# Relationship history for MSHA mine 4608793

Current hierarchy: **Progress Energy Inc → Black Hawk Synfuel LLC → Black Hawk Synfuel**

- 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:** Black Hawk Synfuel LLC → Black Hawk Synfuel; 1999-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Florida Progress Corporation → Black Hawk Synfuel; 1999-09-01 to 2003-06-15; source msha-controller-operator-history
- **controller_controls_operator:** Florida Progress Corporation → Black Hawk Synfuel LLC; 1999-09-01 to 2003-06-15; source msha-controller-operator-history
- **controller_controls_mine:** Progress Energy Inc → Black Hawk Synfuel; 2003-06-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Progress Energy Inc → Black Hawk Synfuel LLC; 2003-06-16 to current/open; source msha-controller-operator-history