# Relationship history for MSHA mine 1516179

Current hierarchy: **Mc Coy Gary → C G M 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:** C G M Coal Company → No 1 Surface; 1987-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mc Coy Gary → No 1 Surface; 1987-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mc Coy Gary → C G M Coal Company; 1987-09-01 to current/open; source msha-controller-operator-history