# Relationship history for MSHA mine 4503728

Current hierarchy: **United States Government → East Columbia Basin Irrigation District → Campbell 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** East Columbia Basin Irrigation District → Campbell Pit; 2014-06-11 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** United States Government → Campbell Pit; 2014-06-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** United States Government → East Columbia Basin Irrigation District; 2014-06-11 to current/open; source msha-controller-operator-history