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EPA in Indiana

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Indiana (Part 60) Emission Guidelines and (Part 62) State/Federal Plans (Section 111d/129) Delegations

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Air Standards Delegations in Indiana

Clean Air Act (CAA) section 111(d), originally enacted in 1970, was intended to cover pollutants that are not regulated under either the criteria pollutant/NAAQS provisions or section 112 of the CAA.  It was designed to regulate pollutants from existing sources and new sources that fall in the gap not covered by the criteria pollutant provisions or the hazardous air pollutant provisions. In 1990, Congress added Section 129 to the CAA specifically to address emissions from solid waste combustion.

Sections 111 and 129 require EPA to establish new source performance standards (NSPS) for new units and require the Agency to establish Emission Guidelines for existing units. Both the NSPS and the Emission Guidelines under section 111(d)/129 use a Maximum Achievable Control Technology (MACT) type approach as used under Section 112.

  • New source performance standards (NSPS) are direct federal regulations that apply to new sources.
  • Emission guidelines do not directly regulate solid waste combustion units; they establish requirements for state plans, which are the vehicle by which states implement the guidelines.
  • Once approved, these state plans become federally enforceable.
  • If a state does not seek approval of a state plan, the federal plan applies.

Large Municipal Waste Combustors (Large MWC)

State Plan Approved

Hospital/Medical/Infectious Waste Incinerators (HMIWI)

State Plan Approved

Small Municipal Waste Combustors (Small MWC)

Negative Declaration but Federal Plan would apply if a source is found.

Commercial, Industrial Solid Waste Incinerators (CISWI)

Negative Declaration but Federal Plan would apply if a source is found.

Other Solid Waste Incineration (OSWI)

State Plan Approved

Sewage Sludge Incinerators (SSI)

Negative Declaration but Federal Plan would apply if a source is found.

Municipal Solid Waste (MSW) Landfills

State Plan Approved

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112 Major and Area Source Standards

EPA's final delegation approval of Section 112 NESHAP standards for Indiana constitutes a program of straight delegation of all existing and future air toxic standards regardless of a source's Part 70 (Title V) applicability, with the exception of Section 112(r). For future 112 NESHAP standards for which IDEM intends to accept delegation, EPA will automatically delegate the authority to implement a standard to the State by letter unless IDEM notifies EPA differently within 45 days of EPA final promulgation of the standard. Upon receipt of the EPA letter, IDEM will be responsible for the implementation of the standard. IDEM will then adopt the standard unchanged from the Federal standard into State regulations as expeditiously as practicable. IDEM will submit proof of rule adoption to EPA. EPA will respond with a letter delegating enforcement authority to the State. EPA will enforce the standard until such time the State has been delegated the enforcement authority.

IDEM has chosen not to take full or partial delegation of newly promulgated area source MACT standards.

112(L) Delegations to Indiana through a state rule that adjusts the MACT standard

Federal Register Documents for Approval of Section 112(l) Program of Delegation​

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