# Relationship history for MSHA mine 4400083

Current hierarchy: **John W  Barnette Jr → Rim Rock Quarries Inc → Natural Tunnell Plant**

- 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:** Natural Tunnel Stone Company Inc → Natural Tunnell Plant; 1950-01-01 to 1985-07-18; source msha-controller-operator-history
- **controller_controls_mine:** William C Hunter et al → Natural Tunnell Plant; 1950-01-01 to 1985-07-18; source msha-controller-operator-history
- **controller_controls_operator:** William C Hunter et al → Natural Tunnel Stone Company Inc; 1950-01-01 to 1985-07-18; source msha-controller-operator-history
- **controller_controls_mine:** John W  Barnette Jr → Natural Tunnell Plant; 1979-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Rim Rock Quarries Inc → Natural Tunnell Plant; 1985-07-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John W  Barnette Jr → Rim Rock Quarries Inc; 1985-07-19 to current/open; source msha-controller-operator-history