(1) Conditions of issuance. The department may approve and issue to any person, an implementation schedule for meeting any particular requirement of this chapter, if it finds that immediate compliance with such requirement cannot be achieved because of conditions beyond the control of such person or because of special circumstances rendering immediate compliance unreasonable in light of economic or physical factors or because of the nonavailability of feasible technology or control methods.

(2) Requesting procedure. Implementation schedules shall be issued only upon application in writing to the department. Such application shall state in a concise manner the facts to show cause why such schedule should be approved. Any aggrieved person may appeal the department's decision on an application to the pollution control hearings board pursuant to chapter 43.21B RCW.