California’s State Mining and Geology Board had a busy 2017 with ongoing rulemakings to implement SMARA reform enacted in 2016.  The Board’s 2018 will be busy and one to closely watch too, in particular, because the Board plans to address the unintended environmental consequences created by the adoption fifteen years ago of what is known as the “Backfill Regulation.”

For those who fled California in the wake of the Backfill Regulation, here’s a quick refresher on why you packed your bags and haven’t returned.  The Backfill Regulation has two key requirements for open pit metallic mineral mines.  First, the regulation requires all open pit excavations to be backfilled to the original surface elevation.  Second, any excess material must be graded with the resulting topography not to exceed the pre-mining surface elevation by more than 25 feet.

Overall, the Backfill Regulation has been bad news for the California mining industry and the environment as explained in this February 2016 Update on the Regulatory Environment for Metallic Mines in California.  In a nutshell, the Backfill Regulation requires moving material twice (increasing GHG emissions), fails to address the proper storage and handling of waste materials (jeopardizing water quality), and can cause greater ground disturbances (impacting habitat for sensitive species).

What’s happening now?  On December 14, 2017, the Board’s Mineral Conservation and Reclamation Committee voted to begin the process to modify the Backfill Regulation to address these unintended consequences.  This first step has been taken after several years of discussions between members of the Committee and Stoel Rives, along with Golder Associates.  In particular, we have encouraged the Committee to require backfilling and ore heap reduction only when an analysis under the State’s environmental review law, the California Environmental Quality Act, indicates that those options would be the best environmental option when compared with partial backfill or no backfill alternatives.  We have also encouraged the Committee to preclude certain actions in all instances by, for example, precluding the use of tailings as pit backfill materials.  More information on these recommendations can be found in this letter and presentation.

Next steps.  The Committee now begins the process of modifying the Backfill Regulation with the State Mining and Geology Board hosting public workshops.  The workshops have not been scheduled yet, so stay tuned and watch for updates on this blog.

For more information, contact Stoel Rives’ California mining attorneys: Tom Henry (; 916-319-4667) or Michael Sherman (; 916-319-4792).