47 Ill. Adm. Code 395.303
Parties
Section 395.303 Parties
a)
Substitution of the Parties: The Board
may, on motion, at any time in the course of any proceeding, permit a
substitution of parties as justice or convenience may require.
b)
Intervention: The Board may allow any
person or persons showing that they may be substantially and specifically
affected by the proceedings to intervene as a party in the whole or in any
portion of the proceedings. The Board may allow any other interested person to
participate by presentation of argument orally or in writing or for any other
limited purpose, as the Board may order. The Board shall not allow a person to
intervene if his or her interests are substantially similar to those of any
party and no showing is made that one or more of the parties will not
diligently represent those interests. Being a resident, land owner or taxpayer
of a Local Government, with no other showing of an issue that is not being
adequately addressed by one of the parties, shall not be sufficient to sustain
intervention.