Wash. Rev. Code § 78.44.350
(2) The department may reduce the required performance security calculated from its standard method prescribed in RCW 78.44.087, to an amount not to exceed the sum of reclamation security calculated by the department for the two surface mines with the largest performance security obligations, for nonmetal and nonfuel surface mines that meet the following conditions:
[ 2006 c 341 s 4.]