Mining Program - Sulphur Creek (Colusa County) Mining District Remediation

Sulphur Creek (Colusa County) Mining District Remediation

Questions and Comments

This webpage contains documents related to the mining district and cleanup process in the Sulphur Creek watershed in Colusa County. Questions and comments may be directed to Jeff Huggins at (916) 464-4639 or by email at

  • Cache Creek Watershed Mercury Basin Plan Amendment (Resolution R5-2005-0146)
    In October 2005, the Central Valley Water Board adopted an implementation plan for controlling mercury in the Cache Creek watershed. This plan contains requirements for controlling the discharge of mercury from inactive mines in the Sulphur Creek watershed.
  • Sulphur Creek Water Quality Objectives (Resolution R5-2007-0021)
    In March 2007, the Central Valley Water Board adopted water quality objectives specific to Sulphur Creek that are based on naturally occurring levels of mercury and determined that Sulphur Creek should not be designated as a source of drinking water.
  • Sulphur Creek TMDL Report
    The Sulphur Creek Mercury TMDL Report is a technical document that contains data for mercury in sediment and water and staff's estimates of mercury loads.
  • Calfed Mercury Program
    In 2000-2002, the California Bay-Delta Program funded studies of mercury in the Cache Creek watershed and the Sacramento-San Joaquin River Delta. You may follow the links below to the Calfed Mercury Program reports that provide data and results for mine sites and natural geologic features in the Sulphur Creek watershed. The Central Valley Water Board is providing links to these reports for informational purposes. Responsible parties may propose cleanup actions that are different than those in the Tetra Tech report.
    • "Assessment of the Feasibility of Remediation of Mercury Mine Sources in the Cache Creek Watershed" (California Department of Conservation), provides concentrations of mercury in soil samples and estimated rates of erosion from mine site features and nonmined slopes.
    • "Final Engineering Evaluation and Cost Analysis for the Sulphur Creek Mining District" (Tetra Tech EM, Inc.), provides alternatives for cleanup strategies, evaluates them by effectiveness of reducing mercury discharges, and estimates costs.