# Standards of Performance for New Stationary Sources and Emission Guidelines for Existing Sources: Other Solid Waste Incineration Units

> Briefs, arguments, decisions, and more.

URL: https://www.frixlaw.com/law-library/documents/fr%3A04-26741

## Record

- **Collection:** Federal Register
- **Document type:** Proposed Rule
- **Published:** December 9, 2004
- **Citation:** 69 FR 71472

## Text

ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 60
[OAR-2003-0156; FRL-7845-4]
RIN 2060-AG31
Standards of Performance for New Stationary Sources and Emission Guidelines for Existing Sources: Other Solid Waste Incineration Units

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Proposed rules.

SUMMARY:

The EPA is proposing new source performance standards (NSPS) and emission guidelines for new and existing “other” solid waste incinerators (OSWI) units. The proposed rules fulfill the requirements of sections 111 and 129 of the Clean Air Act (CAA), which require EPA to promulgate NSPS and emission guidelines for solid waste incineration units. These requirements are based on the Administrator's determination that these waste incinerators cause, or contribute significantly to, air pollution that may reasonably be anticipated to endanger public health or welfare. The proposed rules, which address only nonhazardous solid wastes, would protect public health by reducing exposure to air pollution.

DATES:

Comments must be received on or before February 7, 2005.

Public Hearing.
If anyone contacts EPA by December 29, 2004, requesting to speak at a public hearing, EPA will hold a public hearing on January 10, 2005. If you are interested in attending the public hearing, contact Ms. Kelly Hayes at (919) 541-5578 to verify that a hearing will be held.

ADDRESSES:

Submit your comments, identified by Docket ID No. OAR-2003-0156, by one of the following methods:

Federal eRulemaking Portal: http://www.regulations.gov.
Follow the on-line instructions for submitting comments.

Agency Web site: http://www.epa.gov/edocket.
EDOCKET, EPA's electronic public docket and comment system, is EPA's preferred method for receiving comments. Follow the on-line instructions for submitting comments.

E-mail:
Send your comments via electronic mail to
a-and-r-docket@epa.gov
, Attention Docket ID No. OAR-2003-0156.

Facsimile:
Fax your comments to (202) 566-1741, Attention Docket ID No. OAR-2003-0156.

Mail:
Send your comments to: EPA Docket Center (EPA/DC), Environmental Protection Agency, Mailcode 6102T, 1200 Pennsylvania Ave., NW., Washington, DC 20460, Attention Docket ID No. OAR-2003-0156. Please include a total of two copies. The EPA requests a separate copy also be sent to either of the contact persons identified below (
see

FOR FURTHER INFORMATION CONTACT
). 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:
Deliver your comments to: EPA Docket Center (EPA/DC), EPA West Building, Room B108, 1301 Constitution Ave., NW., Washington, DC, 20460, Attention Docket ID No. OAR-2003-0156. Such deliveries are accepted only during the normal hours of operation (8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays), and special arrangements should be made for deliveries of boxed information.

Instructions:
Direct your comments to Docket ID No. OAR-2003-0156. The 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.epa.gov/edocket
, 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 EDOCKET, regulations.gov, or e-mail. The EPA EDOCKET and the Federal regulations.gov Web sites are “anonymous access” systems, 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 EDOCKET or 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.

Public Hearing:
If a public hearing is held, it will be held at EPA's Campus located at 109 T.W. Alexander Drive in Research Triangle Park, NC, or an alternate site nearby.

Docket:
All documents in the docket are listed in the EDOCKET index at
http://www.epa.gov/edocket.
Although listed in the index, some information is not publicly available,
i.e.
, 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 in EDOCKET or in hard copy at the EPA Docket Center (EPA/DC), EPA West Building, Room B102, 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 EPA Docket Center is (202) 566-1742.

FOR FURTHER INFORMATION CONTACT:

Ms. Mary Johnson or Mr. Fred Porter, Combustion Group, Emission Standards Division (C439-01), U.S. EPA, Research Triangle Park, North Carolina 27711; telephone number: (919) 541-5025 or (919) 541-5251; e-mail address:
johnson.mary@epa.gov
or
porter.fred@epa.gov.

Organization of This Document.
The following outline is provided to aid in locating information in this preamble.

I. General Information

A. Does This Action Apply To Me?

B. What Should I Consider as I Prepare My Comments for EPA?

II. Background Information

A. What Is the Statutory Authority for the Proposed Rules?

B. What Are New Source Performance Standards (NSPS)?

C. What Are Emission Guidelines?

D. How Are the Emission Guidelines Implemented?

III. Summary of the Proposed Rules

A. Do the Proposed Rules Apply To Me?

B. What Emission Limits Must I Meet?

C. What Operating Limits Must I Meet?

D. What Are the Other Requirements?

E. What Are the Requirements for Air Curtain Incinerators?

F. What Title V Permit Requirements Must I Meet?

IV. Rationale for the Proposed Rules

A. How Did EPA Determine Which Pollution Sources Would Be Regulated Under the Proposed Rules?

B. How Did EPA Select the Pollutants To Be Regulated?

C. How Did EPA Select the Format for the Proposed Rules?

D. How Did EPA Determine the Proposed Emission Limits for New OSWI Units?

E. How Did EPA Determine the Proposed Emission Limits for Existing OSWI Units?

F. How Did EPA Determine Testing and Monitoring Requirements for the Proposed Rules?

G. How Did EPA Determine Compliance Times for the Proposed Rules?

H. How Did EPA Determine the Required Records and Reports for the Proposed Rules?

I. How Did EPA Determine Operator Training and Qualification Requirements for the Proposed Rules?

J. How Did EPA Determine the Waste Management Plan Requirements for the Proposed Rules?

K. How did EPA Determine the Siting Requirements for New Units for the Proposed Rules?

V. Impacts of the Proposed Rules for New Units

A. What Are the Air Impacts?

B. What Are the Water and Solid Waste Impacts?

C. What Are the Energy Impacts?

D. What Are the Cost and Economic Impacts?

VI. Impacts of the Proposed Rules for Existing Units

A. What Are the Air Impacts?

B. What Are the Water and Solid Waste Impacts?

C. What Are the Energy Impacts?

D. What Are the Cost and Economic Impacts?

VII. 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 That Significantly Affect Energy Supply, Distribution or Use

I. National Technology Transfer Advancement Act

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does This Action Apply To Me?

Regulated Entities.
Categories and entities potentially regulated by the proposed rules are very small municipal waste combustion (VSMWC) units and institutional waste incineration (IWI) units. The OSWI emission guidelines and NSPS would affect the following categories of sources:

Category
NAICS code
SIC code
Examples of potentially regulated entities

Any State, local, or Tribal government using a VSMWC unit as defined in the regulation
562213, 92411
4953, 9511
Solid waste combustion units burning municipal waste collected from the general public and from residential, commercial, institutional, and industrial sources.

Institutions using an IWI unit as defined in the regulations
922, 6111, 623, 7121
9223, 8211, 7999
Correctional institutions, primary and secondary schools, camps and national parks.

Any Federal government agency using an OSWI unit as defined in the regulations
928
9711
Department of Defense (labs, military bases, munition facilities).

Any college or university using an OSWI unit as defined in the regulations
6113, 6112
8221, 8222
Universities, colleges and community colleges.

Any church or convent using an OSWI unit as defined in the regulations
8661
8131
Churches and convents.

Any civic or religious organization using an OSWI unit as defined in the regulations
8641
8134
Civic associations and fraternal associations.

This table is not intended to be exhaustive, but rather provides a guide for readers regarding entities likely to be regulated by the proposed rules. To determine whether your facility would be regulated by the proposed rules, you should examine the applicability criteria in 40 CFR 60.2885 through 60.2888 of subpart EEEE, and 40 CFR 60.2991 through 60.2994 of subpart FFFF. If you have any questions regarding the applicability of the proposed rules to a particular entity, contact either of the persons listed in the preceding
FOR FURTHER INFORMATION CONTACT
section.

B. What Should I Consider as I Prepare My Comments for EPA?

1.
Submitting CBI.
Do not submit information that you consider to be CBI electronically through EDOCKET, regulations.gov, or e-mail. Send or deliver information identified as CBI to only the following address: Ms. Mary Johnson, c/o OAQPS Document Control Officer (Room C404-02), U.S. EPA, Research Triangle Park, NC 27711, Attention Docket ID No. OAR-2003-0156. 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 marked as CBI will not be disclosed except in accordance with procedures set forth in 40 CFR part 2.

If you have any questions about CBI or the procedures for claiming CBI, please consult either of the persons identified in the
FOR FURTHER INFORMATION CONTACT
section.

2.
Tips for Preparing Your Comments.
When submitting comments, remember to:

a. Identify the rulemaking by docket number and other identifying information (subject heading,
Federal Register
date and page number).

b. Follow directions. The EPA may ask you to respond to specific questions or organize comments by referencing a Code of Federal Regulations (CFR) part or section number.

c. Explain why you agree or disagree; suggest alternatives and substitute language for your requested changes.

d. Describe any assumptions and provide any technical information and/or data that you used.

e. If you estimate potential costs or burdens, explain how you arrived at your estimate in sufficient detail to allow for it to be reproduced.

f. Provide specific examples to illustrate your concerns, and suggest alternatives.

g. Explain your views as clearly as possible, avoiding the use of profanity or personal threats.

h. Make sure to submit your comments by the comment period deadline identified.

Docket.
The docket number for the proposed NSPS (40 CFR part 60, subpart EEEE) and emission guidelines (40 CFR part 60, subpart FFFF) is Docket ID No. OAR-2003-0156.

World Wide Web (WWW).
In addition to being available in the docket, an electronic copy of the proposed rules is available on the WWW through the

Technology Transfer Network Web site (TTN Web). Following signature, EPA will post a copy of the proposed rules on the TTN's policy and guidance page for newly proposed or promulgated rules at
http://www.epa.gov/ttn/oarpg.
The TTN provides information and technology exchange in various areas of air pollution control. If you need more information regarding the TTN, call the TTN Help line at (919) 541-5384.

II. Background Information

A. What Is the Statutory Authority for the Proposed Rules?

Section 129 of the CAA, entitled “Solid Waste Combustion,” requires EPA to develop and adopt NSPS and emission guidelines for solid waste incineration units pursuant to CAA section 111. Section 111(b) of the CAA requires EPA to establish NSPS for new sources, and CAA section 111(d) requires EPA to establish procedures for States to submit plans for implementing emission guidelines for existing sources. Under CAA section 111, NSPS and emission guidelines must be developed for new and existing stationary sources that cause or contribute significantly to air pollution that may reasonably be anticipated to endanger public health or welfare.

Congress specifically added section 129 to the CAA to address concerns about emissions from solid waste combustion units. Section 129 of the CAA requires EPA to promulgate emissions standards and other requirements for “each category of solid waste incineration unit.” Section 129(a)(1) of the CAA identifies five categories of solid waste incineration units:

(1) Units with a capacity of greater than 250 tons per day (tpd) combusting municipal waste;

(2) Units with a capacity equal to or less than 250 tpd combusting municipal waste;

(3) Units combusting hospital, medical and infectious waste;

(4) Units combusting commercial or industrial waste; and

(5) Unspecified “other categories of solid waste incineration units.”

Section 129(g)(1) of the CAA identifies several types of units that are not solid waste incineration units, including units required to have a permit under section 3005 of the Solid Waste Disposal Act (SWDA); materials recovery facilities; certain qualifying small power production facilities or qualifying cogeneration facilities which burn homogeneous waste; and certain air curtain incinerators that meet opacity limitations established by EPA.

For each category of incineration unit identified under CAA section 129, EPA must establish numerical emission limits for at least nine specified pollutants (particulate matter (PM), sulfur dioxide (SO
2
), hydrogen chloride (HCl), nitrogen oxides (NO
X
), carbon monoxide (CO), lead (Pb), cadmium (Cd), mercury (Hg), and dioxins and dibenzofurans), and for opacity as appropriate. Section 129 of the CAA provides EPA with the discretion to establish emission limitations for other pollutants as well. (
See
CAA section 129(a)(4).)

Under CAA section 129, the NSPS and emission guidelines adopted for solid waste combustion units must reflect the maximum achievable control technology (MACT). Accordingly, EPA's standards under CAA section 129 must “* * * reflect the maximum degree of reduction in emissions of [the listed] air pollutants * * * that the Administrator, taking into consideration the cost of achieving such emissions reductions, and any non-air quality health and environmental impacts and energy requirements, determines is achievable for new or existing units in each category * * *.” (
See
CAA section 129(a)(2).) However, the standards for new units must not be less stringent than the emissions control that is achieved in practice by the best controlled similar unit, and the standards for existing sources must not be less stringent than the average emissions limitations achieved by the best performing 12 percent of units in the category.

Regulations have been developed for each of the listed categories of solid waste incineration unit except for the “other categories of solid waste incineration units.” Today's notice proposes regulations for these “other” (or OSWI) units. Three previous notices have been published regarding OSWI regulatory development (58 FR 31358, June 2, 1993; 58 FR 58498, November 2, 1993; 65 FR 67367, November 9, 2000). In the November 9, 2000 notice, EPA revised the OSWI regulatory schedule to promulgate regulations by November 2005. This was subsequently incorporated into a consent decree, requiring that EPA propose regulations for the OSWI source category by November 30, 2004, and promulgate by November 30, 2005.

B. What Are New Source Performance Standards?

The NSPS for solid waste incineration units are developed according to CAA sections 111 and 129. An NSPS applies to new stationary sources of emissions, that is, sources for which construction begins after a standard is proposed or sources that are modified on or after a specified date. The key elements in an NSPS are generally defined as follows:

1.
Source category to be regulated
means the industries or types of processes that are regulated. Section 129 of the CAA requires EPA to regulate several categories of incinerators specifically listed in CAA section 129 and to regulate “other categories of solid waste incineration units” (known as OSWI). The proposed NSPS applies to the OSWI category, which is VSMWC units and IWI units.

2.
Affected facility
means a solid waste incineration unit that will be subject to the NSPS. The proposed NSPS would affect each individual OSWI unit.

3.
Pollutants to be regulated
means the particular substances emitted by the affected facility that the NSPS regulates. Section 129 of the CAA specifies nine pollutants: Cd, CO, dioxins/furans, PM, HCl, Pb, Hg, NO
X
, and SO
2
. Opacity standards may also be required as appropriate. The CAA section 129 pollutants represent the minimum requirements; EPA can add other pollutants, if appropriate, but has determined that doing so in regulating the OSWI category is unnecessary because other potentially relevant pollutants are adequately addressed by control of the pollutants to be regulated.

4.
Maximum achievable control technology
means the technology on which the emission standards will be based. Section 129(a)(2) of the CAA specifies that standards be based on “* * * the maximum degree of reduction in emissions * * * that the Administrator, taking into consideration the cost of achieving such emission reduction, and any non-air quality health and environmental impacts and energy requirements, determines is achievable * * *.” (Note that solid waste incineration standards under CAA section 129 are different from typical NSPS under CAA section 111, which are based on “best demonstrated technology” rather than MACT.)

5.
Format for the standards
means the form in which the standards are expressed; for example, as pollutant concentration emission limits, as a percent reduction in emissions, or as equipment or work practice standards. Section 129 of the CAA also directs EPA to establish siting requirements for new incineration units and operator certification and training requirements for all units.

6.
Emission limits
generally means limits based on the level of reduction that the MACT can achieve. Only in unusual cases do standards require that

a specific technology be used. In general, the source owner or operator may select any method for complying with the limits.

7.
Other considerations in addition to emission limits for NSPS
usually include: Standards for visible emissions, modification and reconstruction provisions, monitoring requirements, performance test methods and compliance procedures, and reporting and recordkeeping requirements.

C. What Are Emission Guidelines?

Emission guidelines are similar to NSPS, except that they apply to existing sources. That is, they apply to sources for which construction began on or before the date a standard is proposed or that are modified before a specified date. Unlike NSPS, the emission guidelines are not enforceable until EPA approves a State plan or adopts a Federal plan for implementing and enforcing them, and the State or Federal plan becomes effective.

D. How Are the Emission Guidelines Implemented?

When standards of performance for solid waste incineration units are promulgated under CAA sections 111 and 129, the CAA requires States under CAA sections 111(d) and 129(b) to submit plans that: (1) Establish emission standards for existing sources, and (2) provide for implementation and enforcement of the emission standards.

States are required to adopt and submit to the Administrator a State plan implementing the emission guidelines within 1 year after the promulgation of the guidelines (CAA section 129(b)(2)). The State plan carries out and provides for enforcing the emission guidelines. Section 129 of the CAA provides that the State plan for existing incineration units must be at least as protective as the emission guidelines and must provide for compliance by affected facilities no later than 3 years after the effective date of State plan approval, but no later than 5 years after EPA promulgates the guidelines. Section 111(d) of the CAA further requires that the procedures for submitting a State plan must be similar to the procedures for submitting State implementation plans under CAA section 110. (The EPA has established specific procedures in 40 CFR part 60, subpart B.) Sections 111(d) and 129(b) of the CAA also require EPA to develop, implement, and enforce a Federal plan if a State fails to submit a satisfactory State plan.

III. Summary of the Proposed Rules

A. Do the Proposed Rules Apply to Me?

The proposed rules apply to you if you own or operate either of the following:

(1) An incineration unit burning municipal solid waste (MSW) (as defined in CAA section 129, 40 CFR 60.2977 of subpart EEEE, and 40 CFR 60.3078 of subpart FFFF) with a capacity less than 35 tpd, or

(2) An incineration unit located at an institutional facility burning institutional waste (as defined in 40 CFR 60.2977 of subpart EEEE and 40 CFR 60.3078 of subpart FFFF) generated at that facility.

If your incineration unit is currently meeting emission limitations and other requirements of another CAA section 129 regulation (
i.e.
, small or large municipal waste combustion (MWC) units; hospital, medical, infectious waste incineration units (HMIWI units); or commercial and industrial solid waste incineration units (CISWI units)), the proposed rules do not apply to you. Likewise, if your institutional combustion unit is covered under the CAA section 112 National Emission Standards for Hazardous Air Pollutants (NESHAP) for industrial, commercial, and institutional boilers and process heaters (boilers NESHAP), it would not be subject to the proposed rules. Certain types of combustion units listed in 40 CFR 60.2887 of subpart EEEE and 40 CFR 60.2993 of subpart FFFF are also excluded from the proposed rules.

If you began construction of your OSWI unit on or before December 9, 2004, it is considered an existing OSWI unit and would be subject to the proposed emission guidelines. If you began construction of your OSWI unit after December 9, 2004, it is considered a new OSWI unit and would be subject to the proposed NSPS.

If you began reconstruction or modification of your OSWI unit prior to [DATE 6 MONTHS AFTER DATE FINAL RULE IS PUBLISHED IN THE
Federal Register
], it is considered an existing unit and would be subject to the emission guidelines. Likewise, if you began reconstruction or modification of your OSWI unit on or after [DATE 6 MONTHS AFTER DATE FINAL RULE IS PUBLISHED IN THE
Federal Register
], it is considered a new OSWI unit and would be subject to the NSPS.

B. What Emission Limits Must I Meet?

As the owner or operator of a new or existing OSWI unit, you would be required to meet the emission limits specified in Table 1 of this preamble. You would be required to conduct a performance test to show compliance within 60 days after a new OSWI unit reaches the charge rate at which it will operate, but no later than 180 days after the unit's initial startup.

As the owner or operator of an existing OSWI unit, you would be required to meet the emission limits specified in Table 1 of this preamble within 3 years after the effective date of State plan approval or when EPA promulgates a Federal plan, but no later than 5 years after [DATE THE FINAL RULE IS PUBLISHED IN THE
Federal Register
].

Table 1.—Emission Limits for New and Existing OSWI Units

For these pollutants

You must meet these emission limits
a

And determine compliance using these methods
b, c

Cd
18 micrograms per dry standard cubic meter (μg/dscm)
EPA Method 29

CO
5.0 parts per million dry volume (ppmdv)
EPA Methods 10, 10A or 10B

Dioxins/Furans (total mass basis)
33 nanograms per dry standard cubic meter (ng/dscm)
EPA Method 23

HCl
3.7 ppmdv
EPA Method 26A

Pb
226 μg/dscm
EPA Method 29

Hg
74 μg/dscm
EPA Method 29

Opacity
10%
EPA Method 9

NO
X

103 ppmdv

EPA Methods 7, 7A, 7C, 7D, or 7E
d

PM
0.013 grains per dry standard cubic foot (gr/dscf)
EPA Method 5 or 29

SO
2

3.1 ppmdv

EPA Method 6 or 6C
e

a
All emission limits (except opacity) are measured at 7 percent oxygen, dry basis at standard conditions.

b
These methods are in 40 CFR part 60, appendix A.

c
Compliance with the CO emission limit is determined on a 3-hour rolling average basis using continuous emission monitoring system data. Compliance for the other pollutants' emission limits is determined by stack testing.

d
ASME PTC 19-10-1981—Part 10 is an acceptable alternative to only Methods 7 and 7C.

e
ASME PTC 19-10-1981—Part 10 is an acceptable alternative to Method 6 only.

C. What Operating Limits Must I Meet?

If you use a wet scrubber to comply with the emission limits, you would be required to establish the maximum and minimum site-specific operating limits indicated in Table 2 of this preamble. You would then be required to operate the OSWI unit so that the charge rate does not exceed the established maximum charge rate. You would be required to operate the wet scrubber so that the pressure drop or amperage, scrubber liquor flow rate, and scrubber liquor pH do not fall below the minimum established operating limits.

Table 2.—Operating Limits for New and Existing OSWI Units Using Wet Scrubbers

For these operating parameters
You must establish these operating limits
And monitor continuously using these recording times

Charge rate
Maximum charge rate
Every hour

Pressure drop across the wet scrubber, or amperage to the wet scrubber
Minimum pressure drop or amperage
Every 15 minutes

Scrubber liquor flow rate
Minimum flow rate
Every 15 minutes

Scrubber liquor pH
Minimum pH
Every 15 minutes

Note:
Compliance is determined on a 3-hour rolling average basis, except charge rate for batch incinerators, which is determined on a 24-hour basis.

If you use an air pollution control device other than a wet scrubber to comply with the emission limits, you would be required to petition the Administrator for other site-specific operating limits to be established during the initial performance test and continuously monitored thereafter. The information you must include in your petition is described in 40 CFR 60.2917 of subpart EEEE and 40 CFR 60.3024 of subpart FFFF.

D. What Are the Other Requirements?

As the owner or operator of a new or existing OSWI unit, you would be required to meet the following additional requirements.

Siting Analysis (new units only):

• Submit a report that evaluates site-specific air pollution control alternatives that minimize potential risks to public health or the environment, considering costs, energy impacts, nonair environmental impacts, or any other factors related to the practicability of the alternatives.

Waste Management Plan:

• Submit a written plan that identifies both the feasibility and the methods used to reduce or separate certain components of solid waste from the waste stream to reduce or eliminate toxic emissions from incinerated waste.

Operator Training and Qualification Requirements:

• Qualify operators or their supervisors (at least one per facility) by ensuring that they complete an operator training course and annual review or refresher course.

Testing Requirements:

• Conduct initial performance tests for Cd, CO, dioxins/furans, HCl, Pb, Hg, NO
X
, opacity, PM, and SO
2
and establish operating limits (
i.e.
, maximum or minimum values for operating parameters).

• Conduct annual performance tests for all nine pollutants and opacity. (An owner or operator may conduct less frequent testing if the facility demonstrates that it is in compliance with the emission limits for three consecutive performance tests.)

Monitoring Requirements:

• Continuously monitor CO emissions.

• If using a wet scrubber to comply with the emission limits, continuously monitor the following operating parameters: charge rate, pressure drop across the wet scrubber (or amperage), and scrubber liquid flow rate and pH.

• If something other than a wet scrubber is used to comply with the emission limits, monitor other operating parameters, as approved by the Administrator.

Recordkeeping and Reporting Requirements:

• Maintain for 5 years records of the initial performance tests and all subsequent performance tests, operating parameters, any maintenance, the siting analysis (for new units only), and operator training and qualification. Each record must be kept on site for at least 2 years. The records may be kept off site for the remaining 3 years.

• Submit the results of the initial performance tests and all subsequent performance tests and values for the operating parameters.

• Submit annual compliance reports and semiannual reports of any deviations from the emission limits, operating limits, or other requirements.

• Apply for and obtain a title V operating permit.

E. What Are the Requirements for Air Curtain Incinerators?

The proposed rules establish opacity limitations for air curtain OSWI units burning:

• 100 percent wood wastes,

• 100 percent clean lumber,

• 100 percent yard waste, or

• 100 percent mixture of only wood waste, clean lumber, and/or yard waste.

The opacity limit is 10 percent. However, 35 percent opacity is allowed during startup periods that are within the first 30 minutes of operation. Air curtain incinerators burning only these materials would be required to meet the opacity limits and apply for and obtain a title V operating permit, but would be exempt from the other requirements of the proposed rules.

Air curtain incinerators burning other institutional waste or municipal waste would be required to meet the proposed rules including all emission limits in Table 1 of this preamble and the associated testing, permitting, monitoring, recordkeeping, and reporting requirements.

F. What Title V Permit Requirements Must I Meet?

All new and existing OSWI units would be required to apply for and obtain a title V permit. These title V operating permits would assure compliance with all applicable requirements for OSWI units, including all applicable CAA section 129 requirements. (
See
40 CFR 70.6(a)(1), 70.2, 71.6(a)(1) and 71.2.)

When a CAA section 129 source is required to apply for a title V permit depends on when the source first becomes subject to the relevant title V

permits program. If an OSWI unit is a new unit and is not subject to an earlier permit application deadline, a complete title V permit application must be submitted on or before one of the following dates:

1. For an OSWI unit that commenced operation as a new source as of the promulgation date of 40 CFR part 60, subpart EEEE, then a complete title V permit application must be submitted not later than 12 months after the promulgation date of 40 CFR part 60, subpart EEEE.

2. For an OSWI unit that does not commence operation as a new source until after the promulgation of 40 CFR part 60, subpart EEEE, then a complete title V permit application must be submitted not later than 12 months after the date the OSWI unit commences operation as a new source. (
See
CAA section 503(c) and 40 CFR 70.5(a)(1)(i) and 71.5(a)(1)(i).)

If your OSWI unit is an existing unit and is not subject to an earlier permit application deadline, a complete title V permit application must be submitted by the earlier of the following dates:

1. Twelve months after the effective date of any applicable EPA-approved CAA section 111(d)/129 plan (
i.e.
, an approved State or Tribal plan that implements the OSWI emission guidelines).

2. Twelve months after the effective date of any applicable Federal plan.

3. Thirty-six months after promulgation of 40 CFR part 60, subpart FFFF.

For any existing OSWI unit not subject to an earlier permit application deadline, the application deadline of 36 months after the promulgation of 40 CFR part 60, subpart FFFF, applies regardless of whether or when any applicable Federal plan is effective, or whether or when any applicable CAA section 111(d)/129 plan is approved by EPA and becomes effective. (
See
CAA sections 129(e), 503(c), 503(d), and 502(a) and 40 CFR 70.5(a)(1)(i) and 71.5(a)(1)(i).)

If your OSWI unit is subject to title V as a result of some triggering requirement(s) other than those mentioned above (for example, an OSWI unit may be a major source or part of a major source), then your unit may be required to apply for a title V permit prior to the deadlines specified above. If more than one requirement triggers a source's obligation to apply for a title V permit, the 12-month time frame for filing a title V permit application is triggered by the requirement that first causes the source to be subject to title V. (
See
CAA section 503(c) and 40 CFR 70.3(a) and (b), 70.5(a)(1)(i), 71.3(a) and (b), and 71.5(a)(1)(i).)

For additional background information on the interface between CAA section 129 and title V, including EPA's interpretation of section 129(e), information on updating existing title V permit applications and reopening existing title V permits, see the final Federal Plan for Commercial and Industrial Solid Waste Incinerators, October 3, 2003 (68 FR 57518, 57532).

IV. Rationale for the Proposed Rules

A. How Did EPA Determine Which Pollution Sources Would Be Regulated Under the Proposed Rules?

Section 129(a) of the CAA requires the promulgation of standards for several categories of solid waste combustion units, including units combusting municipal waste; units combusting hospital, medical and infectious waste; units combusting commercial or industrial waste; and unspecified “other categories of solid waste incineration units.” The subject of the proposed rules is the unspecified other categories of solid waste incineration units.

One important part of EPA's rulemaking process is determining what universe of sources will be subject to regulation. With regard to OSWI units, the statutory provisions of CAA sections 129(a), (g) and (h) make it clear that EPA must determine, as a part of the regulatory process, (1) where to draw the line between combustion units potentially subject to regulation under CAA section 129 and combustion units potentially subject to regulation under other statutory authority (such as CAA section 112(d)), and (2) to which categories of solid waste combustion units the standards for “other categories of solid waste incineration units” apply. For example, the reference in CAA section 129(g)(1) to a permit issued under section 3005 of the SWDA, refers to units burning hazardous solid waste. This effectively limits the scope of EPA's authority under CAA section 129 to the regulation of solid waste incineration units that burn nonhazardous solid waste. Similarly, the language of CAA section 129(h) makes clear the Congressional intent for CAA regulation under CAA section 129 or CAA section 112 to be mutually exclusive. Accordingly, sources subject to CAA section 112 standards do not constitute OSWI (the dividing line between boilers regulated under CAA section 112 and OSWI is discussed in detail below). Absence of regulation under CAA section 112, however, is not determinative of what constitutes an OSWI unit. Inherent in EPA's implementation of CAA section 129 is the discretion to reasonably define what constitutes the statutorily undefined other categories of solid waste incineration units and to determine which of these other units warrant regulation under CAA section 129.

In response to the requirement to publish a schedule for regulation of other categories of solid waste incineration units, a
Federal Register
notice (58 FR 31358, June 2, 1993) was published that proposed a regulatory schedule and a draft list of potential subcategories for consideration of regulation under OSWI standards. After receiving comments on the June 1993 notice, another
Federal Register
notice (58 FR 58498, November 2, 1993) was published to include comments received on the draft category list and proposed regulatory schedule. The November 1993 notice listed the following potential subcategories of OSWI:

(1) Very small municipal waste combustion units;

(2) Residential incinerators;

(3) Agricultural waste incinerators;

(4) Wood waste incinerators;

(5) Construction and demolition waste incinerators;

(6) Crematories; and

(7) Contaminated soil treatment facilities.

A third
Federal Register
notice (65 FR 67357, November 9, 2000) was published that revised the regulatory schedule. The third notice also noted that, as additional information is collected and assessed, EPA may add or delete subcategories within the OSWI category.

Since publication of the third
Federal Register
notice, EPA has gathered additional information and updated the inventory of possible OSWI units through review of multiple Federal and State databases, literature and permit searches, and contacts with State agencies, incinerator manufacturers, trade associations, and other stakeholders. The following discussion details EPA's current assessment of each of the seven potential subcategories previously identified as under consideration for regulation within the OSWI category. Eight additional subcategories EPA has considered for regulation within the OSWI category are also discussed.

EPA recognizes that there are some subclasses of incinerators that we considered for regulation within the OSWI category that should be handled differently due to unusual circumstances (
e.g.
, unique geographic or climatic factors, used only during emergencies) that would prevent those

incinerators from having the option of using an alternative waste disposal method that our assessment indicates would be lower in cost than complying with the proposed rule. We have attempted to address these subclasses of incinerators accordingly. It has come to our attention that there exists a subclass of IWI that burn national security documents and that this subclass should be considered for potential exclusion from regulation within the OSWI category. We specifically request comment on whether this is an appropriate subclass of incinerators for exclusion.

We also request comment on whether other such subclasses may exist and the precise nature of any special and/or extenuating circumstances. Therefore, in order to make such a determination, the specific information that we are requesting from commenters includes unit location; unit capacity; age of unit; type of waste burned (
e.g.
, paper waste, garbage, laboratory waste, etc.); amount of waste burned per week; frequency and hours of operation per week; unit design characteristics (
e.g.
, single chamber, multi-chamber, presence of afterburner or control technology); an outline of routine maintenance activities to ensure good combustion within the unit; availability and description of test data; availability and cost of local commercial waste collection services; and potential economic burden associated with the proposed rule. In particular, we are interested in this information for very small units (
e.g.
, IWI units with capacities less than 0.5 ton per day). Finally, we request specific information on the nature (
e.g.
, private or public elementary school, not-for-profit) and size (
e.g.
, number of students, members, employees) of the institutions that own affected units, as well as their sources of funding (
e.g.
, county, State, Federal, tuition fees), the size of their overall budget (or revenue for profit-making entities), and the current cost of waste disposal (including the operating, maintenance, and anticipated capital costs).

1. Very Small Municipal Waste Combustion Units

Section 129 of the CAA identifies and defines “municipal waste” as a distinct type of waste. The proposed rules adopt the CAA section 129 definition of municipal waste. Municipal waste, as defined in CAA section 129 and the proposed rules, is:

“refuse (and refuse-derived fuel) collected from the general public and from residential, commercial, institutional, and industrial sources consisting of paper, wood, yard wastes, food wastes, plastics, leather, rubber, and other combustible materials and non-combustible materials such as metal, glass and rock, provided that: (A) The term does not include industrial process wastes or medical wastes that are segregated from such other wastes; and (B) an incineration unit shall not be considered to be combusting municipal waste for purposes of this subpart if it combusts a fuel feed stream, 30 percent or less of the weight of which is comprised, in aggregate, of municipal waste * * *.”

Municipal waste, therefore, is waste that has been “collected from” various solid waste sources or generators.

Very small municipal waste combustion units are typically owned or operated by municipalities, such as towns, cities, or counties. The VSMWC units are units that are not covered by the other CAA section 129 MWC regulations for small (35 to 250 tpd) or large (greater than 250 tpd) MWC units already established (40 CFR part 60 subparts Cb, Ea, Eb, AAAA, and BBBB). The EPA's research indicates that, for the most part, VSMWC units are no longer economical and the majority of them have closed down. Vendors and State agencies have indicated that new purchases and installations of VSMWC units are extremely rare, and that no growth or negative growth is the expected trend for the future. However, the EPA was able to identify a small population of existing VSMWC units.

As mentioned earlier, the larger MWC units (
i.e.
, 35 tpd or greater) are already regulated. As a result, EPA is including VSMWC units as a subcategory of OSWI for regulation.

2. Residential Incinerators

The EPA's research indicates that burning of household trash by individual households does not occur in conventional “incinerators,” but, rather, in burn barrels. Burn barrels are typically modified fifty-five gallon steel drums. They have no provisions for regulating air supply to the waste being burned and have no pollution control devices. They are typically used in rural areas where burning household trash may be viewed as more convenient than taking it to a landfill or having a waste management service collect it.

If EPA were to regulate residential burn barrels as a subcategory of OSWI, the costs necessary to comply with the proposed rules would effectively rule out the use of burn barrels. Any regulation established under CAA section 129 requires that sources, at a minimum, undertake operator training, perform emissions testing, and complete permitting, monitoring, recordkeeping and reporting duties. The annual cost of these activities alone would add up to several thousands of dollars per year. As a result, regulation under section 129 would effectively eliminate the use of residential burn barrels as a legal method of trash disposal.

While this might, at first, seem a desirable outcome, in those rural areas where State and local governments have not provided appropriate alternatives, it could lead to even greater problems if residents turned to open burning, littering, or dumping. This could result because households that use burn barrels to dispose of waste may be located in areas where convenient waste disposal alternatives do not exist. As a result, if the use of burn barrels is effectively prohibited by Federal regulation, households could turn to disposing of trash along a roadside (littering), in a field or woodland, or resorting to open burning. Littering and dumping, besides being unsightly, pose significant other problems, such as potential contamination of streams or other water bodies, and attracting vermin and wild animals, which could contribute to disease transmission. Open burning presents the same air pollution problems as barrel burning and can lead to an increased likelihood of accidental fires. Therefore, Federal regulation of residential barrel burning could lead to a number of undesirable consequences where effective local alternatives do not exist.

The EPA believes that its overriding responsibility must be to promote the use of environmentally sound integrated waste management practices. Effective management of the burning of household waste in rural areas will require the development of suitable waste disposal alternatives as well as the development of a public education effort to inform people of the environmental impacts associated with barrel burning and open burning. It should be noted that regulating open burning is beyond the scope of CAA section 129, since open burning is not done in an incinerator. Most importantly, because uncontrolled burning of household waste occurs in millions of households across rural America, programs to reduce or eliminate this practice can only be effectively managed at the local level through the development of locally based solutions that combine public education, with the development of local infrastructure for waste disposal. In many areas it will also require establishing additional State and local ordinances, and locally managed compliance programs. Many of these concerns are well beyond the scope of the CAA.

Given the highly varied nature of local government, large differences in

existing waste management infrastructure and economic resources, differences in rural population density, and regional differences in practices and attitudes towards waste management, EPA has concluded that adoption of Federal regulations that would mandate use of a uniform set of waste management practices does not appear to be practical. The EPA has chosen, instead, to develop technical assistance to help states and localities design and develop waste management programs tailored to the unique needs and constraints individual communities face. As a result, EPA has decided not to include residential incinerators (
i.e.
, burn barrels) as a subcategory of OSWI for regulation.

To provide additional information about EPA's back yard burning activities, EPA has developed a back yard burning Web site, (
http://www.epa.gov/msw/backyard
), which includes background information, access to available publications, and links to related Web sites.

3. Agricultural Waste Incinerators

Agricultural residue combustion units are primarily those units that are burning rice hulls, bagasse (pressed sugar cane), and other types of biomass. The EPA's information collection efforts, however, indicate that, when burned, these agricultural residues are used as boiler fuel. As such, the boiler is regulated under the boilers NESHAP, a CAA section 112 regulation (69 FR 55218, September 13, 2004). Since sources regulated under CAA section 112 cannot be regulated by CAA section 129 also, these sources would not be subject to the proposed rules.

Manure and livestock bedding material are also considered a type of agricultural residue, and any combustion unit burning these materials could potentially be considered an agricultural residue combustion unit. However, EPA was unable to identify any such incinerators, and has encountered only anecdotal evidence and proposals for manure combustion units. In addition, these proposed units are planned as boilers for energy production and, if built, would likely be “qualifying small power producing facilities,” which are excluded from the definition of “solid waste incineration unit” in CAA section 129. Therefore, EPA is not including them as a subcategory of OSWI for regulation at this time.

4. Wood Waste Incinerators

As noted in a previous
Federal Register
notice (65 FR 67357, November 9, 2000), EPA did not anticipate the discovery of many wood residue combustion units that were not already covered by other rules. The EPA was unable to locate and identify any wood residue combustion units that are not covered by other regulations. Information collection efforts indicate that wood residue is combusted as a fuel in boilers or process heaters. In these situations, the boilers NESHAP under CAA section 112 will regulate these combustion units. To the extent that there are any incinerators that burn wood residue, they are located at sites considered to be commercial or industrial sites, and are properly covered by the CISWI NSPS and emission guidelines. Therefore, EPA is not including wood residue combustion units as a subcategory of OSWI for regulation at this time.

5. Construction and Demolition Waste Incinerators

Like some of the other potential OSWI subcategories, EPA was unable to locate and identify any construction or demolition materials combustion units. Construction and demolition materials contain cement, concrete, gypsum and other non-combustible items. As a result, construction and demolition materials are landfilled rather than burned. In addition to this, there appears to be a trend in minimizing construction site waste generation and recycling of construction and demolition materials for use in other products (
e.g.
, asphalt, mulch, soil amendment, etc.) or structures (
e.g.
, use of “antique” or “restored” woodwork or fixtures in newly constructed buildings or residences).

Since EPA has been unable to identify any construction and demolition materials combustion units and does not anticipate a future growth of these types of units, EPA is not including the construction and demolition materials combustion units as a subcategory of OSWI for regulation at this time.

6. Crematories

Crematories are used to incinerate either human or animal remains. For the purposes of this discussion, EPA differentiates between human and animal crematories.

a. Human Crematories. As mentioned previously, CAA section 129 regulations deal solely with solid waste combustion units. In considering the nature of human crematories since the previous OSWI
Federal Register
notices were published, EPA has come to the conclusion that the human body should not be labeled or considered “solid waste.” Therefore, human crematories are not solid waste combustion units, and are not a subcategory of OSWI for regulation. If EPA or States determine, in the future, that human crematories should be considered for regulation, they would be addressed under other authorities.

b. Animal Crematories. Animal crematories are those used to dispose of animal carcasses at places like veterinary clinics, animal control facilities, universities and research institutions, pet cremation services, and livestock farms such as poultry and swine farms. From the information EPA has gathered, the emissions from these units are very low when compared to other solid waste combustion units. The emissions levels from uncontrolled animal crematory units are, in fact, less than emissions after controls from other types of incinerators that are regulated, such as MWC units and HMIWI units. This is because operation of these units involves incineration of animal or pathological tissue, which consists primarily of water, with negligible or no other materials, such as plastic, wood, metals, etc. Furthermore, the units are typically very small and operated only a few hours a week.

In addition to the low emissions from these units, EPA is also concerned about biosecurity within the agricultural sector. Incineration of diseased animals is often necessary to prevent the spread of infectious diseases. Research within the agricultural community has shown that vehicles traveling among farms to collect dead animals for off-site disposal are significant disease transmission vectors. Thus, on-site incineration is often a preferred method of animal carcass disposal, since it carries no risk of disease transmission between farms. If EPA were to impose regulations that discouraged incineration relative to rendering (which, for economic reasons, requires that trucks travel between farms to pick up animal carcasses), there could be an increase in disease transmission and mortality along with the corresponding economic impacts on farmers.

In many areas there is also a lack of reasonable and economic alternatives (
e.g.
, rendering, composting, burial) to incineration. For example, burial is often prohibited due to water quality concerns and the potential for pathogen contamination. Therefore, any regulation that adds to the costs of operating an animal incinerator would mean additional costs to farmers in areas without disposal alternatives.

Taking these concerns into account, EPA has determined that the adverse impacts associated with regulation of animal crematories outweigh the benefits of regulation and these units are

not included as a subcategory of OSWI for regulation at this time.

7. Contaminated Soil Treatment Facilities

When looking into these types of units, EPA discovered a wide variety of treatment methods as well as a wide variety of facilities at which remediations were being carried out. The methods can be carried out either
in-situ
(
e.g.
, air-sparging) or
ex-situ
(
e.g.
, thermal desorption). Most treatment methods do not involve any type of combustion. Two methods involve some type of combustion device: (1) Incineration, where the soil is extracted and then burned to combust the contaminants; and (2) thermal desorption, where the contaminated soil is heated (not burned) to drive off contaminant vapors. Non-combustion treatments are far more popular, and incineration is very rarely used.

Typically, contaminants being removed from the soil are either hazardous wastes or petroleum products leaked from underground storage tanks (UST). Hazardous waste soil treatment units are covered under Resource Conservation and Recovery Act (RCRA) subtitle C programs. Petroleum products being removed from soil at small UST site remediations are subject to RCRA subtitle I. The few site remediation sites EPA had identified for possible regulation under OSWI were, as discovered through State contacts, regulated under RCRA subtitles C or I. If a unit is subject to RCRA subtitle C, it is treating hazardous waste. Hazardous waste incinerators are exempt from CAA section 129 regulation.

Subtitle I of RCRA, which covers petroleum products coming from UST, specifies stringent site-specific environmental safeguards. Since each site and the remediation thereof may require different treatment methods, subtitle I is designed to ensure a high degree of pollution control for a variety of possible treatment options and a high degree of local regulatory and citizen involvement in selecting the use of equipment and environmental safeguards. At major sources, any site remediation activity would be covered by the CAA section 112 NESHAP for site remediations. As mentioned before, any source regulated under CAA section 112 is not subject to CAA section 129.

Therefore, after assessing the information available on soil treatment facilities and units, EPA has determined that these units are regulated elsewhere. As a result, EPA is not including contaminated soil treatment facilities as a subcategory of OSWI for regulation.

8. Institutional Waste Incinerators

When reviewing the information gathered on potential subcategories of OSWI, EPA identified IWI as a type of unit that is not regulated under other rules and should be regulated under the proposed rules. The OSWI inventory shows over 350 incineration units located at institutions. However, EPA considers this a significant overestimate of the number of IWI units. The EPA's inventory information is several years old (in some cases, as much as 5-10 years old), and research indicates that the population of these types of units has been declining for years. As a result, EPA considers it likely that the actual population of IWI units actually operating today could be half, or possibly less, of what is shown by our inventory.

The inventory information shows that these IWI units are located at a variety of facilities, including schools, universities, prisons, military bases, government facilities, churches, and other institutions, and that they burn solid materials that are generated on site, such as paper, packaging, food waste, rubbish, and garbage. They are not part of the VSMWC category, because the definition of “municipal waste” in CAA section 129 is waste “collected from” establishments, whereas these IWI units burn only waste generated on site.

Moreover, these units are not covered under the CISWI rules, because CAA section 129 limits CISWI to commercial and industrial establishments, and does not include institutions. Therefore, EPA proposes to regulate IWI as a subcategory of OSWI.

Note that under the CAA section 129 definition of “municipal waste,” small incinerators that are located at commercial businesses (such as stores and restaurants) or industrial sites and that burn solid materials generated on site are not MWC units because they do not burn waste which has been “collected from.” As mentioned above, such units are properly covered under the CISWI rules, because of their location at commercial or industrial establishments.

As mentioned previously, one important part of EPA's rulemaking process is determining what universe of sources to subject to a regulation. The statutory provisions of CAA sections 129(a) and (h) make it clear that EPA must determine, as part of the regulatory process, where to draw the line between combustion units regulated under CAA section 129 and combustion units subject to regulation under other statutory authority, such as CAA section 112. The language of CAA section 129(h) makes clear the Congressional intent that nonhazardous combustion sources not be regulated under both CAA section 129 and CAA section 112. Thus, for the IWI subcategory of OSWI, EPA must determine which sources to include in the subcategory, and which sources to regulate under CAA section 112 (
e.g.
, boilers). For example, institutional boilers burning solid materials are already regulated under CAA section 112 by the boilers NESHAP (40 CFR part 63, subpart DDDDD).
1

Many of the combustion units at institutional facilities (
e.g.
, boilers or steam generating units, heaters, and incinerators) burn “solid” materials. If the solid materials in question are considered institutional waste, the units would be regulated as part of OSWI under CAA section 129. Conversely, if the materials are not considered institutional waste (
e.g.
, they are hazardous solid waste, fuel, solid materials burned for chemical or material recovery,
etc.
), the units would not be regulated under CAA section 129 but may be regulated under other statutory authority. Thus, collectively, in the process of developing the proposed rules, developing the boilers NESHAP (already promulgated), developing rules for area source boilers, promulgating requirements for electric utility steam generating units, and establishing rules applicable to other combustion sources, EPA will map the regulatory boundaries that identify which units are subject to which requirements.

1
Other such units might be subject to regulation under any number of other EPA regulations, such as: Regulations promulgated pursuant to CAA section 112(k) to control emissions from industrial, commercial and institutional boilers that are area sources; and various other regulations developed under CAA section 112 which cover combustion units burning solid materials to recover their chemical or other material constituents.

The process of determining the regulatory applicability of different rules is not unique to the OSWI category. In fact, EPA is addressing similar issues in the CISWI category (
see
69 FR 7390, February 17, 2004) and in connection with the boilers NESHAP. The identification of the scope of one rule does not necessarily define the scope of another, or preclude EPA from adjusting the regulatory division in a subsequent rule.

To define IWI units, the proposed rules include definitions of solid waste, institutional waste, and IWI units. The definition of solid waste, for the purposes of the proposed rules, is consistent with the SWDA definition and EPA's existing regulatory

definitions. It serves to define nonhazardous solid waste. The definition of “institutional waste” distinguishes between institutional waste and solid materials that should not be considered institutional waste, as well as between IWI units and non-IWI combustion units. This distinction is particularly difficult for institutional units.
2

For example, there is general agreement that the coal burned in a coal-fired boiler or steam generating unit is not a solid waste because coal is commonly thought of as a fuel. Coal is considered a fuel because it is customarily burned to recover energy (
i.e.
, heat) for some useful purpose such as to heat water or generate steam for space heating or other purposes. However, there is no such general agreement, for example, about a solid material such as paper generated on site at an institution when it is burned in a boiler at that institution to heat a building.

2
In many cases, such as MWC units and HMIWI units, the identification of the relevant wastes and the relevant units is sufficiently clear that EPA need not address the issue at length in its rule. Indeed, CAA section 129 provides specific guidance for EPA's definitions of municipal waste and medical waste, as well as municipal waste incineration units.
See
CAA section 129(g)(5) and (6). In addition, there is broad and general agreement between EPA, the regulated community, and other stakeholders regarding what materials are municipal waste and hospital, medical and infectious waste, and which combustion units belong in the respective regulatory categories.

From EPA's point of view, the nature of a material that is burned in a unit at an institutional facility is less important than how the material is burned. In the example, paper is burned to generate the heat necessary to heat a building. If the paper were not burned to generate this heat, then the facility would instead burn another material such as coal. Like the coal, the paper is burned for a useful purpose—to heat the building. Therefore, it is reasonable to consider the paper in this second example, as the coal in the first example, to be a solid fuel and distinct from institutional waste. Thus, for purposes of distinguishing institutional waste from solid fuel, its status is determined by its use, as well as by its nature. Alternatively, if the paper were burned in a combustion unit without heat recovery, its combustion would serve no useful purpose other than to effectuate destruction or disposal of an unwanted material. The EPA would then consider it appropriate to identify the paper as institutional waste, and regulate the combustion unit as an IWI unit under the proposed rules. Similarly, if a material (that is not hazardous waste) is burned in a combustion unit at an institutional facility with heat recovery, for reasons that do not include the recovery of heat for useful purposes, that material would be institutional waste and the unit would be an IWI unit and would be regulated under the proposed rules. Thus, in general, if a solid material (which is not a hazardous solid waste) is burned with heat recovery at an institutional facility to generate heat for a useful purpose, it is appropriate to consider that material not to be institutional waste, and not to regulate the device as an OSWI unit under CAA section 129. See the recent CISWI notice (69 FR 7390, February 17, 2004) for additional rationale for EPA's discretion to develop definitions under CAA section 129 that distinguish between solid waste incineration units and other combustion units.

The EPA has determined that for purposes of the IWI subcategory of OSWI units, the critical consideration in determining whether the unit is burning institutional waste is the primary function of the combustion unit; and the primary indicator of function is whether or not a unit is designed and operated to recover heat for a useful purpose. That is, if the unit located at an institutional facility combusts material without heat recovery (functions primarily as an incineration unit), then the material burned in that unit is institutional waste. Similarly, if a material is burned in a unit at an institutional facility for reasons that do not include the recovery of heat for useful purposes, that material is institutional waste and the unit is an IWI unit. However, if the unit combusts material with heat recovery for a useful purpose, then the material burned is not institutional waste, and the combustion unit would not be subject to the proposed rules. By specifically defining IWI units to include only units that behave like incinerators, EPA can appropriately identify the scope of regulation of combustion units at institutional facilities under CAA section 129.

In addition to units that combust materials without heat recovery, the definition of institutional waste in the proposed rules also includes materials that are burned in a unit at an institutional facility that is followed by external waste heat recovery only (
i.e.
, no heat recovery in the combustion firebox). The boilers NESHAP covers combustion units at institutional facilities that burn solid materials and recover heat in the combustion firebox. Combustion units at institutional facilities that burn solid materials and do not recover heat in the combustion firebox, but do recover waste heat from the hot combustion gases following the combustion firebox, would not be covered by the boilers NESHAP. The EPA does not consider it appropriate to regulate such units as boilers.
3

3
These units are often referred to as incinerators with waste heat recovery units or incinerators with waste heat boilers.

Incineration units are designed to discard materials by burning them at high temperatures and leaving as little residue as possible. Incineration units do not have heat recovery in the combustion firebox, but they may be followed by waste heat recovery units. Unlike a boiler (which is specifically designed to recover the maximum amount of heat from a material's combustion), waste heat recovery units are designed to cool the exhaust gas stream from an incineration unit, and/or to recover, indirectly, the useful heat remaining in the exhaust gas. The presence of a waste heat recovery unit on the exhaust gas does not change the fact that the unit combusting the material is primarily an incineration unit. Thus, a combustion unit with no heat recovery in the combustion firebox is still considered an incineration unit (
i.e.
, used primarily to dispose of solid waste), whether the incineration unit is followed by a waste heat recovery unit or not. Such incineration units just happen to have an external device (the waste heat recovery unit) that is recovering some of the waste heat from the incineration unit's exhaust gas. Therefore, IWI units are those units that combust materials with only waste heat recovery (
i.e.
, no heat recovery in the combustion firebox) or no heat recovery.

9. Rural Institutional Waste Incinerators

As discussed above, the OSWI inventory information shows slightly over 350 IWI. These units are located at a variety of institutions and burn solid waste materials generated on site, such as paper, packaging, food waste, rubbish, and garbage. About three-quarters of these IWI appear to be located at primary and secondary schools although, as mentioned, EPA considers this a significant overestimate of the number of IWI. While many IWI appear to be located in areas one would consider suburban or urban, a number appear to be located in areas one might consider rural.

In suburban and urban areas, commercial waste collection/transport/disposal services are widely available and, as a result, IWI in such areas have readily available alternatives to incineration (
i.e.
, commercial waste collection/transport/disposal services). In many rural areas, however, such

services are often very limited and, in some cases, unavailable. Thus, EPA considers IWI located in rural areas (
i.e.
, rural IWI) a distinct class of OSWI due to the lack of readily available commercial waste collection/transport/disposal services.

Because of the limited availability or even lack of such services, the only alternative to incineration for a rural IWI may be to transport their waste to a suburban or urban area, where such services are available. This, of course, would significantly increase the costs and, as such, EPA believes rural IWI merit separate consideration.

Thus, EPA has assessed the increased costs for a rural IWI which may have no reasonable alternative to incineration other than to transport their waste to a suburban or urban area. Based on this assessment, EPA concludes that such costs become significant when transport distances exceed 50 miles.

As mentioned above, the class of rural IWI consist primarily of incinerators located at primary or secondary schools in rural communities. In such communities, the local tax base supporting the school system is limited. School budgets are often stretched to the breaking point and unable to provide more than the minimum and bare essentials. In such an environment, a significant increase in solid waste disposal costs would impose an additional economic burden, which EPA concludes is unreasonable. For this reason, EPA has decided to exclude rural IWI.

To achieve this end, EPA has defined a rural IWI as an IWI located more than 50 miles from the boundary of the nearest Metropolitan Statistical Area (MSA). The Office of Management and Budget identifies areas classified as MSA and these areas are considered by EPA as suburban or urban areas. Thus, defining a rural IWI as an IWI located more than 50 miles from the boundary of the nearest MSA serves the objective of identifying those IWI located in rural areas where commercial waste collection/transport/disposal services may not be readily available or available at all, as well as identifying the maximum reasonable transport distance for an IWI to transport their waste to areas where such services are readily available.

10. Air Curtain Incinerators

Air curtain technology covers a wide variety of combustion equipment designs. For example, all air curtain units contain a fan and ductwork necessary to develop the “air curtain.” However, some units are designed to carry out waste combustion within a partially enclosed firebox (e.g., floor and walls, but open on top), while other designs may not involve a “firebox,” per se. These other designs consist only of a fan and ductwork to provide the “air curtain,” but the combustion is carried out in an earthen trench. The former are referred to as “firebox” units, and the latter are referred to as “trench burners.” For the purposes of the proposed rules, EPA is defining “air curtain incinerators” to include both types of units; firebox units as well as trench burners. Since air curtain incinerators could potentially be used for long-term municipal or institutional waste disposal, it makes sense to regulate them as OSWI units subject to the emission limits, operating limits, and other requirements of the proposed rules. Therefore, air curtain incinerators that otherwise meet the definition of OSWI would be regulated as OSWI.

Note that, as required by CAA section 129(g)(1), the proposed rules contain separate opacity requirements for air curtain incinerators burning only yard waste, wood waste, and clean lumber, and those units would not have to meet emission limits for the other CAA section 129 pollutants or the associated monitoring, recordkeeping and recording requirements. Air curtain incinerators that burn institutional or municipal waste, however, would have to meet all requirements of the proposed rules. Since air pollution control devices are unavailable for air curtain incinerators, this has the net effect of precluding the use of air curtain incinerators for burning municipal solid waste or institutional waste.

11. Incinerators and Air Curtain Incinerators in Isolated Areas of Alaska

There are locations in Alaska where limited options exist for solid waste disposal. These areas face unique situations that are not encountered elsewhere in the United States, and incinerators located in these areas merit special consideration. These are sparsely populated areas where access to a large MSW landfill or any other solid waste disposal option outside of the community is not available for all or part of a year. Within these areas, there are many isolated villages with small populations that have no road access. The only surface transportation in and out of many of these communities is barge traffic during the summer months. Other areas have roads that are not passable for much of the winter due to snow. In other cases, roads can be used in the winter when the rivers or streams that the road must cross are frozen, but the road is not available in the summer when the top layer of permafrost melts, turning the road into a bog. Rivers and streams without bridges thaw and become impassable. In such situations, there is no practical means of transporting waste. As a result, local waste management is the only option available to these communities.

In addition to the unavailability of waste transportation options, climatic conditions can make effective local landfilling difficult or even technically infeasible. These areas experience extended subfreezing conditions for the duration of the winter. In the summer months, the top layer of permafrost melts, turning potential waste disposal areas into bogs. Operation of a conventional landfill is extremely difficult under both weather extremes. In addition, adequate landfill cover material is unavailable in many areas. If waste is simply placed outside in a dump with no or insufficient cover material, it can attract birds and wild animals (such as bears and foxes) that can threaten villagers or spread disease. Waste burning in these remote Alaskan locations has the added benefits of decontaminating the waste, making the waste less attractive to wild animals, reducing the problem of blowing litter, and minimizing the generation and impacts of leachate.

In some Alaskan villages, incineration is used in conjunction with landfilling. In these areas, land that is physically suitable for a landfill is extremely scarce, so waste volume reduction is important to the village to prolong the life of the landfill. Alaskan villages may utilize waste segregation and recycling programs to reduce waste streams, but burning the remaining waste is also important to further reduce the waste volume and prolong the useful life of the local landfill.

Under authority of the SWDA, Alaskan State codes define landfills serving small populations in isolated areas with no access to a regional waste management facility for 3 or more months per year as “Class II” or “Class III” depending on size and accessibility constraints. Disposal sites classified as Class II or III experience the solid waste disposal challenges outlined in the previous paragraphs and incineration is common at these facilities.

As the previous discussion details, the challenges to the use of environmentally sound waste management practices at these remote Alaskan communities make incineration an essential component to their waste management system. Any CAA section 129 regulation imposed on incineration units used at these Class II or Class III facilities in Alaska, however, would effectively preclude use of incinerators.

Even a minimal rule that did not require new air pollution controls would make the cost of incineration prohibitively expensive, because CAA section 129 rules must contain testing, permitting, monitoring, recordkeeping, and reporting requirements. These requirements would easily double or triple the cost of operating an incinerator. These small Alaskan villages would not have the economic resources to comply with a regulation and would likely cease operating incineration units in response to any regulation.

The potential implications of the cessation of incineration at these Class II and Class III facilities include the rapid exhaustion of available landfill capacity, increased transmission of disease, increased threats from wild animals, and an increase in open burning. Therefore, EPA considers it important to preserve incineration as a waste disposal option for Class II and III facilities in Alaska. The EPA's consideration of the solid waste disposal options available at Class II and III facilities in Alaska shows an adverse environmental result from any action that would preclude or build barriers to incineration within these areas.

For these reasons, EPA has decided to exclude incinerators and air curtain incinerators used at solid waste disposal sites in Alaska that are classified as Class II or Class III facilities.

12. Incinerators Located on Remote Islands

The EPA recognizes that certain islands, Guam, American Samoa, the Virgin islands, and the Commonwealth of the Northern Mariana Islands, may lack suitable alternative disposal methods and find the cost of having sources comply with the proposed rules prohibitive. The EPA is not proposing an exclusion or exemption for such sources, but draws the attention of these islands to CAA section 325, which permits EPA to grant an exemption from CAA section 129 requirements upon petition of the “Governor” of one of these islands. The EPA would respond favorably and promptly to any such properly supported petition.

13. Temporary-Use Incinerators Used in Disaster or Emergency Recovery Efforts

The EPA realizes that in certain catastrophic situations, an incinerator may be a very useful tool in the recovery process. Clean-up and recovery efforts after disasters such as floods, tornados, or hurricanes are examples of situations where an incinerator may be useful. In these situations, quick removal of debris is of utmost importance to maintain public health and safety. Likewise, bioterrorist activities may warrant the immediate destruction of contaminated materials, in which case an incinerator may be best suited to perform the task. In these situations, the incinerator is used at a site only long enough to complete the recovery tasks, and is not used as a long-term waste disposal device. Accordingly, EPA considers that regulations imposed on incinerators temporarily used to recover from an emergency or disaster could perhaps hinder the recovery efforts, and this impact would outweigh any benefits possible under regulation of the units. To address this, EPA has included an exclusion for temporary-use incinerators used in disaster or emergency recovery efforts from regulation under OSWI.

This exclusion applies to temporary-use incinerators used in recovery efforts at local, State and Federally-declared disasters or emergencies. If the incinerator is used for recovery efforts in an area declared by the State as a State of Emergency, or that the President has declared, under the authority of the Stafford Act, a major disaster or emergency, then it would be excluded from regulation under OSWI for as long as required by the recovery effort. However, if the disaster or emergency has not been declared a State of Emergency or a major disaster or emergency, then the exclusion would apply to temporary-use incinerators used in recovery efforts at one location for 8 weeks or less. If the disaster recovery efforts are expected to take longer, the owner/operator of the unit would be required to submit a notification to the Administrator requesting approval to continue operating for a longer period of time. The incinerator may then be used for an additional 8 weeks at the same location while the Administrator reviews the request. After that time period the incinerator must cease operations or comply with the proposed rules unless the Administrator approves the request to operate at the location for a longer period of time.

14. Units that Combust Contraband or Prohibited Goods

The EPA realizes that government agencies sometimes must resort to incineration to destroy illegal drugs and items that are prohibited in all or portions of the U.S. due to biosecurity reasons. For example, few options other than incineration exist for the destruction or disposal of marijuana and other drugs seized by the police. Landfill disposal is not adequate due to the risk of someone recovering the contraband after authorities have attempted to dispose of it. As another example, produce seized by customs agents at points of entry into the United States may be infected by pathogens or pests that could severely threaten the domestic agriculture industry. In these cases, complete destruction via incineration may be the preferred method of disposal of the contaminated produce.

In such situations, EPA does not want to hinder or deter the use of incinerators by the government agency if it is necessary to protect public health and safety. Therefore, EPA has chosen to exclude units operated by government agencies that combust only contraband or prohibited goods from the proposed rules. Note that if contraband or prohibited goods are combusted with other waste in a VSMWC unit or IWI unit, the unit would be covered by the proposed rules.

15. Units That Combust Municipal Waste or Institutional Waste With Other Materials

In the discussion above, EPA has assumed that units within a potential subcategory are burning only the material described (
e.g.
, MSW, wood residue, contraband, etc.). As EPA has discussed, units at institutions burning institutional waste generated at that institution (IWI units) and VSMWC units would be subject to the emission limits and other requirements of the proposed rules. Any VSMWC or IWI unit that is also combusting other materials, such as contraband, agricultural residue, etc., described in this section of this preamble would be subject to the emission limits and other requirements of the proposed rules. For example, a VSMWC unit that is burning contraband along with municipal waste would be regulated under OSWI and would not qualify for the exclusion for units burning contraband. An incinerator that is burning only contraband would be excluded from the proposed rules. Similarly, an incineration unit that originally is excluded from regulation under OSWI, but subsequently burns municipal waste or institutional waste, would be subject to the emission limits and other requirements of the proposed rules.

B. How Did EPA Select the Pollutants to be Regulated?

The EPA selected emission limits for nine pollutants, as well as an opacity standard, for the proposed rules. As required by CAA section 129, the proposed rules would establish numerical emission limits for Cd, CO, dioxins/furans, HCl, Pb, Hg, opacity, NO
X
, PM, and SO
2
.

Section 129 of the CAA authorizes, but does not require, EPA to set limits for additional pollutants. The EPA has concluded that emission limits for additional pollutants are not needed because the emission limits for the nine listed pollutants ensure control of the other pollutants emitted by OSWI units. This decision is consistent with other CAA section 129 NSPS and emission guidelines (those for MWC units, HMIWI units, and CISWI units). The pollutants emitted by OSWI units fall into three general classes: Metals, organics, and acid gases. The limits for the nine pollutants, in conjunction with the combustor and control device operating parameter limits established by the regulations, would result in good control of all three classes of pollutants.

The emission limits for PM, Cd, and Pb ensure that emissions of all non-volatile metals are controlled. Cadmium, Pb, and other non-volatile metals are emitted as PM, and are removed by the same control devices that control PM emissions. The Cd, Pb, and PM limits would ensure that a wet scrubber or other control device is installed and operated in a manner that reduces emissions of all non-volatile metals. Mercury is the most volatile of the metals found in emissions from waste combustion units. If emission control devices meet the Hg limits, they would also be controlling any other volatile metals that may be present. Setting emission limits for additional metals would increase testing costs without obtaining any additional emissions reductions.

The emission limits for CO and dioxins/furans ensure control of organic pollutant emissions. Carbon monoxide concentration is a good indicator of combustion efficiency and the destruction of organic compounds. Complete combustion, as indicated by low CO emission limits, results in low emissions of organic compounds. High levels of CO indicate poor combustion conditions that are likely to result in high levels of organic compound emissions. The combustion techniques employed to minimize CO emissions are the same as those that are used to minimize organic compound emissions. Therefore, the CO emission limit would ensure that organic compound emissions are reduced.

Combustor load is also related to organic compound emissions. At loads above 100 percent, PM carryover could increase, and incinerator residence times could decrease, contributing to increased emissions of organic compounds including dioxins/furans. The proposed rules include a maximum charge rate operating limit, which would help achieve good control of organic pollutants. Dioxins/furans are a type of organic pollutant that is of particular health concern, and they can form on fly ash in the presence of oxygen at temperatures in the range of 250° to 400 °C (480° to 750 °F). Rapid flue gas cooling, for example by a wet scrubber, avoids dioxins/furans formation by this method. The specific emission limits for dioxins/furans would ensure that dioxins/furans emissions are minimized and, along with the CO and operating limits, would also result in the incinerators and control devices being designed and operated in a way that reduces emissions of other organic pollutants.

The emission limits for SO
2
and HCl would result in control of acid gases. Sulfur dioxide and HCl constitute the majority of acid gas emissions from waste combustion units. The same control technologies that reduce emissions of SO
2
and HCl, such as wet scrubbing, also remove emissions of any other acid gases. The SO
2
and HCl emission limits would ensure that the devices that control these two pollutants and other acid gases are installed and operated in a manner that reduces emissions.

The proposed rules require continuous monitoring of selected operating parameters to ensure that the control devices are continuously operated in the manner intended and result in continuous emissions reductions of PM and metals, organic pollutants, and acid gases. In summary, emission limits for other pollutants are not necessary because the emission limits for the nine pollutants would result in control of the other pollutants emitted by OSWI units.

C. How Did EPA Select the Format for the Proposed Rules?

The EPA selected an outlet concentration format for each pollutant because outlet data are available for combustion units using the control technologies that are the basis of the MACT emission limits. All concentration limits are corrected to 7 percent oxygen to provide a common basis. Opacity requirements are proposed on a percentage basis. The individual limits for each pollutant reflect the achievable performance of units using the MACT controls. The units of measure for each of the pollutants are consistent with other CAA section 129 rules and with the available data.

For regulating Cd, Pb, and Hg, the proposed numerical concentration limits are in units of μg/dscm. For total PM, the proposed concentration limits are in units of gr/dscf. Dioxins/furans emission limits are in units of total ng/dscm (total mass basis), based on measuring emissions of each tetra-through octa-chlorinated dibenzo-p-dioxin and dibenzofuran and summing them. For CO, HC1, NO
X
, and SO
2
, the proposed rules are volume concentrations (ppmdv).

In addition to numerical emission limits, the proposed rules include siting requirements (for new sources only) and operator training and qualification provisions as required by CAA section 129. Owners or operators of OSWI units would also be required to prepare a waste management plan.

D. How Did EPA Determine the Proposed Emission Limits for New OSWI Units?

All standards established pursuant to CAA section 129 must reflect MACT, the maximum degree of reduction in emissions of air pollutants that the Administrator, taking into consideration the cost of achieving such emission reduction, and any non-air quality health and environmental impacts and energy requirements, determines is achievable for each category. The CAA also specifies that the degree of reduction in emissions that is deemed achievable for new OSWI units must be at least as stringent as the emissions control that is achieved in practice by the best-controlled similar unit. This requirement constitutes the MACT “floor” for new OSWI units and EPA may not consider costs or other impacts in determining the MACT floor. The EPA may require a greater degree of reduction in emissions that is more stringent than the MACT floor (beyond-the-floor) if the Administrator considers the cost, environmental, and energy impacts to be reasonable.

Section 129(c) of the CAA specifies that standards “shall be based on methods and technologies for removal or destruction of pollutants before, during, or after combustion.” In determining the MACT floors and MACT, EPA considered source reduction and materials separation as potential methods of reducing pollutants before combustion. The EPA determined that the variable and heterogeneous nature of municipal solid waste and the site-specific and diverse nature of institutional waste make reliable quantification of emissions reductions associated with removal of various materials technically infeasible for the OSWI unit population. Each OSWI unit combusts a unique mixture of materials and, therefore, a single materials separation approach would not suffice for all OSWI units. Instead,

the EPA would require a site-specific waste management plan for each OSWI unit that identifies the feasibility and methods to reduce or separate components of solid waste from the waste stream to reduce toxic emissions from incineration of waste, as discussed later in this preamble.

In developing the MACT floors and MACT, EPA also considered methods for destruction of pollutants during combustion. The MACT floors and MACT are based on emission data for well-designed and well-operated combustion units, and the CO emission limits would assure proper operation of the combustor, which minimizes emissions of organic pollutants. Technologies for control of pollutants after combustion were also considered as described in the following discussions of the VSMWC and IWI unit MACT floors and beyond-the-floor alternatives.

For the proposed rules, we determined the new source MACT floors and MACT separately for the two subcategories of OSWI—the VSMWC subcategory and the IWI subcategory. Because there are similarities in unit size, design, and operation between the two subcategories, we request public comment on whether we should combine the two subcategories and determine a single new source MACT floor and a single set of new source MACT emission limits for the OSWI category as a whole. If the subcategories were combined, then we would use any available data for OSWI units (regardless of whether they are VSMWC or IWI units) to determine the MACT floor and MACT for the OSWI category.

1. How Did EPA Determine the MACT Floor for New OSWI Units?

To determine the MACT floor for new OSWI units, EPA must identify the “best performing similar unit, as determined by the Administrator.” The best performing “similar source” need not be in the category or subcategory subject to the MACT standard at issue. Rather, the source must be one that EPA, based on our evaluation of similarities and differences (
e.g.
, size, design, method of operation, purpose) has determined is sufficiently similar for us to base our regulations on. While EPA does not have emission test data for the units in the OSWI inventory, emissions information is available for other incineration units that EPA has concluded are “similar.” Accordingly, emission levels for the MACT floor level of control were determined by using actual emissions test data from similar units in other source categories.

New VSMWC MACT floor. The inventory of VSMWC units contains 14 units. All of the units for which MACT compliance control information is available report that they are “afterburner/uncontrolled” units (
i.e.
, two-chamber units consisting of a primary combustion chamber and an afterburner chamber, but no add-on control devices). However, all two-chamber incineration units use an “afterburner” in the second combustion chamber to ensure complete combustion burn-out. Thus, the use of an afterburner in the second combustion chamber is an integral part of the design and operation of these incinerators and does not represent an additional level of emission control beyond that which is inherent in the basic design and operation of VSMWC units. As a result, for the purposes of assessing the performance of these incineration units, EPA considers them “uncontrolled.”

While all of the sources in the VSMWC subcategory are uncontrolled, EPA has data on emissions and controls for HMIWI units that are similar to VSMWC units in size, design, and operation. Based on EPA's review of this information, EPA has determined that the most representative similar source would be an HMIWI unit using a “medium efficiency” wet scrubber. Small and medium sized HMIWI units, which are similar in size and design to VSMWC units, have low or medium efficiency wet scrubbers as required by the HMIWI rules. Furthermore, there is one OSWI unit, an IWI unit, with a medium efficiency wet scrubber.

While EPA has no emissions data for the IWI unit, EPA has reviewed compliance test data for HMIWI units, which includes the type of units that EPA has determined constitute the best performing similar source. Using this data, EPA determined the performance level of a “medium efficiency” wet scrubber by calculating the average emissions rate for all of the wet scrubbers on HMIWI units. Table 3 of this preamble shows the emission limits associated with the MACT floor for new VSMWC units.

Table 3.—New VSMWC MACT Floor Emission Limits

Pollutant

(concentration units @ 7% O
2
)

Emission
limit

PM (gr/dscf)
0.013

HCl (ppmdv)
3.7

SO
2
(ppmdv)

3.1

CO (ppmdv)
5.0

NO
X
(ppmdv)

103

Dioxins/Furans, Total Mass Basis (ng/dscm)
33

Hg (μg/dscm)
74

Cd (μg/dscm)
18

Pb (μg/dscm)
226

New IWI MACT floor. The IWI inventory contains 358 units. These units are two-chamber incineration units with an afterburner in the second chamber. Of these, there is one unit controlled with a medium efficiency wet scrubber.s

While EPA has no emissions data on IWI units, EPA has data for HMIWI units that are similar to IWI units in size, design, and operation. Based on EPA's review of this information, EPA has determined that the most representative similar source would be an HMIWI unit using a “medium efficiency” wet scrubber. Small and medium sized HMIWI units, which are similar in size and design to IWI units, have low or medium efficiency wet scrubbers as required by the HMIWI rules. The EPA reviewed compliance test data for HMIWI units, which includes the type of units that EPA has determined constitute the best performing similar source. Using this data, EPA determined the performance level of a “medium efficiency” wet scrubber by calculating the average emissions rate for all of the wet scrubbers on HMIWI units. Table 4 of this preamble shows the emission limits associated with the MACT floor for new IWI units.

Table 4.—New IWI MACT Floor Emission Limits

Pollutant

(concentration units @ 7% O
2
)

Emission
limit

PM (gr/dscf)
0.013

HCl (ppmdv)
3.7

SO
2
(ppmdv)

3.1

CO (ppmdv)
5.0

NO
X
(ppmdv)

103

Dioxins/Furans, Total Mass Basis (ng/dscm)
33

Hg (μg/dscm)
74

Cd (μg/dscm)
18

Pb (μg/dscm)
226

2. How Did EPA Determine Whether Options More Stringent Than the MACT Floor Were Appropriate for New OSWI Units?

In determining MACT, CAA section 129 directs EPA to “* * * require the maximum degree of reduction in emissions * * * that the Administrator, taking into consideration the cost of achieving such emission reduction and any non-air quality health and

environmental impacts and energy requirements, determines is achievable. * * *” However, MACT standards may be more stringent than the MACT floor.

The MACT floors for both the new VSMWC subcategory and the new IWI subcategory of OSWI are based on similar units with wet scrubbers, as described earlier in this preamble. The EPA did not identify any feasible regulatory options more stringent than the MACT floors for new VSMWC and IWI units. The EPA considered the possibility of dry sorbent injection systems with carbon injection and fabric filters, but available information indicated that the emissions reductions would be similar to wet scrubbing, and the costs to install and operate the controls would likely be much greater. Furthermore, analyses conducted for other CAA section 129 rules (
e.g.
, HMIWI) for incineration units of the same size and design have found that wet scrubbers are generally the emission control systems selected for very small incineration units.

The EPA does not expect any new VSMWC or IWI units to be built. However, a model plant analysis indicates that total emissions reductions for the nine regulated pollutants that would be achieved by requiring the floor level of control for a new VSMWC unit would range from 2.3 tpy to 67 tpy, depending on the model size and hours of operation. For a new IWI unit, the emissions reductions would range from 2.3 to 34 tpy, depending on the model size and hours of operation. The lower end of each range is based on a model batch unit with the capacity to burn 1 tpd of waste. The upper end of each range is based on an intermittently operated model unit with the capacity to burn 30 tpd for VSMWC units and 15 tpd for IWI units. The size ranges included in the model plant analysis represent the size ranges of units in each subcategory.

Because CAA section 129 requires EPA to establish regulations that are no less stringent than the MACT floor, EPA must require the MACT floor level of control for new VSMWC units and new IWI units regardless of cost. However, model plant cost analyses were conducted for informational purposes. The analyses showed that it is typically less expensive to send waste to a landfill than it is to construct and operate a new VSMWC unit or a new IWI unit. Available information indicates that no new VSMWC or IWI units are being built. The cost impacts of the MACT floor level of control are expected to be minimal, because municipalities and institutions would choose not to construct and operate new VSMWC or IWI units and would select an alternative waste disposal method.

Given that the MACT floors for both the new VSMWC subcategory and the new IWI subcategory of OSWI are based on wet scrubbers, the floor level of control achieves significant emissions reductions, and EPA has not identified any feasible beyond-the-floor alternatives that would achieve greater emissions reductions, EPA has chosen to base the NSPS for both the new VSMWC subcategory and the new IWI subcategory of OSWI on the use of wet scrubbers. The associated emission limits are shown in Tables 3 and 4 of this preamble.

E. How Did EPA Determine the Proposed Emission Limits for Existing OSWI Units?

All standards established pursuant to CAA section 129 must reflect MACT, the maximum degree of reduction in emissions of air pollutants that the Administrator, taking into consideration the cost of achieving such emission reduction, and any non-air quality health and environmental impacts and energy requirements, determines is achievable for each category. The CAA also specifies that the degree of reduction in emissions that is deemed achievable for existing units must not be less stringent than the average emissions limitation achieved by the best performing 12 percent of units in the category. This requirement constitutes the MACT “floor” for existing OSWI units. However, EPA may not consider costs or other impacts in determining the MACT floor. The EPA may require a greater degree of reduction in emissions that is more stringent than the MACT floor (beyond-the-floor) if the Administrator considers the cost, environmental, and energy impacts to be reasonable.

As with new units, EPA considered methods and technologies for removal or destruction of pollutants before combustion. For the same reasons described for new OSWI units, EPA concluded that the MACT floor for existing OSWI units does not include specific source reduction or materials separation requirements. Instead, EPA would require a site-specific waste management plan for each OSWI unit that identifies the feasibility and methods to reduce or separate components of solid waste from the waste stream to reduce toxic emissions from incinerated waste. Waste management plan requirements are discussed in more detail later in this preamble.

In developing the MACT floors and MACT, EPA also considered methods for destruction of pollutants during combustion. The MACT floors and MACT are based on emissions data for well-designed and well-operated combustion units, and the CO emission limits would assure proper operation of the combustor, which minimizes emissions of organic pollutants. Technologies for control of pollutants after combustion were also considered as described in the following discussions of the VSMWC and IWI unit MACT floors and beyond-the-floor alternatives.

For the proposed rules, we determined the existing source MACT floors and MACT separately for two subcategories of OSWI—the VSMWC subcategory and the IWI subcategory. Because there are similarities in unit size, design, and operation between the two subcategories, we request public comment on whether we should combine the two subcategories and determine a single existing source MACT floor and a single set of existing source MACT emission limits for the OSWI category as a whole. If the subcategories were combined, then we would use any available data for OSWI units (regardless of whether they are VSMWC or IWI units) to determine the MACT floor and MACT for the OSWI category.

1. How Did EPA Determine the MACT Floor for Existing OSWI Units?

To determine the MACT floor for existing OSWI units EPA must identify the “best performing units” in the category or subcategory. The EPA does not have emissions test data for the units in the OSWI inventory. However, the inventory contains information on air pollution control devices installed on the units. Therefore, information on control devices was used to identify the best performing units in the VSMWC and IWI subcategories and establish the control technology basis of the MACT floors for each. The EPA then determined emissions levels achieved by the MACT floor level of control by using actual emissions test data from similarly controlled incineration units in other source categories, because of the lack of OSWI emissions test data.

Existing VSMWC MACT floor. The inventory of VSMWC units contains 14 units. All of the units for which MACT compliance control information is available report that they are “afterburner/uncontrolled” units (
i.e.
, two-chamber units consisting of a primary combustion chamber and an afterburner chamber, but no add-on control devices). However, all conventional two-chamber incineration units use an “afterburner” in the second

combustion chamber to ensure complete combustion burn-out. Thus, the use of an afterburner in the second combustion chamber is an integral part of the design and operation of these incinerators and does not represent an additional level of emission control beyond that which is inherent in the basic design and operation of VSMWC units. As a result, for the purposes of assessing the performance of these incineration units, EPA considers them “uncontrolled.” For existing VSMWC units, 12 percent of 14 units is two units. Therefore, the average of the best performing two units, or existing source MACT floor, is based on the emission limits achievable by a well-operated, uncontrolled (
i.e.
, afterburner), two-chamber incinerator.

Because there were not any emissions test data available for the actual OSWI units in our inventory, EPA looked to similar source categories for test data. The EPA found test data for small uncontrolled, modular/starved air MWC units that were collected during the MWC regulatory development process. These units are two-chamber units that are the same in design and waste burned as the units within the OSWI category. Therefore, these data were used to establish the MACT floor emission limits. Table 5 of this preamble shows the emission limits associated with the MACT floor for existing VSMWC units.

Table 5.—Existing VSMWC and IWI MACT Floor Emission Limits

Pollutant

(concentration units @ 7% O
2
)

Emission limit

PM (gr/dscf)
0.1

HCl (ppmdv)
500

SO
2
(ppmdv)

200

CO (ppmdv)
50

NO
X
(ppmdv)

215

Dioxins/Furans, Total Mass Basis (ng/dscm)
300

Hg (μg/dscm)
500

Cd (μg/dscm)
310

Pb (μg/dscm)
4,300

Existing IWI MACT floor. The IWI inventory contains 358 units. Of these, there is one unit controlled with a medium efficiency wet scrubber. The rest of the IWI units are “afterburner/uncontrolled” units (see VSMWC discussion above). Twelve percent of 358 units is 43 units. Therefore, the average of the best performing 12 percent, or MACT floor, is based on the emission limits achievable by a well-operated, uncontrolled, two-chamber incinerator. Because there were not any emissions test data available for the actual OSWI units in our inventory, EPA looked to similar source categories for test data. The EPA found test data for small uncontrolled, modular/starved air MWC units that were collected during the MWC regulatory development process. These units are two-chamber units that are the same in design and waste burned as the units within the OSWI category. Therefore, these data were used to establish the emission limits for uncontrolled units. Table 5 of this preamble shows the emission limits associated with the MACT floor for existing IWI units.

2. How Did EPA Determine Whether Options More Stringent Than the MACT Floor Were Appropriate for Existing OSWI Units?

In determining MACT, CAA section 129 directs EPA to “* * * require the maximum degree of reduction in emissions * * * that the Administrator, taking into consideration the cost of achieving such emission reduction and any non-air quality health and environmental impacts and energy requirements, determines is achievable. * * *” The MACT standards may be more stringent than the MACT floor. The MACT floors for both the existing VSMWC subcategory and the existing IWI subcategory of OSWI are based on the emission limits achievable by a well-operated, uncontrolled, two-chamber unit. For existing VSMWC and IWI units, EPA identified one regulatory option beyond the floor: Emission limits based on the use of a wet scrubber. One OSWI unit (an IWI unit) currently uses a wet scrubber, and this control technology could be applied to both IWI and VSMWC units and would substantially reduce emissions. After considering the emission reduction benefits, costs, and other impacts, EPA has decided to base the emission guidelines for the existing VSMWC subcategory and for the existing IWI subcategory of OSWI on the emission limits achievable through the use of a wet scrubber. These emission limits are significantly more stringent than the MACT floors for these subcategories. The EPA expects that the cost impacts of the emission guidelines for existing VSMWC and IWI units would be minimal for reasons described below.

Table 6 of this preamble shows the emission levels associated with the MACT floor for existing VSMWC and IWI units and the wet scrubber beyond-the-floor regulatory option. These emission levels were established from the data described earlier in this preamble. Because the MACT floors for existing VSMWC and IWI are based on units without controls, the emission reduction that would be achieved by requiring existing VSMWC and IWI units to meet the MACT floor is negligible. In contrast, the total emissions reductions for the nine regulated pollutants that would be achieved by requiring any existing units to meet the beyond-the-floor option would range from 2.3 tpy to 67 tpy for a VSMWC model unit and from 2.3 to 34 tpy for an IWI model unit, depending on the unit's capacity and hours of operation. The lower end of each range is based on a model batch unit with a capacity of 1 tpd, and the upper end is based on an intermittently operated model unit with a capacity of 30 tpd for VSMWC units and 15 tpd for IWI units. These represent the size ranges of existing units in each subcategory.

Table 6.—Emission Levels for MACT Floor and Beyond-the-Floor Regulatory Options for the Existing VSMWC and IWI Subcategories of OSWI

Pollutant

(concentration units @ 7% O
2
)

MACT
floor
emission
limit

Emission
limit
based on wet
scrubber

PM (gr/dscf)
0.1
0.013

HCl (ppmdv)
500
3.7

SO
2
(ppmdv)

200
3.1

CO (ppmdv)
50
5.0

NO
X
(ppmdv)

215
103

Dioxins/Furans, Total Mass Basis (ng/dscm)
300
33

Hg (μg/dscm)
500
74

Cd (μg/dscm)
310
18

Pb (μg/dscm)
4,300
226

In comparing the cost impacts of the floor and the beyond-the-floor regulatory option, the cost impacts of both options are estimated to be minimal because facilities would elect to use a lower-cost alternative waste disposal method. The EPA analyzed the compliance costs for model existing VSMWC and IWI units for the floor regulatory option, the wet scrubbing regulatory option, and an alternative waste disposal method. The analysis indicates that, even though the floor option is based on units with no control, the cost of meeting emission guidelines based on the MACT floor would be significant, and municipalities and institutions would likely choose to shut down existing VSMWC or IWI units and would instead use alternative waste disposal options such as landfilling or sending their waste to a regional MWC unit that is already subject to the small or large MWC regulations.

The costs of complying with emission guidelines based on the MACT floor would be significant because all emission guidelines developed under

CAA section 129 must include operator training and qualification requirements as well as testing, permitting, monitoring, and reporting requirements. State and Federal plans developed to implement the emission guidelines must also contain these requirements. Even if an existing VSMWC or IWI unit did not need to install air pollution controls to meet the MACT floor emission levels, EPA estimates significant costs to meet all of these other requirements. For example, EPA estimates that operator training, testing, permitting, monitoring, recordkeeping, and reporting costs to comply with the MACT floor option would be over $116,000 per year for an existing VSMWC or IWI unit. This cost is significantly more than the annual cost of operating most VSMWC and IWI units. In fact, it could double, triple, or quadruple the annual costs of an existing VSMWC or IWI unit, depending on its size. The EPA estimates the annual costs of installing and operating a wet scrubber and meeting the training, testing, permitting, monitoring, recordkeeping, and reporting requirements of the emission guidelines would range from $162,000 to $253,000 per year for existing VSMWC units and from $162,000 to $207,000 for existing IWI units, depending on the unit's size and operating schedule. Therefore, the likely response to the emission guidelines (regardless of whether it is based on the floor or the beyond-the-floor option) would be for municipalities and institutions to examine and select alternative waste disposal options.

Information available on the response by existing sources to other CAA section 129 rulemakings indicates that many sources chose to close and rely on alternatives to incineration in managing their solid waste, rather than incur the costs of compliance with the regulation. The EPA anticipates a similar response would appeal to sources subject to OSWI emission guidelines. The model plant analysis indicates that, even in the absence of the emission guidelines, it typically would be less expensive to shut down an incinerator and send waste to a landfill than it would be to continue operating an existing VSMWC or IWI unit. The general findings of this analysis are reinforced by the trend of closure of many units over the past several years. However, EPA realizes that many site-specific factors influence both the cost of operating a specific existing waste combustion unit and the cost of sending the waste to a landfill or other alternative disposal method, and therefore, some facilities may experience a small increase over their current costs by switching to an alternative disposal method. Given the widespread availability of waste disposal alternatives such as landfilling, the trend toward closure of VSMWC and IWI units, the results of the model plant cost analysis, and the response of sources to other CAA section 129 regulations, EPA expects that the cost impacts of the beyond-the-floor option for existing VSMWC and IWI units would be minimal because most municipalities and institutions would choose to shut down their existing VSMWC and IWI units and would select an alternative waste disposal method. Use of an alternative disposal method would result in a negligible increase in costs, and may even result in cost savings for some units.

While EPA's objective is to adopt MACT emission guidelines that fulfill the requirements of CAA section 129 and not to cause the shutdown of most existing VSMWC and IWI units, EPA considers the replacement of poorly controlled incinerators with cost effective alternative disposal techniques that significantly reduce toxic emissions as an appropriate outcome. From a national perspective, emission guidelines for existing VSMWC and IWI units based on the use of wet scrubbing (and the switching to alternative waste disposal options that would result) would minimize emissions of PM, dioxin, acid gases, and metals from VSMWC and IWI units at a relatively low cost, due to the availability of alternative means of waste disposal. As a result, the proposed emission guidelines for both subcategories of OSWI are based on emission limits achievable through the use of wet scrubbers. These emission limits are substantially more stringent than the MACT floors for existing VSMWC and IWI units.

F. How did EPA Determine Testing and Monitoring Requirements for the Proposed Rules?

The EPA determined testing and monitoring requirements for the proposed rules that are consistent with the CAA. Section 129(c) of the CAA requires EPA to develop regulations that include monitoring and testing requirements. The purpose of these requirements is to allow EPA to determine whether a source is operating in compliance with the proposed rules. The proposed monitoring and testing requirements are discussed below.

1. Continuous Emission Monitoring Systems

The most direct means of ensuring compliance with emission limits is the use of continuous emission monitoring systems (CEMS). As a matter of policy, the first and foremost option considered by EPA is to require the use of CEMS to demonstrate continuous compliance with specific emission limits. The EPA considers other options only when CEMS are not available or when the impacts of including such requirements are considered unreasonable.

Continuous emissions monitoring of CO is feasible and is proposed to determine compliance with the CO emission limit and to indicate proper operation of the combustion unit. Monitoring emissions of CO on a continuous basis is the most effective way to ensure that the combustion unit is operating properly. Low CO emissions indicate good combustion, which, in turn, ensures destruction of other pollutants such as organics. In addition, good combustion helps to keep PM emissions lower.

Compliance with the CO emission limit would be determined on a 3-hour rolling average basis using CEMS data. The EPA would require CEMS for CO to ensure proper combustion performance. Data provided by CO CEMS assures EPA and the public that the combustion unit is operating properly.

Continuous emission monitors are not readily available for many of the other pollutants regulated under the proposed rules. For example, CEMS for metals and dioxins/furans are either very expensive or are still being developed. Thus, the proposed rules require monitoring of operating parameters to ensure proper operation of the air pollution control devices.

Although monitoring of operating parameters cannot provide a direct measurement of emissions, it is often a suitable substitute for CEMS. The information provided can be used to ensure that the air pollution control equipment is operating properly. This information reasonably assures EPA and the public that the reductions in acid gases, organic pollutants, metals, and PM envisioned by the regulations are being achieved. The proposed rules include requirements for initial and annual stack testing using EPA methods, coupled with monitoring of operating parameters. The owner or operator of each OSWI unit would use the initial stack test to calibrate the monitoring parameters.

Parameter monitoring is proposed to indicate proper operation of the wet scrubber. Parameter monitoring is

proposed on a rolling 3-hour basis to correspond to the approximate length of the required emission tests. The EPA sel

[Text truncated at 120,000 characters. The full text is on the page linked above.]

---

Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A04-26741. Public record. Not legal advice.