(a) Computation. In computing any period of time set forth in this part, except as otherwise provided, the day of the event from which the designated period begins to run shall not be included. Saturdays, Sundays, and Federal legal holidays shall be included. When a stated time expires on a Saturday, Sunday or Federal legal holiday, the stated time period shall be extended to include the next business day.

(b) Extensions of time. A DOE Official may grant an extension of any time period set forth in this part.

(c) Service by mail. Where a pleading or document is served by mail, five (5) days shall be added to the time allowed by these rules for the filing of a responsive pleading or document. Where a pleading or document is served by express mail, only two (2) days shall be added.