# Relationship history for MSHA mine 5001799

Current hierarchy: **Don E Conrad → Conrad Contracting → Portage 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:** Conrad Contracting → Portage Gravel; 2004-05-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Don E Conrad → Portage Gravel; 2004-05-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Don E Conrad → Conrad Contracting; 2004-05-26 to current/open; source msha-controller-operator-history