# Relationship history for MSHA mine 3901467

Current hierarchy: **Brule County Highway Department → Brule County Hwy Dept. → Brule Screener #1**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Brule County Highway Department → Brule Screener #1; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Brule County Hwy Dept. → Brule Screener #1; 2001-12-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Brule County Highway Department → Brule County Hwy Dept.; 2001-12-04 to current/open; source msha-controller-operator-history