# Relationship history for MSHA mine 2402027

Current hierarchy: **Fergus County-Mt → Fergus County → KOLMAN SCREEN PLANT**

- 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

- **operator_operates_mine:** Fergus County → KOLMAN SCREEN PLANT; 1993-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Fergus County-Mt → KOLMAN SCREEN PLANT; 1993-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Fergus County-Mt → Fergus County; 1993-07-01 to current/open; source msha-controller-operator-history