# Relationship history for MSHA mine 4503443

Current hierarchy: **John  Wood → Quality Construction → COLUMBIA INDUSTRIAL PARK LLC**

- 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:** Quality Construction → COLUMBIA INDUSTRIAL PARK LLC; 2000-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John  Wood → COLUMBIA INDUSTRIAL PARK LLC; 2000-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John  Wood → Quality Construction; 2000-05-01 to current/open; source msha-controller-operator-history