Burning “waste” or “fuel” triggers potentially very difference air emissions limits. On Dec. 23, 2011, the United States Environmental Protection Agency (EPA) proposed Clean Air Act Rules to revise the Identification of Non-Hazardous Secondary Materials that are Solid Wastes (NHSM Rule) and the Standards of Performance for New Stationary Sources and Emissions Guidelines for Existing Sources: Commercial and Industrial Solid Waste Incineration Units (CISWI Rule), as well as two other rules relating to industrial boilers (covered on a separate Alert being issued today). The following is a summary of the proposed changes to the NHSM Rule, with references to the proposed reconsideration of the CISWI Rule where relevant. EPA will only take comment on these changes, and not on the underlying Final Rules. Comments on the proposed Rules must be received on or before Feb. 21, 2012.

These proposed Rules amend the NHSM Rule and the CISWI Rule, which were both published on March 21, 2011. The NHSM Rule became effective on May 20, 2011. The CISWI Rule was stayed and has not gone into effect. These Rules are linked because the NHSM Rule defines what is a “waste,” and any unit that combusts a waste is a CISWI unit subject to the CISIW Rule (and not the Boiler MACT or other MACT standard).

Many parties filed petitions for reconsideration of the CISWI Rule, petitions for rulemaking to revise the NHSM Rule, and petitions for review of both Rules in the D.C. Circuit Court of Appeals. EPA agreed to reconsider the CISWI Rule. However, EPA initially refused to reopen the NHSM Rule, preferring to address issues through guidance rather than rulemaking. Finally, in October 2011, after legislation passed the House of Representatives that would force EPA to revise the NHSM Rule, as well as the CISWI Rule and the Boiler MACT Rule, EPA sent a letter to the lead sponsors of the companion Senate Bill informing them that they would issue a formal proposal to revise the NHSM Rule.

NHSM Regulatory Proposals

Definitions: EPA is proposing changes to three definitions: clean cellulosic biomass (providing more examples), contaminant (adding precursors and dropping products of combustion and contaminants not expected to be found in non-hazardous secondary material), and established tire collection program (making technical changes to include off-specification tires and programs established by contract).

Presumption of discard: In response to the concern that EPA has categorically defined all secondary materials that are transferred to third parties as wastes, EPA is proposing to change the language of 40 CFR 241.3(a) to say that “non-hazardous secondary materials that are combusted are presumed to be solid wastes.” Thus, EPA is opening up for comment the issue of the scope of its authority under RCRA and where the burden should lie when making a determination whether a material is or is not a “waste.”

Contaminant legitimacy criterion: In response to the concern that many legitimate fuels would be classified as wastes under the NHSM Rule, EPA is proposing to change the legitimacy criterion relating to levels of contaminants (proposing to amend 40 CFR 241.3(d)(iii)). First, EPA adds the phrase “or groups of contaminants” to the regulatory language to allow a combustor to look at classes of contaminants, not individual contaminants, when determining whether the levels are comparable to levels found in traditional fuels. Second, when identifying what traditional fuels may be used for comparison, EPA proposes to clarify in the regulatory language that the term “designed to burn” does not mean that a unit must be permitted to burn or actually burn a particular traditional fuel to allow a comparison to that fuel. Third, EPA proposes to clarify in the regulatory language that, when making comparisons, “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.” EPA has added some national survey data to its website.

Non-waste determination: In response to the concern that the NHSM Rule would identify NHSM as waste even when its overall use as a fuel is legitimate, EPA is proposing to add new section 241.4 to the Rule, to provide a regulatory process for EPA to make national determinations that certain categories of materials are non-wastes, even if they do not meet all the legitimacy criteria. EPA is proposing to identify scrap tires managed in an established tire collection program and resinated wood as non-wastes and is taking comment on two other materials.

In general, the proposed changes to the NHSM Rule will make it easier for a combustor to demonstrate that a secondary material is not a waste. However, the burden of proof that a fuel is a non-waste remains on the combustor. The CISWI Rule requires a combustor to keep records supporting this determination of legitimacy. Failure to keep records turns the NHSM material (even if legitimate) into a waste and the combustion unit into a CISWI unit.

Relevant CISWI Provisions

Contained gaseous material: In the proposed revisions to the CISWI Rule, EPA proposes to keep the existing definition of contained gaseous material. Both the CISWI proposal and the NHSM proposal also include preamble language stating that there is no intent to change EPA’s interpretation of what constitutes a contained gas under RCRA. Thus, EPA has reaffirmed its long-standing position that contained gases (which are solid wastes under RCRA) include only gases in containers, and not gases in pipelines, so flares are not automatically CISWI units.

Other definitions: EPA is taking comment on other CISWI definitions including: burn-off oven, chemical recovery unit, cyclonic burn barrel, foundry sand thermal reclamation unit, homogenous wastes, laboratory analysis unit, soil treatment unit, space heater, and waste burning kiln. These definitions are important because they define what is and is not subject to the CISWI Rule.