# Relationship history for MSHA mine 1002052

Current hierarchy: **Kirk  Burns → Burns Concrete Inc → Portable Plant**

- 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

- **controller_controls_mine:** Kirk  Burns → Portable Plant; 1993-10-14 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Burns Concrete Inc → Portable Plant; 2004-04-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kirk  Burns → Burns Concrete Inc; 2004-04-07 to current/open; source msha-controller-operator-history