A petition by Northgate High parents to join the Acalanes and Walnut Creek school districts has passed a legal review by Contra Costa County attorneys, clearing a key first hurdle.

Ruth Carver of Walnut Creek crafted a plan to redraw district attendance lines after she became dissatisfied with the Mt. Diablo school district's handling of teacher vacancies at Northgate.

Her proposal would take Bancroft, Valle Verde, Walnut Acres elementary schools and Foothill Middle School from the Mt. Diablo and make them a part of the Walnut Creek School District, which serves students in kindergarten through eighth grade.

The change would also take some students who live in northwest Walnut Creek out of Pleasant Hill schools and add them to the newly enlarged elementary district. Northgate High would become part of the Acalanes Union High School District and no longer accept students in Crystyl Ranch and The Crossings neighborhoods in Concord.

County lawyers found that the petition meets legal requirements, said Peggy Marshburn, spokeswoman for the Contra Costa County Office of Education. Now the county registrar of voters must verify signatures.

Carver needs 10 percent of the Walnut Creek School District's 29,321 registered voters to sign before the petition can go to a hearing before the Contra Costa County Board of Education.

Carver turned in a first round of signatures on Jan. 25. Ellen Elster, deputy superintendent of the county office of education, said the petition included roughly 2,900 signatures. Carver turned in another 200 or so last week.