# Relationship history for MSHA mine 1002115

Current hierarchy: **MDU Resources Group Inc → Knife River → Crusher 3**

- 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:** MDU Resources Group Inc → Crusher 3; 1999-03-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Knife River → Crusher 3; 2007-06-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** MDU Resources Group Inc → Knife River; 2007-06-04 to current/open; source msha-controller-operator-history