# Relationship history for MSHA mine 1506295

Current hierarchy: **Reading & Bates Corp → Black Oak Mining Company Inc → Delta Supreme Proc Plant**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Delta Supreme Coals Inc → Delta Supreme Proc Plant; 1977-01-01 to 1983-09-20; source msha-controller-operator-history
- **controller_controls_mine:** Roy R  Crawford et al → Delta Supreme Proc Plant; 1977-01-01 to 1983-09-20; source msha-controller-operator-history
- **controller_controls_operator:** Roy R  Crawford et al → Delta Supreme Coals Inc; 1977-01-01 to 1983-09-20; source msha-controller-operator-history
- **operator_operates_mine:** Black Oak Mining Company Inc → Delta Supreme Proc Plant; 1983-09-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Reading & Bates Corp → Delta Supreme Proc Plant; 1983-09-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Reading & Bates Corp → Black Oak Mining Company Inc; 1983-09-21 to current/open; source msha-controller-operator-history