# Relationship history for MSHA mine 4202717

Current hierarchy: **Emery County-UT → EMERY COUNTY ROAD DEPARTMENT → PORTABLE CRUSHER #2**

- 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:** Emery County-UT → PORTABLE CRUSHER #2; 1980-03-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Emery County Road Department → PORTABLE CRUSHER #2; 2020-08-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Emery County-UT → Emery County Road Department; 2020-08-03 to current/open; source msha-controller-operator-history