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:

1. (a) The petitioner's relationship to the matters involved in the proceedings, and
2. (b) The nature of the presentation which the peititioner would make.