# Relationship history for MSHA mine 0301610

Current hierarchy: **Brad  De Vazier → Crowley'S Ridge Sand & Gravel Company Inc → CROWLEYS RIDGE SAND AND GRAVEL P**

- 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:** Crowleys Ridge Sand & Gravel Inc → CROWLEYS RIDGE SAND AND GRAVEL P; 1986-06-01 to 1992-04-09; source msha-controller-operator-history
- **controller_controls_mine:** Laws W L → CROWLEYS RIDGE SAND AND GRAVEL P; 1986-06-01 to 1992-04-09; source msha-controller-operator-history
- **controller_controls_operator:** Laws W L → Crowleys Ridge Sand & Gravel Inc; 1986-06-01 to 1992-04-09; source msha-controller-operator-history
- **operator_operates_mine:** Crowley'S Ridge Sand & Gravel Company Inc → CROWLEYS RIDGE SAND AND GRAVEL P; 1992-04-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Brad  De Vazier → CROWLEYS RIDGE SAND AND GRAVEL P; 1992-04-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Brad  De Vazier → Crowley'S Ridge Sand & Gravel Company Inc; 1992-04-10 to current/open; source msha-controller-operator-history