# Relationship history for MSHA mine 4201429

Current hierarchy: **Energy Fuels Inc → EFR White Mesa LLC → White Mesa Mill**

- 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:** Energy Fuels Nuclear Inc → White Mesa Mill; 1950-01-01 to 1984-01-08; source msha-controller-operator-history
- **controller_controls_mine:** Harold  Roberts → White Mesa Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Harold  Roberts → Energy Fuels Nuclear Inc; 1950-01-01 to 1984-01-08; source msha-controller-operator-history
- **operator_operates_mine:** Umetco Minerals Corp → White Mesa Mill; 1984-01-09 to 1994-05-25; source msha-controller-operator-history
- **controller_controls_mine:** Umetco Minerals Corp et al → White Mesa Mill; 1984-01-09 to 1994-05-25; source msha-controller-operator-history
- **controller_controls_operator:** Umetco Minerals Corp et al → Umetco Minerals Corp; 1984-01-09 to 1994-05-25; source msha-controller-operator-history
- **operator_operates_mine:** Energy Fuels Nuclear Inc → White Mesa Mill; 1994-05-26 to 1997-05-09; source msha-controller-operator-history
- **controller_controls_operator:** Harold  Roberts → Energy Fuels Nuclear Inc; 1994-05-26 to 1997-05-09; source msha-controller-operator-history
- **operator_operates_mine:** Energy Fuels Resources (USA) Inc. → White Mesa Mill; 1997-05-10 to 2025-02-09; source msha-controller-operator-history
- **controller_controls_mine:** International Uranium Corp → White Mesa Mill; 1997-05-10 to 2023-02-12; source msha-controller-operator-history
- **controller_controls_operator:** International Uranium Corp → Energy Fuels Resources (USA) Inc.; 1997-05-10 to 2023-02-12; source msha-controller-operator-history
- **controller_controls_mine:** Energy Fuels Inc → White Mesa Mill; 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 White Mesa LLC → White Mesa Mill; 2025-02-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Energy Fuels Inc → White Mesa Mill; 2025-02-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Energy Fuels Inc → EFR White Mesa LLC; 2025-02-10 to current/open; source msha-controller-operator-history