National Emission Standards for Hazardous Air Pollutants (NESHAP) (Secondary Lead Smelters)

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, howeve

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