# Relationship history for MSHA mine 4801169

Current hierarchy: **Campbell County-Wy → Campbell County Road & Bridge Department → Wright Pit**

- 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

- **controller_controls_mine:** Campbell County-Wy → Wright Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Hall Construction Company → Wright Pit; 1950-01-01 to 1979-08-15; source msha-controller-operator-history
- **controller_controls_mine:** Harley  Hall → Wright Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Harley  Hall → Hall Construction Company; 1950-01-01 to 1979-08-15; source msha-controller-operator-history
- **operator_operates_mine:** Campbell County Road & Bridge Department → Wright Pit; 1979-08-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Campbell County-Wy → Campbell County Road & Bridge Department; 1979-08-16 to current/open; source msha-controller-operator-history