# Relationship history for MSHA mine 2901726

Current hierarchy: **Unc Resources Inc → Unc Mining & Milling → Old Churchrock Mine**

- 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:** Unc Resources Inc → Old Churchrock Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Unc Mining & Milling → Old Churchrock Mine; 1978-03-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Unc Resources Inc → Unc Mining & Milling; 1978-03-09 to current/open; source msha-controller-operator-history