A county noxious weed control board may be deactivated only if there are neither any class A noxious weeds nor any class B noxious weeds in the county. Upon receiving documentation of the absence in the county of both class A noxious weeds and class B noxious weeds, the county legislative authority may initiate the following procedures:

(1) The county legislative authority holds a hearing to determine whether there continues to be a need for an activated county noxious weed control board if:

(a) A petition is filed by one hundred registered voters within the county;

(b) A petition is filed by a county noxious weed control board as provided in RCW 17.10.240; or

(c) The county legislative authority passes a motion to hold such a hearing.

(2) Except as provided in subsection (4) of this section, the hearing shall be held within sixty days of final action taken under subsection (1) of this section.

(3) If, after a hearing, the county legislative authority determines that no need exists for a county noxious weed control board, due to the absence of class A or class B noxious weeds designated for control in the region, the county legislative authority shall deactivate the board.

(4) The county legislative authority shall not convene a hearing as provided for in subsection (1) of this section more frequently than once a year.