For good cause shown, the Board may permit any interested party to
intervene or otherwise participate in any proceeding held by the Board.
Except when requested orally before the Board, a petition to intervene
or otherwise participate shall be in writing (original and four copies)
and shall state with precision and particularity:
(a) The petitioner's relationship to the matters involved in the
proceedings, and
(b) The nature of the presentation which the peititioner would make.