No rule proposed after July 1, 1989, is valid unless it is adopted in substantial compliance with RCW 34.05.310 through 34.05.395. Inadvertent failure to mail notice of a proposed rule adoption to any person as required by RCW 34.05.320(3) does not invalidate a rule. No action based upon this section may be maintained to contest the validity of any rule unless it is commenced within two years after the effective date of the rule.