Stevens Creek Quarry is an active bluestone aggregate mining operation located in the Stevens Canyon area south of Cupertino. In 2020, Harvey Rose Associates, at the request of Supervisor Simitian, conducted an independent review that identified several deficiencies in the County Department of Planning and Development’s oversight of the Quarry. This effort, spurred by Supervisor Simitian’s advocacy for more rigorous oversight of the Quarry, resulted in the improved monitoring and enforcement of use-permit conditions at the Quarry.