# Relationship history for MSHA mine 2501089

Current hierarchy: **Kearney County-NE → Kearney County Road Department → Kearney County Gravel Operation**

- 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:** Kearney County Road Department → Kearney County Gravel Operation; 1987-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Kearney County-NE → Kearney County Gravel Operation; 1987-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kearney County-NE → Kearney County Road Department; 1987-06-01 to current/open; source msha-controller-operator-history