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Frequent Questions About the Emission Comparable Fuel Expansion (ECF)

Withdrawal of the Emission-Comparable Fuel Exclusion
May 2010 Final Rule Frequent Questions

1. What are Emission-Comparable Fuels?

Emission-comparable fuels (ECF) are those hazardous secondary materials which have fuel value and whose hazardous constituent levels are comparable to those found in fuel oil that could be burned in their place.

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2. What does this rule do?

This rule withdraws the December 2008 Emissions-Comparable Fuel Exclusion rule.

The December 2008 rule was a conditional exclusion stating that hazardous secondary materials that meet all of the hazardous constituent specifications applicable to comparable fuel, except those for oxygenates and hydrocarbons, and that are burned and stored under prescribed conditions, are not discarded and thus, are not solid wastes.

This rule will result in ECF being regarded as discarded material and regulated as hazardous waste.

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3. How does this rule differ from the proposed rule to Withdraw the ECF Exclusion?

This rule is virtually identical to the December 8, 2009 proposal Withdrawal of the ECF (74 FR 64643). The Agency received no major comments during the public comment period.

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4. Why is EPA withdrawing the ECF exclusion?

EPA is withdrawing the ECF exclusion due to difficulty ensuring that emissions from burning ECF are comparable to emissions from burning fuel, the limited savings from burning ECF, and the difficulty administering the rule.

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Expansion of RCRA Comparable Fuel Exclusion
May 2007 Proposed Rule Frequent Questions

1. What is the rationale for excluding emission-comparable fuel from the definition of solid waste?

Emission-comparable fuel (ECF) meets the comparable fuel specifications in Table 1 to §261.38 (except the specifications for hydrocarbons and oxygenates), and the specifications for heating value and viscosity as generated.  ECF has substantial fuel value and the hydrocarbon and oxygenate constituents provide substantial fuel value.  In addition, emissions from burning ECF are comparable to emissions from burning fuel oil.  Consequently, ECF is a fuel product when burned and stored under the conditions of the exclusion.

Classifying such material as a fuel product and not as a waste promotes RCRA’s resource recovery goals without creating a risk from burning greater than those posed by fossil fuel.  Under these circumstances, EPA has discretion to classify such material as a fuel product, and not as a waste.  See generally Safe Foods and Fertilizer v. EPA, 350 F. 3d 1263, 1269-71 (D.C. Cir. 2004) (secondary materials physically comparable to virgin products which would be used in their place, or which pose similar or otherwise low risks when used in the same manner as the virgin product, need not be considered “discarded” and hence need not be classified as solid wastes).

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2. RCRA already excludes certain secondary materials under 40 CFR 261.38 from being designated as solid (and hazardous) waste. How is EPA expanding the comparable fuels exclusion?

Through this final rule, EPA is expanding Comparable Fuels Exclusion to encompass a new category of liquid hazardous secondary materials known as emission-comparable fuel (ECF). ECF will join synthesis gas and comparable fuels under the Comparable Fuels Exclusion. These fuels are energy-rich hazardous secondary materials which would otherwise be hazardous wastes, but which have the same hazardous constituent concentrations as fossil fuels that would be burned in their place.

ECF is subject to the same regulations that currently apply to the Comparable Fuels Exclusion, with the exception of those for oxygenates and hydrocarbons (constituents which contribute energy value to the fuel).  The rule specifies conditions on burning ECF which assure that emissions from industrial boilers burning ECF are comparable to emissions from industrial boilers burning fuel oil.  The ECF exclusion also includes conditions for tanks and containers storing ECF to prohibit improper disposal.

Industrial boilers also must comply with the existing requirements under the Clean Air Act (CAA).

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3. Which specifications of the comparable fuels exclusion do not apply to the emission-comparable fuel exclusion and why?

ECF meets all of the hazardous constituent specifications (over 160) for comparable fuel, with the exception of those for oxygenates and hydrocarbons (constituents which contribute energy value to the fuel). The specifications for hydrocarbons and oxygenates do not apply to emission-comparable fuel (ECF) because:  (1) hydrocarbons are found in fuel oil and the oxygenates are a class of compounds that are added to fuels to enhance combustion; and (2) when ECF is burned under good combustion conditions and at the feedrates limited under the exclusion, the emissions of hazardous compounds will be comparable to those from burning fuel oil.  The feedrate limit for each ECF constituent ensures that ECF emissions will be comparable to fuel oil and protective of human health and the environment. 

In addition, the specifications are retained for the other categories of compounds listed in Table 1 to §261.38.  The specifications for metals are retained because metals do not contribute energy and are not destroyed during the combustion process.  Also, it is appropriate to retain the specifications for the other categories of organic compounds:  sulfonated organics, nitrogenated organics, and halogenated organic compounds.  These organic compounds, for the most part, are not likely to be found in fuel oil or gasoline, the benchmark fuels EPA used to establish the specifications.  Furthermore, unlike oxygenates, these organic compounds are not within a class of compounds that are added to fossil fuels to enhance combustion.  These hazardous compounds would appear to be “along for the ride” when present at concentrations higher than benchmark fuels, and consequently their destruction via combustion can be viewed as waste management.

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4. Why is EPA excluding emission-comparable fuel (ECF) from the definition of solid (and hazardous) waste?

The ECF exclusion will correct the market distortions associated with unnecessary regulatory constraints that prevent the most efficient use of the fuel value of hazardous secondary materials.  Under current regulations, these hazardous secondary materials are managed as hazardous waste and are often shipped off-site to commercial hazardous waste combustors for use as fuel.  EPA believes that these hazardous secondary materials can be burned for energy recovery without imposing unnecessary regulatory costs on generators, primarily the manufacturing sector.  Continuing to regulate these fuels as hazardous wastes would treat a potentially valuable fuel commodity (especially considering the increasing price of fuels) as a waste without a compelling basis.

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5. What are the major changes to the proposed rule?

Major Changes to the Storage Conditions:

Major Changes to the Burner Conditions:

Major Changes to the Implementation Conditions:

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6. What risk assessments have been conducted to evaluate the protectiveness of burning emission-comparable fuel (ECF)?

EPA concluded that emissions from burning ECF would generally be protective of human health for several reasons.  First, the ECF boiler operating conditions relating to destruction of organic compounds are at least as stringent as those applicable to hazardous waste boilers.  Given that EPA concluded that hazardous waste boiler emissions are generally safe, ECF boiler emissions are also generally safe. 

Second, EPA reviewed the RCRA risk assessments that were completed by June 2006 for hazardous waste boilers to determine if organic emissions under the good combustion conditions required by the RCRA standards may result in unacceptable risk to human health and the environment.  That analysis confirmed that organic emissions from ECF boilers operating under the prescribed burner conditions should be protective.

Finally, EPA also conducted an abbreviated comparative risk assessment for dioxin/furan emissions from boilers burning hazardous waste and that meet the design conditions for an ECF boiler.  The abbreviated evaluation used one component of the comparative risk evaluation used to support the Phase II hazardous waste combustor maximum achievable control technology (MACT) for boilers—the Margin of Exposure (MOE) analysis.  Within the limitations of the analyses, EPA concluded that dioxin/furan emissions from ECF boilers are likely to pose no greater hazard than the emissions from hazardous waste incinerators, and therefore, should remain within levels that are protective.

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7. Who will benefit by the emission-comparable fuel exclusion and who will be adversely affected?

Generators of hazardous secondary materials that meet the conditions of the emission-comparable fuel (ECF) exclusion will realize reduced management costs because they could manage these fuels without being subject to regulation as hazardous waste.  In addition, generators will benefit from fuel savings if ECF were burned on-site or from fuel revenues if ECF were burned off-site. 

Commercial hazardous waste combustors that are currently managing hazardous secondary materials that qualify as ECF might find themselves unable to continue to charge hazardous waste management fees for the excluded fuels.  Consequently, commercial hazardous waste combustors might lose the waste management revenues for those diverted fuels and may need to meet their heat input requirements by using other waste fuels or fossil fuels.

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8. Will the ECF exclusion result in an increase in emissions of pollutants?

Emissions from burning ECF under the exclusion will be no greater than emissions from the current practice of burning the hazardous secondary materials in hazardous waste combustors.  This is because the conditions for burning ECF are at least as stringent as the current requirements for burning hazardous waste fuels.

Boilers that burn ECF in the place of natural gas may register an increase in emissions of pollutants.  However, the emissions from these facilities will be no higher than if these boilers burned fuel oil.

In addition, cement kilns that currently burn hazardous secondary materials that become ECF may decide through their fuel pricing policies not to compete with boilers to purchase ECF.  (To the extent that cement kilns need or choose to burn fuels cleaner than coal, they should pay the true market value for those fuels.  They should not rely on EPA regulations that regulate a fuel product as a hazardous waste to artificially devalue the fuels for their benefit.)  If ECF is diverted from cement kilns to industrial boilers, cement kilns may use coal to replace the ECF, while many industrial boilers will replace natural gas with ECF.  This raises the question of whether the exclusion may result in an increase in emissions of pollutants.

Although SO2 emissions from some types of cement kilns that choose to replace ECF with coal may increase, we note that the state regulatory authority will determine under the State Implementation Plan (SIP) if the increase in emissions must be further controlled pursuant to the area’s attainment or maintenance of the relevant National Ambient Air Quality Standard (NAAQS).  We have considered the potential cost of controlling the additional SOx emissions when we determined that the ECF exclusion will provide approximately $13 million annually in net benefits.

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9. How much emission-comparable fuel is expected to be excluded?

EPA estimates that up to 118,500 tons per year of hazardous secondary materials may be excluded.

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10. Why does EPA believe that emission-comparable fuel will have emissions comparable to fuel oil?

EPA compared hazardous waste boiler emissions as a surrogate for emission-comparable fuel (ECF) boiler emissions to oil-fired boiler emissions and concluded that there was no reason to believe that ECF emissions would not be comparable to oil emissions.  Hazardous waste boiler emissions can be used as a surrogate for ECF emissions because the ECF boiler operating conditions relating to destruction of organic compounds are at least as stringent as those required for hazardous waste boilers. 

In addition, a feedrate limit for each ECF constituent (i.e., hydrocarbon or oxygenate for which the comparable fuel exclusion does not apply) is established to provide objective assurance that emissions will be comparable.

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11. Did EPA make any changes to the existing comparable fuels (CF) exclusion?

EPA amended several provisions of the existing comparable fuels exclusion (CF) to clarify the exclusion and to conform with relevant provisions of the expanded exclusion for emission-comparable fuel (ECF).  These amendments relate to:  (1) consequences of failure to satisfy conditions of the CF exclusion, (2) regulatory status of tanks ceasing to operate as CF storage tanks, (3) waiver of RCRA closure requirements for tanks used for hazardous wastes that are subsequently excluded as CF, (4) regulatory status of boiler residues, and (5) information to be provided in the one-time notice by generators to the regulatory authority.

In addition, the final rule restructures the current conditions for comparable fuel (and synthesis gas fuel) to make the regulatory language more readable, given that the regulation must accommodate the expansion for ECF.

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