# Relationship history for MSHA mine 1508240

Current hierarchy: **Short Bobby & Steve Hall → Redwood 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:** H & H Coal Company → No 1 Mine; 1975-05-24 to 1975-10-28; source msha-controller-operator-history
- **controller_controls_mine:** Thornsberry Gerald & J B Collins → No 1 Mine; 1975-05-24 to 1975-10-28; source msha-controller-operator-history
- **controller_controls_operator:** Thornsberry Gerald & J B Collins → H & H Coal Company; 1975-05-24 to 1975-10-28; source msha-controller-operator-history
- **operator_operates_mine:** H & H Coal Company → No 1 Mine; 1975-10-29 to 1976-09-19; source msha-controller-operator-history
- **controller_controls_mine:** Rush Bill & Lynn M Vierling → No 1 Mine; 1975-10-29 to 1976-09-19; source msha-controller-operator-history
- **controller_controls_operator:** Rush Bill & Lynn M Vierling → H & H Coal Company; 1975-10-29 to 1976-09-19; source msha-controller-operator-history
- **operator_operates_mine:** Parsons Brothers Coal Company → No 1 Mine; 1976-09-20 to 1978-04-30; source msha-controller-operator-history
- **controller_controls_mine:** Parsons Thomas J Et Al → No 1 Mine; 1976-09-20 to 1978-04-30; source msha-controller-operator-history
- **controller_controls_operator:** Parsons Thomas J Et Al → Parsons Brothers Coal Company; 1976-09-20 to 1978-04-30; source msha-controller-operator-history
- **operator_operates_mine:** Redwood Coal Company → No 1 Mine; 1978-05-01 to 1978-08-31; source msha-controller-operator-history
- **controller_controls_mine:** Banks Raymond → No 1 Mine; 1978-05-01 to 1978-08-31; source msha-controller-operator-history
- **controller_controls_operator:** Banks Raymond → Redwood Coal Company; 1978-05-01 to 1978-08-31; source msha-controller-operator-history
- **operator_operates_mine:** Redwood Coal Company → No 1 Mine; 1978-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Short Bobby & Steve Hall → No 1 Mine; 1978-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Short Bobby & Steve Hall → Redwood Coal Company; 1978-09-01 to current/open; source msha-controller-operator-history