# Relationship history for MSHA mine 1509457

Current hierarchy: **Walsh Eugene & William J Morse → Ohio River Coal Company → J & B 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:** Ohio River Coal Company → J & B Mine; 1975-12-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Walsh Eugene & William J Morse → J & B Mine; 1975-12-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Walsh Eugene & William J Morse → Ohio River Coal Company; 1975-12-20 to current/open; source msha-controller-operator-history