Wash. Rev. Code § 7.04A.200
(1) On motion to an arbitrator by a party to the arbitration proceeding, the arbitrator may modify or correct an award:
(4) If a motion to the court is pending under RCW 7.04A.220, 7.04A.230, or 7.04A.240, the court may submit the claim to the arbitrator to consider whether to modify or correct the award:
[ 2005 c 433 s 20.]