When actions are exempted from the requirements of SEPA or the SEPA guidelines because they are actions which must be taken immediately, or within a time too short to allow full compliance with SEPA or the SEPA guidelines to avoid an imminent danger to public or private property, or to prevent an imminent threat of serious environmental degradation, the responsible official shall prepare a written statement showing the nature of the action and the reasons for immediate action. Such statement shall be filed in the commission's SEPA public information center.