# Relationship history for MSHA mine 0202206

Current hierarchy: **Rein-Schultz & Dahl Of Illinois Inc → Amcon Materials Company Inc → Amcon West Operation**

- 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:** Rein-Schultz & Dahl Of Illinois Inc → Amcon West Operation; 1984-04-24 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Amcon Materials Company Inc → Amcon West Operation; 1984-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rein-Schultz & Dahl Of Illinois Inc → Amcon Materials Company Inc; 1984-05-01 to current/open; source msha-controller-operator-history