National Emission Standards for Hazardous Air Pollutants: Area Source Standards for Nine Metal Fabrication and Finishing Source Categories

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 63

[EPA-HQ-OAR-2006-0306; FRL-8547-2]

RIN 2060-AO27

National Emission Standards for Hazardous Air Pollutants: Area Source Standards for Nine Metal Fabrication and Finishing Source Categories

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Proposed rule.

SUMMARY:

EPA is proposing national emission standards for control of hazardous air pollutants (HAP) for nine metal fabrication and finishing area source categories. This rule proposes emission standards in the form of management practices and equipment standards for new and existing operations of dry abrasive blasting, machining, dry grinding and dry polishing with machines, spray painting and other spray coating, and welding operations. These proposed standards reflect EPA's determination regarding the generally achievable control technology (GACT) and/or management practices for the nine area source categories.

DATES:

Comments must be received on or before May 5, 2008, unless a public hearing is requested by April 14, 2008. If a hearing is requested on this proposed rule, written comments must be received by May 19, 2008. Under the Paperwork Reduction Act, comments on the information collection provisions must be received by OMB on or before May 5, 2008.

ADDRESSES:

Submit your comments, identified by Docket ID No. EPA-HQ-OAR-2006-0306, by one of the following methods:

•

http://www.regulations.gov

: Follow the on-line instructions for submitting comments.

•

E-mail: a-and-r-Docket@epa.gov

.

•

Fax:

(202) 566-9744.

•

Mail:

National Emission Standards for Hazardous Air

Pollutants

: Area Source Standards for Metal Fabrication and Finishing Operations Docket, Environmental Protection Agency, Air and Radiation Docket and Information Center, Mailcode: 2822T, 1200 Pennsylvania Ave., NW., Washington, DC 20460. Please include a total of two copies. In addition, please mail a copy of your comments on the information collection provisions to the Office of Information and Regulatory Affairs, Office of Management and Budget (OMB), Attn: Desk Officer for EPA, 725 17th St., NW., Washington, DC 20503.

•

Hand Delivery:

EPA Docket Center, Public Reading Room, EPA West, Room 3334, 1301 Constitution Ave., NW., Washington, DC 20460. Such deliveries are only accepted during the Docket's normal hours of operation, and special arrangements should be made for deliveries of boxed information.

Instructions:

Direct your comments to Docket ID No. EPA-HQ-OAR-2006-0306. EPA's policy is that all comments received will be included in the public docket without change and may be made available online at

http://www.regulations.gov

, including any personal information provided, unless the comment includes information claimed to be confidential business information (CBI) or other information whose disclosure is restricted by statute. Do not submit information that you consider to be CBI or otherwise protected through

http://www.regulations.gov

or e-mail. The

http://www.regulations.gov

Web site is an “anonymous access” system, which means EPA will not know your identity or contact information unless you provide it in the body of your comment. If you send an e-mail comment directly to EPA without going through

http://www.regulations.gov

, your e-mail address will be automatically captured and included as part of the comment that is placed in the public docket and made available on the Internet. If you submit an electronic comment, EPA recommends that you include your name and other contact information in the body of your comment and with any disk or CD-ROM you submit. If EPA cannot read your comment due to technical difficulties and cannot contact you for clarification, EPA may not be able to consider your comment. Electronic files should avoid the use of special characters, any form of encryption, and be free of any defects or viruses.

Docket:

All documents in the docket are listed in the

http://www.regulations.gov

index. Although listed in the index, some information is not publicly available, e.g., CBI or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in hard copy form. Publicly available docket materials are available either electronically through

http://www.regulations.gov

or in hard copy at the NESHAP for Metal Fabrication and Finishing Area Sources Docket, at the EPA Docket and Information Center, EPA West, Room 3334, 1301 Constitution Ave., NW., Washington, DC. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the Air Docket is (202) 566-1742.

FOR FURTHER INFORMATION CONTACT:

Dr. Donna Lee Jones, Sector Policies and Programs Division, Office of Air Quality Planning and Standards (D243-02), Environmental Protection Agency, Research Triangle Park, North Carolina 27711,

telephone number:

(919) 541-5251;

fax number

: (919) 541-3207;

e-mail address

:

jones.donnalee@epa.gov

.

SUPPLEMENTARY INFORMATION:

Outline

. The information in this preamble is organized as follows:

I. General Information

A. Does this action apply to me?

B. What should I consider as I prepare my comments to EPA?

C. Where can I get a copy of this document?

D. When would a public hearing occur?

II. Background Information for Proposed Area Source Standards

A. What is the statutory authority and regulatory approach for the proposed standards?

B. What source categories are affected by the proposed standards?

C. What are the production operations, emission sources, and available controls?

III. Summary of Proposed Standards

A. Do the proposed standards apply to my source?

B. When must I comply with the proposed standards?

C. For what processes is EPA proposing standards?

D. What emissions control requirements is EPA proposing?

E. What are the initial compliance provisions?

F. What are the continuous compliance requirements?

G. What are the notification, recordkeeping, and reporting requirements?

IV. Rationale for This Proposed Rule

A. How did we select the source category?

B. How did we select the affected sources?

C. How did we determine the regulated processes?

D. How was GACT determined?

E. How did we select the compliance requirements?

F. How did we decide to exempt this area source category from title V permit requirements?

V. Impacts of the Proposed Standards

A. What are the air impacts?

B. What are the cost impacts?

C. What are the economic impacts?

D. What are the non-air health, environmental, and energy impacts?

VI. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

B. Paperwork Reduction Act

C. Regulatory Flexibility Act

D. Unfunded Mandates Reform Act

E. Executive Order 13132: Federalism

F. Executive Order 13175: Consultation and Coordination With Indian Tribal Governments

G. Executive Order 13045: Protection of Children From Environmental Health and Safety Risks

H. Executive Order 13211: Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use

I. National Technology Transfer Advancement Act

J. Executive Order 12898: Federal Actions To Address Environmental Justice in Minority Populations and Low-Income Populations

I. General Information

A. Does this action apply to me?

The regulated categories and entities potentially affected by this proposed action are shown in the table below. This proposed rule applies only to facilities that are an area source of the compounds of cadmium, chromium, lead, manganese, and nickel, or an area source of volatile organic HAP (VOHAP) from spray painting operations, and which perform metal fabrication or finishing operations in one of the following nine source categories: (1) Electrical and Electronic Equipment Finishing Operations; (2) Fabricated Metal Products; (3) Fabricated Plate Work (Boiler Shops); (4) Fabricated Structural Metal Manufacturing; (5) Heating Equipment, except Electric; (6) Industrial Machinery and Equipment: Finishing Operations; (7) Iron and Steel Forging; (8) Primary Metal Products Manufacturing; and (9) Valves and Pipe Fittings. Facilities affected by this proposed rule are not subject to the miscellaneous coating requirements in 40 CFR part 63, subpart HHHHHH, “National Emission Standards for Hazardous Air Pollutants: Paint Stripping and Miscellaneous Surface Coating Operations at Area Sources,” for their affected source(s) that are subject to the requirements of this proposed rule. There potentially may be other sources at the facility not subject to the requirements of this proposed rule that are instead subject to subpart HHHHHH of this part.

Metal fabrication and finishing

category

NAICS Codes

1

Examples of Regulated Entities

Electrical and Electronics Equipment Finishing Operations

335999

Establishments primarily engaged in manufacturing motors and generators and electrical machinery, equipment, and supplies, not elsewhere classified. The electrical machinery equipment and supplies industry sector includes facilities primarily engaged in high energy particle acceleration systems and equipment, electronic simulators, appliance and extension cords, bells and chimes, insect traps, and other electrical equipment and supplies, not elsewhere classified. The Motors and Generators Manufacturing industry sector includes those establishments primarily engaged in manufacturing electric motors (except engine starting motors) and power generators; motor generator sets; railway motors and control equipment; and motors, generators and control equipment for gasoline, electric, and oil-electric buses and trucks.

Fabricated Metal Products

332117

Establishments primarily engaged in manufacturing fabricated metal products, such as fire or burglary resistive steel safes and vaults and similar fire or burglary resistive products; and collapsible tubes of thin flexible metal. Also included are establishments primarily engaged in manufacturing powder metallurgy products, metal boxes; metal ladders; metal household articles, such as ice cream freezers and ironing boards; and other fabricated metal products not elsewhere classified.

Fabricated Plate Work (Boiler Shops)

332313, 332410, 332420

Establishments primarily engaged in manufacturing power and marine boilers, pressure and nonpressure tanks, processing and storage vessels, heat exchangers, weldments and similar products.

Fabricated Structural Metal Manufacturing

332312

Establishments primarily engaged in fabricating iron and steel or other metal for structural purposes, such as bridges, buildings, and sections for ships, boats, and barges.

Heating Equipment, except Electric

333414

Establishments primarily engaged in manufacturing heating equipment, except electric and warm air furnaces, including gas, oil, and stoker coal fired equipment for the automatic utilization of gaseous, liquid, and solid fuels. Typical products produced in this source category include low-pressure heating (steam or hot water) boilers, fireplace inserts, domestic (steam or hot water) furnaces, domestic gas burners, gas room heaters, gas infrared heating units, combination gas-oil burners, oil or gas swimming pool heaters, heating apparatus (except electric or warm air), kerosene space heaters, gas fireplace logs, domestic and industrial oil burners, radiators (except electric), galvanized iron nonferrous metal range boilers, room heaters (except electric), coke and gas burning salamanders, liquid or gas solar energy collectors, solar heaters, space heaters (except electric), mechanical (domestic and industrial) stokers, wood and coal-burning stoves, domestic unit heaters (except electric), and wall heaters (except electric).

Industrial Machinery and Equipment: Finishing Operations

333120, 333132, 333911

Establishments primarily engaged in construction machinery manufacturing, oil and gas field machinery manufacturing, and pumps and pumping equipment manufacturing. Finishing operations include the collection of all operations associated with the surface coating of industrial machinery and equipment. The construction machinery manufacturing industry sector includes establishments primarily engaged in manufacturing heavy machinery and equipment of types used primarily by the construction industries, such as bulldozers; concrete mixers; cranes, except industrial plan overhead and truck-type cranes; dredging machinery; pavers; and power shovels. Also included in this industry are establishments primarily engaged in manufacturing forestry equipment and certain specialized equipment, not elsewhere classified, similar to that used by the construction industries, such as elevating platforms, ship cranes and capstans, aerial work platforms, and automobile wrecker hoists. The oil and gas field machinery manufacturing industry sector includes establishments primarily engaged in manufacturing machinery and equipment for use in oil and gas field or for drilling water wells, including portable drilling rigs. The pumps and pumping equipment industry sector includes establishments primarily engaged in manufacturing pumps and pumping equipment for general industrial, commercial, or household use, except fluid power pumps and motors. This category includes establishments primarily engaged in manufacturing domestic water and sump pumps.

Iron and Steel Forging

33211

Establishments primarily engaged in the forging manufacturing process, where purchased iron and steel metal is pressed, pounded or squeezed under great pressure into high strength parts known as forgings. The process is usually performed hot by preheating the metal to a desired temperature before it is worked. The forging process is different from the casting and foundry processes, as metal used to make forged parts is never melted and poured.

Primary Metals Products Manufacturing

332618

Establishments primarily engaged in manufacturing products such as fabricated wire products (except springs) made from purchased wire. These facilities also manufacture steel balls; nonferrous metal brads and nails; nonferrous metal spikes, staples, and tacks; and other primary metals products not elsewhere classified.

Valves and Pipe Fittings

332919

Establishments primarily engaged in manufacturing metal valves and pipe fittings; flanges; unions, with the exception of purchased pipes; and other valves and pipe fittings not elsewhere classified.

1

North American Industry Classification System.

This table is not intended to be exhaustive, but rather provide a guide for readers regarding entities likely to be affected by this action. To determine whether your facility would be regulated by this action you can refer to the descriptions in section (II)(B) below. For descriptions of the North American Industry Classification System (NAICS) codes, you can view information on the U.S. Census site at

http://www.census.gov/epcd/ec97brdg

. If you have any questions regarding the applicability of this action to a particular entity, consult either the air permit authority for the entity or your EPA regional representative as listed in 40 CFR 63.13 of subpart A (General Provisions).

B. What should I consider as I prepare my comments to EPA?

Do not submit information containing CBI to EPA through

http://www.regulations.gov

or e-mail. Send or deliver information identified as CBI only to the following address: Roberto Morales, OAQPS Document Control Officer (C404-02), Environmental Protection Agency, Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina 27711, Attention Docket ID EPA-HQ-OAR-2006-0306. Clearly mark the part or all of the information that you claim to be CBI. For CBI information in a disk or CD-ROM that you mail to EPA, mark the outside of the disk or CD-ROM as CBI and then identify electronically within the disk or CD-ROM the specific information that is claimed as CBI. In addition to one complete version of the comment that includes information claimed as CBI, a copy of the comment that does not contain the information claimed as CBI must be submitted for inclusion in the public docket. Information so marked will not be disclosed except in accordance with procedures set forth in 40 CFR part 2.

C. Where can I get a copy of this document?

In addition to being available in the docket, an electronic copy of this proposed action will also be available on the Worldwide Web (WWW) through EPA's Technology Transfer Network (TTN). A copy of this proposed action will be posted on the TTN's policy and guidance page for newly proposed or promulgated rules at the following address:

http://www.epa.gov/ttn/oarpg/

. The TTN provides information and technology exchange in various areas of air pollution control.

D. When would a public hearing occur?

If anyone contacts EPA requesting to speak at a public hearing concerning this proposed rule by April 14, 2008, we will hold a public hearing on April 18, 2008. If you are interested in attending the public hearing, contact Ms. Pamela Garrett at (919) 541-7966 to verify that a hearing will be held. If a public hearing is held, it will be held at 10 a.m.

at the EPA's Environmental Research Center Auditorium, Research Triangle Park, NC, or an alternate site nearby.

II. Background Information for Proposed Area Source Standards

A. What is the statutory authority and regulatory approach for the proposed standards?

Section 112(d) of the CAA requires us to establish national emission standards for hazardous air pollutants (NESHAP) for both major and area sources of HAP that are listed for regulation under CAA section 112(c). A major source emits or has the potential to emit 10 tons per year (tpy) or more of any single HAP or 25 tpy or more of any combination of HAP. An area source is a stationary source that is not a major source.

Section 112(k)(3)(B) of the CAA calls for EPA to identify at least 30 HAP which, as the result of emissions from area sources, pose the greatest threat to public health in the largest number of urban areas. EPA implemented this provision in 1999 in the Integrated Urban Air Toxics Strategy (64 FR 38715, July 19, 1999). Specifically, in the Strategy, EPA identified 30 HAP that pose the greatest potential health threat in urban areas, and these HAP are referred to as the “30 urban HAP.” Section 112(c)(3) requires EPA to list sufficient categories or subcategories of area sources to ensure that area sources representing 90 percent of the emissions of the 30 urban HAP are subject to regulation. We implemented these requirements through the Integrated Urban Air Toxics Strategy (64 FR 38715, July 19, 1999). A primary goal of the Strategy is to achieve a 75 percent reduction in cancer incidence attributable to HAP emitted from stationary sources.

Under CAA section 112(d)(5), we may elect to promulgate standards or requirements for area sources “which provide for the use of GACT or management practices by such sources to reduce emissions of hazardous air pollutants.” Additional information on GACT is found in the Senate report on the legislation (Senate Report Number 101-228, December 20, 1989), which describes GACT as:

* * * methods, practices and techniques which are commercially available and appropriate for application by the sources in the category considering economic impacts and the technical capabilities of the firms to operate and maintain the emissions control systems.

Consistent with the legislative history, we can consider costs and economic impacts in determining GACT, which is particularly important when developing regulations for source categories that may have many small businesses.

Determining what constitutes GACT involves considering the control technologies and management practices that are generally available to the area sources in the source category. We also consider the standards applicable to major sources in the same industrial sector to determine if the control technologies and management practices are transferable and generally available to area sources. In appropriate circumstances, we may also consider technologies and practices at area and major sources in similar categories to determine whether such technologies and practices could be considered generally available for the area source category at issue. Finally, as noted above, in determining GACT for a particular area source category, we consider the costs and economic impacts of available control technologies and management practices on that category.

We are proposing these national emission standards in response to a court-ordered deadline that requires EPA to issue standards for 11 source categories listed pursuant to section 112(c)(3) and (k) by June 15, 2008 (

Sierra Club

v.

Johnson

, no. 01-1537, D.D.C., March 2006). We have already issued regulations addressing one of the 11 area source categories. See regulations for Wood Preserving (

Federal Register

, 72 (135), July 16, 2007.) Other rulemakings will include standards for the remaining source categories that are due in June 2008.

B. What source categories are affected by these proposed standards?

These proposed standards would affect any facility that performs metal fabrication or finishing operations in one of the following nine metal fabrication and finishing area source categories: (1) Electrical and Electronic Equipment Finishing Operations; (2) Fabricated Metal Products; (3) Fabricated Plate Work (Boiler Shops); (4) Fabricated Structural Metal Manufacturing; (5) Heating Equipment, except Electric; (6) Industrial Machinery and Equipment: Finishing Operations; (7) Iron and Steel Forging; (8) Primary Metal Products Manufacturing; and (9) Valves and Pipe Fittings. Throughout this proposed rule, we refer to the nine metal fabrication and finishing source categories collectively as “metal fabrication or finishing operations.”

The following are descriptions of the nine metal fabrication and finishing source categories:

Electrical and Electronic Equipment Finishing Operations:

This category includes establishments primarily engaged in manufacturing motors and generators and electrical machinery, equipment, and supplies, not elsewhere classified, and includes facilities primarily engaged in high energy particle acceleration systems and equipment, electronic simulators, appliance and extension cords, bells and chimes, insect traps, and other electrical equipment and supplies not elsewhere classified. This category also includes those establishments primarily engaged in manufacturing electric motors (except engine starting motors) and power generators; motor generator sets; railway motors and control equipment; and motors, generators and control equipment for gasoline, electric, and oil-electric buses and trucks.

Fabricated Metal Products, Not Elsewhere Classified:

This category includes establishments primarily engaged in manufacturing fabricated metal products, such as fire or burglary resistive steel safes and vaults and similar fire or burglary resistive products; and collapsible tubes of thin flexible metal. Also included are establishments primarily engaged in manufacturing powder metallurgy products, metal boxes; metal ladders; metal household articles, such as ice cream freezers and ironing boards; and other fabricated metal products not elsewhere classified.

Fabricated Plate Work (Boiler Shops):

This category includes establishments primarily engaged in manufacturing power and marine boilers, pressure and nonpressure tanks, processing and storage vessels, heat exchangers, weldments and similar products.

Fabricated Structural Metal Manufacturing:

This category includes establishments primarily engaged in fabricating iron and steel or other metal for structural purposes, such as bridges, buildings, and sections for ships, boats, and barges.

Heating Equipment, except Electric:

This category includes establishments primarily engaged in manufacturing heating equipment, except electric and warm air furnaces, including gas, oil, and stoker coal fired equipment for the automatic utilization of gaseous, liquid, and solid fuels. Typical products produced in this source category include low-pressure heating (steam or hot water) boilers, fireplace inserts, domestic (steam or hot water) furnaces, domestic gas burners, gas room heaters, gas infrared heating units, combination gas-oil burners, oil or gas swimming pool heaters, heating apparatus (except electric or warm air), kerosene space heaters, gas fireplace logs, domestic and industrial oil burners, radiators (except

electric), galvanized iron nonferrous metal range boilers, room heaters (except electric), coke and gas burning salamanders, liquid or gas solar energy collectors, solar heaters, space heaters (except electric), mechanical (domestic and industrial) stokers, wood and coal-burning stoves, domestic unit heaters (except electric), and wall heaters (except electric).

Industrial Machinery and Equipment Finishing Operations:

This category includes establishments primarily engaged in construction machinery manufacturing, oil and gas field machinery manufacturing, and pumps and pumping equipment manufacturing. Finishing operations include the collection of all operations associated with the surface coating of industrial machinery and equipment. This category includes establishments primarily engaged in manufacturing heavy machinery and equipment of types used primarily by the construction industries, such as bulldozers; concrete mixers; cranes, except industrial plant overhead and truck-type cranes; dredging machinery; pavers; and power shovels. Also included in this industry are establishments primarily engaged in manufacturing forestry equipment and certain specialized equipment, not elsewhere classified, similar to that used by the construction industries, such as elevating platforms, ship cranes and capstans, aerial work platforms, and automobile wrecker hoists. This category also includes establishments primarily engaged in manufacturing machinery and equipment for use in oil and gas fields or for drilling water wells, including portable drilling rigs. This category includes establishments primarily engaged in manufacturing pumps and pumping equipment for general industrial, commercial, or household use, except fluid power pumps and motors, and establishments primarily engaged in manufacturing domestic water and sump pumps.

Iron and Steel Forging:

This category includes establishments primarily engaged in the forging manufacturing process, where purchased iron and steel metal is pressed, pounded or squeezed under great pressure into high strength parts known as forgings. The process is usually performed hot by preheating the metal to a desired temperature before it is worked. The forging process is different from the casting and foundry processes, as metal used to make forged parts is never melted and poured.

Primary Metal Products Manufacturing:

This source category includes establishments primarily engaged in manufacturing products such as fabricated wire products (except springs) made from purchased wire. These facilities also manufacture steel balls; nonferrous metal brads and nails; nonferrous metal spikes, staples, and tacks; and other primary metals products not elsewhere classified.

Valves and Pipe Fittings:

This source category includes establishments primarily engaged in manufacturing metal valves and pipe fittings, flanges, and unions, with the exception of from purchased pipes; and other valves and pipe fitting products not elsewhere classified.

We added the nine metal fabrication and finishing source categories to the Integrated Urban Air Toxics Strategy Area Source Category List on November 22, 2002 (67 FR 70427). The inclusion of these source categories to the section 112(c)(3) area source category list is based on 1990 emissions data, as EPA used 1990 as the baseline year for that listing. The nine metal fabrication and finishing source categories were listed for regulation based on emissions of compounds of cadmium, chromium, lead, manganese, and nickel in the 1990 inventory, hereafter referred to as “metal fabrication and finishing metal HAP” (MFHAP). Four of the metal fabrication and finishing source categories were also listed for emissions of the organic HAP trichloroethylene (TCE).

1

Chlorinated solvents such as TCE are used as degreasers in these metal fabrication and finishing source categories. We subsequently discovered that the 1990 emissions data for TCE was for metal fabrication and finishing facilities that used TCE in degreasing operations, which are not part of this source category. Rather, these emission units at both major and area sources are subject to standards for halogenated solvent cleaning under 40 CFR part 63, subpart T. Consequently, we are not proposing standards for TCE from metal fabrication and finishing facilities. The four metal fabrication and finishing source categories listed for TCE emissions remain listed source categories pursuant to section 112(c)(3) of this part. Therefore, we are clarifying that we do not need these four source categories to meet the section 112(c)(3) 90 percent requirement regarding area source emissions of TCE.

1

These four source categories were Electrical and Electronic Equipment Finishing Operations; Fabricated Metal Products; Primary Metal Products Manufacturing; and Valves and Pipe Fittings.

Based on 2002 U.S. Census data and a survey of the industry that we conducted in 2006, we estimate that 5,800 metal fabrication and finishing area source facilities are currently operating in the U.S. Our analyses of 2002 U.S. Census data also indicate that more than 90 percent of the metal fabrication and finishing area source categories is comprised of small businesses, based on the Small Business Administration definition.

A majority of the metal fabrication and finishing area source facilities are estimated to be in urban areas, based on an estimate of 73 percent developed from EPA's 2002 National Emission Inventory (NEI).

2

2

These urban areas are defined to be the urban 1 and urban 2 areas that formed the basis of the listing decisions under 112(c)(3) and (k).

Facilities affected by this proposed rule are not subject to the miscellaneous coating requirements in 40 CFR part 63, subpart HHHHHH, “National Emission Standards for Hazardous Air Pollutants: Paint Stripping and Miscellaneous Surface Coating Operations at Area Sources,” for their affected source(s) that are subject to the requirements of this proposed rule. There potentially may be other sources at the facility not subject to the requirements of this proposed rule that are instead subject to subpart HHHHHH of this part.

C. What are the production operations, emission sources, and available controls?

While these nine source categories produce a wide variety of products, they perform very similar fabrication and finishing operations to create them. There are five general production operations common to metal fabrication and finishing source categories that can emit MFHAP. These five production operations are: (1) Dry abrasive blasting; (2) dry grinding and dry polishing with machines; (3) machining; (4) spray painting and coating; and (5) welding.

As typical within any industry, there is variation in operations between facilities. Also, all facilities do not necessarily employ all five production areas. Information acquired from an EPA survey of 166 facilities showed that for the area sources in the source categories of interest, 39 percent perform dry abrasive blasting, 59 percent perform metal fabrication and finishing with machines, 60 percent perform painting or coating of some kind (that includes but is not limited to spray painting or spray coating), and 65 percent perform welding. More detailed analyses are available in the docket, including estimated percentages of the number of facilities in each category performing each operation.

Another metal fabrication and finishing operation that can emit MFHAP is plating. This operation was noted to be performed by some of the

facilities in the nine metal fabrication and finishing source categories, but is not regulated by this proposed rule. Plating operations are not regulated by this proposed rule because they are regulated elsewhere, as follows: Chromium electroplating tanks are subject to the Chromium Electroplating NESHAP (40 CFR 63, subpart N), while other plating operations at area sources are subject to the Plating and Polishing Area Source Rule (40 CFR part 63, subpart WWWWWW) which will be promulgated by June 15, 2008.

1. Metal Fabrication and Finishing Operations

The nine Metal Fabrication and Finishing source categories produce a wide variety of products using five general production operations that can emit MFHAP: (1) Dry abrasive blasting; (2) dry grinding and dry polishing with machines; (3) machining; (4) spray painting and coating; and (5) welding. The following is a brief description of each of these five fabrication and finishing operations regulated by this proposed rule.

Dry Abrasive Blasting Operations.

This metal fabrication and finishing operation (also referred to in the industry as sand blasting, shot blasting, and shot peening) is used to clean or prepare a surface by forcibly propelling abrasive material against it. Commonly used abrasives include silica sand, glass beads, aluminum oxide, slag, garnet, steel shot, walnut shells, as well as other materials. Common applications of dry abrasive blasting include surface preparation for painting or coating; burr removal after machining, grinding, or welding; matte surface finishing; removal of flash from molded objects.

Two primary aspects differentiate the various types of abrasive blasting: The method of abrasive propulsion and the type of abrasive used. There are three primary methods of propelling the abrasive: Air pressure, using compressed air to propel the abrasive; water pressure, using air or water pressure to propel a wet abrasive slurry; or centrifugal wheels, which use a rotating impeller to mechanically propel the abrasive.

Abrasive blasting covers numerous applications under widely varying conditions. Blasting is also performed outdoors with a portable apparatus or indoors within specially constructed cabinets or enclosures/chambers, either manually, or as part of an automated process line. Because the applications of abrasive blasting are widely varied, there is a similarly wide variety of abrasive blasting equipment available.

Dry abrasive blasting equipment consists of the following general types of systems, listed from small to large: Portable blasters, blast cabinets or “glove boxes”, blast chambers which can be 3 or 4-sided structures, and “bulk” blasters that are totally enclosed and vented to a filtration device to collect and recycle the blast material. Shot peening is a common type of dry abrasive blasting that is a surface treatment used to increase the fatigue life of metal parts. In shot peening, a higher pressure is used to focus the abrasive on a localized area as opposed to general abrasive blasting that may be directed over a larger surface area. Shot peening generally refers to abrasive blasting with metallic or steel pellets, like BB shot. Shot peening is almost always performed in a contained area so that the pellets can be recovered and reused. Similarly, blasting performed with sand other media is also often performed in a contained area so that the media can be recovered and reused.

Dry Grinding and Dry Polishing Operations.

These metal fabrication and finishing operations are very similar and vary only as to their timing in the fabrication and extent of abrasion. Not all parts are polished but most are ground. Grinding is performed on a work piece prior to fabrication or finishing operations to remove undesirable material from the surface or to remove burrs or sharp edges. Grinding is done using belts, disks, or wheels consisting of or covered with various abrasives, e.g., silica, alumina, silicon carbide, garnet, alundum, or emery. Grinding may be performed dry or may use lubricants or coolants such as water or water-based mixtures, solutions, or emulsions containing cutting oils, soaps, detergents, wetting agents, or proprietary compounds. Polishing generally follows grinding. The purpose of the polishing operation is to remove any remaining metal and to prepare the surface for more refined finishing procedures. Burrs on castings or stampings may also be removed by polishing. Polishing is performed using hard-faced wheels constructed of muslin, canvas, felt or leather. Abrasives are applied to the wheels with synthetic adhesives or cements, typically silicate-base cements. The types of abrasives that are used in polishing include both natural and artificial abrasives. Lubricants including oil, grease, tallow, and special bar lubricants are used to prevent gouging and tearing when a fine polished surface is required and also to minimize frictional heat. Polishing may also be performed by hand without machines; however, no emissions occur from hand polishing.

Machining Operations.

This metal fabrication and finishing operation includes activities such as turning, milling, drilling, boring, tapping, planing, broaching, sawing, cutting, shaving, shearing, threading, reaming, shaping, slotting, hobbing, and chamfering, where stock is removed from a work piece as chips by a machine that forces a cutting piece against a work piece. Shearing operations cut materials into a desired shape and size, while forming operations bend or conform materials into specific shapes. Cutting and shearing operations include punching, piercing, blanking, cutoff, parting, shearing and trimming. Forming operations include bending, forming, extruding, drawing, rolling, spinning, coining, and forging the metal. Machining is usually totally enclosed, where the enclosure is part of the operating equipment. Many of these machining operations use lubricants or liquid coolants either alone or in conjunction with enclosures.

Painting Operations.

Paints and coatings (hereafter called “paints”) are applied to metal fabrication and finishing products for surface protection, aesthetics, or both. Painting or coating (hereafter called “painting”) is usually performed using a spray gun in a spray booth or with portable spray equipment. Paints may also be applied via dip tanks. The coated parts then pass through an open (flashoff) area where additional volatiles evaporate from the paint. The coated parts may pass through a drying/curing oven, or are allowed to air dry, where the remaining volatiles are evaporated.

Spray-applied painting operations include any hand-held device that creates an atomized mist of paint and deposits the paint on a substrate. For the purposes of this rule, spray-painting does not include thermal spray operations, also known as metallizing, flame spray, plasma arc spray, and electric arc spray, among other names, in which solid metallic or non-metallic material is heated to a molten or semi-molten state and propelled to the work piece or substrate by compressed air or other gas, where a bond is produced upon impact. Thermal spraying operations at area sources are subject to the Plating and Polishing Area Source NESHAP, subpart WWWWWW of this part.

Spray gun cleaning may be done by hand cleaning parts of the disassembled gun in a container of solvent, by flushing solvent through the gun without atomizing the solvent and paint residue, or by using a fully enclosed

spray gun washer. A combination of non-atomizing methods may also be used. A gun washer consists of a solvent reservoir and a covered enclosure that dispenses solvent for gun cleaning. The enclosure may also hold the gun for automated gun cleaning. During gun cleaning in a gun washer, the cleaning solvent is dispensed from the reservoir and sprayed through the gun while it is open.

Welding Operations.

This metal fabrication and finishing operation joins two metal parts by melting the parts at the joint and filling the space with molten metal. The most frequently used method for generating heat is obtained either from an electric arc or a gas-oxygen flame. The type of welding most commonly used in the metal fabrication and finishing source categories is thought to be electric arc welding.

Electric arc welding includes many different variations that involve various types of electrodes, fluxes, shielding gases, and types of equipment. Electric arc welding can be divided into that which uses consumable electrodes vs. nonconsumable electrodes. In electric arc welding, a flow of electricity across the gap from the tip of the welding electrode to the base metal creates the heat needed for melting and joining the metal parts. The electric current melts both the electrode and the base metal at the joint to form a molten pool, which solidifies upon cooling. Consumable welding rods are used when extra metal is needed as a filler for the joint to make a complete bond. The consumable rods must be close in composition to the base metals, and can vary with each application. An externally supplied gas (argon, helium, or carbon dioxide) can be used to shield the arc.

2. Metal Fabrication and Finishing HAP Emission Sources

All five of the metal fabrication and finishing operations described above can emit MFHAP. The MFHAP that can be emitted from the metal fabrication and finishing operations are in the form of particulate matter (PM) produced from the material being fabricated, PM emitted from the use of consumable welding rods, and MFHAP used to color paints (as pigments). In addition, there are VOHAP emitted from painting operations, where the VOHAP are used as vehicles and solvents for the paints. Details on the HAP emissions from each of the five potential HAP-emitting operations follow below.

Dry Abrasive Blasting Emissions.

The emissions from dry abrasive blasting are predominantly inert PM resulting from breakdown of the blast material which is composed of silica sand, glass beads, aluminum oxide, slag, garnet, steel shot, walnut shells, and other materials. Few if any blast materials contain MFHAP, therefore any MFHAP that is emitted from blasting would originate from the part or product being blasted. Occasionally the blasted part or product may be painted, in which case the PM will contain additional MFHAP if present in the pigments in the paint. Painted substrates are uncommon in the metal fabrication and finishing industries, since these industries primarily produce new products rather than recondition old ones. The blasted substrates typically include metals such as: Cadmium, chromium (primarily in stainless steel), iron, lead, magnesium, manganese (in both mild and stainless steels), mercury, molybdenum, nickel (in stainless steel), selenium, tin, vanadium, and zinc (in galvanized steel). All five MFHAP are potential components of blasting substrates.

Dry Grinding and Dry Polishing Emissions.

Some metal fabrication and finishing machine operations, such as grinding and polishing, are often times dry operations which can emit PM that can contain MFHAP. Polishing by hand without the use of machines usually emits little or no PM or MFHAP due to the low level of abrasion that potentially can be induced by the worker's hands. All the PM or MFHAP in grinding and polishing is produced from the work piece itself. Thus, the composition of the PM and presence of MFHAP is dependent upon the metal being worked. As above for blasting, the metal fabrication and finishing substrates typically include metals such as: Cadmium, chromium (primarily in stainless steel), iron, lead, magnesium, manganese (in both mild and stainless steels), mercury, molybdenum, nickel (in stainless steel), selenium, tin, vanadium, and zinc (in galvanized steel). All five MFHAP are potential components of metal fabrication and finishing substrates and therefore, are also potential emissions from operations of dry grinding and dry polishing with machines.

Machining Emissions.

Most of the machining operations in the metal fabrication and finishing industry are totally enclosed, where the enclosure is part of the equipment. Many of these operations use lubricants or liquid coolants, either alone or in conjunction with enclosures. Because any emissions generated by these machining operations, which would be in the form of PM, are captured or entrained in the liquid, little or no emissions are generated. Any MFHAP that is released from machining would originate from the part or product being machined.

Spray Painting Emissions.

The sources of HAP emissions from spray painting operations are the metal pigments and solvents that are in the paints. A substantial fraction of paint that is atomized does not reach the part and becomes what is termed “overspray” and generates HAP emissions.

All five MFHAP are potential components of paint pigments that are used to provide color to the paint. The MFHAP are emitted when the paints are atomized during spray application. The proposed spray painting requirements of this proposed rule would only apply to those spray painting operations that spray-apply paints that contain MFHAP. Paints are considered to contain MFHAP if they contain any individual MFHAP at a concentration greater than 0.1 percent by mass. For the purpose of determining whether paints contain MFHAP, facilities would be able to use formulation data provided by the manufacturer or supplier, such as the material safety data sheet, as long as it represents each MFHAP compound in the paint that is present at 0.1 percent by mass or more for Occupational Safety and Health Administration (OSHA)-defined carcinogens and at 1.0 percent by mass or more for other MFHAP compounds.

Paint solvents are used as vehicles for the paint pigments. These solvents include VOHAP such as xylenes, toluene, phenol, cresols/cresylic acid, glycol ethers (including ethylene glycol monobutyl ether), styrene, methyl isobutyl ketone, and ethyl benzene. Paints used in spray painting are thinned with solvents so that the paints are fluid enough to be able to be delivered onto the parts and products via narrow spray gun nozzles. The solvents are considered to be completely volatilized during spray application of the paint and during curing or drying. Most solvents contain HAP. The solvents may also consist of volatile organic compound (VOC) emissions which contribute to ozone formation, an EPA-regulated criteria pollutant.

The remaining HAP emissions are primarily from cleaning operations, such as cleaning of spray guns. The HAP emissions from both the cleaning solvent and the paint removed from the gun can be emitted during cleaning. Solvents used for equipment cleaning may contain the same HAP as the paints they remove. The HAP Emissions from gun cleaning are minimized when cleaning is performed in a manner such that an atomized mist or spray of gun cleaning solvent and paint residue is not created outside of a container that collects used gun cleaning solvent.

Mixing and storage are other sources of HAP emissions. The HAP emissions can occur from displacement of HAP-laden air in containers used to store HAP solvents or to mix paints containing HAP solvents. The displacement of vapor-laden air also can be caused by changes in temperature or barometric pressure, or by agitation during mixing.

Welding Emissions.

The type of welding most commonly used in the metal fabrication and finishing source categories is thought to be electric arc welding. This is also the type of welding that can produce the most MFHAP emissions, since a consumable electrode is used. Emissions from welding are in the form of a fume, which is defined to be particles that are small enough to be airborne for extended periods of time and are visible to the human eye. The size of particles in welding fume is highly variable with an average size around 1 micrometer (μm), corresponding to what is commonly called the “fume” size range. Welding fumes have a bimodal distribution, with maximum concentrations in “coarse” (approximately 1.5 μm) and “fine” (0.52 μm) particle size ranges.

Welding fumes are a product of the base metal being welded, the consumable welding electrode or wire, the shielding gas, and any surface coatings or contaminants on the base metal. As much as 95 percent of the welding fume is thought to originate from the melting of the electrode or wire consumable. Welding fume constituents may include silica and fluorides, used to aid the welding operation, and HAP metals such as antimony, arsenic, beryllium, cobalt, mercury, and selenium, in addition to the five MFHAP: Cadmium, chromium, lead, manganese, and nickel. As noted above for dry abrasive blasting, chromium and nickel are found primarily in stainless steel, whereas manganese is found in both mild and stainless steels.

Among the electric arc welding operations that use a consumable electrode, shielded metal arc welding (SMAW) is used in more than 50 percent of welding. SMAW also was the first welding type to use a consumable electrode and suits most general purpose welding applications. SMAW, also called manual metal arc welding (MMAW) or “stick” possibly because it uses replaceable welding electrode rods that look like sticks, has a high fume formation rate as compared to other welding operations. The advantages of SMAW welding include its simplicity, low cost, portability, and the fact that a shielding gas is not needed. One restriction of SMAW is that since it uses metal rods that must be replaced, it is slower than the welding operations which use continuous electrodes.

Another type of welding that uses a consumable electrode and has a high fume formation rate is fluxed-core arc welding (FCAW). High fume formation occurs because the weld material is a liquid or “flux” and not a solid wire, and therefore is more volatile.

Gas metal arc welding (GMAW), originally called metal inert gas (MIG) welding because it used an inert gas for shielding, has a moderate fume formation rate as compared to other welding operations. The advantages of GMAW include its ability to be operated in semiautomatic or automatic modes. It is the only consumable welding type that can weld all commercially important metals, such as carbon steel, high-strength low alloy steel, stainless steel, nickel alloys, titanium, aluminum, and copper. With GMAW, a weld can be performed in all positions with the proper choice of electrode, shielding gas, and welding variables. Compared to SMAW, the rate of deposition of the electrode material and therefore welding rate is higher than with GMAW. The disadvantage is that the equipment for GMAW is more complex, more expensive, and less portable than SMAW.

Another type of welding that uses a consumable electrode and has a low fume formation rate is submerged arc welding (SAW). In this type of welding, the welding rod is not exposed to the atmosphere which lowers the potential for emissions.

Two welding operations that use non-consumable electrodes are gas tungsten arc welding (GTAW) that is also called tungsten inert gas (TIG), and plasma arc welding (PAW). Because consumable electrodes are not used, this type of welding has low or no emissions.

The choice of welding method is determined by many variables that include but are not limited to substrate material and shape; type of weld needed; skill of welder; and amount of welding to be done, therefore, a change from one type of welding to another is not always possible.

The shape of the material is another variable that can affect fume formation rate. It also has been found that when the angle of welding is closer to 90°, lower fume formation occurs. If the shape of the part to be welded prevents re-positioning the welding equipment, this pollution prevention technique also cannot be used.

In terms of welding rod feed rate, it has been found that the higher the wire feed rate the higher the fume formation rate. Also, a low fume welding rod that reduces fume by 30 percent as compared to other available products has been reported as recently available for use with FCAW. Minor effects to reduce fume formation rate have also been attributed to the speed that the welding torch moves along the weld, i.e., the “travel speed.”

Carrier or shielding gas type and flow rate are also variables that have been found to affect welding fume formation rate. Substitution of argon gas reduces the fume formation rate. A reduction in fume of approximately 40 percent has been reported if argon is replaced as the shielding gas. The shield gas flowrate also can be optimized, with 35 cubic feet per hour the reported optimum rate. This rate is in the middle of the usual operating range and is thought to be low enough to minimize turbulence but high enough to protect the worker.

Voltage and current play a key role in the welding fume formation rate. While low voltage and/or current is known to lower the fume formation rate, the use of a pulsed current has been found to lower fume formation by up to 90 percent of the rate with straight current for some types of welding operations. The reduction in welding fume with a pulsed current is due to the change in metal electrode transfer mode from globular to spray, that results from moderately increasing the voltage and delivering a pulsed rather than steady current. There is also a voltage window in which the fume rate reduction occurs, since with too high voltage, a shift from spray to stream mode occurs along with a subsequent increase in emissions. Pulsed current is only successful if used with GMAW, which is itself a pollution prevention technique since it has one of the lowest fume formation rates of welding performed with consumable electrodes.

Welding emissions have been found to be reduced when automation is used. Since automated welding is faster and more efficient than manual welding, total emissions are lower even though the overall fume formation rate of the automated welding remains the same as with manual welding.

Emissions of MFHAP in welding fume are also subject to regulations by the OSHA, a U.S. government agency that develops work place emission standards. The sole goal of OSHA regulations is to protect the worker from being exposed to high concentrations of pollutants, such as MFAP. The OSHA regulations set standards for MFHAP concentration as measured in the breathing zone of the workers, as a time-weighted average over the time period of a typical work shift (usually 6 hours

or more). The OSHA limits for MFHAP are as follows:

Welding MFHAP

OSHA limit

(micrograms per cubic meter)

cadmium fume

5

chromium, hexavalent

5

chromium, total metal

1,000

lead

50

manganese

5,000

nickel

1,000

The OSHA hexavalent chromium exposure limit was reduced in 2006 from 52 to 5 micrograms per cubic meter (μg/m

3

). The American Conference of Government Industrial Hygienists, an association of occupational health professionals, recommends a worker exposure limit for “total welding fume” of 5,000 μg/m

3

.

3. Metal Fabrication and Finishing HAP Emission Controls

A variety of methods is used to control emissions from the metal fabrication and finishing operations. Some methods are designed to reduce emissions through pollution prevention or management practices, and other methods involve capturing emissions and exhausting them to an add-on emission control device. The most widely-used methods of control employed by the metal fabrication and finishing operations are discussed below.

Dry Abrasive Blasting Controls.

Small self-contained “glove box” dry abrasive blasting operations are used for small parts and typically have no vents to the atmosphere, thus no emissions. These devices are considered controlled operations as typically operated. When using glove boxes, the worker places their hands in openings or gloves that extend into the box and enables the worker to hold the objects as they are being blasted without allowing air and blast material to escape the box. Because of the proximity of the worker to the glove box and the blasting operation, no abrasive material can be allowed to be emitted.

Larger dry abrasive blasting operations are performed in enclosures and are typically equipped with cartridge filters or other external add-on control devices that collect degraded or “used” blast material and particles removed from the parts or products. These control systems, which consist of enclosures and filters, can achieve at least 95 percent control of PM, as a surrogate for MFHAP, if operated according to the manufacturer's specifications. Used blast material is recycled via screening, sieving, or other methods to remove degraded media and return the blast material to its original condition. Significant cost savings are realized through recycling of the blast material. Some dry abrasive blasting operations are not completely enclosed, or are performed outdoors. Emissions from these operations are controlled or reduced via partial enclosures and also the use of management practices. These practices include good choice of blast media which is less likely to break down into fine PM; avoiding re-use of blast media, or filtration of blast media to remove broken particles; and avoiding blasting outside during periods of high winds.

Dry Grinding and Dry Polishing with Machines Controls.

These machine operations emit significant metal PM if uncontrolled, therefore, these operations, if not totally enclosed, use control systems to control the PM emitted. The control systems are composed of local capture devices with cartridge, fabric, or high-efficiency particulate air (HEPA) filters as control devices. These control systems are known to achieve 85 percent overall control of PM, as a surrogate for MFHAP, considering the efficiency of both the capture and control devices. The large amount of fine PM generated during these operations would make the work environment unbearable for the workers if not controlled, hence constant PM control is standard industry practice and an integral part of all dry grinding and dry polishing with machine operations at metal fabrication and finishing facilities.

Machining Controls.

The MFHAP emitted by machining operations consist of large particles or metal shavings that are so large they immediately fall to the floor. The machines used today to perform precision cutting and forming are totally enclosed except for doors that open to allow placement of the part to be machined. The doors are closed before the machining begins; therefore, no MFHAP or PM is emitted into the workplace during machining operations. Some machining operations also use lubricants and cutting oils to keep the equipment cooled and working properly and, therefore, concurrently entrain any fine particles that are generated. These “wet” machining operations also do not generate any MFHAP or PM emissions during operation. This industry has evolved since 1990, where machining operations were open and a large source of PM and MFHAP, to the current industry practice of totally enclosing the machining operations.

Spray Painting Controls.

There are three primary means of controlling emissions from painting operations: Reduction of overspray; capture of overspray with a spray booth and control of the MFHAP by filtration or a water scrubbing system; and changes to paint composition to reduce solvent and VOHAP content.

Reduction of overspray can have a significant effect on emissions of both MFHAP and VOHAP. The fraction of applied paint that becomes overspray depends on many variables, but two of the most important are the type of equipment and the skill of the painter. High velocity low pressure spray guns or other high-efficiency technologies, such as airless spray guns or electrostatic technologies, can significantly reduce the amount of overspray, and thus reduce emissions. Worker training is particularly important with these technologies, because they require even experienced painters to learn new techniques. Many types of training programs are available and many facilities perform their own training “in-house.” The best known of the external training programs is the Spray Technique Analysis and Research (STAR®) program study that originated at the University of Northern Iowa Waste Reduction Center and has now been adopted at 37 locations (primarily community colleges) throughout the United States.

Some overspray lands on surfaces of the spray booth and the masking paper that is usually placed around the surface being sprayed, but the rest of the overspray is contained by the spray booth and drawn into the spray booth exhaust system. The large amount of PM generated during paint spraying makes it necessary to control the PM emitted at all times to protect the worker and working environment. If the spray booth has filters, most of the overspray PM and metals are captured by the filters; otherwise, the emissions are exhausted to the atmosphere. Spray booths controlled by fabric filters can reduce PM and MFHAP emissions by 98 percent, if operated properly. Water curtains can also be used for controlling emissions from spray booths.

As a result of efforts to reduce the impact of HAP- and VOC-containing paint solvents on the environment, many paint manufacturers have developed lower solvent-content paints, also referred to as “water-based” paints. Water-based paints may have up to 30 percent VOHAP-containing solvent, with the balance of the paint vehicle consisting of water; however, the level of solvent in water-based paints is much less than the previous 80 percent or

more VOHAP that is contained in solvent-based paints. As a result of the lower VOHAP solvent content, water-based paints in general have a lower VOHAP content than solvent-based paints. The regulations promulgated to fulfill section 112 of the CAA for major sources had a direct effect on increasing the market availability of lower-HAP and -VOC paints in all market areas, including miscellaneous metal parts, plastic parts, large appliances, autobody refinishing, and architectural and industrial maintenance coatings. Many State air toxics regulations require the use of commonly called “compliant coatings,” where the only paints or coatings allowed to be used in certain areas must contain a solvent content lower than a designated level in order to be “compliant” with the regulation. The use of compliant coatings is a pollution prevention control method.

Some regulations which require compliant coatings set one limit for all paints while others require different limits depending on the purpose of the paint. Other regulations permit a weighted averaging of the solvent content of the paints used, where facilities are permitted to use paints with higher solvent contents as long as their use is offset by paints with lower solvent content. This latter method of compliance is considered a more flexible approach that allows facilities to balance their use of solvents to where it is needed most. In addition, some facilities may choose to use add-on controls such as solvent recovery units, thermal incineration, or carbon absorbers to control VOHAP emissions for situations where the solvent content cannot be reduced to a compliant coating level. These add-on controls are known to achieve at least 95 percent control of VOHAP.

Welding Controls.

Many different welding operations are commonly used in the metal fabrication and finishing industry, as discussed above under welding emissions. Consequently, there are many possible means of reducing emissions. Not all control methods are appropriate for all types of welding operations, however, and thus there is no one “best” method to reduce welding fume or PM, as a surrogate for MFHAP. The two primary categories of emission control for welding are fume reduction through pollution prevention and management practices, and capture and control of the welding fume.

The primary variable in pollution prevention for welding is the type of welding wire or electrode used. Over 95 percent of welding fume is thought to originate from the filler or electrode material with the remainder coming from the base material. If the wire consists of MFHAP-containing material, such as chromium or nickel, then the emissions of these MFHAP are more likely. Since the weld or wire material must closely match the material being welded in order to be effective, the choice of weld material may not be able to be altered by the facility for some or all of its products. For example, if stainless steel is a required material due to the specifications of the part or product by the customers, the potential for chromium emissions in these operations cannot be prevented.

The choice of welding type, which impacts the potential fume formation rate, also provides opportunities for pollution prevention. The type of welding method used at metal fabrication and finishing facilities is determined by many variables that include but are not limited to substrate material and shape; type of weld needed; skill of welder; and amount of welding to be done. Therefore, a change from one type of welding to another is not always possible.

Welding which does not use a consumable electrode has a much lower emission potential, as noted above in the “Welding Emissions” discussion. Two common welding operations that use non-consumable electrodes are GTAW, also called TIG, and PAW. Switching from welding that uses a consumable electrode to one of the above operations that does not use a consumable electrode is a form of pollution prevention.

Among the welding operations that use a consumable electrode, SMAW, also called MMAW or “stick,” is the most widely used electric arc welding. However, SMAW has a high fume formation rate as compared to other welding operations. Another welding type that also has a high fume formation rate is FCAW. GMAW, also called MIG, has a moderate fume formation rate as compared to other welding operations. The disadvantage of GMAW is that the equipment for GMAW is more complex, more expensive, and less portable than SMAW. Another type of welding that uses consumable electrodes and has a relatively lower fume formation rate is SAW. Switching from welding that has a relatively higher fume formation rate, such as SMAW or FCAW, to one that has a lower rate, such as GMAW or SAW, is a form of pollution prevention.

Other welding variables have been determined to have a favorable effect on fume formation rates. Optimizing these variables for the specific task at hand is a form of pollution prevention. These variables include optimized welding rod feed rate, use of low fume welding rods; fast welding torch travel speed; optimized carrier or shielding gas flow rate; substitution of inert shielding gas, such as argon, for carbon dioxide shielding gas; lowering the welding voltage; pulsing the applied current; and the use of automation, i.e., robotics. Note that pulsing the current is only successful if used with GMAW, which is itself a pollution prevention technique since it has one of the lowest fume formation rates for welding performed with consumable electrodes.

In addition to the numerous management and pollution prevention practices that reduce welding fume generation, some facilities use capture and control devices to collect welding fume after it is generated. Hoods and other local exhaust techniques are used to collect the welding fume which is then vented to cartridge, fabric, or HEPA filters. Some of these control systems may only partially capture the welding fume. The advantage of using local capture systems as opposed to room ventilation is that it provides the ability to move the control device to different welding stations as needed. Very few facilities in the metal fabrication and finishing source categories use full room ventilation and PM control to reduce welding emissions. This is due to the competing requirements to ventilate the breathing zone of the worker to comply with OSHA regulations and the need to minimize the amount of exhaust air going to ventilation and add-on control devices.

The use of control systems is not always possible because the capture systems may affect the air flow pattern around welding operations and, therefore, interfere with the success of the weld. Another difficulty with local exhaust is the need to position and sometimes reposition the capture equipment so as to be most effective during welding operations without causing more fumes to enter the breathing zone of the worker.

Fume control welding guns, commonly called fume guns, have been developed where the welding fume is captured by the same device that performs the welding. Mixed success has been reported with these devices because of problems with the ergonomics of using the fume guns.

In the EPA survey of metal fabrication and finishing facilities, only 20 percent of facilities with welding stations used controls devices or fume guns. These control systems are known to achieve 85 percent overall PM control efficiency, as a surrogate for MFHAP, considering the efficiency of both the capture and control devices.

III. Summary of Proposed Standards

A. Do the proposed standards apply to my source?

The proposed subpart XXXXXX applies to new or existing affected metal fabrication and finishing area sources in one of the following nine source categories (listed alphabetically) that emit MFHAP: (1) Electrical and Electronic Equipment Finishing Operations; (2) Fabricated Metal Products; (3) Fabricated Plate Work (Boiler Shops); (4) Fabricated Structural Metal Manufacturing; (5) Heating Equipment, except Electric; (6) Industrial Machinery and Equipment: Finishing Operations; (7) Iron and Steel Forging; (8) Primary Metal Products Manufacturing; and (9) Valves and Pipe Fittings. A more detailed description of these source categories can be found in section II(B) above. If you have any questions regarding the applicability of this action to a particular entity, consult either the air permit authority for the entity or your EPA regional representative as listed in 40 CFR 63.13 of subpart A (General Provisions). Facilities affected by this proposed rule are not subject to the miscellaneous coating requirements in 40 CFR part 63, subpart HHHHHH, “National Emission Standards for Hazardous Air Pollutants: Paint Stripping and Miscellaneous Surface Coating Operations at Area Sources,” for their source(s) subject to the requirements of this proposed rule. There potentially may be other sources at the facility not subject to the requirements of this proposed rule that are instead subject to subpart HHHHHH of this part.

B. When must I comply with these proposed standards?

All existing area source facilities subject to this proposed rule would be required to comply with the rule requirements no later than 2 years after the date of publication of the final rule in the

Federal Register

.

C. For what processes is EPA proposing standards?

In our research for this proposed rule, we found that there are five general production operations common to the nine metal fabrication and finishing source categories that can emit MFHAP. These five production operations are: (1) Dry abrasive blasting; (2) dry grinding and dry polishing with machines; (3) machining; (4) spray painting; and (5) welding. In our review of the available data, we observed significant differences for some of the five metal fabrication and finishing operations. As explained below, as the result of these differences we have further differentiated some of the above five operations. We identify below nine distinct metal fabrication and finishing processes for the purposes of this proposed rule.

For dry abrasive blasting operations, we determined that there were two distinct sizes of products being blasted that affected the manner in which the blasting was performed: products more than 8 feet in any dimension, and products equal to or less than 8 feet. For products under 8 feet, we also observed that some of these products were blasted in completely enclosed chambers that did not allow any air or emissions to escape. Therefore, we developed three distinct dry abrasive blasting processes: (1) Dry abrasive blasting of objects less than or equal to 8 feet in any dimension in completely enclosed and unvented blast chambers; (2) dry abrasive blasting of objects less than or equal to 8 feet in any dimension performed in vented enclosures, and (3) dry abrasive blasting of objects greater than 8 feet in any dimension.

In spray painting operations that emit MFHAP, we also determined that there were two distinct sizes of products being painted that affected the manner in which the process was performed: products more than 15 feet in any dimension, and products equal to or less than 15 feet in any dimension. Therefore we developed two distinct spray painting processes: (1) Spray painting of objects less than or equal to 15 feet in any dimension, and (2) spray painting of objects greater than 15 feet in any dimension. However, for the purposes of controlling VOHAP, we did not distinguish between object size, therefore the standards proposed for control of VOHAP emissions from spray painting includes only one proposed GACT requirement.

For dry grinding and dry polishing with machines, machining, and welding, we did not observe any distinct differences that would warrant further distinguishing the operations into separate processes. Therefore, these three processes combined with the three for dry abrasive blasting and three for painting results described above, results in nine total processes addressed by this proposed rule, as follows: (1) Dry abrasive blasting objects less than or equal to 8 feet in any dimension, performed in completely enclosed and unvented blast chambers; (2) dry abrasive blasting of objects less than or equal to 8 feet in any dimension, performed in vented enclosures; (3) dry abrasive blasting of objects greater than 8 feet in any dimension; (4) dry grinding and dry polishing with machines; (5) machining; (6) control of VOHAP from spray painting; (7) control of MFHAP in the spray painting of objects less than or equal to 15 feet in any dimension; (8) control of MFHAP in the spray painting of objects greater than 15 feet in any dimension; and (9) welding.

D. What emissions control requirements is EPA proposing?

We are proposing control requirements for nine metal fabrication and finishing processes described above in section (C). The following is a description of these proposed control requirements. The emission control requirements proposed here do not apply to tool or equipment repair; or research and development operations.

1. Standards for Dry Abrasive Blasting of Objects Less Than or Equal To 8 Feet in Any Dimension, Performed in Completely Enclosed and Unvented Blast Chambers

Completely enclosed and unvented blast chambers are generally small “glove box” type dry abrasive blasting operations. Because there are no vents or openings in the enclosures, there are no emissions directly from the operation itself.

This proposed rule would require owners or operators of completely enclosed and unvented blast chambers to comply with the following two management and pollution prevention practices: (1) Minimize dust generation during emptying of the enclosure; and (2) operate all equipment used in the blasting operation according to manufacturer's instructions.

2. Standards for Dry Abrasive Blasting of Objects Less than or Equal to 8 Feet in Any Dimension, Performed in Vented Enclosures

This proposed rule would require owners or operators of affected new and existing dry abrasive blasting operations blasting substrates of less than or equal to 8 feet in any dimension to perform blasting with a control system that includes an enclosure, as a capture device, and a cartridge, fabric or HEPA filter as a control device that is designed to control PM emissions, as a surrogate for MFHAP, from the process. These control systems using filters can achieve at least 95 percent control efficiency of PM, as a surrogate for MFHAP, if operated according to the manufacturer's specifications.

An enclosure is defined to be any structure that includes a roof and at least two complete walls, with side curtains and ventilation as needed to insure that no air or PM exits the chamber while blasting is performed. Apertures or slots may be present in the

roof or walls to allow for transport of the blasted objects using overhead cranes, or cable and cord entry into the blasting chamber. Facilities that would like to use equipment other than those listed above can seek approval to do so pursuant to the procedures in § 63.6(g) of the General Provisions to part 63, which require the owner or operator to demonstrate that the alternative means of emission limitation achieves at least equivalent HAP emission reductions as the controls specified in this proposed rule.

This proposed rule also would require owners or operators of all affected new and existing dry abrasive blasting operations blasting substrates of less than or equal to 8 feet in any dimension to comply with the following three management and pollution prevention practices: (1) Keep work areas free of excess dust by regular sweeping or vacuuming to control the accumulation of dust and other particles; regular sweeping or vacuuming is defined to be sweeping or vacuuming conducted once per day, once per shift, or once per operation as needed, depending on the severity of dust generation; (2) enclose dusty material storage areas and holding bins, seal chutes and conveyors; and (3) operate all equipment according to manufacturer's instructions.

3. Standards for Dry Abrasive Blasting of Objects Greater Than 8 Feet in Any Dimension

This proposed rule would require owners or operators of affected new and existing dry abrasive blasting operations that blast substrates greater than 8 feet in any dimension to comply with the following management and pollution prevention practices to minimize MFHAP emissions from the processes: (1) Do not perform blasting outside when wind velocity is greater than 25 miles per hour; (2) switch from high PM-emitting blast media (e.g., sand) to low PM-emitting blast media (e.g., steel shot, aluminum oxide), whenever practicable; (3) do not blast substrates having coatings containing lead (>0.1 percent lead), unless enclosures, barriers, or other PM control methods are used to collect the lead particles; and (4) do not re-use the blast media unless contaminants (i.e., any material other than the base metal, such as paint residue) have been removed by filtration or screening so that the abrasive material conforms to its original size and makeup.

This proposed rule would also require owners or operators of affected dry abrasive blasting operations that blast substrates greater than 8 feet in any dimension to comply with the following three management and pollution prevention practices: (1) Keep work areas free of excess dust by regular sweeping or vacuuming to control the accumulation of dust and other particles; regular sweeping or vacuuming is defined to be sweeping or vacuuming conducted once per day, once per shift, or once per operation as needed, depending on the severity of dust generation; (2) enclose dusty material storage areas and holding bins, seal chutes and conveyors; and (3) operate all equipment according to manufacturer's instructions.

4. Standards for Dry Grinding and Dry Polishing With Machines

Dry grinding and dry polishing with machines operations often emit significant PM, which is a surrogate for MFPM. This proposed rule would require owners or operators of affected new and existing dry grinding and dry polishing with machines operations to capture PM emissions, as a surrogate for MFHAP, with capture devices and vent the exhaust to a cartridge, fabric, or HEPA filter. These control systems are known to achieve at least 85 percent overall PM control efficiency, as a surrogate for MFHAP, if operated according to the manufacturer's specifications. Facilities that would like to use equipment other than those listed above can seek approval to do so pursuant to the procedures in § 63.6(g) of the General Provisions to part 63, which require the owner or operator to demonstrate that the alternative means of emission limitation achieves at least equivalent HAP emission reductions as the controls specified in this proposed rule.

This proposed rule would also require owners or operators of affected new and existing dry grinding and dry polishing with machines operations to comply with the following two management and pollution prevention practices: (1) Keep work areas free of excess dust by regular sweeping or vacuuming to control the accumulation of dust and other particles; regular sweeping or vacuuming is defined to be sweeping or vacuuming conducted once per day, once per shift, or once per operation as needed, depending on the severity of dust generation; and (2) operate all equipment used in dry grinding and dry polishing with machines according to manufacturer's instructions.

5. Standards for Machining

The majority of the PM released by machining operations consists of large particles or metal shavings that fall immediately to the floor. Any MFHAP that is released would originate from the part or product being machined. Machining is totally enclosed and/or uses lubricants or liquid coolants that do not allow small particles to escape. This proposed rule would require owners or operators of affected new and existing machining operations to comply with the following two management and pollution prevention practices to minimize dust generation in the workplace: (1) Keep work areas free of excess dust by regular sweeping or vacuuming to control the accumulation of dust and other particles; regular sweeping or vacuuming is defined to be sweeping or vacuuming conducted once per day, once per shift, or once per operation as needed, depending on the severity of dust generation; and (2) operate equipment used in machining operations according to manufacturer's instructions.

6. Standards for Control of VOHAP from Spray Painting Operations

Spray painting operations can be significant sources of VOHAP emissions. This proposed rule would require owners or operators of spray painting operations from affected sources that have the potential to emit VOHAP to use paints containing no more than 3.0 pounds VOHAP per gallon paint solids (0.36 kilograms per liter (kg/liter)) on an annual (12-month) rolling average basis. Two methods of complying with this standard are provided. One option would require that all paints are demonstrated as meeting the VOHAP limit. The second option would require facilities to meet the VOHAP limit using a 12-month rolling weighted average. In this second option, some paints can be above the VOHAP limit as long as their use is balanced by other paints that are below the limit, such that the overall weighted average of all paints and their VOHAP content is calculated to be at or below the VOHAP limit that would be required by this proposed rule.

This proposed rule would also require owners or operators of new and existing spray painting operations that have the potential to emit VOHAP to comply with the following two management and pollution prevention practices: (1) Minimize VOHAP emissions during mixing, storage, and transfer of paints; and (2) keep paint and solvent lids tightly closed when not in use.

Based on reasonable assumptions about the practices included in the 1990 112(k) urban HAP inventory, we have concluded that painting processes that contributed to VOHAP and MFHAP emissions in these source categories most likely did not include the following materials or activities and,

therefore, we do not cover these materials or activities in this proposed rule:

(1) Paints applied from a hand-held device with a paint cup capacity that is less than 3.0 fluid ounces (89 cubic centimeters);

(2) Surface coating application using powder coating, hand-held, non-refillable aerosol containers, or non-atomizing application technology, including, but not limited to, paint brushes, rollers, hand wiping, flow coating, dip coating, electrodeposition coating, web coating, coil coating, touch-up markers, or marking pens;

(3) Any painting or coating that normally requires the use of an airbrush or an extension on the spray gun to properly reach limited access spaces; or the application of paints or coatings that contain fillers that adversely affect atomization with high velocity low pressure (HVLP) or equivalent spray guns, and the application of coatings that normally have a dried film thickness of less than 0.0013 centimeter (0.0005 in.).

7. Standards for Control of MFHAP from Spray Painting of Objects Greater Than 15 Feet in Any Dimension

This proposed rule would require owners or operators of affected new and existing spray painting of objects greater than 15 feet in any dimension to comply with one equipment standard, to use of low-emitting and pollution preventing spray gun technology. This proposed rule also would require two management practices: (1) Spray painter training and (2) spray gun cleaning.

Based on reasonable assumptions about the practices included in the 1990 112(k) urban HAP inventory, we have concluded that painting processes that contributed to MFHAP emissions in these source categories most likely did not include the following materials or activities, and, therefore, we do not cover these materials or activities in this proposed rule:

(1) Paints applied from a hand-held device with a paint cup capacity that is less than 3.0 fluid ounces (89 cubic centimeters);

(2) Surface coating application using powder coating, hand-held, non-refillable aerosol containers, or non-atomizing application technology, including, but not limited to, paint brushes, rollers, hand wiping, flow coating, dip coating, electrodeposition coating, web coating, coil coating, touch-up markers, or marking pens;

(3) Any painting or coating that normally requires the use of an airbrush or an extension on the spray gun to properly reach limited access spaces; or the application of paints or coatings that contain fillers that adversely affect atomization with HVLP or equivalent spray guns, and the application of coatings that normally have a dried film thickness of less than 0.0013 centimeter (0.0005 in.).

Spray painting also does not include thermal spray operations, also known as metallizing, flame spray, plasma arc spray, and electric arc spray, among other names, in which solid metallic or non-metallic material is heated to a molten or semi-molten state and propelled to the work piece or substrate by compressed air or other gas, where a bond is produced upon impact. Thermal spraying operations at area sources are subject to the Plating and Polishing Area Source NESHAP, subpart WWWWWW of this part.

Spray Gun Technology Requirements.

This proposed rule would require all affected new and existing facilities using spray-applied paints to use HVLP spray guns, electrostatic application, or airless spray techniques. Alternatively, an equivalent technology can be used if it is demonstrated to achieve transfer efficiency comparable to one of the spray gun technologies listed above for a comparable operation, and for which written approval has been obtained from the Administrator or delegated authority.

The procedure to be used to demonstrate that spray gun transfer efficiency is equivalent to that of an HVLP spray gun should be equivalent to the California South Coast Air Quality Management District's “Spray Equipment Transfer Efficiency Test Procedure for Equipment User, May 24, 1989” and “Guidelines for Demonstrating Equivalency with District Approved Transfer Efficient Spray Guns, September 26, 2002” (incorporated by reference, see § 63.14 of subpart A of this part). The Director of the Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a copy from the California South Coast Air Quality Management District Web site at

http://www.aqmd.gov/permit/docspdf/TransferEfficiencyTestingGuidelinesforHVLPEquivalency.pdf

and

http://www.aqmd.gov/permit/docspdf/Spray-Eqpt-Trfr-Efficiency.pdf.

You may inspect a copy at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to:

http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html

. The proposed requirements of this paragraph do not apply to painting performed by students and instructors at paint training centers.

Spray Painting Training Requirements.

This proposed rule would require all workers that perform spray painting at affected new and existing facilities to be trained, with certification made available that this training has occurred. The painters would need to be certified as having completed classroom and hands-on training in the proper selection, mixing, and application of paints, or the equivalent. Refresher training would need to be repeated at least once every 5 years. These requirements would not apply to operators of robotic or automated surface painting operations. The initial and refresher training would need to address the following topics to reduce paint overspray, which has a direct effect on emissions reductions, as follows:

• Spray gun equipment selection, set up, and operation, including measuring paint viscosity, selecting the proper fluid tip or nozzle, and achieving the proper spray pattern, air pressure and volume, and fluid delivery rate.

• Spray technique for different types of paints to improve transfer efficiency and minimize paint usage and overspray, including maintaining the correct spray gun distance and angle to the part, using proper banding and overlap, and reducing lead and lag spraying at the beginning and end of each stroke.

• Routine spray booth and filter maintenance, including filter selection and installation.

For the purposes of the proposed training requirements, the facility owner or operator may certify that their employees have completed training during “in-house” training programs. Also, facilities that can show by documentation or certification that a painter's work experience and/or training has resulted in training equivalent to the training described above would not be required to provide the initial training required for these painters.

Spray painters have 180 days to complete training after hiring or transferring into a surface painting job from another job in the facility. These proposed training requirements would not apply to the students of an accredited surface painting training program who are under the direct supervision of an instructor who meets the requirements of this paragraph. The training and certification for this rule would be valid for a period not to exceed 5 years after the date the training is completed.

Spray Gun Cleaning Requirements.

This proposed rule would require all paint spray gun cleaning operations at affected new and existing facilities to use an atomized mist or spray such that the gun cleaning solvent and paint residue is not created outside of the container that collects the used gun cleaning solvent. Spray gun cleaning may be done, for example, by hand cleaning of parts of the disassembled gun in a container of solvent, by flushing solvent through the gun without atomizing the solvent and paint residue, or by using a fully enclosed spray gun washer. A combination of these non-atomizing methods above may also be used.

8. Standards for Control of MFHAP From Spray Painting Objects Less Than or Equal to 15 Feet in Any Dimension

This proposed rule would require affected new and existing facilities that are spray painting objects less than or equal to 15 feet in any dimension to comply with two equipment standards: (1) Use of low-emitting and pollution preventing spray gun technology, and (2) use of spray booth PM filters. This proposed rule also would require two management practices: (1) Spray painter training; and (2) spray gun cleaning.

Based on reasonable assumptions about the practices included in the 1990 112(k) urban HAP inventory, we have concluded that painting processes that contributed to MFHAP emissions in these source categories most likely did not include the following materials or activities:

(1) Paints applied from a hand-held device with a paint cup capacity that is less than 3.0 fluid ounces (89 cubic centimeters);

(2) Surface coating application using powder coating, hand-held, non-refillable aerosol containers, or non-atomizing application technology, including, but not limited to, paint brushes, rollers, hand wiping, flow coating, dip coating, electrodeposition coating, web coating, coil coating, touch-up markers, or marking pens;

(3) Any painting or coating that normally requires the use of an airbrush or an extension on the spray gun to properly reach limited access spaces; or the application of paints or coatings that contain fillers that adversely affect atomization with HVLP or equivalent spray guns, and the application of coatings that normally have a dried film thickness of less than 0.0013 centimeter (0.0005 in.).

Spray painting also does not include thermal spray operations, also known as metallizing, flame spray, plasma arc spray, and electric arc spray, among other names, in which solid metallic or non-metallic material is heated to a molten or semi-molten state and propelled to the work piece or substrate by compressed air or other gas, where a bond is produced upon impact. Thermal spraying operations at area sources are subject to the Plating and Polishing Area Source NESHAP, subpart WWWWWW of this part.

Spray Gun Technology Standards.

This proposed rule would require all affected new and existing facilities using spray-applied paints to use HVLP spray guns, electrostatic application, or airless spray techniques. Alternatively, an equivalent technology can be used if it is demonstrated to achieve transfer efficiency comparable to one of the spray gun technologies listed above for a comparable operation, and for which written approval has been obtained from the Administrator or delegated authority.

The procedure to be used to demonstrate that spray gun transfer efficiency is equivalent to that of an HVLP spray gun should be equivalent to the California South Coast Air Quality Management District's “Spray Equipment Transfer Efficiency Test Procedure for Equipment User, May 24, 1989” and “Guidelines for Demonstrating Equivalency with District Approved Transfer Efficient Spray Guns, September 26, 2002” (incorporated by reference, see § 63.14 of subpart A of this part). The Director of the Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a copy from the California South Coast Air Quality Management District Web site at

http://www.aqmd.gov/permit/docspdf/TransferEfficiencyTestingGuidelinesforHVLPEquivalency.pdf

and

http://www.aqmd.gov/permit/docspdf/Spray-Eqpt-Trfr-Efficiency.pdf.

You may inspect a copy at the NARA. For information on the availability of this material at NARA, call 202-741-6030, or go to:

http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html

. The requirements of this paragraph would not apply to painting performed by students and instructors at paint training centers.

Spray Booth PM Control Requirement.

This proposed rule would require the surface preparation stations or spray booths

3

of affected new and existing facilities to be fitted with fiberglass or polyester fiber filters or other comparable filter technology that can be demonstrated to achieve at least 98 percent control efficiency of paint overspray (also referred to as “arrestance”). As an alternate compliance option, spray booths can be equipped with a water curtain, called a “waterwash” or “waterspray” booth.

3

The spray booth roof may contain narrow slots for connecting the parts and products to overhead cranes, or for cord or cable entry into the spray booth.

98 Percent PM Control Filter

—For spray booths equipped with a PM filter, the procedure used to demonstrate filter efficiency would need to be consistent with the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) Method 52.1, “Gravimetric and Dust-Spot Procedures for Testing Air-Cleaning Devices Used in General Ventilation for Removing Particulate Matter, June 4, 1992” (incorporated by reference, see § 63.14 of subpart A of this part). The Director of the

Federal Register

approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a copy from the ASHRAE at 1791 Tullie Circle, NE., Atlanta, GA 30329 or by electronic mail at orders@ashrae.org. You may inspect a copy at the NARA. For information on the availability of this material at NARA, call 202-741-6030, or go to:

http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html

. Compliance with the filter efficiency standard also can be demonstrated through data provided by the filter manufacturer. The test paint for measuring filter efficiency would be a high solids bake enamel delivered at a rate of at least 135 grams per minute from a conventional (non-HVLP) air-atomized spray gun operating at 40 pounds per square inch air pressure; the air flow rate across the filter shall be 150 feet per minute. Affected facilities may use published filter efficiency data provided by filter vendors to demonstrate compliance with this proposed requirement and would not be required to perform this measurement.

Waterwash spray booths

—As an alternative compliance option, spray booths may be equipped with a water curtain that achieves at least 98 percent control of MFHAP. The waterwash or “waterspray” spray booths would be required to be operated and maintained according to the manufacturer's specifications.

Spray Painting Training Requirements.

This proposed rule would require all workers that perform spray painting at affected new and existing facilities to be trained, with certification made available that this training has occurred. The painters would need to be certified as having completed classroom and hands-on

training in the proper selection, mixing, and application of paints, or the equivalent. Refresher training would need to be repeated at least once every 5 years. These requirements would not apply to operators of robotic or automated surface painting operations. The initial and refresher training would need to address the following topics to reduce paint overspray, which has a direct effect on emissions reductions, as follows:

• Spray gun equipment selection, set up, and operation, including measuring paint viscosity, selecting the proper fluid tip or nozzle, and achieving the proper spray pattern, air pressure and volume, and fluid delivery rate.

• Spray technique for different types of paints to improve transfer efficiency and minimize paint usage and overspray, including maintaining the correct spray gun distance and angle to the part, using proper banding and overlap, and reducing lead and lag spraying at the beginning and end of each stroke.

• Routine spray booth and filter maintenance, including filter selection and installation.

For the purposes of the proposed training requirements, the facility owner or operator may certify that their employees have completed training during “in-house” training programs. Also, facilities that can show by documentation or certification that a painter's work experience and/or training has resulted in training equivalent to the proposed training described above would not be required to provide the initial training required for these painters.

Spray painters have 180 days to complete training after hiring or transferring into a surface painting job from another job in the facility. These proposed training requirements do not apply to the students of an accredited surface painting training program who are under the direct supervision of an instructor who meets the requirements of this paragraph. The training and certification for this proposed rule would be valid for a period not to exceed 5 years after the date the training is completed.

Spray Gun Cleaning Requirements

. This proposed rule would require all paint spray gun cleaning operations at affected new and existing facilities to use an atomized mist or spray such that the gun cleaning solvent and paint residue is not created outside of the container that collects the used gun cleaning solvent. Spray gun cleaning may be done, for example, by hand cleaning of parts of the disassembled gun in a container of solvent, by flushing solvent through the gun without atomizing the solvent and paint residue, or by using a fully enclosed spray gun washer. A combination of these non-atomizing methods above may also be used.

9. Standards for Welding

This proposed rule would require owners or operators of affected new and existing welding operations to minimize or reduce welding fume by implementing the following 11 management and pollution prevention practices to be used as practicable:

(a) Use low fume welding processes whenever possible. These welding processes include but are not limited to: GMAW—also called MIG; GTAW—also called TIG; PAW; SAW; and all welding processes that do not use a consumable electrode;

(b) Use shielding gases, as appropriate to the type of welding used;

(c) Use an inert carrier gas, such as argon, as practicable to the type of welding used;

(d) Use low or no-HAP welding materials and substrates;

(e) Operate with a welding angle close to 90°;

(f) Optimize electrode diameter;

(g) Operate with lower voltage and current;

(h) Use low fume wires, as appropriate to the type of welding used;

(i) Optimize shield gas flow rate, as applicable to the type of welding used;

(j) Use low or optimized torch speed; and

(k) Use pulsed-current power supplies, as applicable to the type of welding used.

As a compliance alternative to the management practices for welding processes, facilities may use control systems that reduce at least 85 percent of the welding fume, as a surrogate for MFHAP, with operation of the capture and control devices according to the manufacturer's instructions.

E. What are the initial compliance requirements?

To demonstrate initial compliance with this proposed rule, owners or operators of affected new and existing sources with dry abrasive blasting, machining, dry grinding and dry polishing with machines, spray painting, and welding operations would certify that they have implemented all required management and pollution prevention practices.

In addition, owners or operators of new and existing affected sources with spray painting operations that have the potential to emit VOHAP or MFHAP would also certify that they are in compliance with the following requirements: Limit the VOHAP content of spray-applied paints, use of spray booths and filters, use of approved spray delivery and cleaning systems, and proper training of workers in spray painting application techniques.

F. What are the continuous compliance requirements?

There are continuous requirements for all affected processes in metal fabrication and finishing sources. There are also additional continuous compliance requirements for specific processes or groups of processes, as follows: Visual emissions testing for dry abrasive blasting, machining, and dry grinding and dry polishing with machines; tests for VOHAP content of paints in spray painting; tests for spray painting for MFHAP control; and visual emissions testing for welding. These requirements are discussed below in more detail.

1. Continuous Compliance Requirements for All Sources

This proposed rule would require owners or operators of all affected new and existing sources to demonstrate continuous compliance by adhering to the management and pollution prevention practices specified in this proposed rule and maintaining the appropriate records to document this compliance.

Owners or operators that comply with this proposed rule by operating capture and control systems would be required to operate and maintain each capture system and control device according to the manufacturer's specifications. They also would be required to maintain records to document conformance with this requirement, and to keep the manufacturer's instruction manual available at the facility at all times.

2. Visual Emissions Testing for Dry Abrasive Blasting, Machining, and Dry Grinding and Dry Polishing With Machines, To Determine Continuous Compliance

Visible Emissions Testing

. For new and existing affected sources of dry abrasive blasting operations (except dry abrasive blasting in completely enclosed and unvented blast chambers), machining operations, and dry grinding and dry polishing with machines, this proposed rule would require visible emissions testing to demonstrate continuous compliance with management and pollution prevention practices intended to reduce emissions of PM, as a surrogate for MFHAP.

The affected sources would perform visual determinations of fugitive

emissions, according to the graduated schedule described below, using EPA Method 22 (40 CFR part 60, appendix A) for a period of 15 continuous minutes from the exhaust from either the stack to the control device or the stack from the building where the equipment is located, as applicable. For the purpose of this proposed rule, the presence of visible emissions would be noted if any emissions are observed for more than a total of 6 minutes during the 15-minute period. In case of failure in any Method 22 test, immediate correction action would be required to follow to reduce or eliminate the visible emissions. The affected source would then be required to perform more frequent visible emissions testing, as described in the graduated schedule below.

Graduated Testing Schedule

. The graduated schedule for continuous compliance with visible emissions testing for this rule, which progresses from daily to weekly to monthly testing, is as follows.

Affected sources would be required to be tested daily for visible emissions with Method 22 for 10 consecutive days that the source is in operation. If visible emissions are not observed during these 10 days, the affected source can be tested once every 5 consecutive days (weekly) that the source is in operation. If no visible emissions are observed during these 4 consecutive weekly Method 22 tests, the affected source can be tested once per consecutive 21 days (month) of operation. If any visible emissions are observed during the weekly and monthly testing, the affected source would resume visible emissions testing in the more frequent schedule, i.e., weekly visible emissions testing is increased to daily, and monthly testing is increased to weekly.

3. Tests for VOHAP Content of Paints in Spray Painting To Determine Continuous Compliance

For owners and operators of new and existing affected spray painting operations, this proposed rule would allow two options for demonstrating compliance with the limitation on the mass of VOHAP contained in their paints: (1) Compliance via paint VOHAP content limit, and (2) compliance via a weighted-average paint VOHAP content limit. Both of these options are pollution prevention strategies.

Since we do not have knowledge of any facilities using other control approaches to control VOHAP emissions, we have not included any other on control options in this proposed rule. We are specifically requesting comments on this part of the proposed rule if our assumptions about the need for an additional compliance option are in error.

Option 1:

Compliance via Paint VOHAP Content Limit

. In this option, the facility determines the VOHAP content of their paints and the volume fraction of paint solids in the paints to compare to the limit of 3.0 pounds VOHAP per gallon paint solids (0.36 kg/liter) on an annual (12-month) rolling average basis.

Facilities may rely on manufacturer's formulation data for determining the VOHAP content of their paints and the volume fraction of paint solids; tests or analysis of the materials would not be required if formulation data are available. Alternatively, results from the following test methods may be used.

For determining the VOHAP content of paints, Method 311 of 40 CFR part 63, appendix A may be used. Nonaqueous volatile matter, excluding water (

i.e.

, VOC) may also be used as a surrogate for VOHAP, since VOC includes all VOHAP as well as any additional organic compounds present in the paint. To determine VOC content of the paints, facilities may use manufacturer's formulation data or Method 24 of 40 CFR part 60, appendix A. For determining the average density of volatile matter in the paint, facilities may use American Society of Testing and Materials (ASTM) Method D1475-98, “Standard Test Method for Density of Liquid Coatings, Inks, and Related Products” (incorporated by reference, see § 63.14 of subpart A of this part). The Director of the Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a copy of these standards from ASTM at

http://www.astm.org

or ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959 U.S.A. You may inspect a copy at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to:

http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html

.

For determining the volume fraction of paint solids, facilities may use: (1) ASTM Method D2697-03, “Standard Test Method for Volume Nonvolatile Matter in Clear or Pigmented Coatings;” or (2) ASTM Method D6093-97 (Reapproved 2003), “Standard Test Method for Percent Volume Nonvolatile Matter in Clear or Pigmented Coatings Using a Helium Gas Pycnometer” (incorporated by reference, see § 63.14 of subpart A of this part). The Director of the Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a copy of these standards from ASTM at

http://www.astm.org

or ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959 U.S.A. You may inspect a copy at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to:

http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html

.

Option 2: Compliance via a Weighted-Average Paint VOHAP Content Limit

. This option would allow a demonstration of compliance based on the VOHAP contained in the mix of paints used. This option offers facilities the flexibility to use some individual paints that do not by themselves meet the paint VOHAP limit, if they also use low-HAP or non-HAP paints such that overall weighted average VOHAP content of all paints used over a 12-month period meets the VOHAP limit. Facilities would likely need to use this option if they use HAP-containing thinners and/or other additives in addition to paints, since these additives usually have high VOHAP contents. Equations are provided in this proposed rule to demonstrate how to perform the calculations to demonstrate compliance.

Facilities would track the mass of VOHAP in each paint and the amount of paint used in affected sources each month of the compliance period. This information would then be used to determine the total mass of VOHAP in all paints along with the total volume of paint solids used during the compliance period by adding together all the monthly values for mass of VOHAP and the monthly values for volume of paint solids used, for the 12 months of the initial compliance period. Facilities may subtract from the total mass of VOHAP the amount contained in waste materials sent to a hazardous waste treatment, storage, and disposal facility regulated under 40 CFR part 262, 264, 265, or 266, “Hazardous Waste.”

Facilities would be required to calculate their overall weighted-average VOHAP paint content (in pound or kilogram VOHAP emitted per gallon or liter paint solids used) and show that this rate meets the VOHAP limit. Facilities may use readily available purchase records and manufacturer formulation data to determine the amount of each paint used and the VOHAP in each material.

In summary, if a facility chooses to demonstrate compliance using Option 2,

Compliance via a Weighted Average

Paint VOHAP Content Limit

, they would be required to determine all the parameters listed below for their paints. Either manufacturer's formulation data or analysis of the materials by approved test methods would be allowable options for determining these values.

• Quantity of each paint, thinner and/or other additive used, from records.

• Mass of VOHAP in each paint, thinner, and other additives, from manufacturer's data or tests.

• Volume fraction of paint solids for each paint, from manufacturer's data or tests.

• Total mass of VOHAP in all materials and total volume of paint solids used each month, by calculation.

• Total mass of VOHAP emissions and total volume of paint solids used for the initial compliance period, by calculation.

• Ratio of the total mass of VOHAP emitted to the total volume of paint solids used for the initial compliance period, by calculation.

With this option, facilities would need to record these calculations and results, and include them in the Notification of Compliance Status. EPA notes that the VOHAP composition of coatings subject to this proposed rule is “emissions data” under section 114 of the CAA, and EPA's regulatory definition of such term in 40 CFR part 2, because the information is necessary to determine compliance with applicable limits. As such, this information must be available to the public regardless of whether EPA obtains the information through a reporting requirement or through a specific request to the regulated entity. Therefore, such information is not eligible for treatment as “confidential business information.”

4. Tests for Spray Painting for MFHAP Control To Determine Continuous Compliance

Affected new and existing facilities that perform spray painting would need to ensure and certify that: (1) All new and existing personnel, including contract personnel, who spray-apply surface paints with MFHAP are trained in the proper application of surface paints; (2) all spray-applied paints with MFHAP are applied with a HVLP spray gun, electrostatic application, airless spray gun, or equivalent; (3) emissions of MFHAP are minimized during mixing, storage, and transfer of paints; and (4) paint and solvent lids are kept tightly closed when not in use.

In addition, for spray painting objects less than 15 feet in any dimension, owners or operators of affected processes would also need to ensure and certify that surface preparation stations or spray booths are fitted with fiberglass or polyester fiber filters or other comparable filter technology that can be demonstrated to achieve at least 98 percent control efficiency of the MFHAP in the paint.

5. Visual Emissions Testing for Welding To Determine Continuous Compliance

For new and existing affected sources with welding operations, this proposed rule would require visible emissions testing from a vent, stack, exit, or opening from the building containing the welding metal fabrication and finishing operations to demonstrate continuous compliance with management practices or add-on controls intended to control PM emissions, as a surrogate for MFHAP. This testing has a three-tier compliance structure.

Tier 1

. The first tier for welding compliance would require visual determinations of fugitive emissions using EPA Method 22, and allows the same graduated testing schedule described above in section (F)(2) for dry abrasive blasting, dry grinding and dry polishing with machines, and machining, which includes provisions for reducing the frequency of the Method 22 tests when no visible emissions are observed in consecutive time periods of operation. If no visible emissions are found, no corrective action would be required.

If visible emissions are present during any Method 22 test, immediate corrective action would be required that includes inspection of all fume sources and control methods in operation, and documentation of the visual emissions test results. The graduated schedule also would require the affected source to resume visible emissions testing in the previous, more frequent schedule, i.e., weekly visible emissions testing is increased to daily, and monthly testing is increased to weekly.

Tier 2

. The second tier for welding compliance would be implemented if visible emissions are detected for the second time in any consecutive twelve-month period. The second tier would require corrective action and documentation of the detection of visible emissions and the corrective action taken. Corrective action would be required to take place immediately after the failed Method 22 test. In addition, the second tier for welding compliance would require a facility to perform a visual determination of emissions opacity using EPA Method 9 (40 CFR part 60, appendix A) within 24 hours of the failed Method 22 test. In EPA Method 9, the average of 24 15-second intervals of opacity observation is determined, producing a total of 360 seconds or 6 minutes of opacity observation or 6-minute average opacity.

If in the second tier tests using Method 9 the average of the 6-minute opacities is determined to be 20 percent or less, implementation of Method 9 testing would be required with a graduated schedule of reduced frequency like that used for the Method 22 tests, described above in section (F)(2), from daily to weekly to monthly for consecutive successful tests. If opacity continues to be less than 20 percent and, pursuant to the graduated schedule the Method 9 testing for the welding processes is able to be reduced to once a month, the facility would have the choice of switching back to performing Method 22 tests on a monthly basis. Alternatively, the facility could choose to continue performing monthly Method 9 tests.

If the average of the 6-minute opacities is determined to be more than 20 percent in the Method 9 tests in the second tier, the third tier of welding compliance requirements would be required, as described below.

Tier 3

. The third tier for welding compliance would include the development and implementation of a Site-specific Welding Emissions Management Plan (SWMP) within 30 days, and submittal of the SWMP to the delegated authority. The SWMP would be required to be kept at the facility in a readily accessed location for inspector review. Also, the facility would be required to report any exceedence of the 20 percent opacity annually along with their annual compliance report.

The purpose of the SWMP is to ensure that no visible emissions occur in the future from this process, as determined by EPA Method 22 tests or less than 20 percent opacity by EPA Method 9. Application of the SWMP may involve implementation of additional management and pollution prevention practices, as described above under Welding Controls, beyond those already in place at the facility or the use of capture equipment and add-on control devices. During the development of the SWMP, daily Method 9 tests would be required to continue to be performed, according to the graduated schedule. The SWMP would be required to be updated after any failures to meet 20 percent or less opacity as determined by Method 9. If opacity continues to be less than 20 percent and Method 9 testing of the welding processes at the facility falls to once a month, according to the graduated testing schedule, the facility would have a choice of changing to monthly Method 22 tests or remaining

with monthly Method 9, as above. The SWMP would be updated annually and would include revisions to reflect any changes in welding operations or controls at the facility.

The SWMP is estimated to require up to 16 hours to prepare initially. We are proposing that the SWMP would address the following: The type(s) of welding operation(s) currently used at the facility; the measures used to minimize welding fume at each of type of welding operation or each welding station; and procedures used by the facility to ensure that these measures are being implemented. No outside consultants or professional engineer certification is required or necessary to prepare the SWMP.

G. What are the notification, recordkeeping, and reporting requirements?

The affected new and existing sources would be required to comply with some requirements of the General Provisions (40 CFR part 63, subpart A), which are identified in Table 3 of this proposed rule. Each facility would be required to submit an Initial Notification and a Notification of Compliance Status according to the requirements in 40 CFR 63.9 in the General Provisions. The affected source would be required to prepare an annual compliance status report and keep this report in a readily available location for inspector review. If there are any exceedences during the year, the facility would submit this annual compliance report with any exceedence reports prepared during the year. The exceedence reports would describe the circumstance of the exceedence and the corrective action taken. We specifically request comment on this proposed requirement for annual compliance report preparation and exceedence report submission.

Facilities also would be required to maintain all records that demonstrate initial and continuous compliance with this proposed rule, including records of all required notifications and reports, with supporting documentation; records showing compliance with management and pollution prevention practices. Owners and operators would also maintain records of the following, if applicable: Date and results of all visual determinations of fugitive emissions, including any follow-up tests and corrective actions taken; date and results of all visual determinations of emissions opacity, and corrective actions taken; and a copy of the SWMP, if it is required.

IV. Rationale for This Proposed Rule

A. How did we select the source category?

The nine metal fabrication and finishing source categories were listed as area source categories on November 22, 2002 (67 FR 70427). The inclusion of these source categories on the area source category list was based on data from the CAA section 112(k) inventory, which represents 1990 urban air information. Those data indicated that metal fabrication and finishing plants were contributors to MFHAP emissions in urban areas.

For these source categories, we performed site visits and written facility surveys, reviewed published literature, reviewed information from Web sites of vendors of air pollution control devices, and held discussions with trade organizations and industry experts. From this research we found that the nine source categories perform the same HAP-emitting processes, and, if the process was present, the emissions were controlled in the same way. Consequently, we decided to issue regulations for these nine metal fabrication and finishing area source categories in one rulemaking action.

B. How did we select the affected sources?

We found in on our research described above in section IV(A) that potential sources of HAP emissions from the nine metal fabrication and finishing source categories include the following five general metal fabrication and finishing operations: (1) Dry abrasive blasting; (2) machining; (3) dry grinding and dry polishing with machines; (4) spray painting; and (5) welding. We found that MFHAP are used in and have the potential to be emitted from these operations. Therefore, we selected the facilities with these processes in the source categories as the affected sources for this proposed rule. Because the MFHAP may be emitted as fugitives, we have elected to define the affected sources as the collection of all equipment and activities necessary to perform dry abrasive blasting, machining, dry grinding and dry polishing with machines, spray painting, and welding.

Four of the metal fabrication and finishing source categories were also listed for emissions of the organic HAP TCE.

4

Chlorinated solvents such as TCE are used as degreasers in these metal fabrication and finishing source categories. We subsequently discovered that the 1990 emissions data for TCE was for metal fabrication and finishing facilities that used TCE in degreasing operations, which are not part of this source category. Rather, these emission units at both major and area sources are subject to standards for halogenated solvent cleaning under 40 CFR part 63, subpart T. Consequently, we are not proposing standards for TCE from metal fabrication and finishing facilities. The four metal fabrication and finishing source categories listed for TCE emissions remain listed source categories pursuant to section 112(c)(3) of this part, and this proposed rule establishes standards for emissions of MFHAP and VOHAP. Therefore, we are clarifying that we do not need these four source categories to meet the section 112(c)(3) 90 percent requirement regarding area source emissions of TCE.

4

These four source categories were Electrical and Electronic Equipment Finishing Operations; Fabricated Metal Products; Primary Metal Products Manufacturing; and Valves and Pipe Fittings.

We also found that some metal fabrication and finishing facilities also perform plating. All chromium electroplating tanks are already subject to the Chromium Electroplating NESHAP (40 CFR part 63, subpart N), while other plating operations at area sources are subject to the Plating and Polishing Area Source Rule (40 CFR part 63, subpart WWWWWW). Therefore, these sources would not be affected sources under this proposed rule for metal fabrication and finishing area sources.

C. How did we determine the regulated processes?

We found in our research for this proposed rule that there are five general production operations common to the nine metal fabrication and finishing source categories that can emit MFHAP: (1) Dry abrasive blasting; (2) dry grinding and dry polishing with machines; (3) machining; (4) spray painting; and (5) welding. As part of our analyses, we considered whether there were differences in the operations, the products fabricated or finished, or other factors affecting emissions that would warrant different control strategies. Under section 112(d)(1) of the CAA, EPA “may distinguish among classes, types, and sizes within a source category or subcategory in establishing such standards * * *”

We observed significant differences in processes for two of the five metal fabrication and finishing operations: Dry abrasive blasting and painting. Considering these differences in the processes, we identified nine distinct metal fabrication and finishing processes for the purposes of this proposed rule. A discussion of how we

identified these nine processes follows below.

1. Dry Abrasive Blasting Regulated Processes

Some dry abrasive blasting operations for small parts with low-throughput are performed in completely enclosed units commonly called “glove boxes,” which have no air outlet or ventilation and, hence, no emissions when designed and operated properly. These sources are distinctly different from larger operations which are not completely enclosed because of the limitations of their size.

Most dry abrasive blasting of larger objects and/or large throughput operations performed at metal fabrication and finishing area sources is performed in enclosed spaces, which are typically equipped with cartridge filters or other control devices on the air exhaust. However, it is not always practical to completely enclose dry abrasive blasting of very large objects (

e.g.

, oil derricks) because of the size and subsequent cost of the enclosure and also difficulty maneuvering the object into the enclosure. The impracticality of this effort is particularly evident when the operation is only performed intermittently. Consequently, dry abrasive blasting of very large objects is sometimes performed outdoors or in 2- or 3-sided buildings that are open on one or more sides to allow the large articles to be easily moved into the blasting zone by heavy equipment or cranes.

We found State regulations that allow outdoor dry abrasive blasting operations for objects over 8 feet in any one dimension. We also found through our industry surveys that these very large objects were blasted outdoors. We also learned that facilities are motivated to enclose dry abrasive blasting operations whenever possible because of the potential cost savings from recovering the blast material which lowers blast material usage and also costs, so that outside blasting is only performed when necessary because of the size of the parts or products.

Consequently, we determined for the purposes of this proposed rule that there were two distinct sizes of products being blasted that affected the manner in which the process was performed: Products more than 8 feet in any dimension, and products less than or equal to 8 feet. For products less than or equal to 8 feet, we also observed that some of these products were blasted in completely enclosed chambers that did not allow any air or emissions to escape. Therefore, we developed three distinct dry abrasive blasting processes: (1) Dry abrasive blasting of objects greater than 8 feet in any dimension; (2) dry abrasive blasting of objects less than or equal to 8 feet in any dimension, performed in completely enclosed and unvented blast chambers; and (3) dry abrasive blasting of objects less than or equal to 8 feet in any dimension, performed in vented enclosures.

2. Spray Painting Regulated Processes

Most spray painting performed at metal fabrication and finishing area sources is performed in enclosed spray paint booths, which are typically equipped with filters for PM control, where PM is a surrogate for MFHAP. Because of the impracticality of enclosing large objects in booths, similar to the discussion above for dry abrasive blasting, we found that it is common practice in the industry for these sources to spray paint large objects outside or in 2- or 3-sided buildings. We found that the size of objects typically spray painted outside are approximately 15 feet in any one dimension.

Therefore, we determined that there were two distinct sizes of products being painted that affected the manner in which the process was performed: (1) Products more than 15 feet in any dimension; and (2) products equal to or less than 15 feet in any dimension. Therefore, we developed two distinct spray painting processes for MFHAP control: (1) Spray painting of objects less than or equal to 15 feet in any dimension; and (2) spray painting of objects greater than 15 feet in any dimension.

It should be noted that the object size cut-off for the spray painting processes is more stringent than the one selected for dry abrasive blasting in that objects between 8 and 15 feet in dimension are enclosed for spray painting but not for blasting. This difference occurs because the MFHAP overspray from uncontrolled spray painting is higher, more hazardous, and more of a nuisance (

i.e.

, more odor, clean-up, etc.) than the inert PM and low level of MFHAP emitted from dry abrasive blasting. Therefore, painting spray booths need to be sealed better, whereas in dry abrasive blasting the structures can be partially enclosed.

We also determined that there was the potential for significant VOHAP emissions from painting that are not controlled by the PM capture and control equipment described above. We also observed that for the purposes of controlling VOHAP, it was not necessary to distinguish between sizes of the objects painted. Therefore, we are proposing one standard for control of VOHAP emissions from spray painting that would apply to all spray painting operations. Since this standard is a pollution prevention technique that restricts the types of coatings used in spray painting, it does not differentiate the size of the product being painted.

3. Other Regulated Processes

For dry grinding and dry polishing with machines; machining; and welding we did not observe any distinct differences that would warrant differentiating the operations into separate processes. Therefore, these three operations are included as individual regulated processes in this proposed rule.

4. The Nine Regulated Processes in the Metal Fabrication and Finishing Source Categories

In the above section IV(C)(1), we discussed how we divided dry abrasive blasting operations into three processes for the purposes of this proposed rule. In the above section IV(C)(2), we discussed how we divided painting operations into three processes for regulation. The remaining three operations were not further divided, as discussed above in section (C)(3). The result of these analyses is that we have identified the following nine metal fabrication and finishing processes for this proposed rule:

(1) Dry abrasive blasting objects less than or equal to 8 feet in any dimension, performed in completely enclosed and unvented blast chambers;

(2) Dry abrasive blasting of objects less than or equal to 8 feet in any dimension, performed in vented enclosures;

(3) Dry abrasive blasting of objects greater than 8 feet in any dimension;

(4) Dry grinding and dry polishing with machines;

(5) Machining;

(6) Control of VOHAP from spray painting;

(7) Control of MFHAP in spray painting of objects less than or equal to 15 feet in any dimension;

(8) Control of MFHAP in spray painting of objects greater than 15 feet in any dimension; and

(9) Welding.

D. How was GACT determined?

We are proposing nine standards representing GACT for the metal fabrication and finishing source categories, as provided in CAA section 112(d)(5). The information used to determine the proposed GACT is derived from site visits and written facility surveys, published literature, information from websites of vendors of air pollution control devices, and

discussions with trade organizations and industry experts. We found that the MFHAP emissions from the nine metal fabrication and finishing source categories are already well controlled by the industry, where MFHAP is controlled as PM, a surrogate for MFHAP. The facilities were motivated to control these MFHAP emissions to improve health and safety of the worker's environment and to save raw material use.

We evaluated the control technologies and management practices that are current industry practice for the nine metal fabrication and finishing area source categories. See Section II(C)(3) above, “Metal Fabrication and Finishing HAP Emission Controls,” for a discussion of the controls used in the metal fabrication and finishing source categories. We also evaluated the control technologies used in similar industries. We did not identify any major sources of MFHAP in these nine source categories.

We also considered costs and economic impacts in determining GACT. We believe the consideration of costs and economic impacts is especially important for metal fabrication and finishing sources because requiring additional controls would result in only marginal reductions in emissions at very high costs for a modest incremental improvement in MFHAP control, and because more than 90 percent of metal fabrication and finishing facilities are small businesses.

Since we have concluded that the industry was already well-controlled, we have developed GACT requirements to insure that these gains in emission control from the 1990 levels are continued. We explain below in detail our proposed GACT determinations.

1. GACT for Dry Abrasive Blasting

Dry abrasive blasting generates much PM and to a lesser degree MFHAP from substrate material, and any dirt and paint if the substrate was previously used. We found that it is standard industry practice to control indoor blasting by either a total enclosure with no exhaust or a total enclosure exhausted to PM filtration devices where PM is controlled as a surrogate for MFHAP. Facilities in the industry have enclosed these processes due to the significant cost savings that results from the ability to recycle the used blast material.

We also found that it is standard industry practice to perform blasting of large objects outdoors since they cannot fit easily inside enclosures. Many State laws allow dry abrasive blasting outdoors for objects over 8 feet in any one dimension. Therefore, we concluded that this is a separate process different from the indoor blasting which was described above.

Consequently, we developed three distinct processes for dry abrasive blasting operations the purposes of this proposed rule, as follows: (1) Dry abrasive blasting objects less than or equal to 8 feet in any dimension, performed in completely enclosed and unvented blast chambers; (2) dry abrasive blasting of objects less than or equal to 8 feet in any dimension, performed in vented enclosures; and (3) dry abrasive blasting of objects greater than 8 feet in any dimension. The following is a discussion of how we developed GACT for these three processes.

a.

Dry Abrasive Blasting Objects Less Than or Equal to 8 Feet in Any Dimension, Performed in Completely Enclosed and Unvented Chambers.

We found that it is standard industry practice to use total enclosures with no exhaust for some dry abrasive blasting operations of objects less than or equal to 8 feet. Therefore, we are proposing that GACT for this dry abrasive blasting process is management practices because controls in the form of total enclosures are already a part of the process equipment and do not allow PM, as a surrogate for MFHAP, to be emitted during blasting. These two management practices are as follows: (1) Minimize dust generation during emptying of the enclosure; and (2) operate all equipment used in the blasting operation according to manufacturer's instructions. These management practices are standard industry practice for “good housekeeping” in and around dusty processes, and are applicable when the chambers are opened for cleaning after blasting is competed.

b.

Dry Abrasive Blasting of Objects Less than or Equal to 8 Feet in any Dimension, Performed in Vented Enclosures.

We found that it is standard industry practice to control some indoor blasting operations of objects less than or equal to 8 feet by using an enclosure exhausted to PM filtration devices, where PM is controlled as a surrogate for MFHAP. Since these dry abrasive blasting operations are enclosed, capturing and filtering the exhaust enables recycling of the blast material, which is a cost savings to the facility and standard industry practice. We learned from the facilities in the industry that the indoor workplace would not be tolerable without the blasting controls that we are proposing as GACT. Therefore, we propose that GACT for this process is an equipment standard of enclosures and filtration that captures and collects the PM emitted, as a surrogate for MFHAP. We are also proposing management practices as GACT that are standard industry practice or “good housekeeping” for in and around dusty processes, as follows: (1) Keep work areas free of excess dust by regular sweeping or vacuuming to control the accumulation of dust and other particles; regular sweeping or vacuuming is defined to be sweeping or vacuuming conducted once per day, once per shift, or once per operation as needed, depending on the severity of dust generation; (2) enclose dusty material storage areas and holding bins, seal chutes and conveyors; and (3) operate all equipment according to manufacturer's instructions.

c.

Dry Abrasive Blasting of Objects Greater Than 8 Feet in any Dimension.

We found that it is standard industry practice to perform outdoor blasting of large objects that cannot fit easily inside an enclosure. We also found that many State laws allow dry abrasive blasting outdoors if performed on objects larger than 8 feet in any one dimension. It is not standard practice in metal fabrication and finishing facilities to enclose these processes and would be a significant cost to the facility to do so because of the large size of the objects, at approximately $110 million per ton of MFHAP removed.

Because of the burden an enclosure requirement would entail for facilities that perform abrasive blasting of large objects, we propose the GACT requirement for objects greater than 8 feet in any dimension, where the blasting is performed outdoors, to be management practices that minimize MFHAP emissions, as follows: (1) Do not perform blasting outside when wind velocity is greater than 25 mph; (2) switch from high PM-emitting blast media (e.g., sand) to low PM-emitting blast media (e.g., steel shot, aluminum oxide), whenever practicable; (3) do not blast substrates having coatings containing lead (>0.1 percent lead), unless enclosures, barriers, or other PM control methods are used to collect the lead particles; (4) do not re-use the blast media unless contaminants (i.e., any material other than the base metal, such as paint residue) have been removed by filtration or screening so that the dry abrasive material conforms to its original size and makeup; (5) keep work areas free of excess dust by regular sweeping or vacuuming to control the accumulation of dust and other particles; regular sweeping or vacuuming is defined to be sweeping or

vacuuming conducted once per day, once per shift, or once per operation as needed, depending on the severity of dust generation; (6) enclose dusty material storage areas and holding bins, seal chutes and conveyors; and (7) operate all equipment according to manufacturer's instructions.

2. GACT for Dry Grinding and Dry Polishing With Machines

We found that it is standard industry practice to capture PM emissions, as a surrogate for MFHAP, from dry grinding and dry polishing with machines, by the use of local exhaust, hoods, or other vacuum devices; and to collect the PM with filtration devices, such as cartridge filters. Facilities have reported that the indoor workplace would not be tolerable without these types of controls on dry grinding and dry polishing with machines.

Therefore, we propose that GACT for dry grinding and dry polishing with machines would be the equipment standard of capture and control with filtration devices. We also propose management practices that are standard industry procedures and common “good housekeeping” practices in and around dusty processes, as follows: (1) Keep work areas free of excess dust by regular sweeping or vacuuming to control the accumulation of dust and other particles; regular sweeping or vacuuming is defined to be sweeping or vacuuming conducted once per day, once per shift, or once per operation as needed, depending on the severity of dust generation; and (2) operate all equipment used in dry grinding and dry polishing with machines according to manufacturer's instructions.

3. GACT for Machining

The majority of the PM released by machining processes consists of large particles or metal shavings that fall immediately to the floor. Any MFHAP that is released would originate from the part or product being machined. We found that it is general industry practice to totally enclose the machining process and/or use lubricants or liquid coolants that do not allow small particles to escape. Therefore, we are proposing that GACT for machining is the following two management and pollution prevention practices: (1) Keep work areas free of excess dust by regular sweeping or vacuuming to control the accumulation of dust and other particles; regular sweeping or vacuuming is defined to be sweeping or vacuuming conducted once per day, once per shift, or once per operation as needed, depending on the severity of dust generation; and (2) operate all equipment used in machining operations according to manufacturer's instructions.

4. GACT for Spray Painting To Control MFHAP

Emissions from spray painting include MFHAP from the paint pigments. Spray painting performed indoors at metal fabrication and finishing area sources is required by OSHA regulations to be performed in an enclosed spray paint booth. We found that these booths are typically equipped with filters for PM control, where PM is a surrogate for MFHAP. Because of the impracticality of enclosing very large objects in booths, we also found that it is common practice in the industry to spray paint large objects outside or in 2- or 3-sided structures. We found that the size of objects typically spray painted outside are approximately 15 feet in any one dimension. Therefore, we determined that there were two distinct sizes of products being painted that affected the manner in which the process was performed: (1) Products greater than 15 feet in any dimension, and (2) products less than or equal to 15 feet in any dimension. Accordingly, we developed GACT requirements for each of these two processes. The following describes our proposed GACT and the rationale for selecting the GACT requirements for these two processes.

a. GACT Requirements for Control of MFHAP in Spray Painting Objects Greater Than 15 Feet in Any Dimension

The GACT requirements in this proposed rule would require owners or operators of affected new and existing spray painting operations to comply with one equipment standard: (1) Use of low-emitting and pollution preventing spray gun technology. The proposed rule also would require two management practices: (1) Spray painter training; and (2) spray gun cleaning.

Spray Gun Technology Requirements—We are proposing that GACT for this proposed rule would require all affected new and existing facilities using spray-applied paints to use HVLP spray guns, electrostatic application, or airless spray techniques. Alternatively, an equivalent technology can be used if it is demonstrated to achieve transfer efficiency comparable to one of the spray gun technologies listed above for a comparable operation, and for which written approval has been obtained from the Administrator or delegated authority.

Spray Painting Training Requirements—We are proposing that GACT for this proposed rule would require all workers that perform spray painting at affected new and existing facilities to be trained, with certification made available that this training has occurred. For the purposes of the proposed training requirements, the facility owner or operator may certify that their employees have completed training during “in-house” training programs. Also, facilities that can show by documentation or certification that a painter's work experience and/or training has resulted in training equivalent to the training described above would not be required to provide the initial training required for these painters. The training would need to address the following topics to reduce paint overspray, which has a direct effect on emissions reductions: Spray gun equipment selection, set up, and operation; spray technique for different types of paints to improve transfer efficiency and minimize paint usage and overspray; and routine spray booth and filter maintenance, including filter selection and installation. Spray painters have 180 days to complete training after hiring or transferring into a surface painting job from another job in the facility. The training and certification for this proposed rule would be valid for a period not to exceed 5 years after the date the training is completed.

Spray Gun Cleaning Requirements—We are proposing that GACT for this proposed rule would require all paint spray gun cleaning operations at affected new and existing facilities to use an atomized mist or spray such that the gun cleaning solvent and paint residue is not created outside of the container that collects the used gun cleaning solvent. These gun cleaning methods include hand cleaning of parts, use of a fully enclosed spray gun washer, or a combination of these non-atomizing methods. Hand cleaning is considered equivalent to gun washers as long as the painters do not atomize cleaning solvent from the gun and the spent solvent is collected in a container that is closed when not in use.

b. Rationale for GACT To Control MFHAP in Spray Painting Objects Greater Than 15 Feet in Any Dimension

Some facilities paint large objects (greater than 15 feet) in open air or 2-sided buildings so that the objects can be moved in and out with cranes and other heavy equipment. It is not standard practice in metal fabrication and finishing facilities to enclose these operations in booths and would be a significant cost to the facility to do so because of the large size of the objects, at approximately $20 million per ton of MFHAP removed for large spray booths.

However, in order to minimize paint waste and exposure of the worker to paint overspray, it is standard industry practice for facilities that spray paint large objects to use HVLP equivalent high transfer efficiency spray techniques even though they are not enclosing the paint operation and filtering the exhaust air.

These HVLP spray painting technologies produce a 40 percent decrease in paint consumption and resultant emissions compared to conventional spray guns. Conventional high-pressure air-atomized spray guns have a typical transfer efficiency of about 30 percent while HVLP and other types of high-efficiency spraying use lower air pressures and achieve a transfer efficiency of about 50 percent, or greater, with appropriate operator training. The HVLP spray method we are proposing as GACT is a pollution prevention technology that is standard industry practice and reduces the amount of paint sprayed. The HVLP spray method reduces paint costs to the facility, reduces worker exposure to paint overspray, reduces clean-up requirements, and also reduces MFHAP emissions.

Because of the burden an enclosure requirement would entail for facilities that paint large objects, we propose the equipment standard for GACT for these sources to be a requirement for HVLP spray gun use. We chose the size requirement for indoor spray painting at 15 feet based on industry information. We specifically request comment on our size cut-off on affected sources of this requirement. In addition, we are proposing management practices as GACT to ensure that workers are trained properly in the high efficiency spray painting techniques and that the spry equipment is washed in a way that minimizes atomization of the paint, which can cause MFHAP emissions to occur. The HVLP training and equipment cleaning procedures are common practice in this industry as well as other similar industries. To minimize the impact on small business, the facility owner or operator may perform this training during “in-house” training programs. Also, facilities can show that a painter's work experience and/or training have resulted in equivalent training and, therefore, would not be required to provide training at an external location for these painters.

This proposed rule would require all paint spray gun cleaning operations at affected new and existing facilities to be performed such that the gun cleaning solvent and paint residue is not created outside of the container that collects the used gun cleaning solvent. These gun cleaning methods include hand cleaning of parts, use of a fully enclosed spray gun washer, or a combination of these non-atomizing methods. Hand cleaning is considered equivalent to gun washers as long as the painters do not atomize cleaning solvent from the gun and the spent solvent is collected in a container that is closed when not in use. Since facilities that do not currently have an automated gun washer can still comply with the proposed standards by cleaning guns by hand, we do not expect that sources would have any annualized capital costs or operating costs for spray gun cleaning.

c. GACT Requirements for Control of MFHAP in Spray Painting Objects Equal To or Less Than 15 Feet in Any Dimension

This proposed rule would require affected new and existing facilities that are spray painting objects less than or equal to 15 feet in any dimension to comply with two equipment standards: (1) Use of low-emitting and pollution preventing spray gun technology, and (2) use of spray booth PM filters. This proposed rule also would require two management practices: (1) Spray painter training, and (2) spray gun cleaning.

Spray Booth PM Control Requirement—We are proposing that GACT for this proposed rule would require the surface preparation stations or spray booths of affected new and existing facilities to be fitted with fiberglass or polyester fiber filters or other comparable filter technology that can be demonstrated to achieve at least 98 percent control efficiency of paint overspray (also referred to as “arrestance”). As an alternative compliance option, spray booths may be equipped with a water curtain that achieves at least 98 percent control of MFHAP. The waterspray booths would be required to be operated and maintained according to the manufacturer's specifications.

Spray Gun Technology Requirements—We are proposing that GACT for this proposed rule would require all affected new and existing facilities using spray-applied paints to use HVLP spray guns, electrostatic application, or airless spray techniques. Alternatively, an equivalent technology can be used if it is demonstrated to achieve transfer efficiency comparable to one of the spray gun technologies listed above for a comparable operation, and for which written approval has been obtained from the Administrator or delegated authority.

Spray Painting Training Requirements—We are proposing that GACT for this proposed rule would require all workers that perform spray painting at affected new and existing facilities to be trained, with certification made available that this training has occurred. The training would need to address the following topics to reduce paint overspray, which has a direct effect on emissions reductions: Spray gun equipment selection, set up, and operation; spray technique for different types of paints to improve transfer efficiency and minimize paint usage and overspray; and routine spray booth and filter maintenance, including filter selection and installation. Spray painters have 180 days to complete training after hiring or transferring into a surface painting job from another job in the facility. For the purposes of the proposed training requirements, the facility owner or operator may certify that their employees have completed training during “in-house” training programs. Also, facilities that can show by documentation or certification that a painter's work experience and/or training has resulted in training equivalent to the training described above would not be required to provide the initial training required for their painters. The training and certification for this proposed rule would be valid for a period not to exceed 5 years after the date the training is completed.

Spray Gun Cleaning Requirements—We are proposing that GACT for this proposed rule would require all paint spray gun cleaning operations at affected new and existing facilities to use an atomized mist or spray such that the gun cleaning solvent and paint residue is not created outside of the container that collects the used gun cleaning solvent. These gun cleaning methods include hand cleaning of parts, use of a fully enclosed spray gun washer, or a combination of these non-atomizing methods. Hand cleaning is considered equivalent to gun washers as long as the painters do not atomize cleaning solvent from the gun and the spent solvent is collected in a container that is closed when not in use.

d. Rationale for GACT To Control MFHAP in Spray Painting Objects Equal To or Less Than 15 Feet in Any Dimension

We are proposing that GACT for this process includes management practices and equipment standards. Our proposed GACT for this process includes the use of the pollution prevention spray painting technologies such as HVLP spray guns or their equivalent. These spray painting technologies produce a 40 percent decrease in paint consumption and resultant emissions

compared to conventional spray guns. Conventional high-pressure air-atomized spray guns have a typical transfer efficiency of about 30 percent while HVLP and other types of high-efficiency spraying use lower air pressures and achieve a transfer efficiency of about 50 percent, or greater, with appropriate operator training.

The HVLP spray method we are proposing as GACT is a pollution prevention technology that is standard industry practice in this industry as well as other similar industries, and reduces the amount of paint sprayed. The HVLP spray method reduces paint costs to the facility, reduces worker exposure to paint overspray, reduces clean-up requirements, and also reduces MFHAP emissions.

In addition, we are proposing management practices as GACT to ensure that workers are trained properly in the high efficiency spray painting techniques and that the spray equipment is washed in a way that minimizes atomization of the paint, which can cause MFHAP emissions to occur. The HVLP training and equipment cleaning procedures are common practice in this industry as well as other similar industries. To minimize the impact on small business, the facility owner or operator may perform this training during “in-house” training programs. Also, facilities can show that a painter's work experience and/or training have resulted in equivalent training and, therefore, would not be required to provide training at an external location for their painters.

We also propose that GACT for spray painting objects less than or equal to 15 feet is the use of a spray booth equipped with a high efficiency PM filter that removes MFHAP. OSHA already requires that all indoor spray painting be performed in an enclosed booth or room, with the exhaust vented through a filter. Therefore, upgrade of a spray booth to include a PM filter to control MFHAP is only a small change to the current process. The PM filters that

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