Cal. Mil. & Vet. Code § 1176
Within 30 days after the filing of the petition the county elections official shall find and certify whether the petition is signed by the requisite number of qualified registered voters of the proposed district and of the incorporated and unincorporated portions thereof and shall present the petition with the certificate of his or her findings attached thereto to the board of supervisors at its first regular meeting held 10 days from the date of certification of the petition. The board shall fix a time and place for the hearing of the petition not less than 20 days nor more than 40 days after the date of the meeting, and shall direct the clerk of the board to publish a notice once a week for three successive weeks in a newspaper circulated in the territory that it is proposed to organize into a district, and that the board deems most likely to give notice to the inhabitants of the territory.
Ca. Mil. and Vet. Code § 1176