A Sonoma County judge's ruling effectively dismisses one of three lawsuits filed to stop a rock quarry on Roblar Road west of Cotati.

Neighbors of quarry developer John Barella had sued him and the county open space district, challenging Barella's right to use adjoining property to establish a preserve for the endangered tiger salamander.

Such a preserve is required for construction of the quarry and has been sanctioned by open space officials.

In a 27-page ruling issued late last month, Superior Court Judge Elliot Daum concluded that neighbors Joseph and Kathleen Tresch, along with a citizens group opposing the quarry, had no basis for their claim under California environmental law.

Daum ruled their lawsuit does not state a valid cause of action and that opponents cannot in the future amend their claim. Daum is expected to issue a final judgment leading to a dismissal.

Two other lawsuits attempting to stop the 70-acre quarry approved in December by the county board of supervisors are pending.

Opponents claim it would harm water and air quality, increase traffic and hurt wildlife in nearby county-protected open space.