Long-range mine planning indicated that approximately 160 million tons of rockfill would be produced during mining between 2022 and 2031 following construction of the 6,450-foot embankment lift. As part of a risk assessment of the YDTI conducted in 2018, the selective and strategic use of excess rockfill generated during mining of the Continental Pit was identified as an opportunity to enhance embankment stability. The Horseshoe Bend (HsB) area was selected as a priority rock disposal site (RDS) location, as it would result in substantial benefit to the tailings facility by enhancing embankment stability and improving reclamation opportunities.
Amendment 11 was reviewed by the IRP who issued a Memorandum, supporting placement of additional rockfill in the HsB area, with final permit approval being issued by DEQ.
Design Documents
- Horseshoe Bend Application for Permit Modification (PDF, 2 MB)
- Horseshoe Bend Permit Modification Figures 1-6 (PDF, 7 MB)
- Horseshoe Bend Permit Modification Attachments 1-5 (PDF, 23 MB)
Independent Review Panel
- IRP Memorandum (PDF, 109 KB)
Environmental Assessment
- Final Environmental Assessment – Amendment 11 (PDF, 8 MB)
Decision Notice
- DEQ Approval to Amend Permit No. 00030 – Amendment 11 (PDF, 213 KB)