6560-50-P

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 60 and 241

[EPA–HQ–OAR–2003-0119 and EPA-HQ-RCRA 2008-0329; FRL- ]

RIN 2060-AR15 and 2050-AG44

Commercial and Industrial Solid Waste Incineration Units: 

Reconsideration and Final Amendments; Non-Hazardous Secondary 

Materials That Are Solid Waste: Final Rule

AGENCY: Environmental Protection Agency.

ACTION: Final rule; notice of final action on reconsideration.

SUMMARY: This action sets forth the EPA’s final decision on the 

issues for which it granted reconsideration in December 2011, 

which pertain to certain aspects of the March 21, 2011, final 

rule titled “Standards of Performance for New Stationary Sources 

and Emissions Guidelines for Existing Sources: Commercial and 

Industrial Solid Waste Incineration Units” (CISWI rule). This 

action also includes our final decision to deny the requests for 

reconsideration with respect to all issues raised in the 

petitions for reconsideration of the final commercial and 

industrial solid waste incineration rule for which we did not 

grant reconsideration. Among other things, this final action 

establishes effective dates for the standards and makes 

technical corrections to the final rule to clarify definitions, 

references, applicability and compliance issues. In addition, 

the EPA is issuing final amendments to the regulations that were 
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codified by the Non-Hazardous Secondary Materials rule (NHSM 

rule). Originally promulgated on March 21, 2011, the nonhazardous secondary materials rule provides the standards and 

procedures for identifying whether non-hazardous secondary 

materials are solid waste under the Resource Conservation and 

Recovery Act when used as fuels or ingredients in combustion 

units. The purpose of these amendments is to clarify several 

provisions in order to implement the non-hazardous secondary 

materials rule as the agency originally intended.

DATES: The stay of effectiveness for 40 CFR part 60, subparts 

CCCC and DDDD is lifted and the incorporation by reference of 

certain publications listed in that rule are effective as of 

[INSERT THE DATE OF PUBLICATION OF THIS FINAL RULE IN THE 

FEDERAL REGISTER]. The amendments in this rule to 40 CFR part 

60, subpart DDDD, are effective as of [INSERT THE DATE OF 

PUBLICATION OF THIS FINAL RULE IN THE FEDERAL REGISTER] and to 

40 CFR part 60, subpart CCCC, are effective as of [INSERT THE 

DATE SIX MONTHS AFTER PUBLICATION OF THIS FINAL RULE IN THE 

FEDERAL REGISTER].

ADDRESSES: The EPA established a single docket under Docket ID 

Number EPA-HQ-OAR-2003-0119 for this action on the commercial 

and industrial solid waste incineration rule. The EPA also 

established a single docket under Docket ID Number EPA-HQ-RCRA2008-0329 for this action on the non-hazardous secondary 
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materials rule. All documents in the docket are listed in the 

http://www.regulations.gov index. Although listed in the index, 

some information is not publicly available, e.g., confidential 

business information or other information whose disclosure is 

restricted by statute. Certain other material, such as 

copyrighted material, will be publicly available only in hard 

copy. Publicly available docket materials are available either 

electronically in http://www.regulations.gov or in hard copy at 

the EPA Docket Center, EPA West Building, Room 3334, 1301 

Constitution Ave., NW, Washington, DC. The Public Reading Room 

is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, 

excluding legal holidays. The telephone number for the Public 

Reading Room is (202) 566-1744 and the telephone number for the 

Docket Center is (202) 566-1742.

FOR FURTHER INFORMATION CONTACT: For further information 

regarding the commercial and industrial solid waste incineration 

reconsideration and final rule, contact Ms. Toni Jones, Fuels 

and Incineration Group, Sector Policies and Programs Division

(E143–05), Environmental Protection Agency, Research Triangle 

Park, North Carolina 27711; telephone number: (919) 541–0316; 

fax number: (919) 541–3470; email address: jones.toni@epa.gov, 

or Ms. Amy Hambrick, Fuels and Incineration Group, Sector 

Policies and Programs Division (E143–05), Environmental 

Protection Agency, Research Triangle Park, North Carolina 27711; 
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telephone number: (919) 541–0964; fax number: (919) 541–3470; 

email address: hambrick.amy@epa.gov. 

For further information regarding the Non-Hazardous 

Secondary Materials final rule, contact Mr. George Faison, 

Program Implementation and Information Division, Office of 

Resource Conservation and Recovery, 5303P, Environmental 

Protection Agency, Ariel Rios Building, 1200 Pennsylvania 

Avenue, NW, Washington, DC 20460-0002; telephone number: 703-

305-7652; fax number: 703-308-0509; email address: 

faison.george@epa.gov.

I. Organization of this Document 

The following outline is provided to aid in locating 

information in this preamble. 

I. Organization of this Document

A. Supplementary Information

B. Does this action apply to me?

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

D. Judicial Review

E. Executive Summary

II. CISWI Reconsideration and Final Rule

A. Background Information

1. What is the history of the CISWI standards?

2. How is the definition of solid waste addressed in the final 

CISWI rule?

3. What is the relationship between this rule and other 

combustion rules?

4. What is the response to the vacatur of effective dates?

B. Summary of This Final Rule

1. Subcategories of Affected Units and Emission Standards

2. Fuel Switching Provisions

3. Definitions of Cyclonic Burn Barrels, Burn-off Ovens, Soil 

Treatment Units, Laboratory Analysis Units and Space Heaters

4. Affirmative Defense for Malfunction Events

5. Oxygen Correction Requirements and CO Monitoring Requirements
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6. Full-load Stack Test Requirement for CO Coupled With 

Continuous O2 Monitoring

7. Non-detect Methodology Using Three Times the Detection Level

8. Definitions for Foundry Sand Thermal Reclamation Unit and 

Chemical Recovery Unit

9. Definition of Contained Gaseous Material

10. Parametric Monitoring Provisions for Additional Control 

Device Types

11. Particulate Matter Continuous Monitoring Provisions for 

Large ERUs and Waste-burning Kilns

12. Revised Definition of Waste-burning Kiln

13. Revised Definition of Solid Waste

14. Compliance Dates

C. Summary of Significant Changes Since Proposal

1. Revision of the Subcategories

2. Revisions to the Monitoring Requirements

3. Oxygen Monitoring Requirements

4. Removal of the Definition of Homogeneous Waste

5. Non-detect Methodology Using Three Times the Detection Level

6. Parametric Monitoring for Additional Control Device Types

7. Particulate Matter Continuous Monitoring Provisions for Large 

ERUs and Waste-burning Kilns 

8. Compliance Dates

9. Definition of Waste-burning Kiln

10. Exemption for Other Solid Waste Incineration (OSWI) Units

D. Technical Corrections and Clarifications

E. Major Public Comments and Responses

F. What other actions are we taking?

G. What are the impacts associated with the amendments?

1. What are the primary air impacts?

2. What are the water and solid waste impacts?

3. What are the energy impacts?

4. What are the secondary air impacts?

5. What are the cost and economic impacts?

6. What are the benefits?

III. NHSM Final Revisions

A. Statutory Authority 

B. NHSM Rule History

C. Introduction – Summary of Regulations Being Finalized

1. Revised Definitions

a. Clean Cellulosic Biomass

b. Contaminants

c. Established Tire Collection Programs

d. Resinated Wood

2. Contaminant Legitimacy Criterion for NHSM Used as Fuels

3. Categorical Non-Waste Determinations for Specific NHSM Used 

as Fuels
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a. Scrap Tires

b. Resinated Wood

c. Coal Refuse

d. Pulp and Paper Sludge

4. Rulemaking Petition Process for Other Categorical Non-Waste 

Determinations (40 CFR 241.4(b))

5. Streamlining of the 40 CFR 241.3(c) Non-Waste Determination 

Petition Process

6. Revised Introductory Text for 40 CFR 241.3(a)

D. Comments on the Proposed Rule and Rationale for Final 

Decisions

1. Revised Definitions

a. Clean Cellulosic Biomass

b. Contaminants

c. Established Tire Collection Programs

2. Contaminant Legitimacy Criterion for NHSMs Used as Fuels

a. General Comments on the Revised Contaminant Legitimacy 

Criterion

b. Grouping of Contaminants

c. Meaning of Designed to Burn

d. Contaminant Comparisons Allowed

3. Categorical Non-Waste Determinations for Specific NHSM Used 

as Fuels

a. Scrap Tires

b. Resinated Wood

4. Rulemaking Petition Process for Other Categorical Non-Waste 

Determinations (40 CFR 241.4(b))

5. Materials for Which Additional Information was Requested 

a. Pulp and Paper Sludge

b. Coal Refuse 

c. Manure

d. Other Materials for Which Additional Information was Not 

Requested

6. Streamlining of the 40 CFR 241.3(c) Non-Waste Determination 

Petition Process

7. Revised Introductory Text for 40 CFR 241.3(a)

E. Cost and Benefits of the Final Rule 

IV. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and 

Executive Order 13563: Improving Regulation and Regulatory 

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
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G. Executive Order 13045: Protection of Children from 

Environmental Health Risks and Safety Risks

H. Executive Order 13211: Actions Concerning Regulations That 

Significantly Affect Energy Supply, Distribution, or Use

I. National Technology Transfer and Advancement Act

J. Executive Order 12898: Federal Actions to Address 

Environmental Justice in Minority Populations and Low-Income 

Populations

K. Congressional Review Act

A. SUPPLEMENTARY INFORMATION: 

Acronyms and Abbreviations. The following acronyms and 

abbreviations are used in this document. 

ACI activated carbon injection

AF&PA American Forest & Paper Association

ANPRM Advanced Notice of Proposed Rulemaking

ANSI American National Standards Institute

APA Administrative Procedure Act

ARIPPA Anthracite Region Independent Power 

Producers Association

ASME American Society of Mechanical Engineers 

AST activated sludge treatment

ASTM American Society for Testing and Materials

ATCM Air Toxic Control Measure

Btu British thermal unit

CAA Clean Air Act 

CARB California Air Resources Board 

CBI Confidential Business Information

CCA chromated copper arsenate 

Cd cadmium 

C&D construction & demolition

CDX Central Data Exchange

CFB circulating fluidized bed

CEMS continuous emissions monitoring systems 

CERCLA Comprehensive Environmental Response, Compensation, 

and Liability Act

CFR Code of Federal Regulations

CISWI Commercial and Industrial Solid Waste Incineration 

CO carbon monoxide 
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CO2 carbon dioxide

Catalyst carbon monoxide oxidation catalyst 

Cl2 chlorine gas

CPMS continuous parametric monitoring system

CWA Clean Water Act

D/F dioxin/furan

dscm dry standard cubic meter

DSW Definition of Solid Waste

EG emission guidelines 

EJ Environmental Justice 

EOM extractable organic matter 

EPA U.S. Environmental Protection Agency

ERT Electronic Reporting Tool

ERU energy recovery unit

ESP electrostatic precipitator 

FF fabric filters

FR Federal Register

HAP hazardous air pollutants

HCl hydrogen chloride 

HF hydrogen fluoride

Hg mercury 

HMI hospital, medical and infectious

HMIWI Hospital, Medical and Infectious Waste Incineration 

ICR Information Collection Request

Lb pound

LML lowest measured level

Mg milligram

Mn manganese

MACT maximum achievable control technology

MDL method detection level

mg/dscm milligrams per dry standard cubic meter

mmBtu/hr million British thermal units per hour

MSW Municipal Solid Waste

MW megawatts

MWC Municipal Waste Combustor 

NAAQS National Ambient Air Quality Standards

NAICS North American Industrial Classification System 

NCASI National Council on Air and Stream Improvement

ND nondetect
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NESHAP National Emission Standards for Hazardous Air 

Pollutants 

ng/dscm nanograms per dry standard cubic meter

NHSM non-hazardous secondary material(s)

NIST National Institute of Standards and Technology

NOx nitrogen oxides

NSPS New Source Performance Standards 

NTTAA National Technology Transfer and Advancement Act

OAQPS Office of Air Quality Planning and Standards

OMB Office of Management and Budget

OSWI Other Solid Waste Incineration

OSWER Office of Solid Waste and Emergency Response

O2 Oxygen

PAH polycyclic aromatic hydrocarbons 

Pb lead

PCBs polychlorinated biphenyls 

PCDD polychlorinated dibenzodioxins

PCDF polychlorinated dibenzofurans

PIC product of incomplete combustion

PM particulate matter

POM polycyclic organic matter 

ppm parts per million

ppmv parts per million by volume 

ppmvd parts per million by dry volume 

PQL practical quantitation limit

PRA Paper Reduction Act

PS Performance Specification

lb/MMBtu pound per million British thermal units

RCRA Resource Conservation and Recovery Act 

RDL reported detection level

RFA Regulatory Flexibility Act

RIA Regulatory Impact Analysis

RIN Regulatory Information Number 

RTO regenerative thermal oxidizer

RTR residual risk and technology review

SBA Small Business Administration

SBREFA Small Business Regulatory Enforcement Fairness Act

SISNOSE Significant Economic Impact on a Substantial Number

of Small Entities
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SMCRA Surface Mining Control and Reclamation Act of 1977

SNCR selective noncatalytic reduction 

SO2 sulfur dioxide

SSI Sewage Sludge Incineration

SSM startup, shutdown and malfunction

SVOC Semi-Volatile Organic Compound

SWDA Solid Waste Disposal Act

TBtu tera British thermal unit

TEOM Tapered Element Oscillating Microbalance

TEQ Toxic Equivalency

The Court U.S. Court of Appeals for the District of Columbia 

Circuit

TMB Total Mass Basis

TOX Total Organic Halogens 

tpy tons per year

TSM Total Selected Metal

TTN Technology Transfer Network 

UCL upper confidence limit

ug/dscm micrograms per dry standard cubic meter

UMRA Unfunded Mandates Reform Act

UL upper limit

UPL upper prediction limit

U.S.C. United States Code

USGS United States Geological Survey

VCS Voluntary Consensus Standards

VOC volatile organic compound

WWW Worldwide Web

B. Does this action apply to me?

Categories and entities potentially affected by this action 

are those that operate CISWI units and those that generate 

potentially affected NHSMs. The NSPS and EG, hereinafter 

referred to as “standards,” for CISWI affect the following 

categories of sources:

Category NAICS1

Code

Examples of Potentially

Regulated Entities
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Category NAICS1

Code

Examples of Potentially

Regulated Entities

Any industrial 

or commercial 

facility using 

a solid waste 

incinerator

211, 212, 

486

Oil and Gas Extraction, mining 

(except oil and gas); Pipeline 

Transportation 

221 Utilities

321, 322, 

337

Wood Product Manufacturing, Paper 

Manufacturing, Furniture and Related 

Product Manufacturing 

325, 326 Chemical Manufacturing, Plastics and 

Rubber Products Manufacturing

327 Nonmetallic Mineral Product 

Manufacturing, 

333, 336

Machinery Manufacturing, 

Transportation Equipment 

Manufacturing 

423, 44, Merchant Wholesalers, Durable Goods, 

Retail Trade

Any facility 

or entity 

generating a 

non hazardous 

secondary 

material that 

may be burned 

for fuel or 

destruction2

111 Crop Production

112 Animal Production

113 Forestry and Logging

115 Support Activities for Agriculture 

and Forestry

211 Oil and Gas Extraction

212 Mining (except oil and gas)

221 Utilities

236 Construction of Buildings

311 Food Manufacturing

312 Beverage and Tobacco Product 

Manufacturing

313 Textile Mills

316 Leather and Allied Product 

Manufacturing

321 Wood Product Manufacturing

322 Paper Manufacturing

324 Petroleum and Coal Products 

Manufacturing

325 Chemical Manufacturing

326 Plastics and Rubber Products 

Manufacturing

327 NonMetallic Mineral Product 

Manufacturing

331 Primary Metal Manufacturing
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Category NAICS1

Code

Examples of Potentially

Regulated Entities

332 Fabricated Metal Product 

Manufacturing

333 Machinery Manufacturing

334 Computer and Electronic Product 

Manufacturing

336 Transportation Equipment 

Manufacturing

337 Furniture and Related Product 

Manufacturing

339 Miscellaneous Manufacturing

423 Merchant Wholesalers, Durable Goods

424 Merchant Wholesalers, Nondurable 

Goods

44-45

Retail Trade (all categories, 

including non-store retailers, 

vending and direct sellers)

486 Pipeline Transportation

493 Warehousing and Storage

511 Publishing Industries (except 

internet)

531 Real Estate

541 Professional, Scientific and 

Technical Services

611 Educational Services

622 Hospitals

623 Nursing and Residential Care 

Facilities

624 Social Assistance

713930 Boating Clubs with Marinas

721 Accommodation 

722 Food Services and Drinking Places

813

Religious, Grantmaking, Civic, 

Professional and Similar 

Organizations 

92 Public Administration

1 North American Industry Classification System.

2 Note that some of these NAICS may overlap with institutional 

facility types where incinerators are regulated by the Other 

Solid Waste Incinerators (OSWI) emission guidelines and NSPS. 
Page 13 of 319

This table is not intended to be exhaustive but rather 

provides a guide for readers regarding entities likely to be 

affected by the final action. To determine whether your facility 

would be affected by the final action, you should examine the 

applicability criteria in 40 CFR 60.2010 of subpart CCCC, 40 CFR 

60.2505 of subpart DDDD, and 40 CFR 241. If you have any 

questions regarding the applicability of the final action to a 

particular entity, contact the persons listed in the preceding 

FOR FURTHER INFORMATION CONTACT section.

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

The docket number for the action regarding the CISWI NSPS 

(40 CFR part 60, subpart CCCC) and EG (40 CFR part 60, subpart 

DDDD) is Docket ID Number EPA–HQ–OAR–2003–0119.

Worldwide Web. In addition to being available in the 

docket, an electronic copy of the final action is available on 

the WWW through the TTN Web. Following signature, the EPA posted 

a copy of the final action 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.

D. Judicial Review

Under the CAA section 307(b)(1), judicial review of this 

final rule is available only by filing a petition for review in 

The Court [INSERT DATE 60 DAYS FROM DATE OF PUBLICATION OF THE 
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FINAL RULE IN THE FEDERAL REGISTER]. Under CAA section 

307(d)(7)(B), only an objection to this final rule that was 

raised with reasonable specificity during the period for public 

comment can be raised during judicial review. This section also 

provides a mechanism for us to convene a proceeding for 

reconsideration, "[i]f the person raising an objection can 

demonstrate to EPA that it was impracticable to raise such 

objection within [the period for public comment] or if the 

grounds for such objection arose after the period for public 

comment (but within the time specified for judicial review) and 

if such objection is of central relevance to the outcome of this 

rule." Any person seeking to make such a demonstration to us 

should submit a Petition for Reconsideration to the Office of 

the Administrator, Environmental Protection Agency, Room 3000, 

Ariel Rios Building, 1200 Pennsylvania Ave., NW., Washington, DC 

20004, with a copy to the persons listed in the preceding FOR 

FURTHER INFORMATION CONTACT section, and the Associate General 

Counsel for the Air and Radiation Law Office, Office of General 

Counsel (Mail Code 2344A), Environmental Protection Agency, 1200 

Pennsylvania Ave., NW., Washington, DC 20004. Note, under CAA 

section 307(b)(2), the requirements established by this final 

rule may not be challenged separately in any civil or criminal 

proceedings brought by the EPA to enforce these requirements. 
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Resource Conservation and Recovery Act sections of the rule 

would be subject to judicial review under RCRA.

E. EXECUTIVE SUMMARY:[A1]

Purpose of the Regulatory Action[A2]

The EPA is promulgating final rules that establish 

standards for new and existing CISWI units. Section 129 of the 

CAA, titled “Solid Waste Combustion,” requires the EPA to 

develop and adopt standards for solid waste incineration units 

pursuant to CAA sections 111 and 129. Section 129(a)(13)(A) of 

the CAA requires the EPA to establish performance standards, 

including emissions limitations, for “solid waste incineration 

units” generally and, in particular, for “solid waste 

incineration units combusting commercial or industrial waste.” 

CAA section 129(a)(1)(D). Section 129 of the CAA defines “solid 

waste incineration unit” as “a distinct operating unit of any 

facility which combusts any solid waste material from commercial 

or industrial establishments or the general public.” CAA section 

129(g)(1). Section 129 of the CAA also provides that “solid 

waste” shall have the meaning established by the EPA pursuant to 

its authority under the RCRA. CAA section 129(g)(6).

The December 23, 2011, proposed CISWI reconsideration rule 

granted reconsideration on a limited set of issues. 76 FR 80452. 

This final rule makes certain revisions to the final “Standards 

of Performance for Existing Sources: Commercial and Industrial 
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Solid Waste Incineration Units,” 76 FR 15704 (March 21, 2011), 

based on those reconsideration issues (76 FR 80452) and in 

response to public comment on the proposed CISWI reconsideration 

rule.

On May 18, 2011, the EPA issued a notice that delayed the 

effective dates of the March 21, 2011, CISWI rule (the “Delay 

Notice”). 76 FR 28662 (May 18, 2011). As the result of that 

action, the 2000 CISWI rule remained in effect. The Court 

vacated the Delay Notice in January 2012. However, because the 

Delay Notice delayed the effectiveness of the CISWI rule from 

May 2011 through vacature of that notice in January 2012, the 

revisions to the 2000 CISWI rule that were finalized in the 2011 

CISWI rule were never codified in the CFR, but instead appear as 

notes after the corresponding provisions of the 2000 CISWI rule 

in the CFR. Although the issues on reconsideration were limited 

in the December 2011 CISWI reconsideration proposal, we had to 

include in that proposed reconsideration rule all of the 

regulatory changes that had been made since the 2000 rule 

because the 2011 CISWI rule was not codified in the CFR. 

Specifically, we included in the December 23, 2011, proposed 

reconsideration rule all of the regulatory changes the EPA had 

made to the 2000 CISWI rule in the 2011 CISWI rule, as well as 

the changes to the 2011 CISWI rule that the EPA proposed to make 

on reconsideration. In response to the Court’s vacature of the 
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Delay Notice in January 2012, this final action lifts the delay 

of effectiveness so that the CFR can be revised to properly 

reflect the revisions to the 2000 CISWI rule that were finalized 

in the 2011 CISWI rule. This final action also contains 

regulatory text that amends the 2011 CISWI rule to address the 

reconsideration. Therefore, this final rule’s amendatory 

language differs from that of the December 2011 reconsideration 

proposal as it amends the 2011 CISWI rule instead of the 2000 

CISWI rule. This change to the amendatory baseline in no way 

alters our limitation of the issues for comment for which we 

granted reconsideration. We have provided in the CISWI docket a 

redline/strikeout file of the 2000 CISWI rule to help 

implementing agencies and affected sources to identify the sum 

total of the revisions made to the 2000 CISWI rule through 

today’s final notice pursuant to the 2011 CISWI rule and this 

final action. 

Summary of Major Provisions for the Final Reconsideration 

Rule

In general, the final rule establishes revised numeric 

emission limits for some new and existing CISWI units for 

certain of the nine pollutants listed in section 129(a)(4) of 

the CAA.1

 

1 The nine pollutants for which we must issue emission standards under section 

129 are: PM, SO2, HCl, NOX, CO, Pb, Cd, Hg, D/F. CAA section 129(a)(4).
Page 18 of 319

The EPA established standards for four subcategories of 

CISWI units in the 2011 CISWI rule: incinerators; small remote 

incinerators; ERUs; and waste-burning kilns. The 2011 CISWI rule 

also included two subcategories of ERUs. In this final rule, we 

have further subcategorized ERUs and subcategorized wasteburning kilns based on design type differences. Thus, the final 

rule includes three subcategories of ERUs and separate CO limits 

for two subcategories of waste-burning kilns.

We have further revised some of the CISWI limits proposed 

in the reconsideration notice in response to comments on CO span 

methodology and incorporated additional data, including new data 

submitted during the comment period. These changes primarily 

affect the ERU and waste-burning kiln subcategories but also 

affect some of the limits in each of the four subcategories. 

To ensure compliance with the emission limits, this final 

rule establishes stack testing and continuous monitoring 

requirements. The rule allows sources to use CEMS if an owner or 

operator chooses to do so. Continuous parameters and emissions 

levels (if used) are measured as either a 3-hour block or a 30-

day rolling average basis, depending on the parameter being 

measured and the subcategory of CISWI. 

Since sources may choose to cease or start combusting solid 

waste at any time due to market conditions or for other reasons, 

the final rule contains provisions that specify the steps 
Page 19 of 319

necessary for sources to switch applicability between this final 

rule and other applicable emission standards issued pursuant to 

CAA section 112. This rule also contains revisions to some of 

the monitoring, recordkeeping and reporting requirements. 

The effective dates for existing sources depends primarily 

on state plan approval but may be no later than the date 5 years 

after publication of this final rule in the Federal Register. 

For new sources, the effective date is either [INSERT THE DATE 6 

MONTHS AFTER PUBLICATION OF THE FINAL RULE IN THE FEDERAL 

REGISTER] or the date of startup of the source, whichever is 

later. New sources are defined as sources that began 

construction on or after June 4, 2010, or commenced 

reconstruction or modification after [INSERT THE DATE 6 MONTHS 

AFTER PUBLICATION OF THE FINAL RULE IN THE FEDERAL REGISTER].

Costs and Benefits

The final rule affects 107 existing sources located at 65 

facilities. The EPA projects an additional incinerator and five 

additional small remote incinerators to be subject to this rule 

over the next 5 years. This final rule affects multiple sectors 

of our economy including small entities. Table 1 of this 

preamble summarizes the costs and benefits associated with this 

final rule. Note however, these are the costs and benefits of 

the final 2011 CISWI rule as amended by today’s final rule and 

therefore replace the costs and benefits presented in the March 
Page 20 of 319

2011 final rule. For comparison, the 2011 final rule, at 7 

percent Discount Rate, had total net benefits [A3]of $30 to $470 

million (2008 dollars). The monetized benefits of today’s final 

rule are approximately 24% higher than those of the final 2011 

CISWI rule. [A4]A more detailed discussion of the costs and 

benefits of this final rule is provided in section II.G of this 

preamble. 

Table 1. Summary of the Monetized Benefits, Social Costs and Net 

Benefits for the Final CISWI NSPS and EG In 2015 (Millions of 

2008$)1

3 percent Discount 

Rate

7 percent Discount 

Rate

Total Monetized 

Benefits2 $420 to $1000 $390 to $940

Total Social 

Costs3 $270 $270

Net Benefits $150 to $670 $150 to $770

Non-monetized 

Benefits

Health effects from exposure to HAP 780 

tons of HCl, 2.6 tons of lead, 1.8 tons of 

Cd, 690 pounds of Hg, and 58 grams of 

dioxins/furans)[A5]

Health effects from exposure to criteria 

pollutants (20,000 tons of CO, 6,300 tons of 

SO2, 5,400 tons of NO2, and secondary 

formation of ozone) 

Ecosystem effects 

Visibility impairment 

1 All estimates are for the implementation year (2015) and are 

rounded to two significant figures. These results reflect the 

lowest cost disposal assumption.

2 The total monetized benefits reflect the human health benefits 

associated with reducing exposure to PM2.5 through reductions of 

PM2.5 precursors such as directly emitted particles, SO2, and 

NOx. It is important to note that the monetized benefits 

include many but not all health effects associated with PM2.5
Page 21 of 319

exposure. Monetized benefits are shown as a range from Pope, et 

al. (2002) to Laden, et al. (2006). These models assume that 

all fine particles, regardless of their chemical composition, 

are equally potent in causing premature mortality because there 

is no clear scientific evidence that would support the 

development of differential effects estimates by particle type. 

These estimates include the energy disbenefits valued at $3.8 

million (using the 3 percent discount rate), which do not 

change the rounded totals. CO2-related disbenefits were 

calculated using the “social cost of carbon”, which is 

discussed further in the RIA.

3The methodology used to estimate social costs for 1 year in the 

multimarket model using surplus changes results in the same 

social costs for both discount rates.

II. CISWI Reconsideration and Final Rule

A. Background Information

1. What is the history of the CISWI standards?

On December 1, 2000, the EPA promulgated NSPS and EG for 

CISWI units (60 FR 75338), hereinafter referred to as the 2000 

CISWI rule. On January 30, 2001, the Sierra Club filed a 

petition for review in the Court challenging the EPA’s final 

CISWI rule. On August 17, 2001, the EPA granted a Request for 

Reconsideration, pursuant to CAA section 307(d)(7)(B), submitted 

on behalf of the National Wildlife Federation and the Louisiana 

Environmental Action Network, related to the definition of 

“commercial and industrial solid waste incineration unit” and 

“commercial or industrial waste” in the 2000 CISWI rule. In 

granting the petition for reconsideration, the EPA agreed to 

undertake further notice and comment proceedings related to 

these definitions. On September 6, 2001, the Court entered an 
Page 22 of 319

order granting the EPA’s motion for a voluntary remand of the 

CISWI rule, without vacatur. The EPA requested a voluntary 

remand of the final CISWI rule to address concerns related to 

the EPA’s procedures for establishing MACT floors for CISWI 

units in light of the Court’s decision in Cement Kiln Recycling 

Coalition v. EPA, 255 F.3d 855 (DC Cir. 2001)(Cement Kiln). 

Neither the EPA’s granting of the petition for reconsideration, 

nor the Court’s order granting a voluntary remand, stayed, 

vacated or otherwise influenced the effectiveness of the 2000 

CISWI rule. Therefore, the remand order had no effect on the 

effectiveness of the 2000 CISWI rule. 

On February 17, 2004, the EPA published a proposed rule 

(CISWI Definitions Rule) soliciting comments on the definitions 

of “solid waste,” “commercial and industrial waste,” and 

“commercial and industrial solid waste incineration unit”. On 

September 22, 2005, the EPA published in the Federal Register

the final rule reflecting our decisions with respect to the 

CISWI Definitions Rule. The rule was challenged and, on June 8, 

2007, the Court vacated and remanded the CISWI Definitions Rule. 

In vacating the rule, the Court found that CAA section 129

unambiguously includes among the incineration units subject to 

its standards, any facility that combusts any solid waste 

material, subject to four statutory exceptions. While the Court 
Page 23 of 319

vacated the CISWI Definitions Rule, the 2000 CISWI rule remained 

in effect. 

On March 21, 2011, the EPA promulgated revised NSPS and EG 

for CISWI units (76 FR 15704)(2011 CISWI rule). That action 

constituted a partial response to the voluntary remand of the 

2000 CISWI rule and to the 2007 vacatur and remand of the CISWI 

Definitions Rule. In addition, the EPA addressed the 5-year 

technology review that is required under CAA section 129(a)(5). 

On the same day, the EPA issued a notice that it intended to 

reconsider certain aspects of the 2011 CISWI rule that warrant 

further opportunity for public comment (76 FR 15266). 

Following promulgation of the 2011 CISWI rule, the EPA 

received petitions for reconsideration from the following 

organizations (“Petitioners”): Alaska Oil and Gas 

Association/Alaska Miners Association/ConocoPhillips (AOGA), 

American Chemistry Council (ACC), American Foundry Society 

(AFS), American Iron and Steel Institute (AISI) and American 

Coke and Coal Chemicals Institute (ACCCI), Anthracite Region 

Independent Power Producers Association (ARIPPA), American 

Petroleum Institute (API) and National Petrochemical and 

Refiners Association (NPRA), Auto Industry Forum (AIF), Citizens 

Energy Group (CEG), Council of Industrial Boiler Owners (CIBO), 

Earthjustice/Sierra Club, Edison Mission Energy, Hovensa L.L.C. 

and Tesoro Hawaii Corp., Industry Coalition (AF&PA et al.), 
Page 24 of 319

JELD-WEN Inc., Portland Cement Association (PCA), Renovar Energy 

Corp., and Waste Management Inc. (WM). Copies of these petitions 

are provided in the docket (see Docket ID Number EPA-HQ-OAR2003-0119). Petitioners, pursuant to CAA section 307(d)(7)(B), 

requested that the EPA reconsider numerous provisions in the 

2011 CISWI rule. 

On May 18, 2011, the EPA issued a notice to postpone the 

effective dates of the March 21, 2011, final CISWI rule. This 

notice also requested that the public submit additional data and 

information to the EPA by July 15, 2011, for review and 

consideration in the reconsideration proceedings.

On December 23, 2011, the EPA published a proposed rule 

soliciting comment on the issues on which the EPA was granting 

reconsideration. In March 2011, the EPA had publically stated 

its intent to reconsider some of these issues. 76 FR 15266. The 

EPA limited comment in the December 23, 2011, proposed rule to 

the specific issues on which it was granting reconsideration 

which included the following:

Revising the subcategories and emission limits for ERUs and 

waste-burning kilns to reflect updated inventories and 

additional data.

Establishing limitations on fuel switching provisions.

Definitions of cyclonic burn barrels, burn-off ovens, soil 

treatment units, laboratory analysis units and space 

heaters from CISWI subcategories.

Providing an affirmative defense for malfunction events.

Revisions to the CO monitoring requirements.
Page 25 of 319

Establishing a full-load stack test requirement for CO 

coupled with continuous O2 (trim) monitoring.

Establishing a definition of “homogeneous waste.”

Responding to comments on the 2011 CISWI rule regarding the 

use of fuel variability in emission limit calculations.

Responding to comments on the 2011 CISWI rule regarding the 

review of D/F data and non-detect methodology using three 

times the detection level.

Responding to comments on the 2011 CISWI rule regarding 

providing an option for sources to use emissions averaging 

to demonstrate compliance.

Establishing a definition for foundry sand thermal 

reclamation unit.

Reinstating the definition of contained gaseous material.

Revising the definition of chemical recovery unit.

Allowing for the use of feed stream analysis or other 

supplemental information to demonstrate compliance.

Responding to comments on the 2011 CISWI rule regarding 

providing percent reduction alternative standards.

Providing parametric monitoring provisions for additional 

control device types.

Revisions to the continuous monitoring provisions for large 

ERUs.

Extending effective dates.

Technical corrections and clarifications. 

2. How is the definition of solid waste addressed in the final 

CISWI rule? 

The RCRA definition of solid waste is integral in defining 

the CISWI source category. The EPA defines NHSMs that are solid 

waste under RCRA in the final “Identification of Non-Hazardous 

Secondary Materials That Are Solid Waste” Rulemaking. In an 

action parallel to the March 21, 2011, final CISWI rule, the EPA 
Page 26 of 319

promulgated a final rule that identifies whether NHSMs are or 

are not solid waste when used as fuels or ingredients in 

combustion units. That action, hereinafter referred to as the 

“2011 NHSM final rule,” is relevant to the final CISWI rule 

because some ERUs and waste-burning kilns combust, in their 

combustion units, secondary materials that are solid waste under 

the 2011 NHSM final rule. Commercial and industrial units that 

combust solid waste are subject to standards issued pursuant to 

CAA section 129, rather than to standards issued pursuant to CAA 

section 112 that would otherwise be applicable to such units 

(e.g., units that would be boilers, process heaters or cement 

kilns if they were not combusting solid waste).

3. What is the relationship between this rule and other 

combustion rules?

These amendments address the combustion of solid waste 

materials (as defined by the Administrator under RCRA in the 

NHSM Definition rule) in combustion units at commercial and 

industrial facilities. If an owner or operator of a CISWI unit 

permanently ceases combusting solid waste, the affected unit 

would no longer be subject to the CISWI rule because the unit 

would not be a solid waste incineration unit subject to 

standards under CAA section 129. Standards issued pursuant to 

section 112 of the CAA may apply to CISWI units that cease 

combusting solid waste. For example, CAA section 112 standards 
Page 27 of 319

applicable to boilers and process heaters at major sources and 

boilers at area sources would apply to boilers and process 

heaters that cease combusting solid waste. Boilers and process 

heaters that are located at commercial and industrial facilities 

and that combust solid waste are subject to CISWI as ERUs. The 

EPA has also finalized the CAA section 112 standards for the 

Portland Cement Manufacturing Industry (75 FR 21136, September 

9, 2010). Cement kilns combusting solid waste are waste-burning 

kilns subject to CISWI, not the otherwise applicable CAA section 

112 standards.

4. What is the response to the vacatur of effective dates? 

On January 9, 2012, the Court vacated the May 18, 2011, 

Delay Notice, which delayed the effective dates of the 2011 

CISWI rule. On February 7, 2012, the EPA issued a no action 

assurance letter regarding certain notification deadlines in the 

March 2011 CISWI rule.

The EPA has conducted outreach to each EPA Regional Office

within the agency and[A6] it has not found any new CISWI units 

that commenced construction since the proposed CISWI rule was 

published on June 10, 2010. The CAA defines a “new source,” in 

part, as any source that commences construction after the 

publication date of proposed CAA section 111 and 129 standards2

 

2 The date for determining whether a source is a “new” source is the 

publication date of the proposed standards. The final rule and 
Page 28 of 319

CAA section 129(g)(2). Based on our outreach efforts, we do not 

believe there are any CISWI units that are in noncompliance with 

the NSPS contained in the final 2011 CISWI rule.

As explained above, today’s final rule amendatory text 

reflects changes to the 2011 CISWI rule, not the 2000 CISWI rule 

as in the reconsideration proposal notice. We have provided in 

the CISWI docket a redline/strikeout file of the 2000 CISWI rule 

to help implementing agencies and affected sources to identify 

the sum total of the revisions made to the 2000 CISWI rule 

pursuant to the 2011 CISWI rule and this final action.

B. Summary of This Final Rule

As stated above, the December 23, 2011, proposed rule 

addressed specific issues and provisions the EPA identified for 

reconsideration. This summary of the final rule reflects the 

agency’s final action in regards to those provisions identified 

for reconsideration and on other discrete matters identified in 

response to comments or data received during the comment period. 

Information on other provisions and issues not proposed for 

reconsideration is contained in the notice and record for the 

2011 CISWI rule. 76 FR 15704 (March 21, 2011).

1. Subcategories of Affected Units and Emission Standards 

 

reconsideration proposal contained a typographical error in 40 CFR 

60.2015(a)(1) that did not specify the June 4, 2010, proposal date.
Page 29 of 319

This final rule defines a CISWI unit, in part, as any 

combustion unit at a commercial or industrial facility that is 

used to combust solid waste (as defined under RCRA)(40 CFR 

60.2265 (NSPS) and 60.2875 (EG)). We have established standards 

in this final rule for the following four subcategories of CISWI 

units: incinerators (i.e., units designed to burn discarded 

waste materials for the purpose of disposal); small, remote 

incinerators; ERUs (i.e., units that would be boilers or process 

heaters if they did not combust solid waste); and waste burning 

kilns (i.e., units that would be cement kilns if they did not 

combust solid waste). We further subcategorized ERUs into three 

subcategories and waste burning kilns into two subcategories for 

CO emission limits only. Changes to the subcategories made since 

proposal are discussed below in section II.C of this preamble: 

“Summary of Significant Changes Since Proposal.” 

The final rule emission limits for new and existing sources 

in the solid-fuel burning ERU subcategory and the waste-burning 

kilns subcategories were revised based on changes to the 

inventories for those subcategories as discussed below in 

section II.C of this preamble: “Summary of Significant Changes 

Since Proposal.” Tables 2 and 3 of this preamble present the 

final emission limits for all subcategories for existing and new 

sources, respectively.
Page 30 of 319

Table 2. Comparison of Existing Source MACT Floor Limits for 

2000 CISWI Rule and the Final MACT Floor Limits 

Pollutant 

(units)a

Incinerators 

(2000 

CISWI 

limit) 

CISWI Subcategories

Incinerators ERUs -

Solids

ERUs –

Liquid/Gas

Wasteburning 

kilns

Small, 

remote 

incinerators

HCl (ppmv) 62 29 0.20 

(bioma

ss 

units)

/

21 

(coal 

units)

14b 3.0b 300

CO (ppmv) 157 17 260 

(bioma

ss 

units)

/

95 

(coal 

units)

35 110 (long 

kilns) / 

790 

(preheater 

/ 

precalcine

r)

64

Pb 

(mg/dscm)

0.04 0.015 0.014b

(bioma

ss 

units) 

/ 

0.013b

(coal 

units)

0.096 0.014b 2.1

Cd 

(mg/dscm)

0.004 0.0026 0.0014

b

(bioma

ss 

units) 

/ 

0.058 

(coal 

units) 

0.023 0.0014b 0.95
Page 31 of 319

Pollutant 

(units)a

Incinerators 

(2000 

CISWI 

limit) 

CISWI Subcategories

Incinerators ERUs -

Solids

ERUs –

Liquid/Gas

Wasteburning 

kilns

Small, 

remote 

incinerators

Hg 

(mg/dscm)

0.47 0.0048 0.0022 

(bioma

ss 

units) 

/ 

0.0028 

(coal 

units)

0.031b 0.011b 0.0053

PM, 

filterable 

(mg/dscm)

70 34 11 

(bioma

ss 

units) 

/ 60 

(coal 

units)

110 4.6 270

Dioxin, 

furans, 

total 

(ng/dscm)

(no 

limit) 

4.6 0.52b

(bioma

ss 

units) 

/ 

0.51b

(coal 

units)

2.9b 1.3 4,400

Dioxin, 

furans, 

TEQ 

(ng/dscm)

0.41 0.13 0.12 

(bioma

ss 

units) 

/ 

0.075b

(coal 

units)

0.32b 0.075b 180

NOx (ppmv) 388 53 290 

(bioma

ss 

units)

/

340 

(coal 

units)

76 630 190
Page 32 of 319

Pollutant 

(units)a

Incinerators 

(2000 

CISWI 

limit) 

CISWI Subcategories

Incinerators ERUs -

Solids

ERUs –

Liquid/Gas

Wasteburning 

kilns

Small, 

remote 

incinerators

SO2 (ppmv) 20 11 7.3 

(bioma

ss 

units)

/

650 

(coal 

units)

720 600 150

a All emission limits are expressed as concentrations corrected to 7 percent 

O2.

b See the memorandum "CISWI Emission Limit Calculations for Existing and New 

Sources for the Reconsideration Final Rule" for details on this calculation.

Table 3. Comparison of New Source MACT Floor Limits for 2000 

CISWI Rule and the Final MACT Floor Limits 

Pollutant 

(units)a

Incinerators 

(2000 

limit)

Final CISWI Subcategories

Incinerators ERUs –

Solids

ERUs –

Liquid/Gas

Wasteburning 

kilns

Small, 

remote 

incinerators

HCl (ppmv) 62 0.091 0.20c

(biomass 

units)/

21 (coal 

units)

14b 3.0b 200

CO (ppmv) 157 17 240 

(biomass 

units)/

95 (coal 

units)

35 90 (long 

kilns) / 190 

(preheater / 

precalciner)

13

Pb 

(mg/dscm)

0.04 0.015b

0.014b

(biomass 

units) / 

0.013b

(coal 

units)

0.096 0.014b 2.0
Page 33 of 319

Pollutant 

(units)a

Incinerators 

(2000 

limit)

Final CISWI Subcategories

Incinerators ERUs –

Solids

ERUs –

Liquid/Gas

Wasteburning 

kilns

Small, 

remote 

incinerators

Cd 

(mg/dscm)

0.004 0.0023 0.0014c

(biomass 

units) / 

0.058 

(coal 

units)

0.023 0.0014b 0.67

Hg 

(mg/dscm)

0.47 0.00084b

0.0022c

(biomass 

units) / 

0.0028 

(coal 

units)

0.00091d 0.0037b 0.0035

PM, 

filterable 

(mg/dscm)

70 18 5.1 

(biomass 

units) / 

60 (coal 

units)

110 2.2 270c

Dioxin, 

furans, 

total 

(ng/dscm)

(no 

limit) 

0.58b 0.52b

(biomass 

units) / 

0.51b

(coal 

units)

(no limit) 0.51b 1,800

Dioxin, 

furans, 

TEQ 

(ng/dscm)

0.41 0.13 0.076b

(biomass 

units) / 

0.075b

(coal 

units)

0.093d 0.075b 31

NOx (ppmv) 388 23 290c

(biomass 

units)/

340 

(coal 

units)

76 200b 170

SO2 (ppmv) 20 11c

7.3c

(biomass 

units)/

650 

(coal 

units)

720 130 1.2
Page 34 of 319

a All emission limits are measured at 7 percent O2.

b See the memorandum “CISWI Emission Limit Calculations for Existing and New 

Sources for the Reconsideration Final Rule” for details on this calculation.

c The NSPS limit equals the EG limit. The EG limit was selected as the NSPS 

limit.

d D/F TEQ and Hg limits for ERUs – liquid/gas were replaced with D/F TEQ 

limits for liquid fuel major source boilers. See “CISWI Emission Limit 

Calculations for Existing and New Sources for the Reconsideration Final Rule" 

for details.

2. Fuel Switching Provisions 

The EPA is finalizing the proposed fuel switching 

provisions that address the situation where CISWI units cease 

combusting solid waste, and where existing commercial and 

industrial combustion units begin combusting solid waste (40 CFR 

60.2330 for existing units and 40 CFR 60.2710 for new units). 

Units that cease combusting solid waste remain subject to CISWI 

for at least 6 months after solid waste is last added to the 

combustion chamber. After 6 months, sources must either comply 

with any applicable section 112 standard or, if they intend to 

combust solid waste in the future, opt to remain subject to 

CISWI and continue to comply with the applicable provisions. 

Combustion units located at commercial or industrial facilities 

that begin combusting solid waste are solid waste incineration 

units on the date they begin combusting solid waste. Existing 

units that begin combusting solid waste within 6 months of the 

effective date of the CISWI EG must comply with the standards on 

the effective date of those standards. Existing units that begin 

combusting solid waste after the effective date of the CISWI EG 
Page 35 of 319

must comply with those standards at the time the unit begins 

combusting solid waste.

3. Definitions of Cyclonic Burn Barrels, Burn-off Ovens, Soil 

Treatment Units, Laboratory Analysis Units and Space Heaters

We are finalizing the proposed definitions for cyclonic 

burn barrels, burn-off ovens, soil treatment units, and 

laboratory analysis units. We have revised the proposed 

definition for space heaters to clarify applicability for units 

that meet the requirements of 40 CFR 279. The final definitions 

describe the types of units and state that these different types 

of units are not incinerators, small remote incinerators, ERUs, 

or waste burning kilns. The EPA is including these definitions 

in the final rule to differentiate these units from the units 

for which the agency established standards in the 2011 CISWI 

rule and this final action.

4. Affirmative Defense for Malfunction Events

The EPA is finalizing the proposed affirmative defense to 

civil penalties for malfunction events. The EPA first included 

an affirmative defense in the 2011 final rules in an attempt to 

balance a tension, inherent in many types of air regulation, to 

ensure adequate compliance while simultaneously recognizing that 

despite the most diligent of efforts, emission standards may be 

violated under circumstances beyond the control of the source. 

This final reconsideration attempts to add clarification to the 
Page 36 of 319

affirmative defense and provided opportunity for additional 

public comment and response. 

Sources are required to comply with the CISWI standards at 

all times, and the EPA recognizes that even equipment that is 

properly designed and maintained can sometimes fail and that 

such failure may cause an exceedance of the relevant standard. 

The EPA must establish emission standards that “limit the 

quantity, rate, or concentration of emissions of air pollutants 

on a continuous basis.” 42 U.S.C. § 7602(k)(defining “emission

limitation and emission standard”). See generally Sierra Club v. 

EPA, 551 F.3d 1019, 1021 (D.C. Cir. 2008). The affirmative 

defense for malfunction events meets this requirement by 

ensuring that even where there is a malfunction, the emission 

standard is still enforceable through injunctive relief. See 

generally, Luminant Generation Co. v EPA, 2012 U.S. App. LEXIS 

15722 (5th Cir. 2012) (upholding EPA’s approval of affirmative 

defense provisions in a CAA State Implementation Plan). While 

“continuous” standards, on the one hand, are required, there is 

also case-law indicating that in many situations it is 

appropriate for the EPA to account for the practical realities 

of technology. For example, in Essex Chemical v. Ruckelshaus, 

486 F.2d 427, 433 (D.C. Cir. 1973), the D.C. Circuit 

acknowledged that in setting standards under CAA section 111 

“variant provisions” such as provisions allowing for upsets 
Page 37 of 319

during startup, shutdown and equipment malfunction “appear 

necessary to preserve the reasonableness of the standards as a 

whole and that the record does not support the ‘never to be 

exceeded’ standard currently in force.” See also, Portland 

Cement Association v. Ruckelshaus, 486 F.2d 375 (D.C.Cir. 1973). 

Though intervening case-law such as Sierra Club v. EPA and the 

CAA 1977 amendments call into question the relevance of these 

cases today, they support the EPA’s view that a system that 

incorporates some level of flexibility is reasonable.

The affirmative defense provisions allow sources to avoid 

civil penalties for exceedances caused by a malfunction event if 

the source demonstrates by a preponderance of the evidence that 

the malfunction event meets the definition of malfunction in 40 

CFR 60.2. By incorporating an affirmative defense, the EPA has 

formalized its approach to upset events beyond the control of 

the source. In a Clean Water Act setting, the Ninth Circuit 

required this type of formalized approach when regulating 

“upsets beyond the control of the permit holder.” Marathon Oil 

Co. v. EPA, 564 F.2d 1253, 1272-73 (9th Cir. 1977). See also, 

Mont. Sulphur & Chem. Co. v. United States EPA, 2012 U.S. App. 

LEXIS 1056 (Jan 19, 2012)(rejecting industry argument that 

reliance on the affirmative defense was not adequate). But see, 

Weyerhaeuser Co. v. Costle, 590 F.2d 1011, 1057-58 (D.C. Cir. 

1978) (holding that an informal approach is adequate). The 
Page 38 of 319

affirmative defense provisions give the EPA the flexibility to 

both ensure that its emission standards are “continuous” as 

required by 42 U.S.C. § 7602(k), and account for unplanned 

upsets and thus support the reasonableness of the standard as a 

whole. In addition, the affirmative defense provisions are 

designed to ensure that steps are taken to correct the 

malfunction, minimize emissions during the malfunction, and 

prevent future malfunctions.

5. Oxygen Correction Requirements and CO Monitoring Requirements

We are finalizing provisions for calculating the 30-day CO 

rolling average that allow uncorrected CEMS reading to be used 

during the period of operation from a cold start to bring the 

combustion unit up to minimal normal operating temperature. We 

are also allowing uncorrected CEMS readings to be used in 30-day 

average calculations for the period of operation following the 

last waste material (or material feed for waste burning kilns) 

being fed to the combustion unit during shutdown procedures of 

the unit. For every type of CISWI unit except waste-burning 

kilns, the period of time allowed for uncorrected CEMS data 

during a startup shall be 48 hours or less per startup event and 

shall be 24 hours or less for each shutdown event. For wasteburning kilns, the period of startup begins when the kiln’s 

induced fan is turned on and continues until continuous feed is 

introduced into the kiln, at which time the kiln is in normal 
Page 39 of 319

operating mode. Shutdown begins when feed to the kiln is halted. 

[A7]Sources must indicate in the CEMS data records which CEMS data 

are obtained during the startup and shutdown periods. Since the 

O2 correction calculation will affect all corrected CEMS data, 

we have expanded these provisions in the final rule to allow for 

uncorrected CEMS data for any pollutant that sources elect to 

measure continuously with CEMS and calculate 30-day rolling 

averages to demonstrate continuous compliance.

Additionally, we have finalized removal of continuous CO 

monitoring requirements for new and existing ERU units. We are 

instead requiring annual CO stack tests and continuous O2

monitoring and we are allowing CO monitoring with CEMS as a 

compliance alternative. We have also removed the continuous CO 

monitoring requirements for new CISWI units in the other 

subcategories, but sources may demonstrate compliance using CO 

CEMS if they so choose. The authority to use uncorrected CEMS 

data during startup and shutdowns discussed above applies to all 

CISWI sources that elect to demonstrate compliance with any 

emission limits with a CEMS instead of performing annual stack 

tests. Changes to the CO and other optional CEMS monitoring 

requirements made since proposal are discussed below in Section 

II.C of this preamble: “Summary of Significant Changes Since 

Proposal.” 
Page 40 of 319

6. Full-load Stack Test Requirement for CO Coupled With 

Continuous O2 Monitoring 

We are finalizing the full-load stack test and continuous 

O2 monitoring provisions in today’s action that afford the 

ability for existing sources to use their current O2 analyzer 

and O2 trim systems to demonstrate continuous compliance. Based 

on comments received, we have made some clarifying changes to 

these provisions to be clear that existing O2 trim systems and 

O2 monitors may be used to demonstrate continuous compliance, as 

well as clarifications on establishing the operating limits for 

O2 content. Changes to the continuous O2 monitoring requirements 

made since proposal are discussed below in section II.C of this 

preamble: “Summary of Significant Changes Since Proposal.” 

7. Non-detect Methodology Using Three Times the Detection Level

Since proposal, the EPA continued its review of sampling 

volumes and detection levels across various emission testing ICR 

efforts on various combustion sources to encompass additional 

pollutants measured using EPA Reference Method 29 (See 

memorandum “Updated data and procedure for handling below 

detection level data in analyzing various pollutant emissions 

databases for MACT and RTR emissions limits” in the CISWI 

docket). As a result of this analysis, we have determined 

recommended values for three times the representative detection 
Page 41 of 319

level that may be used as a minimum emission limit value that 

can be accurately measured by most laboratories for Cd and Pb.3

Furthermore, based on comments on our application of this 

non-detect methodology approach to CO data measured using 

instrument methods, we have made some necessary modifications to 

the span calculation approach used in the proposed rule. Changes 

to the emission limits for Cd, Pb and the span adjustment 

calculations for CO made since proposal are discussed below in 

section II.C of this preamble: “Summary of Significant Changes 

Since Proposal.”

8. Definitions for Foundry Sand Thermal Reclamation Unit and 

Chemical Recovery Unit

We are finalizing the proposed definitions of “foundry sand 

thermal reclamation unit” and “chemical recovery unit” to 

clarify that these units are not incinerators, waste-burning 

kilns, ERUs or small, remote incinerators under subparts CCCC or 

DDDD.

9. Definition of Contained Gaseous Material

In today’s final rule, we have reintroduced and finalized 

the definition for “contained gaseous material” as found in the 

2000 CISWI rule as proposed. As discussed earlier, the Court’s 

vacature of the Delay Notice now requires this definition to be 

 

3 The RDL methodology is consistent with the RDL methodology outlined in the 

December 2011 reconsideration proposal. 76 FR 80463. 
Page 42 of 319

reintroduced since we are now amending the 2011 CISWI rule 

instead of making amendments to the 2000 CISWI rule as when we 

published the December 2011 reconsideration proposal. 

10. Parametric Monitoring Provisions for Additional Control 

Device Types

In the proposed rule, we requested comment on whether there 

were additional control device types that we should identify 

monitoring parameters for in the rule. We received comments on 

this topic and, in today’s final rule, are including monitoring 

provisions for sorbent injection rate for dry scrubber control 

devices (40 CFR 60.2165 and 40 CR 60.2730). We have also 

clarified that sources that elect to use optional CEMS to 

monitor continuous compliance for Hg, D/Fs or NO2 may do so as a 

substitute for parametric monitoring of ACI and SNCR control 

devices, respectively. Changes to the parametric monitoring 

provisions made since proposal are discussed below in section 

II.C of this preamble: “Summary of Significant Changes Since 

Proposal.”

11. Particulate Matter Continuous Monitoring Provisions for 

Large ERUs and Waste-burning Kilns

In today’s rule, we are finalizing some revisions to the 

monitoring requirements for ERUs with an annual average heat 

input rate greater than 250 MMBtu/hr and extending the same PM 

continuous monitoring provisions to waste-burning kilns. In the 
Page 43 of 319

final 2011 CISWI rule, these units were required to monitor 

continuously for PM using a PM CEMS; however, the PM CEMS 

technology may not be sufficient to certify accurate monitor 

performance in the PM concentration range of the CISWI biomass 

ERU and waste-burning kiln limits. Therefore, we are requiring 

continuous PM parameter monitoring systems for these units 

similar to those being required for major industrial boilers and 

utility boilers. The EPA is further requiring that a sitespecific parametric operating limit be established during the 

performance test, that there be continuous monitoring of that 

parametric limit using a PM CPMS, that an exceedance of that 

site-specific operating limit be reported as a deviation and 

trigger immediate corrective action and a Method 5 performance 

test within 45 days. 

To be consistent with the boiler rules, we have revised all 

operating parameter averaging for ERU units to be on a 30-day 

rolling average and allowed the sorbent injection parameter to 

be adjusted for varying ERUs based on load. Changes to the PM 

continuous monitoring provisions and operating parameter 

provisions made since proposal are discussed below in section 

II.C of this preamble: “Summary of Significant Changes Since 

Proposal.”

12. Revised Definition of Waste-burning Kiln
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This final rule includes a definition of waste-burning kiln 

that has been revised since the March 2011 CISWI Rule. This 

definition helps clarify the EPA’s intent regarding which types 

of Portland cement kilns are considered subject to CISWI 

standards and which kilns are subject to the Portland cement 

NESHAP. Since proposal, some additional language was added to 

this definition to further clarify our proposed definition. 

Changes to the definition of waste burning kiln made since 

proposal are discussed below in section II.C of this preamble: 

“Summary of Significant Changes Since Proposal.”

13. Revised Definition of Solid Waste

In the March 21, 2011, final CISWI rule, we removed the 

definition of solid waste that was present in the 2000 CISWI 

Rule in light of the definition of solid waste in the final NHSM 

rule. Because applicability of section 129 hinges on sources 

combusting solid waste, we believe it is appropriate to include 

a definition of that term in the CISWI rule. For that reason, 

the final rule contains a definition of solid waste that refers 

to the final NHSM rule at 40 CFR 241.2. 

14. Compliance Dates

In the final rule, we are revising the compliance dates for 

new and existing CISWI units to reflect the effective dates of 

this final rule. The compliance date for existing sources 

depends primarily on state plan approval but may be no later 
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than the date 5 years after publication of this final rule in 

the Federal Register. The EG are implemented through a state 

implementation plan or a federal plan. Under the final 

amendments to the EG, and consistent with the CAA section 129, 

revised state plans containing the revised existing source 

emission limits and other requirements in the final amendments 

are due within 1 year after promulgation of the final 

reconsideration amendments. States must submit revised state 

plans to the EPA by [INSERT THE DATE 12 MONTHS AFTER PUBLICATION 

OF THIS FINAL RULE IN THE FEDERAL REGISTER]. The EPA will revise 

the existing federal plan to incorporate any changes and other 

requirements that the EPA has promulgated. The federal plan 

applies to CISWI units in any state without an approved state 

plan. Additional discussion of the state plan implementation 

schedule can be found at 76 FR 15711. 

For new sources, the compliance date is either [DATE 6 

MONTHS AFTER PUBLICATION OF THE FINAL RULE IN THE FEDERAL 

REGISTER] or the date of startup of the source, whichever is 

later. New sources are defined as sources that began 

construction on or after June 4, 2010, or commenced 

reconstruction or modification after [DATE 6 MONTHS AFTER 

PUBLICATION OF THE FINAL RULE IN THE FEDERAL REGISTER].

C. Summary of Significant Changes Since Proposal

1. Revision of the Subcategories
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Energy Recovery Units

In the final 2011 CISWI Rule, we established separate 

subcategories based on the types of fuels and wastes ERUs were 

designed to burn. Energy Recovery Units (e.g., units that would 

be boilers and process heaters but for that fact that they 

combust solid waste) designed to burn gaseous fuels and liquids 

that are solid waste were included in one primary subcategory 

and the other primary subcategory was for units designed to burn 

solid fuels or predominantly non-coal solid materials. In the 

final 2011 CISWI rule, the solid fuel ERU subcategory was 

further divided into separate subcategories for coal and biomass 

units, with separate limits for CO, NOx and SO2 to account for 

significant differences in unit design for these two types of 

fuels and the impacts the different unit designs have on 

emissions of these pollutants. 

Because the public was not afforded an opportunity to 

comment on the revision to the ERU subcategory, we identified 

this as a reconsideration issue in the March 21, 2011, notice of 

intent to reconsider certain aspects of the 2011 CISWI Rule. 

Certain petitions for reconsideration supported the further 

subcategorization of the solid-fuel ERU subcategory and 

suggested that all nine emission limits should be divided 
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between coal and biomass ERUs, instead of only having different 

limits for CO, NOx and SO2. 

We granted reconsideration of our subcategorization 

approach for ERUs and proposed to establish different emission 

limits for PM, Cd, Pb, and D/F between coal and biomass units, 

in addition to establishing different limits for CO, NOx and 

SO2. We also solicited comment on whether we should also 

subcategorize solid-fuel ERUs for HCl and Hg. 

Based on comments and information received during the 

comment period, we have determined that it is appropriate to 

subcategorize solid fuel ERUs for all nine CAA section 129 

pollutants. We recognize that there are significant design and 

operational differences between biomass and coal ERU units that 

impact the generation of all nine regulated pollutants, and, for 

this reason, we are establishing separate emission standards for 

all nine pollutants from coal and biomass ERUs in this final 

rule.

In addition, since issuing the proposed reconsideration 

CISWI rule, we have received comments and data which allowed us 

to update our inventory of ERUs. The inventory adjustments we 

made more accurately reflect the inventory of solid waste 

combustion units. Based on comments from the operator of the 

units, we removed three units from the final rule inventory of 
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biomass ERUs that were determined to be non-waste burning units 

and we re-analyzed the emission limits for the solid-biomass ERU 

subcategory. The commenter explained that, although permitted to 

burn materials that would be considered solid waste, these units 

had ceased burning the materials in question several years ago 

and would not recommence burning these in the future. Thus, at 

the time of testing, these units were not solid waste 

incineration units. We also received additional CO emissions 

data and re-analyzed the performance of the best-performing ERU 

in the solid-coal ERU subcategory. The emission limits in this 

final rule reflect the new inventory and emission data received; 

however, we have used the same methodology as in the 2011 CISWI 

rule and December 23, 2011, reconsideration proposal for 

establishing the emission limits. 

Waste-burning Kilns

Prior to the reconsideration proposal, the EPA performed an 

analysis of the materials being combusted in the entire 

inventory of Portland cement kilns in light of the final NHSM 

rule (See memorandum “Revised Floors without Kilns that Would 

have been CISWI Kilns Had the Solid Waste Definition Applied” in 

the CISWI docket). As a result of this analysis, we added 11 

kilns to our inventory of waste-burning kilns. In addition to 

this, we further reviewed the Portland cement emissions test 

records and identified some additional test data for kilns that 
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were added to the CISWI inventory following the March 21, 2011, 

final rule publication. This newly-identified data was extracted 

and compiled into the CISWI database, and then the MACT floor 

emission limits were re-calculated in the December 23, 2011, 

proposed rule to reflect the updated inventory and additional 

data. Following proposal, we were also notified of one 

additional waste-burning kiln and that one of the kilns in the 

inventory was not burning waste materials. We made these 

adjustments to our inventory, bringing the total waste-burning 

kiln inventory to 23 kilns. We recalculated the standards in 

this final rule to include all 23 waste burning kilns. 

As with the new ERU standards, we have used the same 

methodology to establish today’s emission limits as we used for 

the final 2011 CISWI rule. We have also retained the emissions 

concentration basis for the standards. However, Table 4 of this 

preamble presents the emission limits for PM, NOx, SO2 and Hg on 

a production basis for comparison. 

Table 4. Waste-burning Kiln Emission Limits Expressed in 

Production Basis

Pollutant (units) Existing kilnsa New kilnsa

Hg (lb/MM ton clinker) 58 21

PM (lb/ton clinker) 0.026 0.013

NOx(lb/ton clinker) 6.7 2.1

SO2(lb/ton clinker) 8.9 1.9

a. Approximate. 

Small remote incinerators
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After the reconsideration proposal, we received additional 

information from stakeholders of additional units in operation 

and planned for operation within the next year or two that would 

qualify as small remote incinerators. The resulting changes 

included moving one unit from the small remote incinerator 

subcategory to the incinerator subcategory due to the unit’s 

proximity to a landfill in Alaska. An additional 15 small 

remote incinerators were added to our inventory of existing 

units, bringing the total of this subcategory to 28 units. 

2. Revisions to the Monitoring Requirements

After the March 21, 2001, final rule, petitioners 

identified computational issues for correcting CO concentration 

measurements to 7 percent O2 for periods when the O2 content of

the flue gas approaches the ambient air O2 content during 

startup and shutdown periods for sources that demonstrate 

compliance with the CO limit using CEMS. The equation for the 7 

percent O2 correction is X ppm CO*(20.9 – 7)/(20.9 - %O2 of flue 

gas stream). As seen by this equation, as the flue gas stream O2

content gets closer to 20.9, the value of X is multiplied by an 

ever increasing factor. For example, when the stack gas O2

content is 4 percent, the factor is 0.82. If the stack gas O2

content is 20 percent, the factor increases to 15.4. Therefore, 

a flue gas CO concentration reading of 100 ppm would be 
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corrected to 82 ppm for a stack gas at 4 percent O2 content, but 

would become a 1,540 ppm corrected concentration for a stack gas 

at 20 percent O2 content. In the extreme, at a 20.8 percent 

stack gas concentration (i.e., approximating ambient air O2

content), the same 100 ppm measurement would be corrected to 

13,900 ppm.

Petitioners noted that O2 contents relatively close to 

ambient air often are maintained during combustion unit startup 

and shutdown in order to safely operate the combustion unit. 

Therefore, CO readings during these periods would be multiplied 

by an uncharacteristically high correction factor, and the 

resulting corrected CO concentrations inflated due to the 7 

percent O2n correction. Petitioners and commenters presented 

data that show these corrected data points would have the 

potential to drive the 30-day rolling average values beyond the 

emission limit for the affected units.

Petitioners suggested various approaches to remedy this 

situation, with one being to not require the 7 percent O2

correction requirement during unit startup and shutdown for 

sources that demonstrate compliance with the CO limit using 

CEMS. In other words, the CEMS data as reported at stack gas 

concentration without O2 correction would be included in the 

rolling average calculations for periods when the combustion 
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unit is either being started up or shutdown instead of applying 

the O2 correction to that data before it is included in the 

calculation of the 30 day rolling average. During all other 

operating periods, the CEMS data would be corrected to a 7 

percent O2 concentration prior to calculating the rolling 

average. Stated otherwise, the data obtained during startup and 

shutdown, which will not include the 7 percent O2 correction, 

will be added to the O2 corrected data collected during all 

other periods to calculate the 30-day average that is used to 

determine continuous compliance with the applicable CO limit for 

sources that demonstrate compliance using CEMS. 

Prior to issuing the reconsideration proposal, we received 

data for one unit in one subcategory (coal ERUs) that indicated 

startups usually occur over a 4-hour period and shutdowns occur 

over a 1 hour period. Therefore, we proposed provisions for 

calculating the 30-day CO rolling average that would allow the 

source to use CEMS data that does not include the O2 correction 

to be used during the first 4 hours of operation from a cold 

start and the 1 hour of operation following the last waste 

material being fed to the combustion unit during shutdown 

procedures of the unit. Since proposal, however, we received 

comments on this provision, primarily pointing out that longer 

periods are required to protect combustion equipment from rapid 
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temperature swings, which could cause damage to the fireboxes or 

kiln surfaces. Commenters also contended that the limited 

information concerning the startup and shutdown periods during 

which the O2 correction would not be required did not reflect 

the needs for all combustor types or control device 

configurations. We have therefore revised the shutdown and 

startup period of operation to be more generally applicable to 

CISWI units. In the case of ERUs, incinerators and small remote 

incinerators, we determined that the startup period should 

include the times prior to the source reaching the minimal 

operating temperature, but in no case longer than 48 hours. For 

shutdown, we determined as at proposal that shutdown begins 

after the last waste has been fed to the combustor prior to 

shutdown but we have revised the final rule to indicate that the 

shutdown period may not exceed 24 hours. We have, therefore, 

specified in the final rule an UL of 48 hours for startup 

periods to use uncorrected CEMS data and 24 hours for shutdown 

periods to use uncorrected CEMS data for ERUs, incinerators and 

small remote incinerators. For waste-burning kilns, these 

periods are triggered off of material feed to the kiln rather 

than solely waste feed. This addresses the fact that kilns, 

unlike other CISWI units, are producing product rather than 

solely disposing of waste or recovering energy. Therefore, for 

waste-burning kilns, startup begins when the kiln’s induced fan 
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is turned on and continues until continuous feed is introduced 

into the kiln at which time the kiln is in normal operating 

mode. Shutdown begins when feed to the kiln is halted.

As at proposal, sources must indicate in the CEMS data 

records which CEMS data are uncorrected because they were 

obtained during the startup and shutdown period. 

The O2 correction issue described above for CO CEMS data 

collected during startup and shutdown applies equally to other 

pollutants measured with a CEMS that is corrected to 7 percent 

O2. The final CISWI rule allows sources to demonstrate 

compliance with any of the standards using CEMS, and, for this 

reason, we have expanded authorization to use uncorrected CEMS 

data during periods of startup and shutdown to all pollutants 

for which a source demonstrates compliance with CEMS. In the 

final rule, the 7 percent O2 correction is not required during 

startup and shutdowns for any CISWI sources that elect to 

demonstrate continuous compliance with any of the emission 

limits with a CEMS instead of stack tests.

3. Oxygen Monitoring Requirements

At proposal, we included provisions and definitions in an 

attempt to ensure that sources would be able to use existing O2

monitoring systems to meet the continuous O2 monitoring 

requirements. However, commenters identified potential issues 
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with our proposed provisions and definitions. To address these 

commenters’ concerns, we have revised the provisions in 40 CFR 

60.2165 and 40 CFR 60.2730 to clarify the methodology for 

establishing and monitoring the O2 level. Furthermore, the 

definition of “oxygen analyzer system” has been revised to 

clarify the appropriate locations and nomenclature of possible 

existing monitoring systems so that their use to meet these 

requirements is fully enabled.

4. Removal of the Definition of Homogeneous Waste

The EPA included in the final 2011 CISWI Rule a definition 

of homogenous waste and a process for evaluating claims that a 

particular waste stream is homogenous. The definition was added 

to the 2011 CISWI rule in response to comment. Because the 

determination of homogeneity of a waste stream is relevant to 

applicability of CAA section 129 to qualifying small power 

producers and qualifying cogeneration facilities, we determined 

it was reasonable to include a definition of “homogenous waste” 

and a process by which sources could obtain a determination that 

a waste stream is homogenous from the EPA. 

In the 2011 CISWI Rule, the EPA stated that a determination 

concerning whether a waste is homogeneous is made on a case-bycase basis. The EPA added provisions to the CISWI final rule 

that require source owners or operators seeking the exemption 

from the definition of solid waste incineration unit contained 
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in CAA section 112(g)(1)(B) to submit a request for a 

homogeneous waste determination to the EPA. The rule required 

the request to include information describing the materials to 

be combusted and why they believe the waste is homogeneous. The 

2011 CISWI rule also indicated that the determination of what 

constitutes a homogeneous waste is not delegable to the state or 

local agencies. In the December 23, 2011, reconsideration 

proposal, we proposed the definition of “homogeneous waste” and 

the provisions for making homogeneous waste determinations that 

were included in the 2011 CISWI rule.

Commenters generally did not agree with the proposed 

definition, arguing that the definition introduced ambiguities 

and stipulations that would prevent classification of many 

materials (including fossil fuels) as being “homogeneous.” We 

reevaluated the definition in light of the comments and 

determined that the definition was unduly restrictive; however, 

we also determined that commenters proposed alternative 

definitions were equally problematic. We further recognized that 

due to the variability of waste and the fact specific nature of 

these determinations that a definition of homogenous waste was 

neither necessary nor preferable. Therefore, the final rule does 

not include a definition of “homogeneous waste”. We are 

retaining, however, the requirement that qualifying small power 

producers and qualifying cogeneration facilities that combust 
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solid waste obtain a determination from the EPA that such waste 

is homogenous. (40 CFR 60.2020 and 40 CFR 60.2555). [A8]

5. Non-detect Methodology Using Three Times the Detection Level

Prior to reconsideration proposal, the EPA conducted a 

review of sampling volumes and detection levels across various 

emission testing ICR efforts on various combustion sources (See 

memorandum “Updated data and procedure for handling below 

detection level data in analyzing various pollutant emissions 

databases for MACT and RTR emissions limits” in the CISWI 

docket). As a result of this analysis, we determined recommended 

values for three times the RDL (3xRDL) that may be used as a 

minimum emission limit value that can be accurately measured by 

most laboratories. These recommended values were then compared 

with calculated emission limits and, if the calculated limit was 

less than the recommended 3xRDL, the 3xRDL value was selected as 

the limit. Since the December 23, 2011, reconsideration proposal 

was published, we have continued our review and determined 3xRDL 

values for additional metals measured using EPA Reference Method 

29. These include recommended values for Cd and Pb and we have 

applied this methodology to those emission limits in addition to 

the D/F and Hg limits that were reevaluated in the 

reconsideration proposal. As discussed in the reconsideration 

proposal, the premise for this approach is the same as described 

in the final 2011 CISWI rule but using a broader data set to 
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establish the 3xRDL value. We have not changed the methodology 

of the emission limit calculation or tabulation of the three 

times the detection limit value that was used in the final 2011 

CISWI rule.

Since reconsideration proposal, some commenters have noted 

that the EPA Method 5 minimum catch values were below levels 

established in similar studies on this reference method. In 

light of these comments, we have reconsidered the 1 mg minimum 

catch value used in the reconsideration proposal and are now 

using a 2 mg minimum catch in establishing the final rule 

emission limits. Our review and determination of the 2 mg 

minimum catch are discussed in “Revision of Estimated Method 5 

Detection Limit” in the CISWI docket. 

In a similar fashion, the CO span adjustment methodology 

has been further refined in consideration of comments on the 

approach used to adjust CO instrumental test methods readings in 

reconsideration proposal. The methodology for adjusting CO 

emission test run data to reflect the limitations from the 

instrument span used at testing is described in the “CISWI 

Emission Limit Calculations for Existing and New Sources for the 

Reconsideration Final Rule" memorandum in the CISWI docket.

6. Parametric Monitoring for Additional Control Device Types

In the December 23, 2011, reconsideration proposal, we

stated that we believed the control devices with monitoring 
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provisions expressly identified in the rules should encompass 

most types of control devices that we anticipate the various 

types of CISWI units will use to meet the emission limits. 

However, recognizing that a source might want to employ another 

type of control that is not addressed, we provided provisions 

for sources to petition for specific operating limits for 

alternative control devices to be established during a 

performance test. These provisions also allow specific operating 

limits to be established for CISWI units without any air 

pollution control devices, such as for units that employ 

material balance operating limits in conjunction with periodic 

stack testing to demonstrate continuous compliance.

We also determined that dry sorbent injection (or dry 

scrubbers) may be one type of additional control device that 

CISWI units may widely use to control acid gases. Commenters 

agreed with our statement and encouraged the EPA to identify 

operating parameters for dry scrubbing systems in the final 

rule. We have done so, by both defining “dry scrubber” in the 

rule, and specifying that the sorbent injection rate must be 

monitored and maintained at or above the operating rate 

established during the HCl performance test (40 CFR 60.2165 and 

40 CFR 60.2730). Furthermore, we have determined that the 

sorbent injection rate for ERUs can be adjusted to reflect 

operating loads that are less than those during the performance 
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testing. Commenters have made arguments that requiring a high 

sorbent injection rate during reduced boiler loads can lead to 

fouling and plugging issues, especially for acid gas sorbent 

injection. To address this particular concern, and to provide 

consistency with other industrial boiler rules, we are also 

providing this parametric monitoring provision for sorbent 

injection air pollution control devices. 

Also regarding monitoring, we determined after proposal 

that we had not clarified in the rule that sources opting to use 

CEMS to measure NOX, Hg or D/F were not required to monitor ACI 

rates (for Hg and D/F CEMS-equipped units) or SNCR parameter 

monitoring (for NOXCEMS-equipped units). Our intent had been to 

not require applicable control device parameter monitoring if a 

CEMS was in use for the pollutant being controlled by the 

device. Control device parameter monitoring is an acceptable and 

established method for determining continuous compliance and it 

is appropriate to require such monitoring when coupled with 

period stack testing. However, direct, continuous emission 

measurements with a CEMS are sufficient for determining 

compliance for CISWI units without requiring parametric 

monitoring. In cases where CEMS data are available to directly 

measure regulated pollutants, operating parameter data would be 

duplicative.
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7. Particulate Matter Continuous Monitoring Provisions for Large 

ERUs and Waste-burning Kilns

In today’s rule, we are finalizing monitoring requirements 

for ERUs with an annual average heat input rate greater than 250 

MMBtu/hr. As we stated in the proposal, recent EPA experience 

with the utility boiler source category has led the EPA to allow 

PM CEMS as an alternative, rather than a requirement. Industry 

commenters have maintained that there were several problems with 

implementing the monitoring requirements to demonstrate 

compliance using a PM CEMS and with the requirements to conduct 

a periodic audit of the PM CEMS in accordance with PS 11 of 

appendix B and Procedure 2 of appendix F to part 60. As we 

discuss in response to these comments later in this preamble 

(See II.E), the PM CEMS technology may not be sufficient to 

certify accurate monitor performance in the PM concentration 

range of the CISWI biomass ERU limits. Furthermore, in related 

ongoing work on the Portland cement source category, we realize 

that similar concerns regarding PM CEMS are applicable. 

Therefore, we are also removing PM CEMS (PS-11) requirements for 

waste-burning kilns, and instead, requiring PM CEMS equipment 

(i.e., PM CPMS) [A9]for these units that are used for continuous 

parametric monitoring rather than for direct measure of 

compliance with the numerical PM emissions limit, similar to 

those being required for major industrial boilers and utility 
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boilers. However, PM CEMS (PS-11), are still allowed as an 

option for coal ERUs, incinerators and small remote 

incinerators, since the emission limits for these subcategories 

do not pose the same technical concerns as for biomass ERUs and 

waste-burning kilns. To be consistent with these other rules, we 

have incorporated 30-day rolling averages to be measured with PM 

CPMS. The EPA is further requiring that a site-specific 

parametric operating limit be established during the performance 

test, that there be continuous monitoring of that parametric 

limit using a PM CPMS, that an exceedance of that site-specific 

operating limit be reported as a deviation and trigger immediate 

corrective action and a Method 5 performance test within 45 

days. 

8. Compliance Dates

At reconsideration proposal, we proposed to extend the 

compliance dates for existing units in the incinerator, ERU and 

waste-burning kiln subcategories. We are finalizing the revision 

of the effective dates for those three subcategories and, based 

on comments received during the comment period, we are also 

extending the compliance date for units in the small remote 

incinerator subcategory. The EPA proposed to amend the standards 

for CO for all subcategories of CISWI; to further subcategorize 

certain subcategories; to change several other pollutant 

standards for incinerator, ERU and waste burning kilns 
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subcategories; to change the compliance regime from CEMS-based 

to stack-test/parametric-monitoring based for certain pollutants 

and unit types; and to change the compliance calculation 

provisions for sources that are required or that elect to use 

CEMS to demonstrate continuous compliance. These proposed 

changes may occasion the need for additional time for sources to 

study the possibility of different control and monitoring 

strategies than would have been considered if we had not amended 

the 2011 CISWI rule. New compliance strategies require time to 

implement. New engineering studies are needed, potential 

suppliers identified, a new bidding/procurement process 

undertaken and the appropriate construction and operating 

permits obtained. Significant plant redesign, in the form of new 

ductwork and new fan design and changes in the main control 

equipment may be needed. See US EPA, Engineering and Economic 

Factors Affecting the Installation of Control Technologies for 

Multipollutant Strategies, October 2002. Depending on the type 

of control, this normally requires 15-27 months. Multiple 

control systems will take longer. Id. Installation of controls 

normally occurs at times of unit outages, which will likely end 

up being at differing times of the year for each of the CISWI 

subcategories. For example, for waste-burning kilns, this would 

occur during winter months (to coincide with kiln outages during 

low production seasons). However, for small remote incinerators, 
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facility retrofits would need to occur while road access to the 

site is available and climatic conditions allow for 

construction. Also, small remote incinerators have the 

additional component of having to increase the footprint of the 

site to accommodate additional space for control devices and 

waste segregation facilities. This additional permitting 

requirement and construction effort is not something other CISWI 

subcategories have to face but adds an additional consideration 

to developing a compliance strategy. In general, though, the 

differing construction constraints for the various subcategories 

of CISWI likely mean that there will be a wide variety to the 

rate of progress towards compliance for the differing CISWI 

sources. Further, commenters have argued that, due to the delay

of the final 2011 CISWI rule, uncertainty on selecting a 

compliance strategy was created, essentially putting internal 

compliance implementation activities on hold until the 

reconsideration was complete. As a result of these 

considerations, we have finalized extending compliance for all 

subcategories of CISWI. Comments on extending the compliance 

date and our responses to these comments are found in the 

“Summary of Comments and Responses to the CISWI Reconsideration” 

document in the CISWI docket.

The compliance date for existing CISWI sources subject to 

standards in this final rule is 5 years after the date of 
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publication of this final rule or 3 years after the state plan 

is approved, whichever happens earlier. This date is being 

finalized in order to provide facilities sufficient time to 

install controls or to make other compliance-related decisions. 

However, the CAA section 129(f)(2) does require that the 

promulgated standards be effective “as expeditiously as 

practicable after approval of a State plan,” so that states have 

the flexibility to determine that the standards for existing 

units within their purview may have a compliance date which is 

less than the allowable 3 years following approval of the state 

plan. For new sources, the EPA is finalizing the proposed change 

of the compliance date to 6 months after the date of publication 

of the final reconsideration rule or at startup, whichever is 

later. 

9. Definition of Waste-burning Kiln

In the December 23, 2011, reconsideration proposal, we 

proposed revisions to the definition of “waste-burning kiln” to 

indicate that the term “does not include a kiln that is feeding 

non-hazardous secondary ingredients exclusively into the cold 

end of the kiln.” In proposing this language, the EPA intended 

to codify principles set out in a previous action granting and 

denying reconsideration of the NESHAP for Portland cement kilns. 

See 76 FR 28318, 28322 (May 17, 2011); see also Memorandum 

“Revised Floors Without Kilns That Would Have Been CISWI Kilns 
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Had the Solid Waste Definition Applied” (EPA, April 25, 2011) 

(which memorandum is summarized in the May 17 Federal Register

notice). The May 17, 2011 notice and April 25, 2011, memorandum 

state in essence that combustion does not occur in any region of 

a cement kiln except the hot end and that cement kiln dust added 

to the hot end of a cement kiln also is not combusted since it 

is inorganic and essentially inert.

The language used at proposal captured some but not all of 

these principles, since it referred only to the “cold end” of a 

cement kiln, as pointed out by a number of commenters. The EPA 

is revising the definition in the final rule to accurately 

reflect the May 17 preamble and April 25 memorandum discussion 

of when combustion occurs in a cement kiln. In addition, we are 

adding the fact that combustion in a cement kiln does also take 

place in the combustion zone of a precalciner or riser duct 

burner.

One further clarification is appropriate. The May 17, 2011, 

preamble contains one reference to legitimacy criteria for 

determining when a secondary material is being recycled. 76 FR 

at 28322/1-2. The threshold issue for determining if a unit is 

subject to section 129 is whether it “combusts” solid waste 

material (see section 129 (g)(1)). For cement kilns, this 

determination does not necessarily turn on legitimacy of 

recycling, but rather on the nature of the cement kiln process. 
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Consequently, if combustion of solid waste is not occurring, a 

unit is not a CISWI, irrespective of whether or not legitimate 

recycling is occurring. 

10. Exemption for Other Solid Waste Incineration (OSWI) Units

Following publication of the December 23, 2011, 

reconsideration proposal, we realized that the CISWI rule did 

not contain any language to clarify overlap with another CAA 

section 129 regulation applicable to OSWI units. The CISWI rule 

already contains exemptions for MWCs, HMIWIs and SSIs, but 

omitted similar language for OSWI units. Therefore, in this 

final rule, we are providing language in 40 CFR 60.2020 and 

60.2555 that clarifies that incineration units that are subject 

to 40 CFR part 60 subparts EEEE or FFFF are exempt from the 

CISWI rule. 

D. Technical Corrections and Clarifications

We are also including some technical corrections and 

clarifications in the final rule, as outlined below:

Operating parameter limits during performance testing –

While we believe it is intrinsic that established operating 

parameter limits do not apply during subsequent performance 

testing since they are being confirmed or reestablished 

during the subsequent testing, we provided language in the 

proposed rule in the NSPS to clarify that they are waived 

during performance testing (40 CFR 60.2145(c)). However, we 

inadvertently omitted this clarifying language in the 

emission guidelines so we have added clarifying language in 

the final emission guidelines at 40 CFR 60.2710(c).

Bypass stacks on waste-burning kilns – While not included 

in the final rule text, we are clarifying here that the 
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definition of “bypass stack” in today’s final rule does not 

have the same meaning as an “alkali bypass” used by some 

waste-burning kilns that manufacture Portland cement.

Clarifying that, consistent with CAA section 129(f)(1), 

June 4, 2010, is the appropriate new source applicability 

date in 40 CFR 60.2015(a)(1).

Revising the title of Table 2 to subpart DDDD to clarify 

that these emission limits apply to incinerators which are 

currently subject to CISWI emission limits promulgated in 

the 2000 CISWI rule.

Clarifying that petitions for specific operating limits for 

control devices not listed in this subpart must be 

submitted to the Administrator at least 60 days before the 

performance test is scheduled to begin(40 CFR 60.2115 and 

40 CFR 60.2680).

Providing definitions of “30-day rolling average” and 

“responsible official” to clarify what is meant by these 

terms.

Adding text to the provisions for PM monitoring provisions 

for ERUs to clarify that the 250 MMBtu/hr threshold is 

based upon the average annual heat input rate, consistent 

with how this threshold is applied in the industrial boiler 

NESHAP. 

Revising the affirmative defense text to clarify that these 

provisions apply to violations of standards and to further 

clarify the reporting requirements and criteria for sources 

seeking to assert an affirmative defense (40 CFR 60.2120 

and 40 CFR 60.2685).

Revising the recordkeeping provisions in 40 CFR 60.2175(v) 

and 40 CFR 60.2740(u) to reflect the categorical non-waste 

determination provisions of 40 CFR 241.4.

Revising the electronic reporting provisions in 40 CFR 

60.2235 and 40 CFR 60.2795 to clarify the timing and 

mechanism for submitting these reports and to be consistent 

with the electronic reporting language in more recent 

rulemakings.

Revising the definition of “process change” to clarify the 

intended types of changes that would require re-testing.

Making corrections to the D/F calculation methodologies for 

toxic equivalency basis and adding calculation methodology 

provisions for D/F TMB.
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Revising the definition of “space heater” to clarify 

applicability for units that meet the requirements of 40 

CFR 279. 

E. Major Public Comments and Responses

We have included some of the major comment topics and our 

responses below in the preamble. All other comments and 

responses are provided in the “Reconsideration Response to 

Public Comments Document” in the CISWI docket.

Solid-fuel ERU Subcategorization

Comment: Several commenters support the proposed separate 

coal and biomass standards for D/Fs, CO, NOx , SO2, PM, Cd and 

Pb. However, these commenters further urge the EPA to establish 

separate standards for HCl and Hg for coal and biomass. 

Commenters state that the EPA’s recognition that design and 

operational differences between combustors designed to combust 

coal and those designed to combust biomass is evidence to 

support subcategorizing emission limits for all pollutants. One 

commenter discussed differences in biomass and coal fuel rank, 

and the significant boiler design differences in furnace height 

and volume that exist between units designed to combust 

different fuel ranks of coal-fired boiler furnaces. As an 

example, one commenter noted that a low-rank coal (high slagging 

lignite) furnace can be 1.65 times the plan area, and 1.45 times 

the furnace height, of a similar capacity furnace combusting a 

high rank coal (medium volatile bituminous). The commenter 
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stated that this large difference is even among varying grades 

of coal, with biomass units being fuels of even lower rank than 

lignite. Therefore, according to the commenter, furnace area and 

height (and hence, volume) are significantly different between 

ERUs designed to combust coal and those designed for biomass 

combustion. The commenter highlighted an analysis of their 

existing boilers to see the feasibility of substituting biomass 

for coal. The commenter’s results indicated that, due to 

fundamental design attributes of their coal-fired units, they 

could only co-fire up to 20 percent biomass in the units. The 

commenter explained that this limitation was due to design 

issues pertaining to the unit being designed for coal, such as 

superheater tube spacing, number and location of soot blowers, 

fouling characteristics of biomass ash and the impact the high 

moisture levels of biomass fuels have on fan capacity. The 

commenter stated that these findings further support that coal 

and biomass are not interchangeable within ERUs and therefore 

supports subcategorizing emission limits between the two types 

of unit. The commenter also contended that the EPA acknowledged 

significant design differences and their impacts on Hg emissions 

during development of the Utility MACT Final Rule. The commenter 

urges the EPA to take a similar approach in CISWI. One commenter 

agreed with differentiation between coal-fired and biomass ERUs 

but supported keeping solid-fuel ERUs together for purposed of 
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HCl and Hg emission limits. Another commenter argued that all of 

the EPA’s subcategories are unlawful and arbitrary, noting that 

their reasons for this belief were given in their comments on 

the 2010 proposal.

Response: Based on our proposal and follow-up comments 

summarized below, the EPA is finalizing separate limits for all 

nine pollutants for biomass and coal ERUs. We agree with 

comments concerning differences in moisture content between 

biomass and coal-fired units. We reviewed data in the CISWI 

database and see that the stack gas moisture content of coalfired ERUs is around 11.6 percent and is about 19.2 percent for 

the biomass ERUs. We have considered the technical arguments 

provided by commenters on CISWI ERUs, other technical 

differences we have previously considered in our decision to 

subcategorize ERUs and how these design differences impact 

pollutant emission characteristics of the ERU. As a result, we 

have determined that subcategorizing all nine pollutant emission 

limits between coal and biomass solid-fuel ERUs is appropriate 

for the final CISWI rule.

One commenter supported the differentiation between coal 

and biomass, but in keeping HCl and Hg limits together. However, 

for the reasons given above, we have determined that all nine 

pollutants should be subcategorized. We also note that comments 
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on subcategorization that were submitted on the 2010 proposal 

have already been responded to. 

Homogeneous Waste Definition

Comment: Several commenters contend that the proposed 

definition of “homogeneous waste” is too strict and inflexible. 

Commenters argue that traditional fuel, such as coal, would not 

even meet the definition since traditional fuels typically have 

some degree of variability of composition. 

Commenters further argue that the result of the proposed 

definition of “homogeneous waste” is contrary to Congress’ 

intent. Commenters assert that “homogeneous” should mean that 

all the materials are generated from the same type of production 

process and is material specific. Several commenters also oppose 

the additional conditions on mixtures of homogeneous wastes as 

having to be conditioned or processed. Some commenters also 

believe that multiple different homogenous wastes may be 

combusted at the same time, meaning a facility can combust 

railroad ties, traditional coal, treated seed and resonated wood 

at the same time and still qualify as burning “homogeneous 

waste.”

Response: As stated above, we are removing the proposed 

definition of homogenous waste and we are not including a 

revised definition in the final rule for the reasons discussed 
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above in section II.C of this preamble. “Summary of Significant 

Changes Since Proposal”. 

We do not believe the commenters’ suggested definitions are 

appropriate or workable and could have the unintended result of 

making almost any waste stream or combination of waste streams 

homogenous. We also believe commenters have failed to provide 

sufficient support for their claims that their proposed 

definitions are consistent with the statutory intent. We believe 

that case-by-case determinations are the appropriate approach 

given the inherent variability of waste streams. 

While we are removing the definition of homogenous waste 

from the final rule, we are retaining the requirement for 

sources to obtain a homogenous waste determination in order to 

qualify for the exemption for qualifying small energy producers 

and qualifying cogeneration facilities. We are also retaining 

the recordkeeping provisions to ensure that sources adequately 

provide and maintain evidence that they qualify for the 

exemption.

Contained Gaseous Material

Comment: Commenters support the EPA retaining the 2000 

CISWI rule’s definition of “contained gaseous material.” Some 

commenters believe that the EPA should expressly include the 

definition of “contained gaseous material” in the amendatory 

text to confirm that the definition is back in the CISWI rule. 
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Response: We disagree with commenters that state the 

definition was not in the proposed rule. The basis of the 

reconsideration proposal amendatory text was the 2000 CISWI rule 

- not the 2011 CISWI rule - because the 2011 CISWI rule had not 

been codified in the CFR pursuant to the Delay Notice. 

Therefore, by not including the amendatory instruction to delete 

the definition in the 2000 rule in the proposed reconsideration 

rule, we proposed to retain the definition as contained in the 

2000 CISWI rule. However, as explained above, due to the 

vacature of the Delay Notice, the 2011 CISWI rule is in effect 

and the definition of contained gaseous material does not appear 

in that rule. For that reason, we are including the definition 

of “contained gaseous material” found in the 2000 CISWI rule in 

today’s final rule. 

Oxygen Correction During Startup and Shutdown

Comment: Commenters generally support allowing the use of 

uncorrected CEMS data during startup and shutdown. Several 

commenters are concerned that the 4‐ hour startup and a 1-hour 

shutdown period (derived from a single coal fired unit) are not 

sufficient for all the CISWI unit types and technologies. Other 

commenters believe there should be no time limitations on 

shutdown and startups. One commenter, however, believes the 

proposed time limit is appropriate. Some commenters recommend 
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using the Boiler MACT rule approach using load to define when 

the O2corrections do not apply.

Commenters also urge the EPA to eliminate the O2correction 

for all CEM-measured emission limits, not just CO, during 

startup and shutdown periods. Commenters also support making 

this allowance available to all types of CISWI unit, not only 

ERUs. 

Response: In today’s final rule, we are retaining the 

provision that allows sources to use uncorrected CO CEMS data 

during periods of startup and shutdown. Based on comments and 

the technical justifications for allowing the use of uncorrected 

CEMS data identified during the comment period, we are expanding 

this provision to any pollutant for which continuous compliance 

is being determined using CEMS as explained above in “Section 

II.C: Summary of Significant Changes Since Proposal.”

Particulate Matter Continuous Monitoring Provisions for Large 

ERUs and Waste-burning Kilns

Comment: Several commenters supported the EPA’s proposal to 

remove requirements for PM CEMS (using PS-11) for continuous 

compliance for large ERUs and waste-burning kilns, stating that 

PM CEMS usefulness and application issues of these monitors are 

uncertain. Commenters asserted that, for biomass ERUs and 

sources with low PM concentration, PM CEMS were not adequate to 
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accurately monitor low PM concentrations. Commenters further 

contended that PM CPMS are essentially the same thing as PM 

CEMS, and that there were no clear instructions on how to 

“certify” PM CPMS, as was required in the proposed rule. 

Commenters added that they do not understand how the recording 

of hourly and 30-day rolling averages of the output from these 

monitors will be useful to demonstrate performance or evaluate 

compliance with a PM limit. One commenter suggested that the EPA 

remove the PM CPMS requirements altogether for all industrial 

boilers.

Response: We are revising the PM CEMS requirements in the 

final rule as explained above. 

In responding to this comment specifically, we believe it 

is useful to review the procedures and acceptance criteria of 

PS-11, the protocol mandated by the 2011 final CISWI rule. 

Performance Specification-11

PS-11 is structured differently than other PSs that apply 

to validating the performance of gaseous pollutant CEMS. This is 

primarily because the pollutant, PM, is defined entirely by the 

test method specified by regulation to measure it. As the 

industry commenters note, there are no independent standard 

reference materials for PM concentrations as there are for 

gaseous pollutants (e.g., NIST traceable compressed gases for 

validating SO2or NOXinstrumental measurements). The only 
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reference standard for determining the PM concentration in an 

air or stack gas sample is the reference test method. In the 

case of the CISWI final rule, the rule specifies EPA Method 5 

for measuring filterable PM concentration (e.g., in mg/dscm).

Performance Specification 11 provides procedures and 

acceptance criteria for validating the performance of several 

types of PM CEMS technologies. Although there are multiple 

instrument and data reporting operational performance checks in 

PS-11 that are similar in concept to those for gaseous pollutant 

CEMS, there is a principal PM CEMS performance requirement that 

is distinctly different. That difference is the development of a 

site-specific PM CEMS correlation or mathematical response 

curve. There are two key procedural elements to developing that 

correlation. First, PS-11 requires that the source conduct stack 

test runs using an EPA PM test method (e.g., Method 5) and 

simultaneously collect corresponding PM CEMS output data. 

Second, the source must vary the operation of the control device 

manually in order to produce a range of PM concentrations. 

Performance Specification 11, section 8.6, requires at least 

five test runs at each of three different operating conditions 

(i.e., low, mid and high PM concentrations) for a total of 15 or 

more test runs that range from 25 to 100 percent of allowable 

emissions. Then the source must use the test method data and the 

corresponding PM CEMS output data to develop an equation (i.e., 
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a calculated linear or nonlinear curve) that will be used to 

define the relationship between the PM CEMS output and the test 

method measured PM concentrations. Each site-specific 

correlation must meet several PS-11 acceptance criteria 

including limits on confidence interval and tolerance interval 

equating to ±25 percent of the applicable emissions limit.

Discussion of Technical Issues

In prior comments submitted to the EPA on the PM CEMS 

requirements for waste-burning kilns, one issue raised about 

conducting the testing to meet the PS-11 correlation development 

requirement is the impracticality of varying the emissions from 

a FF control device. Many CISWI units subject to the standards 

use FF control devices. 

We agree with commenters that there are typically few, if 

any, physical adjustments one can apply to a FF or to the wasteburning kiln process to change the outlet PM concentration 

significantly. A FF produces essentially a constant outlet 

concentration even with changes to the inlet loading or flow 

(http://www.epa.gov/ttnchie1/mkb/documents/ff-pulse.pdf). 

Although PS-11 allows some flexibility when control device

perturbations are not possible, the resulting correlation would 

apply for only the narrow range of concentrations measured 

during the testing. The result would be that the PM CEMS would 

be correlated only for a relatively small range of conditions 
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below the applicable compliance limit. This range would not 

necessarily include situations where the standard might be 

exceeded. Without the ability to calculate emissions should the 

FF performance change from initial test conditions (e.g., bag 

leaks begin to develop), such a limited correlation range would 

render the PM CEMS less reliable for calculating long term 

average concentrations or emissions rates and for verifying 

compliance. Additionally, it is difficult and resource intensive 

to modify baghouse control efficiency in a way that is 

representative of normal operations at a waste-burning kiln.

Commenters also cited problems in developing correlations 

in stack gases with variable PM constituents and physical 

characteristics when using light scatter or scintillation 

detection PM CEMS devices. As noted above and in the EPA’s 

technology background documents (e.g., 

http://www.epa.gov/ttn/emc/cem/pmcemsknowfinalrep.pdf and 

http://www.epa.gov/ttn/emc/cem/r4703-02-07.pdf), the 

correlations developed for these types of instruments are 

inherently dependent on the particle structure, size and other 

physical characteristics as well as PM mass in the exhaust gases 

for each site. Put another way, these light-based PM CEMS 

produce a signal that can vary when different fuels or raw 

materials are introduced to the kilns or ERU even when the FF 

outlet mass concentration remains unchanged. 
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To the extent that physical characteristics of the PM in 

the stack remain stable, correlations for light-based PM CEMS 

meeting PS-11 performance criteria can represent mass rates to 

the degree of accuracy required by PS-11. For example, there are 

various design structures used in some light based PM CEMS 

devices that can mitigate the effects of changes in the physical 

aspects of particles on measurement uncertainty. In addition to 

the type of light effect measured (e.g., Rayleigh or Mie 

scattering or light scintillation), the detector wavelength and 

the frequency are design factors that will affect how the PM 

CEMS responds to small changes in the physical appearance of the 

PM. 

On this point, we note that if a source owner were 

concerned about the ability of a light based PM CEMS to meet the 

requirements of PS-11 because of variable physical 

characteristics of particles in the stack, there is at least one 

other PM CEMS technology based more directly on mass measurement 

rather than on light scatter or light scintillation 

characteristics. The currently available Beta gauge technology 

does not suffer from this particular technical problem. The Beta 

attenuation PM CEMS, also called Beta gauge, extracts a sample 

for the stack gas and collects the PM on a filter tape. The 

device periodically advances the tape from the sampling mode to 

an area where the sample is exposed to Beta radiation. The 
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detector measures the amount of Beta emitted by the sample and 

that amount can be directly related to the mass of PM on the 

filter. The Beta gauge sensitivity or detection limit can be 

enhanced (i.e., lowered) with greater sample volumes produced 

from sampling intervals up to an hour or longer. 

Another PM mass detector projected for greater use as PM 

CEMS is the TEOM. Often used in measuring ambient levels of PM, 

the TEOM operates on a basic principle that can be made 

traceable to NIST laboratory standards. The TEOM can provide a 

continuous measure of PM mass in a sample extracted from the 

stack and routed to the detector. Tapered element oscillating 

microbalance based PM CEMS are not yet commercially available.

Commenters identified another factor contributing to the 

difficulty of meeting PS-11 correlation requirements for low PM 

concentrations corresponding to a low applicable emissions 

limit, as with the promulgated PM standards here for wasteburning kilns and biomass ERUs. We have recently reevaluated the 

capabilities of the EPA Method 5 for measuring low 

concentrations of PM (See the memo “Revision of Estimated Method 

5 Detection Limit” in the CISWI docket) and have determined a 

Method 5 method detection limit of approximately 2 mg/dscm for a 

1-hour test run. The uncertainty of a measurement with Method 5 

at this PM concentration would be from 50 to 100 percent (i.e., 

±1 to 2 mg/dscm). We can determine a PQL using ~3 x method 
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detection limit to reduce that Method 5 measurement uncertainty 

to ±10 to 20 percent. That means that the PQL for a 1-hour test 

run with Method 5 would be approximately 6 mg/dscm ±0.6 to 1.2 

mg/dscm.

The CISWI PM emissions limit for existing waste-burning 

kiln sources is 3.6 mg/dscm, and is 11 mg/dscm for biomass ERUs. 

The new source limits are the same for waste-burning kilns but 

are 5.1 mg/dscm for biomass ERUs. As noted above, PS-11 

specifies acceptable criteria for a correlation directly related 

to the applicable emissions limit. For a PM CEMS set up to 

measure compliance with a 3.6 mg/dscm limit, the inherent 

uncertainty associated with a 1-hour Method 5 measurement (±0.6 

to 1.2 mg/dscm) would constitute more than half of the ±25 

percent of the applicable PS-11 acceptance threshold (i.e., ±0.9 

mg/dscm) of the mid-level PS-11 correlation test (i.e., the 

correlation for the middle of the three PS-11 correlation 

points). Factoring in the inherent PM CEMS response variability 

and the uncertainty associated with the representative sampling 

(e.g., PM and flow stratification), we agree with commenters 

that trying to satisfy PS-11 at such low concentrations using 1-

hour Method 5 test runs would be problematic. This drawback 

applies regardless of the type of PM CEMS technology used.

As commenters to the Portland Cement NESHAP have noted, one 

can improve the method detection capabilities of the Method 5 or 
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other filterable PM test method by increasing sampling volume 

and run time. For example, a test run time of about 2 hours will 

improve the Method 5 PQL to about 3 mg/dscm. The measurement 

uncertainty associated with a 2-hour test run at 3 mg/dscm would 

be about ±0.3 to 0.6 mg/dscm. At this level, the uncertainty 

associated with the PM test method measurements alone would be 

about half of the correlation limit allowed in PS-11. To achieve 

a PQL of 1 mg/dscm and a measurement uncertainty of about ±0.01 

to 0.2 mg/dscm, one would need to conduct a test run of 6 hours 

or longer. As noted above, the PS-11 correlation calculations 

would also have to account for any PM CEMS analytical and 

measurement variability.

Using data from longer Method 5 test runs will improve the 

probability of a PM CEMS meeting PS-11 correlation requirements 

but, as commenters note, will also raise practicality concerns 

without completely resolving the issue. For example, the time to 

complete 15 1-hour test runs under three different emissions 

conditions may be 3 to 6 days of field work, while the time to 

complete 15 6-hour test runs under three different emissions 

conditions will require at least 2 weeks of field work in order 

to produce and maintain the operating conditions associated with 

three different emissions rates. Longer test runs lower the 

variability of Method 5 PM measurements at near detection limit 

levels from ± 50 percent to below ± 25 percent; however, the 
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variability of Method 5 results at these low levels represents a 

significantly larger portion of the ± 25 percent correlation 

requirement of PS-11 than would Method 5 data collected at 

higher PM concentrations. Method 5 measurement uncertainty 

becomes increasingly greater with lowering PM concentration and 

thus reference measurement variability hinders the PS-11 

correlation process the most for the best performing sources. 

Thus, the ultimate result might still lack certainty and would 

also pose the most difficulty and uncertainty to those sources 

with lower PM concentrations (potentially disadvantaging more 

efficient operators).

Although longer Method 5 test runs and longer beta gauge 

sampling times reduce difficulties with PS-11 correlation for a 

PM CEMS, the EPA believes that this correlation will not be 

technically achievable for a significant number of waste-burning 

kiln and biomass ERU sources, a result in part due to the Method 

5 PM emissions measurement variability at the low concentrations 

necessary to maintain compliance with the standard. The PM CEMS 

correlations then become approximations more qualitative than 

quantitative with high levels of uncertainty at low 

concentrations (i.e., the correlations do not meet PS-11 

requirements). This characteristic exists regardless of the type 

of PM CEMS technology used by the source since it involves 

variability not only of the PM CEMS but also the Method 5 test 
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data, variability of raw material and additive feeds to the 

waste-burning kiln, and the changing particle sizes, shapes, and 

density with process operations (e.g., mill on versus mill off, 

type of fuel being used in the ERU).

Making PM CEMS work at low concentrations (<10 mg/dscm) at 

waste-burning kiln and biomass ERU sources is not impossible; 

although, to expect that correlations would be achievable at all 

low emissions sources would be unrealistic. Additionally, the 

technical limitations do not mean that PM CEMS cannot be used to 

monitor for compliance. A PM CEMS that does not meet the EPA 

correlation requirements can still produce data indicative of 

trends and changes in emissions control. Particulate Matter CEMS 

technology can be effective in monitoring control device 

performance (see, e.g., 77 FR 9371 (February 16, 2012)) where 

the EPA established PM CPMS parametric operating limits for 

electric utility steam generating units).

A monitoring approach alternative to PM CEMS and PS-11 

To address technical issues associated with PM CEMS meeting 

PS-11 correlation requirements at low PM emissions 

concentrations from waste-burning kilns and biomass ERUs, the 

impracticability in perturbing FF emission rates to establish PS 

11 correlation curves, and the potentially variable PM emissions 

characteristics expected from waste-burning kilns, the EPA is 

finalizing the change of the compliance basis for the PM 
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emissions limit from PM CEMS. For monitoring continuous 

compliance, the rule requires PM CEMS equipment but, as 

explained below, that equipment would be used for continuous 

parametric monitoring rather than for direct measure of 

compliance with the numerical PM emissions limit.

Specifically, this final rule recognizes the value of PM 

monitoring technology sensitive to changes in PM emissions 

concentrations and use of such a tool to assure continued good 

operation of PM control equipment. This approach avoids the PM 

CEMS calibration (i.e., PS-11 correlation). Therefore, the EPA 

is including provisions that a site-specific parametric 

operating limit be established during the performance test, that 

there be continuous monitoring of that parametric limit using a 

PM CPMS, that an exceedance of that site-specific operating 

limit be reported as a deviation and trigger immediate 

corrective action [A10]and a Method 5 performance test within 45 

days. 

F. What other actions are we taking?

In this final action, we are denying requests for 

reconsideration on all issues contained in the petitioners’ 

requests for reconsideration that we did not include in the 

December 23, 2011, proposed rule. The issues for which we are 

denying reconsideration failed to meet the standard for 

reconsideration under CAA section 307(d)(7)(B) and we determined 
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that reconsideration was not otherwise appropriate. 

Specifically, on these issues, the petitioner has failed to show 

the following: that it was impracticable to raise their 

objections during the comment period; or that the grounds for 

their objections arose after the close of the comment period; 

and/or that their concern is of central relevance to the outcome 

of the rules. We have concluded that no clarifications to the 

underlying rules are warranted for the 19 remaining petitioners’ 

issues for the reasons set forth in the memorandum titled 

“Denied CISWI Petition Issues” found in the CISWI docket. The 

following issues are addressed in that memorandum.

Work practice standards should be used for 

startup/shutdowns and malfunctions.

Exempt or revise limits for units combusting de minimis 

amounts of waste.

Clarify applicability of CISWI standards to marine vessel 

units or units located on the outer continental shelf.

Clarify applicability to temporary or portable units.

Reduce performance testing requirements to be more 

consistent with requirements of other rules.

Reconsider elimination of provisions that allow missing 

CEMS data.

Do not include emissions data for combination boiler units.

CISWI does not satisfy CAA 112(c)(6) requirements for POM 

and PCB.

MACT floor statistical approach concerns.

MACT floor must reflect the average, the UPL is not the 

same as the average emission level.

MACT floor pollutant-by-pollutant approach concerns.

Non-detect methodology is unlawful.

Beyond-the-floor analysis is unlawful and arbitrary.
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Compliance cost and wildlife concerns for small remote 

incinerators.

“Refinery gas” definition should be included in the CISWI 

rule.

Clarify that construction and demolition wood is not a 

solid waste.

G. What are the impacts associated with the amendments?

1. What are the primary air impacts?

We have estimated the potential emissions reductions from 

existing sources that may be achieved through implementation of 

the emission limits. However, we realize that some CISWI owners 

and operators are likely to determine that alternatives to waste 

incineration are viable, such as further waste segregation or 

sending the waste to a landfill or MWC, if available. In fact, 

sources operating incinerators, where energy recovery is not a 

goal, may find it cost effective to discontinue use of their 

CISWI unit altogether. Therefore, we have estimated emissions 

reductions attributable to existing sources complying with the 

limits, as well as those reductions that would occur if the 

facilities with incinerators and small, remote incinerators 

decide to discontinue the use of their CISWI unit and use 

alternative waste disposal options. 

For units combusting wastes for energy production, such as 

ERUs and waste-burning kilns, the decision to combust or not to 

combust waste will depend on several factors. One factor is the 

cost to replace the energy provided by the waste material with a 
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traditional fuel, such as natural gas. Another factor would be 

whether the owner or operator is purchasing the waste or 

obtaining it at no cost from other generators, or if they are 

generating the waste on-site and will have to dispose of the 

materials in another fashion, such as landfills. Lastly, these 

units would have to compare the control requirements needed to 

meet the CISWI emission limits with those needed if they stop 

burning solid waste and are then subject to a NESHAP instead. As 

mentioned before, we have attempted to align the monitoring 

requirements for similar non-waste-burning sources as closely as 

possible in an effort to make them consistent and to help 

sources make the cross-walk between waste and non-waste 

regulatory requirements as simple as possible.

The emissions reductions that would be achieved under this 

final rule using the definition of solid waste under RCRA and 

the proposed CISWI emission limits are presented in Table 5 of 

this preamble.

Table 5. Emissions Reductions for MACT Compliance and 

Alternative Disposal Options for Existing CISWI Using the 

Emission Limits 

Pollutant

Reductions 

achieved through 

meeting MACT 

(ton/yr)

Reductions achieved 

assuming incinerators and 

small, remote 

incinerators use 

alternative disposal 

(ton/yr)a

HCl 772.2 784.3

CO 20,092 20,057

Pb 2.60 2.61
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Pollutant

Reductions 

achieved through 

meeting MACT 

(ton/yr)

Reductions achieved 

assuming incinerators and 

small, remote 

incinerators use 

alternative disposal 

(ton/yr)a

Cd 1.807 1.809

Hg 0.341 0.344

PM (filterable) 2,409 2,412

dioxin, furans 0.000062 0.000064

NOx 5,292 5,399

SO2 6,211 6,262

Total 34,781 34,919

a The estimated emission reduction does not account for any 

secondary impacts associated with alternate disposal of diverted 

ERU fuel.

The EPA expects that many existing CISWI owners and 

operators may find that alternate disposal options are 

preferable to complying with the standards for the incinerator 

and small, remote incinerator subcategories. Our experience with 

regulations for MWC, HMIWI and, in fact, CISWI, has shown that 

negative growth in the source category historically occurs upon

implementation of CAA section 129 standards. Since CISWI rules 

were promulgated in 2000 and have been in effect for existing 

sources since 2005, many existing units have closed. At 

promulgation in 2000, the EPA estimated 122 units in the CISWI 

population. In comparison, the incinerator subcategory in this 

rule, which contains any such units subject to the 2000 CISWI 

rule, has 27 units. The EPA is not aware of any construction of 

new units since 2000 [A11]so we do not believe there are any units 

that are currently subject to the 2000 CISWI NSPS. The revised 
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CISWI rule is more stringent so we expect this trend to 

continue. However, the EPA does recognize that some facilities 

may opt to replace aging incinerator units with new units where 

it is cost effective or alternative disposal options are not 

feasible, as may be the case with some incinerators, or in very 

remote locations. We estimate that there could be one new 

incineration unit within the next 5 years following this final 

rule, and possibly five new small remote incinerators within 

that time. [A12]In these cases, we have developed model CISWI unit 

emissions reduction estimates for these subcategories using the 

current existing unit baseline, based on average emission 

concentration values and sizes from our current inventory and 

the new source emission limits. Table 6 of this preamble 

presents the model plant emissions reductions that are expected 

for new sources. 

Table 6. Emissions Reductions on a Model Plant Basis

Pollutant

Emission reduction for CISWI Subcategory Model 

Units (tpy unless otherwise noted)

Incinerator

Small, remote 

incinerator

HCl 3.67 0.0

CO 1.23 0.25

Pb 0.83 0.0039

Cd 0.022 0.0

Hg 0.004 0.000012

PM 

(filterable)

148 0.5

D/F (total 

mass)a

0.0018 0.0

NOx

16.3 0.15
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Pollutant

Emission reduction for CISWI Subcategory Model 

Units (tpy unless otherwise noted)

Incinerator

Small, remote 

incinerator

SO2

7.6 0.15

Total 178 0.90

a D/F estimates are given in lb/yr.

We do not anticipate that any new energy recovery or wasteburning kiln units will be constructed and will instead use 

alternative waste disposal methods or alternative fuels that 

will not subject them to the CISWI rule. For example, whole 

tires obtained from approved tire management programs and tirederived fuel from which the metal has been removed is not 

considered solid waste under the definition of solid waste. 

Consequently, new cement kiln owners will assess their 

regulatory requirements under CISWI for burning whole tires or 

tire-derived fuel that does not have metals removed against the 

costs associated with removing the metal or obtaining tires from 

an approved source and complying with the applicable NESHAP 

instead of the CISWI rule. Our research suggests that metal 

removal is routinely practiced and that several state waste tire 

management programs are already in place and would most likely 

be a viable option for new kiln owners so that they would not be 

subject to the CISWI regulations. Indeed, we expect that all 

existing cement kilns that are classified as being waste-burning 

solely due to whole tires will, by the effective date for the 
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CISWI standards, find a way to obtain their tires through an 

approved tire management plan. Likewise, new sources could 

engineer their process to minimize waste generation in the first 

place or to separate wastes so that the materials sent to a 

combustion unit would not meet the definition of solid waste to 

begin with. For waste that is generated, our cost analyses have 

found that alternative waste disposal is generally available and 

less expensive.

2. What are the water and solid waste impacts?

In our analysis, we have selected the lowest cost 

alternative (i.e., compliance or alternative disposal) for each 

facility. We anticipate affected sources will need to apply 

additional controls to meet the emission limits. These controls 

may use water, such as wet scrubbers, which would need to be 

treated. We estimate an annual requirement of 71 billion gallons 

per year of additional water would be required as a result of 

operating additional controls or increased sorbent use.

Likewise, the addition of PM controls or improvements to 

controls already in place will increase the amount of 

particulate collected that will require disposal. Furthermore, 

ACI may be used by some sources, which will result in additional 

solid waste needing disposal. The annual amounts of solid waste 

that would require disposal are anticipated to be approximately 

26,200 tpy from PM capture and 14,300 tpy from ACI. 
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Perhaps the largest impact on solid waste would come from 

owners and operators who decide to discontinue the use of their 

CISWI unit and instead send waste to the landfill or MWC for 

disposal. Based on tipping fees and availability, we would 

expect most, if not all, of this diverted waste to be sent to a 

local landfill. As we discuss above, it may be that a good 

portion of the incinerators would determine that alternative 

disposal is a better choice than compliance with the standards. 

We estimate that approximately 110,600 tpy of waste would be 

diverted to a landfill. 

For new CISWI units, we estimate an annual requirement of 

6.8 million gallons per year of additional water would be 

required as a result of operating additional controls. The 

annual amounts of solid waste that would require disposal are 

anticipated to be approximately 152 tpy from PM capture and 12 

tpy from ACI.

3. What are the energy impacts?

The energy impacts associated with meeting the emission 

limits would consist primarily of additional electricity needs 

to run added or improved air pollution control devices. For 

example, increased scrubber pump horsepower may cause slight 

increases in electricity consumption and sorbent injection 

controls would likewise require electricity to power pumps and 

motors. In our analysis, we have selected the lowest cost 
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alternative (i.e., compliance or alternative disposal) for each 

facility. By our estimate, we anticipate that an additional 

230,500 MW-hours per year would be required for the additional 

and improved control devices.

As discussed earlier, there could be instances where owners 

and operators of ERUs and waste-burning kilns decide to cease 

burning waste materials. In these cases, the energy provided by 

the burning of waste would need to be replaced with a 

traditional fuel, such as natural gas. Assuming an estimate that 

50 percent of the energy input to ERUs and kilns are from waste 

materials, an estimate of the energy that would be replaced with 

a traditional fuel if all existing units stopped burning waste 

materials, is approximately 56 TBtu/yr. 

For new CISWI units, we anticipate that 511 MW-hours per 

year would be required for additional and improved control 

devices. Since we do not anticipate any new energy recovery or 

waste-burning kiln units to be constructed, there would be no 

additional estimate for energy that would be replaced with a 

traditional fuel.

4. What are the secondary air impacts?

For CISWI units adding controls to meet the emission 

limits, we anticipate minor secondary air impacts. The 

combustion of fuel needed to generate additional electricity and 

to operate RTO controls would yield slight increases in 
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emissions, including NOx, CO, PM and SO2 and an increase in CO2

emissions. Since NOx and SO2 are covered by capped emissions 

trading programs, and methodological limitations prevent us from 

quantifying the change in CO and PM, we do not estimate an 

increase in secondary air impacts for this rule from additional 

electricity demand.

We believe it likely that the incinerators may elect to 

discontinue the use of their CISWI unit and send the waste to 

the landfill or other disposal means. As we discussed in the 

solid waste impacts above, this could result in approximately 

11,600 tpy of waste going to landfills. By using the EPA’s 

Landfill Gas Estimation Model, we estimate that, over the 20-

year expected life of a CISWI unit, the resulting methane 

generated by a landfill receiving the waste would be about 

96,400 tons. If this landfill gas were combusted in a flare, 

assuming typical flare emission factors and landfill gas 

chlorine, Hg and sulfur concentrations, the following emissions 

would be expected: 20 tons of PM; 8 tons of HCl; 16 tons of SO2; 

890 tons of CO; 46 tons of NOx; and 1.4 lbs of Hg. 

Similar to existing units, we anticipate minor secondary 

air impacts for new CISWI units adding controls as discussed 

above.

5. What are the cost and economic impacts?
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We have estimated compliance costs for all existing units 

to add the necessary controls and monitoring equipment, and to 

implement the inspections, recordkeeping and reporting 

requirements to comply with the final CISWI standards. We have 

also analyzed the costs of alternative disposal for the 

subcategories that may have alternative options to burning 

waste, specifically for the incinerators and the small, remote 

incinerators that may have an alternative to incineration. In 

our analysis, we have selected the lowest cost alternative 

(i.e., compliance or alternative disposal) for each facility. 

Based on this analysis, we anticipate an overall total capital 

investment of $816 million with an associated total annual cost 

of $271 million ($2008). For comparison, the 2011 final rule, 

estimated an overall total capital investment of $652 million 

with an associated total annual cost of $232 million ($2008). 

The annualized cost of today’s final rule are approximately 17% 

higher than those of the final 2011 CISWI rule. The changes in 

cost result from revising the inventories of the ERUs, wasteburning kilns and small remote incinerators as discussed in 

Section II.C. of this preamble: “Summary of Significant Changes 

Since Proposal.”

Under the rule, the EPA’s economic model suggests the 

average national market-level variables (prices, production-
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levels, consumption, international trade) will not change 

significantly (e.g., are less than 0.001 percent).

The EPA performed a screening analysis for impacts on small 

entities by comparing compliance costs to sales/revenues (e.g., 

sales and revenue tests). The EPA’s analysis found the tests 

were below 3 percent for four of the five small entities 

included in the screening analysis.

In addition to estimating this rule’s social costs and 

benefits, the EPA has estimated the employment impacts of the 

final rule. We expect that the rule’s direct impact on 

employment will be small. For the reconsideration final, the 

estimated employment changes range between −400 to +900 

employees, with a central estimate of +200.

We have not quantified the rule’s indirect or induced 

impacts. For further explanation and discussion of our analysis, 

see the introductory memo and Section 3 of the RIA.

For new CISWI units, we have estimated compliance costs for 

units coming online in the next 5 years. This analysis is based 

on the assumption that one new incinerator will come online over 

5 years and one new small, remote incinerator will come online 

each year over the next 5 years. Additionally, it was assumed 

that each model unit will add the necessary controls, monitoring 

equipment, inspections, recordkeeping and reporting requirements 

to comply with NSPS limits. Based on our analysis, we anticipate 
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an overall total capital investment of $9.7 million over 5 years 

with an associated total annual cost (for 2015) of $2.9 million.

6. What are the benefits?

We estimate the monetized benefits of this regulatory action 

to be $420 million to $1.0 billion (2008$), 3 percent discount 

rate) in the implementation year (2015). The monetized benefits 

of the regulatory action at a 7 percent discount rate are $390 

million to $940 million (2008$). Using alternate relationships 

between PM2.5 and premature mortality supplied by experts, 

higher and lower benefits estimates are plausible but most of 

the expert-based estimates fall between these two estimates.4

Since the reconsideration proposal, we have updated the 

epidemiology studies used to calculate mortality and morbidity 

benefits in the PM NAAQS proposal RIA (U.S. EPA, 2012).5 If we 

were to incorporate these updates, the monetized benefits would 

likely decrease by less than 4 [A13]percent. More information on 

these updates can be found in the PM NAAQS proposal RIA .A 

summary of the monetized benefits estimates at discount rates of 

3 percent and 7 percent is in Table 7 of this preamble. 

 

4 Roman, et al., 2008. Expert Judgment Assessment of the Mortality Impact of 

Changes in Ambient Fine Particulate Matter in the U.S. Environ. Sci. 

Technol., 42, 7, 2268 – 2274.

5 U.S. Environmental Protection Agency (U.S. EPA). 2012. Regulatory Impact 

Analysis for the Proposed Revisions to the National Ambient Air Quality 

Standards for Particulate Matter. EPA-452/R-12-003. Office of Air Quality 

Planning and Standards, Health and Environmental Impacts Division. June. 

Available at 

http://www.epa.gov/ttnecas1/regdata/RIAs/PMRIACombinedFile_Bookmarked.pdf.
Page 100 of 319

Table 7. Summary of the Monetized Benefits Estimates For the 

CISWI NSPS and EG in 2015 (Millions of 2008$)a,b

Pollutant

Estimated Emission 

Reductions

(tpy)

Total Monetized 

Benefits

(3% Discount 

Rate)

Total Monetized 

Benefits

(7% Discount 

Rate)

PM2.5 941 $210 to $520 $190 to $470

PM2.5 Precursors

SO2 6,262 $180 to $450 $170 to $410

NOx 5,399 $26 to $64 $24 to $58

Total $420 to $1,000 $390 to $940

a All estimates are for the implementation year (2015) and are rounded to two 

significant figures so numbers may not sum across rows. All fine particles 

are assumed to have equivalent health effects but the benefit-per-ton 

estimates vary between precursors because each ton of precursor reduced has a 

different propensity to form PM

2.5

. Benefits from reducing HAP are not 

included. 

These benefits estimates represent the total monetized 

human health benefits for populations exposed to less PM2.5 in 

2015 from controls installed to reduce air pollutants in order 

to meet these standards. To estimate human health benefits of 

this rule, the EPA used benefit-per-ton factors to quantify the 

changes in PM2.5-related health impacts and monetized benefits 

based on changes in SO2and NOx emissions. These estimates are 

calculated as the sum of the monetized value of avoided 

premature mortality and morbidity associated with reducing a ton 

of PM2.5 and PM2.5 precursor emissions. To estimate human health 

benefits derived from reducing PM2.5 and PM2.5 precursor 
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emissions, we used the general approach and methodology laid out 

in Fann, Fulcher, and Hubbell (2009).6

To generate the benefit-per-ton estimates, we used a model 

to convert emissions of direct PM2.5 and PM2.5 precursors into 

changes in ambient PM2.5 levels and another model to estimate 

the changes in human health associated with that change in air 

quality. Finally, the monetized health benefits were divided by 

the emission reductions to create the benefit-per-ton estimates. 

These models assume that all fine particles, regardless of 

their chemical composition, are equally potent in causing 

premature mortality because the scientific evidence is not yet 

sufficient to support the development of differential effects 

estimates by particle type. Directly emitted PM2.5, SO2 and NOx

are the primary precursors affected by this rule. Even though we 

assume that all fine particles have equivalent health effects, 

the benefit-per-ton estimates vary between precursors depending 

on the location and magnitude of their impact on PM2.5 levels, 

which drive population exposure. For example, SO2has a lower 

benefit-per-ton estimate than direct PM2.5 because it does not 

form as much PM2.5, thus, the exposure would be lower and the 

monetized health benefits would be lower. 

 

6 Fann, N., C.M. Fulcher, B.J. Hubbell. 2009. “The influence of location, 

source, and emission type in estimates of the human health benefits of 

reducing a ton of air pollution.” Air Qual Atmos Health (2009) 2:169–176.
Page 102 of 319

It is important to note that the magnitude of the PM2.5

benefits is largely driven by the concentration response 

function for premature mortality. Experts have advised the EPA 

to consider a variety of assumptions, including estimates based 

on both empirical (epidemiological) studies and judgments 

elicited from scientific experts, to characterize the 

uncertainty in the relationship between PM2.5 concentrations and 

premature mortality. For this rule, we cite two key empirical 

studies, the American Cancer Society cohort study7 and the 

extended Six Cities cohort study.8 In the RIA for this rule, 

which is available in the docket, we also include benefits 

estimates derived from expert judgments and other assumptions.

The EPA strives to use the best available science to 

support our benefits analyses. We recognize that interpretation 

of the science regarding air pollution and health is dynamic and 

evolving. After reviewing the scientific literature and recent 

scientific advice, we have determined that the no-threshold 

model is the most appropriate model for assessing the mortality 

benefits associated with reducing PM2.5 exposure. Consistent 

with this recent advice, we are replacing the previous threshold 

 

7 Pope, et al., 2002. “Lung Cancer, Cardiopulmonary Mortality, and Long-term 

Exposure to Fine Particulate Air Pollution.” Journal of the American Medical 

Association 287:1132-1141

8 Laden, et al., 2006. “Reduction in Fine Particulate Air Pollution and 

Mortality.” American Journal of Respiratory and Critical Care Medicine. 173: 

667-672
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sensitivity analysis with a new “LML” assessment. While a LML 

assessment provides some insight into the level of uncertainty 

in the estimated PM mortality benefits, the EPA does not view 

the LML as a threshold and continues to quantify PM-related 

mortality impacts using a full range of modeled air quality 

concentrations. 

Most of the estimated PM-related benefits in this rule 

would accrue to populations exposed to higher levels of PM2.5.

Using the Pope, et al., (2002) study, 85 percent of the 

population is exposed at or above the LML of 7.5 μg/m3. Using 

the Laden, et al., (2006) study, 40 percent of the population is 

exposed above the LML of 10 μg/m3. It is important to emphasize 

that we have high confidence in PM2.5-related effects down to 

the lowest LML of the major cohort studies. This fact is 

important, because as we estimate PM-related mortality among 

populations exposed to levels of PM2.5 that are successively 

lower, our confidence in the results diminishes. However, our 

analysis shows that the great majority of the impacts occur at 

higher exposures. 

Every benefit analysis examining the potential effects of a 

change in environmental protection requirements is limited, to 

some extent, by data gaps, model capabilities (such as 

geographic coverage) and uncertainties in the underlying 
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scientific and economic studies used to configure the benefit 

and cost models. Despite these uncertainties, we believe the 

benefit analysis for this rule provides a reasonable indication 

of the expected health benefits of the rulemaking under a set of 

reasonable assumptions. This analysis does not include the type 

of detailed uncertainty assessment found in the 2006 PM2.5 NAAQS 

RIA because we lack the necessary air quality input and 

monitoring data to run the benefits model. In addition, we have 

not conducted any air quality modeling for this rule. The 2006 

PM2.5 NAAQS benefits analysis9 provides an indication of the 

sensitivity of our results to various assumptions. 

It should be emphasized that the monetized benefits 

estimates provided above do not include benefits from several 

important benefit categories, including reducing other air 

pollutants, ecosystem effects and visibility impairment. The 

benefits from reducing HAP have not been monetized in this 

analysis, including reducing 20,000 tons of carbon monoxide, 780 

tons of HCl, 2.6 tons of lead, 1.8 tons of cadmium, 690 pounds 

of mercury, and 58 grams of total D/F each year. Although we do 

not have sufficient information or modeling available to provide 

monetized estimates for this rulemaking, we include a 

qualitative assessment of the health effects of these air 

 

9 U.S. Environmental Protection Agency, 2006. Final Regulatory Impact 

Analysis: PM2.5 NAAQS. Prepared by Office of Air and Radiation. October. 

Available on the Internet at http://www.epa.gov/ttn/ecas/ria.html
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pollutants in the RIA for this rule, which is available in the 

docket.

For more information on the benefits analysis, please refer 

to the RIA for this rulemaking, which is available in the 

docket.

III. NHSM Final Revisions

A. Statutory Authority

The EPA is promulgating these regulations under the 

authority of sections 2002(a)(1) and 1004(27) of the RCRA, as 

amended, 42 U.S.C. 6912(a)(1) and 6903(27). Section 129(a)(1)(D) 

of the CAA ((42 U.S.C. 7429) directs the EPA to establish 

standards for CISWIs, which burn solid waste. Section 129(g)(6) 

of the CAA provides that the term “solid waste” is to be 

established by the EPA under RCRA. Section 2002(a)(1) of RCRA 

authorizes the agency to promulgate regulations as are necessary 

to carry out its functions under the Act. The statutory 

definition of “solid waste” is provided in RCRA section 

1004(27).

B. NHSM Rule History

The agency first solicited comments on how the RCRA 

definition of solid waste should apply to NHSMs used as fuels or 

ingredients in combustion units in an ANPRM, which was published 

in the Federal Register on January 2, 2009 (74 FR 41). We then 
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published a NHSM proposed rule on June 4, 2010 (75 FR 31844), 

which the EPA issued in final form on March 21, 2011 (76 FR 

15456). The March 2011, NHSM final rule codified the standards 

and procedures for identifying which non-hazardous secondary 

materials are “solid waste” when used as fuels or ingredients in 

combustion units.

In October 2011, the agency announced it would be 

initiating new rulemaking proceedings to revise certain aspects 

of the NHSM rule.10 On December 23, 2011, we then published a 

proposed rule, which addressed specific targeted amendments and 

clarifications to the part 241 regulations (76 FR 80452). These 

proposed revisions and clarifications were limited to certain 

issues on which the agency had received new information, as well 

as targeted revisions that the agency believed were appropriate 

in order to allow implementation of the rule as the EPA 

originally intended.11 As stated throughout the preamble to the 

proposed rule, the agency was not reopening the entire NHSM rule 

for reconsideration and would not respond to comments directed 

toward rule provisions that were not specifically identified in 

 

10 See October 14, 2011, Letter from Administrator Lisa P. Jackson to Senator 

Olympia Snowe. A copy of this letter has been placed in the docket for 

today’s rule (EPA-HQ-RCRA-2008-1873).

11 For more information regarding the intent of the December 23, 2011, 

proposed rule, see 76 FR 80469. For more information regarding the scope of 

the proposed rule, see 76 FR 80470-80474.
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this proposal.12 Therefore, any comments that were submitted 

outside the scope of the proposal, or for which the EPA did not 

solicit comment, are not addressed in this final rule, or in the 

Response to Comments document that has been prepared for this 

final rule.

C. Introduction — Summary of Regulations Being Finalized

In today’s rule, the EPA is finalizing certain amendments 

and clarifications to the 40 CFR part 241 regulations on which 

we have received new information, as well as specific targeted 

revisions that are appropriate in order to allow implementation 

of the rule as the EPA originally intended. The regulations 

being issued today are summarized below. The intent of this 

summary is to give a brief overview of the revised part 241 

regulations. More detailed discussions, including the agency’s 

responses to comments received on the proposed rule and its 

rationale for decisions being made in this final action, are 

included in section III.D of this preamble. In addition, in an 

effort to aid the regulated community, the EPA is including in 

 

12 For example, see 76 FR 80470: “The EPA is soliciting comment only on these 

targeted changes and is not reopening any other issues in the final NHSM 

rule. Comments that go beyond the scope of this narrow RCRA rulemaking will 

not be addressed by the Agency when it finalizes today’s proposed rule.” See 

also 76 FR 80474 “As noted above, the intent of this proposal is to identify 

certain specific aspects of the rule which EPA is reconsidering and on which 

it is soliciting public comment. The Agency is not reopening the entire rule 

for reconsideration and will not respond to comments directed toward rule 

provisions that are not specifically identified in this proposal.” and 76 FR 

80482 “The Agency is not considering any change to the self-implementing, 

mandatory nature of the §241.3 standards for individual facilities and will 

not respond to any comments on this topic.”.
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the docket for today’s rule an informational redline/strikeout 

version that identifies the specific changes to the regulatory 

text, as compared to the March 2011, final rule.13 

1. Revised Definitions

In today’s rule, the EPA is finalizing revisions to the 

three definitions discussed in the proposed rule: (1) “clean 

cellulosic biomass,” (2) “contaminants,” and (3) “established 

tire collection programs.” In addition, based on comments 

received on the proposed rule, the agency is also finalizing a 

revised definition of “resinated wood.” These revised 

definitions will be codified in 40 CFR 241.2. 

a. Clean Cellulosic Biomass

In today’s action, the EPA is issuing a revised definition 

of “clean cellulosic biomass” that: (1) makes clear that the 

list of biomass materials are examples within the definition and 

is not intended to be an exhaustive list; and (2) provides a 

more comprehensive list of clean cellulosic biomass to guide the 

regulated community. These revisions do not change the agency’s 

intent under the March 2011 final rule, but identify additional 

materials that are “clean cellulosic biomass,” and, thus, are 

traditional fuels under these regulations. A discussion of 

relevant comments regarding the definition of clean cellulosic 

 

13 This document has been titled, “NHSM 2012 Final Rule Regulation Changes” 

and is placed in Docket No: EPA-HQ-RCRA-2008-0329.
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biomass, as well as our rationale for making these 

determinations, can be found in section III.D.1.a of this 

preamble.

b. Contaminants

In today’s action, the EPA is issuing a final definition of 

“contaminants” to clarify what constituents will be considered 

contaminants for the purposes of the contaminant legitimacy 

criterion. Revisions include: (1) the replacement of a reference 

to “any constituent that will result in emissions” with a 

specific list of constituents to be considered as contaminants 

based on their status as a precursor to air emissions; (2) the 

removal from the definition of specific CAA section 112(b) and 

129(a)(4) pollutants that are not expected to be found in any 

NHSM or are adequately covered elsewhere in the definition; and 

(3) the removal of the phrase “including those constituents that 

could generate products of incomplete combustion” from the 

definition. A discussion of relevant comments regarding the 

contaminants definition, as well as our rationale for making 

these determinations, can be found in section III.D.1.b of this 

preamble.

c. Established Tire Collection Programs

In today’s action, the EPA is finalizing a revised 

definition of “established tire collection program” in order to 

account for “off-specification” (including factory scrap) tires 
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that are contractually arranged to be collected, managed and 

transported between a tire manufacturer (including retailers or 

other parties involved in the distribution and sale of new 

tires) and a combustor, which is analogous to how scrap tires 

removed from vehicles are managed. The off-specification tires 

are not removed from vehicles14 and are handled under contractual 

arrangements which ensure they are not discarded. A description 

of how the changes to the definition accommodate the management 

of off-specification tires can be found in section III.D.1.c of 

this preamble. In addition to the proposed changes, we are 

revising the definition to specifically include tires that were 

not abandoned and were received from the general public at tire 

collection program events. A discussion of relevant comments 

regarding the definition, as well as our rationale for making 

this determination, can be found in section III.D.1.c of this 

preamble. 

d. Resinated Wood

In today’s action, the EPA is issuing a revised definition 

of “resinated wood” that includes additional materials in order 

to be more representative of the universe of resinated wood 

residuals that are currently used as fuels throughout the wood 

product manufacturing process. Revisions include: (1) replacing 

the phrase “containing resin adhesives” with the phrase, 

 

14 “Removal from vehicles” had been a component of the definition.
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“containing binders and adhesives,” and (2) specifically 

including “off-specification resinated wood products that do not 

meet a manufacturing quality or standard” within this 

definition. A discussion of relevant comments regarding the 

resinated wood definition, as well as our rationale for making 

this determination, can be found in section III.D.3.b of this 

preamble.

2. Contaminant Legitimacy Criterion for NHSM Used as Fuels

In today’s action, the EPA is issuing in final form a 

revised contaminant legitimacy criterion for NHSMs used as fuels 

to provide additional details on how contaminant comparisons 

between NHSMs and traditional fuels may be made. Revisions 

include: (1) the ability to compare groups of contaminants where 

technically reasonable; (2) the clarification that “designed to 

burn” means can burn or does burn, and not necessarily permitted 

to burn; (3) the ability to use traditional fuel data from 

national surveys and other sources beyond a facility’s current 

fuel supplier; and (4) the ability to use ranges of traditional 

fuel contaminant levels when making contaminant comparisons, 

provided the variability of NHSM contaminant levels is also 

considered. A discussion of relevant comments regarding the 

contaminant legitimacy criterion for NHSMs used as fuels, as 

well as our rational for making these determinations, can be 

found in section III.D.2 of this preamble. 
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3. Categorical Non-Waste Determinations for Specific NHSM Used 

as Fuels

In today’s final rule, the agency is codifying 

determinations that certain NHSMs are non-wastes when used as 

fuels. Based on all available information, the EPA has 

determined that the following NHSMs are categorically not a 

solid waste when burned as a fuel in combustion units: (1) scrap 

tires that are not discarded and are managed under the oversight 

of established tire collection programs, including tires removed 

from vehicles and off-specification tires; (2) resinated wood; 

(3) coal refuse that has been recovered from legacy piles and 

processed in the same manner as currently-generated coal refuse; 

and (4) dewatered pulp and paper sludges that are not discarded 

and are generated and burned on-site by pulp and paper mills 

that burn a significant portion of such materials where such 

dewatered residuals are managed in a manner that preserves the 

meaningful heating value of the materials.

a. Scrap Tires

In today’s action, the agency is listing scrap tires that 

are not discarded and are managed under the oversight of 

established tire collection programs, including tires removed 

from vehicles and off-specification tires (including factory 

scraps), to the categorical list of non-waste fuels (see 40 CFR 

241.4(a)(1)) as proposed. Based on this categorical non-waste 
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determination, facilities burning the scrap tires that qualify 

for the provision will not need to demonstrate that this NHSM 

meets the legitimacy criteria on a site-by-site basis. Further, 

the addition to the new categorical non-waste provision at 40 

CFR 241.4(a)(1) eliminated the need for the previous scrap tire 

provision at 40 CFR 241.3(b)(2)(i),15 which has been removed and 

reserved in today’s final rule. A discussion of relevant 

comments regarding the scrap tire provision, as well as our 

rationale for making this determination, can be found in section 

III.D.3.a of this preamble.

b. Resinated Wood

In today’s action, the agency is listing resinated wood as 

a non-waste fuel in 40 CFR 241.4(a)(2), as proposed. The EPA has 

evaluated resinated wood and, based on all available 

information, including consideration of the legitimacy criteria, 

as well as other relevant factors, has determined that resinated 

wood is not a solid waste when used as a fuel. Based on this 

categorical non-waste determination, facilities burning 

resinated wood residuals as a fuel will not need to demonstrate 

 

15 The scrap tire provision in the 2011 NHSM final rule is now removed and the 

section reserved in today’s final rule: “(b) The following non-hazardous 

secondary materials are not solid wastes when combusted:

(2) The following non-hazardous secondary materials that have not been 

discarded and meet the legitimacy criteria specified in paragraph (d)(1) of 

this section when used in a combustion unit (by the generator or outside the 

control of the generator):

(i) Scrap tires used in a combustion unit that are removed from vehicles and 

managed under the oversight of established tire collection programs.”
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that this NHSM meets the legitimacy criteria on a site-by-site 

basis.

Further, the addition of this categorical non-waste 

determination (40 CFR 241.4(a)(2)) eliminated the need for the 

previous resinated wood provision at 40 CFR 241.3(b)(2)(ii),16

which has been removed and reserved in today’s final rule. A 

discussion of relevant comments regarding the categorical nonwaste determination for resinated wood, as well as our rationale 

for making this determination, can be found in section III.D.3.b 

of this preamble.

c. Coal Refuse

In today’s action, the agency has determined that coal 

refuse that has been recovered from legacy piles and processed 

in the same manner as currently-generated coal refuse, is a nonwaste fuel in 40 CFR 241.4(a)(3). This determination is based on 

the fact that: (1)legacy coal refuse processed in the same 

manner as currently-generated coal refuse meets the definition 

of processing (as codified in 40 CFR 241.2); and (2)the EPA’s 

assessment that such materials meet the legitimacy criteria for 

 

16 The resinated wood provision in the 2011 NHSM final rule is now removed and 

the section reserved in today’s final rule: “(b) The following non-hazardous 

secondary materials are not solid wastes when combusted:

(2) The following non-hazardous secondary materials that have not been 

discarded and meet the legitimacy criteria specified in paragraph (d)(1) of 

this section when used in a combustion unit (by the generator or outside the 

control of the generator):

(ii) Resinated wood used in a combustion unit.”
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fuels (as codified in 40 CFR 241.3(d)(1)) when compared to 

currently-generated coal refuse, which the agency considers to 

be within the definition of a traditional fuel (as codified in 

40 CFR 241.2). Based on this categorical non-waste 

determination, facilities burning these materials as a fuel will 

not need to demonstrate that this NHSM meets the legitimacy 

criteria on a site-by-site basis. A discussion of relevant 

comments regarding the categorical non-waste determination for 

coal refuse that is recovered from legacy piles and processed, 

as well as our rationale for making this determination, can be 

found in section III.D.5.b of this preamble.

d. Pulp and Paper Sludge

In today’s action, the EPA has determined that dewatered 

pulp and paper sludges that are not discarded and are generated 

and burned on-site by pulp and paper mills that burn a 

significant portion of such materials where such dewatered 

residuals are managed in a manner that preserves the meaningful 

heating value of the materials are non-waste fuels in 40 CFR 

241.4(a)(4). This determination for pulp and paper sludge as a 

categorical non-waste represents the agency’s finding, after 

balancing the regulatory legitimacy criteria with other relevant 

factors, that the burning of this material is an integral part 

of facility operations, and as described in the categorical 

listing is for energy recovery and not discard. Based on this 
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categorical non-waste determination, facilities meeting the 

description of this determination and burning these materials as 

a fuel will not need to demonstrate that this NHSM meets the 

legitimacy criteria on a site-by-site basis. A discussion of 

relevant comments regarding the categorical non-waste 

determination for pulp and paper sludges, as well as our 

rationale for making this determination, can be found in section 

III.D.5.a of this preamble.

4. Rulemaking Petition Process for Other Categorical Non-Waste 

Determinations (40 CFR 241.4(b))

In today’s final rule, the agency is finalizing a 

rulemaking petition process that provides persons with an 

opportunity to submit a rulemaking petition to the 

Administrator, seeking a categorical determination for 

additional NHSMs to be listed in 40 CFR 241.4(a) as non-waste 

fuels. The process for submitting a rulemaking petition to the 

agency, as well as the factors a successful application must 

include, is listed in 40 CFR 241.4(b). A discussion of relevant 

comments regarding the petition process for the categorical 

listings, as well as our rationale for the categorical 

rulemaking petition process, can be found in section III.D.4 of 

this preamble.

5. Streamlining of the 40 CFR 241.3(c) Non-Waste Determination 

Petition Process
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In today’s final rule, the agency is streamlining the nonwaste determination provisions under 40 CFR 241.3(c). The public 

participation process was streamlined to accommodate petitions 

that apply to multiple combustors. In particular, the 

regulations were adjusted to indicate that the appropriate 

office in the EPA headquarters may handle petitions that cross 

multiple regions. Furthermore, if a determination is made that 

the NHSM is a non-waste, the decision will be retroactive and 

apply on the date the petition was submitted. A discussion of 

relevant comments regarding the streamlining of the 40 CFR 

241.3(c) non-waste determination petition process, as well as 

our rationale for the streamlining changes made to the non-waste 

determination process, can be found in section III.D.6 of this 

preamble. 

6. Revised Introductory Text for 40 CFR 241.3(a)

In today’s final rule, the agency has decided not to revise 

the introductory text of 40 CFR 241.3(a). In its December 2011 

proposed rule, the EPA considered revising this introductory 

text to state that NHSMs are “presumed to be” solid wastes, 

rather than “are” solid wastes. While the proposed change was 

not expected to be a substantive change to the rule, but merely 

a reflection of the record at the time, it did engender some 

confusion among commenters. Based on the comments received, we 

have decided not to issue revised introductory text 40 CFR 
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241.3(a) and, thus, this section will continue to read as 

codified in the March 2011 NHSM final rule. A discussion of 

relevant comments regarding the introductory text of 40 CFR 

241.3(a), as well as our rationale for this decision, can be 

found in section III.D.7 of this preamble. 

D. Comments on the Proposed Rule and Rationale for Final 

Decisions

In this section, the EPA addresses major comments the 

agency received regarding the targeted revisions that were 

proposed to certain part 241 provisions in the December 23, 

2011, proposal. In discussing the comments received on the 

proposal, we also provide the rationale for making the revisions 

that are finalized in today’s action. As previously discussed, 

the agency specifically stated that it would not address 

comments that go beyond the scope of this narrow RCRA 

rulemaking. 

1. Revised Definitions

a. Clean Cellulosic Biomass

The proposed rule suggested revising the March 2011 

definition of “clean cellulosic biomass” to list additional 

examples of biomass materials that are appropriately included 

within this definition. These fuels are not secondary materials 

or solid wastes unless discarded. Clean biomass is “biomass that 

does not contain contaminants at concentrations not normally 
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associated with virgin biomass materials” (codified in 40 CFR 

241.2).

This regulatory revision would not change the agency’s 

intent under the March 2011 final rule, but would identify 

additional materials that are “clean cellulosic biomass,” and, 

thus, would be a traditional fuel under these regulations. While 

the list of clean biomass materials is only illustrative and not 

exhaustive, it is now more comprehensive than the list that 

appeared in the definition included in the 2011 NHSM final rule.

One of the materials within the definition is clean C&D 

wood. In light of some confusion in comments regarding C&D wood, 

the EPA is clarifying the meaning of the term in the definition 

of “clean cellulosic biomass.” Construction & demolition wood 

actually may be placed into different categories, depending upon 

its origin. In accordance with the traditional fuels definition 

in section 241.2, clean C&D wood could be combusted as a 

traditional fuel if it does not contain contaminants at 

concentrations not normally associated with virgin wood. 

However, the final NHSM rule also addressed C&D wood that 

may contain contaminated material.17 There is no need to repeat 

these discussions here, except to clarify what the final rule 

means. In general, contaminated C&D wood that has been processed 

(e.g., sorted) to remove contaminants, such as lead-painted 

 

17 See 76 FR 15485.
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wood, treated wood containing contaminants, such as arsenic and 

chromium, metals and other non-wood materials, prior to burning, 

likely meets the processing and legitimacy criteria for 

contaminants, and thus can be combusted as a non-waste fuel (see 

further discussion in response to comments below). 

Comment: One commenter noted that the EPA's specific 

inclusion of "untreated wood pallets" implicitly accepts that 

small amounts of non-wood material inherent to the pallets, such 

as screws or plastic fasteners, do not render those materials 

solid waste under the rule, and de minimis amounts of nonbiomass material would not require these types of materials to 

be burned in incinerators under the CISWI rule. 

Another commenter requested that the EPA reconsider use of 

the word “untreated” when referring to wood pallets. The 

commenter argues that the EPA does not define the word 

“untreated” and its use could create confusion. Rather, the 

commenter recommends that “untreated” be replaced with the word 

“clean,” which is an adjective used in the definition to 

distinguish other materials (e.g., “clean construction and 

demolition wood”).

Response: Wood pallets are refurbished or recycled for 

other uses by pallet recyclers. When the useful life of the 

pallet is finished, the recyclers typically remove the small 

amount of non-wood material inherent to pallets that would 
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inhibit combustion, such as screws or plastic fasteners. The 

pallets are then ready for use as fuel, and the non-wood 

material would not impact whether the material can be burned in 

combustion units that meet the CAA section 112 emission 

standards. The agency is not aware of instances where the 

pallets are used as fuel directly by the original users and nonwood material is left remaining in the pallet. Such pallets 

would not be considered clean cellulosic biomass under the rule. 

With respect to the other comment, the EPA does not agree, 

that the term “untreated” wood pallet be replaced with the term 

“clean” wood pallet. The term “clean” is defined in the 

traditional fuels definition as described above, and applies to 

all the materials listed in the definition of clean cellulosic 

biomass, which includes untreated wood pallets. It would be 

redundant to define “clean” biomass as including “clean” wood 

pallets. The point is that some wood pallets may contain treated 

wood, such as CCA treated wood, and inclusion of the term 

“untreated” with wood pallet would help emphasize that such 

treated wood would not be considered “clean” under the 

definition of clean cellulosic biomass. 

Comment: Several commenters indicated that the definition 

of clean cellulosic biomass remains ambiguous because it 

continues to include the caveat that: “Clean biomass is 

biomass that does not contain contaminants at concentrations not 
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normally associated with virgin biomass materials.” Thus, 

notwithstanding the EPA’s attempt at expanding the definition of 

clean cellulosic biomass, the commenters believed that this 

sentence should be removed because it perpetuates uncertainty. 

It is not clear what comparisons are permissible and what 

concentration levels are appropriate. 

The commenters also indicated that this sentence 

perpetuates the EPA’s erroneous interpretation of its authority 

under RCRA. A material does not become a waste when burned for 

energy recovery just because it may contain contaminants --

prior to combustion -- not normally associated with virgin 

biomass. It becomes a waste only if it is combusted for the 

purpose of disposal, rather than for energy recovery. 

Response: The agency disagrees with the commenter that 

defining the term “clean” leads to ambiguity in identifying 

which materials are clean cellulosic biomass. On the contrary, 

defining the term “clean” is meant to ensure that contaminated 

cellulosic material being burned, such as lead-painted wood or 

arsenic treated wood, does not introduce contaminants (as 

defined in 40 CFR 241.2) not normally associated with virgin 

biomass materials. 

The agency wishes to emphasize, however, that 

determinations that the cellulosic biomass used as a fuel or 

ingredient is clean, do not presuppose any testing of 
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contaminant levels. Persons can use expert or process knowledge 

of the material to justify decisions regarding presence of 

contaminants. 

With respect to the comment that burning of contaminated 

material does not make it a waste, the agency has not reopened 

this issue for this rule and stands by its responses in the 

rulemaking record for the March 2011 final rule.18

Comment: One commenter provided the example of whether 

treated seeds that contain additives are considered contaminants 

in virgin biomass. These additives may not be found in virgin 

seeds but are not harmful at the concentrations found in the 

seeds. The commenter questioned whether any concentration above 

“natural” (concentration levels found in virgin material), 

especially when combusted as fuel, would be prohibited and 

require additional waste regulation.

Response: Seeds may be treated with pesticides and hormones 

to aid in germination. Such chemicals do not generally include 

 

18 See, for example, 76 FR 15523-4: “If a non-hazardous secondary material 

contains contaminants that are not comparable to those found in traditional 

fuels, and those contaminants are related to pollutants that are of concern 

at solid waste combustion units, then it follows that discard is occurring. 

The contaminants in these cases could not be considered a normal part of a 

legitimate fuel and are being discarded, either through destruction in the 

combustion unit or through releases into the air. Units that burn such 

materials are therefore most appropriately regulated under the CAA section 

129 standards for solid waste incinerators.” See also 76 FR 15485, which 

states: “[A]s we have noted previously, the criterion or test for determining 

whether a material is burned as a waste or a commodity fuel is the level of 

the contaminant in the secondary material itself – that is destruction of 

contaminants indicates a waste treatment activity rather than a commodity 

fuel.”
Page 124 of 319

contaminants as defined in section 241.2; therefore, such 

treated seeds would generally be considered clean cellulosic 

biomass. 

Comment: Several commenters indicated that, as part of the 

EPA’s changes in the definition of clean cellulosic biomass, it 

is proposing to consider treated or painted wood the same as 

“virgin” wood if it has lower than de minimis levels of 

contamination. While adoption of numerical values in the rule 

would require additional provisions for measurements and would 

require additional notice, the commenter believes that such 

clarity is important for successful implementation of the rule. 

Such limits would be applied to “clean” C&D material, for 

instance, among other potential fuel types. The term de minimis 

is not defined numerically in the proposed rule and the 

commenters argue that without a specific numerical de minimis 

limit, sources would not have a clear understanding of whether 

they fall under the CISWI or hazardous waste incinerator rules. 

The commenter recommended that the EPA define and allow for 

public comment on the levels associated with the term de minimis 

and base the de minimis levels on contaminant levels found in 

typical “virgin” wood. 

Response: Regarding the addition of a definition for de 

minimis amounts of contaminants remaining in processed wood, the 

agency does not believe it appropriate to identify specific 
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concentration levels. Rather, the agency interprets de minimis 

as that term is commonly understood -- insignificant or 

negligible amounts of contamination (e.g., small wood sliver 

containing lead paint). 

As indicated above, there also appears to be confusion 

among commenters regarding two different categories of C&D wood

- - “clean C&D wood” that is a traditional fuel, and C&D wood 

that has been processed to remove contaminants. Under the 2011 

NHSM final rule, C&D wood that has been processed (e.g., sorted) 

to remove contaminants, such as lead-painted wood, treated wood 

containing contaminants, such as arsenic and chromium, metals 

and other non-wood materials, prior to burning, likely meets the 

processing and legitimacy criteria for contaminants, and thus 

can be combusted as a non-waste fuel but would not be considered 

“clean C&D wood.” Such C&D wood may contain de minimis amounts 

of contaminants and other materials provided it meets the 

legitimacy criteria for contaminant levels. To meet the 

contaminant legitimacy criterion, concentration levels of 

contaminants in the processed C&D wood must be comparable to or 

less than the levels in the traditional fuel the unit was 

designed to burn, whether wood or another traditional fuel (see 

section III.D.2 for a discussion on contaminant comparisons). In 

contrast, “clean C&D wood” is a traditional fuel that does not 

require processing and meets the definition of “clean” (i.e., 
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C&D wood that does not contain contaminants at concentrations 

not normally associated with virgin biomass (wood)). Thus, de 

minimis amounts of contaminants and other material appropriate 

for processed C&D wood would not be appropriate for clean wood 

that is a traditional fuel.

Comment: One commenter argued that states should have 

discretion about how to determine appropriate fuel quality but 

it should be no less stringent than limits set by the EPA. There 

should be a distinction between de minimis levels of 

contamination in C&D wood and a fuel quality standard. 

Response: We do not necessarily disagree with the 

commenter. That is, as discussed in the final rule, part 241 

does not preempt a state’s statutory or regulatory standards and 

states are free to establish fuel quality standards for C&D 

wood. However, we would also note that as solid waste is defined 

by the EPA under RCRA, such state standards would not 

necessarily impact the status of the material as it relates to 

which combustion units are subject to CAA section 129 (56 FR 

15546). 

b. Contaminants

The December 2011 rule proposed to clarify what 

constituents will be considered contaminants by making the 

definition of “contaminants” more specific. However, the 
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proposal maintained the fundamental approach—and was intended to 

cover the same constituents—as the March 2011 final rule.

The March 2011 final rule and the December 2011 proposed 

rule identified the same three ways a chemical can be labeled a 

contaminant. First, it may be one of the 187 HAP currently 

listed in CAA section 112(b); second, it may be one of the nine 

pollutants listed under CAA section 129(a)(4); and third, it may 

be one of a handful of chemicals whose combustion will result in 

the formation of listed CAA section 112(b) and section 129(a)(4) 

pollutants (e.g., sulfur that will result in SO2). 

The definition proposed in December provided clarification 

by listing the constituents that belong to the third group.19

Specifically, the proposed revision replaced a potentially 

ambiguous reference to “any constituent that will result in 

emissions” with the four specific elements the agency intended 

to be considered as contaminants (chlorine, fluorine, nitrogen, 

and sulfur) based on their status as a precursor to air 

emissions. In all four cases, the CAA pollutant itself (e.g., 

SO2) is not likely to be present in the NHSM prior to 

combustion, and the only way to measure constituents prior to 

combustion “that will result in emissions” of that pollutant is 

to measure a known precursor (e.g., sulfur) instead. For each of 

 

19 Eleven metal elements directly identified in CAA section 112(b) were also 

listed in the proposed definition to provide the regulated community with a 

complete list of elements that are considered “contaminants” under the rule.
Page 128 of 319

the four precursor elements listed as contaminants in the 

proposal, the expected fate for the precursor during combustion 

is formation of the aforementioned pollutant and the precursor 

makes no substantive contribution to the material’s value as a 

fuel. For these reasons, the agency proposed to specifically 

identify chlorine, fluorine, nitrogen, and sulfur as 

contaminants in place of HCl, HF, NOx and SO2. By limiting the 

list of precursors considered contaminants to these four 

elements, the revised definition also made clear that the agency 

did not intend to include other elements present in contaminants 

(such as hydrogen and carbon) as contaminants themselves.

The December 2011 proposed rule also removed from the 

definition of contaminants those pollutants in CAA sections 

112(b) and 129(a)(4) that we do not expect to find in any NHSM. 

Specifically:

Chlorine gas, HCl, HF, NOx, and SO2 were removed from the 

definition because they are unlikely to be found in NHSMs 

prior to combustion and had been replaced by the elements 

chlorine, fluorine, nitrogen and sulfur as discussed above;

Fine mineral fibers were removed because they are releases 

from the manufacturing and processing (not combustion) of 

non-combustible rock, glass or slag into mineral fibers;

Particulate matter and coke oven emissions were removed 

because they are products of combustion unlikely to exist 

in NHSMs prior to combustion;

Cresol isomers m-cresol, o-cresol, and p-cresol were 

removed because the listed pollutant cresols/cresylic acid 

includes these three isomers;
Page 129 of 319

Xylene isomers m-xylene, o-xylene, and p-xylene were 

removed because the listed pollutant xylenes includes these 

three isomers; and

Diazomethane, white phosphorus, and titanium tetrachloride 

were removed because their high reactivity makes their 

presence in NHSMs very unlikely.

In addition, two phrases present in the March 2011 final 

rule “contaminants” definition were not included in the December 

2011 proposed rule definition. First, the phrase concerning 

constituents “that will result in emissions of the air 

pollutants” was removed since the regulated community had 

expressed confusion that in determining whether or not a NHSM 

meets the contaminant legitimacy criterion, emissions from the 

combustion unit were to be evaluated. The EPA disagreed and 

directed readers to the language in sections 241.3(d)(1)(iii) 

and 241.3(d)(2)(iv). These sections state that contaminant 

comparisons are based on the presence of contaminants in the 

NHSM (or products made from NHSMs in the case of ingredients), 

not the resulting emissions. The proposed revision also inserted 

the phrase “prior to combustion” into the contaminants 

definition to further emphasize that the NHSMs, not the 

emissions that result from NHSMs, are to be evaluated when 

conducting contaminant comparisons. The rationale for evaluating 

the NHSM, and not emissions, can be found in the record for the 
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March 2011 final rule.20 The proposal merely added language to 

ensure the rule is consistent with the agency’s intent.

The second phrase proposed to be removed from the March 

2011 final rule definition was a reference to “those 

constituents that could generate products of incomplete 

combustion,” also referred to as PICs. This reference was 

removed from the definition because it was duplicative and 

potentially misleading. Specifically, this phrase was not 

necessary because all PICs that the agency considers air 

pollutants—including dioxins, dibenzofurans, PCBs and PAHs—are 

listed in CAA sections 112(b) or 129(a)(4) and are thus already 

included in the “contaminants” definition. More importantly, the 

phrase was potentially misleading because PIC formation depends 

heavily on combustion conditions, such as air/fuel ratio and 

mixing. These conditions are controlled to limit emissions and 

neither these conditions nor emissions are the subject of this 

rule. The NSHM itself is the subject of this rule. Thus, the 

removal of both phrases clarified—but did not alter—the 

constituents subject to the contaminant legitimacy criterion.

The EPA believes that comments have not changed the basis 

for listing specific precursors to air emissions as 

contaminants, nor have they changed the basis for either 

excluding specific constituents from the definition or removing 

 

20 For example, see 76 FR 15524-15525.
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the references to “that will result in emissions of the air 

pollutants” and “constituents that could generate products of 

incomplete combustion” from the definition. Thus, the EPA is 

adopting the reasoning from the proposal and revising the 

definition of contaminants to incorporate these concepts. 

The EPA has decided, however, to make several modifications 

to the regulatory language of the December 2011 proposed rule 

based on comments received and information in the rulemaking 

record. First, in the final definition issued today, precursors 

will only be considered contaminants for NHSMs used as fuels; 

precursors will not be considered contaminants for NHSMs used as 

ingredients. Furthermore, precursors will not be considered 

contaminants if they do not form their corresponding pollutants. 

Also, opacity has been removed from the contaminants definition. 

Finally, the phrase “prior to combustion” has not been inserted 

into the contaminants definition, as had been proposed. 

Contaminants in NHSMs used as fuel in combustion units must 

still be evaluated prior to combustion, and persons must still 

evaluate the NHSM itself (not emissions), but the agency has 

determined that the topic of when to evaluate contaminants is 

more appropriate to address in the legitimacy criteria than in 

the contaminants definition. 
Page 132 of 319

Additional reasoning for keeping the rule provisions as 

proposed, and for any modifications to the proposed language, 

are described in the following responses to comments.

Comment: Several commenters stated that the definition of 

contaminants should focus on contaminants released as combusted 

emissions. One commenter argued that contaminants should be 

compared between emitted contaminants and emission standards. A 

second commenter reiterated previous comments that contaminant 

levels should be related to the air emissions and not the 

content of the material. For support, commenters cited that the 

EPA reversed its position in the proposal by using possible air

emissions as the basis for establishing what contaminants need 

to be compared.

Response: The EPA has previously stated that contaminant 

levels before and after combustion can be important indicators 

of legitimacy and it maintains the position from the March 2011 

final rule that non-waste fuels must be similar in composition 

to traditional fuels prior to combustion.21 Because combustion 

and emission control processes can destroy or remove 

contaminants, a comparison of emissions profiles alone only 

tells one how well the combustion unit is operating, not whether 

 

21 See 76 FR 15525.
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the NHSM is being used as a legitimate non-waste commodity 

fuel.22 

The EPA disagrees with the comment that the agency reversed 

its position on the consideration of emissions in the proposal 

by including precursors to air emissions as contaminants. The 

agency notes that a difference exists between comparing 

“emissions” and comparing “contaminants that will result in 

emissions,” the exact language used in the March 2011 final 

rule. The EPA has clarified what it intended by “contaminants 

that will result in emissions” in today’s final action. This 

clarification involves the listing of specific precursors known 

to result in emissions of air pollutants when combusted; it also 

involves the removal of specific pollutants known not to be 

present in NHSMs. 

Comment: Two commenters expressed concern that the proposed 

definition of contaminants conflicted with the contaminant 

legitimacy criterion for NHSMs used as ingredients in combustion 

units. Commenters stated that both the definition of 

contaminants, as proposed, and the existing contaminant 

legitimacy criterion for ingredients were clear when read 

separately but were contradictory when taken together. The 

commenters encouraged the EPA to clarify the regulatory text. 

Specifically, the commenters noted that for ingredients, 

 

22 Id. 
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contaminants could not be evaluated prior to combustion and then 

used to compare products produced using NHSMs to products 

produced using traditional materials. 

Response: The EPA has decided not to include language from 

the December 2011 proposed rule in the definition of 

contaminants that emphasized when NHSM contaminant levels are to 

be evaluated (i.e., before or after combustion). While the 

proposed additional language made clear that NHSMs used as a 

fuel were to be evaluated for contaminants “prior to 

combustion,” the agency agrees with the two commenters who 

argued that the proposed language conflicts with the contaminant 

legitimacy criterion for ingredients. The contaminant criterion 

for ingredients requires comparisons to be made between products 

produced with and without NHSMs, but until the products exist,

they cannot be compared. 

As such, the agency has decided not to adopt the proposed 

additional language addressing when contaminants are to be 

evaluated in the definition of contaminants. The agency proposed 

similar language in the December 2011 rule addressing this topic 

in the contaminant legitimacy criterion and the agency is 

adopting that language in today’s final rule. The agency has 

determined that the legitimacy criteria themselves (40 CFR 

241.3(d)(1)(iii) for fuels and 40 CFR 241.3(d)(2)(iv) for 

ingredients) are more appropriate places to address this topic.
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The EPA has also decided to add language to the definition 

of contaminants clarifying that the specification of particular 

precursors to air emissions (i.e., chlorine, fluorine, nitrogen 

and sulfur) as contaminants does not apply to the contaminant 

legitimacy criterion for ingredients. As identified by the 

commenters, the contaminant criterion for ingredients requires 

comparisons to be made between products produced with and 

without NHSMs. Products can only be compared after combustion 

has occurred, at which point there will be no benefit to 

measuring levels of precursors. 

The agency also notes that it does not envision a situation 

where NHSMs containing chlorine, fluorine, nitrogen or sulfur 

would be used as ingredients in such a way that would emit 

higher levels of HCl, HF, NOx or SO2 than would be emitted using 

traditional ingredients without the material being considered a 

solid waste. In all cases, ingredients must provide a valuable 

contribution to the product being produced, and that product 

must itself be valuable, in order to not be considered a solid 

waste. For an ingredient to provide value, the agency expects 

the ingredient to remain in a product rather than be destroyed 

or released via emissions. This is a key reason why the 

contaminant legitimacy criterion for ingredients focuses on 

products (i.e., toxics along for the ride) rather than 

emissions. Furthermore, the legitimacy criteria for ingredients 
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cannot be used to avoid the legitimacy criteria for fuels if the 

material is being used for both purposes. 

Comment: Several commenters questioned the rationale for 

including precursors to air emissions as “contaminants” under 

the proposed revised definition. Some indicated that the concept 

is far removed from the true meaning of “discard,” with one 

comment stating that the EPA has no legal, rational or 

scientific basis for considering the presence of sulfur or 

nitrogen in NHSMs as evidence of intent to discard SO2 or NOx

during combustion. To support this argument, the commenter first 

noted that the EPA has no record basis for assuming that the 

intent of the combustor is to discard the constituent, rather 

than to generate energy. Second, the commenter noted that 

whether or not a boiler has emissions of regulated air 

pollutants, such as SO2 or NOx when it combusts a precursor will 

depend, not on an intent to discard these pollutants, but on 

boiler operation and design. 

Two commenters also stated that the preamble discussion on 

precursors demonstrates how far removed the EPA’s rational for 

this rulemaking is from the concept of discard. They noted that 

the EPA is requiring combustors to document and keep records 

regarding the fact that CO is not present in NHSMs, and, under 

CISWI, would identify the NHSM as waste if this documentation is 
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not maintained. The commenters failed to see how this has 

anything to do with a determination that a material is a waste 

under RCRA. 

Response: The EPA disagrees with these comments. Precursors 

to emissions of identified air pollutants are important and 

appropriate to address as contaminants in NHSMs prior to 

combustion. It is also necessary to tailor the definition of 

contaminants to the realities of the combustion process, during 

which precursors present in NHSMs used a fuel—many of which are 

solid or liquid—are transformed into air pollutants. 

However, the agency agrees with those commenters who argued 

that the revised definition, as proposed, may be too broad with 

regard to precursors that may not form air pollutants in all 

cases. For example, if the combustion of nitrogen does not form 

NOx in a particular situation, the agency did not intend in its 

December 2011 proposed rule to consider nitrogen as a 

contaminant in that particular situation.

23 The EPA noted in the 

proposed rule that chlorine, fluorine, nitrogen and sulfur will 

form pollutants of concern in most circumstances, but the agency 

does acknowledge that specific technologies and practices may 

prevent these transformations from happening in the first 

 

23 See March 16, 2012 Response from James R. Berlow, Director, Program 

Implementation and Information Division, EPA’s Office of Resource 

Conservation and Recovery to Fadi K. Mourad, DTE Energy Services, Inc. A copy 

of this response letter has been placed in the docket for today’s rulemaking 

and is also available at http://www.epa.gov/epawaste/nonhaz/define/index.htm.
Page 138 of 319

instance, particularly with regard to nitrogen (one example 

being the use of Low NOx burners with Over-Fire Air). Thus, the 

contaminants definition issued in today’s final rule does not 

consider constituents that are normally precursors to CAA 

section 112(b) or 129(a)(4) pollutants to be contaminants if a 

specific technology or practice prevents them from forming their 

corresponding pollutants.

The definition codified in 40 CFR 241.2 only includes 

chlorine, fluorine, nitrogen and sulfur as contaminants in cases 

where “combustion will result in the formation of hydrogen 

chloride (HCl), hydrogen fluoride (HF), nitrogen oxides (NOx), 

or sulfur dioxide (SO2).” When compared to the December 2011 

proposed rule, the only constituents no longer considered 

contaminants due to this modification are chlorine that will not 

form HCl during combustion, fluorine that will not form HF 

during combustion, nitrogen that will not form NOx during 

combustion and sulfur that will not form SO2during combustion. 

This is consistent with the March 2011 NHSM final rule, under 

which these constituents would not be contaminants when they 

would not “result in emissions” of CAA section 112(b) or section 

129(a)(4) pollutants.

Although the EPA is not currently aware of any technologies 

or practices that prevent chlorine, fluorine or sulfur in NHSMs 
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from forming their associated pollutants during combustion (the 

EPA is aware of such examples with nitrogen), the agency 

considers it reasonable and appropriate to adopt the same 

language for all four precursors to allow for future 

technological advances preventing the transformation of these 

elements into pollutants during combustion. 

Comment: One commenter stated that the consideration of 

precursors to air emissions as contaminants could be used to 

make the most fundamental of all elements, hydrogen, a 

contaminant because it is present in nearly all regulated 

pollutants. The presence of hydrogen in a NHSM could then be 

considered evidence of intent to discard pollutants that 

contained hydrogen.

Response: Under the proposed contaminants definition, only 

the specific precursor elements listed (chlorine, fluorine, 

nitrogen and sulfur) are considered contaminants. The EPA 

determined in the proposal, and adopts as its final decision 

today, that these are the only four precursors necessary to 

evaluate when comparing contaminants between NHSMs and 

traditional fuels. The agency specifically decided not to 

include hydrogen on this list. Whereas combustion of chlorine, 

fluorine, nitrogen and sulfur typically leads to the formation 

of CAA section 112(b) or 129(a)(4) air pollutants, combustion of 

hydrogen typically leads to the formation of water vapor.
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Comment: Several commenters opposed the inclusion of 

precursors as contaminants on the ground that the formation of 

related pollutants depends more on boiler operation and design, 

process chemistry and feedstock characteristics than on the 

levels of precursors present in the NHSMs.

Response: The EPA recognizes that unit design and operating 

conditions can impact the transformation of chlorine, fluorine, 

nitrogen and sulfur into air pollutants. Rather than viewing 

this as a reason to ignore the pollutants these elements 

commonly form, the agency views this as further evidence why 

precursor levels must be considered when determining which set 

of CAA standards—which in turn regulate unit operating 

conditions—should apply.

Comment: Two commenters suggested that the EPA follow a 

different approach for defining contaminants and use a method 

similar to what the agency used for the used oil specification 

in 40 CFR 279.11. In each case, the commenter suggested that for 

NHSMs, the definition of contaminants should be limited to 

sulfur, nitrogen, chlorine, Cd, Hg and lead because those are 

the elements Congress addressed in CAA section 129. This 

approach, they argued, would be similar to what the EPA did when 

developing the used oil specifications. The point the commenters 

wished the agency to draw from the used oil specification 

approach is that it addressed elemental species, as opposed to 
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individual compounds. Using sulfur as an example, the commenters 

reasoned that it is the underlying presence of sulfur-bearing 

materials in the NHSMs, as opposed to individual sulfurcontaining compounds on the section 112(b) list, which effects 

emissions of SO2. 

Response: The EPA disagrees with the approach outlined by 

the commenters and has issued a final definition of contaminants 

based on both the CAA section 112(b) and the CAA section 

129(a)(4) lists, as was proposed. We do agree with the 

commenters, however, that identifying precursors that will form 

certain CAA pollutants in the definition of contaminants is 

appropriate. The approach outlined by the commenters appears to 

be based on two premises that the EPA has previously considered 

and decided not to adopt. 

First, the commenters do not think the definition of 

contaminants should reference both the CAA section 112(b) and 

CAA section 129(a)(4) lists. The agency previously explained its 

decision to use both lists in the March 2011 final rule and does 

not believe comments have offered any new information that would 

change the basis for this decision. The EPA previously discussed 

that both lists of constituents are appropriate because both 

lists are to be considered by the EPA when developing emission 
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standards.24 Furthermore, the agency has previously explained 

that CAA section 129 provides that the term “solid waste” shall 

have the meaning promulgated by the EPA under RCRA and that the 

EPA has the authority to interpret RCRA to decide whether NHSMs 

are solids wastes or not.25 The agency notes that it has 

carefully considered the CAA section 112(b) and 129(a)(4) lists 

of pollutants and removed those constituents that would not be 

appropriate to evaluate in NHSMs.

Second, the commenters base their proposed approach to 

defining contaminants purely on emissions. The agency agrees 

that emissions may be a means of discard but contaminants that 

are destroyed by the combustion process or incorporated into 

products may not have emission standards established under CAA 

section 129. Combustion may still be a means of discard in these 

instances. Thus, a definition of contaminants based only on the 

CAA section 129 emissions standards only tells one how well the 

combustion unit is operating, not whether the NHSM is being used 

as a legitimate non-waste commodity.26

Comment: Several commenters addressed the specific 

constituents proposed to be removed from the definition of 

contaminants. In general, comments were supportive of the 

concept that constituents unlikely to be found in NHSMs prior to 

 

24 See 76 FR 15524-15525. See also, 75 FR 31883. 

25 See 76 FR 15469-15470. See also, 76 FR 15473.

26 See 76 FR 15525.
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combustion or adequately measured elsewhere in the definition 

should be removed from the definition. 

Multiple commenters asked that CO also be removed from the 

definition because it is unlikely to be found in NHSMs. The same 

commenters asked that opacity be removed from the definition 

because it can only be measured in emissions and is not directly 

related to any one specific constituent in NHSMs. Particulate 

matter and coke oven emissions were removed, noted the 

commenters, because they are products of combustion unlikely to 

exist in NHSMs prior to combustion, and the same can be said for 

CO and opacity. 

One commenter expressed concern that asbestos had been 

removed from the list due to the removal of “fine mineral 

fibers” as a contaminant. The commenter explained that asbestos 

is commonly found in construction and demolition debris and 

asbestos particles in smoke are deadly. Excluding fine mineral 

fibers from regulation explicitly ignores the possibility of 

such contamination in C&D debris, noted the commenter, and 

asbestos should be a regulated contaminant.

Response: The EPA has issued a final rule containing the 

language removing constituents from the definition of 

contaminants as proposed, with one change. The agency has 

removed “opacity” from the final definition of contaminants as 

well. Similar to PM and coke oven emissions, there is no 
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practical way to measure opacity in NHSMs prior to combustion or 

in products made using NHSMs. In fact, the EPA did not intend 

for opacity to be included in the definition of contaminant 

under the previous definition. A visual property of an emissions 

stream, opacity is not even a constituent, let alone a 

constituent that can be measured in NHSMs prior to combustion or

in products made using NHSMs. As such, removing it from the 

definition will provide clarity without effecting any practical 

change to the definition.27

The agency has not removed CO from the definition of 

contaminants because, contrary to comments that it is unlikely 

to be found in any NHSM, it is likely to be present in gaseous 

NHSMs and is not adequately measured elsewhere in the 

“contaminants” definition. However, as we discuss in the 

December 2011 proposed rule, CO is unlikely to be found in solid 

or liquid NHSMs and EPA expects that persons can use process 

knowledge to justify not testing for CO in these cases.28

The agency has removed the fine mineral fibers group from 

the definition of contaminants, as proposed, because they are 

not expected to be found in NHSMs. Fine mineral fibers, as 

regulated under CAA section 112(b) are releases from the 

manufacturing and processing of non-combustible rock, glass or 

 

27 Neither Table 7 nor Table 8 in the December 2011 proposed rule included 

opacity. See 76 FR 80478-80480.

28 See 76 FR 80475
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slag into mineral fibers and are not produced during the 

combustion process. Asbestos, on the other hand, has been set 

apart from the fine mineral fibers group in CAA section 112(b), 

and thus, it is set apart in the NHSM rule. To be clear, 

asbestos is included in the definition of contaminants in 

today’s final rule and it would be a contaminant regardless of 

whether the fine mineral fibers group was removed or not. 

In summary, the following 12 CAA section 112(b) and section 

129(a)(4) pollutants have been removed from the definition of 

contaminants: HCl, Cl2, HF, NOx, SO2, fine mineral fibers, PM, 

coke oven emissions, opacity, diazomethane, white phosphorus and 

titanium tetrachloride. 

c. Established Tire Collection Programs

The 40 CFR part 241.2 definition for “established tire 

collection program,” as established by the March 2011 

promulgation in the Federal Register, was as follows: 

“Established tire collection program means a comprehensive 

collection system that ensures scrap tires are not discarded and 

are handled as valuable commodities in accordance with section 

241.3(b)(2)(i) from the point of removal from the vehicle 

through arrival at the combustion facility.”

In the December 2011, NHSM proposed rule, the EPA proposed 

to revise this definition (and the related criteria for nonwaste tires now at 40 CFR 241.4(a)(1)) in order to account for 
Page 146 of 319

off-specification tires. The term “off-specification tires” is 

intended to also include “factory scraps.” The off-specification 

tires are not removed from vehicles and are handled under 

contractual arrangements which ensure they are not discarded. 

The definition was modified to include “contractual arrangement” 

to provide that not only “collection systems,” but also 

contractual arrangements for tire collection would be 

appropriate. The requirement for the tires to be removed from 

the vehicle was eliminated29 since it is not applicable to offspecification tires. The revised definition is sufficient to 

encompass the agency’s intent in describing these programs and 

continues to ensure that these scrap tires are not discarded and 

are handled as valuable commodities through arrival at the 

combustion facility. Further, the addition to the new 

categorical non-waste provision at 40 CFR 241.4(a)(1) eliminated 

the need for the previous scrap tire provision at 40 CFR 

241.3(b)(2)(i),30 (which has been removed and reserved in today’s 

final rule) therefore, the reference to that provision was 

 

29 The related tire provision at 241.4(a)(1) allows for tires that are offspecification or are removed from vehicles. 

30 The scrap tire provision in the 2011 NHSM final rule is now removed and the 

section reserved in today’s final rule: “(b) The following non-hazardous 

secondary materials are not solid wastes when combusted:

(2) The following non-hazardous secondary materials that have not been 

discarded and meet the legitimacy criteria specified in paragraph (d)(1) of 

this section when used in a combustion unit (by the generator or outside the 

control of the generator):

(i) Scrap tires used in a combustion unit that are removed from vehicles and 

managed under the oversight of established tire collection programs.”
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removed in the definition. The agency proposed to revise the 

definition as follows: “Established tire collection program 

means a comprehensive collection system or contractual 

arrangement that ensures scrap tires are not discarded and are 

handled as valuable commodities through arrival at the 

combustion facility.”

The definition in today’s final rule includes the revisions 

to the definition we proposed in December 2011. In addition, the 

agency is including in the definition “tires that were not 

abandoned and were received from the general public at 

collection program events.” This revision is being made based on 

comments received on the proposed rule as discussed below. Under 

today’s revised definition, established tire collection programs 

could also include a “contractual arrangement.” If, for example, 

the state is sponsoring special events where they take tires 

back from the general public, those tires would also be 

included. Thus, the definition in today’s final rule is 

“Established tire collection program means a comprehensive 

collection system or contractual arrangement that ensures scrap 

tires are not discarded and are handled as valuable commodities 

through arrival at the combustion facility. This can include 

tires that were not abandoned and were received from the general 

public at collection program events.” 
Page 148 of 319

While the agency did receive comments on the specific 

proposed changes described above, a number of commenters 

rephrased or restated previous arguments which conclude that any 

tires burned for energy recovery are not wastes, even if 

previously discarded. Conversely, one commenter reiterated its 

previous arguments which conclude that all used tires are waste, 

even if burned for energy recovery. Today’s rule is responding 

only to the specific proposed revisions to the regulations and 

the requests for comment in the proposal. For the response to 

other issues, refer to the record for the 2011 NHSM final rule 

(76 FR 15456). Many of the commenters who provided comments on 

tires intertwined the “established tire collection program” 

definition issues with the related topic of the categorical nonwaste provision for scrap tires. For a discussion of those 

comments, refer to the response to comments for the categorical 

non-waste provision for scrap tires (section III.D.3.a.). The 

EPA is not reopening its decision that these scrap tires are not 

wastes. That decision, however, justifies a categorical 

exclusion where there is not a need to make case-by-case 

determinations regarding discard in the first instance and the 

legitimacy criteria. 

Comment: Several commenters mentioned that, in some cases, 

the public individually takes tires to state-run tire collection 

program events. These are tires that the general public owns and 
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were typically removed from their vehicle. These are not 

abandoned tires. These collection events, in some cases, are 

held by the combustor under the state’s environmental program 

oversight. In those cases, the combustors enter into agreements 

with local communities to hold these events during which local 

residents are allowed to bring tires to facilities to be 

recycled, including used as alternative fuels. The scope of tire 

collection programs also may allow the public to take used tires 

which they may have stored in their garages, or elsewhere on 

their property, directly to a combustion facility – in many 

cases a cement kiln. 

Under the EPA’s current definition of tire collection 

programs, the commenters said it is not clear whether these 

tires would qualify as those collected under an “established 

tire collection program.” Commenters generally agreed that these 

tires are not abandoned and should be utilized as non-waste 

fuels without processing. 

Response: The EPA agrees with the commenters that tires 

that have not been discarded and are collected directly from the 

public at tire collection events are intended to qualify for the 

40 CFR 241.4(a)(1) requirement to be “managed under the 

oversight of established tire collection programs.” The agency 

agrees that these tires are not abandoned and when collected 

under established tire collection program events, they are 
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considered to be non-waste fuels, just as the other tires 

handled by established tire collection programs are non-waste. 

To make this point clear, the EPA has modified the regulatory 

language. Please refer to the Response to Comment document for 

more details on these collection events and the responses. 

2. Contaminant Legitimacy Criterion for NHSMs Used as Fuels

Under the December 2011 proposed rule, revisions to the 

contaminant legitimacy criterion for NHSMs used as fuel provided 

details on how contaminant comparisons could be made in 

practice. The proposal maintained the fundamental approach of 

the March 2011 final rule, but the proposed criterion better 

reflected the EPA’s intent to allow certain flexibilities when 

making contaminant comparisons. 

First, the proposal replaced “contaminants” with the phrase 

“contaminants or groups of contaminants” to clarify that, when 

deciding how to compare contaminants between NHSMs and 

traditional fuels, persons do not have to make comparisons on a 

contaminant-by-contaminant basis in all cases. When technically 

reasonable, comparisons may be made on a group of contaminantsby-group of contaminants basis.

The December 2011 rule also proposed to codify language 

from the preamble to the March 2011 final rule clarifying that 

when selecting which traditional fuel(s) a unit is designed to 

burn, persons are not limited to the traditional fuel the unit 
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is currently permitted to burn. Persons may choose any 

traditional fuel the unit can burn or does burn, whether or not 

it is permitted to burn such fuel. 

In addition, the proposed regulations included text 

confirming that, when comparing contaminant levels between NHSMs 

and traditional fuels, persons are not limited to data from the 

specific traditional fuel being replaced. National surveys of 

traditional fuel contaminant levels are one example of another 

acceptable data source. Neither the March 2011 final rule nor 

the December 2011 proposed rule required persons to compare 

contaminants in their NHSM to contaminants in the specific 

traditional fuel source they burn (or would otherwise burn). As 

an example, the proposal noted that persons who would otherwise 

burn coal may use any as-burned coal available in coal markets 

in making a comparison between the contaminants in their NHSM 

and the contaminants in coal—they are not limited to coal from a 

specific coal supplier they have used in the past or currently 

use. 

Finally, the proposed regulations included text confirming 

that, when comparing contaminant levels between NHSMs and 

traditional fuels, persons are not limited to comparing average 

concentrations. Traditional fuel contaminant levels can vary 

considerably and the full range of contaminant values may be 

used.
Page 152 of 319

Two other issues arose prior to the December 2011 proposed 

rule that, while not leading to specific regulatory changes in 

the proposal, still merited a discussion in the proposal. The 

first issue was that contaminant legitimacy criterion 

determinations do not require testing contaminant levels, in 

either the NHSM or an appropriate traditional fuel. Persons can 

use expert or process knowledge to justify decisions to either 

rule out certain constituents or determine that the NHSM meets 

the contaminant legitimacy criterion. The second issue was that 

persons may use data from a group of similar traditional fuels 

for contaminant comparisons, provided the unit could burn each 

traditional fuel. The idea grows from the “designed to burn” 

concept explained in the March 2011 final rule and codified in 

today’s final rule, and it allows a person with a unit that can 

or does burn similar traditional fuels (e.g., anthracite, 

lignite, bituminous and sub-bituminous coal) to group those 

traditional fuels when making contaminant comparisons. 

The EPA believes that comments have not changed the basis 

for making the decisions to expressly allow grouping of 

contaminants, to interpret “designed to burn” to mean can burn 

or does burn regardless of permit status, and to affirm that 

persons can use ranges and national surveys of traditional fuel 

data when making contaminant comparisons between NHSMs and 

traditional fuels. Comments have also not changed the agency’s 
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basis for making the decisions that testing is not required and 

that persons can group similar traditional fuels for the 

purposes of contaminant comparisons. Thus, the EPA is adopting 

the reasoning from the proposal and revising the contaminant 

legitimacy criterion for NHSMs used as a fuel to incorporate 

these concepts. 

The EPA has decided, however, to make one modification to 

the proposed contaminant legitimacy criterion based on comments 

received and information in the rulemaking record. The final 

criterion issued today includes additional language clarifying 

the appropriate use of ranges when making contaminant 

comparisons between NHSMs and traditional fuels. To use the full 

range of contaminant values in traditional fuels, persons should 

also account for the variability in NHSM contaminant levels. 

Additional details and rationale for the proposed revisions 

concerning the grouping of contaminants, the meaning of designed 

to burn, and the use of ranges and traditional fuel data in 

making contaminant comparisons are discussed in section 

III.D.2.b, section III.D.2.c, and section III.D.2.d below. 

Additional reasoning for keeping the rule provisions as proposed 

and for any modifications to the proposed language are described 

in the responses to comments included in these sections.

a. General Comments on the Revised Contaminant Legitimacy 

Criterion
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The EPA is not responding to issues that the agency decided 

in the March 2011 rule and has not reopened for comment. 

Specifically, the agency has previously discussed and did not 

solicit comments in this rule on why the concept of legitimacy 

is important in determining whether a secondary material is 

genuinely recycled or is, in fact, discarded.31 The agency has 

also previously discussed and did not solicit comments in this

rule on why contaminant comparisons to traditional fuels are an 

appropriate and mandatory factor in determining legitimacy for 

NHSMs used as fuels in combustion units.32 The agency has also 

previously discussed and did not solicit comments in this rule 

on why the “comparable to or lower than” standard is more 

appropriate than the “not significantly higher than” standard.33

The agency has also previously discussed that the NHSM Rule 

differs from the DSW Rule in that it is tailored specifically 

for application to NHSMs used in combustion units.34

Comment: Industry commenters overwhelmingly supported the 

proposed revisions to the contaminant legitimacy criterion, 

stating that the revisions would help provide regulatory 

certainty and give the regulated community more confidence in 

their self-determinations. 

 

31 See 75 FR 31870.

32 See 75 FR 31871-31872. See also, 76 FR 15524-15525.

33 See 75 FR 31872. See also, 76 FR 15523.

34 See 75 FR 31870.
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Environmental groups, on the other hand, expressed concern 

that the combination of flexibilities present in the proposed 

revisions to the contaminant legitimacy criterion will allow 

facilities to compare contaminant levels in C&D debris and other 

wood waste to the highest contaminant levels found in coal, even 

if the facility is not permitted to burn coal. They believed 

that this should not be permitted and argued that C&D wood 

should not contain contaminant levels higher than found on 

average in virgin biomass.

State comments were mixed, with one commenter supporting 

the proposed revisions and another commenter expressing concern 

that the revisions would weaken the states’ permitting 

authorities and create an incentive for combustors to burn 

dirtier traditional fuels.

Response: The EPA has decided to retain the concepts 

proposed to the contaminant legitimacy criterion because these 

changes more accurately reflect the EPA’s intent under the March 

2011 final rule. The agency maintains that these concepts are 

reasonable and provide a necessary degree of certainty for 

persons seeking to comply with the rule. This is explained in 

more detail in sections III.D.2.b (groups of contaminants), 

III.D.2.c (meaning of designed to burn), and III.D.2.d 

(allowable contaminant comparisons) of this preamble. 
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At the same time, comments from both industry and 

environmental groups have highlighted, in the agency’s opinion, 

a need for additional clarity in the regulatory text on the 

appropriate use of ranges when making contaminant comparisons 

between NHSMs and traditional fuels. Accordingly, the EPA has 

made a minor adjustment to the criterion to ensure that ranges 

are not used inappropriately in contaminant comparisons (i.e., 

the highest traditional fuel contaminant values should not be 

compared to average NHSM contaminant values). See section 

III.D.2.d of this preamble for a more detailed description of 

this specific change to the contaminant legitimacy criterion. 

The agency disagrees with state concerns that the NHSM rule 

will weaken the states’ permitting authorities. State permitting 

authorities must still approve permit changes and this final 

rule does not affect discretion of the permitting authorities in 

acting on requests for permit modifications. The agency also 

disagrees with state concerns that the NHSM rule will create an 

incentive for combustors to burn dirtier traditional fuels. The 

EPA understands how restricting contaminant comparisons to 

traditional fuels the unit currently burns could provide an 

incentive for the facility to burn traditional fuel with high 

contaminant levels. When facilities do not actually have to burn 

that traditional fuel to make comparisons, however, that 

incentive is effectively removed. 
Page 157 of 319

Comment: One commenter requested that the proposed 

revisions to the contaminant legitimacy criterion be added to 

each option for demonstrating that NHSMs are non-wastes when 

used in combustion units, whether it is the on-site 

documentation, the EPA petition process or the categorical nonwaste determination process proposed in 40 CFR 241.4. 

Response: Revisions to the contaminant legitimacy criterion 

codified today in 40 CFR 241.3(d)(1) apply to all options for 

demonstrating that a NHSM is not a solid waste when used as a 

fuel in a combustion unit. The revised legitimacy criterion is 

embedded in the self-implementing options outlined in 40 CFR 

241.3(b)(1) for use within the control of the generator and 40 

CFR 241.3(b)(4) for NHSMs that are processed and then used in a 

combustion unit. The revised legitimacy criterion is also 

embedded in the optional EPA petition process outlined in 40 CFR 

241.3(c). The revised legitimacy criterion is also referenced as 

a factor to be considered in the categorical non-waste 

determination process outlined in 40 CFR 241.4.

Comment: Several commenters expressed concern that the 

proposed revisions to the contaminant legitimacy criterion, 

although an improvement over the 2011 Final NHSM Rule, may not 

provide the regulated community with enough information to be 

confident in their compliance status. Two commenters noted that 

the EPA has overlooked the analytical complexities inherent in 
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the contaminant legitimacy criterion and the many opportunities 

it creates for disagreement between facility operators and 

regional and state regulators. One of these commenters asked the 

EPA to both define the term ‘comparable’ and clarify sampling 

and analytical methodologies to be used when measuring 

contaminant levels. Other commenters advised the EPA to increase 

predictability as much as possible by developing a disciplined 

process for making contaminant comparisons and providing real 

time transparency for such decisions. 

Similarly, two commenters expressed concern that even after 

a source makes a fuel determination, the EPA could take a 

different view of the NHSMs and conclude that they were solid 

wastes. The risk sources face is noncompliance with the CAA and 

these commenters contended that the issue is too critical for 

the EPA to leave the contaminant legitimacy criterion so vague. 

Over time, as the EPA develops a record for decisions 

(particularly comparable contaminant determinations), one of 

these commenters urged the EPA to establish a database and 

immediately post determinations for other sources to review.

Other commenters supported the proposed revisions to the 

contaminant legitimacy criterion and indicated that they 

provided sufficient clarification. One commenter noted that 

changes to the language of the criterion and the additional 

clarification provided in the preamble to the December 2011 
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proposed rule provide key additional detail on making 

contaminant comparisons and allow additional flexibility where 

appropriate. The same commenter urged the EPA to maintain that 

flexibility if the agency develops additional guidance on making 

contaminant comparisons in the future. 

Response: The EPA has retained the approach included in the 

proposed rule that provides information on how contaminant 

comparisons can be made and the agency will continue to make its 

traditional fuel data and legitimacy determinations transparent 

through the EPA website.35

The agency recognizes the need for regulatory certainty, a 

need that has been addressed by revisions to the definition of 

contaminants and the contaminant legitimacy criterion in today’s 

final rule. Contaminants have been specifically listed, 

additional clarity on NHSMs/traditional fuel comparisons has 

been provided and several comparison methodologies have been 

provided in the preamble as examples that could be used by the 

regulated community. Comments from the regulated community have 

been supportive both of these changes and of the agency’s 

efforts to update traditional fuel data that can be used for 

 

35 The EPA maintains a NHSM webpage with current information on contaminant 

levels in traditional fuels, examples of legitimacy determinations and other 

information at http://www.epa.gov/epawaste/nonhaz/define/index. 
Page 160 of 319

contaminant comparisons.36 In addition, a number of 

interpretative letters have been written that address specific 

fact situations as presented by a specific facility and these 

letters have been posted on the EPA’s website. These letters 

serve as examples of acceptable ways to demonstrate legitimacy.

The EPA must balance the need for regulatory certainty, 

however, with the need for flexibility, which many commenters 

also believe is important. As the agency has previously 

discussed, the legitimacy criteria must be flexible enough to 

account for future changes in commodities, technologies, markets 

and fuel prices.37 Previous comments have stressed the preference 

for a qualitative approach, and the agency has agreed, noting 

that numerical specifications may be impractical due to the 

multiplicity of fuels and ingredients.38 The agency has also 

previously discussed that a numerical definition of ‘comparable’ 

would be impractical given differences in the typical 

concentration levels of various contaminants, choosing instead 

to offer several examples.39 While the agency will consider 

future guidance on contaminant comparisons, it has determined 

that no one approach is appropriate for every legitimacy 

determination given the variety of traditional fuels, NHSMs and 

 

36 Contaminant Concentrations in Traditional Fuels: Tables for Comparison, 

November 29, 2011, can be found at 

http://www.epa.gov/epawaste/nonhaz/define/index. 

37 See 75 FR 31870.

38 See 75 FR 31871.

39 See 76 FR 15524 and 15542.
Page 161 of 319

combustion units that currently exist and will likely increase 

in the future. 

Comment: One commenter noted that both the March 2011 NHSM 

final rule and the proposal implicitly place the burden on the 

combustion facility to determine if a fuel derived from NHSMs 

meets the legitimacy criteria. In the utility industry, the 

commenter explained, it is common practice for utilities to rely 

on fuel marketers to establish and verify fuel quality, and the 

regulatory burden on utilities combusting such secondary 

materials as fuels could be reduced if the EPA clarified the 

circumstances under which a facility would be entitled to rely 

on the fuel quality representations of its suppliers. The 

commenter suggested that the EPA clarify that a utility may rely 

in good faith on the representations of its suppliers that NHSMs 

meet the codified legitimacy criteria, or, alternatively, that 

utilities be required only to periodically test the quality of 

NHSM-derived fuels obtained from third parties to rely on their 

suppliers’ representations. 

Response: The EPA notes that while fuel suppliers may 

provide their customers with documentation supporting a 

legitimacy determination, persons who burn NHSMs are ultimately 

responsible for the materials burned at their units. As stated 

in the proposed rule, however, the agency adopts as its decision 

for this final rule that initial assessments would not need to 
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be repeated as long as the facility continues to operate in the 

same manner and use the same type of NHSM as when the original 

assessment was made.40

b. Grouping of Contaminants

The December 2011 proposed revision to the contaminant 

legitimacy criterion for NHSMs used as a fuel began with the 

following sentence: “The non-hazardous secondary material must 

contain contaminants or groups of contaminants at levels 

comparable in concentration to or lower than those in 

traditional fuel(s) which the combustion unit is designed to 

burn.” The phrase ‘or groups of contaminants’ was not present in 

the language from the March 2011 NHSM Final Rule but was 

included in the December 2011 NHSM Proposed Rule to clarify that 

groups of contaminants could be evaluated in determining whether 

a NHSM meets the contaminant legitimacy criterion. 

In particular, the proposed rule noted that groups of 

contaminants in NHSMs could be compared to similar groups in 

traditional fuels where the grouped contaminants shared physical 

and chemical properties that influence their behavior in the 

combustion unit prior to the point where emissions occur. 

Volatility, the presence of specific elements and compound 

structure were three such properties identified in the proposal 

and one approach to grouping contaminants was shown that 

 

40 See 76 FR 80481.
Page 163 of 319

included groups for TOX, nitrogenated HAP, VOCs, SVOCs, dioxins 

and furans, PCBs, PAHs and radionuclides. The agency also noted 

that persons may consider other groupings that they can show are 

technically reasonable.

Grouping of contaminants is a standard practice often 

employed by the agency as it develops regulations. In fact, the 

monitoring standards included in the CAA sections 112 and 129 

regulations also utilize the grouping concept and they apply to 

the same combustion units impacted by the NHSM rule (i.e., 

industrial, commercial and institutional boilers and process 

heaters and CISWI units). For example,

Volatile hydrocarbons and semi-volatile hydrocarbons can 

both be expected to result from incomplete combustion; 

therefore, the emission standards promulgated under the CAA 

regulations are grouped into one category: CO.41

Halogenated organics are expected to contribute to 

emissions of dioxin and acid gases (HCl and HF); therefore, 

the emission standards promulgated under the CAA are 

grouped into two categories: D/F and HCl.42

Nitrogenated compounds are expected to contribute to 

emissions of NOx; therefore, the emission standards 

promulgated under the CAA are grouped into one category: 

NOx.

43

In addition, a number of the seemingly “individual” 

pollutants listed in sections 112 and 129 of the CAA are 

actually classes of structurally-related compounds (e.g., PCBs, 

 

41 Area Source Boilers NESHAP, Major Source Boilers NESHAP, and Commercial and 

Industrial Solid Waste Incinerators NESHAP.

42 Major Source Boilers NESHAP and Commercial and Industrial Solid Waste 

Incinerators NESHAP.

43 Commercial and Industrial Solid Waste Incinerators: NESHAP.
Page 164 of 319

POM, D/F, cyanide compounds, cresols, glycol ethers, 

radionuclides, xylenes, antimony compounds, arsenic compounds, 

beryllium compounds and cadmium compounds).

All comments discussing the agency’s proposal to expressly 

allow the grouping of contaminants supported the agency’s 

position. Thus, the EPA is adopting the language from the 

proposal and revising the contaminant legitimacy criterion for 

NHSM used as a fuel to allow contaminants to be compared on a 

contaminant-by-contaminant basis or, where reasonable, on a 

group of contaminants-by-group of contaminants basis. Any 

additional reasoning for keeping the revision as proposed, 

without modification, is described in the responses to comments 

below.

Comment: In general, comments overwhelmingly supported the 

ability to group contaminants when making contaminant 

comparisons in accordance with the legitimacy criteria. 

Commenters stated that codification of this concept would 

provide regulatory certainty and allow for more meaningful 

comparisons, similar to the manner in which the EPA measures 

emissions at combustion units. Commenters noted that the ability 

to group contaminants will facilitate compliance because most 

existing test methods, including the EPA methods, call for the 

grouping of analytes. Commenters believed that the grouping 

concept is an appropriate mechanism to recognize the variability 
Page 165 of 319

in contaminant levels inherent in fuels. Commenters also 

appreciated the examples of appropriate contaminant groups 

provided in the proposed rule along with the ability to compare 

other technically reasonable groups (76 FR 80477-80480).

Two commenters stated that each mention of the word 

“contaminants” should be changed to “contaminants or groups of 

contaminants” in the regulatory text to further clarify that a 

comparison to groups of contaminants is intended. 

Response: The EPA has retained the language specifically 

allowing grouping in the contaminant legitimacy criterion for 

NHSMs used as a fuel. The EPA adopts the reasoning in the 

December 2011 rule as its final reasoning, as further supported 

with reasoning discussed in the comment responses below. While 

the EPA has retained the language allowing the grouping of 

contaminants, the agency does not consider it necessary to 

change every instance of “contaminant levels” and “contaminants” 

to “contaminants or groups of contaminants” in order to make it 

sufficiently clear that contaminant grouping is allowed. The 

agency also notes that not all contaminants are necessarily 

intended to be grouped, including individual elemental 

contaminants, asbestos, CO and phosphine.44

Comment: The ability to group metal contaminants was

suggested by several commenters. One commenter held that all 11 

 

44 See 76 FR 80478, Tables 7 and 8.
Page 166 of 319

metals should be specifically included as one group. Another 

commenter noted that with the exception of Hg, all metals should 

be grouped. Yet another commenter suggested that metals could be 

grouped into a volatile metals group and a non-volatile metals 

group. 

Response: First, we would note that the agency is not 

limiting groups to the specific approach suggested in the 

proposed rule—that is, the tables in the proposed rule suggest, 

but do not limit persons to, an approach, including groups for 

TOX, nitrogenated HAPs, VOCs, SVOCs, dioxins/furans, PCBs, PAHs 

and radionuclides, with other contaminants left to be evaluated 

on an individual contaminant-by-contaminant basis. Flexibility 

exists for persons to consider other appropriate groups that 

they can show are technically reasonable, with additional text 

in the proposal stating that other groups should share physical 

and chemical properties that influence behavior in the 

combustion unit prior to the point where emissions occur. 

Volatility, the presence of specific elements and compound 

structure are three such properties.45

However, we do not consider the grouping of total metals to 

be appropriate. Specifically, metals vary across all three 

parameters—volatility, the presence of specific elements and 

compound structure—that were discussed as appropriate to 

 

45 See 76 FR 80477.
Page 167 of 319

consider when constructing contaminant groups. First, many 

factors influence metal volatility in combustion units, and to 

the extent that trends in metal volatility have been recognized, 

a wide disparity exists between metals. Mercury, as one 

commenter noted, is highly volatile, more so than any other 

metals listed in the contaminants definition. Metals can be 

grouped into volatile, semi-volatile and low-volatile 

categories, but it is important to note that these distinctions 

can vary based on design differences in combustion units, 

operating temperatures, the physical form and species of the 

metal and the presence of chlorine.46,47 Second, each metal 

clearly contains different elements. Finally, each metal is 

already a group of any compound containing the particular 

element, encompassing a wide array of compound structures. In 

the absence of other suggested grouping criteria or information, 

the EPA does not consider total metals to be an appropriate 

group. 

Comment: One commenter provided a numerical example of VOC 

contaminant levels in fuel oils to illustrate the importance of 

grouping. The commenter cited the traditional fuel tables 

provided on the EPA website, stating that toluene and xylenes 

 

46 EPA. 2001. “Risk Burn Guidance for Hazardous Waste Combustion Facilities.” 

EPA530-R-01-001. July.

47 Clarke, L.B. and L.L. Sloss, 1992. “Trace Elements – Emissions from Coal 

Combustion and Gasification.” IEACR/49. IEA Coal Research, London. July. 
Page 168 of 319

are present in fuel oils at concentrations up to 380 ppm and 

3,100 ppm, respectively. If a NHSM had the concentrations 

reversed, explained the commenter (380 ppm xylene and 3,100 ppm 

toluene), the ability to group VOCs would then allow the NHSM to 

meet the contaminant legitimacy criterion. The commenter 

reasoned that this is appropriate because both toluene and 

xylenes are beneficial components of fuel.

Response: The EPA disagrees with this interpretation of the 

grouping concept. Unless concentration data for a group of 

contaminants (e.g., VOCs) come from the same fuel source, adding 

together the concentrations of individual constituents (e.g., 

toluene and xylene) within that group may yield a total 

concentration beyond what would be considered a normal part of a 

legitimate fuel. Using the example cited by the commenters, some 

fuel oils have been found to have up to 380 ppm toluene and 

other fuel oils have been found to have up to 3,100 ppm xylene. 

Because the toluene and xylene concentrations were taken from 

different fuel oils, however, this does not prove that a single 

fuel oil in existence actually has VOC levels as high as 3,480 

ppm (380 + 3,100). 

The agency notes that VOC levels higher than as 3,480 ppm,

have been found in fuel oil -- concentrations of one VOC alone 

(hexane)have been found as high as 10,000 ppm -- and the point 
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of this discussion is to clarify a methodology rather than a 

number for acceptable VOC levels in NHSMs.48

We would also note that while the agency considers VOCs to 

be an appropriate contaminant group to use when making 

contaminant comparisons, it does not base that decision on 

whether or not toluene, xylenes and other VOCs are “beneficial 

components of fuel.” The decision that toluene, xylene and other 

VOCs, which the agency notes are pollutants listed in CAA 

section 112(b), are an appropriate group is based on the fact 

that they share similar physical and chemical properties that 

influence their behavior in the combustion unit prior to the 

point where emissions occur. 

c. Meaning of Designed to Burn

The December 2011 proposed revision to the contaminant 

legitimacy criterion for NHSMs used as a fuel included the 

following statement: “In determining which traditional fuel(s) a 

unit is designed to burn, persons can choose a traditional fuel 

that can be or is burned in the particular type of boiler, 

whether or not the combustion unit is permitted to burn that 

traditional fuel.” The idea that “designed to burn” means “can 

burn or does burn” was included in preamble text to the March 

 

48 Contaminant Concentrations in Traditional Fuels: Tables for Comparison, 

November 29, 2011 can be found at 

http://www.epa.gov/epawaste/nonhaz/define/index. EPA intends to update this 

document as additional data becomes available, and if persons have data 

measuring traditional fuels for groups of VOCs, or for other contaminant 

groups, they are encouraged to provide the agency with such data.
Page 170 of 319

2011 final rule. The December 2011 rule proposed to include this 

concept, which is only applied under the NHSM rule to aid in the 

selection of appropriate traditional fuel(s) for contaminant 

comparisons, in regulatory language.

The March 2011 final rule explained that in determining 

which traditional fuel(s) the owner or operator of the boiler 

unit would make a comparison to with respect to contaminant 

levels, the agency would allow any traditional fuel(s) that can 

be or is burned in the particular type of boiler. The agency 

reasoned that this approach was the most appropriate since the 

NHSM would be replacing the use of particular type(s) of fuel 

that could otherwise be burned.49

The December 2011 proposal further explained that 

contaminants are compared between NHSMs and traditional fuels to 

assist in making a determination whether or not the NHSM is 

being discarded when combusted, not to regulate which 

traditional fuel a combustor should choose to burn. For the 

purposes of making a discard determination, the proposal 

reasoned that differentiating between “can burn” and “does burn” 

was not relevant.

The agency did note in the proposed rule, however, that for 

a unit to be able to burn a traditional fuel, it would need an 

appropriate feed mechanism (e.g., a way to load solid fuel of a 

 

49 See 76 FR 15542.
Page 171 of 319

particular size into the unit) and the ability to adjust 

physical parameters to ensure spatial mixing and flame stability 

per unit specifications.

Because most combustion units can burn different—but 

related—traditional fuels, the agency discussed in the proposal 

that broad groups of similar traditional fuels may be used when 

comparing contaminants. The most common traditional fuel 

categories burned at major source boilers are coal, wood, oil 

and natural gas, as evidenced by data submitted to the EPA’s 

OAQPS.50,51

To further clarify the impact of the proposed “designed to 

burn” language on contaminant comparisons, potential categories 

for coal, wood and oil were further described in the proposal. A 

coal group was proposed that could include data on anthracite, 

lignite, bituminous and sub-bituminous coal. A wood or biomass 

group was proposed that could include data on unadulterated 

lumber, timber, bark, biomass and hogged fuel. An oil group was 

proposed that could include data on fuel oils 1-6, diesel fuel, 

 

50 EPA, Office of Air Quality Planning and Standards (OAQPS), Emissions 

Database for Boilers and Process Heaters Containing Stack Test, CEM & Fuel 

Analysis Data Reported Under ICR No. 2286.01 and ICR No. 2286.03 (Version 7). 

December 2011. http://www.epa.gov/ttn/atw/boiler/boilerpg.html#TECH.

51 The fuel analysis information in this OAQPS database is one example of a 

“national survey” of traditional fuel information, as referenced in the final 

contaminant legitimacy criterion issued today at §241.3(d)(1)(iii).
Page 172 of 319

kerosene and other petroleum based oils.52 In cases where a unit 

can burn traditional fuels from several categories, such as a 

boiler that can burn coal or biomass, the proposal noted that 

contaminant comparisons could be made using data from either 

fuel category.

The ability to compare contaminants in a NHSM, under the 

NHSM rule, to contaminants in any traditional fuel that could be 

burned does not change the fact that once burning occurs, 

emissions standards are determined under the Boiler MACT or 

CISWI rule by the particular fuel (or fuel blend) that is

burned. Whether each rule focuses on what ‘could be burned’ or 

on what ‘is burned’ is determined by the rule’s purpose and the 

order in which decisions must be made. Together, these factors 

explain why the NHSM, Boiler MACT, and CISWI rules take 

different approaches to account for individual combustion units 

that burn multiple fuels.

Specifically, the NHSM rule must first determine which 

NHSMs can be burned in CAA section 112 units (i.e., boilers) and 

which can only be burned in CAA section 129 units (i.e., 

incinerators). When making such a waste or non-waste 

determination, the NHSM rule cannot always predict what fuel 

would otherwise be burned (multiple options may exist). 

 

52 EPA has determined that an oil group should not include unrefined crude oil 

or gasoline, as neither is typically burned in combustion units subject to 

the CAA sections 112 or 129 standards.
Page 173 of 319

Accordingly, the rule allows contaminant comparisons to be made 

to any traditional fuel the unit could burn. The Boiler MACT or 

CISWI rule must then determine how to regulate emissions from 

the unit, by which point it is clear what fuel is actually being 

burned. Accordingly, these rules can and do establish 

subcategories of units, each with different emissions standards, 

based on both boiler design and the particular fuel/material 

driving emissions performance. When units switch from one fuel 

to another—from what defines one subcategory to what defines 

another subcategory—the emissions standards change. Units 

burning a blend of fuels would be in one of the subcategories 

depending on that blend, and therefore, subject to the standards 

of that category. 

The EPA has considered the comments received, as explained 

below, but has not changed the basis for its interpretation of 

the “designed to burn” concept. Thus, the EPA is adopting the 

language from the proposal and revising the contaminant 

legitimacy criterion for NHSMs used as a fuel to allow persons 

making contaminant comparisons to choose a traditional fuel that 

can be or is burned in the particular type of boiler, whether or 

not the combustion unit is permitted to burn that traditional 

fuel. Any additional reasoning for keeping the revision as 

proposed, without modification, is described in the responses to 

comments below.
Page 174 of 319

Comment: Industry commenters generally supported the 

agency’s proposal to codify the previously stated meaning of 

“designed to burn” within the contaminant legitimacy criterion 

for NSHMs used as fuels. These commenters welcomed the 

regulatory certainty provided by the revision and described it 

as a practical and appropriate recognition that some units can 

burn multiple traditional fuels. 

Environmental groups, on the other hand, expressed concern 

that the proposed definition of designed to burn would allow 

contaminants in C&D wood to be compared to those in coal instead 

of virgin wood. 

One state commenter also expressed concern that allowing 

comparisons to any fuel the unit could burn, including fuels 

they are not permitted to burn, would weaken the states’ 

permitting authorities and create an incentive for combustors to 

burn dirtier traditional fuels so that they could compare NHSMs 

to fuels with higher contaminant levels. An industry commenter 

also mentioned that such an approach would reward facilities 

that burn dirtier fuel and suggested that the agency remove the 

entire “designed to burn” concept from the rule. 

Response: Based on a review of the comments, the EPA has 

retained the proposed revision to the contaminant legitimacy 

criterion for NHSMs used as fuels clarifying that, for the 

purpose of determining traditional fuel(s) to which a NHSM may 
Page 175 of 319

be compared, the meaning of “designed to burn” may be broadly 

interpreted to include any traditional fuel that could be 

burned, regardless of facility permit status. The agency 

disagrees that this interpretation of “designed to burn” would 

incentivize the burning of dirtier fuels or weaken the states’ 

permitting authorities. 

The EPA finds that allowing combustors to compare NHSMs to 

any traditional fuel a unit can or does burn is both practical 

and appropriate under the statutory definition of solid waste. 

Although not all combustion units can burn multiple traditional 

fuels, some units can and, indeed, do rely on different fuel 

types at different times based on availability of fuel supplies, 

market conditions, power demands and other factors. Under these 

circumstances, it would be arbitrary to restrict the combustion 

for energy recovery of NHSMs with contaminant levels comparable 

to or lower than that of one traditional fuel the unit could 

choose to burn solely because contaminant levels are higher than 

that of a second traditional fuel the unit could also choose to 

burn if fuel supplies, market conditions, power demands, or 

other factors change. Such an approach would be impracticable 

and not consistent with the agency’s intent. It would also be 

inconsistent with the concept of discard, since a facility 

burning a NHSM with the same contaminants as another fuel it 
Page 176 of 319

could also be burning should not be considered to discard that 

NHSM based on its contaminant levels.

The agency has also determined that restricting comparisons 

to traditional fuels the unit is permitted to burn is 

unnecessary. The fact that a facility is not currently permitted 

to burn a particular traditional fuel does not mean it could not 

be permitted to burn that traditional fuel in the future. For 

this reason, we do not believe it is reasonable to limit the 

comparison to permitted traditional fuels. Furthermore, such a 

restriction could have the unintended consequence of combustion 

facilities across the country seeking permit modifications 

solely to facilitate contaminant comparisons for this rule. 

State permitting authorities must still approve permit changes 

and this final rule does not affect the discretion of the 

permitting authorities in acting on requests for permit 

modifications.

In addition, the EPA has determined that restricting 

contaminant comparisons to traditional fuels the unit currently

burns could provide an incentive for the facility to burn 

traditional fuel with high contaminant levels. When facilities 

do not actually have to burn that traditional fuel to make 

comparisons, that incentive is effectively removed. 

Comment: One commenter asked the agency to specifically 

acknowledge that certain categories of boilers are designed to 
Page 177 of 319

burn a variety of fuels, noting that stoker boilers, fluidized 

bed combustors and boilers with suspension burners, in 

particular, should be on such a list.

Response: The agency has decided not to specifically list 

which combustion units are designed to burn which fuels for two 

reasons. First, the owner or operator of a combustion unit has a 

better understanding than the agency does of what that 

particular unit is designed to burn. Second, the agency is 

concerned that creating such a list will limit the flexibility 

of combustors with other types of units.

Comment: One commenter noted that if the EPA considers it 

inappropriate to compare liquid fuels to solid fuels, the agency 

offers no justification for its position. The commenter argued 

that liquid to solid comparisons should be allowed because most 

cement kilns and many other industrial furnaces have the 

capacity to burn either solid or liquid fuels. The commenter 

described the December 2011 proposed rule as ambiguous with 

regard to this issue and recommended that if a combustion unit 

is designed to burn both a liquid fuel and a solid fuel, then 

the liquid to solid comparison should be “appropriate.” 

Response: EPA agrees with the commenter that if a unit can 

burn both a liquid traditional fuel and a solid traditional 

fuel, then comparison of an NHSM to either fuel would be 

appropriate. The revised contaminant legitimacy criterion 
Page 178 of 319

clarifies how the “designed to burn” concept may be interpreted 

for the purposes of determining traditional fuel(s) to which a 

NHSM may be compared, and the Agency has determined that this 

revision is sufficient to allow appropriate comparisons to be 

made between solid NHSMs and liquid traditional fuels, and vice 

versa. The agency does not expect these circumstances to hold 

true for all combustion units, however, and reiterates that this 

would only be appropriate when the unit can in fact burn 

multiple traditional fuels used to make such comparisons.

Comment: Several industry commenters addressed the topic of 

what it means to be able to burn a traditional fuel in a 

combustion unit. The preamble to the recent proposed rule noted 

that combustion units would need an appropriate feed mechanism, 

as well as the ability to ensure the fuel is well mixed and keep 

flame temperatures within unit specifications, to be able to 

burn a traditional fuel.53 Two commenters opposed the agency’s 

interpretation of what it means to be able to burn a traditional 

fuel in a combustion unit, stating that the agency provides no 

explanation of why feed mechanisms are relevant to whether or 

not a unit can burn a particular fuel. Both commenters also 

noted that when NHSMs are used as a fuel in combustion units, 

the focus on what a unit is “designed to burn” in the first 

place is irrelevant to whether discard is occurring. Another 

 

53 See 76 FR 80481.
Page 179 of 319

commenter explained that the same exact material could then be a 

solid waste in one case and a fuel in another case, depending on 

who is using the material.

A third commenter supported the agency’s interpretation of 

what ‘can burn’ means, stating that the fate and emissions of a 

contaminant, whether it is contained in a traditional fuel or a 

material being considered for legitimacy, are as dependent on 

the design of the combustion unit as they are on the fuel 

matrix. The commenter explained further that units should be 

considered able to burn several types of fuels as long as each 

type is within the design criteria of the feed system, the 

combustion chamber and any downstream pollution control device.

Response: The EPA disagrees with those commenters 

questioning the relevance of what fuels combustion units are 

designed to burn in the context of the legitimacy criteria. If a 

NHSM does not contain contaminants at levels that are comparable 

to or lower than those found in any traditional fuel that a 

combustion unit could burn, then it follows that discard could 

be occurring if the NHSM were combusted. Whether contaminants in 

these cases would be destroyed or discarded through releases to 

the air, they could not be considered a normal part of a 
Page 180 of 319

legitimate fuel and the NHSM would be considered a solid waste 

when used as a fuel in that combustion unit.54

The reason we analyze what a unit is designed to burn is to 

decide the traditional fuel(s) to which contaminants should be 

compared. This comparison is then used as an aid to decide 

whether the NHSM is being legitimately used as a fuel or whether 

excess contaminants show that the burning is waste treatment. If 

a facility compared contaminants to a traditional fuel it cannot 

burn and that fuel is highly contaminated, a facility would then 

be able to burn excessive levels of waste components in NHSMs as 

a means of discard. Regardless of any fuel value in the 

material, it would be a waste.

Once this concept is established, certain factors are 

relevant to how we decide what a facility is designed to burn. 

The ability to burn a fuel in a combustion unit does have a 

basic set of requirements, the most basic of which is being able 

to get the material into the combustion unit. The agency 

reaffirms in today’s final rule its interpretation from the 

proposal that to be able to burn NHSMs, a combustion unit should 

also be able to ensure the material is well mixed and maintain 

temperatures within unit specifications. Without these basic 

limits, there would be no point in distinguishing between fuels 

a unit is or is not “designed to burn,” and every combustion 

 

54 See 76 FR 15523.
Page 181 of 319

unit would be considered “designed to burn” any combustible 

material. Clearly, that is not the agency’s intent. As 

illustrated by one of the commenters, when a unit cannot burn a 

fuel according to its own design specifications, excess air 

pollutants form and are likely to be discarded as emissions. 

Thus, the agency acknowledges that whether or not a NHSM is a 

waste may depend on the unit burning the material.

Comment: One commenter asked for clarification on the issue 

of unit modifications. If a boiler hypothetically could be 

modified in any way to combust a different traditional fuel, the 

commenter noted, then a comparison to that fuel should be 

permissible to demonstrate that the NHSM is not a waste.

Response: The EPA disagrees with this comment. As long as 

the modification remains hypothetical in nature, it stands to 

reason that the unit cannot yet burn the additional traditional 

fuel and the only reason it is comparing a NHSM to the dirtier 

fuel is to allow more waste input into the combustion unit. 

However, if the unit is actually modified to accept additional 

types of traditional fuels, then the owner or operator of the 

combustion unit can consider those traditional fuels in 

evaluating the NHSM for the contaminant legitimacy criterion. In 

this situation, such behavior shows that the combustor is 

serious about burning the other fuel and is willing to make the 
Page 182 of 319

investment so that it can be burned properly instead of simply 

trying to gain comparison to a dirtier material. 

Comment: In the proposed rule, EPA specifically addressed used 

oil stating: “Used oil is a special case and does not need to 

undergo the contaminant comparison. If it meets the 

specifications in 40 CFR part 279.11, it is a traditional fuel. 

If it does not meet the specifications (i.e., it is ‘‘off-spec’’ 

oil), it is a solid waste under the 2011 NHSM final rule.” 76 FR 

80481, fn. 44. Some commenters argued that off-spec used oil 

fuel, however, could satisfy all of EPA’s legitimacy criteria, 

including a contaminant comparison with coal, a traditional 

fuel. Thus, if a combustion unit is “designed to burn” both coal 

and oil, the facility should be able to use coal as the 

traditional fuel for the purposes of determining whether the 

contaminants are comparable—even when the NHSM at issue is offspec used oil, as defined in 40 CFR part 279.11.

Response: The Agency agrees with the commenter that 

contaminants in off-spec used oil burned for energy recovery in 

facilities that are designed to burn coal may be compared to 

coal for purposes of determining whether the off-spec used oil 

is a waste or non-waste product fuel. Accordingly, for purposes 

of waste/non-waste determinations, coal or oil, including onspec used oil can be used as the traditional fuel identified for 

comparison of contaminants to meet the legitimacy criterion for 
Page 183 of 319

units designed to burn both fuels. Some combustion units are 

designed to burn multiple fuels, such as both coal and oil, 

including on-spec used oil. Under these circumstances, the 

Agency agrees that the rules allow the comparison of contaminant 

levels to either traditional fuel. That is, to be designated as 

a non-waste, the off-spec used oil contaminant levels must be 

comparable to or lower than coal when coal is the traditional 

fuel used for comparison. 

EPA no longer finds, as stated in Footnote 44 of the 

proposed rule, that off-spec used oil is always a waste for 

facilities that are designed to burn coal. Off-spec used oil 

continues to be a waste, however, for facilities that are not 

designed to burn coal because off-spec used oil contains 

contaminant levels that are not comparable to on-spec used oil. 

EPA also notes that in the preamble to the March 2011 rule (p. 

15506), the Agency specifically rejected the comparison of offspecification used oil contaminants to coal. That discussion, 

however, was in the context of a general contaminant comparison 

for units that burn only fuel oil. Coal may not be the 

comparison material for all off-specification used oil, but only 

for those facilities that are designed to burn coal as provided 

in the definition of this rule. Finally, we want to make clear 

that EPA has not modified the part 279 regulations for 

management of used oil, and thus, burning of off-spec used oil 
Page 184 of 319

for energy recovery is still subject to those rules, including 

the requirement that off-spec used oil can only be burned in 

certain units (see 40 CFR 279.61(a)).55 

Comment: Commenters argue that the EPA has not adequately 

addressed how units designed to burn only NHSMs are to comply 

with the contaminant legitimacy criterion. The commenters 

explained that, under the rule structure as proposed, a NHSM may 

be classified as a waste simply due to a lack of a traditional 

fuel for comparison purposes. Comments acknowledge that the 

agency discussed the issue in the preamble to the proposed rule 

but the commenters disagree that the discussion provided any 

solution. Finally, commenters specifically requested that the 

EPA acknowledge the fact that a combustor designed for a 

particular NHSM fuel is dispositive that the NHSM is being 

legitimately burned for energy recovery. 

Response: The EPA disagrees with the assertion that the 

agency has failed to provide a solution for units designed only 

to burn NHSMs. The EPA also disagrees with the assertion made by 

commenters that the fact that a combustor has designed a 

 

55 Off-specification used oil can only be burned in the following types of 

units: (1) industrial furnaces, as defined in 40 CFR 260.10; (2) the 

following boilers, as defined in 40 CFR 260.10—industrial boilers located on 

the site of a facility engaged in a manufacturing process where substances 

are transformed into new products, including the component parts of products, 

by mechanical or chemical processes, utility boilers used to produce electric 

power, steam, heated or cooled air, or other gases or fluids for sale, and 

used oil fired space heaters provided that the burner meets the provisions of 

40 CFR 279.23; and (3) hazardous waste incinerators subject to regulation 

under subpart O of 40 CFR parts 264 or 265. 
Page 185 of 319

combustion unit for a particular NHSM fuel is dispositive that 

the NHSM is being legitimately burned for energy recovery.

The EPA acknowledges and is aware of units built 

specifically to burn NHSMs. One example is facilities built to 

burn resinated wood. The EPA notes that units built to burn such 

NHSMs are likely to be able to burn similar traditional fuels. 

Using the example of units built to burn resinated wood, the EPA 

considers it reasonable to assume that these units could also 

burn clean wood and, therefore, could make comparisons to that 

traditional fuel. The agency also notes that is it not aware of 

any units—and commenters have not identified any such units—that 

can burn only NHSMs.

The EPA has nonetheless provided what it considers to be a 

reasonable solution. As explained in the preamble to the 

proposed rule, the EPA advises combustors faced with such a 

situation to compare solid NHSMs to solid traditional fuels, 

such as coal or biomass, liquid NHSMs to liquid traditional 

fuels, such as oil, and gaseous NHSMs to gaseous traditional 

fuels, such as natural gas.56 In light of the explanation of 

“designed to burn” codified in the final contaminant legitimacy 

criterion, as well as industry comments that many combustion 

units can burn multiple types of fuel, the agency believes that 

its suggested approach adequately addresses the issue.

 

56 See 76 FR 80481.
Page 186 of 319

Finally, the EPA acknowledges that combustion units can and 

have been designed specifically to burn NHSMs and that such 

units can recover energy. The agency notes, however, that 

persons can and have also designed incinerators to dispose of 

certain waste materials and that such units can also recover 

energy. The agency, therefore, does not consider it dispositive 

that if combustion units are designed to burn a specific 

material, that material must be a legitimate non-waste fuel. 

d. Contaminant Comparisons Allowed

The proposed revision to the contaminant legitimacy 

criterion for NHSMs used as a fuel included the following 

statement: “In comparing contaminants between traditional 

fuel(s) and a non-hazardous secondary material, persons can use 

ranges of traditional fuel contaminant levels compiled from 

national surveys, as well as contaminant level data from the 

specific traditional fuel being replaced.” The March 2011 final 

rule did not discuss the use of ranges when evaluating 

contaminant data, nor did it discuss the use of traditional fuel 

data from national surveys. 

The December 2011 proposed rule included these concepts to 

clarify that persons are not required to adhere to a single 

comparison methodology, nor are they required to compare 

contaminants in their NHSMs to contaminants in the specific 

traditional fuel source they burn (or would otherwise burn). In 
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both instances, the additional language clarifies, but does not 

change the intent, of the March 2011 final rule.

Regardless of the specific methodology chosen, a comparison 

will have to be made for each contaminant or group of 

contaminants between the NHSM and a traditional fuel or 

traditional fuel group. Generators or combustors can use either 

traditional fuel data collected by the EPA or their own data for 

traditional fuel comparison values.57 Generators or combustors 

are responsible, however, for either providing NHSM comparison 

values in cases where testing is conducted. Examples of 

acceptable NHSM data could include both laboratory test results 

from a specific generator or combustor and industry-recognized 

values provided by a national trade organization.

Given data for a particular traditional fuel, the EPA noted 

in the proposal that many combustors would choose to base the 

traditional fuel comparison value on the upper end of its 

statistical range and that this approach was reasonable. 

Anything less could result in “traditional fuel” samples being 

considered solid waste if burned in the very combustion units 

designed to burn them—not the agency’s intent in the March 2011 

final rule.58 Given that selection (i.e., the range for 

 

57 The EPA maintains an NHSM webpage with current information on contaminant 

levels in traditional fuels, examples of legitimacy determinations, and other 

information at http://www.epa.gov/epawaste/nonhaz/define/index.

58 Traditional fuels, as defined in §241.2, are not required to meet the 

legitimacy criteria, and this scenario is only used to explain the logic 
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traditional fuel contaminant values), the agency noted that 

acceptable NHSM comparison values would include the upper end of 

a statistical range, a calculation involving the mean and 

standard deviation or perhaps a single data point in situations 

where data are limited. The proposal reasoned that it would not 

be appropriate to compare an average NHSM contaminant value to 

the high end of a traditional fuel range, as the existence of an 

average implies multiple data points from which a more suitable 

statistic (e.g., range or standard deviation) could have been 

calculated.

If each NHSM comparison value is comparable to or lower 

than its corresponding traditional fuel value, the material 

would be considered to meet the contaminant legitimacy 

criterion. An initial assessment would not need to be repeated, 

explained the proposal, provided the facility continues to 

operate in the same manner and use the same type of NHSMs as 

when the original assessment was made. 

Despite presenting several approaches for calculating NHSM 

comparison values, such as the upper end of a statistical range 

or a calculation involving the mean and standard deviation, the 

proposal did not preclude other reasonable methodologies. In the 

context of an inspection or enforcement action, the agency will 

 

behind basing a traditional fuel comparison value on the upper end of a 

statistical range.
Page 189 of 319

evaluate the appropriateness of alternative methodologies and 

data sources on a case-by-case basis when determining whether 

the contaminant legitimacy criterion has been met.

The EPA noted in the proposal that contaminant testing is 

not required and that process knowledge may be sufficient for 

particular contaminants in particular NHSMs. Even when 

analytical testing is not necessary, the EPA’s regulations 

governing recordkeeping for units subject to emissions standards 

for boilers and process heaters issued pursuant to CAA section 

112 require keeping a record to document the basis of non-waste 

determinations under the part 241 criteria (including the 

contaminant legitimacy criteria). See 40 CFR 40 CFR 

63.11225(c)(2)(ii) for area source boilers and 40 CFR 40 CFR 

63.7555(d)(2) for major source boilers.

The EPA believes that the comments have not changed the 

basis for its decision to allow the use of ranges and surveys of 

traditional fuel contaminant levels. Nor have comments changed 

the agency’s position that similar traditional fuels may be 

grouped for comparison purposes and that testing is not required 

in all cases. Thus, the EPA is adopting the reasoning from the 

proposal and adjusting the contaminant legitimacy criterion 

accordingly for NHSM used as a fuel. 

The EPA has decided, however, to make a modification to the 

regulatory language of the December 2011 proposed rule based on 
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comments received. The final criterion issued today includes 

additional language clarifying the appropriate use of ranges 

when making contaminant comparisons between NHSMs and 

traditional fuels. Consistent with the rationale provided in the 

preamble to the proposed rule, additional language now states 

that in order to use the full range of contaminant values in 

traditional fuels, persons should also account for the 

variability in NHSM contaminant levels. Any additional reasoning 

for finalizing the revision with or without suggested 

modifications is described in the responses to comments below.

Comment: Industry comments supported the proposed changes 

expressly allowing the use of ranges and national surveys of 

traditional fuel data, as did one state comment. One commenter 

stated that these changes provide a more practical approach to 

meeting the contaminant legitimacy criterion that recognizes the 

inherent variation of contaminants in NHSMs and traditional 

fuels. Several commenters supported the use of ranges by 

repeating the EPA’s rationale from the proposal that using 

anything lower would logically result in a determination that 

some traditional fuels should not be burned in combustion units 

designed to burn those fuels. Another commenter stated that 

these clarifications describe appropriate methods of handling 

data that are naturally variable and will result in fewer nonwaste materials being arbitrarily identified as wastes. 
Page 191 of 319

Environmental groups did not comment on the use of national 

surveys of traditional fuel data, but they opposed the use of 

ranges to evaluate contaminants, expressing concern that C&D 

wood contaminant levels would be compared to the highest

contaminant levels for coal. These commenters suggested that 

averages or medians be used instead. 

Response: Based on our review of the comments received, the 

EPA is retaining the approach outlined in the proposed rule to 

expressly allow the use of ranges and traditional fuel data from 

national surveys. As discussed in the proposed rule, the EPA 

considers it reasonable to allow combustors to use the range of 

contaminant levels present in traditional fuels because anything 

less could result in “traditional fuel” samples being considered 

solid waste if burned in the very combustion units designed to 

burn them. For this reason, the agency disagrees with comments 

stating that combustors should be limited to use of the average 

or median concentrations.

The EPA acknowledges that the revisions adopted as final in 

today’s rule would allow C&D wood contaminant levels to be 

compared to the highest contaminant levels for coal. The 

commenters do not specify, however, what C&D wood contaminant 

levels (averages or ranges) they are concerned would be compared 

to the highest levels in coal. The agency points out that the 

proposed revisions were not intended to allow average C&D wood 
Page 192 of 319

contaminant levels to be compared to the highest levels in coal. 

In light of the concerns expressed by these commenters, the EPA 

has modified the proposed language to provide additional 

assurance that such average-to-maximum comparisons, which the 

agency has already determined are inappropriate, will not be 

allowed under today’s final rule. The EPA has decided that such 

comparisons are inappropriate because, following the logic 

stated in the March 2011 final rule, average-to-maximum 

comparisons do not demonstrate that contaminants in these cases 

could be considered a normal part of a legitimate fuel and are 

not being discarded.59

Today’s final criterion makes clear that the full range of 

traditional fuel contaminant values can only be used if persons 

also consider some measure of variability in the NHSM 

contaminant data. This will help to ensure that average to 

maximum comparisons will not be used to justify the combustion 

of NHSMs as non-waste fuels.

Comment: Industry comments supported the concept discussed 

in the proposed rule that the contaminant legitimacy criterion 

does not require the testing of contaminant levels in NHSMs in 

all cases. The proposal noted that persons can instead use 

expert or process knowledge to justify decisions to rule out 

certain constituents. The proposal also noted that initial 

 

59 See 76 FR 15523.
Page 193 of 319

assessments would not need to be repeated, provided the facility 

continues to operate in the same manner and use the same type of 

NHSMs as when the original assessment was made. One commenter 

asked the EPA to confirm these statements, explaining that this 

policy will result in fewer NHSMs being arbitrarily identified 

as wastes. Another commenter stated that the flexibility 

provided by this policy will help ensure that regulated entities 

with varying levels of sophistication can better document that 

their NHSMs are non-waste fuels.

Environmental groups, on the other hand, commented that the 

EPA must require testing for contaminants, citing the extremely 

variable nature of C&D wood as a problem. Commenters expressed 

concern that a large amount of material is going to be generated 

as abandoned and foreclosed housing is torn down, and the 

potential for liberating vast amounts of lead and other urban 

toxics, to say nothing of arsenic and chromium from pressuretreated wood, has never been higher.

Response: Based on a review of the comments received, the 

EPA is maintaining its position that contaminant testing is not 

required in all situations. Requiring testing in some situations 

is unnecessary. Where a NHSM generator, processor or combustor 

knows a contaminant will either not be present or be present at 

a level below that in the appropriate traditional fuel or 

traditional product, the agency believes it is a reasonable and 
Page 194 of 319

practical policy to allow persons to rely on either process 

knowledge or previous testing of the same material. 

The agency notes that there will be instances where testing 

is conducted and comparisons will have to account for the 

variability of contaminant levels in NHSMs, including lead 

concentrations in C&D wood. The agency also notes that today’s 

final rule does not change its previously stated position that 

chromated copper arsenate-treated wood (CCA wood) would likely 

have contaminant levels not comparable to traditional fuels.60 

Comment: One commenter requested that the EPA clarify what 

it means by the upper end of the statistical range. Citing the 

EPA’s statement in the proposal that “it makes sense to base the 

traditional fuel comparison on the upper end of the statistical 

range,”61 the commenter asked for confirmation that the maximum 

values in the traditional fuel data set can be used for 

comparison with a NHSM since all data corresponding to the 

traditional fuel are valid for comparison, not just values that 

are below some arbitrarily determined statistical parameter. 

Response: The word ‘ranges’ in the proposed contaminant 

legitimacy criterion has been changed to ‘the full range’ in the 

final criterion issued today. This term more clearly indicates 

 

60 See 75 FR 31872.

61 See 76 FR 80481.
Page 195 of 319

the agency’s intent to include all true values in between the 

minimum and the maximum. 

The agency has also separated the concepts of ranges and 

traditional fuel survey data in the regulatory language in order 

to make the criterion more transparent. The pertinent regulatory 

text in today’s final rule reads as follows: “In comparing 

contaminants between traditional fuel(s) and a non-hazardous 

secondary material, persons can use data for traditional fuel 

contaminant levels compiled from national surveys, as well as 

contaminant level data from the specific traditional fuel being 

replaced. To account for natural variability in contaminant 

levels, persons can use the full range of traditional fuel 

contaminant levels, provided such comparisons also consider 

variability in non-hazardous secondary material contaminant 

levels.”

Comment: Several commenters noted that the agency proposed 

to allow the use of “national” surveys of traditional fuel data 

in the proposed contaminant legitimacy criterion and included 

several international data sources in its “Contaminant 

Concentrations in Traditional Fuels: Tables for Comparison” 

document.62 Several commenters asked that the word ‘national’ be 

removed from the contaminant legitimacy criterion. Other 

 

62 The EPA maintains a NHSM webpage with current information on contaminant 

levels in traditional fuels, examples of legitimacy determinations, and other 

information at http://www.epa.gov/epawaste/nonhaz/define/index.
Page 196 of 319

commenters asked that the EPA either remove the word ‘national’ 

or clarify that international data and surveys from other 

nations are also acceptable data sources. 

Response: The EPA has retained the proposed language, 

including the word “national,” which expressly allows national 

surveys of traditional fuel data to be used in contaminant 

comparisons for NHSMs used as a fuel in combustion units. A 

statement that national surveys can be used does not preclude 

the use of appropriate international data. In fact, as the 

commenters recognize, the EPA included several international 

sources in its analysis of traditional fuels. These 

international sources were limited, however, to situations where 

no data or minimal data could be found from national sources or 

the agency had no reason to believe that data from national 

sources would be significantly different. At issue is whether 

the data are representative of traditional fuels that are 

purchased and burned at operating boilers in the United States. 

The agency has decided that it is reasonable to assume that 

national surveys of traditional fuels contain information about 

fuels purchased and burned at operating boilers in the United 

States.

Comment: One commenter argued that the traditional fuel 

database compiled by the EPA should include the USGS coal data 
Page 197 of 319

from not only the United States but also from around the world 

because those fuels are currently in use. 

Response: The EPA has maintained its decision not to 

reference the USGS COALQUAL database in its traditional fuel 

contaminant tables. It is the agency’s understanding that the 

COALQUAL database contains trace metal analyses for coal and 

associated rocks taken directly from coal beds throughout the 

United States and that not all of these coal beds are currently 

being mined. It is also the agency’s understanding that as-mined 

coal typically undergoes a series of processing steps, including 

crushing, screening, washing and physical separation techniques 

to remove rock and other impurities prior to being blended into 

clean, graded and uniform coal products suitable for use in 

commercial boilers.63 

In comparison, the EPA contaminant tables referenced by 

commenters are based largely on a comprehensive dataset that 

contains approximately 32,000 records of pre-combustion 

contaminant analyses performed on coal, wood, biomass and fuel 

oil samples that were actually used as fuel at boilers across 

the country. Thus, the agency has decided that the EPA dataset 

is more representative of contaminant levels in coal actually 

burned at operating boilers than the COALQUAL database. As a 

 

63 Speight, J.G. Synthetic Fuels Handbook: Properties, Process, and 

Performance. McGraw-Hill, 2008. pg 141. 
Page 198 of 319

result, the EPA has decided not to use the COALQUAL database in 

developing the tables posted on the agency’s website. 

We would also note that the decision not to use USGS data 

is consistent with the agency’s position that product fuel oils, 

as opposed to virgin crude oil, should be measured for purposes 

of contaminant comparisons. As stated in the proposed rule, 

neither unrefined crude oil nor gasoline is typically burned in 

combustion units regulated by CAA sections 112 and 129. 

Similarly, as-mined coal is not typically burned in combustion 

units regulated by CAA sections 112 and 129.

Comment: One commenter suggested that for each contaminant 

or group of contaminants, either the UCL of the mean at a 90 

percent confidence level or the UPL at a 90 percent confidence 

level for NHSMs could be compared to the maximum value for the 

appropriate traditional fuel. 

Response: First, we would note that in the preamble to the 

recent proposed rule, the EPA indicated that when compared to 

the full range of contaminants in traditional fuels, suitable 

measures of NHSM contaminants would include the upper end of a 

statistical range, a calculation involving the mean and standard 

deviation or perhaps a single data point in situations where 
Page 199 of 319

data are limited. The agency also noted that the discussion in 

the preamble did not preclude “other reasonable methodologies.”64

With respect to the specific approaches suggested by the 

commenters, the EPA agrees with the approach of comparing the 

UPL at a 90 percent confidence level for each contaminant or 

group of contaminants in NHSMs to the maximum value for each 

contaminant or group of contaminants in the appropriate 

traditional fuel. Specifically, the UPL is an indicator of what 

a future measurement would be. In the context of NHSM 

contaminant levels, the UPL taken at a 90 percent confidence 

level would yield a number, and a combustor could be confident

that 90 percent of the time, the next measured contaminant level 

would be at or below that number. The UPL considers both the 

variability of the contaminant distribution and the uncertainty 

surrounding what the true mean is. The comment suggested taking 

a maximum value for traditional fuel contaminant levels and 

comparing it to the UPL at a 90 percent confidence level. 

Because both metrics account for the variability present in 

contaminant distributions, the EPA would consider this approach 

to be a reasonable methodology.

The EPA does not agree, however, with an approach of using 

the UCL of the mean. That is, the UCL of the mean, regardless of 

the confidence level, is a measure of the mean and does not 

 

64 See 76 FR 80481.
Page 200 of 319

adequately factor in the variability present in both NHSMs and 

traditional fuel contaminant levels. The metric would be 

appropriate for a mean to mean comparison, but that is not what 

the commenter suggested. The comment suggested taking a maximum 

(which takes full advantage of the variability present in 

traditional fuel contaminant levels) and comparing it to a mean 

(which ignores the variability present in NHSM contaminant 

levels). The EPA does not consider this approach to be a 

reasonable methodology.

To be clear, the EPA does not object to the use of 

confidence limits, or to the use of the UCL of the mean, on 

their own grounds. However, the agency believes it is 

inappropriate to make a comparison of mean contaminant levels in 

NHSMs to maximum contaminant levels in traditional fuels.

Comment: One commenter suggested that the EPA allow 

entities to compare contaminants between NHSMs and traditional 

fuels on a pound of contaminants per Btu (lb/MMBtu) basis, as 

the agency said it would consider in the preamble discussion to 

the 2011 NHSM Final Rule.65

Response: The EPA maintains its position that a direct 

comparison of contaminant levels, as opposed to the lb/MMBtu 

approach, is the most appropriate means of comparing contaminant 

levels. As was noted in the 2011 NHSM Final Rule, however, the 

 

65 See 76 FR 15525.
Page 201 of 319

agency may still consider the lb/MMBtu approach as guidance is 

developed for implementation. 

3. Categorical Non-Waste Determinations for Specific NHSM Used 

as Fuels

The new provisions at 40 CFR 241.4 were proposed to allow 

the EPA to list categorically certain NHSMs as non wastes --

when used as a fuel in a combustion unit. Based on these 

categorical non-waste determinations, facilities burning NHSMs 

that qualify for the provision will not need to demonstrate that 

the NHSM meets the legitimacy criteria on a site-by-site basis. 

The EPA has determined that these NHSMs are categorical nonwastes as described and are not discarded when used as a fuel in 

a combustion unit. 

Categorical non-waste determinations only apply, however, 

to NHSMs that are burned as a fuel in combustion units for the 

purpose of recovery energy. Burning a NHSM fuel in a combustion 

unit for energy recovery assumes a set of basic design 

requirements that ensures excess air pollutants are not formed 

and emission requirements under the CAA are met. As discussed in 

section III.D.2.c of this preamble, such basic design 

requirements include abilities to load the material into the 

unit, ensure the material is well mixed and maintain 

temperatures within unit specifications. For example, burning a 

whole tire in a boiler that is only designed to burn tires that 
Page 202 of 319

are chipped and/or dewired would not be considered a fuel burned 

in a combustion unit for the purpose of recovering energy. The 

agency is not including specific regulatory text regarding this 

point since we believe it is understood that to be burned for 

energy recovery, the combustion unit must be able to burn the 

NHSM as a fuel. 

a. Scrap Tires

In the December 23, 2011, NHSM proposed rule, the EPA 

proposed the following regulatory language under 40 CFR 241.4 

Non-Waste Determinations for Specific Non-Hazardous Secondary 

Materials When Used as a Fuel: “Scrap tires that are not 

discarded and are managed under the oversight of established 

tire collection programs, including tires removed from vehicles 

and off-specification tires.” Further, the addition of this 

provision (40 CFR 241.4(a)(1)) eliminated the need for the 

previous scrap tire provision at 40 CFR 241.3(b)(2)(i),66 which 

has been removed and reserved in today’s final rule. Today’s 

rule finalizes the proposed provision without changes.

 

66 The scrap tire provision in the 2011 NHSM final rule is now removed and the 

section reserved in today’s final rule: “(b) The following non-hazardous

secondary materials are not solid wastes when combusted:

(2) The following non-hazardous secondary materials that have not been 

discarded and meet the legitimacy criteria specified in paragraph (d)(1) of 

this section when used in a combustion unit (by the generator or outside the 

control of the generator):

(i) Scrap tires used in a combustion unit that are removed from vehicles and 

managed under the oversight of established tire collection programs.”
Page 203 of 319

Comment: One commenter stated, “In its latest proposal, EPA 

eliminates the need for scrap tires to meet its legitimacy 

criteria and simply declares that scrap tires collected under an 

established tire collection program are not waste regardless of 

whether they meet the agency’s legitimacy criteria.” 

Response: The EPA disagrees with this comment. The EPA has 

not eliminated the legitimacy criteria for scrap tires. The 

categorical determination for scrap tires (as with all the 

categorical determinations in this rule) simply applies the 

agency’s non-discard determination, made in the March 2011 rule 

and not reopened in this amendment, to the general category so 

that case-by-case determinations as to legitimacy would not need 

to be made by each facility. For the scrap tire category, scrap 

tires managed under established tire collection programs and 

used as a fuel need not make case-by-case legitimacy 

determinations. Moreover, the commenter has given us no 

information that the criteria are not met. In fact, the 

commenter simply repeats the argument made in previous 

rulemakings that the material is always a waste regardless of 

legitimacy criteria. 

Comment: Several commenters suggested that scrap tires 

should not have more restrictions under 40 CFR 241.4(a) for the 

categorical non-waste status than does resinated wood. The nonwaste determination for scrap tires, as proposed in 40 CFR 
Page 204 of 319

241.4(a)(1), read “Scrap tires that are not discarded and are 

managed under the oversight of established tire collection 

programs, including tires removed from vehicles and offspecification tires.” In comparison, the resinated wood 

description, as listed in 40 CFR 241.4(a)(2), is “Resinated 

wood.” The commenters reasoned that if all resinated wood can be 

non-waste, then all scrap tires should also qualify (regardless 

of the origin). 

Response: Please see the EPA’s response in the resinated 

wood section below (section III.D.3.b of this preamble) relating 

to the 241.4(a) criteria for resinated wood and the comparison 

to scrap tires. That response goes into detail explaining why 

the extra criteria are not needed for resinated wood and related 

discard issues. In addition, as noted previously in the NHSM 

rulemaking record (see docket EPA-HQ-RCRA-2008-0329), numerous 

tire piles have been created in the past whereas this is not the 

case for resinated wood used as fuel. The existence of these 

historic tire dumps demonstrates that some tires have not been 

treated as a valuable commodity therefore necessitating the 

additional discard qualification in regulatory text. The 

specific tires described in the categorical determination are 

handled as a valuable commodity and do not include discarded 

tires. 
Page 205 of 319

Comment: A commenter suggested that the EPA should add 

“off-specification tire components” to the regulatory language. 

This revision would be in addition to the proposed text at 40 

CFR 241.4(a)(1) that adds “off-specification tires.” 

Response: Off-specification tire components are covered in 

the 40 CFR 241.4 categorical non-waste determinations for scrap 

tires. The term ‘scrap tire’ is a general term for tires and can 

include, for example, whole tires, chipped tires, offspecification tires or off-specification tire components (i.e., 

tread, sidewall or base) that are removed from vehicles or are 

generated by tire manufacturers, including retailers or other 

parties involved in the distribution and sale of new tires. This 

formulation was also stated in the December 2011 NHSM proposal67

and is adopted for today’s final rule. The EPA sees no 

difference between tires and their various components. Thus, the 

EPA does not believe it necessary to modify the rule to include 

“off-specification tire components” in the codified definition. 

They are understood to be included in the categorical non-waste 

provision. 

Comment: Many commenters mentioned the difficulty in 

complying with the regulations since it is very difficult to 

distinguish between tires removed from vehicles (and offspecification tires) versus tires from other origins. In regard 

 

67 See 76 FR 80483.
Page 206 of 319

to this issue, one commenter stated, “a combustor cannot know 

the origin of the tire-derived fuel it is buying. In its 

response to requests for reconsideration of the CIWSI rule, the 

EPA responded to this issue by recognizing that it is not 

possible for a combustor to know the source of all NHSM fuel and 

declined to impose this requirement stating: 

"Rather, it is sufficient that the ultimate user verify 

that it is obtaining tires from an established tire 

collection program, which program can provide the user with 

reasonable assurance that it manages tires carefully from 

point of collection to point of burning and which does not 

receive tires which have been abandoned in landfills or 

otherwise. 76 Fed. Reg. 28318, 28322 (May 17, 2011)."

Therefore, the commenter requests that the EPA codify this 

statement in the NHSM rule and expressly allow combustors to 

rely upon certifications of fuel suppliers that the fuel sold is 

not a solid waste.

Another commenter said that for the EPA to require a tire 

storage facility to maintain separate classifications of tires 

(i.e., separating discarded tires from tire dumps from other 

tires) is not reasonable, because inspectors and operators would 

not be able to tell the piles apart. The EPA’s current 

definition of scrap tires would place undue financial hardship 

on contractors and storage facilities. 
Page 207 of 319

Response: The EPA has decided that a regulatory statement 

on this matter is not necessary since the actual requirement for 

the combustor to determine where its tires come from when they 

are coming from an established tire collection program (or a 

contractual agreement) is provided for under the CAA and 

interpretations provided for that regulation. For example, major 

source boilers have a recordkeeping requirement for a non-waste 

determination at 40 CFR 63.7555 “What records must I keep?” 

Within those regulations for major source boilers, it requires 

the combustor to demonstrate that NHSMs are a non-waste. To the 

extent that a combustor believes it appropriate, they may 

request haulers to verify that the tires would qualify as nonwaste under 40 CFR 241.4 when combusted. 

If there is question about the origin of the tires, the EPA 

inspectors will not assume that tires are from discarded 

sources. As we note in the Federal Register notice (76 FR 28318, 

28322), “It is EPA’s position that ultimate users are not 

responsible for knowing the source of all tires obtained from an 

established tire collection program... EPA does not interpret this 

language as requiring knowledge of each individual tire as this 

is a practical impossibility... users also should not assume that 

tires from established programs which participate in occasional 

cleanup days are discarded – both because there is no 

information that the tires from the cleanup efforts were 
Page 208 of 319

discarded (and these programs are designed to prevent 

discarding) and whether the kiln received tires from the 

sporadic cleanup days in any case.” 

The Federal Register notice that the commenter cited (76 FR 

28322) and a related letter to the docket (“Memorandum. 

Combustion in a Cement Kiln and Cement Kilns’ Use of Tires as 

Fuel.” April 25, 2011, Document ID: EPA-HQ-OAR-2002-0051-3582) 

provide sufficient guidance. The agency believes this issue does 

not merit additional regulation for the hauler.

b. Resinated Wood

In the December 23, 2011, proposed rule, the EPA proposed 

to designate in regulatory text that resinated wood is not a 

solid waste when used as a fuel. In making this determination, 

the agency analyzed these materials using the legitimacy 

criteria, concluding that resinated wood clearly is managed as a 

valuable commodity and has meaningful heating value and is used 

as fuel.68 While stating that these materials may not always meet 

the regulatory contaminant legitimacy criterion in every 

situation, we proposed to list categorically resinated wood as a 

non-waste fuel because, after balancing the regulatory 

legitimacy criteria and other relevant factors, the EPA 

determined that resinated wood that is used as fuel represents 

 

68 See 76 FR 80483.
Page 209 of 319

an integral component of the wood manufacturing process and, as 

such, is not being discarded when burned as fuel. 

Specifically, we noted the extent to which resinated wood 

is used as fuels throughout the wood manufacturing industry and 

that the use of resinated wood as fuel is essential to the wood 

manufacturing process. We also noted the prevalence of wood 

product plants that have been designed specifically to utilize 

these residuals for their fuel value; in fact many (if not most) 

wood products plants would not be able to operate as designed 

without the use of these materials. This determination was 

previously codified under 40 CFR 241.3 (b)(2)(ii) of the NHSM 

final rule, provided the resinated wood met the legitimacy 

criteria in 40 CFR 241.3(d)(1). However, based on the available 

information, as well as how this material is handled and used in 

the process, resinated wood is not being discarded when used as 

a fuel, and thus, should not be considered a solid waste when 

burned as a fuel. The EPA proposed to codify this determination 

by categorically listing resinated wood as a non-waste fuel in 

40 CFR 241.4(a)(2).69 By specifically listing it as a non-waste 

fuel, combustors of this material would not need to demonstrate 

that they meet the legitimacy criteria on a site-by-site basis.

The EPA finds that this reasoning is supported by the 

entire rulemaking record, as explained in the December 2011 

 

69 See 76 FR 80483-80484.
Page 210 of 319

proposal, which rationale is adopted for the final rule as 

further supported by responses to comments below. Thus, the 

agency has determined to list categorically resinated wood as a 

non-waste fuel. In addition, after considering comments received 

on the proposal, the agency is revising the definition of 

“resinated wood,” as codified in 40 CFR 241.2. 

Comment: Most comments on this issue were supportive of a 

categorical determination that resinated wood is a non-waste 

fuel. One commenter maintained that the record for this 

rulemaking clearly establishes that resinated wood is highly 

valued within the wood products industry for its high fuel 

value, stating that “Many facilities rely on mixing of these low 

moisture content wood materials with higher moisture content 

wood materials to manage and optimize combustion.” This same 

commenter also stated that “there exists within the wood 

products industry a developed market for purchase and sale of 

resinated wood between independent companies.” In fact, many 

wood-fired boilers at wood products plants that do not generate 

sander dust have been retrofitted with sander dust injection 

burners so that sander dust can be properly combusted in those 

units, taking full advantage of the heat energy of sander dust. 

Another commenter stated that “resinated fuels have been an 

integral part of the composite wood product industry’s 

production process since the industry was established decades 
Page 211 of 319

ago. As such, facilities’ combustion and energy systems were 

designed and constructed to utilize most if not all of their own 

wood and wood by-products, including resinated trim and sander 

dust. Excluding resinated wood fuels from our manufacturing 

processes would require significant re-engineering of our 

facilities and add insurmountable operating costs in order to 

substitute fossil fuels, as well as to transport and dispose of 

resinated wood fuels. Any other result would effectively make it 

nearly impossible for these manufacturing facilities to continue 

operations.” This same commenter also noted that “many of our 

facilities rely exclusively on resinated wood for its fuel and 

have limited access to substitutes.”

Another commenter provided two examples of mills that 

utilize nearly 100 percent of sander dust, either to create new 

product as part of the manufacturing process or as fuel. In 

addition, two state commenters supported the proposed 

categorical non-waste determination for resinated wood. 

Response: Nearly all of the comments received regarding the 

proposed categorical non-waste determination were supportive of 

categorically listing resinated wood as a non-waste fuel when 

burned in combustion units for energy recovery. As noted above, 

the agency did receive a few additional examples of how the use 

of resinated wood as a fuel is an integral part of the wood 

manufacturing industry’s production process (e.g., the 
Page 212 of 319

facilities that would have to be significantly re-engineered if 

they could not use resinated wood for its fuel value and the 

mills that use 100 percent of the sander dust it generates, 

either by recycling it back into the process or burning it for 

fuel). 

Although we received one comment critical of the EPA’s 

proposed listing of resinated wood as a non-waste fuel 

(addressed below), we did not receive any comments that argued 

or suggested that the use of resinated wood as a fuel is not an 

integral component of the wood manufacturing process. Thus, we 

agree with commenters who encouraged the EPA to finalize 

resinated wood as a categorical non-waste fuel and will finalize 

this determination in today’s rulemaking. 

Information in the record for this rulemaking clearly 

establishes that resinated wood is managed as a valuable 

commodity (40 CFR 241.3(d)(1)(i)) and has meaningful heating 

value and is used as a fuel in combustion units that recover 

energy (40 CFR 241.3(d)(1)(ii)).70 In addition, we generally have 

determined that most resinated wood meets the contaminant 

legitimacy criterion as well ((40 CFR 241.3(d)(1)(iii)), 

although we acknowledge that in some instances these materials 

 

70 See, e.g., 76 FR 80483. See also background document developed in support 

of the December 23, 2011, proposed rulemaking titled, “Resinated Wood, Scrap 

Tire, and Pulp/Paper Sludge Support Document” (EPA-HQ-RCRA-2008-0329-1880).
Page 213 of 319

may have levels of formaldehyde that are not comparable to 

traditional fuels.71 

The EPA confirms the position discussed in the proposal and 

adopts it as its final rationale that there are instances where 

it is appropriate for the EPA to balance the regulatory 

legitimacy criteria with other relevant factors in order to 

determine whether a material is a legitimate fuel or is merely 

being discarded by being combusted. We have determined that 

resinated wood is one such example. Although resinated wood may 

not meet the regulatory contaminant legitimacy criteria in every 

situation, it is clear that resinated wood is still a 

“legitimate” product fuel after one considers how integrally 

tied the use of resinated wood as a fuel is within the wood 

manufacturing process and industry. Nearly all comments received 

on this point concurred with this assessment. Thus, in today’s 

final rule, we are codifying the determination that resinated 

wood, based on all information and the totality of the 

circumstances, is a non-waste when used as a fuel. 

Comment: One commenter, however, stated that the EPA’s 

proposed categorical determination that resinated wood is a nonwaste fuel is unlawful and arbitrary. The commenter stated that 

the EPA is now proposing to simply “exempt” resinated wood 

altogether, regardless of who burns it and whether it meets the 

 

71 Id.
Page 214 of 319

legitimacy criteria. According to the comment, the EPA 

acknowledges that the formaldehyde levels in resinated wood 

would not always meet its contaminant legitimacy criterion –

i.e., would not be comparable to the levels in any fuel that 

companies would otherwise burn. The commenter states that the 

EPA also acknowledges that burning resinated wood increases the 

emissions of formaldehyde, but nonetheless finds that, “In 

general the motivation to use resinated wood as a fuel, even 

with the slightly higher formaldehyde levels, predominates over 

the motivation to dispose of the formaldehyde.” The EPA’s 

decision to remove the limits on the exemption for resinated 

wood and to “categorically” declare resinated wood to be a nonwaste – regardless of who burns it, regardless of how 

contaminated it is, and regardless of the reality that some 

companies may be burning resinated wood as a cheap means of 

disposing of their toxic formaldehyde wastes – underscores this 

point. 

The comment continues that the EPA nowhere claims that 

companies burning resinated wood that they have not generated 

pay for these materials. Indeed, the EPA does not deny that 

these companies are paid to take the resinated wood they burn. 

Thus, the EPA provides no reason to believe that the resinated 

wood that is burned by a company other than the one that 

generated it has not been discarded by the company that 
Page 215 of 319

generated it. Even under the EPA’s own view of the meaning of 

discard, resinated wood burned by companies other than the 

generator of the resinated wood would be waste but for the 

agency’s declaration that it is not waste. 

The commenter also states that the EPA admits that some 

companies may burn resinated wood because they want to dispose 

of the formaldehyde it contains (i.e., to dispose of the 

contaminated wood rather than to recover energy). Moreover, the 

levels of formaldehyde contamination in some resinated wood 

would exceed the EPA’s legitimacy criteria, but for the EPA’s 

declaration that these criteria do not apply. For these reasons 

as well, resinated wood is discarded even under the EPA’s own 

view of what that term means. 

Further, the comment states that sources’ alleged 

“motivation” for burning a material is to recover energy rather 

than to destroy the wood and the contaminants it contains –

assuming arguendo that a source’s motivation can even be 

determined – does not show that material is not a waste. Rather, 

resinated wood is a waste because it is discarded within the 

meaning of RCRA. Notably, the EPA does not suggest that there is 

any use for resinated wood that has been discarded other than –

assuming it is a “use” at all – burning it. Moreover, 

establishing a “motivation”-based test for whether resinated 

wood is or is not a waste conflicts with and defeats the CAA. 
Page 216 of 319

Thus, the agency’s categorical declaration that resinated wood 

is not a waste is unlawful. 

Response: The EPA strongly disagrees with the commenter’s 

characterization of its categorical determinations. In making 

categorical determinations, the agency is not “exempting” these 

materials from regulation as a solid waste (i.e., if not for 

this “exemption,” these materials would otherwise be regulated 

as solid waste). Rather, the EPA has determined that the 

specified NHSMs are not solid waste when used as fuels. Further, 

in making categorical determinations, the EPA is not saying that 

the legitimacy criteria are not relevant. In proposing the 

categorical non-waste determination for resinated wood, the 

agency stated we were “balancing the legitimacy criteria and 

other relevant factors based on the fact that resinated wood 

residuals that are used as fuels represents an integral 

component to the wood manufacturing process and, as such, 

resinated wood residuals are not being discarded when burned as 

fuels.”72 This remains the agency’s final finding in this rule.

Regarding the level of contaminants in resinated wood, the 

agency is not saying that resinated wood is a non-waste fuel 

“regardless of how contaminated it is,” as the commenter 

suggests. Based on all available information, the agency has 

concluded that resinated wood meets the legitimacy criteria for 

 

72 See 76 FR 80483.
Page 217 of 319

all contaminants with the possible exception in some situations 

of formaldehyde. In focusing specifically on formaldehyde, we 

also have stated that we have limited information regarding 

formaldehyde levels—that is, resins and adhesives containing 

formaldehyde react within the resin curing process leaving “free 

formaldehyde at levels less than 0.02 percent (or 200 ppm), but 

noted that levels will be reduced further due to new national 

rules being developed by the CARB Composite Wood ATCM, per new 

Public Law 111-199. Thus, we have not said that contaminants do 

not matter. Rather, we have carefully analyzed contaminant 

levels in resinated wood and have determined, based both on 

contaminant levels, as well as how the use of these materials 

represents an integral part of the wood product manufacturing 

process, that resinated wood materials are a legitimate nonwaste fuel. 

Further, we do not concede, as the commenter contends, that 

some companies burn resinated wood to destroy contaminants—in 

fact, we have determined just the opposite. We have determined 

that companies burning resinated wood do so because such an 

activity is integrally tied to their production process, not to 

dispose of the formaldehyde. This determination is based on that 

extent to which resinated wood is used as fuels throughout the 

wood manufacturing industry, as well as the fact that the use of 

resinated wood as fuel is essential to that industry (i.e., 
Page 218 of 319

plants have been designed to use these materials as fuels and 

would be unable to operate if resinated wood was not available 

as a fuel source).

Regarding the comments that the EPA acknowledges that 

burning resinated wood increases emissions of formaldehyde, the 

agency needs to correct this characterization. First, in the 

2011 NHSM final rule, we stated that the criterion or test in 

determining the contaminant legitimacy criterion is based on the 

level of contaminants in the secondary material itself and not 

by comparing the differences in emissions.73 However, responding 

to comments we received regarding emission levels associated 

with burning resinated wood as a fuel, the agency determined 

that the amount of formaldehyde that is emitted from burning 

resinated wood residuals is in fact likely to decrease, given 

that Public Law 111-199 will reduce formaldehyde levels in these 

materials.74

Regarding the commenter’s statement that companies that 

burn resinated wood that they have received from offsite do not 

pay for it, the EPA disagrees with the argument put forth by the 

commenter as the facts in this instance do not support such a 

premise. 

 

73 See, e.g., 76 FR 15502.

74 Id.
Page 219 of 319

As noted in the March 2011 final rule, inter-company 

transfers of resinated wood residuals are typically managed 

through buy-sell contracts and 6 percent of resinated wood 

residuals are sold into the fuel market and are used as either 

“furnish” (i.e., raw materials) or fuel at the receiving 

facilities.75 In addition, the EPA received additional comments 

on the proposed rule stating, “...there exists within the wood 

products industry a developed market for purchase and sale of 

resinated wood between independent companies.” 

Moreover, while contractual arrangements can be used as 

evidence that the material is managed as a valuable commodity 

and that discard is not occurring when a material is transferred 

beyond the control of the generator, the price of an NHSM is 

not, by itself, dispositive of whether the material is or is not 

a waste. The main indication that resinated wood residuals are 

not solid waste is the fact that they are used as fuels in a way 

that represents an integral component to the wood products 

industry. As the EPA noted in the March 2011 final rule, 

“resinated wood residuals transferred off-site are utilized in 

the same manner as self-generated resinated wood residuals 

(i.e., contained in the same bins as furnish materials used in 

the product, transferred via conveyors or ducts), which the 

 

75 See 76 FR 15500.
Page 220 of 319

plants are specifically designed to burn as a fuel, [and 

therefore] we agree that this does not constitute discard.”76

The comment that the agency has simply declared that 

resinated wood is a non-waste “regardless of who burns it” is a 

mischaracterization of this categorical non-waste determination. 

Based on all information provided to the agency, we have 

determined the use of resinated wood as a fuel is an integral 

part of the industry’s production processes and that these 

materials are managed as valuable commodities (i.e., fuels), 

have meaningful heating value and are used in combustion units 

that recover energy regardless of whether these materials remain 

within the control of the generator or are transferred offsite 

to another facility. On the other hand, we have no information 

that facilities are burning these materials merely to get rid of 

them (i.e., discard). 

The EPA finds irrelevant the commenter’s statement that the 

EPA is looking to a source’s motivation for using a material as 

a fuel conflicts with and defeats the CAA. The issue, rather, is 

whether motivation is relevant to a waste determination under 

RCRA. The D.C. Circuit confirmed the relevance of motivation in 

determining whether a recycled material is a waste. See, API v. 

EPA, 216 F.3d at 58 (court criticizes the EPA for not saying why 

it has concluded whether recycling motivation predominates over 

 

76 Id.
Page 221 of 319

a disposal motivation). In this case, it is clear that the 

motivation for burning the resinated wood is to utilize its 

inherent value as a fuel and not for disposal. Commenters have 

provided the agency with information that facilities generating 

and managing resinated wood residuals consider these materials 

to be an integral part of their production process—both in the 

value these materials provide as being a critical source of 

energy as well as being recycled back into the manufacturing 

process to create more wood products. Thus, we are not convinced 

that a facility that considers the use of resinated wood as a 

fuel to be an integral part of its production processes, as has 

been established in the record, is motivated to discard these 

materials by burning to get rid of them.

Comment: A few commenters stated that the EPA is not 

consistent in how discarded materials are designated as solid 

waste. In particular, the commenter stated that the EPA was 

proposing to list as a categorical non-waste fuel in 40 CFR part 

241.4 resinated wood regardless of whether it is previously 

discarded, while the agency would require processing for scrap 

tires that have been discarded in landfills.

Response: The agency disagrees that its treatment of 

resinated wood is inconsistent with its treatment of scrap 

tires. Nowhere does the agency state that resinated wood would 

be considered a non-waste fuel “regardless of whether it is 
Page 222 of 319

previously discarded.” The EPA, based on all information 

available, has determined that resinated wood is not being 

discarded when used as fuel, given the fact that resinated wood 

residuals that are used as fuels represent an integral component 

of the wood manufacturing process. If a shipment of resinated 

wood residuals was disposed of in a landfill, it would be a 

waste. In addition, if a shipment of resinated wood residuals 

were disposed of and later recovered to be used as a fuel, as is 

the case with scrap tires that are extracted from landfills, 

this would be a different scenario and would not be included 

within the categorical listing in 241.4(a)(2). 

As the record clearly shows, resinated wood is routinely 

handled and managed as a valuable fuel product within the wood 

products manufacturing industry. As noted in the rulemaking 

record (see docket EPA-HQ-RCRA-2008-0329), numerous scrap tire 

piles have been created in the past and it is a common practice 

to recover abandoned tires from tire piles and use them for 

fuel. This is not the case for resinated wood.

Comment: While supportive of the agency’s proposed listing 

of resinated wood as a non-waste fuel in 40 CFR part 241.4, two 

commenters suggested that the agency revise the definition of 

“resinated wood” as codified in 241.2. Currently, “resinated 

wood” is defined as, “wood products (containing resin adhesives) 

derived from primary and secondary wood products manufacturing 
Page 223 of 319

and comprised of such items as board trim, sander dust, and 

panel trim.” However, these commenters request the EPA to revise 

this definition in order to clarify that the “spectrum of 

resinated materials currently used as fuels throughout the wood 

product manufacturing process are included in the definition.” 

Thus, commenters urge the EPA to revise the definition of 

resinated wood as follows: “Resinated wood means wood products 

(containing binders and adhesives) produced by primary and 

secondary wood products manufacturing. Resinated wood includes 

residues from the manufacture and use of resinated wood, 

including materials such as board trim, sander dust, panel trim, 

and off-specification resinated wood products.”

The suggested revised definition proposes two changes. 

First, the suggested definition replaces the phrase “containing 

resin adhesives” with the phrase, “containing binders and 

adhesives.” The second suggested revision to the definition is 

the specific inclusion of “off-specification resinated wood 

products.” Commenters have indicated that these materials 

include materials that do not meet manufacturing specifications 

or are otherwise physically marred or damaged and thus, are not 

sold in the marketplace. This class of materials would not be 

expected to be chemically different than the resinated wood 

products that meet the manufacturing “on-spec” requirements. For 

example, off-specification resinated wood products would not be 
Page 224 of 319

expected to have higher amount of resins (and therefore 

contaminants) than their on-specification counterparts. 

Commenters have indicated that off-specification resinated wood 

products are identical to their on-specification counterparts 

chemically and only differ in that they are do not meet a 

manufacturing quality or standard.

Response: The agency recognizes that in order for a 

categorical non-waste determination to be meaningful and 

effective, it must be clear about the universe of materials that 

such a categorical non-waste determination encompasses. Thus, we 

agree with commenters who suggested specific revisions to the 

definition of “resinated wood” contained in part 241.2. 

Specifically, the EPA agrees that these revisions create a 

definition that more accurately captures the scope of resinated 

wood and is more representative of the resinated materials 

currently used as fuels throughout the wood product 

manufacturing process. First, by including the terms “binders” 

and “adhesives,” the universe of materials that we consider to 

be within this definition should be more clear, as these terms 

are widely used and accepted within the wood products 

manufacturing industry.

With respect to the inclusion of off-specification 

resinated wood products, the EPA finds it appropriate to include 

this class within the definition of resinated wood. We note, 
Page 225 of 319

however, that to the extent that a facility has reason to expect 

that the off-specification wood products are off-spec for 

chemical reasons, such that the levels of contaminants are 

expected to be greater than their on-spec counterparts, the EPA 

would not consider such materials to be within the scope of this 

definition. The agency will make this point more clear by 

specifying in the definition that the term “off-specification 

resinated wood products” are off-spec due to the fact that they 

do not meet a manufacturing quality or standard. Thus, in 

today’s final rule, we are codifying the definition of resinated 

wood as follows: “Resinated wood means wood products (containing 

binders and adhesives) produced by primary and secondary wood 

products manufacturing. Resinated wood includes residues from 

the manufacture and use of resinated wood, including materials 

such as board trim, sander dust, panel trim and offspecification resinated wood products that do not meet a 

manufacturing quality or standard” (emphasis added).

Comment: One commenter noted that there are additional 

secondary materials produced by the wood manufacturing industry 

that are similar to resinated wood and, thus, should also be 

considered a non-waste fuel. The production of flooring and 

furniture creates final finishing trim, sander dust and process 

breakage that are both solid and resinated wood materials. In 

some cases, these materials are coated with finish materials 
Page 226 of 319

used to color and protect the finished product. The commenter (a 

utility) indicated that their facilities receive these materials 

from furniture and flooring manufacturers and utilize them to 

offset the fuel load from fossil fuels due to their high heat 

capacity. Thus, the commenter requests that the EPA expand its 

definition of resinated wood materials to include these 

additional wood manufacturing secondary materials as non-waste 

fuels or otherwise describe the circumstances under which these 

additional materials would be considered a non-waste fuel. 

Response: It is possible that these materials (or some of 

these materials) could be within the definition of “resinated 

wood,” as codified in 40 CFR part 241.2; however, commenters 

have not provided the agency with information regarding the 

factors involved in determining whether these additional types 

of coated materials are legitimately used as product fuels. That 

is, commenters have not provided information regarding whether 

these “finishing materials” could have contaminant concerns and 

whether they are routinely used as fuels. Subsequent to this 

rulemaking, the agency would welcome information regarding these 

materials in order to make an informed decision regarding 

whether these materials fit within the definition of “resinated 

wood.” Alternatively, the commenter may petition the agency to 

receive a non-waste determination per the petition process 

established in 40 CFR 241.3(c) if the commenter believes that 
Page 227 of 319

this material may not be within the definition of “resinated 

wood.” 

4. Rulemaking Petition Process for Other Categorical Non-Waste 

Determinations (40 CFR 241.4(b))

The EPA recognizes that there may be other NHSMs that can 

also be considered non-wastes when used as fuels in combustion 

units when balancing the legitimacy criteria and other relevant 

factors. Thus, under today’s rule, we are finalizing the process 

outlined in the proposed rule whereby persons can submit a 

rulemaking petition to the Administrator where they can identify 

and request that additional NHSMs be listed in section 241.4. 

The petition process is similar to 40 CFR 260.20, where any 

person may petition the Administrator to modify or revoke any 

provisions of the hazardous waste rules and where procedures 

governing the EPA’s action on those petitions are established. 

The 40 CFR 260.20 standards reflect normal, informal rulemaking 

procedures under the APA and thus, serve as an appropriate model 

for the NHSM rulemaking petitions under this section. 

In the context of a rulemaking petition under section 

241.4(b), any person can petition the Administrator for a 

regulatory amendment to identify and request that additional 

NHSMs be included on the list of materials in section 241.4(a) 

that are not solid wastes when used as a fuel in a combustion 

unit. To be successful, the petitioner needs to demonstrate to 
Page 228 of 319

the satisfaction of the Administrator that the proposed 

regulatory amendment involves a NHSM that has not been 

previously discarded (i.e., was not initially abandoned or 

thrown away), or if discarded, has been sufficiently processed 

into a legitimate fuel. The petitioner must also demonstrate 

that the material is used as a non-waste fuel in a combustion 

unit because it either meets the legitimacy criteria, or, after 

balancing the legitimacy criteria with other relevant factors, 

such NHSM(s) is not a solid waste when used as a fuel in a 

combustion unit. 

If the applicant believes that the NHSM is a legitimate 

product and not discarded despite not meeting the legitimacy 

criteria, additional information must be submitted to explain or 

describe why such NHSM should be considered a non-waste fuel. 

Possible factors to address include, but are not limited to:

The extent that use of the NHSM has been integrally tied to 

the industrial production process. Information can include 

combustor design specifications, the extent that use of the 

material is integrated across the industry and the extent 

that use of the NHSM is essential to the industrial 

process, 

The extent that the NHSM is functionally the same as the 

comparable traditional fuel, and

Other relevant factors.

The application is required to include: (1) the 

petitioner’s name and address; (2) a statement of the 

petitioner’s interest in the proposed action; (3) a description 
Page 229 of 319

of the proposed action, including the specific NHSM, the 

industry (i.e., NAICS code) and functional use (i.e., industrial 

functional code listed in 40 CFR 710.52(c)(4)(i)(C)); and (4) a 

statement of the need and justification for the proposed action, 

including any supporting tests, studies or other information. 

Where such NHSM(s) do not meet the legitimacy criteria, the 

applicant must explain why such NHSM(s) should be considered a 

non-waste fuel, balancing the legitimacy criteria with other 

relevant factors. 

Under this petition process, the Administrator makes a 

tentative decision to grant or deny a petition and then publish 

notice of such tentative decision, either in the form of an 

ANPRM, a proposed rule or a tentative determination to deny the 

petition, in the Federal Register for written public comment. 

The Administrator could, at its discretion, hold an informal 

public hearing to consider oral comments on the tentative 

decision. After evaluating all public comments, the 

Administrator makes a final decision by publishing in the 

Federal Register a regulatory amendment or a denial of the 

petition.

Comment: One commenter does not support use of the 

legitimacy criteria, as provided in the proposed section 

241.4(b)(3) to make a determination. A material which has not 

been discarded is, by definition, not a solid waste. However, if 
Page 230 of 319

the EPA believes that other factors still should be considered, 

then the only other factor which should be considered is whether 

the material is being used legitimately as a fuel. The remaining 

legitimacy criteria are (and should be) irrelevant.

Response: As discussed in the 2011 NHSM final rule, 

“legitimacy” is shorthand for referring to NHSM that are not 

abandoned or thrown away, are saved and are reused by being 

burned for their value as a fuel.77 The legitimacy criteria are 

the factors needed to be examined to make this determination. 

For example, it is relevant how the NHSM is managed and its 

heating value since burning materials that have minimal or 

limited heating value shows the material is being burned for 

discard and not energy recovery. In addition, the extent to 

which contaminants are present in NHSMs may also indicate that 

the real reason for burning the secondary material is simply to 

destroy or discard them—referred to as ‘‘sham’’ recycling. Thus, 

the agency is not simply ‘‘punting’’ to its legitimacy criteria 

but believes they provide a valid basis for showing that a NHSM 

is more commodity-like than waste-like.

Comment: The current petition process is limited to NHSMs 

when used as fuels. Absent from this petition process are NHSMs 

used as ingredients and previously discarded materials that meet 

the fuel legitimacy criteria. We do not understand this 

 

77 See 76 FR 15471.
Page 231 of 319

distinction and urge the EPA to expand both the current and 

proposed petition processes to allow for non-waste 

determinations for a wider range of NHSMs.

Response: In general, the 40 CFR part 241 regulations 

establishes a self-implementing approach for NHSM that can 

consider site-specific information, if necessary (i.e.,

facilities will make a self-determination of whether the nonhazardous secondary fuel or ingredient in question meets the 

regulatory criteria). We note it is the EPA’s intention to 

indicate in these rules, as clearly as possible, which nonhazardous materials used as fuels or ingredients in combustion 

units are or are not considered solid waste based on the 

criteria laid out in regulatory text. The agency expects this 

self-implementing approach will govern the majority of 

situations, including NHSMs used as ingredients and NHSMs 

processed from previously discarded materials. 

We would also note that the regulated community prior to 

proposing the December 2011 proposed rule and commenters to that 

proposed rule did not provide any instances where ingredients 

are combusted or are processed from previously discarded 

material that would be a candidate for listing categorically. 

Therefore, we do not believe it necessary to modify the proposed 

rule to address this situation. However, to the extent that 

there are instances where such materials do exist, persons can 
Page 232 of 319

always petition the EPA to modify the rules, including allowing 

ingredients that are combusted to be categorically listed to 

account for such materials. 

Comment: In the NHSM Proposal, the EPA recognizes that a 

material can have levels of contaminants higher than traditional 

fuels, but still be combusted for a legitimate, energy-producing 

purpose (see 76 FR 80483 discussing resinated wood). The EPA 

also has proposed that this is true for hazardous secondary 

materials as well (see 76 FR 44094, 44122; July 22, 2011). 

Notwithstanding this admission, the EPA is not proposing to 

amend its legitimacy criterion for contaminants to make it a 

consideration, rather than a mandatory criterion. Thus, the 

EPA's NHSM Proposal is internally inconsistent. Under 40 CFR 

241.3(d)(iii), any material that has contaminants in 

concentrations higher than those found in traditional fuels is 

automatically considered a waste, no matter how integral the use 

of the material is to the manufacturing process or how 

legitimate the combustion is to the purpose of energy recovery. 

In contrast, under proposed 40 CFR 241.4, EPA recognizes that 

materials can have high levels of contaminants and still be nonwaste material being legitimately combusted for energy recovery. 

To justify this inconsistency, the EPA argues that it needs to 

make a case-by-case determination that a material with higher 
Page 233 of 319

levels of contaminants is a non-waste to “prevent sham 

recycling” (see 76 FR 80482).

Response: The EPA disagrees with the comment that the mandatory 

nature of the self-implementing § 241.3 standards (including the 

contaminant legitimacy criterion) for individual facilities is 

inconsistent with the non-waste determinations outlined in § 

241.4. In particular, the legitimacy criteria (including the 

contaminant legitimacy criterion) must be met under the selfimplementing standards for individual facilities outlined in § 

241.3, but the same criteria may be balanced by the EPA with 

other relevant factors under the categorical non-waste 

determinations outlined in § 241.4. 

These differences are necessary and appropriate. Where a 

particular NHSM may not meet all the legitimacy criteria 

outlined in §241.3(d)(1), but the material is being used as a 

legitimate fuel, the agency has decided it is necessary to 

require a formal determination (i.e., not a self-implementing 

decision) to prevent materials from being burned for discard 

under the guise of recycling. Furthermore, the agency has 

decided that such a determination should be subject to public 

notice and comment. In cases where the difference between 

recycling and waste treatment is difficult to distinguish, as is 

the case when elevated levels of contaminants are present, the 

potential for abuse is likely, and thus, regulatory oversight is 
Page 234 of 319

appropriate when making a waste/non-waste determination. This 

approach is also consistent with what the EPA proposed for the 

hazardous secondary material rule cited by the comment—that is, 

the balancing test would be used by the EPA in a petition 

process, not as a self-implementing determination. 

Comment: One commenter requested that the EPA should 

specifically recognize in the categorical petition that the 

existence of a supply contract between a generator of NSHMs and 

a combustor, with specifications that the NHSM must meet, should 

be considered dispositive evidence that the NHSM is not a waste 

and is combusted for energy recovery, not disposal.

Response: We disagree with the commenter that the mere 

existence of a contract between the generator and combustor is 

dispositive evidence of the material being a non-waste. However, 

existence of a contract is a factor to be considered in a 

categorical non-waste determination. For example, under 40 CFR 

241.4(a)(1), scrap tires managed under established tire 

collection programs are a categorical non-waste and the 

definition of “established tire collection program” (40 CFR 

241.2) explicitly recognizes contracts as evidence that the 

material has not been discarded. Specifically, “Established tire 

collection program” means “a comprehensive collection system or 

contractual arrangement [emphasis added] that ensures scrap 
Page 235 of 319

tires are not discarded and are handled as a valuable commodity 

through arrival at the combustion facility...” 

Comment: The timeframe for which the EPA must grant or deny 

the request should be included as well as defining the length of 

time of 30 days that these notices will be open to public 

comment. What is the legal implication of an “informal public 

hearing?” How does this differ from a public information 

meeting? If it is “informal,” what is the purpose? What 

administrative procedures apply to comments made during the 

“informal public hearing?”

Response: The agency is not imposing a deadline on its 

decision to grant or deny a petition, or a specific time period 

for public comment, due to the potentially wide range of issues 

involved in considering a categorical non-waste petition and 

because of the many factors beyond its control. Informal public 

hearings, similar to formal public hearings, provide an 

opportunity for the public to provide comments and oral 

testimony on proposed agency actions . All testimony received 

becomes part of the public record. Public meetings, on the other 

hand, are less formal; anyone can attend, there are no formal 

time limits on statement, and the agency and/or the facility 

usually answer questions. The purpose of the meeting is to share 

information and discuss issues, not to make decisions. 
Page 236 of 319

Comment: The final rule should make clear that the denial 

of a petition would not bar the filer of the denied petition 

from filing a subsequent petition for the same location and same 

materials.

Response: Where the information submitted to make a 

categorical non-waste determination has fundamentally changed, 

the EPA agrees that a petition to categorically list a NHSM can 

be resubmitted for review.

5. Materials for Which Additional Information was Requested 

a. Pulp and Paper Sludge

In the March 2011 NHSM final rule, the EPA concluded that 

pulp and paper sludges meet the legitimacy criteria and, thus, 

can be burned as a non-waste fuel provided such combustion units 

are within the control of the generator in accordance with 

section 241.3(b)(1).78 The December 2011 proposed rule discussed 

the information we currently have on pulp and paper sludges, and 

the additional information that the agency would need in order 

to categorically list these materials in 40 CFR 241.4(a) as a 

non-waste fuel.79 If such information were provided to the EPA, 

the agency would then consider the legitimacy criteria and other 

 

78 Pulp and paper sludges almost entirely remain on-site and within the 

control of the generator when burned as fuels. To the extent that pulp and 

paper sludges do not remain within the control of the generator and are used 

as fuels, the petition process established in 40 CFR 241.3(c) could apply to 

these materials, as appropriate.

79 Additional information needed to categorically list pulp and paper sludges 

is discussed at 76 FR 80485. 
Page 237 of 319

factors relevant to a determination that these sludges are not

solid wastes when combusted. 

This categorical listing would put pulp and paper sludges 

in the same general grouping as resinated wood residuals. For 

resinated wood residuals, the EPA considered that use of that 

material as a fuel has been integrally tied to the industrial 

production process and is consistent with that of a fuel 

product. The proposal discussed similar information that was 

needed by the agency to support adding pulp and paper sludges to 

40 CFR 241.4(a) as a categorical non-waste. 

Based on the comments received and information submitted, 

the EPA is listing as a categorical non-waste fuel under section 

241.4 those dewatered pulp and paper sludges that are not 

discarded and are generated and burned on-site by pulp and paper 

mills that burn a significant portion of those residuals. Such 

residual must be dewatered and managed in a manner to preserve 

the meaningful heating value of those materials.

This determination for pulp and paper sludge as a 

categorical non-waste represents the agency’s finding that, 

after balancing the regulatory80 legitimacy criteria with other 

 

80 As the EPA has previously stated (76 FR 15460), the Agency has established 

regulatory legitimacy criteria which may be used by companies on a case-bycase basis to show that they are not discarding material when used in a 

combustor. However, for the categorical determination, the Agency has 

determined that it is appropriate for the Agency, itself, to make the discard 

determination for material that does not meet the more strict regulatory 

criteria. Thus, the EPA has developed the categorical determination. 
Page 238 of 319

relevant factors, the burning of this material as described in 

the categorical listing is a commodity fuel for legitimate 

energy recovery and not discard. That is, the agency has 

concluded that, for pulp and paper mills that burn a significant 

portion, pulp and paper sludges are integral to the mills’ 

operations and provide a critical source of energy. Such mills 

are not burning these dewatered pulp and paper sludges to 

discard them but are burning them as a legitimate commodity 

fuel. These facilities take the steps necessary to dewater the 

pulp and paper sludges and to manage the dewatered sludge to 

maintain its meaningful heating value and not to dispose of the 

sludge. In addition, the agency finds for facilities burning a 

significant portion of the dewatered sludge that:

(1) The sludges are managed in a manner that preserves 

meaningful heating value and, therefore, meets the managed as a 

valuable commodity (241.3(d)(1)(i)).

(2) Dewatered sludge (i.e., dewatered through appropriate 

water removal practices, including dewatering presses, rotary 

driers, etc.) meets the meaningful heating value and used in 

combustion units that recovery energy criterion 

(241.3(d)(1)(ii)).

(3) The sludge meets the comparable contaminant criterion 

(241.3(d)(1)(iii)). 
Page 239 of 319

The fact that these sludges meet the contaminant legitimacy 

criterion, in the EPA’s view, show that these sludges when 

burned on-site are not being discarded. While the agency is not 

defining a specific percentage of dewatered pulp and paper 

sludges that would need to be burned to qualify for the 

categorical listing in section 241.4, the agency would consider 

that the 42 mills that responded to an AFPA survey81 and that use 

dewatered pulp and paper sludge as fuels at a significant rate 

(between 70-100 percent of these materials that are generated 

and burned) meet the listing description. We also find that 

other mills that burn a significant portion of their dewatered 

pulp and paper sludges on-site as fuel would qualify for the 

listing description.82 For the pulp and paper mills that burn a 

relatively small percentage of their dewatered pulp and paper 

sludges on-site as a fuel (e.g., the five mills that responded 

to the AFPA survey that burn less than 20 percent), the agency 

has determined that those sludges are not viewed the same by the 

mill operator in that they do not need to rely on them for their 

 

81 See April 2, 2012, letter from Timothy G. Hunt to James Berlow. A copy of 

this letter has been placed in the docket for today’s rulemaking.

82 While the Agency is not including a specific requirement for pulp and paper 

mills to document the amount of dewatered wastewater treatment residuals they 

burn on-site as a fuel, we would recommend that such pulp and paper mills 

include such documentation in case there are any questions as to whether the 

pulp and paper mills dewatered wastewater treatment residuals qualifies for 

the categorical listing in 241.4. As an alternative, the pulp and paper mill 

can request the Agency to confirm (via letter) that the facility generates 

and burns on-site a significant portion of pulp and paper sludges such that

the facilities pulp and paper sludges are included within the categorical 

listing.
Page 240 of 319

energy value and are not included in the non-waste categorical 

listing in section 241.4.

However, there is likely little difference as to how pulp 

and paper sludge may be defined under NHSM rules, whether a 

categorical or a facility-specific non-waste determination. That 

is, such dewatered pulp and paper sludges may still be 

considered non-waste fuels when burned as a fuel for energy 

recovery at mills that burn a relatively small percentage of 

these materials, although the rules require those facilities to 

document on a facility-specific basis that such sludges are nonwaste fuels. As discussed in the final NHSM rule (76 FR 15488), 

dewatered pulp and paper sludges that are burned within the 

control of the generator and meet the legitimacy criteria, 

likely are non-waste fuels and thus can be burned in units 

subject to CAA section 112 requirements. 

The agency has restricted the categorical listing to those 

dewatered pulp and paper sludges that are burned on-site because 

the agency has minimal information on how these NHSMs are 

managed when shipped offsite.83

Outlined below are commenters’ responses to the agency 

information requests regarding pulp and paper sludges and a 

categorical non-waste determination. 

 

83 We note that in the situation where pulp and paper sludges are transferred 

beyond the control of the generator, a facility can petition the Agency to 

receive a non-waste determination, as appropriate. 
Page 241 of 319

Comment: The EPA requested information on how pulp and 

paper mill sludge is used as a legitimate fuel and not discarded 

at pulp and paper mills and how the material is integrated into 

the industrial production process. 

In responding to the agency’s request, commenters first 

provided a summary of energy needs by the pulp and paper 

industry. The commenters indicated that the industry is somewhat 

unique in its energy profile and in how individual mills select 

appropriate fuels to support their energy needs. Most pulp and 

paper mill boilers are specifically designed to handle a variety 

of fuels; few boilers are designed to burn just 

traditional fuel. Even mills with boilers specifically permitted 

as pulp and paper sludge boilers also burn other fuels. Over the 

years, the industry has recognized the benefits of burning 

secondary materials, particularly those generated on-site. These 

secondary materials are derived from and have characteristics 

similar to traditional fuel, particularly the biomass used to 

produce pulp and paper products.

Mills do not usually burn just one type of fuel at any one 

time. Some mills rely heavily on coal, others on natural gas or 

biomass. According to the commenter, the choice of fuel depends 

on availability, cost and need. Hogged fuel or coal may be the 

underlying fuel but it is supplemented by other traditional and 

non-traditional fuels. This is done in order to meet the energy
Page 242 of 319

needs of the mill but also to address best management practices 

for the boiler and meet air quality requirements. If the hogged 

fuel is wet, coal or resinated wood may be added to boost heat 

value. If the boiler is burning too hot, the addition of pulp 

and paper sludge enables the mill to regulate temperature. Pulp 

and paper sludge also may be burned because it has the best fuel 

value for the price. All of these decisions are based on the 

boiler conditions, fuel availability, energy needs, air quality 

requirements, as well as costs, and all are considered when the 

energy manager determines the right mix of fuel in any given 

day.

As a result, the quantities of different types of fuels 

burned over the course of a year differ and the mill may not 

burn 100 percent of the available fuel generated during that 

year. Not all pulp and paper sludges are burned at a given mill 

over the course of a year nor are all recycled process residuals 

(old corrugated cardboard rejects) or all hogged fuel. The 

commenter emphasized that if only a percentage of a secondary 

material generated by the industry is used as a fuel, that it 

does not negate its value as a fuel. Rather, it reflects the 

realities of running a boiler for which the economic and 

operating conditions are interconnected and dynamic.

For example in one mill, the commenter indicated that 

combination boilers are designed to burn a wide variety of fuels 
Page 243 of 319

efficiently and cleanly. Two mills’ boilers currently burn tirederived fuel,84 while one burns waste paper generated at the 

mill. They all are capable of burning one or more fossil fuels: 

oil (including used oil), coal and gas. The four combination 

boilers burn large amounts of biomass, either generated on-site 

or purchased commercially. A portion of three of the mills’ 

biomass consists of sludge generated on-site from their 

wastewater treatment processes.

One state commenter also indicated that most mills operate 

boilers that are specifically designed to handle a variety of 

fuels -- few boilers are designed to burn just traditional fuel 

and mills do not usually burn just one type of fuel at any one 

time. Bark and biomass fuel may be the primary fuel but it is 

supplemented by other traditional or alternative fuels. 

Secondary materials have been an important alternative fuel 

used safely by the mills in the commenter’s state for many 

years. Most of that state’s mills' have multi-fuel boilers. 

Their fuel handling equipment, mill wastewater treatment systems 

and other ancillary equipment were designed to combust 

alternative fuels, including pulp and paper sludge. Use of these 

fuels reduces reliance on purchased biomass and/or fossil fuels 

and provides a vehicle for beneficial reuse of the materials. In 

 

84Tire-derived fuel used in the paper industry must be dewired since the wires 

often clog the feed system. Thus, the industry does not utilize whole tires. 
Page 244 of 319

light of the greater stringency of the CISWI regulations, the 

state indicated that the mills are likely to landfill 

these materials instead of recovering their fuel value if these 

materials are considered solid waste under the CISWI standards.

Another industry commenter stated that four of their five 

U.S. pulp mills produce wastewater treatment residuals that are 

burned in biomass-fired combination fuel boilers. At one mill, 

the residual solids are harvested and sold under a purchase 

agreement to an Electric Utility Generating plant burning 

various sources of biomass because that mill does not have a 

biomass boiler designed to burn the residuals. The residuals are 

primary clarifier solids (mostly wood fibers too short for 

product use) which are harvested by dewatering through a screw 

press. The residuals are stockpiled in a specific managed area 

before being trucked to the power company. At that site, the 

materials are processed and conveyed with other forms of biomass 

for fuel in their biomass boiler. Use of the wastewater 

treatment residuals from the mill as a fuel at the purchasing

site is permitted in their air permit. 

One commenter indicates that the energy manager at a mill 

will determine the approximate amount of different types of 

fuels needed to obtain the most energy under the best operating 

conditions. As pulp and paper sludge is generated, it is 

directed toward the hogged fuel pile or towards other non-fuel 
Page 245 of 319

uses. This decision is based on whether the mill’s boiler 

is designed and permitted to burn pulp and paper sludge and the 

amount is determined by the energy demands on that particular 

day.

Another commenter believes that the fact that not all pulp 

and paper sludge is combusted at pulp and paper mills is 

evidence that the wood products industry only combusts pulp and 

paper sludge for legitimate energy recovery and not for

disposal. According to the commenter, when the pulp and paper 

sludge is not needed as a fuel, it is used for non-fuel purposes 

or is discarded. When it is combusted, it is combusted for its 

energy value as a legitimate fuel.

One mill described by a commenter has elected to divert its 

own-make bark to beneficial use as mulch, rather than burning 

it, because it is of poorer quality than commercially available 

biomass. That same mill has recently invested in a new belt 

press which provides high quality sludge as fuel for its 

combination boiler. Since the press was installed in 2011, the 

percentage of mill sludge burned has increased to 80 percent 

from under 50 percent. Currently, the mill is burning more of 

the sludge from its process than the bark it also generates.

At another plant, the commenter indicates that sludge is a 

by-product of the AST process. Their mills employ primary 

clarifiers to separate out solids from wastewater, of which 50 
Page 246 of 319

percent is wood fiber, the primary component.85 These solids are 

staged in holding or blend tanks prior to drying. In addition to 

primary clarifiers and aeration basins, AST systems employ 

secondary clarifiers (large, open, circular concrete tanks) in 

which biological solids exiting the aeration basin(s) are 

separated by gravity from wastewater. The process is carefully 

regulated to accomplish two objectives: making the water as 

clean and free of solids as possible while retaining activated 

sludge (active microbes) to re-inject into the biological 

treatment stage of the process. As part of this continuous loop, 

some activated sludge must be removed from the system to 

maintain the optimal population of active microbes for effective 

treatment.

After excess secondary sludge is removed from the treatment 

loop at three of the mills, it is mixed with primary sludge in 

blend tanks prior to being dried on belt presses to a suitable 

moisture level for burning or other uses. Sludge is introduced 

into the mills’ solid fuel feed systems by means of conveyers 

where it becomes thoroughly mixed with other fuels in the 

conveyer systems before being introduced into the mills’ 

combination boilers. At one mill, primary sludge is dried 

separately by means of screw presses while secondary sludge is 

 

85 Washington State Department of Ecology Industrial Footprint Project Waste 

Stream Reduction and Re‐Use in the Pulp and Paper Sector, June 2008.
Page 247 of 319

dried using a belt press. The two fuels are fed separately by 

conveyers onto the mill’s main solid fuel conveyer which 

transports the bark/sludge mixture to a surge bin. The fuel is 

passed through a “waste heat dryer,” where it is briefly exposed 

to boiler flue gas before being fed into the combination boiler. 

The process at all four mills is continuous. Operators monitor 

and manage the sludge on a 24 hour basis. Sludge drying takes 

place entirely within buildings where the tanks, pipes, mixers, 

pumps, polymer feed systems, conveyers, presses, diversion gates 

and valves, monitoring devices and other equipment necessary to 

produce suitable sludge are housed.

Sludge burned in the boilers is transported to the boilers 

on feed systems designed to ensure sludge, biomass and other 

solid fuels are homogeneous, thoroughly mixed and not exposed to 

the elements while being conveyed to the boilers. After its 

removal from wastewater treatment, no sludge touches the ground 

until it is burned, beneficially used (e.g., recycled feedstock 

to make newsprint) or landfilled.

The commenters indicate that the moisture content of 

biomass is highly variable. Operators control fuel use based on 

the mill’s need for steam and electricity, fuel costs, fuel 

quality and fuel availability. All factors can change at a

moment’s notice since the production process is constantly 

changing. Pulp and paper production swings or curtailments are 
Page 248 of 319

common. Energy demand, fuel cost or fuel quality may make it 

necessary or desirable to reduce biomass and sludge combustion, 

even to switch entirely to fossil fuels. Environmental emissions 

occasionally can be a factor in fuel use, particularly during 

boiler startup or shutdown, or when the mill is experiencing 

rapid fluctuations in steam demand. 

Response: Based on the information submitted, and as 

discussed further in our responses below, the EPA is listing as 

a categorical non-waste fuel under section 241.4 dewatered pulp 

and paper sludges that are not discarded and are generated and 

burned on-site by pulp and paper mills that burn a significant 

portion of such materials where such dewatered residuals are 

managed in a manner that preserves the meaningful heating value 

of the materials.

This determination for pulp and paper sludge as a 

categorical non-waste fuel represents the agency’s finding, 

after balancing the legitimacy criteria with other relevant 

factors, that those mills that burn a significant portion of 

these pulp and paper sludges are burning them as a commodity 

fuel for energy recovery and not discard. The discussion above 

indicates that these mills have been designed to utilize pulp 

and paper sludges and use of that material as a fuel is an 

integral part of facility operations. Decisions regarding use 

and the right mix of fuel in any given day are based on the 
Page 249 of 319

boiler conditions, fuel availability, energy needs, air quality 

requirements and cost. 

Comment: The EPA requested information on the amount of 

pulp and paper sludge burned as fuel. 

In 2010, members of AF&PA burned 772,034 dry tons of pulp 

and paper sludge, which represents approximately 25 percent of 

the pulp and paper sludge generated by members of AFPA during 

the year.86 However, approximately 90 percent of the AF&PA member 

facilities that responded to their survey (42 out of 47) that 

use dewatered pulp and paper sludge as fuels do so at a 

significant rate (between 70-100 percent of these materials that 

are generated are burned). In fact, one third of the AF&PA 

facilities that responded to their survey (16) that burn pulp 

and paper sludges, burn 100 percent of the materials generated.87 

Response: As the commenter indicates, while 25 percent of 

pulp and paper sludges that are generated are used as fuels on 

an industry-wide basis, the vast majority of facilities that 

responded to the survey that use dewatered pulp and paper 

sludges as fuels do so at a significant rate. In light of the 

information on use of pulp and paper sludges, the agency finds 

that for those pulp and paper mills that burn a significant 

 

86 Docket EPA-HQ-OAR-2003-0119-2619. 

87 See April 4, 2012, letter from Timothy G. Hunt to James Berlow. A copy of 

this letter has been placed in the docket for today’s rulemaking.
Page 250 of 319

portion, that their use as a legitimate fuel is integral to the 

operation of the pulp and paper mill. The fact that these 

sludges meet the contaminant legitimacy criterion also, in the 

EPA’s view, shows that these sludges when burned on-site are not 

being discarded.

As discussed above, while the agency is not defining a 

specific percentage of dewatered pulp and paper sludges that 

would need to be burned to qualify for the categorical listing 

in section 241.4, the agency would consider the 42 mills that 

responded to the AF&PA survey as meeting the listing 

description. Where a facility has burned or burns in the future 

a significant portion of the dewatered pulp and paper sludges 

that are generated, the facility is clearly dependent upon the 

use of these materials as fuels in much the same way that wood 

manufacturing facilities are dependent upon the stream of 

resinated wood residuals to meet their energy demands. 

Specifically, we note that the percentage of overall use of pulp 

and paper sludges as a fuel at facilities burning a significant 

portion of the material (70 percent in the AF&PA comment above) 

is similar to the use of resinated wood within the wood products 

industry -- approximately 73 percent of resinated wood generated 

is either used as a fuel or is recycled back into the wood 
Page 251 of 319

manufacturing process.88 As noted above, mills that burn a 

significant portion of their dewatered pulp and paper sludges 

on-site as fuel in the future would also qualify for the listing 

description.89 

On the other hand, when a pulp and paper mill burns a 

relatively small percentage of their dewatered pulp and paper 

sludges on-site as a fuel (e.g., the five mills that responded 

to the AF&PA survey that burn less than 20 percent), the agency 

has determined that such sludges are not viewed the same by the 

mill operator in that they do not rely on the sludges for their 

energy value. As noted by one commenter, some mills may not 

produce pulp and paper sludge with sufficient fiber, such that 

the sludge is a viable fuel. Therefore, the agency finds that 

such pulp and paper sludge should not be included in the 

categorical listing in section 241.4.90 Those companies would 

need to make case-by-case determinations regarding legitimacy to 

support use as a fuel. 

 

88 See Materials Characterization Paper In Support of the Final Rulemaking: 

Identification of Nonhazardous Secondary Materials That Are Solid Waste –

Resinated Wood Products. Docket EPA-HQ-RCRA-2008-0329-1820.

89 While the Agency is not including a specific requirement for pulp and paper 

mills to document the amount of dewatered wastewater treatment residuals they 

burn on-site as a fuel, we would recommend that such pulp and paper mills 

include such documentation in case there are any questions as to whether the 

pulp and paper mills’ dewatered wastewater treatment residuals qualifies for 

the categorical listing in 241.4.

90 The Agency acknowledges that some portion of these pulp and paper sludges 

are land applied. While the Agency considers such uses as beneficial, such 

recycling is not integral to pulp and paper operations, and therefore, the 

Agency would not consider this form of recycling in determining whether a 

facility is recycling a significant portion of their pulp and paper sludges. 
Page 252 of 319

Comment: The EPA requested more data on contaminant levels 

– particularly chlorine and metals.

The NCASI undertook a thorough evaluation of data related 

to contaminant levels in pulp and paper sludge.91 NCASI looked at 

the most robust information about pulp and paper sludge which is 

found in the EPA’s Boiler MACT database. That database has pulp 

and paper sludge data comprised of nearly 5,280 records of 

individual data points corresponding to 46 AF&PA member pulp 

mills.

Table 8 of this preamble includes data from the EPA 

traditional fuels table as well as the EPA Boiler MACT database 

for pulp and paper sludge.

 

91 Docket EPA-HQ-OAR-2003-0119-2619.
Page 253 of 319

Table 8. Comparison of Traditional Fuel Contaminant 

Concentrations With Pulp Mill Sludge Data From the EPA’s Boiler 

MACT Database

Lit.

Sour

ce

Rang

e

1

Compou

nd

Un

it

s

Data from EPA OAQPS Databases Data from Boiler MACT 

Database, v. 72

Industrial Sludge 

NAICS 322

Coal Biomass Fuel Oils

Mi

n

Ma

x

Av

g.

Mi

n

Max

A

v

g

.

Mi

n

Ma

x

Av

g.

N

o

.

N

D

s

Mi

n

Ma

x

90

% 

UP

L

3

KM

4

Mea

n

ND -

26

Antimo

ny 

(Sb)

pp

m

ND

6.

9

1.

7

ND 6

0

.

9

ND

3.

8

3.

5

1

1

6

3

7

ND

3.

14

2.

0

0.4

5

ND -

80

Arseni

c (As)

pp

m

ND

17

4

8.

2

ND 298

6

.

3

ND 13 1.

3

3

7

6

9

4

ND

10

5.

0

70

.6

7.9

4

0.1 

- 15

Beryll

ium 

(Be)

pp

m

ND

20

6

1.

9

ND 10

0

.

3

ND 19 2.

3

3

5

8

1

0

2

ND

2.

6

1.

97

0.3

5

ND -

3

Cadmiu

m (Cd)

pp

m

ND 19 0.

6

ND 17

0

.

6

ND

1.

4

0.

4

3

8

5

5

3

ND

19

.0

8.

2

1.5

5

ND -

130

Chromi

um 

(Cr)

pp

m

ND

16

8

13

.4 ND 340

5

.

9

ND 37 3.

7

3

8

8

5 ND

17

0.

0

77

.3

17.

14

ND -

30

Cobalt 

(Co)

pp

m

ND

25

.2

6.

9

ND 213

6

.

5

ND

8.

5

1.

1

1

2

7

2

2

ND

14

.4

16

.7

3.7

8

ND -

340

Lead 

(Pb)

pp

m

ND

14

8

8.

7

ND 229

4

.

5

ND 52 4.

3

3

4

7

1

9

ND

20

1.

0

64

.2

11.

53

5 -

840

Mangan

ese 

(Mn)

pp

m

ND

51

2

26

.2 ND

15,

800

3

0

2

ND

32

00

11

8

3

6

9

3 ND

3,

31

0

2,

65

0

559

.8

ND -

1

Mercur

y (Hg)

pp

m

ND 3.

1

0.

09 ND 1.1

0

.

0

3

ND 0.

2

0.

02

3

9

7

4

0

ND 1.

40

0.

72

0.1

14

ND -

540

Nickel 

(Ni)

pp

m

ND 73

0

21

.5 ND 175

2

.

8

ND 27

0

24

.1

3

8

1

9 ND

18

0.

0

67

.7

14.

990

ND -

10

Seleni

um 

(Se)

pp

m

ND 74

.3

3.

4

ND 9

1

.

1

ND 4

0.

8

3

1

6

1

9

7

ND 6.

0

4.

5

0.9

0
Page 254 of 319

TSM

2,

06

7

92

.6

17,

098

3

3

0

.

9

3,

60

9

15

9.

5

2,

96

4

618

.5

TSM 

w/o Mn

1,

55

5

66

.4

1,2

98

2

8

.

9

40

9

41

.5

31

4

58.

7

Chlorin

e (Cl)

pp

m

ND

9,

08

0

99

2

ND 5,4

00

25

9

ND

1,

26

0

13

3

3

7

4

11 ND 48

00

2,

06

4

378

Total 

Halogen

s

pp

m

9,

25

8

1,

05

6

5,5

28

29

1

1,

27

4

14

2

2,

39

4

445

1

Nitroge

n (N)

g/

kg

13

.6

54

.0

15

.1

2.

2

4.6 3.

46

2.

0

3.

0

2.

25

2

6

0

0.

8

17

.7

26

.4 7.7

2

Sulfur 

(S)

g/

kg

0.

74

61

.3

13

.6 ND 6.1 0.70 ND

57

.0

8.

28

1

1

8

0 ND

6.

3

8.

8

3.0

The grey shaded cells indicate an outlier test was performed and 

the outlier(s) identified was confirmed based on further 

graphical observation (see further explanation below).

1Total range determined from literature sources - coal - Clarke 

and Sloss (1992); biomass - Energy Research Centre for the 

Netherlands, Phyllis Biomass database. 

http://www.ecn.nl/phyllis; oil - U.S. EPA (1999), Appendix B; 

2Boiler MACT Database sludge analysis data; 

3Chebyshev UPL for non-normal data sets; 

4 Kaplan-Meier; Selenium (Se) - with the Rosner's test (n > 25), 

for 1% significance level, one potential outlier was 560 ppm, 

which was rejected after graphical observation of the data. The 

next highest detect was 6 ppm.

Footnotes on Other Literature Data

1 Literature contains a value of 39.5 g/kg for nitrogen in 

biomass and 8.95 g/kg for nitrogen in fuel oils;

2 Literature contains a value of 8.7 g/kg for sulfur in 

biomass.
Page 255 of 319

The commenter indicates, as shown in the table, that 

contaminant levels in pulp and paper sludge are well within the 

ranges of metals found in traditional fuels. For all 11 HAP 

metals, except Mn, the 90 percent UPL value for sludges is less 

than the corresponding maximum for coal. For Mn, which is 

principally derived from biomass, the 90 percent UPL value for 

sludges is well below the maximum for biomass. This is also 

reflected in the TSM comparisons with and without Mn between 

coal, biomass and pulp and paper mill sludges. Chlorine and 

total halogens (Cl + Fl) in sludge compare favorably with both 

biomass and coal. Nitrogen and sulfur in sludge also compare 

favorably with coal, although the commenter also points out that 

the nitrogen and sulfur contents are generally not indicative of 

HAP formation potential for any fuel, and in the case of pulp 

and paper mill sludges in particular, the sulfur content of 

these sludges is typically in the inorganic sulfate form that 

predominantly ends up in the combustion ashes.

NCASI found a paucity of data on organics in pulp and paper 

sludge. Except for Ds/Fs, which had been evaluated extensively 

in the 1990s, organics are not expected to be found in pulp and 

paper sludges. Due to the changes in bleaching techniques which 

demonstrated significant reductions in the existence of Ds/Fs in 

sludge, testing for even dioxins has not been undertaken 
Page 256 of 319

recently. NCASI notes that of the data that do exist, organics 

are rarely found and those that are identified are frequently 

below the detection limit. 

Overall, the commenter states that contaminant levels in 

pulp and paper wastewater treatment residuals compare well to 

those found in traditional fuels. 

Response: Based on the information provided, the agency 

finds that pulp and paper sludges, meet the comparable 

contaminant criterion (241.3(d)(1)(iii)). The data confirms the 

conclusions in the NHSM final rule regarding chlorine and metals 

are comparable to the levels found in coal, which is a 

traditional fuel that may be burned in these facilities.

Comment: The EPA requested information on what steps the 

industry has taken to ensure the quality of pulp and paper mill 

sludge when used as a fuel at pulp and paper mills is consistent 

with that of a fuel product. 

Commenters state that pulp and paper mills that generate 

pulp and paper sludge do so as part of their compliance with the 

CWA requirements, as well as part of an effort to return as much 

wood fiber to use as possible, either as an input to the 

manufacturing process or as a fuel. The strategies that each 

mill uses to meet those requirements differ depending upon the 

type of product, the location of the mill and the specific 

standards established by the EPA and the respective states. 
Page 257 of 319

However, mills clean wastewaters prior to discharge, thus 

creating primary and a variety of secondary pulp and paper 

sludges, all of which capture wood fibers. Furthermore, the 

question of whether the quality of the pulp and paper sludge is 

appropriate for a particular mill is based on the boiler design. 

As such, there are some boilers well suited to burn it; others 

cannot burn the material.

At one commenter’s mill, for example, the company has 

invested over $7 million upgrading sludge drying and management 

equipment. The object of these large investments was not to 

remove all of the moisture in the sludge. Rather, it was to make 

sludge quality consistent with that of the wet biomass burned in 

its combination boilers. Either too much or too little moisture 

can have a deleterious effect on the boilers’ combustion. One 

mill recently installed a belt press to improve the reliability 

of its sludge management system and increase the average solids 

content of its sludge. Since then, the sludge has occasionally 

caused combustion problems in the boiler because it was too dry, 

necessitating additional quality control to optimize the 

sludge’s moisture content.

Another commenter stated they invested over $3 million to 

prevent unwanted materials from reaching the treatment process 

and being discharged in mill effluent or being incorporated into 

the pulp and paper sludge. Their mills make coated paper 
Page 258 of 319

products, the coatings consisting largely of clay and other 

minerals. Improved equipment and operating procedures have 

significantly lowered sewer losses of these materials, improving 

the quality of wastewater and reducing the ash content of these 

pulp and paper sludges. To further pollution prevention, their 

mills set stringent specifications for raw materials, such as 

sulfuric acid and caustic soda, which minimizes the introduction 

of trace amounts of heavy metals into the process.

From the standpoint of process control, the commenter 

stated that sludge management processes are continuous, enclosed 

and carefully controlled. In contrast, bark and wood chips may 

be exposed to the elements for extended periods before being 

burned. Depending on the season, hardwood bark can get “stringy” 

and become very difficult to process as fuel. Frozen bark or 

chips can jam or disable equipment. Purchased fuel can have 

excessive rocks or grit. It is difficult to control the quality 

of biomass burned in the commenter’s boilers. Sludge frequently 

exhibits less variability in quality than other types of 

biomass.

Response: Based on the information provided, the agency 

finds that, for facilities burning a significant portion of the 

dewatered sludge, use of the material is integral to the 

facility’s operations, particularly in the value these materials 

provide as a critical source of energy. At such facilities,
Page 259 of 319

sludge management processes are carefully controlled and the 

industry has taken the necessary steps to ensure the quality of 

pulp and paper mill sludge when used as a fuel at pulp and paper 

mills. On the other hand, for those pulp and paper mills that do 

not burn a significant portion of their dewatered wastewater 

treatment sludges, the agency does not believe that the same 

steps have been taken to ensure the quality of the pulp and 

paper mill sludge that is used as a fuel and thus, is not an 

integral part of the pulp and paper mill operations. 

Comment: The EPA requested information on what are the 

standard practices used to ensure pulp and paper sludge has 

meaningful heating value.

As noted in the October 2011 pulp and paper sludge paper 

the AF&PA submitted prior to the December 2011 proposal, the 

overwhelming majority of pulp and paper mills remove water from 

pulp and paper sludge prior to managing it in any way. Belt and 

screw presses are most commonly used in the industry. Some mills 

use steam heated filter presses. Some pulp and paper sludge is 

also further dried in steam heated rotary driers. As indicated 

previously, sludge drying takes place entirely within buildings 

where equipment necessary to produce suitable sludge is housed. 

Sludge burned in the boilers is transported to the boilers on 

feed systems designed to ensure sludge, biomass and other solid 

fuels are homogeneous, thoroughly mixed and not exposed to the 
Page 260 of 319

elements while being conveyed to the boilers. In all instances, 

the goal is to raise the solids content – and thus, Btu value.

Response: Based on these comments and other information in 

the record, the agency finds that facilities that burn a 

significant portion of these materials take the steps necessary 

to dewater the pulp and paper sludge and to manage such 

dewatered sludge to maintain its meaningful heating value and 

burn the sludge for energy recovery. 

Comment: The EPA requested information on how pulp and 

paper mill sludge is managed when shipped offsite.

There are several mills within the industry that have 

agreements with other facilities, primarily electric utilities 

that purchase pulp and paper sludges for use as biomass-based 

fuel. For the most part, these arrangements occur when there is 

a utility close to the pulp and paper mill because the cost of 

shipping such sludges long distances may be prohibitive. Pulp 

and paper sludges may be sent offsite when it is being used by 

other entities to produce another product, (including fuel 

pellets92), used for other purposes (land application, use as 

landfill cover), or for final disposal. Pulp and paper sludges 

are shipped by containers, truck or rail.

 

92 When pulp and paper sludges are sufficiently processed, and such processed 

material meets the legitimacy criteria, the processed materials are non-waste 

fuels whether burned within or outside the control of the generator. 
Page 261 of 319

Response: The agency recognizes that, as described above, 

some pulp and paper sludges are sent offsite for use as a fuel. 

However, the agency has restricted the categorical listing to 

those pulp and paper sludges that are burned on-site because the 

agency has minimal information on offsite use of these 

materials. In fact, the pulp and paper industry indicates that 

the great majority of these sludges, when burned as a fuel, are 

burned on-site. Also, in the few instances that the pulp and 

paper industry discussed in their comments that these materials 

were shipped offsite, they seem to be sent to other industries. 

The fact that these sludges are sent to other industries would 

not necessarily disqualify those dewatered pulp and paper 

sludges from being considered for listing categorically. 

However, the agency does not have sufficient information to make 

any determination.93

Comment: For reasons stated previously in comments on the 

June 2010 proposed rule, one commenter argues that pulp and 

paper sludges are waste when burned regardless of whether it is 

burned by the company that generated it and regardless of 

whether it meets the EPA’s legitimacy criteria. Paper mill 

sludge is a waste because it is discarded within the meaning of 

RCRA.

 

93 We note that in the situation where pulp and paper sludges are transferred 

beyond the control of the generator, a facility may also petition the Agency 

to receive a non-waste determination, as appropriate. 
Page 262 of 319

The EPA’s description of pulp and paper sludge shows that 

it remains a waste even under the agency’s own definition of 

discard. First, the EPA acknowledges that pulp and paper mills 

have no use for pulp and paper sludge; the fibers it contains 

are “too short to be suitable for papermaking and it contains 

microorganisms that feed on organic material in the wastewater 

stream.” 94 Second, the fact that paper mill sludge comes from 

“the wastewater stream,”95 in itself confirms that it is a waste.

Third, the EPA’s discussion of the contaminant levels in 

paper mill sludge shows substantial variation in chlorine 

levels. Where the EPA encounters such variability in the course 

of setting floors for CISWI units in the very same Federal 

Register notice, the agency uses a 99th percent UPL to assure 

that the level it chooses will not be exceeded. Yet, where the 

EPA encounters variability in the chlorine levels in pulp and 

paper sludge – variability that could lead to significantly 

higher emissions of chlorinated pollutants, such as HCl and 

dioxins – the agency simply dismisses it without further ado. 

The EPA’s disparate treatment of the variability of emissions 

for floor setting and of the chlorine levels in pulp and paper 

sludge for the purposes of considering a categorical declaration 

that such sludge is not a waste is unexplained and arbitrary.

 

94 See 76 FR 80485.

95 Id.
Page 263 of 319

If the agency believes that such variability exists, it 

should be concerned about the possibility that some sludges may 

have far higher chlorine levels than it assumes – as, indeed, 

the record shows some sludge does – and should take steps to 

ensure that this is not the case before it even considers an 

exemption. Indeed, the agency’s failure to examine this 

possibility renders the existing rule, which allows generators 

to burn their own sludge, arbitrary and capricious.

Fourth, the EPA admits that sludge contains extremely low 

heating values, so low in some instances as to flunk the 

agency’s legitimacy criteria. That sources typically dewater 

their sludges does not make these sludges any less a waste, even 

under the agency’s own definition of discard. The EPA does not 

say what the heating value of the sludges is after dewatering, 

nor does it make any difference what the “dry weight” heating 

value of sludges might be, as they are not at “dry weight” when 

burned. The reality is that paper mills find it cheaper to burn 

their sludges than to dispose of them safely and that because 

these sludges are largely “wastewater” and contain high levels 

of chlorine and other contaminants, burning them requires large 

quantities of other fuel and generates high levels of pollution.

Response: The agency disagrees with the commenter that all 

pulp and paper sludges are wastes fuels when combusted. To the 

extent comments were submitted in response to the March 2011 
Page 264 of 319

final rule, the agency need not respond. Below, the EPA responds 

to the new points raised in the comments. 

With respect to the particular arguments on the categorical 

listing, the agency disagrees that the sludge remains a waste 

even under the agency’s own definition of discard. The comment 

is incorrect when it states that the EPA has acknowledged pulp 

and paper mills have no use for pulp and paper sludge because 

the fibers it contains are “too short to be suitable for 

papermaking and it contains microorganisms that feed on organic 

material in the wastewater stream.”96 In the proposed rule, we 

stated that fibers that end up being too short can be 

detrimental to paper quality. Although this would not be 

suitable for papermaking, these sludges are a valuable resource 

as energy-containing secondary materials as discussed in detail 

in the comments above. As much as 50 percent of the sludge is 

composed of wood fibers which are similar in content to other 

types of biomass fuel combusted. 

Further, the agency disagrees that pulp and paper mill 

sludges are wastes because they are contained in a “wastewater” 

stream. The D.C. Circuit in, API v. EPA, 216 F.3d at 58, 

rejected the proposition that the mere presence in a wastewater 

stream makes a material a waste. In API, the D.C. Circuit 

criticized the EPA for not saying why it concluded that the 

 

96 See 76 FR 80485.
Page 265 of 319

disposal motivation, compliance with water quality standards, 

predominated over the recycling motivation, recovery of oil from 

primary wastewater treatment. Plainly, the mere presence of oily 

material in wastewater did not make the oil a waste. In this 

case, the EPA has found in its categorical listing that the 

motivation for burning the pulp and paper sludge is to use its 

inherent value as a fuel and not for disposal. Comments have 

provided the agency with information that facilities that burn a 

significant portion of these sludges consider them to be an 

integral part of their production process, particularly in the 

value these materials provide as a critical source of energy. We 

disagree that the disposal motivation predominates over the true 

value of these sludges as an important fuel, integral to the 

production processes. 

The EPA also disagrees that the treatment of the 

variability of emissions for floor setting and of the chlorine 

levels in pulp and paper sludge for the purposes of considering 

a categorical declaration that such sludge is not a waste, is 

unexplained and arbitrary. The agency notes that, rather than 

dismissing the variability of chlorine levels in pulp and paper 

sludges, it has considered all available data—including data on 

variability—and reached the conclusion that contaminant levels 

in pulp and paper sludges are comparable to or lower than those 

in the appropriate traditional fuel(s). The EPA acknowledges 
Page 266 of 319

that, based on data submitted to the agency since promulgation 

of the March 2011 final rule and presented in the December 2011 

proposed rule, chlorine levels in paper mill sludge show 

substantial variation. This is an important factor to consider 

when making a categorical non-waste determination and the agency 

has considered mean concentrations, the range of concentrations, 

and variability when analyzing pulp and paper sludges. 

As stated in the proposed rule and information in the 

rulemaking record, data for pulp and paper sludges show mean 

chlorine concentrations of 361 ppm, well below the mean of 992 

ppm observed in coal. Data for pulp and paper sludges also show 

maximum chlorine concentrations of 4,800 ppm, well below the 

maximum of 9,080 ppm observed in coal and below the maximum of 

5,400 ppm observed in untreated wood and biomass materials. The 

variability of chlorine levels in pulp and paper sludge is 

demonstrated by a standard deviation of the mean of 661 ppm.97 98

This variation in chlorine levels, although high, does not 

discount the fact that both average and maximum chlorine 

concentrations in pulp and paper sludge are lower than those in 

coal which is defined as a traditional fuel. 

 

97 See 76 FR 80485.

98 Contaminant Concentrations in Traditional Fuels: Tables for Comparison, 

November 29, 2011, can be found at 

http://www.epa.gov/epawaste/nonhaz/define/index.
Page 267 of 319

The comment also implied that the EPA should use the 99 

percent UPL, as is used to set the CISWI floors, to ensure that 

these pulp and paper sludges do not contain excessive 

contaminant levels. The agency disagrees that any one 

statistical tool or comparison methodology will fit every 

situation given the variety of NHSMs, traditional fuels, 

contaminants and combustion units that exist. Nevertheless, the 

agency has calculated the 99 percent UPL for chlorine levels in 

pulp and paper sludge in response to the comment and come to the 

same conclusion. The 99 percent UPL for the same dataset of 93 

samples analyzed in the proposed rule would be 6,970 ppm, a 

value below chlorine concentrations observed in coal.99

Finally, we disagree that pulp and paper sludge contains 

extremely low heating values that would fail the agency’s 

legitimacy criteria. In terms of meeting the legitimacy criteria 

for a meaningful heating value, the agency indicated in the NHSM 

final rule that pulp and paper sludges have a heating value of 

between 3,300–9,500 Btu/lb, on a dry basis -- no specific 

information having been submitted on the ‘‘as fired’’ heating 

value of these materials. The final rule concluded that pulp and 

paper sludges meet the legitimacy criterion for being managed as 

a valuable commodity as they are dewatered to increase their 

 

99 The 99 percent Chebyshev UPL for non-normal datasets was calculated using 

EPA’s ProUCL 4.0 Software available at 

http://www.epa.gov/nerlesd1/tsc/software.htm. 
Page 268 of 319

energy value, collected on a continual or frequent basis (as 

produced), and further processed and consolidated, including the 

removal of biosolids. Further, as discussed in detail above, 

where a facility is burning a significant portion of the 

dewatered pulp and paper sludges that are generated as fuel 

rather than other purchased biomass or fossil fuels, pulp and 

paper sludges are integral to the facility’s operations and the 

facility is clearly dependent upon the heating value of these 

materials.100 Thus, we find, as discussed in the final rule, that 

pulp and paper sludges are not discarded and generally meet the 

meaningful heating value legitimacy criterion (46 FR 15488).

b. Coal Refuse101

In the 2011 NHSM final rule, the EPA included currently 

generated coal refuse within the definition of traditional fuel 

codified in 40 CFR 241.2. In discussing its determination that 

currently generated coal refuse is a traditional fuel, the 

agency said, “the fact that coal refuse has been used and 

managed as a fuel for thirty years when coupled with the fact 

that coal refuse is unique from other non-hazardous secondary 

 

100 The final rule notes that meaningful heating value is derived from an NHSM 

with energy content lower than 5000Btu/lb if the ERU can cost-effectively 

recover meaningful energy from the NHSM used as fuel (76 FR 15541). 

101 Coal refuse refers to any by-product of coal mining or coal cleaning 

operations, consisting primarily of non-combustible rock with attached coal. 

Due to advances in technology over the past century, the processing of coal 

has evolved, such that materials that are now generated in the coal mining 

process, which would have been considered coal mining rejects in the past and 

discarded in waste piles, are now handled and processed as coal. 
Page 269 of 319

materials in that it is a byproduct of fuel production processes 

and is itself a raw material that can be used as a fuel leads us 

to determine that coal refuse that is currently generated and 

used as a fuel should be considered a traditional ‘alternative 

fuel.’”102 

The 2011 NHSM final rule also determined that coal refuse 

that has been placed in legacy piles would not meet the 

definition of traditional fuels, as they clearly have been 

discarded in the first instance.103 Since coal refuse recovered 

from legacy piles is subjected to the same operations that are 

used to process virgin coal, which serve to both increase energy 

values, as well as reduce contaminants, the EPA determined that 

such processes were sufficient to meet the definition of 

“processing,” as codified in 40 CFR 241.2, and such recovered 

coal refuse would not be considered a solid waste when used as a 

fuel in a combustion unit provided those materials satisfy the 

legitimacy criteria.104

The 2011 NHSM final rule also stated our belief that coal 

refuse recovered from legacy piles contains contaminants at 

levels that are comparable to or lower than coal refuse that is 

currently generated, as the recovered coal refuse is subject to 

the same processes as currently-generated coal refuse in order 

 

102 See 76 FR 15507.

103 Id.

104 See 76 FR 15509.
Page 270 of 319

to meet the same fuel specifications. Since promulgation of the 

2011 NHSM final rule, the agency has further clarified that it 

believes that coal refuse recovered from legacy piles that is 

processed and managed in the same manner as currently generated 

coal refuse satisfies the legitimacy criteria.105

Having determined that coal refuse recovered from legacy 

piles that is processed and managed in the same manner as 

currently generated coal refuse satisfies the legitimacy 

criteria, the 2011 proposed rule solicited comment on whether to 

categorically list post-processed coal refuse from legacy piles 

as a non-waste fuel in 40 CFR 241.4(a). However, the EPA made it 

clear that it was not reopening any other issues regarding coal 

refuse. Other comments regarding coal refuse are responded to in 

the record for the final rule. In this part of the preamble, we 

are only responding to the issue of whether coal refuse 

processed from legacy piles should be considered a non-waste 

fuel on a categorical basis. Accordingly, the EPA is not 

responding in this preamble or the Response to Comment document 

on issues regarding whether coal in legacy piles are traditional 

fuels. 

Comment: One commenter states that not every material that 

is discarded is treated as solid waste under the rule. For 

 

105 See August 15, 2011, letter to Jeff A. McNelly, ARIPPA (cited in the 

proposed rule: 76 FR 80486).
Page 271 of 319

example, the EPA includes numerous materials within its 

definition of “traditional fuels” and “clean cellulosic biomass” 

that are commonly understood as used, discarded, and abandoned, 

listing, for example, corn stover, peanut shells and certain 

types of demolition materials. The commenter argues that each of 

these materials is either discarded or has filled its original 

purpose and may be collected by a different party for a 

different purpose (i.e., use as a fuel).

The commenter continues that although the agency has ample 

authority to exempt certain articles from classification as 

solid wastes, it did not consistently apply the term “discarded” 

in the context of legacy coal refuse. For example, the EPA 

recognized that on-specification used oil and clean C&D 

materials should be treated as traditional fuels when combusted 

for energy generation. Thus, the commenter urges the agency to 

revisit its application of the “discard” principle and treat all 

coal refuse, regardless of when they were generated and 

regardless of processing to be fuels and not wastes. 

Response: The EPA disagrees with the comment, which seems 

to misunderstand the purpose of this rulemaking action. If the 

agency determines in this rulemaking that a material is a solid 

waste when combusted, the unit combusting that material would be 

subject to emissions standards issued under CAA section 129 even 

if burned as a fuel. A material is not discarded simply because 
Page 272 of 319

it is no longer used for its original purpose. It may be used as 

a fuel product by another party, providing the conditions the 

EPA has explained in the rule apply. In such a case, the reused 

material is not a waste. Further, the agency is not exempting 

any materials from the definition of solid waste. The EPA is 

only describing the kinds of materials that are wastes when 

burned in combustion units, even if they are burned for energy 

recovery. The EPA consistently applies the concept of “discard.” 

Materials listed as examples of clean cellulosic biomass 

cited by the commenter have not been discarded in the first 

instance, as is clearly the case for coal refuse abandoned in 

legacy piles. While some materials have filled their original 

purpose, that fact, in and of itself, does not equate to 

discard. Clean cellulosic biomass is considered to be a type of 

“alternative fuel” within the definition of “traditional fuel.” 

Such alternative fuels are developed from virgin materials that 

can now be used as fuel products.106 This applies to the examples 

mentioned by the commenter, including corn stover, peanut shells 

and clean construction and demolition wood. Further, coal refuse 

mined today that would have previously been abandoned in piles 

are also alternative fuels that are now grouped in the 

traditional fuel category because of new technology. This is 

 

106 See definition of traditional fuels, as codified in 40 CFR 241.2. We note 

that the December 2011 proposal did not solicit comment on the definition of 

traditional fuels. 
Page 273 of 319

separate from coal in legacy piles that have been traditionally 

wastes.

Further, there is a clear difference between the management 

of the listed examples of clean cellulosic biomass and coal 

refuse abandoned in legacy piles. For example, the commenter 

characterizes corn stover as “typically left in the field to 

decay” and thus discarded. The EPA assumes this statement is 

based on the historic use of leaving corn stover in the field as 

a cover to reduce erosion and for nutrient content.107 As noted 

by the agency previously, over the course of this rulemaking, an 

emerging market for corn stover and other primary and secondary 

agricultural residues is for use as a heat and power source for 

the production of corn and cellulosic ethanol.”108 When the 

determination is made to use corn stover for its fuel value, the 

materials are managed differently than merely “left in the field 

to decay.” If there were legacy piles of such materials, they 

too would have to be treated as wastes while in the legacy 

piles. We would also note that it is not unreasonable to expect 

that agricultural materials, such as corn stover, may be left on 

the field until there are sufficient amounts of those materials 

 

107 See Petrolia, Dr. Daniel R., “Economics of Crop Residues: Corn Stover.” 

June 2009. A copy of this document has been placed in the docket to today’s 

rulemaking. 

108 See Materials Characterization Paper in Support of the Final Rulemaking: 

Identification of Nonhazardous Secondary Materials That are Solid Waste, 

Biomass—Agricultural Residues and Food Scraps.” February 3, 2011. A copy of 

this document can be found in the docket for today’s rulemaking. 
Page 274 of 319

to be collected, baled and transported. This is clearly a 

different scenario from coal refuse left in place in piles with 

no purpose other than abandonment and clearly managed as a waste 

for decades. 

With respect to used oil, the agency has already explained 

in the final March 2011 rule the difference between onspecification and off-specification used oil as applied to the 

definition of solid waste. The on-specification used oil is 

considered an alternative fuel that has not been abandoned and, 

by regulation, may be burned with no more restrictions than 

refined product oil. Off-specification used oil is specifically 

described in the EPA’s regulations as a material that may only 

be burned in certain combustors because it exceeds contaminant 

levels established under part 279, rendering it offspecification and, accordingly, evaluated under part 241 to 

determine its waste/non-waste status.109. 

Comment: One commenter argues that off-specification tires 

are analogous to legacy coal refuse to the extent they are set 

aside and not used immediately by the factory. Since the agency 

proposes to include off-specification tires within the 

definition of “established tire collection program” and not 

 

109 Note that Section III.D.2.c of today’s preamble discusses circumstances 

under which off-specification used oil may use coal data when making 

contaminant comparisons.
Page 275 of 319

consider these materials to be a solid waste when used a fuel, 

the agency should treat legacy coal refuse similarly.

Response: We disagree with the commenter that coal refuse 

abandoned in legacy piles is analogous to the handling and 

management of off-specification used tires. Coal refuse that has 

been placed in legacy piles decades ago has clearly been 

abandoned, thrown away and thus, discarded and historically 

managed as a waste. On the other hand, the agency has 

information that tire manufacturers that have produced offspecification tires (including factory scrap) have contractual 

agreements in place to ensure these materials are collected, 

managed and transported to the combustor. In fact, it is the 

requirement that scrap tires (including off-specification tires) 

be managed pursuant to established tire collection programs that 

ensures these materials are managed as a valuable commodity in 

order to meet the categorical non-waste determination codified 

in 40 CFR part 241.4(a). 

Further, as we have noted elsewhere in today’s preamble, to 

the extent that these off-specification tires are discarded, 

such as in tire piles, they would be considered solid waste in 

that they have been discarded, and would not be included within 

the categorical listing of “scrap tires that are not discarded 

and are managed under the oversight of established tire 
Page 276 of 319

collection programs, including tires removed from vehicles and 

off-specification tires.” 

Comment: One commenter states that the EPA, consistent with 

the intent of RCRA, should be encouraging the use of legacy coal 

refuse, not hampering them. The commenter argues that 

characterizing coal refuse in legacy piles as a solid waste 

could subject legacy coal refuse piles to additional federal and 

state requirements and potentially result in the piles being 

classified as open dumps or solid waste management units. 

Further, combustors of legacy coal refuse and their supplies 

would also be more likely to be subject to citizen suits under 

RCRA 40 CFR 7002. This commenter argues that the determination 

that unprocessed legacy piles are different—and should be 

regulated differently—than coal refuse generated from current 

mining operations is illogical because the characteristics of 

the materials are the same. Thus, although the EPA takes the 

position that subjecting legacy coal to the types of operations 

that are used to process virgin coal is sufficient to convert 

the legacy coal refuse from solid waste into a non-waste fuel, 

the initial designation as solid waste risks regulatory 

confusion regarding the status of the numerous piles of legacy 

coal refuse. 

Response: This comment is clearly beyond the scope of this 

rulemaking proceeding. In the first place, legacy coal piles 
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are, indeed, wastes. How they may be treated when they are in 

the piles is clearly beyond the scope of this rule. This rule 

deals with how the legacy coal is to be treated when it is taken 

from the piles and burned for fuel.

Comment: While supporting the concept of a categorical 

listing for legacy coal refuse, a few commenters argued that the 

agency should not require that legacy coal refuse be “processed” 

in order to be considered a non-waste fuel. One commenter noted 

that the EPA does not require traditional fuels or resinated 

wood to undergo processing to be treated as a fuel, even though 

many of those materials would be understood to be discarded.

Another commenter noted that the term “post-processing,” 

which was used in the proposal as a shorthand description of 

legacy coal refuse that has undergone processing, is too vague 

and should be eliminated so the use of extracted coal refuse 

undergoing further processing at the generating facility is not 

discouraged. If applied too literally, the commenter continued, 

any “post-processing” provision being imposed on treating legacy 

coal piles as fuel would not benefit the CFB community and could 

hinder the usage of these piles as fuels. The commenter argues 

that the term “post-processing” could be interpreted as 

requiring processing at the coal refuse excavation site which 

would not be determinative of any relevant characterization of 

the coal refuse or its intended use as fuel.
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Response: In the 2011 NHSM final rule, the EPA discussed 

how a NHSM, once discarded, can be processed into a non-waste 

fuel.110 The proposed rule did not solicit comment on either the 

concept of processing a discarded NHSM into a non-waste fuel or 

the definition of “processing” itself, as codified in section 

241.2. Therefore, the agency does not address the concept or 

definition of processing in this final rulemaking.

Again, however, the comment suggests a need to clarify the 

nature of the rulemaking exercise that the EPA is currently 

engaged in. First, we disagree with the commenter’s 

characterization that many of the traditional fuels and 

resinated wood should be understood to be discarded. Traditional 

fuels, by definition, are not discarded.111 If clearly discarded 

(e.g., a barrel of fuel oil dumped), even a traditional fuel 

would have to be processed per the part 241 regulations in order 

to be a non-waste fuel. However, it is precisely because of 

their fuel value that makes it unlikely that traditional fuels 

will be discarded. We also disagree that resinated wood is 

discarded prior to being or when used as a fuel in a combustion 

 

110 See 76 FR 15474-15477. 

111 See last sentence of “traditional fuels” definition, as codified in 241.2: 

“[Traditional] fuels are not secondary materials or solid wastes unless 

discarded” (emphasis added). 
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unit. For a discussion of why we believe resinated wood is a 

non-waste fuel, please see section III.E.3.b of this preamble.112 

As noted above, coal refuse abandoned in legacy piles has 

clearly been discarded in the first instance because the coal 

preparation technology did not yet exist that could utilize 

these materials for their fuel value. Thus, legacy coal refuse 

would have to be processed into a non-waste fuel. However, the 

agency has previously recognized the uniqueness of coal refuse 

in that it is a byproduct of fuel production processes and is 

itself a raw material that can be used as a fuel.113 In the 2011 

NHSM final rule, the agency determined that coal refuse that is 

recovered from legacy piles and used as fuel that is subjected 

to the types of operations that are used to process virgin coal 

or currently generated coal refuse would meet our definition of 

processing as codified in 40 CFR part 241.2.114 

 

112 See also discussion included in the 2011 NHSM final rule (76 FR 15499-

15502).

113 See 76 FR 15507, which states, “Coal refuse is unique, however, from other 

non-hazardous secondary materials addressed in this rulemaking, as it is 

generated in the process of producing fuels (i.e., the mining of coal for use 

as fuel) and its subsequent use and value as a secondary material is also as 

a fuel. Since the primary product of a coal mining operation is itself a 

fuel, we consider coal refuse to be more akin to a raw material that is 

subsequently processed and utilized to produce a fuel. In other words, coal 

refuse is different from other non-hazardous secondary materials, such as 

used tires or resinated wood residuals, in that it is generated in the 

production of fuel and can be used itself as a fuel (and in fact has never 

been used for anything else).”

114 See 76 FR 15509. In addition, subsequent to the 2011 NHSM final rule, the 

EPA has reiterated this determination. See August 15, 2011, letter to Jeff A. 

McNelly, ARIPPA (cited in the proposed rule: 76 FR 80486).
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As the processing that is required is no different than 

what currently-generated coal refuse is subject to, we do not 

believe the processing requirement would hinder the usage of 

coal refuse piles. The agency believes the only additional 

“processing” step is the actual extraction or recovery of the 

coal refuse from the legacy piles. To the extent that the term 

“post-processing” could be misconstrued as requiring an 

additional processing step at the extraction site or otherwise 

as compared to currently generated coal refuse, this was not the 

agency’s intent. Rather, we have included the concept of 

“processing” in the categorical non-waste determination for 

legacy coal refuse, as legacy coal refuse was clearly discarded 

and, prior to processing, is a solid waste. That said, we 

clarify again today that coal refuse recovered/removed from 

legacy piles that is processed in the same manner as currently 

generated coal refuse would meet the definition of processing as 

codified in section 241.2. No additional processing is required 

given the uniqueness of coal refuse. For commenters suggestions 

regarding the explicit wording of the categorical listing for 

legacy coal refuse, see additional response to comments below.

Comment: In support of the agency’s soliciting comment on 

whether to add legacy coal refuse to the list of categorical 

non-waste fuels proposed in 40 CFR part 241.4, one commenter 

states that once removed from the physical mining location, 
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legacy coal refuse and currently-generated coal refuse are 

indistinguishable. Thus, coal refuse from legacy piles will be 

managed in the same manner as coal refuse, will have similar 

heating value as coal refuse and be used as a fuel in a 

combustion unit that recovers energy and can be expected to have 

similar contaminant levels as coal refuse because it is 

ostensibly the same material. 

Response: We agree that coal refuse recovered/removed from 

legacy piles and processed in the same manner as currently 

generated coal refuse would meet both the definition of 

processing and the legitimacy criteria. Thus, we have determined 

to list “coal refuse that has been recovered from legacy piles 

and processed in the same manner as currently-generated coal 

refuse” to the list of categorical non-waste fuels codified in 

part 241.4(a) of today’s rulemaking. The rationale for adding 

this NHSM to the list of non-waste fuels follows the reasoning 

finalized in part 241.4(b) in today’s rulemaking. We agree with 

the reasoning of the comment and have, in fact, arrived at the 

very same reasoning in support of the categorical listing.

Comment: One commenter argued that the EPA should treat 

legacy coal refuse as fuels, since they are chemically 

identical, if not superior fuels, to currently generated coal 

refuse that the agency considers to be a traditional fuel, per 

the definition codified in 40 CFR 241.2. 
Page 282 of 319

Response: Again, the EPA must explain a misunderstanding 

expressed by the commenter. The comment seems to consider that 

material is either a “fuel” or a “waste” and misses the point 

that the distinction in this rulemaking is between a “product”

and a “waste” fuel. Fuels may be wastes. The point is that the 

coal that has been abandoned in piles is a waste. However, the 

EPA has determined that once processed that coal is either 

identical (or maybe even superior) to currently mined materials 

that would have become refuse in the past. 

The EPA agrees with, and has adopted, the same reasoning 

expressed by the commenter that the processed material is a 

product fuel. The disagreement between the EPA and the comment 

is the status of the legacy piles and the nomenclature of the 

coal finally burned. The coal is a processed fuel product, not a 

traditional fuel. 

Comment: One commenter stated that there are “other 

relevant factors” that the EPA should consider when determining 

whether coal refuse from legacy piles should be categorically 

listed as a non-waste fuel. Specifically, the commenter believes 

that the EPA should consider the “overwhelming resultant 

environmental improvements” associated with the cleanup of 

abandoned coal refuse piles, including the reduction of fire 

hazards and contaminant, siltation, and solids releases into the 
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environment, as an “other relevant factor” as it considers 

listing legacy coal refuse as a non-waste fuel in part 241.4. 

Response: The EPA’s decision to include processed legacy 

coal refuse to the list of non-waste fuels in part 241.4(a) was 

based on the fact that such materials meet the definition of 

processing and the legitimacy criteria. We do not need to 

balance “other relevant factors” in making this determination, 

as would be appropriate under an analysis conducted under 

section 241.4(b)(5)(ii). 

Comment: The EPA received a few comments regarding the 

specific wording of how coal refuse recovered from legacy piles 

should be identified and described in part 241.4(a) should the 

agency determine to categorically list this NHSM pursuant to 

part 241.4(a). One commenter suggested inserting the following 

text as a subsection within part 241.4(a): “Coal refuse that 

does not constitute currently-generated coal refuse, but that is 

processed in the same manner as currently-generated coal 

refuse.” As previously discussed, another commenter stated that 

the term “post-processed” was vague and could be interpreted to 

require additional processing that would hinder the usage of 

legacy coal refuse piles. Still another commenter suggested 

referencing the SMCRA in a categorical non-waste determination 

for coal refuse, which would ensure that the coal refuse is a 
Page 284 of 319

fuel and minimize overlapping regulatory jurisdiction that could 

evolve. 

Response: As discussed above, we have determined to list 

“coal refuse that has been recovered from legacy piles and 

processed in the same manner as currently-generated coal refuse” 

to the list of categorical non-waste fuels, as codified in part 

241.4(a) of today’s rulemaking. We believe this language 

accurately captures the scope of materials at issue and what 

must occur for the material to be categorically characterized as 

a non-waste fuel. That is, this categorical listing only applies 

to coal refuse that has been discarded in the first instance in 

legacy piles, subsequently recovered or removed from the discard 

environment and subjected to the same processes and operations 

as currently generated coal refuse.115 Further, this language 

should alleviate any concerns that the term “post-processed” is 

vague since that term is not being used within this provision as 

finalized today.

We do not agree with the comments that a categorical 

listing for legacy refuse should specifically reference SMCRA. 

As we noted in the preamble to the 2011 NHSM final rule, while 

the EPA recognizes that SMCRA is concerned with the management 

 

115 We note that it would not be appropriate to include currently generated 

coal refuse within this categorical non-waste determination, as we have 

previously determined and continue to believe that currently generated coal 

refuse is a traditional fuel. 
Page 285 of 319

and removal of coal refuse piles at mining sites, SMCRA does not 

address the issue of “discard,” which is critical to the 

definition of solid waste under RCRA.116 Thus, a specific 

reference to SMCRA would be inappropriate as well as confusing. 

Further, we believe that a specific reference to SMCRA would be 

in fact more burdensome than the language of the categorical 

listing being codified today, which simply states that legacy 

coal refuse must be processed in the same manner as currentlygenerated coal refuse, regardless of whether such processing is 

done pursuant to SMCRA. 

c. Manure

In the 2011 NHSM final rule, the EPA stated that based on 

the information provided, we could not make a blanket 

determination that all manure is a traditional fuel or that it 

is a solid waste. However, upon reviewing the few comments and 

data received, we concluded that animal manure that is used as a 

fuel “as generated” does not satisfy the legitimacy criteria, 

and thus, if combusted “as generated,” would be a solid waste.117

However, the agency also noted that there were circumstances 

where manure would not be considered a solid waste when burned 

as a fuel for energy recovery, specifically: (1) when the manure 

remained within the control of the generator and met the 

 

116 See 76 FR 15510.

117 See 76 FR 15480.
Page 286 of 319

legitimacy criteria; (2) when the manure was sufficiently 

processed (e.g., via anaerobic digestion or gasification 

processes) and the resulting material met the legitimacy 

criteria; and (3) when a facility received a determination from 

the agency pursuant to 241.3(c) stating that its manure was a 

non-waste when used as a fuel. For further discussion regarding 

our characterization of manure, see the preamble to the 2011 

NHSM final rule (76 FR 15479-15482).

In the December 2011 proposed rule, the agency noted that 

some parties have identified the potential of manure to not be 

considered a solid waste. We, therefore, invited parties to 

present information, including data demonstrating that manure is 

not discarded either through the existing non-waste petition 

process or the proposed categorical determination process.118 The 

agency received no information or data that would allow it to 

consider proposing to list manure categorically as a non-waste 

fuel.119 Therefore, we are not taking any action in the 

rulemaking with respect to manure. However, the agency did 

receive several comments from one commenter which we will 

 

118 See 76 FR 80472.

119 In the preamble to the proposed rule, the agency indicated the type of 

information and data that should be submitted to categorically list manure as 

a non-waste fuel. Specifically: (1) the extent that use of the NHSM has been 

integrally tied to the industrial production process—information can include 

combustor design specifications, the extent that the use of the material is 

integrated across the industry and the extent that use of the NHSM is 

essential to the industrial process and/or (2) the extent that the NHSM is 

functionally the same as the comparable traditional fuel and (3) other 

relevant factors. 
Page 287 of 319

respond to below.

Comment: The commenter states that dried animal manure 

should be included as a non-waste with the other fuels in 40 CFR 

241.4(a). The commenter contends that there is no evidence that 

any animal manure is discarded, let alone sent to landfills. 

Manure is generally used as fertilizer on fields, although an 

important secondary purpose is for energy recovery/generation. 

In addition, the commenter states there are several known 

instances of additional plans for animal manure energy projects 

that are designed specifically to recover energy, including 

government funded projects. 

The commenter notes that after drying, animal manure has a 

meaningful Btu value equal to or above that of other biomass 

that the EPA has determined to be a non-waste fuel (e.g., 

bagasse). The commenter also notes that there are contracts in 

place for livestock and poultry producers to supply manure to 

the combustor. 

Regarding contaminants in manure, the commenter states that 

the amount of contaminants is limited because the vast majority 

of applicable contaminants are directly related to the 

contaminants contained in the biomass consumed by the animals. 

The EPA has not presented any evidence that facilities are 

combusting manure in order to discard chlorine or nitrogen, the 

two contaminants identified by the EPA. These concentrated 
Page 288 of 319

contaminants are no different than what occurs in the production 

of “byproducts of ethanol natural fermentation processes,” which 

the EPA is now proposing to include in the definition of “clean 

cellulosic biomass.” Based on a “balancing of the legitimacy 

criteria and other such relevant factors,” the EPA‘s new 

standard, animal manure should be included in the 40 CFR 

241.4(a) fuels list, along with resinated woods and scrap tires.

Response: We disagree with the commenter on several points 

and do not believe that the case has been made to include animal 

manure as a categorical non-waste fuel in 40 CFR 241.4(a). 

First, in the 2011 NHSM final rule, we previously determined 

that animal manure that is used as fuel, “as generated,” would 

not satisfy the legitimacy criteria. This conclusion was based 

on the fact that such material likely would not satisfy the 

meaningful heating value and contaminant legitimacy criterion.120

Thus, we believe that the burning of such materials (as 

generated) would not be legitimate and would be seen as burning 

for discard. Further, the agency has never stated that a NHSM, 

including animal manure, has to be landfilled in order to be 

discarded, as the commenter implies. Regarding the use of manure 

as fertilizer, we have been clear that this rulemaking does not 

address that secondary use. The 2011 NHSM final rule states, “We 

recognize that manure may also be beneficially used in other end 

 

120 See 76 FR 15480-15481.
Page 289 of 319

uses, such as a fertilizer... EPA is not making any determination 

whether non-hazardous secondary materials are or are not solid 

wastes for other possible beneficial end uses. Such beneficial 

use determinations are generally made by the states for these 

other beneficial uses, and EPA will continue to look to the 

states to make such determinations.”121

The commenter notes additional plans for animal manure 

energy projects; however the fact that there are plans for 

future projects does not support a categorical non-waste 

determination today. As the EPA has acknowledged, facilities may 

be able to demonstrate that they satisfy the legitimacy 

criteria, either through a self-determination if the manure 

remains within the control of the generator or through the part 

241.3(c) non-waste determination petition process. Thus, any 

future energy project using animal manure as fuel could utilize 

either of these options for determining that the manure is a 

non-waste fuel, as appropriate.

Regarding the commenter’s points related to meaningful 

heating value of dried manure, the fact that dried manure may 

have a greater Btu value than bagasse is not directly on point. 

To demonstrate that a NHSM has meaningful heating value when 

used as a fuel, a facility does not compare relative Btu/lb of 

the NHSM against other traditional fuels, which themselves have 

 

121 76 FR 15482.
Page 290 of 319

a wide range of heating values. Rather, consistent with other 

EPA rulemakings, we have established 5,000 Btu/lb as a benchmark 

for demonstrating that a NHSM has meaningful heating value. 

Thus, to meet the meaningful heating value legitimacy criterion, 

the material would need to meet an “as fired” heating value of 

5,000 Btu/lb, or if lower than 5,000 Btu/lb, as fired, a person 

would need to demonstrate that the ERU can cost-effectively 

recover meaningful energy from the NHSM used as a fuel.122 We 

also note that the EPA did not reopen the meaningful heating 

value for fuels, as codified in 40 CFR part 241.3(d)(1)(ii), in 

the December 23, 2011, proposed rule. Thus, in order to meet 

this criterion, the dried manure would need to meet an “as 

fired” heating value of 5,000 Btu/lb, or if lower than 5,000 

Btu/lb, the facility would need to demonstrate that the ERU can 

cost-effectively recover meaningful energy from use of manure as 

a fuel.

Regarding the commenter’s statement regarding contracts 

between livestock and poultry producers and combustors, first we 

would note that no information has been provided to indicate who 

has entered such contracts or how many such contracts there are 

to consider this factor. However, as we have stated elsewhere in 

this preamble, contractual arrangements can be used as evidence 

that the material is managed as a valuable commodity and that 

 

122 See 76 FR 15541. 
Page 291 of 319

discard is not occurring when a material is transferred beyond 

the control of the generator. However, the fact that there is a 

contractual relationship by itself is not dispositive that a 

material is not a waste, as there are contracts between parties 

to remove and dispose of wastes.

We also believe that the commenter’s statements that the 

concentrated levels of contaminants is no different than what 

occurs in the production of “byproducts of ethanol natural 

fermentation processes” is not supported by any information or

data. That is, other than the general statement, the commenter 

has not provided contaminant data, for either animal manure or 

byproducts of ethanol natural fermentation processes, for the 

agency to analyze and compare. 

Thus, we have determined based on the lack of any 

information or data that animal manure should not be listed as a 

categorical non-waste fuel in part 241.4(a). 

Comment: In the event that the agency does not list animal 

manure as a categorical non-waste fuel, the EPA could 

alternatively decide that processing of animal manure by drying, 

constitutes “sufficient processing,” such that previously 

discarded manure could be considered recovered for energy 

recovery, just like scrap tires could be processed and burned as 

a non-waste.

Response: In the December 23, 2011 proposal, the agency did 
Page 292 of 319

not solicit comment on the definition of “processing,” as 

codified in 40 CFR part 241.2. Thus, this comment is beyond the 

scope of the rulemaking and will not be addressed in today’s 

final action.

d. Other Materials for Which Additional Information was Not 

Requested

In the December 2011 proposal, the agency solicited comment 

on a focused list of NHSMs and, in particular, whether these 

specific NHSMs would be appropriately enumerated in the 

categorical list of non-waste fuels that the agency was 

proposing in 40 CFR 241.4(a). Specifically, the agency invited 

comment and additional information regarding potential 

categorical non-waste determinations for resinated wood, scrap 

tires managed pursuant to established tire collection programs, 

pulp and paper sludges, coal refuse recovered from legacy piles, 

and manure. 

Although comment was requested only for these specific 

materials, the agency received comments that many other NHSMs be 

listed as categorical non-wastes for which it did not request 

additional information as a part of this rulemaking. As we have 

discussed elsewhere in today’s preamble, we will not be 

responding to such comments and issues that are beyond the scope 

of today’s narrow rulemaking. We would also note that since the 

agency did not specifically solicit comments on these additional 
Page 293 of 319

materials and whether they should be categorically listed in 40 

CFR 241.4(a), the agency could not make final decisions without 

first going through notice and comment rulemaking. 

However, we would like to note in particular three 

additional NHSMs that, based on the information provided to the 

agency on the proposed rule, may be potential candidates for 

future categorical non-waste determinations: (1) construction 

and demolition materials processed pursuant to best management 

practices and produced and managed under the oversight of a 

comprehensive collection system or contractual arrangement; (2) 

paper recycling residuals (including old corrugated cardboard 

(OCC rejects)); and (3) creosote-treated wood. For these three 

NHSMs, the agency received new information, both in comments and 

during meetings with concerned stakeholders during the 

rulemaking process, 123 which the EPA believes would be useful in 

making determinations regarding the listing of these materials 

as categorical non-waste fuels. However, the agency has only 

preliminarily reviewed this material, as well as in some cases, 

 

123 In addition to comments received during the comment period, additional 

information was provided to the Agency during the following meetings: (1) 

April 4, 2012 meeting with Biomass Power Association, California Biomass 

Energy Alliance, and the Construction Materials Recycling Association to 

discuss C&D materials processed pursuant to best management practices; (2) 

March 22, 2012 meeting with AF&PA member companies to discuss several NHSMs, 

including OCC rejects; and (3) March 23, 2012 meeting with the Treated Wood 

Council and member companies to discuss creosote-treated wood. Information 

regarding these materials, as well as documents provided during the meeting, 

is included in the docket for today’s rule. 
Page 294 of 319

additional information is expected.124 Petitioners believing that 

the agency should make such a determination should utilize the 

rulemaking process being finalized in 40 CFR 241.4(b), which 

provides a mechanism for the regulated community to list 

additional NHSMs to the list of categorical non-waste fuels in 

40 CFR 241.4(a). 

Regardless of whether a future categorical non-waste 

determination is appropriate for these three non-hazardous 

secondary materials, we note that there are other pathways 

available today for a facility (or facilities) to determine 

whether these or other NHSMs are non-waste fuels. For example, a 

facility that wants to burn these materials within the control 

of the generator need only make a self-determination and 

document that these materials meet the legitimacy criteria 

pursuant to 40 CFR 241.3(b)(1). In addition, if these same 

materials are transferred off-site to a party that is not within 

the control of the generator, the generator or the combustor 

could petition the agency for a non-waste determination pursuant 

to 40 CFR 241.3(c). Finally, if a NHSM is recovered from the 

discard environment, but is processed into a product fuel, the 

 

124 For example, the Association of American Railroads has indicated in 

previous discussions with EPA that it would be providing additional HAP data 

in an effort to demonstrate that creosote-treated can meet the contaminant 

legitimacy criterion and should not be considered a solid waste when used as 

a fuel. See the November 2, 2011 letter from James R. Berlow to Michael Rush 

for background on these discussions. A copy of this letter has been placed in 

the docket for today’s rule. 
Page 295 of 319

combustor need only make a self-determination and document that 

such material is a non-waste fuel by being sufficiently 

processed and meeting the legitimacy criteria pursuant to 40 CFR 

241.3(b)(4). To the extent that the regulated community has 

material- or case-specific questions or issues, the agency will 

consider issuing clarification letters, if appropriate, as it 

has historically done in the past.125

Although we are specifically noting in today’s preamble 

three NHSMs as possible candidates for future categorical nonwaste determinations, we emphasize that the rulemaking petition 

process codified in 40 CFR 241.4(b) is not limited to these 

three NHSMs.

6. Streamlining of the 40 CFR 241.3(c) Non-Waste Determination 

Petition Process

In the proposed rule, the EPA asked for comments on 

streamlining or other improvements to the existing provision for 

non-waste determinations codified at 40 CFR 241.3(c). 

The agency requested comment on whether the EPA’s grant of 

the petition should apply as of the date that the petition was 

submitted to the agency.126 The agency also requested additional 

comment on whether any other changes could be made to the non-

 

125 Copies of clarification letters that have been previously issued by the 

Agency regarding the March 2011 NHSM rule can be found at 

www.epa.gov/epawaste/nonhaz/define/index.htm#gc.

126 See 76 FR 80473.
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waste determination petition in order to streamline the process, 

while at the same time provide the EPA with the opportunity to 

ensure that such NHSMs are not being discarded. For example, the 

EPA requested comment on whether public comment should be sought 

on each individual petition.127 

Comment: Concerning the request for comment regarding when 

a petition determination would apply, the agency received 

several comments. Specifically, the agency requested comment on 

whether the EPA’s grant of the petition should apply as of the 

date that the petition was submitted to the agency. Commenters 

agreed that a non-waste determination under 40 CFR 241.3(c) 

should be retroactively applied to the date the petition was 

submitted.

Commenters were concerned about the timeliness of the EPA’s 

decision on these determinations and on the uncertainty 

surrounding the usage of the NHSMs while a non-waste 

determination petition is pending. The commenters argue that if 

a NHSM is determined to be non-waste, the combusted NHSM in 

question was also non-waste prior to the determination. 

Response: The agency understands the interests of 

petitioners awaiting an agency decision on the status of 

materials, while a 40 CFR 241.3(c) petition is being considered. 

In order to lessen the uncertainty surrounding the regulatory 

 

127 See 76 FR 80474.
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status of a particular material, the agency will utilize the 

date the petition was submitted as the date that the combusted 

materials will be considered a non-waste if the agency grants 

the petition. 

Comment: Many commenters indicated concern that the 

petition process could take excessive time for the agency to 

reach a decision. They requested self-imposed timeframes for the 

EPA’s granting/denying requests and a shorter length of time for 

the notices to be open for public comment (or omit it 

altogether). The combustors stated they need quick decisions in 

order to comply with the CAA regulations and to make efficient 

business decisions. 

Response: The agency considered the commenters suggestion, but 

decided not to impose a deadline on its decision because there 

are many factors beyond its control, including how long it takes 

for the petitioner to submit a complete petition to EPA for 

evaluation. We would note, however, that even though the NHSM 

rule will become effective on [Insert 60 days after promulgation 

in the Federal Register], for all practical purposes, existing 

facilities that currently burn NHSMs from off-site sources will 

have a substantial amount of time to submit and have the EPA 

process a non-waste determination petition before having to 

comply with the CAA emission standards, as the compliance date 

for existing CISWI sources subject to CAA 129 standards is 5 
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years after the date of publication of the CISWI final rule or 3 

years after the state plan is approved, whichever happens 

earlier and [Insert 3 years after promulgation in the Federal 

Register] to comply with the Boiler MACT rule.128,129 Thus, we 

believe that there will be more than adequate time for persons 

to determine whether or not a NHSM sent to a combustion unit not 

under the control of the generator has not been discarded and 

meets the legitimacy criteria, prepare and submit a non-waste 

determination petition to the EPA, have the EPA process the 

petition, including soliciting comment on the EPA’s proposed 

determination, and make a final decision. 

In regard to the comment on reducing the time the petition 

application is open for public comment, the agency decided that 

the comment period shall remain at 30 days but the regulatory 

text is changed from “at least 30 days" to “30 days” in order to 

promote clarity, while affording an opportunity for public 

comment.

Comment: One commenter strongly encouraged the agency to 

develop and deploy an on-line form to identify materials for 

non-waste determinations. Commenters also noted that the EPA 

should provide more detailed information about how the 

 

128 We recognize that new sources that are coming online that will have to 

comply with these rules much sooner than do existing sources. As such, the 

Agency will consider prioritizing the processing of non-waste petitions it 

has received from new sources as appropriate.

129 Note that the compliance date for the Area Source Boiler Rule is March 21, 

2014. 
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determinations are made (particularly for the comparable 

contaminant determinations).

Response: The agency will consider the development of a 

form to identify the specific information needed to determine 

whether a NHSM meets the legitimacy criteria and other 

provisions. If the agency develops such a form, it would be made 

available on the NHSM website. Please note that traditional fuel 

data (including tables for traditional contaminants) are 

available to the public, which they may find useful in assessing 

the contaminant legitimacy criteria. Refer to those tables in 

“Contaminant Concentrations in Traditional Fuels: Tables for 

Comparison” currently posted on the NHSM web site at 

http://www.epa.gov/osw/nonhaz/define/index.htm. That document 

will aid in comparing the concentration of contaminants in their 

NHSMs to concentration of contaminants in traditional fuels. In 

addition, rule clarification letters and petition findings are 

also posted on the website when finalized. 

Comment: A commenter suggested that the non-waste petition 

process should allow for “balancing” of legitimacy criteria 

similar to that included for categorical determinations in 40 

CFR part 241.4. 

Response: Under 40 CFR 241.4 of the proposed regulation, 

the EPA can balance the legitimacy criteria with other relevant 

factors in making categorical non-waste determinations. As the 
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commenter points out, we have not discussed the applicability 

for similar balancing under 40 CFR 241.3 non-waste determination 

petitions. The EPA distinguished between 40 CFR 241.3 and 40 CFR 

241.4 because in the latter, the EPA makes the determination 

based on its review and analysis of industry-wide data and other 

factors, as opposed to a specific site. However, the EPA 

recognizes the points the commenter raises and will consider 

whether such modifications may be appropriate.

Comment: Several commenters were interested in features 

that streamline and add flexibility to the administrative 

petition process, particularly in the situation where a petition 

can apply to multiple combustors. 

One commenter noted that any interested person – including 

forest owners – should be able to initiate the petition process, 

not just combustors. The petitions should be allowed for entire 

classes of a NHSM rather than requiring a case-by-case analysis. 

These clarifications will encourage all members in the biomass 

supply chain to promote their products and co-products as clean, 

renewable fuels and promote the development of new markets for 

biomass materials. Other commenters also stressed the need for 

the EPA to clarify that the petition can apply to more than one 

combustor so that redundant petitions do not need to be filed in 

every region. 
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A commenter also stated that the benefits from petitions 

could be achieved more efficiently if the regulatory language 

was changed to allow for nation-wide petitions under 40 CFR 

241.3(c) for classes of combustion units rather than requiring 

separate petitions for each EPA region. 

Response: The agency agrees with the commenters that the 

process should accommodate for petition applications from third 

party producers of a NHSM that can be used as a non-waste NHSM 

fuel at many combustion units instead of just accepting 

petitions from individual combustors or combustors within the 

control of one EPA region. This can make for a more streamlined 

and efficient process. Therefore, the regulatory provision at 40 

CFR 241.3(c) has been modified to allow for the petition to be 

sent to the Assistant Administrator for the OSWER instead of 

each Regional Administrator if the petition covers more than one 

EPA Region. This is at the option of the petitioner. The 

Assistant Administrator for the OSWER would be responsible for 

the EPA’s administrative process in order to finalize the 

petition decision under 40 CFR 241.3(c) and the regulatory 

language has been modified accordingly.

Finally, as noted in the 2011 NHSM final rulemaking, 

states, or private entities, can submit non-waste determination 

petitions to the EPA on behalf of petitioners. They can petition 

for a single combustor or a class of combustors (e.g., a 
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specific usage of a non-hazardous secondary material in a 

particular state). Therefore, in regard to the comment on 

nationwide petitions for classes of combustion units, the 

petition process accommodates for these classes of combustion 

units. This assumes that the petition identifies all of the 

specific NHSMs that the classes of combustion units use as fuel 

(that are applicable to a 40 CFR 241.3(c) petition) and gives 

the information necessary to meet the legitimacy criteria and 

other requirements.

Note that if a petition covers multiple facilities in a 

single region, the petition should be sent to the Regional 

Administrator for that Region, not to the Assistant 

Administrator for the OSWER. 

Comment: Several commenters argued that the 40 CFR 241.3(c) 

petitions should not require public comment for each individual 

petition. 

One commenter stated that “the administrative petition 

process could be further streamlined by not seeking public 

comment on every individual petition. By filing an 

administrative petition, a petitioner is not seeking to change 

the EPA’s regulatory program or create new legal rights or 

obligations. Instead, the administrative petition process 

provides an opportunity for a petitioner to obtain in advance 

[A]gency concurrence, based on sound science, with respect to 
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the classification of a particular feedstock under existing 

regulations. In this respect, the administrative petition 

process differs from the categorical non-waste 

determination...where EPA makes changes to the regulatory status 

of certain non-hazardous secondary materials that are reflected 

in the Code of Federal Regulations. Because the public – through 

this rulemaking process – has an opportunity to provide input on 

EPA’s regulations, there is no need to provide a second 

opportunity for public comment when those regulations are 

applied by the EPA in specific contexts through the 

administrative petition process.”

In addition, other commenters indicated that public notice 

and comment is not necessary, since the NHSM rulemaking process 

has already taken comment on the methodology, in addition to 

other rationale. In particular, one commenter stated, 

“Streamlining could be further facilitated by recognizing that 

solicitation of public comment on each individual application 

would be redundant and unnecessary given the public’s ample 

opportunity during this rulemaking to comment on the evaluation 

criteria that will govern non-waste determination petitions.” 

Another commenter stated, “The reason for public participation 

in the hazardous waste petition process is that the materials 

subject to the petition are to be removed from the hazardous 

waste regulatory program. In the NHSM world, the secondary 
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materials subject to the petition are merely obtaining clarity 

about regulatory status – they are not seeking a change in 

regulatory status. Therefore, the need for the full public 

participation process is not necessary or warranted.”

Response: Although industry commenters argued that public 

participation is unnecessary, the EPA still believes that public 

participation is an important part of a transparent decision 

making process and values how it increases transparency. In the 

final rule, we will retain the public participation requirement 

in order to promote public awareness. 

7. Revised Introductory Text for 40 CFR 241.3(a)

As part of its discussion clarifying the non-waste 

determination petition processes, the EPA noted that it had 

examined a number of specific NHSMs and decided which were to be 

considered solid wastes based on the record available at the 

time the March 2011 final rule was issued.130 The rule itself had 

stated at 40 CFR 241.3(a) that secondary materials were solid 

wastes except for those described in section 241.3(b). 

Essentially, section 241.3(b) is the operative section that 

states what materials are not wastes. The purpose of the nonwaste determination petition process in section 241.3(c) and the 

new proposed petition process in section 241.4 is to allow 

various parties the opportunity to provide information and data 

 

130 See 76 FR 80473. 
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so that the EPA could decide what other NHSMs are not solid 

wastes. The preamble stated that the agency proposed to amend 

section 241.3(a) to state that such secondary materials are 

“presumed to be” solid wastes except for those described in 

section 241.3(b) in order to better reflect the rulemaking 

record. 

Comment: No comment supported inclusion of the “presumed to 

be” language in the rule. 

Most of the comments on the language argue that it means 

that the EPA continues to improperly determine that certain 

NHSMs are presumptively wastes. Comments generally argue that 

the “presumed to be” language shows that the EPA, in spite of 

statements to the contrary, is continuing to make an 

inappropriate determination that NHSMs transferred to other 

parties are presumptively wastes until a combustor proves 

otherwise. According to comments, the use of the “presumed to 

be” language is a clear statement that the EPA is making the 

presumption. The addition of these words does not change the 

fact that, under the EPA’s regulatory framework, NHSMs are

wastes until proven otherwise. 

Several comments, in fact, argued that to address the legal 

flaws in the proposal, the EPA should reverse the presumption 

and presume that NHSMs burned for energy recovery or used as an 
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ingredient is not for the purpose of disposal and, therefore, is 

not a waste. 

Response: The EPA is not addressing in this rulemaking the 

comment that the agency has inappropriately made presumptions 

about whether materials are wastes. This issue has not been 

reopened. Instead, the agency has only opened very specific 

issues on particular wastes. 

In the December 2011, proposal at 76 FR 80473, the EPA 

referred to the March 2011 preamble in which the agency stated 

that it has not “arbitrarily determined that secondary materials 

transferred between companies are wastes. Instead, the EPA has 

evaluated whether certain categories of materials are discarded 

or not. The Agency has not adopted the extremes of saying that 

all burning of secondary material, regardless of ultimate use, 

is waste treatment or that any secondary material that is 

recycled for legitimate fuel value is a commodity and not a 

waste. Wastes may have value, but are still wastes.” 76 FR 

15471. Further, the agency stated that it “has examined a number 

of specific materials, recycled within the control of the 

generator and transferred to a third party for recycling, and 

determined whether they would be appropriately placed within the 

waste or non-waste categories.” Id. The EPA went on to examine a 

number of different categories of NHSMs used as fuels and 

ingredients that was summarized in the Federal Register (76 FR 
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15477-15520). The EPA cannot “reverse” a presumption that it 

never made to declare that materials burned for energy recovery 

are presumptively non-wastes. Further, it would be entirely 

improper for the agency to do so. The EPA has evaluated specific 

groups of materials as to their waste status, while the comments 

regarding reversal of a purported presumption have only 

presented arguments “in broad abstraction, providing little 

detail about the many processes throughout the industry that 

generate residual material” that could be subject to this rule. 

Association of Battery Recyclers v. EPA, 208 F.3d 1047, 1056.131

Accordingly, the agency stands on its March 2011 rulemaking 

record for the issues discussed in these comments. 

Comment: Comments objected that the change in word choice 

that materials are “presumed to be” solid wastes from the 

statement that that materials “are” solid wastes (except as 

otherwise provided in the regulation) still puts the burden to 

prove material is not a waste on persons who use NHSMs in 

combustion units. One comment, in particular, noted that there 

would be no practical effect of the new language even though it 

is viewed by the EPA as an “optically less drastic stance.” That 

is, there would be no real leeway for a party in an enforcement 

 

131 Note how the April 4, 2012, letter from Timothy G. Hunt to James Berlow (a 

copy of which is in the docket for today’s rule), provided specific 

information on pulp and paper sludge where the EPA added a categorical 

determination based on specific information provided by industry. 
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proceeding to counter the EPA’s prosecution based on the fact 

that the secondary material in question is only “presumed to be” 

a waste, rather than the material “is” a waste. 

Response: The EPA has decided not to retain the “presumed 

to be” language, since it is unnecessary and does not actually 

reflect the rulemaking record. No comment argued in favor of it. 

In addition, there is no need to temper the existing language 

stating that a material is a solid waste if it does not fall 

within the section 241.3(b) categories or the non-waste 

determination processes. As noted in the previous response to 

comments regarding the agency’s “presumption” of the waste 

status of materials, the agency stands on its March 2011 

rulemaking record. 

E. Cost and Benefits of the Final Rule 

The RCRA aspects of this rule do not directly invoke any 

costs (excluding minor administrative burden/cost), or benefits. 

Any RCRA related costs to the regulated community, and 

corresponding benefits to human health and the environment, have 

been considered as part of the CISWI action, and the 

corresponding CISWI and Boiler MACT (area source and major 

source) final rules. As such, the agency has not prepared a 

separate cost-benefit assessment in support of this part of the 

final rule. Consequently, any potential costs or benefits, 

including impacts to small entities, indirectly associated with 
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the RCRA aspects of this rule are addressed in the corresponding 

impact assessment prepared in support of the CISWI part of this 

action.

IV. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and 

Executive Order 13563: Improving Regulation and Regulatory 

Review

Under Executive Order 12866 (58 FR 51735, October 4, 1993), 

this action is a “significant regulatory action” because it may 

raise novel legal or policy issues. Accordingly, the EPA 

submitted this action to OMB for review under Executive Order 

12866 and 13563 (76 FR 3821, January 21, 2011). Any changes made 

in response to OMB recommendations have been documented in the 

docket for this action. 

In addition, the EPA prepared an update to the RIA of the 

potential costs and benefits associated with this action. The 

RIA available in the docket describes in detail the empirical 

basis for the EPA’s assumptions and characterizes the various 

sources of uncertainties affecting the estimates below and a 

memo documents the updates since the RIA was prepared. Table 9 

of this preamble shows the results of the cost and benefits 

analysis for these final rules.

Table 9. Summary of the Monetized Benefits, Social Costs and Net 

Benefits for the Final CISWI NSPS and EG In 2015 (Millions of 

2008$)1
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3 percent Discount 

Rate

7 percent Discount 

Rate

Total Monetized 

Benefits2 $420 to $1000 $390 to $940

Total Social 

Costs3 $270 $270

Net Benefits $150 to $670 $150 to $770

Non-monetized 

Benefits

Health effects from exposure to HAP 780 

tons of HCl, 2.6 tons of lead, 1.8 tons of 

Cd, 690 pounds of Hg, and 58 grams of 

dioxins/furans)

Health effects from exposure to criteria 

pollutants (20,000 tons of CO, 6,300 tons of 

SO2, 5,400 tons of NO2, and secondary 

formation of ozone) 

Ecosystem effects 

Visibility impairment 

1 All estimates are for the implementation year (2015) and are 

rounded to two significant figures. These results reflect the 

lowest cost disposal assumption.

2 The total monetized benefits reflect the human health benefits 

associated with reducing exposure to PM2.5 through reductions of 

PM2.5 precursors such as directly emitted particles, SO2, and 

NOx. It is important to note that the monetized benefits 

include many but not all health effects associated with PM2.5

exposure. Monetized benefits are shown as a range from Pope, et 

al. (2002) to Laden, et al. (2006). These models assume that 

all fine particles, regardless of their chemical composition, 

are equally potent in causing premature mortality because there 

is no clear scientific evidence that would support the 

development of differential effects estimates by particle type. 

These estimates include the energy disbenefits valued at $3.8 

million (using the 3 percent discount rate), which do not 

change the rounded totals. CO2-related disbenefits were 

calculated using the “social cost of carbon”, which is 

discussed further in the RIA.

3The methodology used to estimate social costs for 1 year in the 

multimarket model using surplus changes results in the same 

social costs for both discount rates.

B. Paperwork Reduction Act
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This action does not require any new information collection 

burden. This action is believed to result in no additional 

impact on the aggregate information collection estimate of 

project cost and hour burden made and approved by OMB. Due to 

changes in the CISWI inventory and monitoring requirements of 

the CISWI rule, the information collection estimate of project 

cost and hour burden have been revised. Therefore, only the 

CISWI ICR has been revised. The OMB control numbers for the 

EPA’s regulations in 40 CFR are listed in 40 CFR part 9.

However, OMB has previously approved the information 

collection requirements contained in the existing CISWI and 

NHSM132 regulations (40 CFR part 60, subparts CCCC and DDDD, and 

40 CFR part 241) under the provisions of the Paperwork Reduction 

Act, 44 U.S.C. 3501, et seq., and has been assigned EPA ICR 

number 2384.04 for subpart CCCC, 40 CFR part 60, EPA ICR number 

2385.04 for subpart DDDD, 40 CFR part 60, and EPA ICR number 

2382.04 for 40 CFR part 241. 

C. Regulatory Flexibility Act

The RFA generally requires an agency to prepare a 

regulatory flexibility analysis of any rule subject to notice 

and comment rulemaking requirements under the APA or any other 

statute unless the agency certifies that the rule will not have 

 

132 Identification of Non-Hazardous Secondary Materials That Are Solid Waste, Final 

Rule. March 11, 2011.
Page 312 of 319

a SISNOSE. Small entities include small businesses, small 

organizations and small governmental jurisdictions. 

For purposes of assessing the impacts of today’s rule on 

small entities, small entity is defined as: (1) a small business 

as defined by the SBA’s regulations at 13 CFR 121.201; (2) a 

small governmental jurisdiction that is a government of a city, 

county, town, school district or special district with a 

population of less than 50,000; or (3) a small organization that 

is any not-for-profit enterprise that is independently owned and 

operated and is not dominant in its field.

After considering the economic impacts of today’s final 

rule on small entities, I certify that this action will not have 

a SISNOSE. This final rule will not impose any new requirements 

on any entities because it does not impose any additional 

regulatory requirements relative to those specified in the March 

2011 final CISWI and NHSM rules. The March 2011 final CISWI and 

NHSM rules were both certified as not having a SISNOSE. In this 

final action, there are three fewer small entities in the CISWI 

than in the March 2011 final CISWI rule, as discussed in the 

“Regulatory Impact Results for the Reconsideration Final for 

Standards of Performance for New Stationary Sources and Emission 

Guidelines for Existing Sources: Commercial and Industrial Solid 

Waste Incineration Units” memorandum in the CISWI docket. 

D. Unfunded Mandates Reform Act
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This action does not contain a federal mandate that may 

result in expenditures of $100 million or more for state, local 

and tribal governments, in the aggregate or the private sector 

in any one year. This rule finalizes amendments to the final 

CISWI rule provisions and technical clarifications to the final 

NHSM rule. Thus, this rule is not subject to the requirements of 

sections 202 or 205 of UMRA. However, the March 2011 final CISWI 

rule contains a federal mandate that may result in expenditures 

of $100 million or more for state, local and tribal governments, 

in the aggregate, or the private sector in any 1 year. 

Accordingly, we have prepared under section 202 of the UMRA a 

written statement, which is summarized in the preamble to the 

final CISWI rule (76 FR 15747). 

This rule is also not subject to the requirements of

section 203 of UMRA because it contains no regulatory 

requirements that might significantly or uniquely affect small 

governments. 

E. Executive Order 13132: Federalism

This action does not have federalism implications. It will 

not have substantial direct effects on the states, on the 

relationship between the national government and the states, or 

on the distribution of power and responsibilities among the 

various levels of government, as specified in Executive Order 

13132. This final rule will not impose direct compliance costs 
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on state or local governments and will not preempt state law. 

Thus, Executive Order 13132 does not apply to this action.

F. Executive Order 13175: Consultation and Coordination with 

Indian Tribal Governments

This action does not have tribal implications, as specified 

in Executive Order 13175, (65 FR 67249, November 9, 2000). The 

EPA is not aware of any CISWI in Indian country or owned or 

operated by Indian tribal governments. The CISWI aspects of this 

rule may, however, invoke minor indirect tribal implications to 

the extent that entities generating solid wastes on tribal lands 

could be affected. However, any indirect NHSM impacts that may 

occur as a result of the CISWI action are expected to be 

negligible due to the very limited focus of the CISWI part or 

this rule. Thus, Executive Order 13175 does not apply to this 

action.

G. Executive Order 13045: Protection of Children from 

Environmental Health Risks and Safety Risks

The EPA interprets Executive Order 13045 (62 FR 19885, 

April 23, 1997) as applying to those regulatory actions that 

concern health or safety risks, such that the analysis required 

under section 5-501 of the Executive Order has the potential to 

influence the regulation. This action is not subject to 

Executive Order 13045 because it is based solely on technology 

performance and technical corrections. 
Page 315 of 319

H. Executive Order 13211: Actions Concerning Regulations That 

Significantly Affect Energy Supply, Distribution, or Use

This action is not subject to Executive Order 13211 (66 FR 

28355, May 22, 2001), because it is not a significant regulatory 

action under Executive Order 12866.

I. National Technology Transfer and Advancement Act

Section 12(d) of the NTTAA of 1995, Public Law No. 104-113, 

12(d) (15 U.S.C. 272 note) directs the EPA to use VCS in its 

regulatory activities, unless to do so would be inconsistent 

with applicable law or otherwise impractical. Voluntary 

consensus standards are technical standards (e.g., materials 

specifications, test methods, sampling procedures and business 

practices) that are developed or adopted by VCS bodies. The 

NTTAA directs the EPA to provide Congress, through OMB, 

explanations when the agency decides not use available and 

applicable VCS.

This action does not involve any revisions to the technical

standards or test methods required in the final CISWI rule. 

Therefore, the EPA did not reconsider the use of any VCS.

J. Executive Order 12898: Federal Actions to Address 

Environmental Justice in Minority Populations and Low-Income 

Populations

Executive Order 12898 (59 FR 7629, February 16, 1994) 

establishes federal executive policy on EJ. Its main provision 
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directs federal agencies, to the greatest extent practicable and 

permitted by law, to make EJ part of their mission by 

identifying and addressing, as appropriate, disproportionately 

high and adverse human health or environmental effects of their 

programs, policies and activities on minority populations and 

low-income populations in the United States.

The EPA has determined that this final rule will not have 

disproportionately high and adverse human health or 

environmental effects on minority or low-income populations 

because it increases the level of environmental protection for 

all affected populations without having any disproportionately

high and adverse human health or environmental effects on any 

population, including any minority or low-income population. The 

amendments do not relax the control measures on sources 

regulated by the CISWI rule, and, therefore, will not cause 

emissions increases from these sources. The March 2011 final 

CISWI rule will reduce emissions of all the listed HAP emitted 

from this source. Furthermore, the targeted revisions finalized 

in the NHSM section of this rule are designed to improve the 

management of these materials, thereby helping to further ensure 

against any disproportionately high and adverse human health or 

environmental effects on minority or low-income populations.

K. Congressional Review Act
Page 317 of 319

The Congressional Review Act, 5 U.S.C. 801 et seq., as 

added by the SBREF of 1996, generally provides that before a 

rule may take effect, the agency promulgating the rule must 

submit a rule report, which includes a copy of the rule, to each 

House of the Congress and to the Comptroller General of the 

United States. The EPA will submit a report containing this rule 

and other required information to the U.S. Senate, the U.S. 

House of Representatives and the Comptroller General of the 

United States prior to publication of the rule in the Federal 

Register. A major rule cannot take effect until 60 days after it 

is published in the Federal Register. This action is not a 

“major rule” as defined by 5 U.S.C. 804(2). This rule will be 

effective [INSERT THE DATE OF PUBLICATION OF THE FINAL RULE IN 

THE FEDERAL REGISTER].
Standards of Performance for New Stationary Sources and Emission 

Guidelines for Existing Sources:

Commercial and Industrial Solid Waste Incineration Units

Page 318 of 319

List of Subjects 40 CFR Part 60

Environmental protection, Administrative practice and 

procedure, Air pollution control, Hazardous substances.

40 CFR Part 241

Environmental protection, air pollution control, waste 

treatment and disposal. 

Dated:

Lisa P. Jackson,

Administrator.
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