MEMORANDUM

TO: Kim Teal, U.S. EPA/OAQPS

FROM: Eastern Research Group, Inc.

DATE: October 29, 2015

SUBJECT: Technology Review for Waste Storage and Handling Operati ons in the Aerospace

Manufacturing and Rework Source Category

1.0 

### INTRODUCTION

Section 112 of the Clean Air Act (CAA) requires the U.S . Environmental Protection Agency (EPA) to establish technology-based standards for listed source categories. These technology-based standards are often referred to as maxim um achievable control technology (MACT) standards. The Aerospace MACT (40 CFR part 63, subpart GG) regulates HAP emissions from facilities that are major sources and a re engaged, either in part or in whole, in the manufacture or rework of commercial, civil, or milita ry aerospace vehicles or components. The rule requires the use of MACT to reduce HAP emissions f rom the following operations: cleaning; primer, topcoat and chemical milling maskant applic ation; depainting; and waste storage and handling.

Section 112 also contains provisions requiring the EPA to peri odically revisit these standards. Specifically, section 112(d)(6) states:

(6) REVIEW AND REVISION. – The Administrator shall r eview, and revise as necessary (taking into account developments in practices , processes, and control technologies), emissions standards promulgated under this se ction no less often than every 8 years.

To comply with this CAA requirement, the EPA conducted a technology review for the Aerospace MACT standard for major sources. This memoran dum addresses the portion of the technology review for waste storage and handling from the aerospace manufacturing and rework surface coating operations.

For the purposes of reviewing a MACT standard, the EPA con siders a “development” in practices, processes, and control technologies to be:

• Any add-on control technology or other equipment that was not identified and considered during MACT development; www.erg.com• Any improvements in add-on control technology or other e quipment (that was identified

and considered during MACT development) that could result in significant additional emission reduction;

• Any work practice or operational procedure that was not i dentified and considered during MACT development; and

• Any process change or pollution prevention alternative t hat could be broadly applied that was not identified and considered during MACT development.

• Any significant changes in the cost (including cost effe ctiveness) of applying controls (including controls the EPA considered during the developme nt of the original MACT standards).

Section 2 of this memorandum presents a summary of the sources of data that were used to conduct the technology review, and Section 3 presents t he technology review for waste storage and handling.

2.0 

### SOURCES OF AVAILABLE CONTROL TECHNOLOGY INFORMATION

To identify any developments in practices, processes, or c ontrol technologies that could be applicable to waste storage and handling operations in t he Aerospace industry, we consulted the following sources of data: RACT/BACT/LAER Clearingho use, the California Statewide Best Available Control Technology (BACT) Clearinghouse, regulat ory actions promulgated subsequent to the Aerospace MACT, and regional and state re gulations.

The EPA did not find any information specific to waste stor age and handling for surface coating operations in the California BACT Clearinghouse.

In addition, the EPA sent out a comprehensive informatio n collection request (ICR) to all known aerospace manufacturing and rework facilities in Fe bruary 2011. The ICR requested information on material usage and control techniques used on all of the regulated and unregulated emission sources. The 2011 ICR did not request informa tion specific to waste storage and handling operations, although it did request infor mation on cleaning operations and on storage tanks associated with regulated operations. How ever, the information was not sufficiently detailed to identify waste storage and handli ng operations that were not part of the cleaning operations, or that were part of the surface coa ting operations and not subject to another

NESHAP.

2.1 RACT/BACT/LAER Clearinghouse Database

Under the EPA's New Source Review (NSR) program, if a co mpany is planning to build a new plant or modify an existing plant such that crit eria air pollution emissions will increase by a certain amount, then the company must obtain an NSR pe rmit. The NSR permit is a construction permit which generally requires the company to minimize air pollution emissions by changing the process to prevent air pollution and/or instal ling air pollution control equipment.

The terms "RACT," "BACT," and "LAER" are acronyms for different program requirements relevant to the NSR program. RACT, or Reaso nably Available Control Technology, is required on sources in areas that are no t meeting national ambient air qualitystandards (non-attainment areas). BACT, or Best Availabl e Control Technology, is required on

new or modified major sources in clean areas (attainme nt areas). LAER, or Lowest Achievable Emission Rate, is required on new or modified major sou rces in non-attainment areas.

BACT and LAER (and sometimes RACT) are determined on a c ase-by-case basis, usually by state or local permitting agencies. The EPA esta blished the RACT/BACT/LAER Clearinghouse, or RBLC, to provide a central data base of air pollution technology information (including past BACT and LAER decisions contained in NSR pe rmits) to promote the sharing of information among permitting agencies and to aid in future case-by-case determinations. However, data in the RBLC are not limited to sources subj ect to RACT, BACT, and LAER requirements. Noteworthy prevention and control technolog y decisions and information may be included even if they are not related to past RACT, BACT, or LAER decisions.1

The RBLC contains over 5,000 air pollution control permit de terminations that can help identify appropriate technologies to mitigate most air po llutant emission streams. It was designed to help permit applicants and reviewers make pollution preve ntion and control technology decisions for stationary air pollution sources, and incl udes data submitted by several U.S. territories and all 50 States on over 200 different air po llutants and 1,000 industrial processes.

The RBLC provides several options for searching the permit database on-line to locate applicable control technologies. On September 26 and 27 and October 25, 2013, we conducted a search of the RBLC. There is no process category in th e RBLC that closely matches waste storage and handling. Our search specified processes in th e Waste Disposal category, Other Waste Processing and Disposal subcategory, with permits dating back to September 1, 1995, which is the promulgation date of the Aerospace MACT. T he searches of these process categories returned no determinations for processes that were at all similar to the waste storage and handling affected source at aerospace facilities.

We also searched the RBLC for the Aerospace Surface Co ating process category and other similar surface coating processes (Automobiles and T rucks Surface Coating (OEM), Large Appliance Surface Coating, Miscellaneous Metal Parts and Products Surface Coating, and Plastic Parts and Products Surface Coating) and other process catego ries that would be expected to generate waste solvents (Organic Solvent Cleaning and Degre asing, Halogenated Solvent Cleaning). We found no entries related to the waste stora ge and handling affected facility as defined in the aerospace standard. Finally, we searched th e RBLC across all process categories for any that contain the word “waste.” While there are many such entries, none were related to the waste storage and handling affected source; most wer e related to wastewater, waste heat boilers, and solid waste.

2.2 Subsequent Regulatory Actions

We reviewed technology reviews conducted by EPA for other so urce categories; however, none of these technology reviews addressed oper ations that are similar to the Aerospace MACT waste storage and handling affected source.

1 Technology Transfer Network: Clean Air Technology Cent er. RACT/BACT/LAER Clearinghouse Basic Information. http://www.epa.gov/ttn/catc/rblc/htm/welcome_eg.html

.In addition, we reviewed the requirements of MACT standa rds promulgated subsequent

to the Aerospace MACT (September 1, 1995) for source categor ies that might be expected to generate liquid HAP-containing wastes, such as surface coa ting, chemical manufacturing, printing, and solvent cleaning. We reviewed the following MACT standards (with year of promulgation):

• Subpart U— National Emission Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins (1996)

• Subpart DD—National Emission Standards for Hazardous Air P ollutants from Off-Site Waste and Recovery Operations (1996)

• Subpart II—National Emission Standards for Shipbuilding and S hip Repair (Surface Coating) (1995, 3 months after the Aerospace MACT)

• Subpart JJ—National Emission Standards for Wood Furniture Man ufacturing Operations (1995, 3 months after the Aerospace MACT)

• Subpart KK—National Emission Standards for the Printing a nd Publishing Industry (1996)

• Subpart GGG—National Emission Standards for Pharmaceutical s Production (1998)

• Subpart IIII—National Emission Standards for Hazardous Air Pollutants: Surface Coating of Automobiles and Light-Duty Trucks (2004)

• Subpart MMMM—National Emission Standards for Hazardous Ai r Pollutants for Surface Coating of Miscellaneous Metal Parts and Products (2004)

• Subpart NNNN—National Emission Standards for Hazardous Air Pollutants: Surface Coating of Large Appliances (2002)

• Subpart PPPP—National Emission Standards for Hazardous Air Pollutants for Surface Coating of Plastic Parts and Products (2004)

Some of these standards address only wastewater (subpart s U, KK, and GGG), and others include waste coating and solvents in provisions that addres s a larger universe of materials and equipment (subparts II and JJ).

While subpart DD, the Off-Site Waste MACT, specificall y addresses the handling and storage of wastes, it was found not to be particularly relevant because the regulated emissions points are generally of a type and scale unlike the affec ted source in the Aerospace MACT. For example, subpart DD regulates oil-water separators and s urface impoundments. A possible exception occurs at the smaller end of the “container” category – covers are required on containers as small as 0.1 cubic meter (m3) or about 26 gallon s. However, covers do not represent improved control over the current Aerospace MA CT, as discussed below in section 3.

The standards that address handling and storage of liquid HAP -containing wastes all employ work practice controls similar to the Aerospac e MACT. A number include the additionalrequirement to develop and implement a work practice plan to minimize organic HAP emissions from the storage, mixing, and conveying of materials that con tain such HAP.

2.3 State and Regional Regulations

In addition to the RLBC and subsequent regulatory actions , we examined a variety of regulations of the Bay Area Air Quality Management Di strict (BAAQMD), the South Coast Air Quality Management District (SCAQMD), the Delaware De partment of Natural Resources and Environmental Control, the Maricopa County (Arizona) Air Quality Department, and the Ozone Transport Commission (Northeast United States). These included regulations for the aerospace source category; other surface coating operations; coati ng and ink manufacturing; and other processes using solvents, such as solvent cleaning operation s, dry cleaning, and degreasing. These regulations generally address VOC emissions, rathe r than volatile organic HAP emissions, but in many cases include provisions to reduce evaporative em issions of solvent just as intended for the waste storage and handling affected source under t he Aerospace MACT.

Based on the review of these regulations, those that addr ess disposal of VOC-containing wastes all employ work practice controls similar to th e Aerospace MACT. The review did not identify any requirements in these rules that are clea rly more stringent than the requirements for this affected source under the Aerospace MACT.

3.0 TECHNOLOGY REVIEW FOR WASTE STORAGE AND HANDLING

On September 1, 1995, the EPA finalized subpart GG for exist ing and new major sources in the aerospace manufacturing and rework facilities so urce category. The requirements for waste storage and handling promulgated in Subpart GG apply to e ach waste storage and handling operation, which is the total of all waste handling and s torage at the facility. Per §63.741(e) in subpart GG as promulgated in 1995, all wastes that are deter mined to be hazardous wastes under the Resource Conservation and Recovery Act of 1976 (PL 94-580 ) (RCRA) as implemented by 40 CFR parts 260 and 261, and that are subject to RCRA requirement s as implemented in 40 CFR parts 262 through 268, are exempt from the requirements of subpart GG.

At aerospace manufacturing and rework facilities, waste is produced primarily from cleaning, coating, and depainting operations. Cleaning operations produce solvent-laden cloth and paper and spent solvent which can emit organic HAP fro m the evaporation of the solvents. Coating operations produce waste paint and waste solvent thi nner that also emit organic HAP through evaporation. Depainting operations can produce eithe r a liquid or solid waste stream depending on the type of process used. Chemical depainting pro cesses produce a liquid sludge that consists of the stripper solution and paint residue. Emissions occur from the evaporation of the solvent from the stripper solution. Abrasive media blast depainting processes produce a solid waste stream that consists of paint chips and spent blast ing media. Emissions do not directly occur from this waste stream, although particulate emiss ions are generated during the blasting

process.

Section 3.1 presents a summary of the level of control of the 1995 MACT standard and the technologies evaluated during this technology review of subpart GG. Section 3.2 presents an analysis for identified control measures to determine wh ether they qualify as “developments inpractices, processes and control technologies” for wast e storage and handling sources at

aerospace manufacturing and rework facilities.

3.1 Summary of the 1995 MACT Level of Control

The Aerospace MACT standard (subpart GG) that applies to t he waste storage and handling affected source is a work practice standard consi sting of housekeeping measures.

For waste storage and handling operations that are not al ready subject to requirements under RCRA as implemented by 40 CFR parts 260 and 261, and that a re subject to RCRA requirements as implemented in 40 CFR parts 262 through 268:

• The provisions under 40 CFR 63.744(a)(1) and (a)(2) require that spe nt cleaning solvent and spent solvent laden materials (e.g., cloth or paper a pplicators) be stored in closed

containers.

• The provisions under 40 CFR 63.744(a)(3) require that all handling an d transfer of spent cleaning solvents be done in a manner to minimize spills.

• The provisions under 40 CFR 63.748 require that all handling and tr ansfer of HAP containing wastes be done in a manner to minimize spills.

For waste storage and handling operations that are alread y subject to requirements of RCRA as implemented by 40 CFR parts 260 and 261, and that are s ubject to RCRA requirements as implemented in 40 CFR parts 262 through 268:

• The provisions of 40 CFR 63.741(e) specify that waste storage an d handling operations are not subject to the requirements of subpart GG.

Aside from the exemption of RCRA wastes at §63.741(e), the text of the 1995 Aerospace MACT does not include any definitions or other descriptions o f the operations that comprise the waste storage and handling affected source.

As described in the previous section, waste storage and han dling operations are characterized by evaporative emissions of organic HAP tha t are fugitive in nature. Thus, the EPA proposed in 1994 organic HAP emissions standards for this affec ted source, but no standards for inorganic HAP.

Based on the section 114 questionnaire responses collected pr ior to the proposed rule in 1994, 181 non-wastewater waste streams were reported. Ever y stream was controlled by housekeeping measures such as keeping the waste material i n closed drums. Thus, housekeeping

measures were established in 1994 as the MACT floor for han dling and storage of waste.

While no data were available for the effect on emissio ns from the housekeeping measures, it was expected that emissions would be reduced based on the data from California facilities for keeping cleaning solvents in closed contai ners. Consequently, housekeeping measures were used as the basis for the proposed standard.In addition, existing RCRA regulations govern handling and sto rage practices for certain

types of wastes. Since the EPA did not want to create a situation where 40 CFR part 63, subpart GG would be less stringent than RCRA regulations, the pro posed rule exempted wastes covered under the RCRA regulations.

The EPA stated at proposal in 1994 that the rationale f or the format of the proposed standards for handling and storage of waste was essentiall y the same as that for housekeeping measures for cleaning solvents. As stated in section V.F .1 of the 1994 Aerospace MACT proposal preamble: “The cleaning operation for which the EP A is proposing standards emits a variety of organic HAP. For many of these organic HAP, e mission measurement methods either do not exist or would be very expensive to implement. In additio n, the nature of some cleaning operations (e.g., hand-wipe cleaning) makes collection th rough a conveyance device difficult if not impossible. Therefore, the EPA determined that emis sion standards are not feasible for these operations.” Since no data were available to establish a n emission limitation and control equipment was not technically feasible, a work practic e format requiring housekeeping measures was selected as the most appropriate means of reducing emi ssions.

Based on these considerations, the 1994 proposed and the 1995 fi nal rule included the requirement to conduct the handling and transfer of waste i n a manner to minimize spills. In addition, the 1994 proposal required that all HAP-containing w astes be stored in closed containers. However, the EPA received numerous commen ts that the proposed requirement for closed containers was duplicative in light of existing RCR A requirements covering the same types of waste materials. The waste materials of conc ern in the development of the proposed rule (such as rags, waste paint and maskant, thinners, sludge, and used paint filters) were already subject to the RCRA requirements, according to the commen ters. As a result, the EPA deleted this provision for storage in closed containers while reta ining the provision requiring handling of waste in such a manner that minimizes spills. The sta te of the technology for waste storage at the time of the 1995 final rule was storage of waste in close d containers.

3.2 Identified Control Measures for Waste Storage and Handling

3.2.1 Add-On Control Technology or Other Equipment Not Identified and Considere d During MACT Development

As discussed in section 2, the RBLC search and the revie w of subsequent regulatory actions did not yield any new equipment or add-on control technologies that were not considered during MACT development.

3.2.2 Improvements in Add-On Control Technology or Other Equipment (That Was Identified and Considered During MACT Development)

As discussed in section 2, the RBLC search and the revie w of subsequent regulatory actions did not yield any potential developments or improv ements in add-on control technology or other equipment since the MACT development.

3.2.3 Work Practices and Procedures Not Identified and Considered During MACT DevelopmentMany of the state and local VOC regulations and MACT st andards that were reviewed

contain work practice standards for waste storage and hand ling based on housekeeping measures. Some of these work practice standards include additional pro visions that were apparently designed to improve implementation of the housekeeping me asures. These work practice

standards are discussed below.

Many of the VOC regulations and MACT standards require th at VOC/HAP-containing waste materials be kept in closed containers. These pro visions are most often a component of the solvent cleaning requirements, and include the requirement for fresh and spent solvent and solvent-laden paper and cloths to be kept in closed containe rs. In the Aerospace MACT, cleaning operations are a separate affected source, and the provis ions for that affected source include these same requirements. In this way, there is some o verlap in the Aerospace MACT between the cleaning operations affected source and the waste storage a nd handling affected source.

As discussed in section 3.1, the EPA had previously conside red requiring all HAPcontaining wastes to be stored in closed containers but dec ided not to include this requirement in the final 1995 rule to avoid duplicating RCRA requirements. N evertheless, the EPA did retain a similar requirement for the cleaning operations affected s ource. Based on these facts, we do not believe that storing all HAP-containing wastes in closed containers qualifies as a “development in practices, processes and control technologies” worthy of further consideration in the technology review of the waste storage and handling affe cted source.

One state rule includes, in addition to a requirement to m inimize spills, a requirement to clean up spills of fresh and spent cleaning solvent and oth er VOC-containing material immediately. While this measure might produce a marginal r eduction in emissions, an effective program to prevent spills would be expected to render this r equirement moot. In addition, it is likely that immediate clean-up of such spills would be required at most facilities under standard operating procedures to minimize worker exposure to solvents and for general cleanliness. Although not explicitly discussed in the background document s prepared for the Aerospace MACT, rapid clean-up of spills is not a new concept, and we do not believe that regulation is necessary to induce this practice. Due to these considerat ions, we do not believe immediate clean-up of spills qualifies as a “development in practi ces, processes and control technologies” worthy of further consideration in the technology review of the waste storage and handling

affected source.