Dicalite Minerals Corporation

Dicalite Minerals Corporation operates a large, open-pit diatomite mine near Burney in Shasta County, California.  Treated storm water is discharged from the facility to an intermittent tributary to Lake Britton. The RWQCB had issued orders to address elevated zinc concentrations as well as settle-able solids, suspended solids, pH, and acute toxicity detected in effluent samples above the limits set in the site-specific Waste Discharge Requirements (WDRs).  VESTRA assisted in identifying sources of elevated zinc associated with plant and quarry operations.  Because discharge and background receiving water concentrations are periodically detected above California Toxics Rule (CTR) levels, a site-specific translator was developed to set new dissolved metals criteria.  Through recent negotiations with the RWQCB, VESTRA assisted Dicalite in obtaining coverage under the General Industrial Storm Water Permit for storm water discharges and rescinding the existing WDRs, greatly reducing sampling and monitoring requirements and associated costs.

Additionally, VESTRA completed permitting of an 80-acre expansion of the Dicalite mine.  The company purchased 160 acres of adjoining land which they planned to use for overburden disposal and stockpiling in addition to mineral development.  Shasta County requested that Dicalite submit an updated Reclamation Plan, Use Permit application, and Initial Study.  The project also required preparation of a Mitigated Negative Declaration under CEQA.  VESTRA prepared the updated Reclamation Plan and Initial Study.  In addition, a Use Permit application was completed.  VESTRA biologists performed vegetation mapping and botanical reconnaissance-level surveys, as well as focused surveys for special-status species.  A Biological Characterization Report, including detailed mitigation measures to ensure sensitive species were not affected by the mine expansion activities, was submitted as part of the Initial Study.