The Forest Service held workshops to 1) update the public on the status of the EIS process 2) describe the alternatives development process, and 3) solicit input on the criteria being used to evaluate alternative tailings storage facility locations.
The Forest Service is hosting workshops to solicit input on the relative importance of a variety of environmental and social criteria that they will use to evaluate alternative tailings facility locations. The Forest Service has scheduled in-person and online workshops.
The location for this alternative would enable use of cross-valley embankments/dams requiring less fill to retain tailings compared to a ring-like impoundment, simplifying construction and operations.
This alternative allows for a comparison of the impacts of slurry tailings if placed in a flatter, alluvial setting instead of an upland wash or canyon.
The only alternative proposing to use filtered tailings instead of slurry tailings. Conveyors and mobile equipment would mechanically deposit potentially acid generating tailings and non-potentially acid generating tailings in two separate, adjacent tailings storage facilities.
Shares several similarities with Alternative 2; one key difference is it proposes to reduce the amount of water retained in non-potentially acid generating (NPAG) tailings as well as reduce seepage potential through on-site thickening of NPAG tailings and ‘Thin-lift’ deposition.
A variation of the proposed action described in the May 9, 2016, version of Resolution Copper’s General Plan of Operations, this alternative would include a split-stream tailings processing method with two tailings types.
