35 Ill. Adm. Code 204.650
Secondary Emissions
Section 204.650 Secondary Emissions
"Secondary emissions" means emissions that
would occur as a result of the construction or operation of a major stationary
source or major modification, but do not come from the major stationary source
or major modification itself. Secondary emissions include emissions from any
offsite support facility that would not be constructed or increase its
emissions, except as a result of the construction or operation of the major
stationary source or major modification. Secondary emissions do not include
any emissions that come directly from a mobile source, such as emissions from
the tailpipe of a motor vehicle, from a train, or from a vessel. For the
purposes of this Part, secondary emissions must be specific, well defined,
quantifiable, and impact the same general area as the major stationary source or
major modification which causes the secondary emissions.