35.50.090 Expiration of permits and permit exemptions.
(1) The following time requirements shall apply to all permit exemptions, substantial development permits, and to any development authorized pursuant to a variance permit or conditional use permit:
(a) Construction shall be commenced or, where no construction is involved, the use or development activity shall be commenced within two years of the effective date of the permit or permit exemption; provided, that the review authority may authorize a single extension for a period not to exceed one year based on reasonable factors, if a request for extension has been filed before the expiration date and notice of the proposed extension is given to parties of record and the Department of Ecology.
(b) Authorization to conduct development activities shall terminate five years after the effective date of a permit or permit exemption; provided, that the Administrator may authorize a single extension for a period not to exceed one year based on reasonable factors, if a request for extension has been filed before the expiration date and notice of the proposed extension is given to parties of record and the Department of Ecology.