# Relationship history for MSHA mine 0301783

Current hierarchy: **George A  Clark → Spa City Gravel → Spa City Gravel**

- 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:** Spa City Gravel → Spa City Gravel; 1997-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** George A  Clark → Spa City Gravel; 1997-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** George A  Clark → Spa City Gravel; 1997-03-01 to current/open; source msha-controller-operator-history