# Relationship history for MSHA mine 4200769

Current hierarchy: **Energy Fuels Inc → EFR Colorado Plateau LLC → La Sal Complex**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Umetco Minerals Corp → La Sal Complex; 1950-01-01 to 2010-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Union Carbide Corp → La Sal Complex; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Union Carbide Corp → Umetco Minerals Corp; 1950-01-01 to 2010-12-31; source msha-controller-operator-history
- **controller_controls_mine:** International Uranium Corp → La Sal Complex; 1997-05-10 to 2023-02-12; source msha-controller-operator-history
- **operator_operates_mine:** Energy Fuels Resources (USA) Inc. → La Sal Complex; 2011-01-01 to 2025-02-09; source msha-controller-operator-history
- **controller_controls_operator:** International Uranium Corp → Energy Fuels Resources (USA) Inc.; 2011-01-01 to 2023-02-12; source msha-controller-operator-history
- **controller_controls_mine:** Energy Fuels Inc → La Sal Complex; 2023-02-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Energy Fuels Inc → Energy Fuels Resources (USA) Inc.; 2023-02-13 to 2025-02-09; source msha-controller-operator-history
- **operator_operates_mine:** EFR Colorado Plateau LLC → La Sal Complex; 2025-02-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Energy Fuels Inc → La Sal Complex; 2025-02-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Energy Fuels Inc → EFR Colorado Plateau LLC; 2025-02-10 to current/open; source msha-controller-operator-history