NSHM Rule – Classification of Materials as Fuel or Waste for Combustion

Industrial PlantOn December 20, 2012, the US EPA promulgated several final rules for emissions standards for certain industrial boilers and incinerators. Also finalized at the same time was a rule that determines what standards apply to units that combust secondary materials, rather than traditional fuels. This rule is known as the Identification of Non-Hazardous Secondary Materials That Are Solid Waste (NSHM Rule), and it is important because the EPA determination of a particular fuel as a waste has ramifications for the unit in question. If a unit is firing a fuel determined as a waste, then it will be required to meet the more stringent standards for Commercial/Industrial Incinerators (CISWI), rather than the standards applicable to boilers, known under as MACT standards.

However, the criteria by which the EPA would determine whether a fuel is waste or non-waste has been very opaque since the outset, and early attempts to distinguish between the two categories were even a primary reason for earlier MACT and CISWI rules to be invalidated and vacated entirely. In 2011 EPA attempted to resolve this with the first NSHM rule, but again failed to establish clear and legally sound criteria for distinguishing between the fuel types. This led to the rule being reopened in March of 2011, the publishing of proposed changes in December of that year, and the Final Rule being promulgated in December of 2012.

The regulatory structure is one where the burden of proof is on the unit operator or owner of a unit firing secondary material to demonstrate that the fuel is not a waste, by demonstrating that it meets certain criteria to be a legitimate fuel, rather than the disposal of waste. For materials combusted by the generator (of the material) as fuels, these legitimacy criteria are demonstrated by whether the materials are:

  • Managed as a valuable commodity
  • Have sufficient heating value
  • Contain pollutants at levels comparable to or lower than a traditional fuel for the unit

For materials combusted by third parties (not the generator of the material), the material must meet those legitimacy criteria, and in addition must be either processed into non-waste by removing contaminants, or must be approved by a petition to the EPA.

Some materials that are combusted might be materials in the manufacturing process, and are known as ingredients. These ingredients can be defined as non-waste fuels by meeting a different set of legitimacy criteria.

  • In lieu of heating values, consider the contribution made by the material to the production or manufacturing process.
  • In lieu of evaluating inputs, the contaminant comparison is made by comparing the product produced using the secondary materials to products made using virgin materials.

Ingredient materials meeting these legitimacy criteria can be combusted by both the generator and third parties without requirement for processing or a petition.

Another step taken in the December 2012 rule was the creation of an additional mechanism to identify non-waste fuels by categorical determination. Under this aspect, the EPA may consider any relevant factor, and can list a material as a non-waste fuel even when it does not meet one or more of the legitimacy criteria. These listed fuels can then be combusted without making individual determinations that the fuel is legitimate. However, this mechanism does not apply to materials used as ingredients.

There are already four (4) categories of materials that have been established to not be wastes when combusted, they are:

  • Scrap tires that are not discarded and are managed under established tire collection programs
  • Resinated wood
  • Coal refuse recovered from legacy piles and processed in the same manner as currently generated coal refuse
  • Dewatered pulp and paper sludges that are not discarded and are generated and burned on-site by pulp and paper mills

Future potential categorical listings may also include construction and demolition wood, paper recycling residuals, railroad ties, and treated wood.

The compliance deadline for Boilers is three years, and for CISWI units is five years. Regardless, it is important to make the determination of fuel classification in the immediate, to prepare strategies for compliance with these new emission limits. If an operator combusts a waste after the compliance deadline for the CISWI, even if the waste is burned inadvertently, or if process data is not maintained on secondary materials being burned, then the unit would immediately become a CISWI and be regulated as such for six (6) months. Due to the more stringent requirements, in practical terms this means that many units would have to be shut down for that period of time.

In all aspects of compliance with MACT and CISWI, and other EPA rules and regulations, ESS has experience and the network to facilitate any air-quality needs. For assistance with topics from emissions testing to control device strategies, we are here to assist.  Please call our experts at (910) 799-1055.

Brian Mellor About Brian Mellor

Brian Mellor works with Environmental Source Samplers, Inc. (ESS), an environmental consulting firm specializing in stack testing, CEMS Testing, and EPA air emissions compliance.

ESS has conducted international stack testing projects at Johnson Atoll, in the Philippines, the Dominican Republic, Hong Kong, and various parts of Europe. If you need a team that will do your international job with efficiency and effectiveness, call ESS at (910) 799-1055 or visit www.ESSKnowsAir.com.

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