# Relationship history for MSHA mine 3002067

Current hierarchy: **Hubert  Wightman → Sand Hill Gravel → SAND HILL 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:** Allegany County Department Of Highways → SAND HILL GRAVEL; 1950-01-01 to 1999-02-21; source msha-controller-operator-history
- **controller_controls_mine:** Allegany County-Ny → SAND HILL GRAVEL; 1950-01-01 to 1999-02-21; source msha-controller-operator-history
- **controller_controls_operator:** Allegany County-Ny → Allegany County Department Of Highways; 1950-01-01 to 1999-02-21; source msha-controller-operator-history
- **operator_operates_mine:** Sand Hill Gravel → SAND HILL GRAVEL; 1999-02-22 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hubert  Wightman → SAND HILL GRAVEL; 1999-02-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hubert  Wightman → Sand Hill Gravel; 1999-02-22 to current/open; source msha-controller-operator-history