You may complete an on-line application at the Contra Costa Human Resources Department at 651 Pine St., 2nd Floor, Martinez, CA 94553. Posted on: July 27, 2021.Contra Costa Canal Safety Reminder. 1 shall be included in the West Contra Costa. Applicants are supposed to respond to the letter within 30 days from the sent date. May 21, 2019 Meeting Summary. Work as specified in the resignation letter. 2.