# Relationship history for MSHA mine 2501302

Current hierarchy: **Kreg W  Mitteis → Willow Creek Sand and Gravel → Knox County Nickels Pit**

- 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:** Kreg W  Mitteis → Knox County Nickels Pit; 2009-12-08 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Willow Creek Sand and Gravel → Knox County Nickels Pit; 2017-08-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kreg W  Mitteis → Willow Creek Sand and Gravel; 2017-08-17 to current/open; source msha-controller-operator-history