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July 15, 2011

Via Electronic Transmission: combustionsurvey@erg.com; shrager.brian@epa.gov; 

jones.toni@epa.gov

EPA Docket ID. No. EPA-HQ-OAR-2002-0058

EPA Docket ID. No. EPA-HQ-OAR-2003-0119

Ms. Toni Jones & Mr. Brian Shrager

Sector Policies and Programs Division

Office of Air Quality Planning and Standards

U.S. Environmental Protection Agency

Research Triangle Park, NC 27711

Dear Ms. Jones and Mr. Shrager:

Waste Management (WM) is pleased to provide additional data and information to inform the 

Agency’s reconsideration of the “National Emission Standards for Hazardous Air Pollutants for 

Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters” 

(hereinafter the “Boiler Rule”) and “Standards of Performance for New Sources and Emission 

Guidelines for Existing Sources: Commercial and Industrial Solid Waste Incineration Units” 

(hereinafter the “CISWI Rule”). As North America’s leading provider of integrated 

environmental solutions, WM is uniquely interested in ensuring that the Agency’s final CISWI 

Rule and Boiler Rule upon reconsideration reflect and support ongoing and newly evolving 

efforts to reduce, reuse and manage waste, while recovering valuable resources and producing 

clean renewable energy. In addition, these rules must not unfairly and without notice, change 

longstanding regulatory determinations and control standards that currently apply to landfill 

gas.

WM has been a constant advocate of landfill gas as a renewable alternative fuel. WM operates 

131 landfill gas-to-energy projects that produce enough renewable energy to power nearly half 

a million homes and replace use of about 2.4 million tons of coal per year. These projects offset 

criteria pollutants and hazardous air pollutants associated with coal use and also offset nearly 3 

million tons of CO2e emissions each year. While most of our renewable energy projects involve 

combusting landfill gas in engines or turbines to produce electricity, about twenty percent of 

our projects involve treating and conveying landfill gas to third parties to use as fuel in their 

facility boilers. Some of our landfill gas customers include BMW, DuPont, Dow, GM, Ford, the 

University of New Hampshire and NASA Goddard Spaceflight Center. These organizations have 

chosen to utilize landfill gas as a viable replacement for fossil fuel, and as a key element of their 

corporate sustainability goals. Furthermore, investment in these projects has been strongly 
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encouraged by Congress and EPA’s Landfill Methane Outreach Program (LMOP). Failure to 

harmonize the Boiler Rule and CISWI Rule standards with national renewable energy and 

greenhouse gas reduction goals will undermine significant sustainability investments by private 

companies, local governments, and federal agencies. In addition, the imposition of new and 

unreasonable regulatory burdens upon the combustion of landfill gas will conflict with existing 

Clean Air Act regulations governing landfill gas control and use as a renewable fuel, including 

the Standards of Performance for Municipal Solid Waste Landfills, 40 C.F.R. Part 60, Subpart 

WWW (the “Landfill NSPS”) and the National Emission Standards for Hazardous Air Pollutants: 

Municipal Solid Waste Landfills, 40 C.F.R Part 63, Subpart AAAA (the “Landfill MACT”).

EPA Must Clarify that the CISWI Rule Does Not Apply to Combustion of Landfill 

Gas

First and foremost, EPA must clarify that the CISWI Rule does not apply to the combustion of 

landfill gas, either when combusted for control (as in an enclosed flare) or combusted as a fuel 

(as in a boiler). WM submitted a petition for reconsideration of the final CISWI Rule, which we 

have appended as Attachment A. WM’s petition focused on EPA’s removal of the definition of 

“contained gaseous material” from the final CISWI Rule, which represents a significant shift 

away from EPA’s established interpretation of the scope of section 129 of the CAA, as it relates 

to the definition of “solid waste” under the Resource Conservation and Recovery Act (RCRA). 

EPA’s statements in a related rulemaking record further indicate that EPA’s final CISWI rule 

departs significantly from EPA’s established interpretation of section 129 of the CAA. 

Specifically, in its Response to Comments for the Identification of Non-Hazardous Secondary 

Materials That Are Solid Waste Rule, published at 76 Fed. Reg. 15456 (March 21, 2011) (NHSM 

Rule), EPA cast significant doubt on the continued vitality of its past interpretation of 

“contained gaseous materials,” and suggested the combustion of air emissions for pollution 

control may constitute the combustion of solid waste subject to the CISWI Rule. Further, EPA 

stated that landfill gas may constitute “solid waste” simply because landfill gas is extracted 

from a waste mass, and if used as fuel would be subject to a demonstration of legitimacy under 

the NHSM Rule. 

Taken together, these two Agency actions signal a significant shift in policy and regulatory 

precedent and were made without any prior notice to regulated entities, and without

opportunity for comment. For over twenty years, EPA has developed a comprehensive 

regulatory structure to govern the collection, control and treatment of landfill gas under the 

Clean Air Act —a structure based on the correct determination that landfill gas is not a solid 

waste under RCRA. EPA’s deletion of the definition of contained gaseous material and 

statements in the NHSM rulemaking record threaten to undercut the existing regulatory 

scheme established under the CAA by potentially subjecting landfill gas combustion to the 

CISWI Rule. Regulation of LFG as a solid waste also threatens to undermine the market for LFG 

as a fuel, in direct contradiction to the stated goals of EPA’s Landfill Methane Outreach Program 

and the administration’s broader goals to encourage domestic, renewable energy sources.
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It is clear from a review of the CISWI rulemaking record that the Agency did not contemplate 

the possibility that landfill gas combustion units may be subject to CISWI. EPA’s evaluation of 

regulatory impacts did not identify massive costs associated with application of the rule to 

thousands of landfill gas combustion sources. Regulation of landfill gas under section 129 of 

the CAA would dramatically affect the cost of capture and control of landfill gas. As an initial 

matter, WM anticipates that current third party users of landfill gas would discontinue using 

landfill gas when faced with strict emission limits. Without an end market for the sale or 

transfer of gas, WM and other landfill owners /operators will be left with greater quantities of 

landfill gas to control. For example, landfill gas flares (which are approved pollution control 

devices under the Landfill NSPS and Landfill MACT) would need to be replaced with thermal 

oxidizers to meet section 129 emission limits. For WM alone, we estimate our capital costs for 

installation of thermal oxidizers (about $412 million) to exceed the total EPA estimated costs 

identified in the CISWI Rule for all its intended sources. Based on EPA’s estimated annual costs 

of compliance for each facility ($186,000), we estimate WM’s annual compliance costs would 

exceed $50 million per year. Such costs would be a significant financial burden for WM, and 

would be ruinous to the many local governments that own and operate MSW landfills and 

combust landfill gas for control or as fuel. 

On May 13, 2011, the Director of the Office of Resource Conservation and Recovery wrote a 

letter to the American Forest and Paper Association, to provide clarification of Agency 

statements made in the Response to Comments Document indicating a change in interpretation 

of what constitutes a “contained gaseous material.” While the Office Director’s letter indicates 

that the Agency has not changed its previous positions, and that previous statements and 

interpretation remain effective, the Agency has not yet issued a technical correction to the 

Response to Comments Document, nor has it specifically addressed and clarified the regulatory 

status of landfill gas.

Because EPA has not taken action to stay or amend the NHSM Rule, it is imperative that the 

Agency clarify the CISWI Rule by confirming the longstanding definition of “solid waste” as 

extending only to “contained gaseous material” and by clarifying that the combustion of 

gaseous emission streams does not constitute the combustion of solid waste subject to the 

CISWI Rule.

The Boiler Rule Should Not Deter Use of Landfill Gas as an Alternative Fuel

WM believes that the Boiler Rule, as published, creates a significant disincentive to using landfill 

gas as an alternative, renewable fuel. Our primary concern is that EPA has categorized landfill 

gas as a Gas 2 fuel, and thereby subjected landfill gas-fired units to unreasonable emission 

limitations that will be cost prohibitive to meet. Further, although EPA has created a fuel 

specification for “other Gas 1 fuels” by which landfill gas and other gases may qualify for Gas 1 

regulatory treatment, the fuel specification does not provide a viable avenue by which landfill 

gas would be relieved of the regulatory burdens associated with unnecessarily stringent 

emission limits. WM is encouraged that EPA has acknowledged in its National Emission 
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Standards for Hazardous Air Pollutants; Notice of Reconsideration (“Reconsideration Notice”) 

published at 75 Fed. Reg. 15266 (March 21, 2011) that this and other provisions of the Boiler 

Rule are of central relevance to the rule and arose after the period for public comment, and 

were impracticable to comment upon. WM supports EPA’s Reconsideration Notice on that 

basis and submitted a petition to the Agency to reconsider and amend the Boiler Rule. We 

have appended our petition for reconsideration as Attachment B.

Specifically, WM requested that the Agency reconsider its categorization of LFG as “Gas 2” 

under the Boiler Rule, and amend the rule to clarify that landfill gas constitutes a “Gas 1” fuel 

for which the imposition of emission limits is infeasible and impracticable. Alternatively, to the 

extent that landfill gas may only quality for “Gas 1” categorization through a fuel specification, 

WM requests that EPA revise the specification to ensure that it is established in a manner which 

will include landfill gas that is managed in accordance with existing Clean Air Act requirements, 

and which will ensure that landfill gas may be combusted without the imposition of 

burdensome sampling and analysis requirements. Finally, landfill gas-fired units should not be 

subject to emission limits under the Boiler MACT. The emission limits established for Gas 2 

units are technically infeasible and cost prohibitive to promoting renewable sources of energy.

Landfill Gas Should be Identified as a Gas 1 Fuel

Waste Management contracted with CH2MHill to conduct a comparison of the emissions 

properties of boilers firing landfill gas as fuel to those of boilers firing Gas 1 fuels, and to 

examine the publicly available information to compare landfill gas to Gas 1 fuels, specifically 

natural gas and refinery gas. (The report is appended to our comments as Attachment C.)

As described in the appended report, CH2MHill concluded that sufficient data were readily 

available for EPA to establish that LFG is comparable to natural gas and refinery gas with regard 

to HAP emissions, and that both emissions and raw gas analysis data support the conclusion 

that LFG should be classified as a Gas 1 fuel. A brief summary of the report conclusions follows:

A comparison of the readily available data for landfill gas-only fueled boiler emissions indicates 

that the ranges of reported results for mercury, PM, CO, and dioxin/furans are within or below 

the ranges of these parameters for one or both of the recognized Gas 1 fuels -- natural gas and 

refinery gas. No HCl data were available for refinery gas for comparison to landfill gas; 

however, the few HCl emissions data points available from landfill gas-fueled boilers (0.00321 

to 0.00398 pounds per million British thermal units [lb/MMBTU]) are lower than the Boiler 

MACT emission limits for existing coal-fired units (0.035 lb/MMBTU).

Mercury levels in raw landfill gas from 15 landfills reported in EPA’s BID (2008) for Revisions to 

the AP-42 Emission Factors for Municipal Solid Waste (MSW) Landfills indicated a range of total 

mercury orders of magnitude lower than the available data for mercury in natural gas. A 

comparison of the constituents of raw landfill gas to the recognized Gas 1 fuels is inconclusive 
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with respect to the other HAP and surrogate parameters because of the dearth of available 

data for the Gas 1 fuels.

Data developed by EPA in its 2008 BID support the conclusion that the mercury level in landfill 

gas is consistently much lower than the Gas 1 fuel specification level of 40μg/m3. 

EPA based its H2S fuel specification of 4 ppmv on sweetened, pipeline-quality natural gas; 

however, refinery gas (already categorized as Gas 1) typically contains much higher levels of H2S 

than the Gas 1 fuel specification. CH2MHill noted that the H2S concentrations in refinery gas 

can range from 0 to 450,000 ppm. The range of H2S concentrations in landfill gas noted in the 

EPA 2008 BID ranged from 0.00102 to 55.7 ppm. Landfill gas should not be held to a higher H2S 

standard than refinery gas for qualification as a Gas 1 fuel, especially considering that H2S is 

neither a HAP, a HAP precursor nor a surrogate for HAP emissions. 

Based on the above analysis, WM strongly recommends that landfill gas be categorized as 

Gas 1 under the Boiler Rule. The data for mercury and H2S in landfill gas support its 

characterization as a Gas 1 fuel. Further, should boiler owners switch fuel from landfill gas to 

one of the currently defined Gas 1 fuels, increased pollution emissions will occur. Use of 

natural gas or refinery gas will increase criteria pollutant and greenhouse gas emissions 

compared to landfill gas. Landfill gas has been shown to produce lower nitrous oxide emissions 

than natural gas, and using landfill gas lowers fossil carbon dioxide emissions as compared to 

both Gas 1 fuels.

EPA Should Revise the Gas 1 Specification 

To the extent that landfill gas, or any gaseous fuel may only qualify for Gas 1 categorization 

through a fuel specification, WM requests that EPA revise the specification to ensure that it is 

established in a manner that will include landfill gas that is managed in accordance with existing 

CAA requirements as discussed above and in more detail in Attachment B. For example, the 

Landfill MACT requires that landfill gas be routed to a treatment system that processes the gas 

for subsequent sale or use as fuel; this requirement would be an appropriate and adequate 

specification for demonstrating that landfill gas may be combusted as a Gas 1 fuel. 

Alternatively, to the extent that EPA determines that an H2S specification limit must apply, any 

such limit should be derived from an existing landfill gas combustion-related sulfur content 

limit. The NSPS (KKKK) for Stationary Turbines (40 CFR Part 60.4330) as revised in 2009, 

provides such a limit.

Landfill Gas Should Not be Subject to Additional Emission Limits When Used in 

Boilers

EPA has already evaluated, and regulated, HAP emissions that may result from the two 

circumstances under which landfill gas may be used in a boiler under the Landfill NSPS and the 

Landfill MACT. First, landfill gas fired directly to a boiler operating as a control device is subject 

to the non-methane organic compounds (NMOC) emission standard that was established 
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pursuant to the Landfill NSPS and determined under the Landfill MACT to adequately address 

HAP emissions. Imposition of additional emission limits from such control devices would 

constitute an impermissible duplication of emission limits under Section 112 of the CAA. 

Second, the Landfill NSPS and the Landfill MACT require that landfill gas used as a fuel must be 

treated and processed in a manner that ensures proper combustion in accordance with 

specifications required by the receiving combustion unit. Imposition of emission limits under 

the Boiler MACT for this use of landfill gas, where natural gas and refinery gas are not subject to 

such limits, would create an extreme disincentive to the use of landfill gas for energy recovery. 

For these reasons, the Gas 2 emission limits in the Boiler Rule should not apply to landfill gasfired boilers.

Waste Management appreciates the opportunity to share this additional information with the 

Agency, and looks forward to working with you as you reconsider and revise the Boiler and 

CISWI Rules. If you have any questions with our comments or with the attached materials, 

please feel free to contact me at (202) 639-1218 or by email at kkelly5@wm.com

Sincerely,

Kerry Kelly, Director

Federal Public Affairs