# Relationship history for MSHA mine 4604689

Current hierarchy: **Jackson Vicki → Big Ben Coal Company → 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:** A & W Mining Company → No 1 Mine; 1975-06-27 to 1976-05-12; source msha-controller-operator-history
- **controller_controls_mine:** Burks William & Auldy → No 1 Mine; 1975-06-27 to 1976-05-12; source msha-controller-operator-history
- **controller_controls_operator:** Burks William & Auldy → A & W Mining Company; 1975-06-27 to 1976-05-12; source msha-controller-operator-history
- **operator_operates_mine:** Big Ben Coal Company → No 1 Mine; 1976-05-13 to 1976-11-27; source msha-controller-operator-history
- **controller_controls_mine:** Hurley Sonja → No 1 Mine; 1976-05-13 to 1976-11-27; source msha-controller-operator-history
- **controller_controls_operator:** Hurley Sonja → Big Ben Coal Company; 1976-05-13 to 1976-11-27; source msha-controller-operator-history
- **operator_operates_mine:** Big Ben Coal Company → No 1 Mine; 1976-11-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Jackson Vicki → No 1 Mine; 1976-11-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jackson Vicki → Big Ben Coal Company; 1976-11-28 to current/open; source msha-controller-operator-history