The definitions in this section apply throughout this chapter unless the context clearly requires otherwise.

(1) "Banking instrument" means the documentation of agency and bank sponsor concurrence on the objectives and administration of the bank that describes in detail the physical and legal characteristics of the bank, including the service area, and how the bank will be established and operated.

(2) "Bank sponsor" means any public or private entity responsible for establishing and, in most circumstances, operating a bank.

(3) "Credit" means a unit of trade representing the increase in the ecological value of the site, as measured by acreage, functions, and/or values, or by some other assessment method.

(4) "Department" means the department of ecology.

(5) "Wetlands mitigation bank" or "bank" means a site where wetlands are restored, created, enhanced, or in exceptional circumstances, preserved expressly for the purpose of providing compensatory mitigation in advance of authorized impacts to similar resources.

(6) "Mitigation" means sequentially avoiding impacts, minimizing impacts, and compensating for remaining unavoidable impacts.

(7) "Practicable" means available and capable of being done after taking into consideration cost, existing technology, and logistics in light of overall project purposes.

(8) "Service area" means the designated geographic area in which a bank can reasonably be expected to provide appropriate compensation for unavoidable impacts to wetlands.

(9) "Unavoidable" means adverse impacts that remain after all appropriate and practicable avoidance and minimization have been achieved.