# Relationship history for MSHA mine 1516476

Current hierarchy: **Conley Meritt → Zion Mining Company → #7 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

- **controller_controls_mine:** Conley Meritt → #7 Surface; 1984-03-23 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Zion Mining Company → #7 Surface; 1988-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Conley Meritt → Zion Mining Company; 1988-09-01 to current/open; source msha-controller-operator-history