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Final Rule on Additions to the List of Categorical Non-Waste Fuels: Other Treated Railroad Ties

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Rule Summary

EPA is adding three materials to the list of categorical non-waste fuels under title 40 of the Code of Federal Regulations (CFR) Part 241 standards for combustion of Non-Hazardous Secondary Materials (NHSM). The three materials are:

  1. Creosote-borate and mixtures of creosote, copper naphthenate and copper naphthenate-borate treated railroad ties that are processed and then combusted in the following types of units: (i) Units designed to burn both biomass and fuel oil as part of normal operations and not solely as part of start-up or shut down operations; (ii) Units at major source pulp and paper mills or power producers subject to 40 CFR 63 Subpart DDDDD that had been designed to burn biomass and fuel oil, but are modified (e.g. oil delivery mechanisms were removed) in order to use natural gas instead of fuel oil as part of normal operations and not solely as part of start-up or shut down operations; and (iii) Units in (i) and (ii) that are also designed to burn coal.
  2. Copper naphthenate treated railroad ties combusted in units designed to burn biomass, biomass and fuel oil or biomass and coal.
  3. Copper naphthenate-borate ties combusted in units designed to burn biomass, biomass and fuel oil or biomass and coal.

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Rule History

This final rule builds upon the base NHSM regulatory program established on March 21, 2011. The NHSM regulatory program under 40 CFR Part 241 provides the standards and procedures for identifying whether NHSMs are solid waste under the Resource Conservation and Recovery Act (RCRA) when used as fuels or ingredients in combustion units:

  • Combustion units that burn NHSMs that are not solid waste under RCRA would be subject to the section 112 Clean Air Act requirements for commercial, industrial or institutional boilers or cement kilns

  • Combustion units that burn NHSMs that are solid waste under RCRA would be subject to the section 129 CAA requirements for solid waste incinerators.

Through the February 7, 2013 final NHSM rule, EPA added a process for stakeholders to request categorical non-waste determinations and provided a process to add additional NHSMs to the list of categorical non-waste fuels in 40 CFR section 241.4. On November 1, 2016, EPA proposed to add three additional materials to the list, which has been finalized.

EPA believes that identifying appropriate categorical non-waste fuels provides greater clarity to the regulated community and the public, reduces the burden on the regulated community by not requiring facilities to document individual determinations that these materials meet legitimacy criteria and streamlines NHSM regulation compliance for the regulated community.

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Additional Resources

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