# Relationship history for MSHA mine 1510600

Current hierarchy: **Cantrell Burl Jr → Walnut Bend Coal Company → No 1 Surface**

- 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:** Walnut Bend Coal Company → No 1 Surface; 1977-07-01 to 1978-07-24; source msha-controller-operator-history
- **controller_controls_mine:** Downend Arthur A → No 1 Surface; 1977-07-01 to 1978-07-24; source msha-controller-operator-history
- **controller_controls_operator:** Downend Arthur A → Walnut Bend Coal Company; 1977-07-01 to 1978-07-24; source msha-controller-operator-history
- **operator_operates_mine:** Walnut Bend Coal Company → No 1 Surface; 1978-07-25 to 1980-04-09; source msha-controller-operator-history
- **controller_controls_mine:** Finn Earl W → No 1 Surface; 1978-07-25 to 1980-04-09; source msha-controller-operator-history
- **controller_controls_operator:** Finn Earl W → Walnut Bend Coal Company; 1978-07-25 to 1980-04-09; source msha-controller-operator-history
- **operator_operates_mine:** Walnut Bend Coal Company → No 1 Surface; 1980-04-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cantrell Burl Jr → No 1 Surface; 1980-04-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cantrell Burl Jr → Walnut Bend Coal Company; 1980-04-10 to current/open; source msha-controller-operator-history