# Relationship history for MSHA mine 2700300

Current hierarchy: **Paul  Martel; Paula  Martel → Mast Road Sand & Gravel → Mast Road Sand & 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: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Mast Road Sand & Gravel → Mast Road Sand & Gravel; 1993-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Paula  Martel et al → Mast Road Sand & Gravel; 1993-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Paula  Martel et al → Mast Road Sand & Gravel; 1993-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Paul  Martel et al → Mast Road Sand & Gravel; 1993-04-01 to current/open; source msha-controller-operator-history