# Relationship history for MSHA mine 2402073

Current hierarchy: **Roy C  Volk → Volk Sand & Gravel → VOLK**

- 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:** Volk Sand & Gravel → VOLK; 1994-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Roy C  Volk → VOLK; 1994-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roy C  Volk → Volk Sand & Gravel; 1994-10-01 to current/open; source msha-controller-operator-history