhaust.
Organic HAP emissions from such a commingled configuration are also
about 4 Mg/yr.
All smelting furnaces that process broken batteries are potential
sources of Hcl and Cl2 emissions. Many used lead-acid batteries
contain polyvinyl chloride (PVC) plastic separators between the battery
grids, although the use of PVC plastic as a separator material has been
discontinued by most battery manufacturers. These separators are
typically not removed from the lead-bearing parts of the battery during
the battery breaking and separation process. When the PVC plastic is
burned in the smelting furnace, the chlorides are released as HCl,
Cl2, and chlorinated hydrocarbons.
In blast furnaces and rotary furnaces, soda ash or limestone are
used as fluxing agents to increase the reduction of lead compounds to
elemental lead. These fluxing agents also combine with the chlorine in
the charge materials to form sodium chloride (NaCl) and calcium
chloride (CaCl2) salts, which are removed with the slag. As a
result, these furnaces have low HCl and Cl2 emissions, typically
less than 1 Mg/yr total.
In reverberatory furnaces, however, much less fluxing agent is
added to the charge material than in blast or rotary furnaces in order
to produce a soft lead product. Less of the chlorine is removed in the
slag and, therefore, reverberatory furnaces have higher HCl and
Cl2 emissions than blast or rotary furnaces, about 100 Mg/yr of
HCl and 4 Mg/yr of Cl2.
The one electric furnace in use is not a source of HCl or Cl2
emissions because it processes only slag from a reverberatory furnace
to which fluxing agents are added. Any chlorine present in the slag
should be in the form of CaCl2 or NaCl and cannot be emitted as
HCl or Cl2.
2. Process Fugitive Emissions
Process fugitive emissions result from furnace charging, lead and
slag tapping, lead refining and casting, dust agglomerating, and
battery breaking. Process fugitive emissions contain metal HAP's and,
in some cases, organic HAP's. Total uncontrolled metal HAP emissions
from all process fugitive sources at a typical smelter range from 10 to
80 Mg/yr, depending on smelter capacity. Metal HAP emissions are
independent of furnace configuration. Controlled metal HAP process
fugitive emissions are typically less than 1 Mg/yr.
Depending on charging method, hood design, and ventilation rate,
organic HAP's may be found in the process fugitive emission stream from
blast furnace charging. An improper balance between the ventilation
rate of the hood over the furnace charging chute and the primary
exhaust gas off-take can result in process emissions being drawn into
the process fugitive control system. The escaping organic HAP emissions
may be as high as 50 Mg/yr, based on measurements made at one facility
at which this problem was detected. Organic HAP emissions from a
properly balanced system should be less than 0.5 Mg/yr.
3. Fugitive Dust Emissions
Fugitive dust emissions result from the entrainment of dust due to
material handling, vehicle traffic, and wind erosion from storage
piles. Fugitive dust emissions contain only metal HAP's. The quantity
of fugitive dust emissions is dependent on the size of the facility and
the fugitive dust controls and practices in place. These emissions
cannot be measured and can only be roughly estimated using emission
factors and facility-specific data. Estimates of fugitive dust
emissions from all smelters range from 1 to 19 Mg/yr.
D. Adverse Health Effects Finding for Area Sources
As stated previously, the EPA today is proposing to add secondary
lead smelters that are area sources to the list of source categories
that will be subject to emission standards. In order to list categories
of area sources, the EPA must find a threat of adverse health or
environmental effects warranting regulation under section 112.
Section 112(a) contains no accompanying definition of adverse
health effect. The area source provisions of section 112(k) directing
regulation of area sources in urban areas, however, are closely linked
to section 112(c) and state that health effects considered under this
program shall include, but not be limited to, carcinogenicity,
mutagenicity, teratogenicity, neurotoxicity, reproductive dysfunction,
and other acute and chronic effects [section 112(k)(2)]. The term
``adverse environmental effect'' is defined in section 112(a) as ``any
significant and widespread adverse effect, which may reasonably be
anticipated, to wildlife, aquatic life, or other natural resources,
including adverse impacts on populations of endangered or threatened
species or significant degradation of environmental quality over broad
areas.''
In the finding for secondary lead area sources, quantitative
assessments of risk are an important consideration in assessing
significant threats of adverse health effects. Quantitative risk
assessment, in this context, means the estimation of a mathematical
probability of an individual or population being subject to some
adverse health effect, such as cancer. The EPA has historically
developed assessments of potential cancer risks, both to maximally
exposed individuals and populations, as part of its regulatory actions
under the previous version of section 112. Population risks are
expressed in terms of the total number of cancer cases (i.e., cancer
incidence) that could be expected to occur in a given time within a
prescribed area, considering the exposure of the population within the
area to modeled ambient concentrations of toxic air pollutants. In this
finding, nationwide cancer incidence is expressed in cases per year. In
contrast, a maximum individual ``lifetime'' risk is expressed as the
risk of contracting cancer associated with the highest individual's
exposure to the modeled, maximum, long-term concentration of the listed
HAP's for an assumed life-span of 70 years. Typically, both these
cancer risk estimates are based on upper-bound estimates of cancer
potency and exposure. The EPA also considers, where possible, the
probability of non-cancer effects.
The finding proposed in today's notice is based only on health
effects from inhalation exposures. The EPA did not consider other
adverse environmental effects. Future findings for other source
categories may be based on environmental effects as well as human
health effects as the appropriate information becomes available.
Section 112(c) does not offer a ``bright line'' test for the EPA to
use in making an area source finding. Instead, considering the language
cited above, the EPA believes it has discretion to consider a range of
health effect endpoints and exposure criteria in making a finding of a
threat of adverse effects. In the finding, the EPA considers factors
such as the number of sources in a category, the quantity of emissions,
the toxicity of the HAP's, the potential for individual and population
exposures and risks, the geographical distribution of the sources, and
the reasonableness of control measures. Thus, both qualitative and
quantitative factors are considered in making a finding.
The EPA recognizes uncertainties in current estimates of risk based
on modeled concentrations and the use of several upper-bound risk
assumptions. The EPA acknowledges that current cancer risk estimates do
not reflect the true risk, but often represent a conservative risk
level that may be an upper bound that is unlikely to be exceeded. The
EPA intends to improve its risk estimation procedures in accordance
with internal guidance and through the risk assessment studies required
under sections 112(f), 112(o), and 303 of title III of the Act.
Today's finding is based on six smelters that the EPA believes fit
the definition of an area source plus one other that is borderline
between major and area. The smelters are located in six states and
approximately 17.6 million people reside within 50 kilometers (about 30
miles) of the seven facilities. These people are considered by the EPA
to be exposed to HAP emissions from the smelters.
Secondary lead smelters emit a large number of pollutants. Of
these, EPA has performed scientific assessments that provide estimates
of the associated health risks of fourteen. Ten of the compounds have
unit risk estimates (URE or cancer potency estimates), three
(ethylbenzene, n-hexane, and toluene) have inhalation reference
concentrations (RfC), and one has a NAAQS (lead). In this finding,
elemental lead is being used as a surrogate for all lead compounds. The
reason for this is discussed below.
The health effects caused by increased blood lead levels are the
same, regardless of the lead compounds causing the exposure. However,
there are considerable differences in the bioavailability between lead
compounds. Unfortunately, there is little available literature on this
subject (Docket No. A-92-43, Item Nos. II-I-18 and II-I-29). The
literature that is available, however, does indicate that lead oxide,
which accounts for a substantial portion of the lead compounds emitted
from secondary lead smelters, is bioavailable. This indicates that
using lead as a surrogate for estimating health effects from the lead
compounds from this source category should be appropriate.
Lead is also a B2 carcinogen. However, a cancer risk factor has not
been developed for lead, so cancer rates associated with its exposure
can not be estimated.
Four of the ten potential carcinogens with quantitative assessments
are known human carcinogens and have URE's based on epidemiological
data. These are arsenic, benzene, and some chromium and nickel
compounds. The other potentially carcinogenic compounds have URE's
based on animal studies and are classified as either probable or
possible human carcinogens. These include acetaldehyde, 1,3-butadiene,
cadmium, formaldehyde, naphthalene, and 2,3,7,8-TCDD.
A URE is HAP-specific and equals the risk of cancer per unit of
lifetime pollutant exposure. It represents the probability of
developing cancer in a hypothetical individual, continuously exposed
throughout his/her life to 1 microgram per cubic meter (g/
m\3\) of the potential carcinogen in the air. An RfC is also HAP-
specific and is an estimate of the daily exposure to the human
population, including sensitive subpopulations, that is likely to be
without deleterious effects during a lifetime. The uncertainty of the
estimate can span an order of magnitude or more.
The estimated annual cancer incidence for the seven sources modeled
is low, approximately 0.1 incidence of cancer per year. However, the
EPA estimates that the upper-bound maximum individual lifetime cancer
risk associated with any one of the smelters ranges from 4 in 10,000 to
1 in 1,000. Furthermore, about 500 persons living in proximity to these
smelters are estimated to be subject to lifetime individual risks
possibly in excess of 1 in 10,000; over 40,000 are possibly subject to
lifetime individual risks above 1 in 100,000; and about 560,000 are
possibly subject to individual lifetime risks above 1 in 1 million. The
risks calculated are due to a mixture of pollutants, with arsenic and
1,3-butadiene posing the highest risks.
In addition to cancer risk, the EPA has examined the public health
risks associated with elevated blood lead levels. Little controversy
exists that high blood lead levels are associated with adverse health
effects, but there is also substantial concern regarding health effects
associated with lower blood lead levels as well: (1) Alterations in the
heme synthetic pathway may affect multiple organ system and
physiological functions, (2) children's IQ's may be lowered, (3)
impaired auditory function in children may affect language acquisition
and learning, and (4) animal experiments and human data have shown that
lead accumulates and is retained in the brain and other soft tissues
and can be remobilized from bone stores, resulting in a continuing risk
of lead toxicity even if exposure to lead is stopped.
Children may be particularly at risk as atmospheric lead deposits
on soils, crops, and street and playground surfaces. Soil lead, which
serves as a continuous source of outdoor and indoor (household) dusts
as well as a direct exposure route for young children, is relatively
insoluble and immobile and can continue to accumulate indefinitely.
Approximately 250 people are expected to be exposed to lead
concentrations that are above the current lead NAAQS of 1.5 g/
m\3\, calendar quarter average. Because the level of the lead NAAQS has
not been revised since it was established in 1978, the EPA also
determined potential exposure levels below the NAAQS. At 1.0
g/m\3\, the number of people potentially exposed is about 300,
rising to 1500 at 0.5 g/m\3\.
As stated above, the EPA did not evaluate environmental risks or
health risks associated with non-inhalation exposures because of a lack
of site-specific data and, in some cases, effects data. There is some
potential for increased risks due to exposure from metal compounds and
dioxins through routes of exposure such as ingestion of contaminated
soil, ingestion of food and water, and dermal contact. In addition, the
health effects from non-inhalation routes of exposure are not well
known for many air pollutants, and data on environmental effects are
even more scarce.
The EPA is proposing to regulate secondary lead smelters as area
sources, subject to consideration of public comment, because emissions
associated with these sources may present a threat of adverse health
effects. The upper-bound, maximum lifetime individual risks resulting
from exposure to arsenic and 1,3-butadiene are of particular concern.
The EPA, therefore, requests comments on the proposal to regulate these
sources as area sources and the appropriate criteria to be used in
making these decisions. In particular, the EPA requests comment on
whether the number of sources, the quantity of emissions, the toxicity
of the HAP's, the potential for individual and population exposures and
risks, the geographical distribution of the sources, and the
reasonableness of control measures justify a decision to regulate area
sources within this category.
The EPA notes that the exposures, the cancer incidence, and the
maximum individual risk associated with these area sources are all
below levels that have prompted the Administrator to designate other
categories of area sources for regulation. However, the relatively low
costs associated with regulation and the small number of area sources
in this category appear to warrant such regulation. The EPA requests
comment on whether regulation of these areas sources is warranted.
III. NESHAP Decision Process
A. Source of Authority for NESHAP Development
Section 112 specifically directs the EPA to develop a list of all
categories of all major and such area sources as appropriate emitting
one or more of the 189 HAP's listed in section 112(b) (section 112(c)).
Section 112 of the Act replaces the previous system of pollutant-by-
pollutant health-based regulation that proved ineffective at
controlling the high volumes and concentrations of HAP's in air
emissions. The provision directs that this deficiency be redressed by
imposing technology-based controls on sources emitting HAP's, and that
these technology-based standards may later be reduced further to
address residual risk that may remain even after imposition of
technology-based controls. A major source is any source that emits or
has the potential to emit 10 tons of any one HAP or 25 tons of any
combination of HAP's. The EPA published an initial list of source
categories on July 16, 1992 (57 FR 31,586), and may amend the list at
any time. (The EPA is proposing to add secondary lead smelters to the
list of area sources as part of this rulemaking, for example.)
B. Criteria for Development of NESHAP
The NESHAP are to be developed to control HAP emissions from both
new and existing sources according to the statutory directives set out
in section 112, as amended. The statute requires the standard to
reflect the maximum degree of reduction of HAP emissions that is
achievable taking into consideration the cost of achieving the emission
reduction, any nonair quality health and environmental impacts, and
energy requirements.
Emission reductions may be accomplished through application of
measures, processes, methods, systems, or techniques, including, but
not limited to: (1) Reducing the volume of, or eliminating emissions
of, such pollutants through process changes, substitution of materials,
or other modifications, (2) enclosing systems or processes to eliminate
emissions, (3) collecting, capturing, or treating such pollutants when
released from a process, stack, storage, or fugitive emissions point,
(4) design, equipment, work practice, or operational standards
(including requirements for operator training or certification) as
provided in subsection (h), or (5) a combination of the above (section
112(d)(2)).
To develop a NESHAP, the EPA collects information about the
industry, including information on emission source characteristics,
control technologies, data from HAP emissions tests at well-controlled
facilities, and information on the costs and other energy and
environmental impacts of emission control techniques. The EPA uses this
information to analyze possible regulatory approaches.
Although NESHAP are normally structured in terms of numerical
emission limits, alternative approaches are sometimes necessary. In
some cases, for example, physically measuring emissions from a source
may be impossible, or at least impractical, because of technological
and economic limitations. Section 112(h) authorizes the Administrator
to promulgate a design, equipment, work practice, or operational
standard, or a combination thereof, in those cases where it is not
feasible to prescribe or enforce an emissions standard.
If sources in the source category are major sources, then a MACT
standard is required for those major sources. The regulation of the
area sources in a source category is discretionary. If there is a
finding of a threat of adverse effects on human health or the
environment, then the source category can be added to the list of area
sources to be regulated. Based on the area source finding described in
section II.D of this preamble, the EPA proposes to regulate secondary
lead smelters as area sources.
C. Determining the MACT Floor
After the EPA has identified the specific source categories or
subcategories of major sources to regulate under section 112, it must
set MACT standards for each category or subcategory. Section 112 limits
the EPA's discretion by establishing a minimum baseline or ``floor''
for standards. For new sources, the standards for a source category or
subcategory cannot be less stringent than the emission control that is
achieved in practice by the best-controlled similar source, as
determined by the Administrator (section 112(d)(3)).
The standards for existing sources can be less stringent than
standards for new sources, but they cannot be less stringent than the
average emission limitation achieved by the best-performing 12 percent
of existing sources (excluding certain sources) for categories and
subcategories with 30 or more sources, or the best-performing 5 sources
for categories or subcategories with fewer than 30 sources (section
112(d)(3)). There are fewer than 30 secondary lead smelters, so the
standards for existing sources will be based on the best-performing
five sources.
In developing the proposal, the EPA has interpreted the term
``average'' to be equivalent to ``median'' and the MACT floor has been
selected to represent the median of the five best-controlled sources.
The median of the five best-controlled sources was selected as the MACT
floor on the basis of control technology because insufficient emissions
data were available for determining an average emission limitation. An
emission source testing program was then conducted in order to
determine an appropriate limitation based on the MACT floor technology.
After the floor has been determined for a new or existing source in
a source category or subcategory, the Administrator must set MACT
standards that are no less stringent than the floor. Such standards
must then be met by all sources within the category or subcategory.
Section 112(d)(2) specifies that the EPA shall establish standards
that require the maximum degree of reduction in emissions of hazardous
air pollutants * * * 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 * * *
In establishing standards, the Administrator may distinguish among
classes, types, and sizes of sources within a category or subcategory
(section 112(d)(1)). For example, the Administrator could establish two
classes of sources within a category or subcategory based on size and
establish a different emissions standard for each class, provided both
standards are at least as stringent as the MACT floor for that class of
sources.
In addition, the Act provides the Administrator further flexibility
to regulate area sources. Area sources can be regulated by MACT.
However, section 112(d)(5) allows the Administrator to promulgate
standards for area sources that provide for the use of ``generally
available control technologies (GACT) or management practices.'' Area
source standards promulgated under this authority (GACT standards)
would not be subject to the MACT floors described above. Moreover, for
source categories subject to standards promulgated under section
112(d)(5), the EPA is not required to conduct a residual risk analysis
under section 112(f).
At the end of the data gathering and analysis, the EPA must decide
whether it is more appropriate to follow the MACT or the GACT approach
for regulating an area source category. (As stated previously, MACT is
required for major sources.) If all or some portion of the sources emit
less than 9.1 Mg/yr (10 tpy) of any one HAP or less than 22.7 Mg/yr (25
tpy) of total HAP's, then it may be appropriate to define subcategories
within the source category and apply a combination MACT/GACT approach:
MACT for major sources and GACT for area sources in a source category.
In the case of this proposed rulemaking for secondary lead smelters,
the EPA has decided to regulate both major and area sources by applying
MACT. The EPA knows of no technological or economic reasons why
secondary lead smelters that are area sources cannot achieve the same
level of control as those that are major sources.
The next step in establishing MACT standards is the investigation
of regulatory alternatives. With MACT standards, only alternatives at
least as stringent as the floor may be selected. Information about the
industry is analyzed to develop model plant populations for projecting
national impacts, including HAP emission reduction levels, costs,
energy, and secondary impacts. Several regulatory alternative levels
(which may be different levels of emissions control or different levels
of applicability or both) are then evaluated to select the regulatory
alternative that best reflects the appropriate MACT level.
The selected alternative may be more stringent than the MACT floor,
but the control level selected must be technically achievable. In
selecting a regulatory alternative that represents MACT, the EPA
considers the achievable emission reductions of HAP's (and possibly
other pollutants that are co-controlled), cost and economic impacts,
energy impacts, and other environmental impacts. The objective is to
achieve the maximum degree of emissions reduction without unreasonable
economic or other impacts (section 112(d)(2)). The regulatory
alternatives selected for new and existing sources may be different
because of different MACT floors, and separate regulatory decisions may
be made for new and existing sources.
The selected regulatory alternative is then translated into a
proposed regulation. The regulation implementing the MACT decision
typically includes sections on applicability, standards, test methods
and compliance demonstration, monitoring, reporting, and recordkeeping.
The preamble to the proposed regulation provides an explanation of the
rationale for the decision. The public is invited to comment on the
proposed regulation during the public comment period. Based on an
evaluation of these comments, the EPA reaches a final decision and
promulgates the standard.
IV. Summary of the Proposed Standards
A. Sources To Be Regulated
Standards are being proposed to limit HAP emissions from: (1)
Process sources, (2) process fugitive sources, and (3) fugitive dust
sources at secondary lead smelters.
Process source emissions are discharged as the main exhaust of a
smelting furnace through a chimney, flue, or ductwork. For the purpose
of establishing numerical limits for process source emissions, smelting
furnaces have been grouped into the following source types: (1)
Collocated reverberatory and blast furnaces (reverberatory/blast), (2)
reverberatory or rotary furnaces not collocated with a blast furnace,
(3) blast furnaces not collocated with a reverberatory furnace, and (4)
electric furnaces.
Process fugitive emission sources that would be regulated are
smelting furnace charging, smelting furnace lead and slag tapping, flue
dust agglomerating furnace operation, and refining kettles.
Fugitive dust emission sources that would be regulated are plant
yards and roadways subject to wind and vehicle traffic, materials
handling and storage areas, battery breaking areas, and smelting and
refining areas.
B. Proposed Emission Limits for Process Sources
Emission limits are being proposed for lead compounds, total
hydrocarbons (THC), and HCl and Cl2 emissions and opacity from
reverberatory, blast, reverberatory/blast furnace combination, rotary,
and electric furnaces. Limits are being proposed for lead compounds and
THC as surrogates for metal HAP's and organic HAP's, respectively.
Lead compound emissions from all smelting furnace configurations
(both new and existing) would be limited to a concentration of 2.0 mg/
dscm (0.00087 gr/dscf). Total hydrocarbon emissions from both new and
existing reverberatory/blast furnace configurations would be limited to
20 ppmv [expressed as propane at 4 percent carbon dioxide (CO2) to
correct for dilution]. Total hydrocarbon emissions from existing blast
furnaces would be limited to 360 ppmv (as propane) at 4 percent
CO2. Total hydrocarbon emissions from new blast furnaces would be
limited to 70 ppmv (as propane) at 4 percent CO2. There is no
proposed standard for THC emissions from reverberatory, rotary, or
electric furnaces.
Total HCl and Cl2 emissions from both new and existing
reverberatory/blast, blast, reverberatory, and rotary smelting furnace
configurations would be limited to 15 mg/dscm (0.0065 gr/dscf) at 4
percent CO2 to correct for dilution. There is no proposed standard
for HCl or Cl2 emissions from new and existing electric smelting
furnaces.
The proposed numerical emission limits for process sources are
summarized in table 1.
Table 1.--Summary of Proposed Standards for Process Sources
------------------------------------------------------------------------
Total
Lead THCa,b HCl and
Furnace configuration compounds (ppmv) Cl2a(mg/
(mg/dscm) dscm)
------------------------------------------------------------------------
Reverberatory/blast...................... 2 20 15
Blast:
Existing............................... 2 360 15
New.................................... 2 70 15
Reverberatory and rotary................. 2 None 15
Electric................................. 2 None None
------------------------------------------------------------------------
aTHC and HCl/Cl2 emissions limits are at 4 percent CO2 to correct for
dilution.
bConcentrations (ppmv) for THC are as propane.
C. Proposed Standards for Process Fugitive Sources
The proposed standards for process fugitive sources are in the form
of equipment and operating standards. The standards apply to both new
and existing sources. All secondary lead smelters would be required to
control process fugitive emission sources with capture hoods equivalent
in design and performance to those specified in the Occupational Safety
and Health Administration's ``Cooperative Assessment Program Manual for
the Secondary Lead Industry'' (Docket No. A-92-43, Item No. II-I-16).
The standards would require the following process fugitive sources
to be partially enclosed with a hood and ventilated: smelting furnace
and dryer charging hoppers and chutes, lead and slag tapping
operations, refining kettles, dryer transition pieces, and flue dust
agglomerating furnaces. All hoods, except those on refining kettles,
would be required to be designed and operated to achieve a face
velocity of at least 110 meters per minute (m/min) [350 feet per minute
(fpm)] at all openings. Refining kettle hoods would be required to be
designed and operated to achieve a face velocity of at least 75 m/min
(250 fpm) and a volumetric flow rate of at least 60 actual cubic meters
per minute per square meter [200 actual cubic feet per minute per
square foot (acfm/ft2)] of kettle surface area. All hoods would be
required to be ventilated to a control device with an outlet lead
compound concentration not to exceed 2.0 mg/dscm (0.00087 gr/dscf).
D. Proposed Standards for Fugitive Dust Sources
The proposed standards for fugitive dust sources are in the form of
work practice and operating standards. Again, the standards apply to
both new and existing fugitive dust sources. Each secondary lead
smelter would be required to develop a Standard Operating Procedures
(SOP) manual that details procedures to limit fugitive dust emissions.
Each smelter's SOP manual would be reviewed and subject to approval by
the Administrator.
The SOP manual would describe how each smelter would implement the
types of work practices and operating standards which EPA has
determined represent MACT controls for fugitive dust emissions. These
controls are specified in the proposed regulation and include cleaning
of paved areas through vacuuming or power-washing, use of water or
chemical dust suppression in materials storage and handling areas, use
of partial or total enclosures to prevent wind erosion of storage
piles, and use of measures to prevent crossdrafts from upsetting
process fugitive control hoods. The SOP manual would also indicate the
frequencies with which pavement cleaning and dust suppression are to be
performed, and which areas are partially and totally enclosed and which
are paved. The MACT controls specified in the proposed regulation would
serve as the criteria by which the Administrator would decide whether
or not to approve a smelter's SOP.
E. Compliance Dates
Compliance with the standards would be achieved within 24 months of
promulgation for existing secondary lead smelters, and upon startup for
new and reconstructed smelters.
F. Compliance Test Methods
Testing of lead compound emissions from process and process
fugitive emission control devices would be conducted according to EPA
reference method 12 (40 CFR part 60, appendix A). Testing of THC
emissions from process sources for reverberatory/blast and blast
furnace configurations would be conducted according to EPA reference
method 25A (40 CFR part 60, appendix A), and the results reported as a
concentration in ppmv, as propane, corrected to 4 percent CO2 for
dilution. Testing of HCl and Cl2 emissions would be conducted
according to EPA reference method 26A (59 FR 19306-19323), and the
results reported as HCl equivalents, in mg/dscm, corrected to 4 percent
CO2 for dilution. An average of three runs would be used to
determine compliance for lead compounds, THC, and total HCl and
Cl2.
Sampling locations for all compliance tests would be determined by
EPA reference method 1. Stack gas velocity and volumetric flow rate
would be determined by EPA reference method 2. Gas analysis would be
conducted according to EPA reference method 3 for CO2, oxygen,
excess air, and molecular weight on a dry basis. The Single Point
Integrated Sampling and Analytical Procedure of EPA reference method 3B
would be used to measure the CO2 content of the stack gas during
the THC and HCl/Cl2 compliance tests for correcting to 4 percent
CO2.
G. Enhanced Monitoring Requirements
Continuous opacity monitors (COM's) would be used on all process
control stacks to monitor compliance with the lead compound emission
limit. Opacity (based on a 6-minute average) greater than the maximum
opacity recorded during the initial lead compliance test (plus 2
percent opacity to allow for normal instrument drift) would be a
violation of the standard. Process fugitive and building ventilation
baghouse performance would be monitored through inspections of the
baghouses. Pressure drop and water flow rate would be monitored for PM
scrubbers used to control process fugitive sources.
Compliance with the THC standard would require either continuous
monitoring of incineration or afterburner temperature or continuous THC
monitoring for reverberatory/blast and blast furnace configurations.
The temperature would be maintained above a minimum established during
the initial THC compliance test. Operating at a lower temperature
(based on a 3-hour average) would constitute a violation of the
emissions standard. Alternatively, a facility could monitor THC
concentration directly with a THC continuous emissions monitor (CEM) if
desired.
Compliance with the HCl/Cl2 standard would require monitoring
of either: (1) The addition of soda ash and limestone to furnace charge
materials, (2) scrubber parameters (media pH and injection rate), (3)
sulfur dioxide (SO2) concentration, or (4) HCl concentration. The
quantity of soda ash and limestone, the scrubber parameters, or the
SO2 concentration would be maintained within allowable ranges
established during the initial HCl/Cl2 compliance test. Failure to
maintain these variables within the allowable ranges would constitute a
violation of the standard. An operator wishing to establish new
allowable ranges would have to demonstrate that compliance with the
HCl/Cl2 standard is still achieved. Alternatively, the operator
could monitor HCl concentration using an HCl CEM.
All COM's would be required to comply with Performance
Specification 1 in appendix B of 40 CFR part 60. If an owner or
operator chose to monitor SO2, the SO2 CEM would be required
to comply with Performance Specification 2 in appendix B of 40 CFR part
60. All CEM's would be required to comply with the Quality Assurance
Procedures found in appendix F of 40 CFR part 60.
H. Notification Requirements
The owner or operator of a secondary lead smelter would be required
to submit the notifications described in the General Provisions to part
63, (40 CFR part 63, subpart A). These would include the initial
notification, notifications of performance tests and continuous
monitoring system (including COM and CEM) performance evaluations, and
the notification of compliance status. In addition, each owner or
operator would be required to submit the SOP manual and a notification
to the Administrator requesting review and approval of the smelter's
fugitive dust control SOP manual.
I. Recordkeeping and Reporting Requirements
The owner or operator of a secondary lead smelter would be required
to retain for 5 years records of: (1) The results of initial and
subsequent compliance tests, (2) the recorded values for the parameters
that must be monitored to demonstrate continuous compliance, and (3)
records demonstrating implementation of the fugitive dust controls
contained in the smelter's SOP manual.
The owner or operator would be required to submit the quarterly
excess emissions and continuous monitoring performance reports,
including the results of annual and other compliance tests, as
prescribed in the General Provisions.
V. Summary of Environmental, Energy, and Economic Impacts
A. Facilities Affected by This NESHAP
The proposed standards would apply to all secondary lead smelters
in the United States, regardless of whether they are classified as a
major source or an area source under section 112(c). The EPA estimates
that 18 smelters would have to upgrade controls to reduce emissions.
All 23 existing smelters would be required to perform monitoring and
meet the requirements for recordkeeping and reporting. It is not
anticipated that any new smelters will be built over the next 5 years
because of the depressed price of lead and the excess capacity in the
industry.
B. Air Quality Impacts
Under the proposed standards, organic HAP emissions would be
reduced by approximately 1,200 Mg/yr (1,300 tpy). This represents an
approximately 70-percent reduction from estimated baseline emissions.
Metal HAP emissions would be reduced by 53 Mg/yr (58 tpy) through the
reduction of process fugitive emissions [29 Mg/yr (32 tpy)] and
fugitive dust emissions [24 Mg/yr (26 tpy)]. This represents a 20-
percent reduction from baseline metal HAP emissions. There would be no
reductions in metal HAP emissions from process sources. Hydrochloric
acid and Cl2 emissions would be reduced 720 Mg/yr (790 tpy). This
represents a 98-percent reduction from baseline emissions.
In addition to HAP reductions, criteria pollutant emissions would
also be reduced. Emissions of SO2 would be reduced by 7,400 Mg/yr
(8,100 tpy) if wet scrubbers were installed to control HCl/Cl2
emissions. Emissions of CO would be reduced by approximately 83,000 Mg/
yr (91,000 tpy) and THC emissions (including 1,200 Mg/yr of organic
HAP's) would be reduced by approximately 6,400 Mg/yr (7,000 tpy).
Controlling metal HAP emissions would also reduce PM emissions
(including 53 Mg/yr of metal HAP's) by 140 Mg/yr (150 tpy).
C. Water Quality Impacts
Direct water quality impacts from the proposed standards will vary
depending on which control option smelters choose in order to comply
with the proposed HCl/Cl2 emission limits. There would be no
wastewater impact if all smelters chose to eliminate HCl/Cl2
emissions through the addition of fluxing agents to the furnace feed
material and the removal of chlorides through slagging, which is the
least-cost option.
If wet scrubbers are installed to control HCl/Cl2 emissions,
about 27 million gallons of wastewater from scrubber blowdown would be
generated. This wastewater would require neutralization and settling
before being discharged to a publicly owned treatment works.
Evaporation of water from these scrubbers would be about 430 million
gallons per year. The evaporated water would require no treatment.
Because EPA does not believe smelters would adopt wet scrubbers as a
means of compliance, it is not soliciting comment as to whether the
existing effluent limitation guidelines for the secondary lead industry
should be amended to account for this source of wastewater.
Use of water for wet suppression and pavement cleaning to control
fugitive dust emissions could increase the amount of water runoff that
must be treated on site. This incremental increase in runoff would
represent less than 1 percent of the volume of water currently treated
at secondary lead smelters.
Several of the facilities which would be affected by this rule are
located in States adjacent to the Great Lakes. Because these facilities
would reduce their emissions of metals and organic HAP's, the indirect
water quality impacts of this rule are expected to be positive, albeit
difficult to quantify.
D. Solid Waste Impacts
The addition of fluxing agents to smelting furnaces to eliminate
HCl/Cl2 emissions through slagging would result in a slight
increase in the amount of slag that must be disposed of as solid waste.
This increase would represent only about 5 percent of the slag
currently generated by each of the six smelters that would be impacted.
If a smelter chose to install a scrubber to control HCl and
Cl2, a solid waste stream that would require disposal could be
generated if the smelter also elected to control SO2 emissions.
Scrubbers installed to control only HCl and Cl2 do not produce
solid waste. If two smelters that do not currently perform paste
desulfurization installed scrubbers to control SO2 emissions in
addition to HCl/Cl2 emissions, these scrubbers would generate as
much as 21,000 Mg/yr of solid waste as scrubber sludge.
Because secondary lead smelters typically process hazardous waste
that exhibits the toxicity characteristics for lead (40 CFR 261.24),
all of the residue generated from these facilities would have to
satisfy the standards for treatment prescribed in 40 CFR part 268 for
D008 (lead-bearing hazardous waste) before any residue can be land-
disposed. (Chemical Waste Management v. EPA, 976 F. 2d 2 (D.C. Cir.
1992).
Flue dust and sludge generated at secondary lead smelters are
listed as hazardous waste KO69 under 40 CFR 261.32, Hazardous Wastes
from Specific Sources. Flue dust collected by baghouses is recycled on
site to the smelting furnace at all smelters and is not disposed of as
a solid waste. Furthermore, the EPA has issued a limited administrative
stay so that the KO69 listing does not apply to sludges generated from
acid gas scrubber systems located at secondary lead smelters (56 FR
19951, May 1, 1991).
E. Energy Impacts
No significant increases in electricity consumption are expected as
a result of the proposed standards. Natural gas consumption is expected
to increase at six of the smelters with blast furnace configurations as
a result of installing afterburners or increasing afterburner
temperatures. The total increase in natural gas consumption at these
smelters is expected to be about 3.7 million cubic meters (130 million
cubic feet) per year.
F. Cost Impacts
The estimated nationwide capital and annualized costs of the
proposed standards would be $2,700,000 and $2,600,000, respectively.
These costs were estimated for all 23 smelters, including those that
are currently shut down, and include costs for monitoring,
recordkeeping, and reporting.
The estimated capital costs of reducing organic HAP emissions under
the proposed standards would be $1,100,000. Estimated annualized costs
would be $620,000. Ten smelters would be impacted. For the blast-
furnace-only configuration, costs incurred would be for the
installation and operation of new afterburners at four smelters and
increased natural gas consumption at two smelters. For the collocated
reverberatory/blast furnace configuration, costs incurred would be for
the retrofit of additional ductwork to achieve gas stream blending at
four smelters.
The estimated capital and annualized costs of reducing metal HAP
emissions would be $240,000 and $110,000, respectively. These costs
would be distributed over an estimated 14 smelters. The capital costs
would be for 1 smelter to upgrade its process fugitive emission
controls, and for that smelter and 13 others to upgrade their fugitive
dust emission controls. Upgrades would be in the form of improved
housekeeping, including the purchase of vacuum sweepers by four
smelters. Because all smelters currently operate at the level of the
proposed standard for metal HAP's, no anticipated reductions or costs
are associated with the control of metal HAP's from process sources.
No capital costs to reduce HCl/Cl2 emissions would be incurred
under the proposed standards if all smelters chose to control HCl/
Cl2 emissions through fluxing. The estimated annualized cost would
be $160,000, distributed over six smelters, for the purchase of
additional fluxing agents. If a smelter chose to install a scrubber to
control HCl/Cl2 emissions, the approximate capital cost would be
$1,700,000 and the annualized cost would be $850,000 for a
reverberatory furnace with a production capacity of 50,000 Mg/yr.
Enhanced monitoring and recordkeeping and reporting costs would be
incurred by all 23 smelters. These costs are estimated to be $73,000
per smelter per year and the total national cost is estimated to be
$1,700,000 per year. The only capital costs would be for COM's, for
which the total national cost is estimated to be $1,400,000. The
recordkeeping and monitoring cost estimate includes the costs for the
emission tests needed to demonstrate compliance. Only the tests for
lead emissions from process fugitive sources and building ventilation
systems are annual tests, so testing costs would be lower after the
initial compliance demonstration.
G. Economic Impacts
The Economic Impact Analysis evaluated: (1) The ability of
facilities to absorb annual control costs and obtain financing for
capital control costs, and (2) the market response to the regulation--
specifically, impacts on industry-wide output, employment, and revenue.
The analysis was performed on all 23 facilities in the industry,
including facilities that have shut down operations indefinitely but
have not closed permanently.
Because lead is an internationally traded commodity whose price is
determined by international market factors, secondary lead producers
have little influence on price. Therefore, the economic analysis
assumed that no price increase would occur and control costs would have
to be absorbed by affected facilities. Based on discussions with
industry experts, EPA formulated guidelines for estimating when a
facility would be significantly impacted. A facility would be
significantly impacted if either: (1) Total annualized control costs
result in more than a 1-percent increase over baseline cost of
production, or (2) capital control costs exceed 5 percent of baseline
total assets (company-wide) and post-regulation total liabilities
exceed two-thirds of baseline total assets if the capital control costs
are financed with debt.
The analysis indicates that up to 11 facilities would be
significantly impacted, depending on the level of the standards and the
amount of continuous monitoring required. Almost all of the
significantly impacted facilities are owned by small businesses because
of economies of scale and limited access to capital resources.
Implementation of emission controls equal to the MACT floor, the
basis for the proposed rule, results in significant impacts to two
facilities that are currently in operation. Three other facilities that
are currently shut down would also be impacted significantly. If
control levels are imposed at levels above the MACT floor, seven
facilities are significantly impacted. Of the seven facilities, four
sources are currently in operation and three are shut down. When
continuous opacity monitoring is required in addition to the MACT
floor, one additional source that is currently shut down is
significantly impacted.
If the MACT floor is considered with continuous opacity and THC
monitoring, nine facilities are significantly impacted. Of the nine
facilities, three sources are currently in operation and six are shut
down. If continuous monitoring for HCl is added, 11 facilities would be
significantly impacted. Of the 11 facilities, four sources are
currently in operation and seven are shut down.
Under any of the regulatory alternatives considered, industry
employment and output is reduced by less than 1-percent. At current
market conditions (December 1993), no closures are expected as a
consequence of the regulation. If the price of lead decreases to levels
observed over the past year, the possibility of closure increases for
two currently operating major sources. Under any of the regulatory
alternatives, all smelters currently shut down have additional
incentive to not reopen.
VI. Rationale for Selecting the Proposed Standards
This section describes the rationale for the decisions made by the
Administrator in selecting the proposed standards.
A. Selection of Pollutants and Source Category
Secondary lead smelters emit several of the 189 HAP's listed in
section 112(b) of the Act. Organic HAP's emitted by secondary lead
smelters include carbon disulfide, 1,3-butadiene, methyl chloride,
benzene, styrene, toluene, formaldehyde, and naphthalene. Metal HAP's
emitted include primarily compounds of lead, antimony, and arsenic,
with lesser quantities of compounds of chromium, nickel, manganese,
mercury, and cadmium. In addition, secondary lead smelters emit the
HAP's HCl and Cl2. Criteria pollutants emitted include lead, PM,
SO2, CO, and hydrocarbons.
Approximately two-thirds of the secondary lead smelters in the
United States are major sources of HAP's, based on potential-to-emit
estimates that take into account air pollution control measures
currently in place at each smelter. Furthermore, as described in
section II.D of this preamble, the Administrator has initially
determined that secondary lead smelters that are area sources of HAP's
present a threat of adverse effects to human health sufficient to
support adding secondary lead smelters to the list of area source
categories subject to regulation under section 112(c)(3) of the Act.
Consequently, the standards being proposed would apply to all new and
existing secondary lead smelters regardless of source (major or area)
designation.
The emission, equipment, and work practice standards being proposed
today would substantially limit emissions of metal HAP's, organic
HAP's, HCl, and Cl2 from secondary lead smelters. The standards
being proposed to address metal and organic HAP emissions establish
limits for surrogates rather than for individual compounds.
Establishing emission limits for each of the numerous metal and
organic HAP compounds emitted from secondary lead smelters is
considered impractical because measuring each compound would be too
costly and would pose unreasonable compliance and monitoring costs and
would achieve little, if any, emission reduction above the surrogate
pollutant approach. On the other hand, strong correlations exist
between emissions of the selected surrogate pollutants and emissions of
the pollutant classes they represent. In addition, the technologies
identified for the control of HAP's have equivalent performance on the
selected surrogates. Therefore, emissions standards requiring good
control of the selected surrogates will also achieve good control of
HAP's.
Candidate surrogates for the mix of metal HAP's present, including
lead compounds, are PM and lead, both of which are criteria pollutants.
The selected surrogate is lead. Compounds of lead are the most
prevalent metal HAP contained in secondary lead smelter emissions. In
addition, lead is concentrated, along with metal HAP's, in the smaller
size fractions of PM, which are the most difficult to control.
Therefore, controlling lead will also control metal HAP's. Available
data on the performance of baghouses used to control particulate
emissions at secondary lead smelters indicate a much stronger
correlation of metal HAP's with lead emissions than with total PM
(Docket No. A-92-43, Item Nos. II-A-1, II-A-2, II-A-3, II-I-1, and II-
I-9). Therefore, lead is a better surrogate than PM. Lastly, there is a
validated test method (EPA reference method 12) for the determination
of inorganic lead emissions from stationary sources.
The surrogate pollutant chosen for organic HAP's is THC. There are
much data to demonstrate that the destruction of THC through
incineration is strongly correlated with the destruction of organic HAP
compounds (Docket No. A-92-43, Item No. II-I-27, 56 FR 7155-56
(February 21, 1991)). In addition, THC is easily measured and can be
monitored. Carbon monoxide, another indicator of destruction efficiency
for organic compounds, was considered but dismissed. It does not
correlate as well as THC with destruction of organic HAP compounds. No
surrogates are needed for HCl and Cl2 because they can be measured
directly.
The proposed regulation does not establish explicit limits for
dioxin/furan emissions from secondary lead smelters for several
reasons. First, secondary lead smelters emit very small quantities of
dioxin. Cumulative annual emissions for the entire industry are
estimated to be only 1.6 grams of dioxin/furan, expressed in toxic
equivalents (Docket No. A-92-43, Item No. II-B-35). Emission rates from
the other two smelters (a reverberatory/blast smelter and a rotary
smelter) were an order of magnitude lower (Docket No. A-92-43, Item
Nos. II-A-1 and II-A-3). Second, the Agency believes that the emission
controls necessary to achieve the emission limitations associated with
this proposed standard would reduce dioxin/furan emissions,
particularly from blast furnaces. Finally, any risks associated with
dioxin will be addressed in the residual risk evaluation required
within eight years of promulgation of the standard pursuant to section
112(f) of the Act.
The Agency currently is in the process of revising its assessment
of the risks associated with the exposure to dioxin. The EPA requests
comment whether additional action is necessary to reduce dioxin
emissions from secondary lead smelters.
Facilities that solely melt scrap or refined lead for use in
specific molded or fabricated products would not be covered by the
proposed rule because they do not operate blast, reverberatory, rotary,
or electric smelting furnaces and, therefore, have substantially
different and lower emissions potential than do secondary lead
smelters.
Lead-acid battery manufacturing operations that may be collocated
with a secondary lead smelter and primary lead smelters that produce
refined lead from ore concentrate would not be covered by the proposed
rule because they are listed as separate categories in the list of
major sources to be regulated by MACT standards (57 FR 31576) in
separate rulemakings.
B. Selection of Affected Sources
The proposed standards apply to three types of emission sources at
secondary lead smelters: (1) Process sources, (2) process fugitive
sources, and (3) fugitive dust sources.
1. Process Sources
Affected process sources include all furnaces (blast,
reverberatory, rotary, or electric) used for smelting lead-bearing
scrap or slag. All smelting furnaces are equipped with chimneys, flues,
or ductwork that convey exhaust gases from the furnace. These exhaust
gases contain varying amounts of organic HAP's, metal HAP's, HCl, and
Cl2
Blast furnaces and collocated reverberatory and blast furnaces have
potentially large organic HAP emissions. Therefore, standards are being
proposed to limit organic HAP emissions from these furnace
configurations. Rotary furnaces, electric furnaces, and reverberatory
furnaces not collocated with blast furnaces have relatively low
potentials for organic HAP emissions and no standards are being
proposed to limit organic HAP emissions from these furnace
configurations. The MACT floor for these configurations does not
include add-on controls and the EPA does not believe that there is any
justification to be more stringent than the MACT floor because of the
small amounts of organic HAP emissions associated with these sources.
Collocated reverberatory and blast furnaces are being regulated as
a single source type because a greater level of control is achievable
when reverberatory and blast furnaces are collocated than when they are
not. Other furnace combinations have not been observed in this
industry.
All smelting furnaces have high uncontrolled emissions of metal
HAP's. Therefore, emission standards to limit lead emissions (as a
surrogate for metal HAP's) that would apply to all smelting furnace
types and configurations are being proposed.
All smelting furnaces that process lead-acid batteries are also
potential sources of HCl and C12 emissions because of the presence
of PVC plastic separators in the furnace feed. The amount of HCl and
Cl2 emitted will vary substantially depending on the quantity of
PVC in the feed and whether fluxing agents are added to promote the
elimination of chlorides through slagging. However, because all furnace
types (except electric furnaces) are potential sources, emission
standards are being proposed to limit HCl and Cl2 emissions from
all but electric smelting furnaces.
Electric furnaces are not sources of HCl or Cl2 emissions
because the chlorine present in the feed material is in the form of
NaCl or CaC2 and cannot be released during smelting. However, the
proposed regulation defines electric smelting furnaces to include only
those that process reverberatory furnace slag as the lead-bearing
material charged to the furnace. No electric furnaces that process
other lead-bearing materials are currently in use.
2. Process Fugitive Sources
The following process fugitive sources were selected for
regulation: (1) Smelting furnace and dryer charging hoppers and chutes
(the furnace and dryer openings into which materials are charged), (2)
lead taps and molds, (3) slag taps and molds, (4) refining and alloying
kettles, (5) dryer transition pieces, and (6) flue dust agglomerating
furnace taps and molds. All process fugitive sources are potential
emission points of metal HAP's. Blast furnace charging emissions may
also contain organic HAP's if there is leakage of primary exhaust gases
into the ventilation hood over the charging chute.
The EPA is not proposing standards for battery breaking equipment
(e.g., rotary hammermills, saws, and shears) or lead casting machines.
Many smelters do not have add-on controls for metal HAP's for these
sources so that the MACT floor is no control. The EPA does not believe
there is any justification for controls more stringent than the floor.
Battery breakers are small sources of metal HAP emissions [about 18
kilograms (40 pounds) per year per battery breaker] compared to other
sources, and they emit relatively large particles that settle out
quickly from the air in the battery breaking area. The proposed NESHAP
would require fugitive dust controls in the battery breaking area that
would control potential emissions from these settled particles. Casting
machines that are used to cast refined lead into ingots are also small
sources of metal HAP emissions because the molten lead in the molds is
below the fuming temperature of lead. Therefore, casting machines are
not included in the proposed regulation.
3. Fugitive Dust Sources
Fugitive dust sources selected for regulation are the following:
(1) The battery breaking area, (2) the materials storage and handling
area (including, but not limited to, areas in which slag and flue dust
are stored), (3) the smelting furnace area, (4) the refining and
casting area, and (5) plant yards and roadways. Fugitive dust sources
are potential emission sources of metal HAP's, but not organic HAP's or
HCl and Cl2. Therefore, the five listed sources will be covered by
the proposed regulation.
C. Selection of Basis and Level for the Proposed Standards for New and
Existing Sources
Section 112(d)(3)(B) of the Act requires that the EPA set standards
no less stringent than ``the average emission limitation achieved by
the best performing 5 sources'' for categories with fewer than 30
sources. Floor levels of control were determined for each of the
affected source types under consideration for regulation. Source types
are process sources, process fugitive sources, and fugitive dust
sources. For process fugitive sources and fugitive dust sources, which
are similar in character and emissions potential across all secondary
lead smelters, the entire population of secondary lead smelters was
considered in determining MACT floor levels of control. For process
sources, specifically smelting furnaces, smelters were differentiated
and divided into configurations based on the smelting furnace types
used at individual smelters. This was done because smelting furnaces
differ substantially, based on configuration, in both emissions
potential (mix and amounts) and achievable control levels for organic
HAP's. Section 112(d)(1) of the Act gives the Administrator the
authority to distinguish among classes, types, and sizes of sources
within a category when establishing standards.
Because the secondary lead smelter category comprises fewer than 30
sources, the floor level of control selected for existing sources is
based on the median level of control achieved by the best-performing
five sources. That is, the floor level of control reflects the control
technology in use by the source positioned third (the median) among the
best-performing five. The median was selected as the MACT floor, rather
than the mean, because the MACT floor is based on the control
technology used and the mean cannot be determined. The floor for new
sources reflects the control technology in use by the best-controlled
source in the category. Emission limits were then selected based on the
performance continuously achievable by the proposed MACT technology.
1. Selection of MACT for Process Sources
Separate MACT floors were determined for the following smelting
furnace configurations: (1) Collocated reverberatory and blast
furnaces, (2) blast furnaces not collocated with a reverberatory
furnace, (3) reverberatory or rotary furnaces not collocated with a
blast furnace, and (4) electric furnaces. Only smelters with a similar
furnace configuration were used to establish the MACT floor level of
control for new and existing furnaces within each configuration. The
four configurations were selected based on differences in potential
emissions and control options among the configurations.
With one exception--the blast-furnace-only configuration--the MACT
floor level of control was the only option considered because no
options more stringent than the MACT floor are known. For the blast-
furnace-only configuration, two options--the floor and one more
stringent than the floor--were considered.
The emission reductions and cost impacts of the proposed MACT floor
and more stringent options are presented in more detail in chapters 5
and 6 of the BID, respectively.
a. Reverberatory/Blast Furnace Configuration. Control measures
currently in use to control furnace emissions at collocated
reverberatory/blast furnace facilities are combinations of
afterburners, gas stream blending, baghouses, wet scrubbers, and
fluxing additions.
Afterburners used to control only blast furnace emissions are
capable of achieving about 90-percent control of organic HAP's, THC,
and CO. Gas stream blending consists of mixing blast furnace gases with
hotter and larger volume reverberatory furnace gases in a chamber for
incineration. Gas stream blending provides more cost-effective control
of organic HAP's than do afterburners by utilizing the large volume of
hot (greater than 1,000 deg.C) exhaust produced by the reverberatory
furnace. Greater than 99-percent control of THC (the surrogate for
organic HAP's) and 98-percent control of CO have been demonstrated
(Docket No. A-92-43, Item No. II-A-3).
Baghouses are used to control PM and lead. Properly operated and
maintained, baghouses are capable of achieving greater than 99-percent
control of PM and about 98-percent control of lead and other metal HAP
compounds (Docket No. A-92-43, Items II-A-1, II-A-2, II-A-3). Wet
scrubbers, primarily in place to control SO2, are capable of
providing 99-percent control of HCl/C2 (Docket No. A-92-43, Item
No. II-A-3). The addition of soda ash or limestone fluxing agents to
the furnace feed to enhance the removal of chlorides through slagging
can achieve HCl/Cl2 control equivalent to that of wet scrubbing
(Docket No. A-92-43, Items II-A-1, II-A-2).
Nine smelters operate reverberatory/blast configurations. The best-
controlled source and best-performing five sources all blend gas
streams to control organic HAP emissions, use baghouses to control
metal HAP emissions, and either scrub or flux to control HCl/Cl2
emissions. Consequently, the combination of these controls constitutes
MACT floors for both new sources and existing sources.
Because there are no control options available for consideration
more stringent than the MACT floor controls for new or existing
sources, the technological basis selected for the proposed standards
for collocated reverberatory/blast furnaces is gas stream blending to
control organic HAP's, a baghouse to control metal HAP's, and a
scrubber or flux addition to control HCl/Cl2.
Under this selection of MACT for existing sources, six smelters
would have to upgrade their air pollution controls to some degree to
meet the proposed MACT. Physical upgrades would include the retrofit of
additional ductwork at five smelters to blend the blast and
reverberatory furnace gas stream to achieve incineration of organic
HAP's in the blast furnace emissions. Other upgrades required at four
smelters include the addition of fluxing agents to the reverberatory
furnace feed for HCl/Cl2 control.
Total estimated capital costs for upgrades at the smelters
requiring additional ductwork would be about $330,000. The costs for
purchasing additional fluxing agents were included as annual costs
rather than capital costs. Total annualized costs for all six impacted
smelters would be about $120,000--$40,000 for capital recovery and
about $80,000 for the purchase of fluxing agents (soda ash or
limestone) at four smelters that do not have SO2 scrubbers.
Installing the proposed MACT floor controls at smelters with
reverberatory/blast furnaces would reduce organic HAP emissions by 640
Mg/yr (700 tpy) and HCl/Cl2 emissions by 360 Mg/yr (400 tpy).
Emissions of THC and CO would also be reduced by about 2,500 Mg/yr
(2,800 tpy) and 47,000 Mg/yr (52,000 tpy), respectively. All of these
smelters currently have baghouses, so there would be no reduction in
metal HAP emissions from process sources and no associated cost
impacts.
b. Blast Furnace Configuration. Control measures currently in use
to control furnace emissions at blast furnace-only facilities include
afterburners, baghouses, wet scrubbers, and fluxing. Although installed
primarily for the combustion of CO, afterburners also provide varying
degrees of control for organic HAP's. The most important variable in
afterburner performance, that is, the ability to combust and destroy
organics, is temperature, although residence time and turbulence are
also important. Temperature, however, is the most important variable,
with higher levels of destruction achieved at higher temperatures.
The operating temperature of the best-performing afterburner in
this furnace configuration is 870 deg.C (1,600 deg.F) (Docket No. A-
92-43, Item No. II-D-4), which represents an estimated 98-percent
organic HAP control (Docket No. A-92-43, Item II-B-31). The average
temperature of the five best-performing afterburners operating at the
highest temperatures is 700 deg.C (1,300 deg.F), which represents an
estimated 84-percent organic HAP control. Baghouses, wet scrubbers, and
fluxing provide the same levels of control for metal HAP's (98 percent)
and HCl/Cl2 (99 percent) for blast furnaces as for collocated
reverberatory/blast furnaces.
The blast furnace-only configuration encompasses 13 blast furnaces
at 8 smelters. The best-controlled blast furnace is controlled by an
afterburner at 870 deg.C (1,600 deg.F) to control organic HAP's and a
baghouse to control metal HAP's, and performs fluxing with soda ash or
limestone or operates an SO2 scrubber to control HCl/Cl2
emissions. The combination of these controls constitutes the proposed
MACT for new sources.
Seven blast furnaces are controlled by an afterburner to control
organic HAP's and a baghouse to control metal HAP's, and perform
fluxing or use a scrubber to control HCl/Cl2. The average
temperature of the five afterburners operated at the highest
temperatures is 700 deg.C (1,300 deg.F). The proposed MACT floor for
existing sources is, therefore, an afterburner operated at 700 deg.C
(1,300 deg.F), a baghouse, and fluxing.
To comply with a standard based on the MACT floor for existing
sources, five smelters would have to upgrade their air pollution
controls. Physical upgrades would include the installation of
afterburners at three smelters. Other upgrades required at four
smelters would be increased afterburner temperature, which would
require an increase in natural gas consumption. Total estimated capital
costs for upgrades at the smelters requiring new afterburners would be
about $810,000. Total annualized costs would be $590,000--$120,000 for
capital recovery and $470,000 for increased fuel costs and other
operating expenses to operate all afterburners at 700 deg.C (1,300
deg.F).
Installing the proposed MACT floor controls at all existing blast
furnace facilities would reduce organic HAP emissions by 580 Mg/yr (640
tpy). All blast furnace facilities currently have baghouses and perform
fluxing, so there would be no reductions in metal HAP or HCl/Cl2
emissions and no associated cost impacts. Emissions of THC and CO would
also be reduced by about 2,700 Mg/yr (3,000 tpy) and 32,000 Mg/yr
(35,000 tpy), respectively.
There is one control option more stringent than the controls in the
floor for existing sources. That option is to raise the afterburner
temperature from 700 to 870 deg.C (1,300 to 1,600 deg.F)--effectively
adopting the same controls for existing sources as the new source MACT.
The EPA evaluated the incremental impacts of selecting an afterburner
at 870 deg.C (1,600 deg.F) as the technological basis for controlling
existing sources. Physical upgrades would include the installation of
new afterburners at seven smelters, and other upgrades would include
increased natural gas consumption at all but one smelter.
Total capital and annualized costs for upgrades at blast furnace
smelters would nearly triple under the more stringent option. Estimated
total capital costs would increase by $1,700,000 to $2,300,000 (at 870
deg.C) relative to the floor level of control, and annualized costs
would increase by $1,100,000 to $1,700,000. The increased costs would
lead to an increase in adverse economic impacts. Under the more
stringent option, 7 blast furnace smelters would be significantly
impacted, compared to 5 smelters under the MACT floor option. The two
additional smelters that are significantly impacted are operating
smelters.
Under the more stringent option, organic HAP emissions at blast
furnace smelters would decrease an additional 110 Mg/yr (120 tpy),
compared to an emissions reduction of 580 Mg/yr (640 tpy) under a
standard based on the floor. Emissions of THC and CO would decrease by
an additional 500 Mg/yr (550 tpy) and 21,000 Mg/yr (23,000 tpy),
respectively, compared to initial reductions of 2,700 Mg/yr and 32,000
Mg/yr under a standard based on the floor. The incremental cost-
effectiveness of organic HAP reductions would be $10,000/Mg ($9,100/
ton) under the more stringent option.
In light of the cost and economic impacts and the HAP reductions
achievable, the EPA has concluded (subject to comment) that adoption of
this more stringent (above the MACT floor) option as the basis for
standards for existing blast furnace smelters is unreasonable.
Therefore, the technological basis for the proposed standards for
existing blast furnaces is an afterburner at 700 deg.C (1,300 deg.F),
a baghouse, and fluxing or a scrubber.
The EPA is aware, however, that this proposal permits organic HAP
emissions at the eight facilities with blast furnace-only
configurations to remain significantly higher than the organic HAP
emissions resulting from other configurations. Further, the EPA
recognizes that additional reductions are technically feasible at these
locations if the afterburner temperatures are raised. The EPA requests
comment on how consideration of the differential impacts and
environmental justice should be incorporated in the final MACT
determination. The EPA specifically requests comment on the decision to
establish proposed standards at the MACT floor for the blast furnace-
only smelting configuration.
c. Rotary and Reverberatory Furnace Configurations. Control
measures currently in use to control furnace emissions at rotary
furnace and reverberatory furnace facilities are baghouses, wet
scrubbers, and the addition of fluxing agents. Baghouses and wet
scrubbers provide the same levels of control for metal HAP's (98
percent) and HCl/Cl2 (99 percent), respectively, as with other
furnace configurations. Soda ash and limestone are added to all rotary
furnaces and some reverberatory furnaces as fluxing agents, providing
HCl/Cl2 control equivalent to that of scrubbing.
The high exhaust temperature maintained in rotary and reverberatory
furnaces (greater than 1,000 deg.C) ensures nearly complete
destruction of any organic HAP's present. Consequently, no additional
control for organic HAP's is necessary.
Six smelters operate either rotary or reverberatory furnace
configurations. The best-controlled furnace and best-performing five
furnaces use a baghouse to control metal HAP's and a scrubber or
fluxing to control HCl/Cl2. Consequently, the combination of these
controls constitutes the MACT floors for both new source and existing
source. Because there are no control options available for
consideration more stringent than the controls in the floors for new or
existing sources, the technological basis selected for the proposed
standards for rotary and reverberatory furnaces is a baghouse for
controlling metal HAP's and a scrubber or flux addition for controlling
HCl/Cl2.
Under this selection of MACT for new and existing sources, two
smelters would have to upgrade their air pollution controls to some
degree by increasing the amount of fluxing agents added to their
furnaces. No capital costs would be incurred; total annualized costs
would be $76,000 for the additional fluxing agents at the two smelters.
Hydrochloric acid and Cl2 emissions would be reduced by about 350
Mg/yr (390 tpy). There would be no reduction in metal HAP or organic
HAP emissions and no associated cost impacts. All six smelters
operating this configuration currently have baghouses for PM, lead, and
other metals control. Add-on controls for organic HAP emissions are
unnecessary because neither furnace type emits organic HAP's.
d. Electric Furnace Configuration. There is currently only one
electric furnace in use in the secondary lead smelting source category.
It is used to process slag generated at three reverberatory furnace-
only smelters. The furnace is equipped with a baghouse to control PM
and lead emissions. Neither organic HAP's nor HCl/Cl2 are emitted
from this furnace because it processes only slag that is relatively
free of organic matter and available chlorine. Consequently, a baghouse
constitutes the floor for both new source and existing source MACT for
controlling metal HAP's. Because there are no available control options
more stringent than a baghouse, the proposed MACT for new and existing
sources is a baghouse. Because this furnace already has a baghouse, no
upgrades in air pollution controls are needed and there would be no
emission reductions or cost impacts associated with the proposed
standard.
2. Selection of MACT for Process Fugitive Sources
Process fugitive sources are similar in emissions characteristics
and control technology across all secondary lead smelters, regardless
of smelting furnace configuration. Therefore, there was no need to
distinguish among process furnace configurations when developing the
standards for process fugitive sources. The entire population of
secondary lead smelters was used in determining MACT floor levels of
control for new and existing sources.
The four types of process fugitive sources being regulated are
smelting furnace charging and tapping locations, flue dust
agglomerating furnaces, refining kettles, and dryers. All of these are
sources of metal HAP's and are typically controlled by hoods ventilated
to baghouses.
The proposed equipment specifications for the design and operation
of capture hooding and ventilation for process fugitive sources are
adapted from the Occupational Safety and Health Administration's
(OSHA's) ``Cooperative Assessment Program Manual for the Secondary Lead
Smelter Industry'' (Docket No. A-92-43, Item No. II-I-16). The OSHA
manual specifies that process fugitive sources should be controlled by
an enclosure-type hood that is ventilated so that a minimum face
velocity is achieved. Face velocity is the velocity at which air is
drawn into a hood and, along with hood type, is a primary factor in
hood capture efficiency. The minimum recommended face velocity varies
by source type, but is generally about 110 m/min (350 fpm). These
controls represent state-of-the-art ventilation practices to protect
workers by promoting effective capture and ventilation of process
fugitive emissions.
The OSHA manual was developed in 1983 through a cooperative effort
by government, industry, and labor in response to the occupational
health standard for lead (29 CFR 1910.1025), which requires that
employers in the secondary lead smelting industry implement controls to
reduce employee exposure to lead. The manual was prepared to assist
employers and employees in identifying and implementing the best
controls that were recognized as technologically feasible.
Based on observations at operating secondary lead smelters, the EPA
believes that the capture and ventilation systems installed and
operated at secondary lead smelters are designed and operated in
accordance with the specifications contained in the OSHA cooperative
assessment program manual. These controls consequently establish the
MACT floor. Therefore, the EPA is proposing to incorporate these
specifications into the proposed MACT for new and existing process
fugitive sources.
a. Smelting Furnace Charging and Tapping. Smelting furnace charging
and tapping are sources of metal HAP's. Blast furnace charging can also
be a source of organic HAP's. With one exception, all furnace charging
and lead tapping and slag tapping locations on 44 smelting furnaces are
enclosed in a hood and captured emissions are ventilated to a baghouse
for the control of metal HAP's. One blast furnace has no hooding or
ventilation on the charging chute. Consequently, the MACT floor for
existing sources is hooding and ventilation to a baghouse for the
control of metal HAP's. There are no control options above the MACT
floor, so the floor is the proposed MACT for both existing and new
sources. The OSHA manual recommends an enclosure-type hood with a
minimum face velocity of 110 m/min (350 fpm) for these emission points.
The manual also recommends a similar hood for the transition piece on
rotary furnaces.
The proposed MACT to control organic HAP emissions from blast
furnace charging is a hood over the charging chute with a ventilation
flow rate that is properly balanced against the primary exhaust flow
rate from the furnace. The two flow rates are balanced to minimize the
escape of primary exhausts and organic HAP's to the furnace charging
hood.
b. Agglomerating Furnaces. Agglomerating furnaces are sources of
metal HAP's. They are used at nine smelters and all are hooded and
ventilated to a baghouse. Therefore, the MACT floor for existing
sources is a hood with ventilation to a baghouse. There are no control
options above the MACT floor, so the MACT floor is the basis for the
proposed MACT for both new and existing sources. The OSHA manual
recommends an enclosure-type hood with a minimum face velocity of 110
m/min (350 fpm).
c. Refining Kettles. Refining kettles are sources of metal HAP's.
There are about 170 refining kettles and they are hooded and ventilated
to baghouses at all but three smelters; three smelters use wet
scrubbers instead of baghouses. Baghouses typically offer greater
control of metal HAP's than wet scrubbers. Therefore, the MACT floor
for existing sources is a hood and ventilation to a baghouse. There are
no control options above the MACT floor, so the MACT floor is the basis
for the proposed MACT for both new and existing sources. The OSHA
manual recommends enclosure-type hoods with minimum face velocities of
75 m/min (250 fpm) and flow rates of at least 60 m\3\/min per m\2\ (200
acfm/ft\2\) of the surface area of the kettle's contents.
d. Dryers. Dryers are sources of metal HAP's. They are currently in
use at six smelters to remove moisture from materials just prior to
charging them to reverberatory smelting furnaces. Each dryer has a
transition piece between the dryer cylinder and the furnace feed chute.
These transition pieces on all dryers are hooded and ventilated to a
baghouse. The MACT floor for both existing and new dryers is,
therefore, hoods over the transition pieces with ventilation to a
baghouse. There are no control options above the MACT floor, so the
MACT floor is the basis for the proposed MACT for both new and existing
sources.
The OSHA manual does not contain recommendations for dryers, but
the transition piece on a dryer is analogous to the transition piece on
a rotary smelting furnace, for which the manual recommends an
enclosure-type hood with a face velocity of at least 110 m/min (350
fpm). The proposed MACT includes these specifications.
3. Impacts of Proposed Standards for Process Fugitive Sources
There are no controls more stringent than those established by the
MACT floor described above for process fugitive sources. Therefore, the
EPA is proposing standards for process fugitive sources that correspond
to the MACT floor.
One smelter would be required to upgrade its process fugitive
controls by adding a hood over its blast furnace charging chute. The
estimated capital and annualized costs to enclose and ventilate this
one source would be $47,000 and $4,400, respectively. The estimated
pollutant reduction would be 26 Mg/yr (29 tpy) of metal HAP's.
Another smelter would be required to balance existing ventilation
air at the blast furnace charging chute to preclude the inadvertent
collection of process gases that contain organic HAP's. The potential
emission reductions at the one smelter at which organic HAP process
emissions were detected in the charging hood exhaust air would be about
50 Mg/yr (55 tpy).
The EPA has no data on the performance of the wet scrubbers being
used to control the refining kettle emissions at three smelters. The
MACT floor for refining kettles is hooding and ventilation to a
baghouse, and baghouses are generally more efficient than scrubbers in
controlling metal HAP's. However, refining kettles are very similar to
scrap melting operations at battery manufacturing facilities. Data from
the latter that are controlled by wet scrubbers indicate that refining
kettles controlled by wet scrubbers should be able to achieve a lead
limit that is based on the performance of a baghouse (Docket No. A-92-
43, Item No. II-A-8). Therefore, it should not be necessary to replace
the existing wet scrubbers with baghouses and there should be no
associated cost impacts.
4. Selection of MACT for Fugitive Dust Sources
Fugitive dust sources are similar in emissions characteristics and
control technology for all smelters, regardless of smelting furnace
configuration. Therefore, there was no need to distinguish among
furnace configurations when developing the standards for fugitive dust
sources. The entire population of 23 secondary lead smelters was used
to determine the MACT floors for new and existing fugitive dust
sources.
The four areas of fugitive dust sources being regulated are battery
breaking areas, furnace and refining and casting areas, materials
storage and handling areas, and plant roadways.
Controls for fugitive dust sources include: (1) Paving all areas
subject to vehicle traffic to facilitate the removal of accumulated
dust, (2) periodic cleaning of all paved areas to remove deposited dust
and prevent its re-entrainment or transfer to other areas by vehicle
traffic, (3) vehicle washes at exits from materials storage and
handling areas to prevent carry-out of metal HAP-bearing residues and
dust, (4) wetting or use of chemical surfactants, binding agents, or
sealers on storage piles coupled with partial or total enclosures to
limit wind erosion and the generation of dust associated with materials
storage and handling, and (5) ventilating total enclosures, where used,
to a baghouse or equivalent device to capture airborne dust.
Total enclosure of a fugitive dust source and ventilation of the
enclosure to a control device may at first appear to be the most
effective means of controlling fugitive dust emissions. However, the
EPA has determined from observations of operating smelters and a
technical analysis of fugitive dust control measures applicable to this
source category that partial enclosures with appropriate wetting and
pavement cleaning cost much less and are equally effective in
controlling fugitive dust emissions when coupled with monitoring and
recordkeeping to ensure these activities are performed (Docket No. A-
92-43, Item No. II-B-28).
It should be noted that existing Clean Water Act effluent
limitation guidelines already provide discharge allowances, based on
technology-based controls, for pollutants in the wastewater generated
from facility wash down and truck washing. This proposed regulation
should not require any amendments to those standards. (See 40 CFR 421,
subpart M).
a. Battery Breaking Area. At least nine smelters control fugitive
dust emissions from the battery breaking area. Controls include partial
or total enclosures, vacuum or powerwashing systems, and the wetting of
storage piles. Therefore, these controls are the MACT floor for
existing sources. Because there exists no more stringent controls that
are demonstrated for the battery breaking area, these floor level
controls are the proposed MACT for existing sources and are also the
proposed MACT for new sources. An equivalent alternative technology is
to totally enclose the area and ventilate the entire building or
enclosure volume to a baghouse.
b. Furnace and Lead Refining and Casting Areas. At least 12
smelters either totally enclose the furnace and lead refining and
casting areas and ventilate the enclosure to a baghouse, or partially
enclose this area on at least three sides and vacuum or powerwash the
pavement. The remaining smelters use some, but not all, of these
techniques. Therefore, partial enclosure coupled with pavement cleaning
(vacuuming or powerwashing) or total enclosure ventilated to a baghouse
is the MACT floor for existing sources. Because no more stringent
controls are available, these floor level controls are the proposed
MACT for existing sources and are also the proposed MACT for new
sources.
c. Materials Storage and Handling Areas. At least 12 smelters have
paved the materials storage and handling areas, operate vehicle washes
at exits from these areas, and either totally enclose the area and
ventilate the enclosure to a baghouse or partially enclose the storage
piles and use wetting or other dust suppression techniques on the
storage piles. The remaining smelters use some, but not all, of these
techniques. Therefore, vehicle washes, paving, and either partial
enclosure coupled with wet suppression or total enclosure and a
baghouse is the MACT floor for existing sources. Because no more
stringent controls are available, these floor level controls are the
proposed MACT for existing sources and also the proposed MACT for new
sources.
d. Roadways. At least 16 smelters have paved their roadways and
periodically clean the pavement by vacuuming or powerwashing.
Therefore, these controls are the MACT floor for existing sources.
Because no more stringent controls are available, these floor level
controls are the proposed MACT for existing sources and also the
proposed MACT for new sources.
5. Impacts of Proposed Standards for Fugitive Dust Sources
The EPA is proposing that the MACT floors should serve as the basis
of the proposed standards for fugitive dust sources because there are
no available control technologies more stringent than the MACT floors.
Each smelter would be required to develop an SOP manual that describes
how it will use MACT controls to limit fugitive dust emissions and
operate according to the manual at all times.
Thirteen smelters would be required to upgrade their fugitive dust
controls and practices to meet the MACT level of control in the
proposed standards. Four smelters would need to purchase mobile vacuum
systems and allocate additional labor hours to operate them. Nine
smelters that already operate vacuums would need to increase the
operation of the vacuums to clean additional areas not currently
vacuumed or begin implementing some form of dust suppression practices
in the materials storage area.
The capital costs of adopting the proposed standards would be about
$190,000 for the purchase of vacuums at four smelters. The total annual
cost would be $110,000, which includes the annualized cost of the new
vacuums, operating labor for additional vacuuming, and the cost of
additional water (including treatment) for wet suppression. The
estimated emission reductions would be 23 Mg/yr (25 tpy) of metal
HAP's. The dust collected by the additional vacuum sweepers and other
fugitive dust controls would be recycled back into the smelting furnace
to recover the lead content. Therefore, there would be no significant
costs incurred for the management of the captured fugitive dust.
D. Selection of the Format for the Proposed Standards
Several formats were considered to implement the control techniques
selected as the basis for the proposed standards. These include
emission standards in a variety of format options, as well as design,
equipment, work practice, and operational standards. Section 112(d) of
the Act requires the Administrator to prescribe emission standards for
HAP control unless, in the Administrator's judgement, it is not
feasible to prescribe or enforce emission standards.
Section 112(h) defines two conditions under which it is not
feasible to prescribe or enforce emission standards:
(1) If the HAP cannot be emitted through a conveyance device
designed and constructed to emit or capture the HAP, or
(2) if the application of measurement methodology to a particular
class of sources is not practicable because of technological or
economic limitations. If it is not feasible to prescribe or enforce
emission standards, then the Administrator may instead promulgate
equipment, work practice, design, or operational standards, or a
combination thereof.
Format options for numerical emission standards or limits include
mass concentration (mass per unit volume), volume concentration (volume
per unit volume), mass emission rate (mass per unit time), process
emission rate (mass per unit of production or other process parameter),
and percent reduction.
1. Process Emission Sources
The EPA is proposing numerical emission standards, expressed as
mass or volume concentrations, for lead, THC, and HCl/Cl2
emissions from smelting furnaces. As noted in section II.D of this
preamble, lead and THC have been selected as surrogates for metal HAP's
and organic HAP's, respectively.
Baghouses constitute the technological basis for the MACT standards
proposed to limit metal HAP emissions from smelting furnaces. Because
of the physical mechanism by which baghouses operate, they
characteristically achieve a constant outlet concentration independent
of the inlet concentration or loading. Tempering air is introduced
before the baghouse at some smelters to cool furnace process emissions
and control baghouse temperature, but this dilution prior to the
baghouse does not affect outlet concentrations or baghouse performance.
Dilution with ambient air between the control device and an emission
monitoring or testing point is prohibited under section 63.4 of the
General Provisions.
Other format options considered included mass rate (kg/hr), a
production-based emission rate (kg/Mg of furnace charge), and percent
reduction. The EPA is not proposing the mass emission rate format (kg/
hr) because it cannot account for differences in actual emission rates
between different size smelting furnaces. The production-based emission
rate format is not proposed because production rate is difficult to
measure over short periods and the mass emission rate from a baghouse
may not correlate well with production rate during an emissions test.
The EPA is not proposing the percent reduction format because baghouses
are constant outlet devices, causing removal efficiency to vary with
inlet loading. In addition, this format would require simultaneous
testing at inlet and outlet locations, which would subject smelters to
unnecessary additional testing costs. Consequently, the EPA is
proposing a concentration limit for lead reflecting performance of a
properly operated baghouse.
The format the EPA is proposing for the THC emission standard is
concentration expressed in ppmv as propane, corrected to a constant
CO2 concentration. The correction to a constant CO2
concentration accounts for any dilution due to blending with process
fugitive emission streams prior to discharge to the atmosphere.
Alternative formats that were evaluated but not selected were mass
emission rate, production-based emission rate, and percent reduction.
The format of the proposed HCl/Cl2 standard is concentration
expressed as mg/dscm and corrected to a constant CO2 concentration
to account for dilution from combined process fugitive streams. Format
options examined but not selected for the HCl/Cl2 emission
standard include mass emission rate, production based emission rate,
and percent reduction.
For both the THC and HCl/Cl2 emission standards, the kg/hr
mass emission format was not proposed because it does not account
appropriately for size differences among smelting furnaces. The EPA is
not proposing the production-based emission rate format because of the
difficulty in establishing relationships between emissions and
production or process parameters during the short time period of an
emissions test. The percent reduction format is not proposed because
there is often no suitable inlet location for testing. In addition,
even if a suitable test location were available, this format requires
simultaneous inlet and outlet testing, which would subject smelters to
unnecessary additional testing costs.
The measured THC and HCl/Cl2 concentrations would be corrected
to a constant CO2 concentration of 4 percent to account for
dilution from tempering air or from combined process fugitive emission
sources. The measured THC or HCl/Cl2 concentration would be
multiplied by a correction factor determined by dividing 4 percent
CO2 by the CO2 measured during the compliance test. If the
measured CO2 concentration is less than 0.4 percent, then a
maximum correction factor of 10 would be used. A cap on the correction
factor was selected because the relation between the correction factor
and the measured CO2 concentration is non-linear and the
correction factor becomes unreasonably high at a CO2 concentration
below 0.4 percent. Furthermore, the proposed method for measuring
CO2 (EPA reference method 3B) is only accurate to within 0.2
percent CO2.
A cap on the correction factor will not bias compliance
calculations towards less stringent enforcement of the THC or HCl/
Cl2 emission standards. It is unlikely, because of the economic
cost of moving such a large volume of air, that any smelter would
attempt to dilute a process emission stream more than 10 times above
the level needed for normal gas stream conditioning.
2. Process Fugitive Sources
The proposed standards for process fugitive emissions would
require: (1) Proper capture of process fugitive emissions, and (2)
control or destruction of the captured emissions. Equipment
specifications (i.e., requirements for hoods with specified face
velocities) are proposed to ensure that emissions from process fugitive
sources are effectively captured and conveyed into a duct that can be
directed to a control device.
Numerical emission limits are being proposed to judge the
performance of the control device. A numerical emission limit (mg/dscm)
for lead compounds, as a surrogate for metal HAP's, is proposed for the
control device that collects the captured process fugitive emissions
(e.g., the sanitary baghouse). A mass rate (kg/hr) THC emission limit,
as a surrogate for organic HAP's, is being proposed for emissions from
blast furnace charging. A concentration THC limit was considered but is
inappropriate because of the variability among smelters in the quantity
of ventilation air applied at furnace charging locations and the
frequent mixing of furnace charging air with ventilation air from other
process fugitive sources, such as furnace tapping locations and
refining kettles.
The THC limit on blast furnace charging would apply only if the
charging process fugitive emissions are discharged through a separate
stack from the process emissions. The facility operator would not need
to demonstrate compliance with the THC emission standard for process
fugitive charging emissions if two conditions exist: (1) The
ventilation air from the hood and the process exhaust gases are
combined and discharged through a common stack, and (2) compliance with
the THC emission limit for process sources is determined downstream
from the point at which the charging ventilation air and process source
exhaust are combined. In this case, compliance with the THC limit for
process sources would be sufficient to confirm that process emissions
are not escaping into the blast furnace charging hood and that all
organic HAP emissions are being properly controlled.
3. Fugitive Dust Sources
Work practice standards are being proposed to control fugitive dust
sources, as allowed under section 112(h) of the Act. Because of their
nature, fugitive dust emissions can not be captured and subsequently
discharged through a stack, vent, or other conveyance. Consequently,
the use of conventional stack sampling methods are not practical or
feasible. The proposed work practice standards would also require the
development of a site-specific SOP manual that describes the steps that
would be taken to limit fugitive dust emissions from all affected
sources. The controls included in the SOP manual must be equivalent to
those specified in the proposed regulation.
E. Selection of Emission Limits and Equipment and Work Practice
Standards for New and Existing Sources
The proposed emission limits for lead, THC, and HCl/Cl2 are
based on emissions data collected by the EPA primarily through an
emission source testing program conducted at several well-controlled
secondary lead smelters. The purpose of the testing program was to
evaluate the performance of candidate MACT systems and to establish
appropriate and corresponding limits.
Prior to the EPA testing program, compliance test data and
emissions data from previous EPA studies of the secondary lead smelting
industry were collected and reviewed. These data were mostly for
criteria pollutants (PM, lead, and SO2) and included insufficient
data for metal HAP's, organic HAP's, or HCl/Cl2 to accurately
estimate baseline emissions and to establish emission limits.
Therefore, the EPA testing program was initiated to collect additional
data on HAP emissions and on surrogates that are strongly correlated
with HAP emissions.
The EPA testing was conducted at six facilities: a collocated
reverberatory/blast furnace facility, a rotary furnace-only facility, a
reverberatory furnace-only facility, and three blast furnace
facilities. These facilities were selected for testing because they
were representative of other facilities with similar furnace
configurations and because each facility had controls for organic
HAP's, metal HAP's, and HCl/Cl2 that represented the MACT floor
controls.
Complete results of the testing program and their analyses are
summarized in chapter 3 and appendix A of the BID. The derivation of
the proposed emission limits for process and process fugitive sources
is described in more detail in Docket No. A-92-43, Item No. II-B-32.
1. Process Sources
Emission limits for process sources were developed from EPA test
data for lead and THC (surrogates for metal HAP's and organic HAP's,
respectively) and for HCl/Cl2.
a. Lead Emission Limit. The proposed lead emission limit was
selected primarily on the basis of the results of EPA-sponsored tests
of smelting furnaces controlled by well-maintained and well-operated
baghouses. The EPA tested three baghouses used to control furnace
exhausts from a blast furnace, a combined reverberatory/blast furnace,
and a rotary furnace. The baghouse on the blast furnace also treated
ventilation air from furnace charging and lead and slag tapping. Three
sample runs using EPA reference method 12 were conducted at the outlet
of each baghouse to quantify lead emissions.
The average lead concentration from each baghouse ranged from 0.60
to 0.70 mg/dscm (0.00026 to 0.00031 gr/dscf). The average lead
concentration for all three baghouses tested (total of nine sample
runs) was 0.66 mg/dscm (0.00029 gr/dscf). Individual runs ranged from
0.28 mg/dscm to 1.03 mg/dscm.
A statistical analysis of the variability in the process baghouse
data was performed. The analysis inherently accounts for variability in
emissions from well-operated and well-maintained baghouses as well as
measurement variability. At a 95-percent confidence level, lead
emissions measured during subsequent tests of the same baghouses could
be as high as 1.3 mg/dscm (0.00057 gr/dscf) with no changes in baghouse
operation or maintenance. This suggests that the proposed lead emission
limit should be no lower than 1.3 mg/dscm.
Compliance test data collected from other operating smelters were
also examined. These data, consisting of 23 individual compliance
tests, show lead emissions from process baghouses ranging from 0.04 to
4.7 mg/dscm (0.00002 to 0.0021 gr/dscf) and suggest that the lead
emission limit should be higher than 1.3 mg/dscm.
Most of the data are distributed continuously at concentrations
less than or equal to 1.6 mg/dscm. The emissions of 1.6 mg/dscm were
measured at a new smelter just after it began operating in 1992. Close
examination of the data greater than 1.6 mg/dscm and available
documentation provided the following comments. Lead emissions of 2.3
mg/dscm were measured in 1988 at a smelter that has since upgraded its
air pollution control systems. The other emissions data greater than
2.3 mg/dscm were measured at smelters that are not currently operating.
The operation and maintenance quality of the baghouses at these latter
smelters cannot, therefore, be determined.
These compliance data indicate that the lead emission limit should
be greater than 1.6 mg/dscm but less than 2.3 mg/dscm. Based on this
information, the EPA selected an emission limit of 2.0 mg/dscm (0.00087
gr/dscf) as a reasonable value between 1.6 and 2.3 mg/dscm.
A complete and detailed presentation of the baghouse test data,
both EPA-collected and industry-supplied, is included in chapter 3 and
appendix A of the BID. The analysis performed in selecting the proposed
lead emission limit is described in Docket No. A-92-43, Item No. II-B-
32.
The compliance data available to the EPA show several smelters with
lead emissions substantially lower than 2.0 mg/dscm. These data may
lead to the conclusion that the MACT floor emission limit (based on the
average emission limitation achieved by the best-performing five
sources) should also be substantially lower than 2.0 mg/dscm. However,
it should be kept in mind that these compliance data, like the EPA test
data, were collected over a brief time period, i.e., three 1-hour runs.
Therefore, these data represent only a ``snapshot'' of the performance
of each source and do not necessarily represent an emission level that
can be continuously achieved on a long-term basis by the MACT floor
control technology.
There are variations in emissions over time that cannot be
attributed to variation in any particular furnace or control device
operating or maintenance parameter. This is demonstrated, for example,
by the variation in the measurements observed over the three runs
during a single emissions test. The EPA took this variation in
emissions into account when developing the proposed emission limit of
2.0 mg/dscm by examining all of the data that are available for
smelting furnaces controlled by well-operated and well-maintained
baghouses. The proposed 2.0 mg/dscm emission limit represents the
average of the five best-performing sources adjusted for variability
and it is continuously achievable on a long-term basis by a smelter
controlled by a well-operated and well-maintained baghouse.
b. THC Emission Limits. The EPA measured controlled THC
concentrations at the following smelting furnace configurations with
corresponding MACT controls: (1) A reverberatory/blast furnace
combination controlled by gas stream blending with a combined exhaust
temperature of 930 deg.C (1,700 deg.F); (2) a blast furnace
controlled by an afterburner operating at 700 deg.C (1,300 deg.F);
(3) a rotary furnace with no add-on organic HAP controls; and (4) a
reverberatory furnace with no add-on organic HAP controls.
The THC concentration at each smelter was measured using EPA
reference method 25A and expressed as an equivalent concentration of
propane. The average CO2 concentration was also measured as part
of the gas stream analysis using EPA reference method 3B (40 CFR part
60, appendix A). The results of this testing program are presented in
more detail in chapter 3 and appendix A of the BID. The methodology for
the selection of the THC limits is described in more detail in Docket
No. A-92-43, Item No. II-B-32.
The reverberatory/blast furnace configuration tested by the EPA was
controlled by blending the blast and reverberatory furnace gases and
then venting the combined stream to an afterburner. The average
temperature of the combined stream at the afterburner inlet was 780
deg.C (1,430 deg.F) and the average afterburner outlet temperature was
940 deg.C (1,720 deg.F). The temperature range of the afterburner
outlet was 900 deg.C to 980 deg.C (1,650 deg.F to 1,800 deg.F). The
residence time of the afterburner was 2.5 seconds. In this
configuration, the fuel input to the afterburner was minimal and most
of the afterburner temperature increase was probably due to the fuel
value of the organic compounds in the blast furnace exhaust.
At the reverberatory/blast furnace smelter, the controlled THC
measurements were made over three 3-hour sampling runs. The average THC
concentrations for the three runs were 3.0 ppmv, 5.1 ppmv, and 20 ppmv
at 4 percent CO2. The average concentration for all three runs was
9.4 ppmv at 4 percent CO2. The variation observed in THC
concentrations could not be correlated with any variation in the
smelting furnaces or combustion conditions during the tests and,
therefore, appears to be normal for a well-controlled reverberatory/
blast furnace configuration. The THC emissions limit selected for
collocated reverberatory/blast furnaces is 20 ppmv (as propane
corrected to 4 percent CO2), which is the highest THC
concentration obtained during the individual 3-hour runs. The EPA
selected the highest run as the proposed THC limit to account for
normal variation in THC emissions.
The blast furnace tested by the EPA was controlled by an
afterburner with an average operating temperature of 700 deg.C (1,300
deg.F), although during the tests the temperature varied between 680
and 730 deg.C (1,250 and 1,350 deg.F), with a few short-term spikes
to 790 deg.C (1,450 deg.F). The retention time of the afterburner was
2.5 seconds.
At the blast furnace-only smelter, the controlled THC emissions
were measured over two 3-hour runs. The average THC concentration in
the first run was 300 ppmv (as propane, corrected to 4 percent
CO2) and the average THC concentration during the second run was
360 ppmv. The average afterburner temperature during both runs was 700
deg.C (1,300 deg.F). The 20-percent difference in THC concentration
between the two runs could not be attributed to any other smelting
furnace or afterburner operating parameter, so the difference is
expected to represent normal variation in THC emissions from a well-
controlled blast furnace. Based on these tests, the EPA is proposing a
THC emissions limit for blast furnace facilities of 360 ppmv (as
propane, corrected to 4 percent CO2), which is the higher
concentration from the two 3-hour runs. The EPA selected the higher
concentration to account for the normal variability in THC emissions
from a blast furnace controlled by an afterburner operating at 700
deg.C (1,300 deg.F).
No data are available for the THC concentration from a blast
furnace controlled by an afterburner operating at 870 deg.C (1,600
deg.F), the proposed MACT for new blast furnaces. However, previous EPA
studies have demonstrated that afterburners operating at 870 deg.C and
a minimum residence time of 0.75 seconds are capable of achieving a 98-
percent destruction efficiency for vent streams with organic
concentrations greater than 2,000 ppmv as carbon (about 700 ppmv as
propane) (Docket No. A-92-43, Item No. II-B-31). Based on a typical
uncontrolled level for THC of 3,500 ppmv as propane, the predicted THC
concentration from a blast furnace controlled by an afterburner
operating at 870 deg.C (1600 deg.F) is 70 ppmv, at 4 percent
CO2. Therefore, the EPA is proposing a THC limit for new blast
furnace facilities of 70 ppmv (as propane, corrected to 4 percent
CO2).
The exhaust temperature from rotary and reverberatory furnaces are
comparable to the afterburner outlet temperature of the reverberatory/
blast furnace configuration (940 deg.C [1720 deg.F]), so there is
nearly complete combustion of organic compounds within the furnace
itself and no add-on organic HAP controls are needed. Rotary furnaces
are operated in batches lasting from 15 to 24 hours in length. During
charging, the furnace temperature is reduced and there are brief (1-
hour) periods when the THC level may reach as high as 1,500 ppmv. The
THC level drops quickly, however, to less than 10 ppmv when charging is
completed and the furnace is brought to normal operating temperature.
Reverberatory furnaces are operated at a constant temperature so there
are no peaks in organic emissions associated with charging.
None of the rotary furnaces in use at secondary lead smelters have
add-on controls for organics or CO. At the rotary furnace smelter
tested by the EPA, the THC concentration at the furnace outlet was
measured over six complete batch cycles. Each batch cycle lasted from
15 to 24 hours. The THC concentration averaged over the length of each
batch cycle ranged from 35 to 170 ppmv as propane, corrected to 4
percent CO2. The organic HAP emission rate from the rotary
smelting furnace was only about 0.5 kg/hr (1 lb/hr), compared to about
3 and 9 kg/hr (7 and 20 lb/hr) of uncontrolled organic HAP emissions
from the reverberatory/blast and blast furnaces tested by the EPA,
respectively.
The proposed MACT for new and existing rotary furnaces is no add-on
control for organic HAP's, which is consistent with the MACT floor for
these furnace types. For this reason, and because of the low organic
HAP emissions potential from rotary furnaces, no THC emissions limit is
being proposed for rotary furnaces.
At the reverberatory furnace smelter tested by the EPA, the THC
concentration was measured at the furnace outlet over one 5-hour run
and three 1-hour runs. The average THC concentration, as propane, for
each run ranged from 9 to 11 ppmv, at 4 percent CO2. The average
THC concentration was lower than for rotary furnaces because
reverberatory furnaces are operated on a continuous basis and the
furnace temperature is not lowered during charging. No add-on or
process modification organic HAP controls are in use for this furnace
type, and the proposed MACT for new and existing reverberatory furnaces
is no add-on control. Therefore, no THC emissions limit is being
proposed for reverberatory furnaces.
No THC or organic HAP emissions data are available for the electric
smelting furnace. However, this furnace processes only slag that is
essentially free of organic material, and, therefore, is not likely to
be a source of organic HAP emissions. This presumption is confirmed by
CO emissions (which are correlated with organic HAP emissions) that are
similar to CO emissions from other furnace types that also have low
organic HAP emissions (Docket No. A-92-43, Item II-I-22).
The EPA is not proposing organic HAP or THC standards for rotary,
reverberatory, and electric smelting furnaces because of the low
organic HAP emission potential and because the MACT floor for organic
HAP controls is no control for these configurations. Moreover,
efficient production of lead in these furnace types requires operating
and exhaust temperatures that result in low organic HAP and THC
emissions. Relatively low emissions, therefore, should be ensured even
in the absence of an emissions standard or a monitoring requirement.
c. HCl and Chlorine Emission Limits. The EPA measured HCl and
Cl2 emissions at the following smelting furnace configurations
with corresponding MACT controls: (1) A reverberatory/blast furnace
configuration controlled by the addition of soda ash to the blast
furnace and by a wet SO2 scrubber on the combined blast and
reverberatory furnace exhausts; (2) a blast furnace controlled by the
addition of soda ash to the furnace and a wet SO2 scrubber; and
(3) a rotary furnace controlled by the addition of soda ash to the
furnace and a wet SO2 scrubber. The facilities were selected for
testing because they were representative of other facilities with
similar furnace configurations and because each smelter was fitted with
a wet SO2 scrubber. At the time the testing program was initiated,
wet SO2 scrubbers were the only HCl/Cl2 controls being
evaluated. The use of fluxing to control HCl/Cl2 emissions was
developed as a result of the EPA testing program.
Emissions of HCl and Cl2 were measured ahead of and after the
scrubber at each smelter in three 1-hour sample runs using EPA
reference method 26A. The average CO2 concentration was also
measured as part of the gas stream analysis using EPA reference method
3B (40 CFR part 60 appendix A).
At the blast furnace and rotary furnace smelters, the total HCl/
Cl2 concentrations and emission rates measured ahead of the
scrubber were less than 1 mg/dscm (0.0004 gr/dscf) and 0.05 kg/hr (0.1
lb/hr), respectively. At these low levels, no detectable incremental
control was observed across the scrubber at either facility.
The reverberatory/blast furnace had a much higher total HCl/
Cl2 concentration and emission rate ahead of the scrubber than
either the blast and rotary furnaces: 273 mg/dscm (0.119 gr/dscf) and
12.5 kg/hr (27.6 lb/hr), respectively. About 98 percent of these
emissions were HCl and 2 percent were Cl2. The scrubber was
measured to be 99.8-percent effective in reducing total HCl/Cl2
emissions, and the controlled emissions were less than 1 mg/dscm
(0.0004 gr/dscf) and 0.05 kg/hr (0.1 lb/hr).
The EPA believes that the very low uncontrolled HCl emissions
observed are due to the use of soda ash and limestone as fluxing agents
in the rotary and blast furnaces. Both smelters reported that soda ash
or limestone were added primarily to enhance the reduction of lead
compounds to lead metal. An analysis performed by the EPA indicates
that these fluxing agents will also bind chloride ions in the feed
material as NaCl or CaCl2 salts so that the chlorides are removed
in the slag rather than being emitted as HCl or Cl2. No fluxing
agents were added to the reverberatory furnace in the reverberatory/
blast configuration tested, and uncontrolled emissions of HCl recorded
were substantially higher than those recorded at the blast and rotary
furnaces tested with fluxing. However, the wet scrubber was effective
in reducing the HCl/Cl2 emissions from the reverberatory/blast
furnace to the same level as observed from the blast and rotary
furnaces using fluxing agents.
All three of these furnace types charge the smelting furnace with
battery scrap which contains PVC battery plate separators. These
separators, when burned, are believed to be the source of the chlorides
observed. These chlorides may be removed from the furnace in two ways,
either in the form of HCl and Cl2 in the exhaust gas or they may
be bound in the slag and subsequently removed. At both the blast and
rotary furnaces, soda ash or limestone are normally charged with the
battery scrap. These compounds react with the available chlorides to
form salts (NaCl or CaCl2), which are stable at typical furnace
temperatures. These salts are then removed from the furnace during
slagging. At the reverberatory/blast furnace combination, neither soda
ash nor limestone was charged to the furnace with the battery scrap.
Subsequently the chlorides are eliminated from the furnace as HCl and
Cl2 emissions.
Tests were also conducted at a reverberatory furnace at which soda
ash is charged to the furnace. These tests indicate that substantial
reductions in HCl emissions are possible (greater than 90 percent) by
adding soda ash to this type of furnace. Other facilities operating
this type of furnace also add soda ash or limestone to the furnace
feed, but the EPA has no emissions data on these furnaces. Because
these other facilities normally charge these fluxing agents to the
furnaces, it is believed that the addition of these fluxing agents will
have no detrimental effect on the final lead product.
A related method called de-sulfurizing also appears effective in
eliminating emissions of HCl/Cl2. The chlorides are eliminated
from the furnace in the slag using the same chemical mechanism
previously described. In this process, the battery paste and flue dust
are reacted with soda ash to remove the sulfur from the feedstock. In
this process, unreacted soda ash remains with the resulting paste and
is charged into the furnace. Data indicate that resulting HCl emissions
are very low, less than 1.5 mg/dscm (Docket No. A-92-43, Item Nos. II-
D-18 and II-D-21).
If a facility chooses not to add these fluxing agents to the
furnace for process-related reasons, wet scrubbers are capable of
achieving the same emission rates for HCl/Cl2.
It is also important to note that the EPA believes the potential
for HCl emissions from this source category will be diminishing over
the next several years. As stated earlier, the source of chlorides in
the furnace is the PVC separators. Most battery manufacturers are
phasing out the use of PVC separators in favor of other materials
(Docket No. A-92-43, Item No. II-I-11).
Based on the EPA test results and technical analysis, the EPA is
proposing an HCl/Cl2 limit of 15 mg/dscm, corrected to 4 percent
CO2, for all smelting furnace configurations except the electric
smelting furnace. The EPA is proposing an HCl/Cl2 limit of 15 mg/
dscm rather than 1 mg/dscm, which was the emission concentration
measured during testing, because EPA reference method 26A has a
possible negative bias below an HCl concentration of 30 mg/dscm (59 FR
19306-19323). The margin between 1 mg/dscm and 15 mg/dscm was selected
to account for this potential bias. The CO2 correction factor is
to account for dilution if the process emissions at a facility are
combined with process fugitive emissions before the point at which
compliance with the HCl/Cl2 limit is determined.
No data are available for HCl or Cl2 emissions from the
electric smelting furnace. However, this furnace processes only
reverberatory furnace slag in which chlorides are present in the form
of NaCl or CaCl2 and there is a very low potential for HCl and
Cl2 emissions. Therefore, the EPA is not proposing an HCl or
Cl2 limit for this configuration.
2. Process Fugitive Sources
Equipment specifications are being proposed for process fugitive
emission capture systems. Emission limits for lead emissions as a
surrogate for metal HAP's are being proposed for control devices that
handle captured process fugitive emissions. Emission limits for THC
emissions as a surrogate for organic HAP's are being proposed for
control devices that handle the gas streams from blast furnace charging
capture systems.
a. Equipment Specifications. The proposed equipment specifications
for process fugitive emission capture systems were selected on the
basis of observations at operating smelters and the recommendations
contained in the OSHA Cooperative Assessment Program Manual for the
Secondary Lead Smelter Industry. The proposed equipment specifications
are described in more detail under the selection of MACT for process
fugitive sources in section VI.C of this preamble.
Observations made during EPA visits to operating smelters indicated
that nearly all process fugitive emission sources at all the smelters
visited are controlled by enclosure-type hoods consistent with those
recommended in the OSHA manual. All of these hoods were ventilated to
baghouses or wet scrubbers. Face velocities measured with a hand-held
anemometer at one smelter were greater than the minimum face velocities
recommended in the OSHA Manual. (Docket No. A-92-43, Item No. II-B-34).
b. Lead Emission Limit. The proposed lead emission limit was
selected on the basis of the results of EPA-sponsored tests of process
fugitive sources controlled by well-maintained and well-operated
baghouses.
The EPA determined baghouse performance for the control of process
fugitive metal HAP emissions by measuring baghouse outlet lead
concentrations using EPA reference method 12. The EPA tested six
baghouses controlling process fugitive sources at three smelters. One
baghouse controlled the refining kettles at a blast furnace smelter.
Another baghouse controlled the refining kettles and furnace charging
and tapping at a rotary furnace smelter. The remaining four baghouses
controlled the process fugitive emissions and building ventilation
sources at a reverberatory/blast furnace smelter. The average of three
runs was used to characterize the performance of each baghouse.
The average lead concentration from each baghouse ranged from 0.33
to 1.82 mg/dscm (0.00015 to 0.00080 gr/dscf). The average lead
concentration for all six baghouses tested was 0.83 mg/dscm (0.00036
gr/dscf). The baghouse with the highest lead emission rate appeared to
be well operated and well maintained, although removal efficiency was
substantially lower because the inlet grain loading was also lower than
for the other process fugitive baghouses.
A statistical comparison of the average emission concentrations
indicate that there is no significant difference in the controlled lead
emissions from the process fugitive baghouses compared to the process
baghouses at the 5 percent probability level. A statistical analysis of
the normal variability in the process fugitive baghouse data (excluding
the baghouse with the lowest efficiency) predicted at the 95-percent
confidence level that lead emissions measured during subsequent tests
of the same baghouses could be as high as 2.0 mg/dscm (0.00087 gr/dscf)
with no changes in baghouse operation or maintenance. Compliance test
data provided to the EPA by smelter operators show lead emissions from
process fugitive baghouses ranging from 0.02 to 1.1 mg/dscm (0.00001 to
0.00048 gr/dscf), indicating that all smelters could achieve a lead
emission level of 2.0 mg/dscm. This emission level also accommodates
the baghouse with the 1.82 mg/dscm outlet concentration measured by the
EPA. Based on the outcome of the EPA testing program, the EPA has
selected a proposed lead emissions limit of 2.0 mg/dscm (0.00087 gr/
dscf) for process fugitive sources.
The EPA baghouse data are presented in chapter 3 and appendix A of
the BID. The analysis performed in selecting the proposed lead emission
limit is detailed in Docket No. A-92-43, Item No. II-B-32.
c. THC Emission Limit. The proposed THC emissions limit for process
fugitive emissions from blast furnace charging was selected on the
basis of the results of EPA-sponsored tests of the charging system at
two blast furnaces. Each blast furnace charging chute was enclosed in a
hood. On the first furnace, the chute was also fitted with a door that
opened during charging. The flow rate of each hood was balanced against
the flow rate of the primary furnace exhaust to minimize the escape of
primary exhaust gases to the charging hood.
The THC emission rate was measured in the duct leading from the
charging hood using EPA reference method 25A. Each test consisted of
two 3-hour runs. The THC emission rates measured during each run of the
first test were 0.026 kg/hr (0.058 lb/hr) and 0.035 kg/hr (0.077 lb/hr)
(Docket No. A-92-43, Item No. II-A-5). The THC emission rates measured
during each run of the second test were 0.11 kg/hr (0.24 lb/hr) and
0.20 kg/hr (0.44 kg/hr) (Docket No. A-92-43, Item II-A-6). The average
THC emission rate for all four runs was 0.090 kg/hr (0.20 lb/hr). The
THC emissions were substantially lower from the furnace fitted with the
door, but it could not be confirmed that the difference was due to the
door or simply normal variation in emissions from well-controlled
charging ventilation systems. The THC emission rate from the higher of
the two sources tested was less than 1 percent of the THC emissions
from the blast furnace charging chute at which the potential emission
problem was first detected.
Based on these test results, the EPA is proposing a THC emissions
limit for blast furnace charging process fugitive emissions of 0.20 kg/
hr (0.44 lb/hr), which was the highest THC value obtained during the
test runs and was selected to account for normal variation in THC
emissions. The EPA THC data from blast furnace charging are presented
in chapter 3 and appendix A of the BID.
3. Fugitive Dust Sources
The proposed standard requires an SOP manual for the control of
fugitive dust emissions and also establishes a lead emissions limit for
building and enclosure ventilation systems.
a. SOP Manual. The EPA is proposing that each smelter develop an
SOP manual that would describe the controls and work practices that
would be implemented to control fugitive dust emissions. These control
and work practices would be equivalent to those specified in the
proposed regulation. The EPA selected the controls in the proposed
regulation on the basis of observations made during visits to smelters
that had already implemented fugitive dust controls equivalent to the
proposed MACT and on the basis of a technical analysis of the
effectiveness of different control options (Docket No. A-92-43, Item
No. II-B-28).
The use of a site-specific SOP manual is being proposed, rather
than a list of required work practices, because there are several
equivalent control options available for fugitive dust. The flexibility
of the SOP approach is needed because the best control option for a
particular smelter would be determined by the physical layout of the
smelter and the control measures that are already in place. These two
factors vary greatly among smelters.
b. Lead Emissions Limit. The EPA is proposing a lead emissions
limit of 2.0 mg/dscm (0.00087 gr/dscf) for ventilation systems for
buildings that enclose fugitive dust sources, such as the materials
storage and handling area or the furnace and refining and casting
areas. This limit was selected on the basis of controlled lead
emissions from the process fugitive baghouses (which also controlled
some building ventilation emissions) measured during the EPA testing
program and is the same limit that was selected for process and process
fugitive sources.
F. Reconstruction Considerations
Section 112(a) of the Act defines a new source as a stationary
source, the construction or reconstruction of which is commenced after
the proposal date of a relevant regulation. An existing source is
defined as any stationary source other than a new source.
Reconstructed sources are considered to be new sources.
Reconstruction means the replacement of components of an existing
source to such an extent that: (1) The fixed capital cost of the new
components exceeds 50 percent of the fixed capital cost that would be
required to construct a comparable new source, and (2) it is
technologically and economically feasible for the reconstructed source
to meet all relevant promulgated standards for new sources.
Some changes can be made at secondary lead smelters that may be
deemed reconstructions under section 63.5 of the General Provisions.
However, the proposed standards for secondary lead smelters are the
same for both existing and new sources except in the case of the THC
emission limit for blast furnace-only configurations. As a result, the
designation as a ``reconstruction'' has limited practical significance.
If a change to an existing blast furnace is determined to constitute a
reconstruction, then that furnace would be subject to the proposed THC
limit for new blast furnaces, which is more stringent than the limit
for existing blast furnaces. In order to meet the more stringent THC
limit, a reconstructed blast furnace would probably need to install a
new afterburner that could reach a temperature of 870 deg.C (1,600
deg.F), based on the proposed MACT for new blast furnaces.
G. Selection of Compliance Dates
The proposed regulation would require owners or operators of
existing secondary lead smelters to achieve compliance with the
proposed standards within 24 months of promulgation. This schedule
would allow the affected sources the time necessary to modify existing
processes and control equipment; design, fabricate, and install new
control equipment as needed; develop and implement the SOP for
equipment and work practice standards; and complete installation of all
required continuous monitoring systems.
The proposed 2-year period for existing sources to achieve
compliance with the proposed standard is based on the estimated time
needed for a blast furnace facility to have a new afterburner designed,
fabricated, installed, and tested. The installation of a new
afterburner is the most significant upgrade anticipated under the
proposed standard. The EPA believes that a 2-year period is realistic
and practical to accomplish these required tasks. The proposed standard
is also consistent with compliance deadlines allowed by section 112(i)
of the Act, which allows existing sources up to 3 years to achieve
compliance.
Owners or operators of new secondary lead smelters would be
required to achieve compliance upon startup or promulgation of this
NESHAP (whichever is later) and must perform compliance testing within
6 months of startup or promulgation, pursuant to sections 63.6 and 63.7
of the General Provisions.
H. Selection of Emission Test Methods and Schedule
Testing requirements are being proposed for lead, THC, and HCl/
Cl2 from process, process fugitive, and fugitive dust sources.
1. Process Sources
Lead emissions from process emission control devices would be
measured using EPA reference method 12, THC emissions would be measured
using EPA reference method 25A, and HCl/Cl2 emissions would be
measured using EPA reference method 26A. For all of these tests, EPA
reference method 1 would be used to determine the number and locations
of sampling points, method 2 would be used to determine stack gas
velocity and volumetric flow rate, method 3 would be used for flue gas
analysis, and method 4 would be used to determine the volume percent
moisture content in the stack gas. For the measurement of THC and HCl/
Cl2, the Single Point Integrated Sampling and Analytical Procedure
of method 3B would be used to measure CO2 in order to correct for
excess air or dilution.
Each test would consist of three runs conducted under
representative operating conditions. The average of the three runs
would be used to determine compliance. The test methods selected above
were used by the EPA to collect the data upon which the proposed
emission limits are based.
The proposed standard would require initial tests of lead emissions
from all sources and annual compliance tests for process fugitive
sources and building ventilation systems. Annual tests of the latter
two sources must be performed because compliance with the lead emission
standard cannot be continuously monitored. The proposed standard would
also require initial compliance tests for THC and HCl/Cl2 and then
monitoring to demonstrate continuous compliance. Following the initial
THC compliance test, no annual compliance test would be required if the
facility maintains or exceeds the minimum afterburner temperature
established during the initial compliance test. Following the initial
HCl compliance test, no annual compliance test would be required if the
facility maintains the required level of fluxing, scrubber parameters,
or SO2 concentration established during the initial compliance
test or operates and maintains an HCl monitor.
2. Process Fugitive Sources
An annual compliance test for lead using the same methods as for
process sources would be required for process fugitive control devices.
If a facility is subject to the THC emission limit for blast furnace
charging, then an initial test would be required that would use the
same THC measurement methods as for process sources.
Compliance with the face velocity and flow rate requirements for
enclosure hoods over process fugitive emission sources would be
determined by measuring the flow in the duct leading from the source
and by measuring the area of the openings in the hood and the area of
the refining kettle, if appropriate. Volumetric flow rate in the duct
would be measured using EPA reference method 2. Hood face area or
kettle surface area would be measured directly.
There are no EPA reference methods for directly measuring the face
velocity of a hood. The use of a hand-held anemometer was evaluated,
but this technique is not as accurate or as precise as calculating the
face velocity from the measured volumetric flow rate and face area.
3. Fugitive Dust Sources
Compliance with the lead emission standard for building ventilation
emission points would be determined using the same methods as for
process sources. Compliance would be determined through an annual test
of each emission point, except in the case of emissions from identical
control devices that are discharged through separate stacks.
If a facility has two or more identical control devices for
building ventilation, then each would be required to undergo an initial
compliance test. Subsequent compliance tests, however, could be
alternated or rotated among the identical control devices so that not
all of them would be tested every year. However, at least one device
would be tested each year and each device would be tested at least once
every 5 years. This provision assumes that the maintenance of identical
units would be similar as a result of the baghouse inspection and
logging procedures in the monitoring requirements of the proposed
standard. In addition, smelters would only be allowed to alternate
compliance testing as long as they demonstrate compliance with the
baghouse inspection and logging provisions of the proposed monitoring
requirements. This provision is being proposed to reduce unnecessary
testing costs. This provision would not apply to control devices
receiving emissions from process or process fugitive sources.
I. Selection of Proposed Enhanced Monitoring Requirements
Section 114(a) of the Act, as amended under section 702(b) of title
VII of the 1990 amendments, requires enhanced monitoring and the
submission of periodic compliance certifications for all major
stationary sources. Compliance certifications shall include information
on the methods used for determining compliance status and statements as
to whether compliance was determined on an intermittent or continuous
basis.
The enhanced monitoring requirements proposed herein were
determined by examining the hierarchy of monitoring options available
for specific processes, pollutants, and control equipment. This
hierarchy may range from monitoring continuously the emissions of a
specific pollutant or pollutant class to the continuous monitoring of a
related process or control device parameter. Each option was evaluated
relative to its technical feasibility, cost, ease of implementation,
and relevance to its underlying process emission limit or control
device.
The proposed standards for secondary lead smelters contain
monitoring requirements for process sources, process fugitive sources,
and fugitive dust sources. The proposed standards require either
pollutant monitoring directly through the use of a CEM, parameter
monitoring that indicates proper operation and maintenance of a control
device, or recordkeeping to ensure that specific work practices are
being followed.
1. Process Sources
Monitoring requirements are being proposed to ensure control of
metal HAP, organic HAP, and HCl/Cl2 emissions from process
sources.
a. Metal HAP's. The EPA is proposing that each process baghouse be
monitored with a COM and that a site-specific opacity limit be
established for each process emission point. The site-specific opacity
limit for an affected baghouse would be equal to the maximum 6-minute
opacity reading recorded by a COM during the initial compliance test
for lead emissions, plus 2 percent opacity to allow for normal drift in
the output from the COM. Exceedance of the site-specific opacity limit
would constitute a violation of the standard for lead emissions.
The proposed MACT for the control of metal HAP's is a baghouse of
the design now used in the industry that is operated and maintained
optimally on a continuous basis. The facilities at which baghouses were
assessed in the EPA testing program had comprehensive, periodic
inspection and maintenance programs to ensure proper operation of the
baghouses. However, these inspection and maintenance programs are
relatively costly to implement, and offer no explicit assurance that
the emission limitations in the standards are being achieved on a
continuous basis.
Emissions from a baghouse change with time as a result of
incidental or periodic upsets (e.g., torn bags) and normal wear of
baghouse components. Inspection and maintenance programs aid in
protecting against slow, continual degradation of baghouse performance
but do not ensure continuous optimal operation. Although inspection and
maintenance may indicate a baghouse is functioning normally, there is
no assurance that an established emission limitation is being achieved.
Furthermore, these programs, if sufficiently comprehensive to ensure
the baghouse is performing optimally on a continuous basis, are labor-
intensive and, as noted, quite costly.
The EPA estimates that with a good inspection and maintenance
program a baghouse may still emit, on average, an emission stream with
an opacity of 5 or 10 percent. Several theoretical and experimental
studies have been performed to quantify the relationship between the PM
concentration in an emissions stream and the opacity of the stream.
From such a relationship developed at a secondary brass/lead smelter,
it is estimated that gases in a stack with a 1.5 meter diameter
exhibiting an opacity of 10 percent could contain as much as 80 mg/dscm
PM. Given that the PM discharged from process baghouses at secondary
lead smelters typically contains about 25 percent lead, the lead
concentration of the baghouse discharge corresponding to 10 percent
opacity would be 20 mg/dscm. This is 10 times the pollutant
concentration of the proposed standard (Docket No. A-92-43, Item No.
II-A-35).
In contrast, the use of COM's offer a timely, sensitive and direct
indication of increased emissions. They give an immediate indication of
an occurrence, which provides for timely action that will minimize the
duration and, therefore, the emissions, of an upset. They can also
address the long-term gradual deterioration of performance of a
baghouse.
In addition, COM's are cost-effective. A typical, generally
available monitor with auxiliaries costs about $37,300 to install and
about $16,500 to operate annually. Proper usage of a COM can ensure
that the gases emitted from a baghouse exhibit less than 2 percent
opacity on average over a year (Docket No. A-92-43, Item No. II-B-34.
The approximate cost-effectiveness of reducing the average opacity from
10 percent to 2 percent through the use of a COM is $2,100 per ton of
lead or $525 per ton of PM.
The EPA invites comments on the reasonableness of incorporating
this strategy for COM into the final standard promulgated for this
source category.
b. Organic HAP's. The EPA is proposing two monitoring options that
smelter operators may pursue. Continuous monitoring systems are
available for THC, but the operating and maintenance costs of existing
systems may be prohibitive for many sources in this category.
Alternatively, operators may continuously monitor afterburner or
exhaust stream temperature, which correlates strongly with THC
emissions, after conducting an initial performance test to demonstrate
compliance with the THC standard.
Under the second option, THC and temperature would have to be
measured simultaneously for three runs lasting 1 hour each during the
initial THC compliance test. The average THC concentration and
temperature would be determined for the total sampling period.
Compliance with the THC standard would be determined on the basis of
the average THC concentration. The minimum allowable afterburner or
exhaust temperature would be determined on the basis of the average
temperature during the total sampling period. To remain in compliance,
the owner or operator could not allow the average temperature for any
3-hour period to fall more than 28 deg.C (50 deg.F) below the average
measured during the initial THC compliance test. Allowing the average
temperature to fall below this level would constitute a violation of
the emissions standard.
The proposed allowable temperature range of 28 deg.C (50 deg.F)
for the afterburner or combined reverberatory/blast exhaust streams is
based on temperature data collected during the organic HAP and THC
testing performed by the EPA. During the test of the blast furnace, the
3-hour average temperature of the afterburner varied over a range of 32
deg.C (59 deg.F). During the test of the reverberatory/blast furnace
configuration, the 3-hour average temperature of the combined exhaust
stream varied over a range of 29 deg.C (52 deg.F). The proposed 28
deg.C (50 deg.F) allowable temperature range is consistent with the
range allowed in the monitoring requirements for sources controlled by
afterburners in other Federal standards (40 CFR part 60, subparts EE,
MM, SS, TT, WW, BBB, DDD, FFF, III, NNN, QQQ, SSS, and VVV).
Another THC compliance test would be required if the operator
desires to establish a lower afterburner temperature. Owners or
operators also have the option of monitoring THC using a CEM instead of
temperature.
c. HCl and Chlorine. Continuous emission monitors are available for
HCl, but they have not been used in this industry. Furthermore, the
estimated capital and annual costs of these CEM's for the entire
industry would be $2,900,000 and $1,400,000, respectively. The cost of
requiring an HCl CEM would double the capital and annual cost impacts
of the proposed standards and would increase the number of facilities
that are significantly impacted. Other, less costly monitoring options
are available, so the EPA has determined that an HCl CEM should not be
required and several alternative monitoring options are being included
in the proposed standard. However, these alternatives allow the use of
an HCl CEM to fulfill the monitoring requirements for HCl/Cl2, if
an operator chooses to use one.
Where SO2 scrubbers are used, continuous emission monitoring
for SO2 can be used as an indicator of scrubber performance.
Alternatively, scrubber parameters, including sorbent injection rate
and pH, can also be monitored as indicators of scrubber performance.
Where fluxing with soda ash or limestone is used to preclude HCl/
Cl2 emissions, monitoring the use of these fluxing agents can
ensure that sufficient quantities are being added to control emissions.
The EPA is therefore proposing four alternative monitoring options
for control of HCl/Cl2: (1) manual monitoring of the addition of
soda ash and limestone, (2) instrument monitoring of scrubber
parameters, (3) CEM for SO2, or (4) CEM for HCl. Each of these
alternatives is described below.
Option 1. Owners or operators could monitor the amounts of soda ash
and limestone added to the smelting furnace and the total amount of
charge material added during the 8-hour shift in which the initial HCl/
Cl2 compliance test was performed. This ratio of soda ash and
limestone to total charge material would establish a minimum ratio that
would be maintained thereafter. A new HCl/Cl2 compliance test
would be required if the operator wanted to alter the amount or type of
fluxing agent to be used in the future. Continued compliance would be
determined on the basis of the ratio of soda ash and limestone to total
charge material added to the furnace during each 8-hour shift
thereafter. Failure to maintain the same ratio would constitute a
violation of the HCl/Cl2 standard.
Option 2. The owner or operator of a facility that has a scrubber
to control HCl and Cl2 could record the scrubber liquid injection
rate and pH every 15 minutes during the initial HCl/Cl2 compliance
test, which consists of three 1-hour runs. The average of these
recorded values for pH and media injection rate would be used to
establish minimum operating parameters for the scrubber that must be
maintained thereafter. Failure to maintain the minimum scrubber media
injection rate or minimum inlet pH would constitute a violation of the
HCl/Cl2 standard.
The media injection rate would be recorded every 15 minutes after
the HCl compliance test and could be no less than 70 percent of the
average injection rate demonstrated during the initial HCl compliance
test. No data were collected during the EPA tests on the variability of
SO2 scrubber media injection rates. The proposed 30-percent
allowable drop in media injection rate is adopted from the range
allowed in the monitoring requirements in other Federal standards (40
CFR part 60, subparts LL, OOO, and PPP) for sources controlled by wet
scrubbers.
The standards in subparts LL, OOO, and PPP are for control of PM
sources, not acid gases. Therefore, the EPA is also considering
allowing no drop in liquid injection rate, but has not included that
requirement in the proposed regulation. The EPA solicits comment on the
appropriateness of allowing a 30-percent drop in liquid injection rate.
The scrubber media inlet pH would also be recorded every 15 minutes
and the 3-hour average could be no more than 1.0 pH points below the
average inlet pH demonstrated during the initial HCl/Cl2
compliance test. The allowable pH range of 1.0 for the scrubber media
inlet pH is based on data collected during the HCl/Cl2 testing
performed by the EPA. During the EPA test of the blast furnace, the 3-
hour average pH of the sorbent at the SO2 scrubber inlet varied
from 7.7 to 8.3, a range of 0.6. At the reverberatory/blast furnace
tested, the pH of the sorbent at the SO2 scrubber outlet showed a
similar pH range. An allowable pH range of 1.0, rather than 0.6, is
being proposed because HCl and Cl2 are absorbed more easily than
SO2, and control of HCl and Cl2 would not vary significantly
over a scrubber sorbent pH range of 1.0.
Option 3. The owner or operator of a facility that operates an
SO2 scrubber could record the SO2 concentration every 15
minutes during the initial HCl/Cl2 compliance test. The average of
these recorded values for SO2 concentration would be used to
establish a 3-hour average maximum SO2 concentration that could
not be exceeded thereafter. The SO2 concentration would be
recorded every 15 minutes and the average for any 3-hour period could
be no more than 200 ppmv above the average SO2 concentration
measured during the initial HCl/Cl2 compliance test. A 3-hour
average SO2 concentration exceeding the maximum SO2
concentration would constitute a violation of the HCl/Cl2
standard.
The allowable SO2 range is based on data collected during the
HCl/Cl2 testing performed by the EPA. During the test of the
reverberatory/blast furnace configuration, the 3-hour average SO2
concentration, as recorded by the facility's SO2 CEM, ranged from
37 ppmv to 195 ppmv. During the test of the blast furnace, the 3-hour
average SO2 concentration ranged from 0 ppmv to 50 ppmv. An
allowable range of 200 ppmv above the average SO2 concentration
measured during the initial HCl/Cl2 compliance test is being
proposed to reflect the range of SO2 concentrations measured and
the fact that HCl and Cl2 are absorbed more easily than SO2.
Option 4. The owner or operator could also install, operate, and
maintain an HCl CMS and demonstrate compliance with an initial HCl/
Cl2 compliance test and by meeting all of the requirements for
CMS's found in the General Provisions. The CO2 concentration
needed to correct for dilution would be determined during the initial
HCl/Cl2 compliance test and would not need to be continuously
monitored. To remain in compliance, the HCl concentration measured by
the CMS and corrected to 4 percent CO2 must remain below an HCl
limit of 15 mg/dscm.
The HCl limit of 15 mg/dscm for enhanced monitoring was based on
the results of the EPA-sponsored HCl/Cl2 testing. These tests
indicated that about 98 percent of the chlorine was emitted as HCl.
2. Process Fugitive Sources
The proposed MACT for control of metal HAP emissions from process
fugitive sources is an enclosure-type hood ventilated to a baghouse.
When these hoods are in place and the smelter has demonstrated
compliance with the proposed face velocity and flow rate requirements,
no further monitoring of capture efficiency would be necessary.
Similarly, the proposed MACT for control of organic HAP emissions from
blast furnace charging is proper balance between the blast furnace
charging and primary exhaust ventilation systems. No monitoring of
blast furnace charging would be necessary after compliance has been
demonstrated with the THC limit for blast furnace charging.
As noted previously, no CMS's are available for lead. In addition,
a COM cannot be used to monitor process fugitive baghouse performance
because the opacity of uncontrolled process fugitive emissions is too
low to indicate a control device failure. Therefore, the proposed
standard would require daily, weekly, and monthly inspection of process
fugitive baghouses and would require monitoring the pressure drop and
water flow rate of PM scrubbers. Scrubbers are used instead of
baghouses at some smelters to control process fugitive sources.
The majority of smelters already perform regular inspections of
baghouses and monitor scrubber operating parameters as part of normal
baghouse and scrubber operation and maintenance. These monitoring
requirements would ensure that the control devices are being operated
and maintained in a manner consistent with good air pollution control
practices. These monitoring requirements are being proposed as
separately enforceable standards. However, a violation of the proposed
monitoring requirements could not be used to indicate a violation of
the proposed lead emissions limit for process fugitive sources.
Therefore, the proposed standard would also require an annual
compliance test of lead emissions.
The proposed baghouse inspection program is the only monitoring
option available for process fugitive sources controlled by baghouses
at secondary lead smelters. This proposed requirement is not intended
to serve as a model of monitoring requirements for other source
categories of particulate or HAP emissions controlled by baghouses.
3. Fugitive Dust Sources
Monitoring of compliance with the work practice controls for
fugitive dust sources specified in each smelter's SOP manual would be
accomplished through recordkeeping requirements that would also be
specified in the SOP.
A COM is not applicable to the building and enclosure ventilation
emission points that are subject to the lead emissions limit. The
proposed standard, therefore, would require a baghouse inspection
program and an annual compliance test of lead emissions for the same
reasons as those described above for process fugitive baghouses.
J. Selection of Notification Requirements
Owners or operators of secondary lead smelters would be required to
comply with all of the notification requirements under section 63.9 of
the General Provisions. An owner or operator would be required to
submit the initial notification, notifications of performance tests,
notification of CMS performance evaluations, and the notification of
compliance status. Information submitted in these notifications would
confirm that the source is subject to the standards and establish the
source's compliance status.
Each operator of a smelter would also be required to submit the
fugitive dust control SOP manual to the Administrator or his or her
authorized representative, along with a notification that the smelter
is seeking review and approval of the manual. Operators of existing
smelters would be required to submit the manual no later than 180 days
before the compliance date for existing smelters. Operators of new
smelters would be required to submit the manual no later than 180 days
before startup of the new smelter but no sooner than the effective date
of the proposed standard.
The notification of compliance status would list the results of any
performance tests and opacity measurements, methods used for
determining continuous compliance, descriptions of the air pollutant
control equipment and methods applied at each affected emission point,
and a statement as to whether the source is in compliance with all
relevant standards and provisions of this subpart. The proposed
regulation would waive the requirement that the smelter perform an
analysis demonstrating whether the smelter is a major source or area
source since the regulation would apply equally to all smelters. The
compliance notification would also certify that the facility has
completed an SOP manual for the control of fugitive dust emissions and
that the SOP manual has been approved by the Administrator.
K. Selection of Recordkeeping and Reporting Requirements
The recordkeeping and reporting requirements of the General
Provisions for 40 CFR part 63 would apply to secondary lead smelters
unless specifically superseded in this part.
1. Recordkeeping
Consistent with the General Provisions of part 63 and with the
operating permit rules in part 70, promulgated under title V of the
Act, records required by this part would be retained for at least 5
years. Each affected source would be required to maintain records of
the results of compliance tests for each of the proposed emission
limits, including THC, lead, and HCl/Cl2. These records are
necessary to document the initial compliance determination with these
standards. If a smelter is subject to the proposed emission standards
for THC and must monitor afterburner or exhaust stream temperature to
comply with the proposed enhanced monitoring requirements, then records
of the afterburner or exhaust stream temperature would be maintained.
These records could be in the form of strip charts or digital
printouts, with the period between measurements not to exceed 15
minutes. A block average temperature would be recorded every 3 hours.
These records would be used by an affected source to demonstrate
continuous compliance with the THC standards.
The source would be required to maintain records explaining any
periods when the monitored afterburner temperature dropped below the
minimum established during the facility's initial THC compliance test.
Maintenance records of the afterburner temperature monitor would also
be required pursuant to section 63.10 of the General Provisions. All
secondary lead smelters that currently operate afterburners already
monitor and record afterburner temperature as part of normal
afterburner operation and maintenance. Therefore, the incremental
burden associated with these proposed recordkeeping requirements for
temperature are considered minimal.
Each source would be required to maintain records of opacity, as
measured by a COM and in terms of 6-minute averages. Records would also
be maintained of any exceedances of the site-specific opacity limit and
any corrective actions following those exceedances. Maintenance records
of the opacity monitor probes would also be maintained, including
records of periodic cleaning and replacements and calibration checks,
pursuant to section 63.10 of the General Provisions. These records
would be used to demonstrate continuous compliance with the opacity
standard.
Each source would also be required to maintain records consistent
with the enhanced monitoring approach chosen for controlling HCl/
Cl2 emissions to ensure that the source is in continuous
compliance with the HCl/Cl2 standard. If an owner or operator
chooses to rely on fluxing as a control for HCl/Cl2, records of
the soda ash or limestone added to the smelting furnace and the total
amount of material charged would have to be maintained. The amount of
fluxing agent added and material charged would be recorded on a total-
per-shift basis. Most smelters already maintain records of fluxing
agents added to the furnace and material charged as a normal part of
production and quality control. Consequently, the incremental burden
associated with this recordkeeping requirement would be minimal.
If a source operates an acid gas scrubber and the owner or operator
chooses to control HCl and Cl2 with the scrubber rather than
through fluxing, then the source would be required to either (1)
maintain records of scrubber media injection rate and pH, or (2)
maintain records of SO2 concentrations measured continuously with
a CMS. Most sources with scrubbers already maintain records of media
injection rate and pH as part of normal scrubber operation, as well as
CMS's for SO2. If a source operates a CMS for HCl, it would
maintain records of HCl concentration.
Records would also be maintained of fugitive dust control
activities, as required by each smelter's SOP.
2. Reporting
Owners or operators of secondary lead smelters would be required to
comply with all of the reporting requirements under section 63.10 of
the General Provisions. They would be required to report the results of
performance tests and CMS performance evaluations, and to submit
quarterly excess emissions and CMS performance reports or summary
reports.
These quarterly reports would include summaries (e.g., 3-hour
averages) of the records required to demonstrate continuous compliance
with the proposed standards. These reports would also contain summaries
of the records that are required to demonstrate continuous compliance
with the fugitive dust control measures described in the source's SOP
manual, including an explanation of the periods when the procedures
outlined in the SOP were not followed.
The Administrator believes that excess emissions and compliance
parameter monitoring reports are a critical enforcement tool.
Therefore, the proposed standard would require quarterly, rather than
semi-annual reports. However, pursuant to section 63.10(e)(3)(ii) of
the General Provisions, sources may request to reduce reporting
frequency after they can demonstrate continuous compliance for a one-
year period.
L. Operating Permit Program
Under title V of the Act, all HAP-emitting sources would be
required to obtain an operating permit. Oftentimes, the emission limits
and the requirements for monitoring, reporting, and recordkeeping for a
facility are scattered among numerous provisions of State
Implementation Plans or Federal regulations. As discussed in the final
rule for the operating permit program, published on July 21, 1992 (57
FR 32295), an operating permit under this new permit program will
include all of the requirements that pertain to a single source in a
single document.
After a State's permit program has been approved, each secondary
lead smelter within that State must apply for and obtain an operating
permit. If the State where the secondary lead smelter is located does
not have an approved permitting program, the owner or operator must
submit the application under the General Provisions of 40 CFR part 63.
The addresses for the EPA Regional Offices and States are included in
the General Provisions.
M. Whether to Also Regulate Air Emissions Under RCRA
As noted earlier, air emissions from secondary lead smelting
furnaces are also potentially subject to regulation under RCRA because
the battery and other lead-bearing secondary feed is often classified
as a hazardous waste because of lead content. These emissions are
presently exempt from regulation (40 CFR 266.100(c)), but the EPA is
considering whether RCRA controls are necessary as part of this
rulemaking. The EPA has agreed to reexamine the appropriateness of the
exemption as part of a settlement agreement in Horsehead Resources Inc.
v. Browner, No. 92-1221. The settlement agreement provides that the EPA
may issue revised regulatory standards under the Act alone, under RCRA,
or under both statutes.
The EPA is proposing to continue exempting air emissions from
secondary lead smelting furnaces from RCRA essentially because the EPA
believes these emissions will be comprehensively and adequately
regulated under the section 112 rules proposed here, plus the
subsequent residual risk determination. Although the RCRA standard for
regulation [''as may be necessary to protect human health and the
environment'', RCRA section 3004 (a)] differs from the initial
technology-based regime of section 112 of the Act, the EPA does not
believe that further RCRA regulation of air emissions is necessary. The
reasons are that: (1) The proposed MACT optimizes control of the
principal HAP contributed by the hazardous waste (i.e. lead-bearing
feed, as opposed to fossil fuels) processed by the source by imposing
the best pollution control technology for the principal HAP--lead
compounds--emitted from these sources; (2) all secondary lead smelters
(both major and area sources) would be controlled by the proposed
standards; (3) the proposed standards control not only stack emissions,
but facility-wide fugitive emissions; (4) organic HAP's are controlled
as well, and emissions of chlorinated organic HAP's (such as PCDD's and
PCDF's) are minimal; and (5) HCl and Cl2 emissions are controlled
as well. To the extent any significant residual risk remains after MACT
standards are implemented, the risk will be addressed through the
section 112(f) residual risk process. Consequently, the EPA believes
that RCRA regulation of air emissions from these sources should not be
required.
In this regard, it is important to remember that RCRA section 1006
requires the Agency to ``integrate all provisions of [RCRA] for
purposes of administration and enforcement and * * * avoid duplication,
to the maximum extent practicable, with the appropriate provisions of
the Clean Air Act * * * .''. The EPA believes that imposition of RCRA
air emission standards for these sources could result in the types of
unnecessary duplication that section 1006 is intended to prevent.
Accordingly, the Agency is proposing to retain the current regulatory
exemption from RCRA regulation for air emissions from secondary lead
smelters.
There is also a second potential area of overlap between RCRA
standards and the proposed MACT standards. This is with respect to
strategy units that are presently regulated under RCRA. The EPA
believes that the controls for fugitive dust emissions proposed in this
rule (proposed Secs. 63.545 (c)(2) and (c)(5) in particular) are
consistent with, and complement, the existing RCRA standards. The RCRA
standards are directed largely at preventing releases of waste to land
and groundwater, and so would be complemented by the proposed rules,
which are directed to preventing exposure via an air exposure pathway.
In addition, the provisions of the RCRA rules preventing air emissions
are consistent with the standards proposed today. For example,
Sec. 264.1101(c)(1)(iv) prevents fugitive dust emissions from
containment buildings by prohibiting visible emissions and achieves the
same emission control objective of the fugitive dust control standards
being proposed today. The Agency solicits comment, however, to ensure
that none of the requirements for RCRA storage units are incompatible
with the standards proposed today.
N. Solicitation of Comments
The EPA welcomes comments on all aspects of the proposed standards
and specifically solicits comments on the following: (1) The
determination by the EPA that area sources in the category present a
threat of adverse effects to human health and therefore should be
regulated; (2) the use of fluxing agents to eliminate HCl and Cl2
emissions from smelting furnaces, including the technical feasibility
of this approach, any adverse impacts on smelting operations, and its
effectiveness in reducing HCl/Cl2 emissions; (3) the feasibility
and impacts of establishing a THC limit for existing blast furnaces
based on an afterburner temperature above that identified as the MACT
floor (700 deg.C); and (4) the proposed enhanced monitoring
requirements, including the proposed strategy of establishing a site-
specific opacity limit concurrent with the initial lead compliance
test. Comments on these aspects of the standards will be most useful if
they contain specific information and data pertinent to an evaluation
of the magnitude and severity of the impact(s) and suggested
alternative courses of action that would avoid the impact(s).
VII. Administrative Requirements
A. Public Hearing
A public hearing will be held, if requested, to discuss the
proposed standards for secondary lead smelters, in accordance with
section 307(d)(5) of the Act. Persons wishing to make an oral
presentation at a public hearing should contact the EPA at the address
given in the ADDRESSES section of this preamble. Oral presentations
will be limited to 15 minutes each. Any member of the public may file a
written statement before, during, or within 30 days after the hearing.
Written statements should be addressed to the Air Docket Section
address given in the ADDRESSES section of this preamble and should
refer to Docket No. A-92-43. A verbatim transcript of the hearing and
written statements will be available for public inspection and copying
during normal working hours at the EPA's Air Docket Section in
Washington, DC (see ADDRESSES section of this preamble).
B. Docket
The docket is an organized and complete file of all the information
submitted to, or otherwise considered by, the EPA in the development of
this proposed rule. The principal purposes of the docket are to: (1)
Allow interested parties to readily identify and locate documents so
they can intelligently and effectively participate in the rulemaking
process, and (2) serve as the record in case of judicial review, except
for interagency review materials [section 307(d)(7)(a) of the CAA].
C. Executive Order 12866
Under Executive Order 12866 (58 FR 5173, October 4, 1993), the EPA
must determine whether a regulatory action is ``significant'' and,
therefore, subject to Office of Management and Budget (OMB) review and
the requirements of the Executive Order. The Order defines
``significant'' regulatory action as one that is likely to lead to a
rule that may: (1) Have an annual effect on the economy of $100 million
or more, or adversely and materially affect a sector of the economy,
productivity, competition, jobs, the environment, public health or
safety, or State, local, or tribal governments or communities; (2)
create a serious inconsistency or otherwise interfere with an action
taken or planned by another agency; (3) materially alter the budgetary
impact of entitlements, grants, user fees, or loan programs or the
rights and obligation of recipients thereof; or (4) raise novel legal
or policy issues arising out of legal mandates, the President's
priorities, or the principles set forth in the Executive Order.
The proposed regulation presented in this notice was submitted to
the OMB for review. Any written EPA response to those comments are
included in the docket listed at the beginning of today's notice under
ADDRESSES. The docket is available for public inspection at EPA's Air
Docket Section, which is listed in the ADDRESSES section of this
preamble.
D. Paperwork Reduction Act
The information collection requirements in this proposed rule were
submitted for approval to OMB under the Paperwork Reduction Act, 44
U.S.C. 3501 et seq. An Information Collection Request document was
prepared by the EPA (ICR No. 1686.01), and a copy may be obtained from
Sandy Farmer, Information Policy Branch, U.S. Environmental Protection
Agency, 401 M Street SW. (2136), Washington, DC 20460, or by calling
(202) 260-2740. The public reporting burden for this collection of
information (including emission testing) is estimated to average 1,200
hours per smelter for reporting in the first year in which compliance
is demonstrated and 550 hours per year for subsequent years, and to
require 210 hours annually per smelter for recordkeeping. These
estimates include time for reviewing instructions, searching existing
data sources, gathering and maintaining the data needed, and completing
and reviewing the collection of information.
Send comments regarding the burden estimate or any other aspect of
this collection of information, including suggestions for reducing this
burden, to Chief, Information Policy Branch, 2136, U.S. Environmental
Protection Agency, 401 M Street, SW., Washington, DC 20460, and to the
Office of Information and Regulatory Affairs, Office of Management and
Budget, Washington, DC 20503, marked ``Attention: Desk Officer for
EPA.'' The final rule will respond to any OMB or public comments on the
information collection requirements contained in this proposal.
E. Regulatory Flexibility Act
The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires the
EPA to consider potential impacts of proposed regulations on small
business entities. If a preliminary analysis indicates that a proposed
regulation would have any economic impact on any small entities, then a
regulatory flexibility analysis must be prepared.
Present Regulatory Flexibility Act guidelines indicate that an
economic impact should be considered significant if it meets one of the
following criteria: (1) Compliance increases annual production costs by
more than 5 percent, assuming costs are passed on to consumers; (2)
compliance costs as a percentage of sales for small entities are at
least 10 percent more than compliance costs as a percentage of sales
for large entities; (3) capital costs of compliance represent a
significant portion of capital available to small entities, considering
internal cash flow plus external financial capabilities; or (4)
regulatory requirements are likely to result in closure of small
entities. Based on discussions with technical support experts, the EPA
formulated alternative criteria for the determination of significant
impacts in the secondary lead industry. The guidelines were discussed
in the economic impacts section of this preamble.
The results of an economic assessment indicated that the proposed
rule will have an economic impact on small business entities. However,
adverse economic impacts have been minimized to the greatest extent
possible in this rule making, and those that remain are unavoidable.
All of the small entities that are currently operating and that are
impacted are major sources of HAP's for which the EPA is required to
propose MACT standards. Consequently, the economic impacts can not be
minimized by proposing less stringent standards based on GACT. The
standards being proposed in this rule making are based on MACT floor
controls, and in no instance did the EPA choose to propose standards
based on controls more stringent than the floor. The EPA was also able
to identify alternatives to add-on controls (e.g., process
modifications and work practices) in the MACT floors that offered
equivalent levels of control.
The EPA has minimized the impacts associated with monitoring by
adopting a surrogate pollutant approach and by allowing for alternative
monitoring strategies when available. Finally, the EPA has minimized
the impacts associated with recordkeeping and reporting by proposing
only the minimum requirements needed to document continuous compliance
with the proposed emission limits.
F. Pollution Prevention Considerations
Pollution prevention/source reduction is the use of process
modifications or alternative processing technologies to reduce air
pollutant emissions from the source, rather than through the use of
add-on controls. Several pollution prevention and source reduction
options were considered for application to the secondary lead smelter
industry in this rulemaking. These options are described in more detail
in chapter 3 of the BID.
1. Emission Prevention Through Electrowinning
Electrowinning is a process to recover lead metal by dissolving
lead compounds in acid and then depositing lead metal on a cathode in
an electrolytic cell. Electrowinning is being developed as an
alternative to the use of smelting furnaces to reduce lead compounds to
lead metal. Electrowinning would reduce potential emissions of metal
HAP's, organic HAP's, and HCl/Cl2. This process is still
experimental and has not been demonstrated on a commercial basis
anywhere in the world. However, the proposed standards would not
prevent a smelter from pursuing this technology. The proposed standards
for process sources are in the form of emission limits and operators
may use any technology that can achieve the emission limit. There are
no design, equipment, or work practice requirements that would
discourage or prohibit the use of this technology.
2. Organic HAP and HCl/Chlorine Emission Prevention Through Plastic
Removal
Plastic battery separators are sources of organic HAP and HCl/
Cl2 emissions from smelting furnaces. Technology is available to
remove these materials from the furnace feed material and this may
decrease organic HAP and HCl/Cl2 emissions. However, no data are
available to confirm such a decrease and the recycling options for the
recovered material are limited. Material that is not recycled would
need to be disposed of as hazardous waste if it is contaminated with
lead. However, the proposed standards would not prevent a smelter from
pursuing this option.
3. HCl and Chlorine Emission Prevention Through Fluxing
Soda ash or limestone can be added to a smelting furnace to prevent
emissions of HCl and Cl2. The use of fluxing agents would avoid
the need for a wet scrubber and the solid waste and wastewater impacts
associated with a wet scrubber. This practice is currently in use in
the secondary lead industry and is incorporated in the proposed
regulation.
4. HCl and Chlorine Emission Prevention Through Dechlorination of Flue
Dust
Chlorine is found in the flue dust of secondary lead smelters in
the form of lead chloride. Recycling the flue dust to the smelting
furnace causes the chlorine to build up in the furnace and baghouse
system until it is released as HCl or Cl2, unless it is removed in
the slag. The same technology that can be used to perform paste
desulfurization can be used to remove chlorine from the flue dust by
diverting the flue dust to the paste desulfurization system before
recycling it to the furnace. This strategy is being used by at least
one secondary lead smelter and it appears to be as effective as fluxing
in the control of HCl and Cl2 emissions. The proposed standards
would not prevent smelters from pursuing this option.
G. Miscellaneous
In accordance with section 117 of the Act, publication of this
proposal was preceded by consultation with appropriate advisory
committees, independent experts, and Federal departments and agencies.
The Administrator welcomes comments on all aspects of the proposed
regulation, including health, economic, and technological issues, and
on the proposed test methods.
This regulation will be reviewed 8 years from the date of
promulgation. This review will include an assessment of such factors as
evaluation of residual health risks, any overlap with other programs,
the existence of alternative methods, enforceability, improvements in
emission control technology and health data, and the recordkeeping and
reporting requirements.
VIII. Statutory Authority
The statutory authority for this proposal is provided by sections
101, 112, 114, 116, and 301 of the Clean Air Act, as amended; 42
U.S.C., 7401, 7412, 7414, 7416, and 7601.
List of Subjects in 40 CFR Part 63
Environmental protection, Air pollution control, Hazardous
substances, Reporting and recordkeeping requirements, Secondary lead
smelters.
Dated: May 27, 1994.
Carol M. Browner,
Administrator.
[FR Doc. 94-13667 Filed 6-8-94; 8:45 am]
BILLING CODE 6560-50-P