# Relationship history for MSHA mine 1516573

Current hierarchy: **Buchanan I H Iii → Benco Mining Inc → Benco Mine No 2**

- 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

- **controller_controls_mine:** Buchanan I H Iii → Benco Mine No 2; 1987-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Benco Mining Inc → Benco Mine No 2; 1989-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Buchanan I H Iii → Benco Mining Inc; 1989-03-01 to current/open; source msha-controller-operator-history