# Relationship history for MSHA mine 4405758

Current hierarchy: **Wesley D.  Burke → Plowboy 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

- **operator_operates_mine:** Southland Coal Corp → No 1 Mine; 1981-09-01 to 1983-05-15; source msha-controller-operator-history
- **controller_controls_mine:** Roberts Thomas W Et Al → No 1 Mine; 1981-09-01 to 1983-05-15; source msha-controller-operator-history
- **controller_controls_operator:** Roberts Thomas W Et Al → Southland Coal Corp; 1981-09-01 to 1983-05-15; source msha-controller-operator-history
- **operator_operates_mine:** Plowboy Coal Company Inc → No 1 Mine; 1983-05-16 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Wesley D.  Burke et al → No 1 Mine; 1983-05-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wesley D.  Burke et al → Plowboy Coal Company Inc; 1983-05-16 to current/open; source msha-controller-operator-history