# Relationship history for MSHA mine 2302217

Current hierarchy: **Bob R  Simmons → Table Rock Asphalt Construction Company Inc → Quarry One East**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Bob R  Simmons → Quarry One East; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Table Rock Asphalt Construction Company Inc → Quarry One East; 2000-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bob R  Simmons → Table Rock Asphalt Construction Company Inc; 2000-11-01 to current/open; source msha-controller-operator-history