# Relationship history for MSHA mine 1512144

Current hierarchy: **Garnie E  Johnson; George  Johnson → Mr Bill Coal Company Inc → No 1 Mine**

- 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:** Webb Alvin → No 1 Mine; 1978-04-01 to 1980-07-23; source msha-controller-operator-history
- **operator_operates_mine:** B & L Coal Company Inc → No 1 Mine; 1979-11-01 to 1980-07-23; source msha-controller-operator-history
- **controller_controls_operator:** Webb Alvin → B & L Coal Company Inc; 1979-11-01 to 1980-07-23; source msha-controller-operator-history
- **operator_operates_mine:** Mr Bill Coal Company Inc → No 1 Mine; 1980-07-24 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** George  Johnson et al → No 1 Mine; 1980-07-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** George  Johnson et al → Mr Bill Coal Company Inc; 1980-07-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Garnie E  Johnson et al → Mr Bill Coal Company Inc; 1980-07-24 to current/open; source msha-controller-operator-history