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Centennial Site: Understand The Issue

Rise Gold owns the toxic Centennial Site near downtown Grass Valley and is obligated to clean it up. That’s good for the community, but if the Mine is approved, they’ll use it to dump more mine waste. Even "clean" mine waste is hazardous. It presents health concerns for the community and limits what the City of Grass Valley can do with the land in the future.


A key issue is the fact that the County's Final Environmental Impact Report excludes the Centennial Site from the full analysis of the impacts of the proposed Idaho-Maryland Mine project. This prevents the County from understanding the full environmental impacts and is a clear violation of CEQA, which requires that impact assessments be based on current conditions, not a speculative future condition.

 

Included below:

  • Background

  • Final Environmental Impact Report Fails to Assess Impacts of Centennial Site

  • Next Steps on the Cleanup Plan

 

Background


Rise Gold owns two sites, the Centennial site near downtown Grass Valley off of Idaho-Maryland Road, and the larger Brunswick site at the intersection of East Bennett and Brunswick Roads.



The Centennial site is a historically toxic site that is facing EPA Superfund designation. That designation has been "conditionally deferred" for the time being because Rise Gold has agreed to clean up the site under the supervision of the CA Department of Toxic Substances Control (DTSC). The proposed Idaho-Maryland Mine project plans to use it as one of two places they’ll put their “engineered fill” using waste rock and tailings extracted from the mine.​


The goal is to restore the property to a healthy natural state, including reestablishing vegetation, reclaiming some wetlands, and letting existing seasonal creeks continue to flow. Per the zoning planned by the City of Grass Valley, open spaces would be developed as a mixed-use Business Park with some Medium Density Housing. Rise Gold is paying for the work.


The project was started in August 2019 and is completely independent of the Mine project, which is managed by the Nevada County Planning Department. For the Centennial Site cleanup, DTSC is the lead agency. It uses different inspectors. And there is no dependency on the mine being approved.


Of particular concerns is the Centennial Wetlands, which are a protected natural resource that are crucial to a functioning watershed. The currently proposed plan would destroy wetlands that shouldn't be damaged.

Barbara Rivenes from Sierra Club describes the project in this video from 2020. The dates have been extended since this video was made, but most project details remain the same.



Final Environmental Impact Report Fails to Assess Impacts of Centennial Site


The FEIR excludes the Centennial Site from the full analysis of the impacts of the mine project. This prevents the County from understanding the full environmental impacts and is a clear violation of CEQA (California Environmental Quality Act), which requires that impact assessments be based on current conditions, not a speculative future condition.


● The 56-acre Centennial site is the location of hazardous waste left over from past Idaho-Maryland Mine operations. The California Department of Toxic Substances Control (DTSC) is managing the cleanup, but their Remedial Action Plan (RAP) is only in draft form. It is unclear when the plan will be finalized or when DTSC might approve the clean up.


● Per CEQA, the EIR must provide an environmental assessment of the current conditions of a project site to establish a baseline in order to determine impacts. This was not done. The FEIR assumes the site will be cleaned up before it gets used to deposit new mine waste. The plan calls for placing 1.6 million tons of mine waste (assuming it qualifies as Group C) over the course of 5 years, covering about 44 acres to a height of up to 55 feet. And yet, the significant work needed to accomplish this clean-up is not disclosed or evaluated in the FEIR. Numerous aspects of this RAP draft have been questioned in public comments and the final project details are unknown.


Read public comments from CEA Foundation: The Centennial Clean Up Must Be Included In the EIR.


Next Steps on the Cleanup Plan

A Preliminary Endangerment Assessment (PEA) was published in 2020 that evaluated the contaminants and guided the planning for the Centennial Site. 


The first draft of a Remediation Action Plan (RAP)  was published in July 2021 and the public was invited to comment. Under CEQA, this is a "Mitigated Negative Declaration", which examines the impacts and proposed mitigations (such as how to mitigate the damage to wetlands that will get dug up during the cleanup.) DTSC has not published a schedule for the second draft yet.


Learn more about comments on the Centennial Site provided by CEA Foundation and coalition partners.  



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