# Relationship history for MSHA mine 1512169

Current hierarchy: **Hammond Chealis → River Canyon Coal Sales Inc → No 1 Tipple**

- 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:** Hopson Enterprises Inc → No 1 Tipple; 1979-11-01 to 1984-10-09; source msha-controller-operator-history
- **controller_controls_mine:** Hopson Jim → No 1 Tipple; 1979-11-01 to 1984-10-09; source msha-controller-operator-history
- **controller_controls_operator:** Hopson Jim → Hopson Enterprises Inc; 1979-11-01 to 1984-10-09; source msha-controller-operator-history
- **operator_operates_mine:** Billy'S Block & Stoker Coal → No 1 Tipple; 1984-10-10 to 1985-09-22; source msha-controller-operator-history
- **controller_controls_mine:** Billy M  Ward → No 1 Tipple; 1984-10-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Billy M  Ward → Billy'S Block & Stoker Coal; 1984-10-10 to 1985-09-22; source msha-controller-operator-history
- **operator_operates_mine:** River Canyon Coal Sales Inc → No 1 Tipple; 1985-09-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hammond Chealis → No 1 Tipple; 1985-09-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hammond Chealis → River Canyon Coal Sales Inc; 1985-09-23 to current/open; source msha-controller-operator-history