Forest Closes Location of the Historic Big Blue Mill Site to Public Access

The Sequoia National Forest has closed the Historic Big Blue Mill Site due to elevated levels of metals that were determined to be a potential risk to public health.

Elevated levels of arsenic, lead, and mercury has been detected in the soils and mill tailings at this Site, which greatly exceeds background levels and established human health risk screening thresholds and indicates there is a potential exposure hazard to site visitors and nearby residents.

Due to the potential public health risks associated with the Site, Forest Supervisor Teresa Benson has closed the area to the public.

The Forest Service will be conducting additional investigations summer of 2020 to determine the full nature and extent of contamination and to better assess the degree of risk to recreational visitors, nearby residents, and to the environment.

The Site is located along the western shore of the Kern River, approximately 2 miles upstream of Isabella Lake. The mill is a former gold ore processing facility dating back to the 1860s that was associated with the nearby historic Big Blue and Sumner group of mines.

For more information regarding the area closure order, please email District Ranger Alfred Watson at

For information regarding the Forest Service's site investigation efforts, please contact Noelle Graham-Wakoski, Regional On-Scene Coordinator (858) 674-2990.