SITE CHARACTERIZATION AND REMEDIATION PROJECT
Empire Mine State Historic Park, Nevada County
This program environmental impact report (PEIR) was prepared for the California Department of Parks and Recreation (DPR) and evaluated the potential environmental effects of a project at Empire Mine State Historic Park (park), located in Nevada County, California. The project evaluated in the PEIR consisted of characterizing, evaluating, and remediating historic mine waste and tailings at the park. In 2006, the California Department of Toxic Substances Control and the Central Valley Regional Water Quality Control Board issued a Joint Cleanup and Abatement Order, Imminent and/or Substantial Endangerment Determination, and Partial Consent Order with DPR and Newmont USA, Ltd., to oversee implementation of the project. Benchmark worked with the various stakeholders to balance differing objectives to ensure the PEIR provided a range of remediation alternatives that met regulatory requirements while ensuring DPR’s objectives of preserving the historic nature of the park were met to the extent feasible.
The draft PEIR included a tiered approach for analysis of potential environmental impacts associated with the project. We evaluated the areas identified for potential remediation efforts at a project-specific level, and we evaluated areas outside the remediation efforts at a program level. Key issues involved impacts on park users and surrounding residences as a result of noise from remediation activities, historical and archeological resources at the park, biological resources, and control and protection of surface waters associated with managing mine waste. The biggest challenge of the project was meeting strict regulatory requirements for remediating legacy mining contamination while ensuring that DPR’s objectives were met, including preserving the historic integrity of the park and ensuring that the park remained open for public use to the extent practicable. To balance the objectives of protecting historic resources with the necessity to perform remediation activities, we worked with the stakeholders to incorporate resource protection measures into the project to allow for practical implementation of the project for each remediation site at the park while preserving historic values, where possible.
Benchmark worked cooperatively with Central Valley Regional Water Control Board, Department Toxic Substances and Control, and DPR early in the drafting process to ensure all relevant stakeholders provided input. The project was required by a Joint Cleanup and Abatement Order that required remediation actions as soon as possible. Therefore, the preparation of the PEIR was expedited and the time frame from notice of preparation to final EIR certification was 15 months. The project was also completed within budget.