Wash. Rev. Code § 87.03.100
As soon as all the votes are read off and counted, a certificate shall be drawn upon each of the papers containing the poll list and tallies, or attached thereto, stating the number of votes each one voted for has received, and designating the office to fill which he or she was voted for, which number shall be written in figures and in words at full length. Each certificate shall be signed by the clerks, judges, and the inspector. One of said certificates, with the poll list and the tally paper to which it is attached, shall be retained by the inspector, and preserved by him or her at least six months. The ballots, together with the other of said certificates, with the poll list and tally paper to which it is attached, shall be sealed by the inspector, in the presence of the judges and clerks, and endorsed "Election returns of [naming the precinct] precinct," and be directed to the secretary of the board of directors, and shall be immediately delivered by the inspector, or by some other safe and responsible carrier designated by said inspector, to said secretary, and the ballots shall be kept unopened for at least six months, and if any person be of the opinion that the vote of any precinct has not been correctly counted, he or she may appear on the day appointed for the board of directors to open and canvass the returns, and demand a recount of the vote of the precinct that is so claimed to have been incorrectly counted.
RCW 87.03.100