35 Ill. Adm. Code 204.270
Begin Actual Construction
Section 204.270 Begin Actual Construction
"Begin actual construction" means, in general,
initiation of physical on-site construction activities on an emissions unit that
are of a permanent nature. Such activities include, but are not limited to,
installation of building supports and foundations, laying underground pipework,
and construction of permanent storage structures. With respect to a change in
method of operations, this term refers to those on-site activities other than
preparatory activities that mark the initiation of the change.